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Bievel-Radulescu R, Ferrari S, Piaia M, Mandatori D, Pandolfi A, Nubile M, Mastropasqua L, Stanca HT, Ponzin D. Banking of post-SMILE stromal lenticules for additive keratoplasty: A new challenge for eye banks? Int Ophthalmol 2024; 44:355. [PMID: 39182212 PMCID: PMC11345333 DOI: 10.1007/s10792-024-03283-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2024] [Accepted: 08/17/2024] [Indexed: 08/27/2024]
Abstract
PURPOSE ReLEx (Refractive Lenticule Extraction) Small Incision Lenticule Extraction (SMILE), the second generation of ReLEx Femtosecond Lenticule Extraction (FLEx), is a minimally invasive, flapless procedure designed to treat refractive errors such as myopia, hyperopia, presbyopia, and astigmatism. This review aims to provide a comprehensive overview of the methods for preserving SMILE-derived lenticules and discusses their potential future applications. METHODS A narrative literature review was conducted using PubMed, Scopus, and Web of Science databases, focusing on articles published up to January 2024 and available in English. The authors also evaluated the reference lists of the collected papers to identify any additional relevant research. RESULTS No standardized protocols currently exist for the storage or clinical application of SMILE-derived lenticules. However, these lenticules present a promising resource for therapeutic uses, particularly in addressing the shortage of donor corneal tissues. Their potential applications include inlay and overlay additive keratoplasty, as well as other ocular surface applications. Further research is needed to establish reliable protocols for their preservation and clinical use. CONCLUSION SMILE-derived lenticules offer significant potential as an alternative to donor corneal tissues. Standardizing their storage and application methods could enhance their use in clinical settings.
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Affiliation(s)
- Raluca Bievel-Radulescu
- Fondazione Banca Degli Occhi del Veneto, Via Paccagnella, 11, 30174, Venice, Italy.
- Department of Ophthalmology, "Carol Davila" University of Medicine and Pharmacy, 030167, Bucharest, Romania.
| | - Stefano Ferrari
- Fondazione Banca Degli Occhi del Veneto, Via Paccagnella, 11, 30174, Venice, Italy
| | - Moreno Piaia
- Fondazione Banca Degli Occhi del Veneto, Via Paccagnella, 11, 30174, Venice, Italy
| | - Domitilla Mandatori
- Department of Medicine and Aging Science, Ophthalmology Clinic, University G. D'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| | - Assunta Pandolfi
- Department of Medicine and Aging Science, Ophthalmology Clinic, University G. D'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| | - Mario Nubile
- StemTeCh Group, Department of Medical, Oral and Biotechnological Sciences, Center for Advanced Studies and Technology-CAST, University G. D'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| | - Leonardo Mastropasqua
- StemTeCh Group, Department of Medical, Oral and Biotechnological Sciences, Center for Advanced Studies and Technology-CAST, University G. D'Annunzio of Chieti-Pescara, 66100, Chieti, Italy
| | - Horia Tudor Stanca
- Department of Ophthalmology, "Carol Davila" University of Medicine and Pharmacy, 030167, Bucharest, Romania
| | - Diego Ponzin
- Fondazione Banca Degli Occhi del Veneto, Via Paccagnella, 11, 30174, Venice, Italy
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Castillejo Becerra CM, Maguire LJ, Salomao DR, Patel SV. Outcomes of Flap Amputation After Laser In Situ Keratomileusis. Cornea 2024; 43:961-965. [PMID: 38015972 DOI: 10.1097/ico.0000000000003440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 10/30/2023] [Indexed: 11/30/2023]
Abstract
PURPOSE The aim of this study was to describe the indications and outcomes of flap amputation after laser in situ keratomileusis (LASIK) at a referral-based institution. METHODS In this retrospective consecutive case series, medical records of patients who underwent LASIK flap amputation at Mayo Clinic, Rochester, MN, between January 1, 1998, and January 31, 2023, were reviewed. RESULTS Fifteen eyes (15 patients) underwent flap amputation during the study period. The median age was 45 years (range, 25-71 years), and 8 patients (53%) were men. The median uncorrected visual acuity before flap amputation was 20/200 (range 20/40-hand motions). Indications for flap amputation included epithelial ingrowth (n = 6, 40%), infectious keratitis (n = 6, 40%), diffuse lamellar keratitis (n = 1, 7%), vegetative foreign body (n = 1, 7%), and astigmatism from fixed flap striae (n = 1, 7%). The median duration of follow-up was 8 months (range 1-234 months). Subsequent corneal interventions included chelation of calcific band keratopathy (n = 1, 7%), lamellar keratoplasty (n = 1, 7%), penetrating keratoplasty (n = 2, 18%), keratoprosthesis (n = 1, 7%), and rigid contact lens wear (n = 4, 27%). The final median best visual acuity was 20/25 (range 20/20-20/200). Compared with noninfectious indications for flap amputation, eyes with infectious indications had worse baseline median uncorrected visual acuity (hand motions vs. 20/63, P < 0.001), were more likely to undergo major corneal surgical intervention (50% vs. 11%), and had worse final median best visual acuity (20/50 vs. 20/20, P = 0.018). CONCLUSIONS LASIK flap amputation is sometimes necessary to control threatening corneal diseases. Excellent visual outcomes were achieved in most cases, albeit with additional intervention or rigid contact lens wear.
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Affiliation(s)
| | - Leo J Maguire
- Department of Ophthalmology, Mayo Clinic, Rochester, MN; and
| | - Diva R Salomao
- Department of Ophthalmology, Mayo Clinic, Rochester, MN; and
- Department of Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN
| | - Sanjay V Patel
- Department of Ophthalmology, Mayo Clinic, Rochester, MN; and
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Li L, Xiong L, Wang Z. Comparison of clinical outcomes of a corneal wavefront- and topography-guided platforms for laser in situ keratomileusis on virgin eyes: an expanded cohort study. Int Ophthalmol 2024; 44:331. [PMID: 39037500 PMCID: PMC11263421 DOI: 10.1007/s10792-024-03235-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Accepted: 06/22/2024] [Indexed: 07/23/2024]
Abstract
PURPOSE To compare the clinical outcomes of myopiacorrected with corneal-wavefront-guided (CWG) laser in situ keratomileusis (LASIK) with AMARIS 1050S (SCHWIND eye-tech-solutions GmbH & Co. KG) and corneal-topography-guided (CTG) LASIK with WaveLight EX500 (Alcon Laboratories, Fort Worth, TX). METHODS In this prospective, pseudo-randomized expanded cohort study, a total of 266 patients were subjected to binocular LASIK surgery, either with WaveLight EX500 (WaveLight group) or Amaris 1050S (AMARIS group) platforms. Data related to right eyes were selected for analysis. Corneal higher-order aberration (HOA) was selected as the primary endpoint; while visual acuity and refraction were the secondary endpoints. All the endpoints were assessed at 3 months postoperatively. RESULTS There were 134 eyes in the AMARIS group and 132 eyes in the WaveLight group. After 3 months of postoperative follow-up, spherical and coma aberrations were significantly lower (P < 0.05) in the WaveLight group (spherical aberration: - 0.104 ± 0.199 µm; coma aberration: - 0.117 ± 0.202 µm) in comparison with the AMARIS group (spherical aberrations: 0.254 ± 0.146 µm; coma aberrations: 0.316 ± 0.297 µm). In the AMARIS group, 96.3% of the eyes achieved an uncorrected distance visual acuity (UDVA) of 20/20 while in the WaveLight group, 96.2% of the eyes achieved an UDVA of 20/20. Furthermore, the mean postoperative manifest refraction spherical equivalent (MRSE) was - 0.02 ± 0.28 in the AMARIS group and - 0.05 ± 0.21 in the WaveLight group (P = 0.34). CONCLUSIONS Both WaveLight EX500 and Amaris 1050S LASIK showed excellent refractive and visual outcomes. In addition, the WaveLight group showed minimal spherical and coma aberrations when compared to the AMARIS group.
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Affiliation(s)
- Li Li
- Chongqing Eye and Vision Care Hospital, Chongqing, China
| | - Lu Xiong
- Department of Refractive Surgery, Guangzhou Aier Eye Hospital, Guangzhou, China
- Aier Institute of Refractive Surgery, Aier Eye Hospital Group, Changsha, China
| | - Zheng Wang
- Aier School of Ophthalmology, Central South University, Fourth Floor, New Century Mansion, 198 Middle Furong Road, Changsha, 410015, China.
- Department of Refractive Surgery, Guangzhou Aier Eye Hospital, Guangzhou, China.
- Aier Institute of Refractive Surgery, Aier Eye Hospital Group, Changsha, China.
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Wijesinghe RE, Kahatapitiya NS, Lee C, Han S, Kim S, Saleah SA, Seong D, Silva BN, Wijenayake U, Ravichandran NK, Jeon M, Kim J. Growing Trend to Adopt Speckle Variance Optical Coherence Tomography for Biological Tissue Assessments in Pre-Clinical Applications. MICROMACHINES 2024; 15:564. [PMID: 38793137 PMCID: PMC11122893 DOI: 10.3390/mi15050564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2024] [Revised: 04/19/2024] [Accepted: 04/22/2024] [Indexed: 05/26/2024]
Abstract
Speckle patterns are a generic feature in coherent imaging techniques like optical coherence tomography (OCT). Although speckles are granular like noise texture, which degrades the image, they carry information that can be benefited by processing and thereby furnishing crucial information of sample structures, which can serve to provide significant important structural details of samples in in vivo longitudinal pre-clinical monitoring and assessments. Since the motions of tissue molecules are indicated through speckle patterns, speckle variance OCT (SV-OCT) can be well-utilized for quantitative assessments of speckle variance (SV) in biological tissues. SV-OCT has been acknowledged as a promising method for mapping microvasculature in transverse-directional blood vessels with high resolution in micrometers in both the transverse and depth directions. The fundamental scope of this article reviews the state-of-the-art and clinical benefits of SV-OCT to assess biological tissues for pre-clinical applications. In particular, focus on precise quantifications of in vivo vascular response, therapy assessments, and real-time temporal vascular effects of SV-OCT are primarily emphasized. Finally, SV-OCT-incorporating pre-clinical techniques with high potential are presented for future biomedical applications.
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Affiliation(s)
- Ruchire Eranga Wijesinghe
- Department of Electrical and Electronic Engineering, Faculty of Engineering, Sri Lanka Institute of Information Technology, Malabe 10115, Sri Lanka;
- Center for Excellence in Intelligent Informatics, Electronics & Transmission (CIET), Sri Lanka Institute of Information Technology, Malabe 10115, Sri Lanka
| | - Nipun Shantha Kahatapitiya
- Department of Computer Engineering, Faculty of Engineering, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka; (N.S.K.); (U.W.)
| | - Changho Lee
- Department of Artificial Intelligence Convergence, Chonnam National University, Gwangju 61186, Republic of Korea
- Department of Nuclear Medicine, Chonnam National University Medical School & Hwasun Hospital, 264, Seoyang-ro, Hwasun 58128, Republic of Korea
| | - Sangyeob Han
- ICT Convergence Research Center, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Shinheon Kim
- ICT Convergence Research Center, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Sm Abu Saleah
- ICT Convergence Research Center, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Daewoon Seong
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Bhagya Nathali Silva
- Center for Excellence in Intelligent Informatics, Electronics & Transmission (CIET), Sri Lanka Institute of Information Technology, Malabe 10115, Sri Lanka
- Faculty of Computing, Sri Lanka Institute of Information Technology, Malabe 10115, Sri Lanka
| | - Udaya Wijenayake
- Department of Computer Engineering, Faculty of Engineering, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka; (N.S.K.); (U.W.)
| | - Naresh Kumar Ravichandran
- Center for Scientific Instrumentation, Korea Basic Science Institute, 169-148, Gwahak-ro, Yuseong-gu, Daejeon 34133, Republic of Korea
| | - Mansik Jeon
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
| | - Jeehyun Kim
- School of Electronic and Electrical Engineering, College of IT Engineering, Kyungpook National University, 80, Daehak-ro, Buk-gu, Daegu 41566, Republic of Korea
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Miyagawa R, Ohgai T, Yoshikawa S, Lim HH, Rezvani S, Taira T, Eryu O. Effects of laser pulse duration on the formation dynamics of laser-induced periodic nanostructures. OPTICS EXPRESS 2024; 32:11863-11872. [PMID: 38571024 DOI: 10.1364/oe.520565] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 03/07/2024] [Indexed: 04/05/2024]
Abstract
Formation dynamics of laser-induced periodic surface structures (LIPSSs) on the SiC substrates were described with varying pulse numbers and pulse duration. As the number of laser pulses increases, two significant transformations become evident in the progression of structural formations. First from surface roughening with nanoparticles to LIPSS with the period that is slightly shorter than the laser wavelength. Second it turns to LIPSS with a period less than half the laser wavelength. It is found that maintaining the crystallinity is the key to changing the structures. In the cases of longer pulse width than sub-nanoseconds, no LIPSS formations are observed or LSFL does not change to HSFL because the irradiated area is poly-crystallized.
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Hu CW, Lu CY, Wen YC, Chen HW. An economical single-shot pulse picker without nonlinear effect and dispersion. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2024; 95:013003. [PMID: 38214591 DOI: 10.1063/5.0185458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Accepted: 12/23/2023] [Indexed: 01/13/2024]
Abstract
An economical and stable single-shot pulse picker design without dispersion, nonlinear effect, and limitation on wavelength is proposed. This design is composed of a periodic pulse blocker (PPB), a control unit, and a mechanical shutter. It has successfully been applied to the commercial high-fluence femtosecond laser with 11-mm beam diameter, 2-mJ pulse energy, and 1-kHz repetition rate. Significantly, by incorporating commercial optical choppers equipped with custom-designed chopper blades in the PPB, this design can accommodate lasers with fluences reaching 610 mJ/cm2 and the standard 1 kHz repetition rate typical of high-fluence lasers. Furthermore, the proposed design provides a cost-effective substitute compared to using electro-optic modulators or acousto-optic modulators.
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Affiliation(s)
- Chen-Wei Hu
- International Intercollegiate Ph.D. Program, National Tsing Hua University, 30013 Hsinchu, Taiwan
| | - Chia-Yen Lu
- Institute and Undergraduate Program of Electro-Optical Engineering, National Taiwan Normal University, Taipei 11677, Taiwan
| | - Yu-Chieh Wen
- Institute of Physics, Academia Sinica, 115201 Taipei City, Taiwan
| | - Hung-Wen Chen
- International Intercollegiate Ph.D. Program, National Tsing Hua University, 30013 Hsinchu, Taiwan
- Institute of Photonics Technologies, National Tsing Hua University, 30013 Hsinchu, Taiwan
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Yang S, Wang H, Chen Z, Li Y, Chen Y, Long Q. Possible risk factors of opaque bubble layer and its effect on high-order aberrations after small incision Lenticule extraction. Front Med (Lausanne) 2023; 10:1156677. [PMID: 38179268 PMCID: PMC10765512 DOI: 10.3389/fmed.2023.1156677] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Accepted: 11/30/2023] [Indexed: 01/06/2024] Open
Abstract
Purpose To evaluate the possible risk factors of opaque bubble layer (OBL) formation in small incision lenticule extraction (SMILE) surgery and its effects on visual quality. Methods Fifty-six eyes from 28 patients were included in this study. The preoperative parameters and intraoperative designs were recorded. Corneal high-order aberrations (HOAs), point spread function (PSF), and modulation transfer function (MTF) were measured using iTrace at pre-operation, 1 week, 1 month, and 3 months after SMILE. Generalized Estimating Equation and Linear Mixed Effects Model were employed for statistical analysis. Results The mean OBL area in SMILE surgery was 2.75% ± 1.25%. The patients were divided into groups based on whether the OBL was greater than the mean group or less than the mean group. Compared to the group with a smaller OBL area, the group with the larger OBL area had steeper corneal curvature and thinner cap thickness, the OBL area was positively correlated with the preoperative keratometry (r = 0.21, p = 0.04) and preoperative spherical value (r = 0.47, p = 0.01). The group with the larger OBL area induced more corneal SA and trefoil at 1 week postoperatively, but the difference was not significant at 1 month and 3 months postoperatively. Conclusion A steep corneal curvature, thin cap thickness, and high preoperative spherical value are possible risk factors for OBL formation in SMILE surgery. The OBL increased the ocular and corneal HOAs postoperatively for a short period (1 week), while it did not affect the long-term outcomes.
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Affiliation(s)
| | | | | | | | - Youxin Chen
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
| | - Qin Long
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China
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Ladi JS, Gaikwad A, Shah NA. Comparative study of small incision refractive lenticule extraction with 5 mm versus 6.5 mm optic zone for myopia. Indian J Ophthalmol 2023; 71:2717-2721. [PMID: 37417110 PMCID: PMC10491035 DOI: 10.4103/ijo.ijo_2559_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2022] [Revised: 03/31/2023] [Accepted: 04/05/2023] [Indexed: 07/08/2023] Open
Abstract
Purpose To compare residual stromal thickness (RST) in eyes undergoing small incision refractive lenticule extraction (SMILE) using a lenticular diameter of 6.5 mm versus those with a diameter of 5 mm. Methods: In this retrospective comparative case series. , consecutive patients who underwent SMILE between 2016 and 2021 with at least 6 months of follow-up were included. Preoperative best-corrected distance visual acuity (BCDVA), refractive error, contrast sensitivity, central corneal thickness, keratometry, higher order aberrations, and scotopic pupil size were recorded using a Placido disk topography with Sheimpflug tomography-based system. Patients underwent SMILE with a lenticular diameter of 6.5 mm until 2018 (n = 372 eyes). Thereafter, the lenticular diameter was reduced to 5 mm (n = 318). The RST, postoperative refraction, aberrations, subjective glare, and halos were compared across groups at 1 and 6 months. Results The mean age of participants was 26.8 ± 5.8 years with a mean preoperative spherical equivalent of -4.48 D ± 2.16 D (range: -0.75 to -12.25 D) and mean scotopic pupil of 3.7 ± 0.75 mm. Eyes in the 5 mm group had 30.6 m (95% confidence interval [CI] = 28 to 33 m, P < 0.001) greater RST compared to the 6.5 mm group after adjusting for spherical equivalent and preoperative pachymetry. There were no differences in vision, contrast sensitivity, aberrations (wavefront error of 0.19 ± 0.2 vs. 0.25 ± 0.2, P = 0.19) or glare between the two groups. Conclusion SMILE performed with a lenticular diameter of 5 mm leads to greater RST across the myopic range, but without inducing significant higher-order aberrations.
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Affiliation(s)
- Jeevan S Ladi
- Department of Ophthalmology, Dada Laser Eye Institute, Pune, Maharashtra, India
| | - Anita Gaikwad
- Department of Ophthalmology, Dada Laser Eye Institute, Pune, Maharashtra, India
| | - Nitant A Shah
- Department of Ophthalmology, Dada Laser Eye Institute, Pune, Maharashtra, India
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Yusef YN, Ermakova SV, Sheludchenko VM, Alkharki L. [Complications of femto-LASIK and features of cavitation injuries]. Vestn Oftalmol 2023; 139:119-125. [PMID: 37379118 DOI: 10.17116/oftalma2023139031119] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/30/2023]
Abstract
Modern approach to refractive laser surgery features three main types of lamellar surgery. Two of them are types of open laser keratomileusis (LASIK and femtosecond laser-assisted LASIK), and the third - closed (SMILE). All of these techniques allow achieving good clinical outcomes but differ in possible complications. This article reviews the complications of femto-LASIK and specifically the post-operative cavitation injuries, describes the mechanism of their occurrence, variants of their course, and presents the prevention measures.
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Affiliation(s)
- Yu N Yusef
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University (Sechenov University), Moscow, Russia
| | - S V Ermakova
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
| | | | - L Alkharki
- Krasnov Research Institute of Eye Diseases, Moscow, Russia
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VisuMax Flap 2.0: a flap plus technique to reduce incidence of an opaque bubble layer in femtosecond laser–assisted LASIK. Graefes Arch Clin Exp Ophthalmol 2022; 261:1187-1194. [PMID: 36374312 PMCID: PMC10049947 DOI: 10.1007/s00417-022-05894-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2022] [Revised: 10/18/2022] [Accepted: 11/03/2022] [Indexed: 11/16/2022] Open
Abstract
Abstract
Purpose
To evaluate the incidence of an opaque bubble layer (OBL) in femtosecond laser–assisted in situ keratomileusis (FS-LASIK) flaps created with VisuMax Flap 2.0 as a result of a modification in the parameters of the flap programming.
Methods
This retrospective study was comprised of 1400 eyes of 715 patients who received FS-LASIK surgery. OBLs were measured and reported as a percentage of the flap area to identify the incidence and extent. Flap creation, which is a modification technique, was performed with 8.1-mm flap diameters plus 0.3-mm enlarged interlamellar photodisruption (group Flap 2.0). The same flap diameters without extra photodisruption as the previous standard setting were also implemented (group Flap 1.0). The preoperative measurements, including sphere, cylinder, keratometry, and intraoperative characteristics such as flap size and thickness, were documented. Possible risk factors for the occurrence of OBLs were investigated in this study.
Results
The incidence of an OBL was reduced when using the Flap 2.0 program (31.4%) compared to the Flap 1.0 program (63.7%). The area of hard and soft OBLs created by the Flap 2.0 program is smaller than those created by the Flap 1.0 program (P = 0.007 and P < 0.001). Multivariate logistic regression indicated that a thinner flap (P = 0.038) and a higher sphere (P = 0.001) affected the chance of hard OBLs occurring.
Conclusion
The VisuMax Flap 2.0 program promotes gas venting by enlarging the interlamellar photodisruption size. The incidence and extent of OBLs appear to be reduced significantly when the Flap 2.0 program is applied.
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Sun L, Jhanji V, Li S, Li J, Ji R, Zeng H, Ng TK, Zhang M, Zhang R. Vector analysis of astigmatic correction after single-step transepithelial photorefractive keratectomy and femtosecond-assisted laser in-situ keratomileusis for low to moderate myopic astigmatism. Indian J Ophthalmol 2022; 70:3483-3489. [PMID: 36190031 PMCID: PMC9789874 DOI: 10.4103/ijo.ijo_649_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Purpose This study aimed to evaluate the outcomes of astigmatic correction by single-step transepithelial photorefractive keratectomy (TransPRK) and femtosecond-assisted laser in-situ keratomileusis (Femto-LASIK) surgeries. Methods A total of 218 subjects received TransPRK or Femto-LASIK surgery for the treatment of myopia and astigmatism (-2.25 to -0.25 D). Refraction errors and uncorrected (UDVA) and corrected distance visual acuity (CDVA) were examined before and at 3 months after surgery. Astigmatism changes were assessed by vector analysis. Results Preoperative parameters of the TransPRK group were similar to the Femto-LASIK group. UDVA and CDVA at 3 months were similar between both groups. Manifest refraction (MR) spherical equivalent in the TransPRK group (0 ± 0.20 D) was slightly lower compared with the Femto-LASIK group at 3 months (0.11 ± 0.25 D, P = 0.001). MR cylinder was -0.06 ± 0.19 D in the TransPRK group and -0.02 ± 0.15 D in the Femto-LASIK group at 3 months (P = 0.135). The index of success (IS) was 0.15 ± 0.36 in the TransPRK group and 0.06 ± 0.17 in the Femto-LASIK group (P = 0.125). The correction index (CI) was 1.03 ± 0.19 in the TransPRK group and 1.01 ± 0.11 in the Femto-LASIK group (P = 0.815). Conclusion For low to moderate myopic astigmatism, TransPRK provided a comparable astigmatic treatment effect as Femto-LASIK. Myopic astigmatism was both slightly overcorrected after TransPRK and Femto-LASIK surgeries.
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Affiliation(s)
- Lixia Sun
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Vishal Jhanji
- UPMC Eye Center, University of Pittsburgh School of Medicine, Pittsburgh, PA, United States
| | - Senmao Li
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Jinyu Li
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Ruifeng Ji
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Hongqiang Zeng
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Tsz Kin Ng
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China
| | - Mingzhi Zhang
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China,Correspondence to: Dr. Mingzhi Zhang, Joint Shantou International Eye Center of Shantou University and the Chinese University of Hongkong, Dong Xia North Road, Shantou, Guangdong Province, China. E-mail:
Dr. Riping Zhang, Joint Shantou International Eye Center of Shantou University and the Chinese University of Hongkong, Dong Xia North Road, Shantou, Guangdong Province, China. E-mail:
| | - Riping Zhang
- Joint Shantou International Eye Center of Shantou University and The Chinese University of Hong Kong, Shantou, Guangdong Province, China,Correspondence to: Dr. Mingzhi Zhang, Joint Shantou International Eye Center of Shantou University and the Chinese University of Hongkong, Dong Xia North Road, Shantou, Guangdong Province, China. E-mail:
Dr. Riping Zhang, Joint Shantou International Eye Center of Shantou University and the Chinese University of Hongkong, Dong Xia North Road, Shantou, Guangdong Province, China. E-mail:
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He X, Li SM, Zhai C, Zhang L, Wang Y, Song X, Wang Y. Flap-making patterns and corneal characteristics influence opaque bubble layer occurrence in femtosecond laser-assisted laser in situ keratomileusis. BMC Ophthalmol 2022; 22:300. [PMID: 35820852 PMCID: PMC9277786 DOI: 10.1186/s12886-022-02524-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2022] [Accepted: 07/07/2022] [Indexed: 11/18/2022] Open
Abstract
Background Opaque bubble layer (OBL), which generates from photo-disruptive procedures on the cornea, has been a common phenomenon during femtosecond laser-assisted refractive surgeries and it would potentially impact eye tracking and flap lifting. And we have observed that an updated flap-making pattern could form less OBL clinically than the traditional pattern, which needed further approval. Thus, the purpose of this study is to prove our observation and investigate the possible risk factors related to the occurrence and type of OBL in laser in situ keratomileusis (LASIK) flaps using the Visumax laser system. Methods This prospective study included 167 eyes of 86 patients (mean age: 27.5 ± 6.1 years) undergoing bilateral femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) for myopia/myopic astigmatism by the same surgeon from April 2020 to August 2020. Preoperative data on refraction, central corneal thickness (CCT), and keratometry as well as intraoperative data were included for analysis. A new flap-making pattern creating an offset between flap-cut and side-cut was adopted to compare with the traditional pattern. The operation video of flap formation was analyzed to identify the existence and type of OBL. The area covered by OBL and the ratio of OBL to flap were calculated using Image J software. Results Among 167 eyes, 54 eyes (32.3%) developed OBLs, consisting of 31 as hard OBL coexisting with soft OBL, and 23 as soft OBL alone. The OBL incidence was significantly reduced in eyes with the new flap-making pattern compared with the traditional pattern (13.8% vs. 52.5%, P < 0.001). Hard OBLs had larger area ratios than soft OBLs (14.3 ± 8.3% vs. 1.1 ± 1.8%, P < 0.001). Univariate analyses revealed that eyes with more myopia, thicker CCT, and traditional flap-making patterns were more likely to develop OBLs. Multivariate analysis further confirmed that more myopia, thicker CCT, and traditional flap-making pattern were risk factors for OBLs. A Larger corneal diameter was associated with a higher incidence of hard OBL when applying the traditional flap-making process. Conclusion More myopia, thicker CCT, and larger corneal diameter were risk factors for OBL development during flap creation, whereas a flap-making pattern with an offset between flap-cut and side-cut could reduce the incidence of OBL.
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Affiliation(s)
- Xi He
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Shi-Ming Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China.
| | - Changbin Zhai
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China.
| | - Li Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Yue Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Xiumei Song
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Yi Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University; Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
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Wan KH, Chan TC, Kwok PS, Ng AL. Combined accelerated collagen crosslinking and sub-Bowman's keratomileusis in high myopic eyes: a comparison between total ultraviolet energy dose. Semin Ophthalmol 2022; 37:676-681. [PMID: 35476818 DOI: 10.1080/08820538.2022.2070026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
AIM To compare the safety, efficacy, and predictability outcomes of combined sub-Bowman's keratomileusis (thin flap laser in situ keratomileusis [LASIK]) and accelerated crosslinking (CXL) using two different irradiation durations. METHODS A retrospective comparative study of patients with percent tissue altered ≥35%, undergoing simultaneous CXL during sub-Bowman's keratomileusis were recruited. Following riboflavin application, they underwent ultraviolet-A (UVA) irradiation (18 mW/cm2) for either 2 min (total energy 2.16 J/cm2) or 3 min (total energy 3.24 J/cm2). Visual and refractive outcomes were compared between follow-up visits during the first year postoperatively. Demarcation line and endothelial cell count were evaluated, respectively, at 1 and 3 months postoperatively. RESULTS The baseline characteristics were similar between the 40 eyes/patients treated using the 2-min protocol and the 33 eyes/patients treated with the 3-min protocol (p ≥ .114). Uncorrected distance visual acuity and corrected distance visual acuity were significantly better for eyes treated with the shorter irradiation protocol on Day 1 (p ≤ .030) and Month 1 (p ≤ .040) postoperatively; these differences diminished by Month 3 (p ≥ .070). Likewise, the efficacy index was higher during the first postoperative week for the 2-min protocol (p ≤ .043). At 1 year, the proportion of eye attaining within 0.5 D of target refraction was 80.0% and 84.8% for the 2-min and 3-min protocols, respectively (p = .590). The corresponding corneal stromal demarcation line depth and endothelial cell density changes were comparable between the two groups (p = .311 and 0.899, respectively). CONCLUSIONS A comparable volume of crosslinked corneal tissue can be achieved by using a shorter UVA irradiation duration. Additional duration of UVA irradiation could lead to delay in visual rehabilitation after simultaneous sub-Bowman's keratomileusis and CXL.
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Affiliation(s)
- Kelvin H Wan
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong
| | - Tommy Cy Chan
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong.,Department of Ophthalmology, Hong Kong Sanatorium and Hospital, Hong Kong
| | | | - Alex Lk Ng
- Hong Kong Ophthalmic Associates, Hong Kong
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14
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Wang C, Li X, Guo Y, He R, Guo H, Chen W. Effects of Laser In Situ Keratomileusis and Small-Incision Lenticule Extraction on Corneal Biomechanical Behavior: A Finite Element Analysis. Front Bioeng Biotechnol 2022; 10:855367. [PMID: 35480973 PMCID: PMC9035518 DOI: 10.3389/fbioe.2022.855367] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2022] [Accepted: 02/21/2022] [Indexed: 11/13/2022] Open
Abstract
Myopia, which is the result of the uncoordinated development of the eyeball, has become a major public health focus worldwide. Laser in situ keratomileusis (LASIK) and small-incision lenticule extraction (SMILE) have been successfully used in modern corneal refractive surgery. However, there are still controversies about postoperative results of LASIK and SMILE. In this study, a three-dimensional finite element model of the cornea was constructed based on the elevation and pachymetry data of a female volunteer. Surgical parameters, magnitudes of myopic correction, and intraocular pressure (IOP) were varied. Furthermore, an iterative algorithm was applied to retrieve the free-stress state of the intact corneal model, LASIK model, and SMILE model. To better evaluate the differences between LASIK and SMILE procedures, the displacement and Von Mises stress on the anterior and posterior corneal surface along the x- and y-axes were analyzed. Results for the zero-pressure model showed larger displacement compared to the image-based corneal model, suggesting that the initial corneal pre-stress stiffens the response of the cornea, both in the intact cornea and under refractive surgery. In addition, the displacement on the corneal surface in LASIK (both zero-pressure and image-based model) was obviously higher than that of the SMILE model. In contrast, SMILE increased Von Mises stress in the corneal cap and reduced Von Mises stress in the residual stromal bed compared with the LASIK model. However, the maximum Von Mises stress in the SMILE model was still smaller than that of the LASIK model. Moreover, the displacement and Von Mises stress on the residual stromal bed increased linearly with IOP. Overall, LASIK and SMILE refractive surgery could change biomechanical behaviors of the cornea. Compared to LASIK refractive surgery, SMILE may present a lower risk of ectasia. Creating a corneal cap rather than a corneal flap may have an advantage in improving corneal biomechanical stability.
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Affiliation(s)
- Chenyan Wang
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Xiaona Li
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
- *Correspondence: Xiaona Li, ; Weiyi Chen,
| | - Yuan Guo
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Rui He
- Department of Excimer Laser, Shanxi Eye Hospital, Taiyuan, China
| | - Hongmei Guo
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Weiyi Chen
- College of Biomedical Engineering, Taiyuan University of Technology, Taiyuan, China
- *Correspondence: Xiaona Li, ; Weiyi Chen,
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15
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Titiyal JS, Kaur M, Nair S. Are Fenestrations in Peripheral Pre-Descemet’s Layer the Route for Intracameral Air Bubble Migration During Femtosecond LASIK? Med Hypotheses 2022. [DOI: 10.1016/j.mehy.2022.110844] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Gros-Otero J, Rodríguez-Pérez I, Teus MA, Katsanos A, Mikropoulos DG, García-González M. Myopic LASIK Outcomes: Comparison of Three Different Femtosecond Lasers and a Mechanical Microkeratome Using the Same Excimer Laser. Ophthalmol Ther 2022; 11:1047-1066. [PMID: 35262896 PMCID: PMC9114235 DOI: 10.1007/s40123-022-00486-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/11/2022] [Indexed: 10/28/2022] Open
Abstract
INTRODUCTION To compare the influence of one microkeratome and three femtosecond lasers on myopic laser in situ keratomileusis (LASIK) outcomes. METHODS Retrospective, observational cohort study. We compared 134 eyes treated with the IntraLase 60 kHz, 112 eyes treated with the Femto LDV Z6, 206 eyes treated with the FS200, and 98 eyes treated with the Hansatome zero compression microkeratome. All eyes were operated on using the same surgical protocol with the same excimer laser (Wavelight Allegretto) and were allocated to refraction-matched groups. RESULTS One day and one week postoperatively, uncorrected distance visual acuity was significantly lower in the FS200 group compared to others (P = 0.0001). This difference disappeared at the 1- and 3-month postoperative visits. Significant differences were found among groups in terms of safety index (P = 0.0001), residual sphere (P = 0.0001), and residual cylinder (P = 0.02) at the 3-month postoperative visit. No significant differences were found in corrected distance visual acuity or efficacy index. CONCLUSION According to our results, a slight delay in visual restoration after FS200 LASIK surgery might be expected. This delay was statistically significant at 1 day and 1 week postoperatively, but there were no differences from the 1-month visit onwards. Additionally, significant differences were found among devices in terms of safety index and the refractive results, which were found not to be clinically relevant.
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Affiliation(s)
| | | | - Miguel A Teus
- Clínica Novovisión, Paseo de la Castellana 54, 28046, Madrid, Spain.,Hospital Universitario "Príncipe de Asturias", University of Alcalá, Alcalá de Henares, Madrid, Spain
| | - Andreas Katsanos
- Department of Ophthalmology, University of Ioannina, Ioannina, Greece
| | - Dimitrios G Mikropoulos
- 3rd University Department of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece
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17
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de Rojas Silva MV, Tobío Ruibal A. New mechanism for epithelial ingrowth after small incision lenticule extraction: Vertical epithelial gas breakthrough. Eur J Ophthalmol 2022; 33:NP78-NP83. [PMID: 35234539 DOI: 10.1177/11206721221083796] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A 41-year-old man underwent SMall Incision Lenticule Extraction (SMILE) to treat myopia in both eyes. The femtosecond procedure was uneventful but a paracentral epithelial blister appeared during the dissection of the anterior plane of the lenticule in the right eye. The posterior surface of the lenticule was dissected without any complication. The surgery of the left eye was uneventful. In the postoperative period, he developed a paracentral epithelial ingrowth in his right eye, exactly underneath the site where the epithelial blister had been noted during the dissection of the lenticule. This induced irregular astigmatism, severely affecting his visual acuity. The decision of surgical treatment was made. After the de-epithelialization of an area of 6mm around the ingrowth, the SMILE incision was opened, and the epithelial ingrowth was dissected and removed from the interface. One month later, uncorrected visual acuity was 20/20, no epithelial ingrowth was observed at the interface, and only the edge of the former ingrowth was barely visible in slit lamp examination. No recurrence was observed. We hypothesize that a vertical epithelial gas breakthrough created a fistula between the interface and the epithelium, forming a pathway for the epithelial cells and giving rise to epithelial ingrowth.
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Affiliation(s)
- Mª Victoria de Rojas Silva
- Victoria de Rojas Instituto Oftalmológico - Policlínica Assistens, A Coruña, Spain.,Department of Ophthalmology, 16811Complexo Hospitalario Universitario A Coruña, Spain
| | - Adrián Tobío Ruibal
- Victoria de Rojas Instituto Oftalmológico - Policlínica Assistens, A Coruña, Spain
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18
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Chang JY, Lin PY, Hsu CC, Liu CJL. Comparison of clinical outcomes of LASIK, Trans-PRK, and SMILE for correction of myopia. J Chin Med Assoc 2022; 85:145-151. [PMID: 34861667 DOI: 10.1097/jcma.0000000000000674] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Transepithelial photorefractive keratectomy (Trans-PRK), laser-assisted in situ keratomileusis (LASIK), and small incision lenticule extraction (SMILE) are three mainstay refractive surgeries worldwide. The applicability, efficacy, safety, and predictability of these different techniques are quite similar. Trans-PRK has the strongest biostability, earliest return to normal corneal sensitivity but the longest recovery time, most uncomfortable postoperative experience, and possibility of corneal haze. LASIK possesses the fastest visual rehabilitation but the slowest corneal nerve reinnervation, and flap displacement is possibly lifelong. SMILE incurs no flap-related complications and has intermediate vision recovery time and biomechanics compared with Trans-PRK and LASIK. However, it lacks the cyclotorsion-compensation system, eye-tracking system, and customized treatment profile for high astigmatism or irregular corneal surface. This review aims to introduce the mechanisms, pros, and cons of these three types of refractive surgery. With full understanding, practitioners could advise patients on the most suitable treatment of choice.
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Affiliation(s)
- Jin-Yu Chang
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Pei-Yu Lin
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
| | - Chih-Chien Hsu
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
| | - Catherine Jui-Ling Liu
- Department of Ophthalmology, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
- School of Medicine, National Yang Ming Chiao Tung University, Taipei, Taiwan, ROC
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19
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Sarkar S, Devi P, Vaddavalli PK, Reddy JC, Bharadwaj SR. Differences in Image Quality after Three Laser Keratorefractive Procedures for Myopia. Optom Vis Sci 2022; 99:137-149. [PMID: 34974458 DOI: 10.1097/opx.0000000000001850] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
SIGNIFICANCE Psychophysical estimates of spatial and depth vision have been shown to be better after bilateral ReLEx small-incision lenticule extraction (SMILE) refractive surgery for myopia, relative to photorefractive keratectomy (PRK) and femtosecond laser-assisted in situ keratomileusis (FS-LASIK). The present study provides the optical basis for these findings using computational image quality analysis. PURPOSE This study aimed to compare longitudinal changes in higher-order wavefront aberrations and image quality before and after bilateral PRK, FS-LASIK, and SMILE refractive procedures for correcting myopia. METHODS Wavefront aberrations and image quality of both the eyes of 106 subjects (n = 40 for FS-LASIK and SMILE and n = 26 for PRK) were determined pre-operatively and at 1-week, 1-month, 3-month, and 6-month post-operative intervals using computational through-focus analysis for a 6-mm pupil diameter. Image quality was quantified in terms of its peak value and its interocular difference, residual defocus that was needed to achieve peak image quality (best focus), and the depth of focus. RESULTS The increase in root mean squared deviations of higher-order aberrations post-operatively was lesser after SMILE (1-month visit median [25th to 75th interquartile range], 0.34 μm (0.28 to 0.39 μm]) than after PRK (0.80 μm [0.74 to 0.87 μm]) and FS-LASIK (0.74 μm [0.59 to 0.83 μm]; P ≤ .001), all relative to pre-operative values (0.20 μm [0.15 to 0.30 μm]). The peak image quality dropped and its interocular difference increased, best focus shifted myopically by 0.5 to 0.75 D, and depth of focus widened significantly after PRK and FS-LASIK surgeries, all relative to pre-operative values (P < .001). All these changes were negligible but statistically significant in a minority of instances after SMILE surgery (P ≥ .01). CONCLUSIONS Although all three refractive surgeries correct myopia, the image quality and its similarity between eyes are better and closer to pre-operative values after SMILE, compared with FS-LASIK and PRK. These results can be explained from the underlying increase in higher-order wavefront aberrations experienced by the eye post-operatively.
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Affiliation(s)
| | | | | | - Jagadesh C Reddy
- The Cornea Institute, L V Prasad Eye Institute, Hyderabad, Telangana, India
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20
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Asena BS, Donmez O. The impact of learning curve on flap thickness outcome in femtosecond laser assisted LASIK performed with new LenSx dual platform. KOREAN JOURNAL OF OPHTHALMOLOGY 2022; 36:202-209. [PMID: 35067019 PMCID: PMC9194732 DOI: 10.3341/kjo.2021.0154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Accepted: 12/30/2021] [Indexed: 11/23/2022] Open
Abstract
Purpose To evaluate the effect of learning curve on flap thickness (FT) outcome in femtosecond (FS) laser-assisted laser in situ keratomileusis (LASIK) operation for myopia performed with recently introduced LenSx dual platform using curved applanation cone. Methods Seventy eyes of 36 patients with myopia or myopic astigmatism operated with FS laser-assisted LASIK with recently introduced LenSx dual platform were evaluated in this retrospective study. Operations were divided into two groups: first 20 operations (20 eyes of 10 patients) and next 50 operations (50 eyes of 26 patients). Data on patient demographics, preoperative and postoperative keratometric and aberrometric parameters, and FT related outcome, including mean central FT, mean total FT, intra-FT range, and FT homogeneity were compared in study groups. Results Except for significantly lower preoperative steepest keratometry values in the next 50 operations versus first 20 operations (p = 0.033), no significant difference was noted between study groups in terms of preoperative and postoperative parameters. When compared to first 20 operations, next 50 operations were associated with significantly higher values for mean central FT (median, 123 μm vs. 114 μm; p = 0.007) and mean total FT (median, 123 μm vs. 113 μm; p = 0.015), whereas significantly lower intra-FT range (median, 4.0 μm vs. 4.5 μm; p = 0.003). Conclusions In conclusion, our findings related to FS laser-assisted LASIK surgery for myopia with new LenSx dual platform using curved applanation cone revealed significant impact of learning curve on the corneal FT outcome in terms of closer FT to the intended value and lower intra-flap range.
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Affiliation(s)
| | - Oya Donmez
- Department of Ophthalmology, Tinaztepe Galen Hospital, Izmir,
Turkey
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21
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Flap Thickness and the Risk of Complications in Mechanical Microkeratome and Femtosecond Laser In Situ Keratomileusis: A Literature Review and Statistical Analysis. Diagnostics (Basel) 2021; 11:diagnostics11091588. [PMID: 34573930 PMCID: PMC8468565 DOI: 10.3390/diagnostics11091588] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2021] [Revised: 08/11/2021] [Accepted: 08/17/2021] [Indexed: 11/16/2022] Open
Abstract
INTRODUCTION A recent Cochrane review found no difference in visual acuity outcomes between femtosecond-assisted laser in situ keratomileusis (LASIK) and LASIK using mechanical microkeratomes (MMKs). This study compares the flap thickness and risk of complications related to flap creation using femtosecond lasers and MMKs. METHODS PubMed and the Web of Science are used to search the medical literature. An extensive search is performed to identify the flap thickness and complications of LASIK as reported up to 15 July 2021. The following keywords are used in various combinations: Corneal flap, femtosecond laser, laser in situ keratomileusis, laser-assisted in situ keratomileusis, LASIK, mechanical microkeratome. RESULTS After removing duplicates and irrelevant studies, 122 articles were included for review. Pooled differences for intended vs. postoperative flap thickness using MMKs and femtosecond laser were -4.07 μm (95% CI: -19.55, 3.24 μm) in studies on the MMK and 5.43 μm (95% CI: 2.30, 7.84 μm; p < 0.001), respectively. After removing the studies evaluating outcomes of the old generation Hansatome MMKs (which had a significantly greater variation of flap thickness), the pooled difference for newer MMKs was 4.97 μm (95% CI: 0.35, 9.58 μm; p < 0.001), but the results still favored the femtosecond laser. Uncommon and mild complications unique for the femtosecond LASIK are epithelial gas breakthrough, opaque bubble layer, transient light sensitivity syndrome, and rainbow glare. A single study reported a very low, but stastically different risk of postoperative flap slippage (0.033% for MMK LASIK, and 0.003% for femtosecond LASIK, respectively). CONCLUSION In both manual microkeratome and femtosecond LASIK, intra- and postoperative complications were uncommon. The evidence of the superiority of one technique in terms of complications over another cannot be indisputably stated.
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22
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Cañones-Zafra R, Katsanos A, Garcia-Gonzalez M, Gros-Otero J, Teus MA. Femtosecond LASIK for the correction of low and high myopic astigmatism. Int Ophthalmol 2021; 42:73-80. [PMID: 34370173 DOI: 10.1007/s10792-021-02001-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Accepted: 08/01/2021] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Higher preoperative myopic astigmatism is associated with a higher probability of retreatment due to patient dissatisfaction as a result of residual cylindrical error. Nonetheless, retreatment is safe and the final clinical results are comparable to those of patients with lower preoperative astigmatism who were satisfied with the primary treatment. Our purpose is to compare the efficacy and safety of femtosecond LASIK (FS-LASIK) for the refractive correction of patients with low (< 1.5 Diopters (D) versus high (≥ 1.5 D) myopic astigmatism. METHODS Retrospective observational study of 841 eyes of 825 eligible patients treated with FSLASIK for the correction of simple or compound myopic astigmatism. Outcome measures included residual error, best corrected and uncorrected distance visual acuity (BCVA and UCVA), efficacy and safety 3 months after the primary procedure or the retreatment. RESULTS Of 841 eyes in total, 432 (51.37%) had < 1.5 D (Group 1) and 409 (48.63%) had ≥ 1.5 D (Group 2) preoperative myopic astigmatism. The efficacy index of primary treatment was 0.94 ± 0.18 in Group 1 and 0.89 ± 0.22 in Group 2 (P = 0.001). Of 138 eyes (16.41%) that were retreated due to dis-satisfaction related to residual refractive error, 28 belonged to Group 1 (6.5%) and 110 (26.9%) to Group 2 (P < 0.001). Following retreatment, small but statistically significant differences in the residual mean postoperative cylinder (-0.08 ± 0.24 vs -0.27 ± 0.46 D, P = 0.001) and UCVA (1.11 vs 0.96, P = 0.0001) were detected for Groups 1 and 2, respectively. However, there were no statistically significant differences in the safety and efficacy indices. CONCLUSION Following FS-LASIK, eyes with myopic astigmatism ≥ 1.5 D have approximately four times more chances of undergoing retreatment due to dis-satisfaction caused by residual refractive error compared to eyes with myopic astigmatism < 1.5 D. However, the clinical results after retreatment are highly satisfactory and comparable in both groups.
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Affiliation(s)
- Rafael Cañones-Zafra
- Department of Ophthalmology, Príncipe de Asturias University Hospital, University of Alcalá, Av. Víctimas del Terrorismo N5, Pl 8, 1ºA, 28805, Alcalá de Henares, Madrid, Spain.
- Clínica Novovisión, Madrid, Spain.
| | - Andreas Katsanos
- Ophthalmology Department, University of Ioannina, Ioannina, Greece
| | - Montserrat Garcia-Gonzalez
- Department of Ophthalmology, Príncipe de Asturias University Hospital, University of Alcalá, Av. Víctimas del Terrorismo N5, Pl 8, 1ºA, 28805, Alcalá de Henares, Madrid, Spain
- Clínica Novovisión, Madrid, Spain
- Clínica Rementería, Madrid, Spain
| | - Juan Gros-Otero
- Clínica Rementería, Madrid, Spain
- San Pablo CEU University, Madrid, Spain
| | - Miguel A Teus
- Department of Ophthalmology, Príncipe de Asturias University Hospital, University of Alcalá, Av. Víctimas del Terrorismo N5, Pl 8, 1ºA, 28805, Alcalá de Henares, Madrid, Spain
- Clínica Novovisión, Madrid, Spain
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A Comparative Study of Laser In Situ Keratomileusis Flaps Created Using Single-Functional Versus Multifunctional Femtosecond Laser for Refractive Surgery. Cornea 2021; 39:1122-1131. [PMID: 32472791 DOI: 10.1097/ico.0000000000002353] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE To compare laser in situ keratomileusis flaps created at the programmed target thickness of 120 μm using the LenSx multifunctional and the FS200 single-functional femtosecond lasers as evaluated by anterior segment optical coherence tomography (AS-OCT). METHODS This was a prospective, comparative, consecutive, blinded, nonrandomized study. Patients with stable refraction for over a year were consecutively allocated to the LenSx group or the FS200 group (n = 66; 33 patients in each group). All the patients underwent refractive surgery in both eyes. Previous eye surgery, ocular pathology associated with refractive errors, pregnancy, breastfeeding, and use of medication that causes ocular adverse effects constituted the exclusion criteria. Corneal topography, corneal tomography, dilated fundoscopy, applanation tonometry, ultrasonic pachymetry, dynamic and static refraction, visual acuity, and AS-OCT were evaluated before and after surgery. AS-OCT flap thickness was measured at 20 points on each cornea. RESULTS In the LenSx group, AS-OCT flap thickness differed significantly from the target thickness at 2 of 20 points (mean differences of 2.106 and 1.803 μm). In the FS200 group, 6 of 20 measurements differed significantly (mean differences ranging from 1.121 to 2.121 μm). The 2 lasers were similarly successful in creating regular and uniform flaps. The agreement between the 2 blinded examiners regarding the AS-OCT flap thickness measurements was excellent (intraclass correlation coefficient >0.75) in both groups. CONCLUSIONS Both femtosecond lasers were safe and capable of creating highly reproducible, uniform, and regular flaps at the target preoperative thickness of 120 μm. The LenSx multifunctional femtosecond laser offers the advantage of allowing both cataract and corneal surgeries.
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Incidence, Risk, and Visual Outcomes after Repositioning of Acute Non-Traumatic Flap Dislocations Following Femtosecond-Assisted LASIK. J Clin Med 2021; 10:jcm10112478. [PMID: 34204958 PMCID: PMC8199895 DOI: 10.3390/jcm10112478] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 05/24/2021] [Accepted: 05/26/2021] [Indexed: 12/20/2022] Open
Abstract
Although the use of femtosecond lasers instead of mechanical devices has decreased the incidence of flap complications following laser-assisted in situ keratomileusis (LASIK), dislocations and striae still occur. Flap repositioning is an effective intervention to improve visual outcomes after acute flap complications in both microkeratome-assisted and femtosecond-assisted LASIK. This retrospective case series included patients undergoing flap repositioning secondary to acute flap dislocation and/or visually significant striae within the first two weeks following femtosecond LASIK (FS-LASIK) from 2015 to 2020 at a single institution. Preoperative, intraoperative, and postoperative de-identified data were analyzed for incidence, risk factors, and visual acuity outcomes. The incidence of flap repositioning was 0.35% in 21,536 eyes (n = 70). Indications for repositioning included acute flap dislocation (35.7%) and visually significant striae (64.3%). High myopia (OR = 3.04, p = 0.001) and patient age over 50 years (OR = 3.69, p = 0.001) were the strongest risk factors for these complications. Prior to flap repositioning, uncorrected distance visual acuity (UDVA) of 20/20 or better and 20/40 or better occurred in 19% and 57% of eyes, respectively. After repositioning, a final UDVA of 20/20 or better and 20/40 or better occurred in 78% and 98% of eyes, respectively. After repositioning, one line of UDVA was lost in two eyes (2.8%) and two lines were lost in one eye (1.4%). Risk factors for acute flap dislocation included high myopia and age over 50 years. Flap repositioning was effective in salvaging visual outcomes.
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Gros-Otero J, Ketabi S, Cañones-Zafra R, Garcia-Gonzalez M, Villa-Collar C, Casado S, Teus MA. Corneal stromal roughness after VisuMax and Intralase femtosecond laser photodisruption: An atomic force microscopy study. PLoS One 2021; 16:e0252449. [PMID: 34043738 PMCID: PMC8158881 DOI: 10.1371/journal.pone.0252449] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 05/16/2021] [Indexed: 11/26/2022] Open
Abstract
Purpose To compare the induced corneal stromal bed roughness measured with atomic force microscopy (AFM) after LASIK flap creation with the IntraLase 60 kHz and the VisuMax femtosecond laser platforms. Methods Three freshly enucleated porcine eyes were operated with each femtosecond laser in this experimental study. Standard LASIK treatment parameters were used for the experiment. After LASIK flap creation, the corneal stromal roughness was assessed using a JPK NanoWizard II® AFM in contact mode immersed in liquid. Olympus OMCL-RC800PSA commercial silicon nitride cantilever tips were used. Surface measurements were made in 10 regions of the central cornea of each sample measuring 20 x 20 microns, at 512 x 512 point resolution. Roughness was measured using the root-mean-square (RMS) value within the given regions. Results Measurements from 30 regions of the 3 eyes (10 measurements per eye) in the Intralase (FS1) group, and 30 regions of the 3 eyes (10 measurements per eye) in the VisuMax (FS2) group were analyzed. There was a statistically significant difference in mean ± standard deviation RMS values between the FS1 and the FS2 groups (360 ± 120 versus 230 ± 100 nm respectively; P< 0.00001). Conclusion This AFM study indicates that the surface of the stromal bed after LASIK flap creation is smoother in the FS2 group than the FS1 group.
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Affiliation(s)
- Juan Gros-Otero
- Clínica Rementería, Madrid, Spain
- Universidad CEU San Pablo, Madrid, Spain
- * E-mail:
| | - Samira Ketabi
- Hospital Universitario Príncipe de Asturias, Alcalá de Henares, Madrid, Spain
| | | | | | | | - Santiago Casado
- IMDEA Nanociencia, Madrid, Spain
- Facultad de Ciencia e Ingeniería de Alimentos, Universidad Técnica de Ambato, Ambato, Ecuador
| | - Miguel A. Teus
- Hospital Universitario Príncipe de Asturias, Alcalá de Henares, Madrid, Spain
- Clínica Novovisión, Madrid, Spain
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Lauzirika G, Garcia-Gonzalez M, Bolivar G, Hernández-Verdejo JL, Blázquez Sánchez V, Gros-Otero J, Teus MA. Measurement of the Intraocular Pressure Elevation During Laser-Assisted In Situ Keratomileusis Flap Creation Using a Femtosecond Laser Platform. Transl Vis Sci Technol 2021; 10:9. [PMID: 34003943 PMCID: PMC7961108 DOI: 10.1167/tvst.10.3.9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2020] [Accepted: 01/25/2021] [Indexed: 11/24/2022] Open
Abstract
Purpose The purpose of this study was to measure the intraocular pressure (IOP) elevation during laser assisted in situ keratomileusis (LASIK) flap creation using the WaveLight FS200 femtosecond (FS) laser platform. Methods We conducted an ex vivo experimental study in an animal model. The WaveLight FS200 FS laser platform was used to perform the corneal LASIK flap in freshly enucleated porcine eyes. We measured the changes in IOP from the application of the suction ring (suctioning phase) through the creation of the lamellar corneal flap (cutting phase). The IOP was recorded using a manometric technique with direct cannulation to the anterior chamber. Results Nine freshly enucleated porcine eyes were included in the study. The mean baseline IOP before the procedure was 20.33 ± 5.9 mm Hg. The mean IOP increase over baseline IOP was 32.33 ± 11.3 mm Hg at the suctioning phase, and 38.22 ± 11.3 mm Hg at the cutting phase. The total surgical time needed to complete the procedure was 29.5 ± 4.4 seconds. Conclusions The WaveLight FS200 FS laser platform produces a low to moderate increase in IOP during LASIK flap creation. Translational Relevance The WaveLight FS200 is a safe FS laser platform because it induces a low to moderate IOP increase during LASIK flap creation.
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Affiliation(s)
- Gorka Lauzirika
- Hospital Universitario Rey Juan Carlos, Móstoles, Madrid, Spain
- Clínica Novovisión, Madrid, Spain
| | | | - Gema Bolivar
- Hospital Universitario Príncipe Asturias, Alcalá de Henares, Madrid, Spain
| | | | | | | | - Miguel A. Teus
- Clínica Novovisión, Madrid, Spain
- Hospital Universitario Príncipe Asturias, Alcalá de Henares, Madrid, Spain
- Universidad de Alcalá, Alcalá de Henares, Madrid, Spain
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Gao H, Miles TP, Troche R, Murdoch DM, Koefoed VF, Cason JB. Quality of Vision Following LASIK and PRK-MMC for Treatment of Myopia. Mil Med 2021; 187:e1051-e1058. [PMID: 33629728 DOI: 10.1093/milmed/usab071] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2020] [Revised: 01/13/2021] [Accepted: 02/09/2021] [Indexed: 11/14/2022] Open
Abstract
INTRODUCTION Femtosecond-assisted thin flap, laser-assisted in situ keratomileusis (LASIK) and photorefractive keratectomy with mitomycin-C (PRK-MMC) are the two most common refractive surgical procedures used to enhance visual capability in the U.S military. The purposes of the study were to examine effects on quality of vision following LASIK and PRK-MMC using a novel computer-based quick contrast sensitivity function (qCSF) test. MATERIALS AND METHODS This prospective clinical study included 58 active duty U.S. military service members who elected LASIK (n = 29) or PRK-MMC (n = 29) refractive surgery for myopia (nearsightedness) treatment. Monocular photopic and mesopic quality of vision of the right eyes in spectacle correction preoperatively and unaided right eyes at four postoperative follow-up visits (1 week, 2 weeks, 1 month, and 3 months) were examined using the qCSF device. Two qCSF parameters, area under a log CSF (AULCSF) between 1.5 and 18 cycles per degree, and CSF cutoff acuity (CSF Acuity), were collected using a 50-trial setting at a 4-m testing distance. General linear model (GLM) Repeated-measures Analysis of Covariance was used to examine effects on quality of vision following LASIK and PRK-MMC. Post hoc testing with Bonferroni correction was used for pairwise comparisons, and preoperative cylinder refraction was used as a covariate. Two-tailed independent t-test was used to compare preoperative and postoperative parameters between LASIK and PRK-MMC. Pearson's correlation, Bland-Altman plots, and multiple linear regression were used to examine the relationship among the qCSF and other vision tests. RESULTS Quality of vision, AULCSF, and CSF Acuity returned to the preoperative baseline at postoperative 2 weeks under mesopic condition and at postoperative 1 month under photopic condition after PRK-MMC. In comparison, photopic and mesopic quality of vision were not significantly different from the baseline at any of the four postoperative visits following LASIK. Changes of CSF Acuity from the baseline after LASIK were significantly better under photopic than mesopic condition by 0.067 ± 0.014 logarithm of the minimum angle of resolution (logMAR); P < .001). Quality of vision was not significantly different between the LASIK and PRK-MMC groups at postoperative 1 and 3 months. When predicting photopic AULCSF (overall model fit R2 = 0.47), 5% contrast acuity (beta = -0.43), visual acuity in 100% contrast (beta = -0.18), and residual refraction in spherical equivalent (beta = 0.20) were significant predictors (P ≤ .001), while high-order aberrations (beta = -0.07, P = .22) were not significant predictors. Visual acuity (beta = -0.12, P = .07) and high-order aberrations (beta = -0.04, P = .58) were not significant predictors of mesopic AULCSF. Bland-Altman plots show that photopic CSF Acuity and visual acuity had a mean difference of 0.19 ± 0.01 logMAR with limits of agreement (LOAs) at -0.01 and 0.39 logMAR. Photopic CSF Acuity and 5% contrast acuity had a mean difference of -0.06 ± 0.01 logMAR with LOAs at -0.33 and 0.21 logMAR. CONCLUSION Quality of vision recovers at postoperative 1 week after LASIK and at postoperative 1 month after PRK-MMC. The standard black-on-white high-contrast, chart-based visual acuity test is weak in predicting quality of vision. The qCSF detects mild-to-moderate visual changes and is suitable for quality of vision assessment following refractive eye surgery.
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Affiliation(s)
- Hong Gao
- Tri-Service Vision Conservation & Readiness Program, Army Public Health Center, Aberdeen Proving Ground, MD 21010-5403, USA
| | - Tyler P Miles
- Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA
| | - Ray Troche
- Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA
| | - Donna M Murdoch
- Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA
| | - Vilhelm F Koefoed
- Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA.,Norwegian Armed Forces, Joint Medical Services, Department of Global Public Health and Primary Care, University of Bergen Faculty of Medicine and Dentistry, Bergen, Norway
| | - John B Cason
- Navy Refractive Surgery Center, Naval Medical Center San Diego, San Diego, CA 92134, USA
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Sioufi K, Zheleznyak L, MacRae S, Rocha KM. Femtosecond Lasers in Cornea & Refractive Surgery. Exp Eye Res 2021; 205:108477. [PMID: 33516763 DOI: 10.1016/j.exer.2021.108477] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 01/20/2021] [Accepted: 01/22/2021] [Indexed: 11/18/2022]
Abstract
Since the introduction of femtosecond laser (FS) systems for corneal flap creation in laser-assisted in-situ keratomileusis there have been numerous applications for FS laser in corneal surgery. This manuscript details the utility of FS lasers in corneal surgical procedures including refractive laser surgeries, intracorneal ring segment tunnels, presbyopic treatments, and FS-assisted keratoplasty. We also review the role of FS lasers in diagnostic procedures such as two photon excitation fluorescence and second harmonic generation.
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Affiliation(s)
- Kareem Sioufi
- Storm Eye Institute, Medical University of South Carolina, Charleston, SC, USA
| | | | - Scott MacRae
- Flaum Eye Institute and the Institute of Optics, University of Rochester, Rochester, NY, USA
| | - Karolinne M Rocha
- Storm Eye Institute, Medical University of South Carolina, Charleston, SC, USA.
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Effect of flap homogeneity on higher-order aberrations induction after femtosecond LASIK for myopia. J Cataract Refract Surg 2020; 46:1278-1283. [PMID: 32898096 DOI: 10.1097/j.jcrs.0000000000000255] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To assess the relevance of the homogeneity of femtosecond laser flap thickness regarding induction of higher-order aberrations (HOAs). SETTING Clínica Rementería & Clínica Novovisión, Madrid, Spain. DESIGN Prospective observational study. METHODS Two hundred thirty-one patients underwent in situ keratomileusis using 5 different femtosecond lasers. The flap thicknesses were measured using anterior segment optical coherence tomography 3 months postoperatively. The same masked observer measured 6 symmetrical points nasally and temporally 1.0 mm, 2.0 mm, and 3.0 mm from the center of the flap in each case. HOAs induced in the cornea were measured using tomography. RESULTS Positive and significant correlations were found between HOA induction and the flap thickness heterogeneity 3.0 mm from the center of the flap. Pearson correlation coefficients for the induction of HOAs were third-order 0.17112 (P = .0224), fourth-order 0.22474 (P = .0026), fifth-order 0.16449 (P = .0282), coma-like 0.17370 (P = .0204), and total HOAs 0.18182 (P = .0151). CONCLUSIONS The amount of flap-thickness heterogeneity at 3.0 mm from the center of the flap created using femtosecond lasers was correlated with the magnitude of the HOAs induced.
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Han SB, Liu YC, Mohamed-Noriega K, Mehta JS. Application of Femtosecond Laser in Anterior Segment Surgery. J Ophthalmol 2020; 2020:8263408. [PMID: 32351726 PMCID: PMC7171667 DOI: 10.1155/2020/8263408] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 03/12/2020] [Indexed: 11/24/2022] Open
Abstract
Femtosecond laser (FSL) is a near-infrared laser that can create reliable and reproducible tissue cutting with minimal damage to adjacent tissue. As the laser can also create incisions with various orientations, depths, and shapes, it is expected to be a useful tool for anterior segment surgery, such as cornea, refractive, and cataract surgery. In this review, the authors will introduce the application of FSL in various anterior segment surgeries and discuss the results of studies regarding the efficacy and safety of FSL in cornea, refractive, and cataract surgery. Experimental studies regarding the potential use of FSL will also be introduced. The studies discussed in this review suggest that FSL may be a useful tool for improving the prognosis and safety of surgeries of the anterior segment.
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Affiliation(s)
- Sang Beom Han
- Department of Ophthalmology, Kangwon National University Hospital, Kangwon National University School of Medicine, Chuncheon, Republic of Korea
| | - Yu-Chi Liu
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Karim Mohamed-Noriega
- Department of Ophthalmology, University Hospital, Faculty of Medicine, Autonomous University of Nuevo Leon, Monterrey, Mexico
| | - Jodhbir S. Mehta
- Singapore National Eye Centre, Singapore
- Singapore Eye Research Institute, Singapore
- Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore
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Kahuam-López N, Navas A, Castillo-Salgado C, Graue-Hernandez EO, Jimenez-Corona A, Ibarra A. Laser-assisted in-situ keratomileusis (LASIK) with a mechanical microkeratome compared to LASIK with a femtosecond laser for LASIK in adults with myopia or myopic astigmatism. Cochrane Database Syst Rev 2020; 4:CD012946. [PMID: 32255519 PMCID: PMC7137867 DOI: 10.1002/14651858.cd012946.pub2] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Laser-assisted in-situ keratomileusis (LASIK) is a surgical procedure that corrects refractive errors. This technique creates a flap of the outermost parts of the cornea (epithelium, bowman layer, and anterior stroma) to expose the middle part of the cornea (stromal bed) and reshape it with excimer laser using photoablation. The flaps can be created by a mechanical microkeratome or a femtosecond laser. OBJECTIVES To compare the effectiveness and safety of mechanical microkeratome versus femtosecond laser in LASIK for adults with myopia. SEARCH METHODS We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 2); Ovid MEDLINE; Embase; PubMed; LILACS; ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We used no date or language restrictions. We searched the reference lists of included trials. We searched the electronic databases on 22 February 2019. SELECTION CRITERIA We included randomized controlled trials (RCTs) of LASIK with a mechanical microkeratome compared to a femtosecond laser in people aged 18 years or older with more than 0.5 diopters of myopia or myopic astigmatism. DATA COLLECTION AND ANALYSIS We used standard methodological procedures expected by Cochrane. MAIN RESULTS We included 16 records from 11 trials enrolling 943 adults (1691 eyes) with spherical or spherocylindrical myopia, who were suitable candidates for LASIK. Five hundred and forty-seven participants (824 eyes) received LASIK with a mechanical microkeratome and 588 participants (867 eyes) with a femtosecond laser. Each trial included between nine and 360 participants. In six trials, the same participants received both interventions. Overall, the trials were at an uncertain risk of bias for most domains. At 12 months, data from one trial (42 eyes) indicates no difference in the mean uncorrected visual acuity (logMAR scale) between LASIK with a mechanical microkeratome and LASIK with a femtosecond laser (mean difference (MD) -0.01, 95% confidence interval (CI) -0.06 to 0.04; low-certainty evidence). Similar findings were observed at 12 months after surgery, regarding participants achieving 0.5 diopters within target refraction (risk ratio (RR) 0.97, 95% CI 0.85 to 1.11; 1 trial, 79 eyes; low-certainty evidence) as well as mean spherical equivalent of the refractive error 12 months after surgery (MD 0.09, 95% CI -0.01 to 0.19; 3 trials, 168 eyes [92 participants]; low-certainty evidence). Based on data from three trials (134 eyes, 66 participants), mechanical microkeratome was associated with lower risk of diffuse lamellar keratitis compared with femtosecond laser (RR 0.27, 95% CI 0.10 to 0.78; low-certainty evidence). Thus, diffuse lamellar keratitis was a more common adverse event with femtosecond laser than with mechanical microkeratome, decreasing from an assumed rate of 209 per 1000 people in the femtosecond laser group to 56 per 1000 people in the mechanical microkeratome group. Data from one trial (183 eyes, 183 participants) indicates that dry eye as an adverse event may be more common with mechanical microkeratome than with femtosecond laser, increasing from an assumed rate of 80 per 1000 people in the femtosecond laser group to 457 per 1000 people in the mechanical microkeratome group (RR 5.74, 95% CI 2.92 to 11.29; low-certainty evidence). There was no evidence of a difference between the two groups for corneal haze (RR 0.33, 95% CI 0.01 to 7.96; 1 trial, 43 eyes) and epithelial ingrowth (RR 1.04, 95% CI 0.11 to 9.42; 2 trials, 102 eyes [50 participants]). The certainty of evidence for both outcomes was very low. AUTHORS' CONCLUSIONS Regarding the visual acuity outcomes, there may be no difference between LASIK with mechanical microkeratome and LASIK with femtosecond laser. Dry eye and diffuse lamellar keratitis are likely adverse events with mechanical microkeratome and femtosecond laser, respectively. The evidence is uncertain regarding corneal haze and epithelial ingrowth as adverse events of each intervention. The limited number of outcomes reported in the included trials, some with potentially significant risk of bias, makes it difficult to draw a firm conclusion regarding the effectiveness and safety of the interventions investigated in this review.
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Affiliation(s)
- Nicolás Kahuam-López
- Universidad Anáhuac México, Campus Norte, Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Av. Universidad Anáhuac 46, Huixquilucan, Mexico, Mexico, 52786
- Instituto de Oftalmología Fundación Conde de Valenciana, Cornea and Refractive Surgery Department, Chimalpopoca 14, Mexico City, Mexico City, Mexico, 06800
| | - Alejandro Navas
- Instituto de Oftalmología Fundación Conde de Valenciana, Cornea and Refractive Surgery Department, Chimalpopoca 14, Mexico City, Mexico City, Mexico, 06800
| | - Carlos Castillo-Salgado
- Johns Hopkins Bloomberg School of Public Health, Department of Epidemiology, 615 N. Wolfe Street, Room E-6136, Baltimore, Maryland, USA, 21205
| | - Enrique O Graue-Hernandez
- Instituto de Oftalmología Fundación Conde de Valenciana, Cornea and Refractive Surgery Department, Chimalpopoca 14, Mexico City, Mexico City, Mexico, 06800
| | - Aida Jimenez-Corona
- Instituto de Oftalmología Fundación Conde de Valenciana, Ocular Epidemiology and Visual Sciences Department, Chimalpopoca 14 Col Obrera del Cuauhtemoc, Mexico City, Mexico, 06800
| | - Antonio Ibarra
- Universidad Anáhuac México, Campus Norte, Centro de Investigación en Ciencias de la Salud (CICSA), Facultad de Ciencias de la Salud, Av. Universidad Anáhuac 46, Huixquilucan, Mexico, Mexico, 52786
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Lim DH, Hyun J, Shin E, Ko BW, Chung ES, Chung TY. Incidence and Risk Factors of Opaque Bubble Layer Formation According to Flap Thickness During 500-kHz FS-LASIK. J Refract Surg 2020; 35:583-589. [PMID: 31498416 DOI: 10.3928/1081597x-20190814-01] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 08/14/2019] [Indexed: 11/20/2022]
Abstract
PURPOSE To present the incidence, risk factors, and effect of opaque bubble layer (OBL) formation during flap creation in laser-assisted in situ keratomileusis (LASIK) with a 500-kHz femtosecond laser on visual performance. METHODS In this retrospective study, preoperative characteristics (age, sex, keratometric value, spherical equivalent, and central corneal thickness) and intraoperative surgical factors (used energy, docking type, and flap thickness) were compared between eyes with and without OBL formation during flap creation. Possible risk factors for specific types of OBLs were analyzed. RESULTS One hundred thirty-five eyes of 71 patients underwent LASIK, and OBL developed in 98 eyes (72.59%). In the univariate analysis, the greater than 80-µm flap group was associated with a lower OBL occurrence than the 80-µm flap group (P = .0424, odds ratio [OR] = 0.481) and hard docking was associated with increased OBL formation (P = .0001, OR = 6.859). In the multivariate analysis, hard docking was a risk factor for OBL development (P = .0003, OR = 6.329). In the subgroup analysis, hard docking had a marginal effect on OBL occurrence in the 80-µm flap group (P = .086, OR = 3.564), but it had a strong effect in the greater than 80-µm flap group (P = .0018, OR = 10.210). CONCLUSIONS Hard docking is a risk factor for OBL development. However, hard docking had a small effect on OBL occurrence in the 80-µm flap group during LASIK. OBL formation did not affect visual performance. [J Refract Surg. 2019;35(9):583-589.].
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Application of the SMILE-derived lenticule in therapeutic keratoplasty. Int Ophthalmol 2019; 40:689-695. [PMID: 31754892 DOI: 10.1007/s10792-019-01229-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2019] [Accepted: 11/16/2019] [Indexed: 10/25/2022]
Abstract
PURPOSE To observe the clinical efficacy of the small incision lenticule extraction (SMILE)-derived lenticule patch graft in therapeutic keratoplasty, especially for the treatment of corneal microperforation or partial-thickness corneal defects. METHODS Corneal lenticule obtained from SMILE surgery with diameter greater than 6.5 mm and thickness greater than 100 μm was preserved in a balanced salt solution (Alcon Laboratories, Fort Worth, TX) containing 50 mg/mL penicillin, 50 mg/mL streptomycin, 100 mg/mL neomycin, and 2.5 mg/mL amphotericin for at least 3 months. Preoperatively, anterior segment optical coherence tomography was used to assess the depth of the ulcer and to decide the thickness of the lenticule. Patients were followed up on day 1 and then at 1, 3, and 6 months postoperatively. RESULTS Corneal perforation or defects were successfully patched in all 17 eyes; 8 eyes (47%) exhibited improvement postoperative corrected distance visual acuity. During the follow-up period of 6 months, there was no evidence of infection, relapse, or perforation detected in all eyes. Lenticule grafts were attached by graft beds very well and remain clear through to the last follow-up checkup in all eyes treated. CONCLUSIONS The lenticule patch graft seems to serve as a safe, feasible, and inexpensive surgical option for the treatment of keratohelcosis or partial-thickness corneal defects, especially in small perforation and defects. There are hopeful signs that SMILE-derived lenticule becomes a potential graft for therapeutic keratoplasty.
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Gros-Otero J, Ketabi S, Cañones-Zafra R, Garcia-Gonzalez M, Parafita-Fernandez A, Villa-Collar C, Casado S, Teus M. Analysis of corneal stromal roughness after iFS 150 kHz and LenSx femtosecond LASIK flap creation in porcine eyes. Graefes Arch Clin Exp Ophthalmol 2019; 257:2665-2670. [PMID: 31650272 DOI: 10.1007/s00417-019-04497-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2019] [Revised: 09/20/2019] [Accepted: 09/23/2019] [Indexed: 10/25/2022] Open
Abstract
PURPOSE To describe and compare the stromal bed roughness obtained after laser in situ keratomileusis (LASIK) flap creation using a corneal femtosecond laser platform (iFS 150) and a "dual" femtosecond (FS) laser platform (LenSx). METHODS This ex vivo experimental study was conducted in an animal model using 12 freshly enucleated porcine eyes, six with each femtosecond laser. The standard laser treatment parameters were used for the experiment. After LASIK flap creation, the corneal stromal roughness was assessed using atomic force microscopy (AFM) in contact mode immersed in liquid. In each sample, surface measurements were obtained in 60 regions of six eyes per FS laser in 10 20 × 20-micron areas of the central corneal stroma at 512 × 512-point resolution. The surface roughness was measured and the root-mean-square (RMS) values of the roughness were obtained. RESULTS The mean RMS ± standard deviation values were 430 ± 150 nm for the corneal femtosecond laser platform and 370 ± 100 nm for the dual FS laser platform (P < 0.011). CONCLUSIONS In this experimental study with AFM, we found smoother stromal beds after LASIK flap creation with LenSx compared to iFS 150 kHz. Further studies are needed to understand visual implications of the differences found.
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Affiliation(s)
- Juan Gros-Otero
- Clínica Rementería, Calle Almagro, 36, 28010, Madrid, Spain. .,Universidad CEU San Pablo, Madrid, Spain.
| | - Samira Ketabi
- Hospital Universitario Príncipe de Asturias, Madrid, Spain
| | | | - Montserrat Garcia-Gonzalez
- Clínica Rementería, Calle Almagro, 36, 28010, Madrid, Spain.,Clínica Novovisión, Madrid, Spain.,Universidad Europea de Madrid, Madrid, Spain
| | | | | | - Santiago Casado
- Facultad de Ciencia e Ingeniería de Alimentos, Universidad Técnica de Ambato, Ambato, Ecuador.,IMDEA Nanociencia, Madrid, Spain
| | - Miguel Teus
- Hospital Universitario Príncipe de Asturias, Madrid, Spain.,Clínica Novovisión, Madrid, Spain
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Saerchen E, Liedtke-Gruener S, Kopp M, Heisterkamp A, Lubatschowski H, Ripken T. Femtosecond laser induced step-like structures inside transparent hydrogel due to laser induced threshold reduction. PLoS One 2019; 14:e0222293. [PMID: 31527880 PMCID: PMC6748420 DOI: 10.1371/journal.pone.0222293] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 08/26/2019] [Indexed: 11/26/2022] Open
Abstract
In the area of laser material processing, versatile applications for cutting glasses and transparent polymers exist. However, parasitic effects such as the creation of step-like structures appear when laser cutting inside a transparent material. To date, these structures were only described empirically. This work establishes the physical and chemical mechanisms behind the observed effects and describes the influence of process and material parameters onto the creation of step-like structures in hydrogel, Dihydroxyethylmethacrylat (HEMA). By focusing laser pulses in HEMA, reduced pulse separation distance below 50 nm and rise in pulse energy enhances the creation of unintended step-like structures. Spatial resolved Raman-spectroscopy was used to measure the laser induced chemical modification, which results into a reduced breakdown threshold. The reduction in threshold influences the position of optical breakdown for the succeeding laser pulses and consequently leads to the step-like structures. Additionally, the experimental findings were supplemented with numerical simulations of the influence of reduced damage threshold onto the position of optical breakdown. In summary, chemical material change was defined as cause of the step-like structures. Furthermore, the parameters to avoid these structures were identified.
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Affiliation(s)
- Emanuel Saerchen
- Laser Zentrum Hannover e.V., Hannover, Germany
- Rowiak GmbH, Hannover, Germany
| | | | | | - Alexander Heisterkamp
- Laser Zentrum Hannover e.V., Hannover, Germany
- Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Hannover, Germany
| | - Holger Lubatschowski
- Rowiak GmbH, Hannover, Germany
- Institut fuer Quantenoptik, Leibniz Universitaet Hannover, Hannover, Germany
| | - Tammo Ripken
- Laser Zentrum Hannover e.V., Hannover, Germany
- * E-mail:
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Bolivar G, Garcia-Gonzalez M, Laucirika G, Villa-Collar C, Teus MA. Intraocular pressure rises during laser in situ keratomileusis: Comparison of 3 femtosecond laser platforms. J Cataract Refract Surg 2019; 45:1172-1176. [DOI: 10.1016/j.jcrs.2019.03.013] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2019] [Revised: 02/20/2019] [Accepted: 02/20/2019] [Indexed: 11/29/2022]
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Alvarez MT, Montesel A, Bataille L. Late traumatic flap dislocation seven years after femtosecond laser-assisted in situ keratomileusis. Int J Ophthalmol 2019; 12:862-865. [PMID: 31131251 DOI: 10.18240/ijo.2019.05.27] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 12/13/2018] [Indexed: 11/23/2022] Open
Affiliation(s)
- María T Alvarez
- Cataract and Refractive Surgery Department, VISSUM, Madrid 28035, Spain.,Research and Development Department, VISSUM, Alicante 03016, Spain
| | - Andrea Montesel
- Research and Development Department, VISSUM, Alicante 03016, Spain
| | - Laurent Bataille
- Research and Development Department, VISSUM, Alicante 03016, Spain
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Wei CH, Dai QY, Mei LX, Ge Y, Zhang PF, Song E. Paired eye-control study of unilateral opaque bubble layer in femtosecond laser assisted laser in situ keratomileusis. Int J Ophthalmol 2019; 12:654-659. [PMID: 31024822 DOI: 10.18240/ijo.2019.04.21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 10/19/2018] [Indexed: 11/23/2022] Open
Abstract
AIM To investigate the predictive factors of the opaque bubble layer (OBL) compared to the fellow eye of same patients in FS200 femtosecond laser assisted laser in situ keratomileusis (FS-LASIK). METHODS This study consisted of 60 consecutive patients (120 eyes) with unilateral OBL during FS-LASIK. Eyes were divided into OBL (the OBL eyes) and OBL-free groups (the fellow eyes) based on the occurrence of OBL. The preoperative demographic data, refraction, keratometry, corneal astigmatism, pachymetry, intraocular pressure and intraoperative data including the outlet location of gas diffusing canal were collected. Conditional logistic regression analysis was performed to find the associated factors with OBL in the two groups by determining odds ratios (OR) and 95%CI. RESULTS The preoperative demographic data, mean spherical errors, mean K value, suction time, intraocular pressure and central cornea thickness were not significantly different between the two groups. The outlet location of gas diffusing canal (P<0.01, OR 7.16, 95%CI 2.53-20.32) and the corneal astigmatism (P=0.013, OR 0.13, 95%CI 0.03-0.65) were significantly associated with the incidence of OBL by multivariate logistic regression analysis. Visual acuity, efficacy, and safety were comparable between the two groups two months after surgery except for a slightly lower predictability value for the hard OBL eyes. CONCLUSION The reduction of the incidence of OBL is obvious when the outlet of gas diffusing canal located at the posterior border of the corneoscleral limbus. This is probably consequent to more effectiveness of gas diffusing canal. Corneal astigmatism is also an independent protective factor for OBL formation.
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Affiliation(s)
- Cheng-Hua Wei
- Department of Ophthalmology, the Second Affiliated Hospital of Soochow University, Suzhou 215004, Jiangsu Province, China.,Department of Ophthalmology, the First Affiliated Hospital of Wannan Medical College, Wuhu 241000, Anhui Province, China
| | - Qiao-Yun Dai
- Department of Ophthalmology, the First Affiliated Hospital of Wannan Medical College, Wuhu 241000, Anhui Province, China
| | - Li-Xin Mei
- Department of Ophthalmology, the First Affiliated Hospital of Wannan Medical College, Wuhu 241000, Anhui Province, China
| | - Yao Ge
- Department of Ophthalmology, the First Affiliated Hospital of Wannan Medical College, Wuhu 241000, Anhui Province, China
| | - Peng-Fei Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Wannan Medical College, Wuhu 241000, Anhui Province, China
| | - E Song
- Department of Ophthalmology, Lixiang Eye Hospital of Soochow University, Suzhou 215021, Jiangsu Province, China
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Bandage Contact Lens Application Reduces Fibrotic Wound Healing of Flap Margins after FS-LASIK: A Prospective Randomized Clinical Trial. J Ophthalmol 2019; 2019:3074659. [PMID: 30733872 PMCID: PMC6348804 DOI: 10.1155/2019/3074659] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 12/12/2018] [Indexed: 11/17/2022] Open
Abstract
Purpose To assess the efficacy of applying bandage contact lens (BCL) in reducing the fibrotic healing response of flap margins following femtosecond laser in situ keratomileusis (FS-LASIK). Methods In this prospective, randomized, interventional, observer-masked trial, 41 patients (82 eyes) with myopia and/or myopic astigmatism were scheduled to undergo FS-LASIK. After surgery, patients were fitted with a BCL in one eye (BCL eyes, n=41) but not in the contralateral eye (control eyes, n=41), following randomized allocation of the BCL to the left or right eye of each patient. The BCL was left in place overnight and removed the following morning. All eyes subsequently received standardized postoperative treatments. Patients were followed up for 6 months. We evaluated patients' self-reported postoperative symptom scores for pain, photophobia, tearing, and foreign-body sensation. At 6 months after surgery, we examined the corneal flap margin and adjacent regions, and photographed them using slit-lamp biomicroscopy, to subjectively evaluate the wound healing response. Results Postoperative pain and photophobia were milder in the BCL group than in the control group (P=0.041 and P=0.003, respectively), but patients felt more foreign-body sensation in the eye with a BCL than in the control eye (P=0.001). There was no significant difference in tearing score between BCL eyes and control eyes (P=0.118). Regarding the fibrotic healing response of the flap margin, control eyes showed a wide, bright peripheral circumferential band with a spiculated edge and high reflectivity; conversely, BCL eyes showed a markedly narrower and smoother peripheral circumferential band, with a less spiculated edge and lower reflectivity (P < 0.001). Conclusion Patients felt less discomfort in eyes treated with a BCL after FS-LASIK than in control eyes. BCL-treated eyes also had a less intense wound healing response at the flap margins than control eyes in some of patients. BCLs may merit consideration as a treatment option after FS-LASIK for special patients. This trial is registered with ChiCTR1800016579.
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Ganesh S, Brar S, K V M. CIRCLE Software for the Management of Retained Lenticule Tissue Following Complicated SMILE Surgery. J Refract Surg 2019; 35:60-65. [PMID: 30633789 DOI: 10.3928/1081597x-20181120-01] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Accepted: 11/29/2018] [Indexed: 11/20/2022]
Abstract
PURPOSE To describe the therapeutic use of CIRCLE software (Carl Zeiss Meditec, Jena, Germany) for the management of retained lenticule tissue after complicated small incision lenticule extraction (SMILE). METHODS Two patients were referred for consultation and treatment due to intraoperative complications during SMILE. In case 1, a black patch during laser delivery caused the lenticule to be torn irregularly from the undersurface during extraction and a sliver of it was retained in the pocket. Case 2 presented with false plane dissection and a completely retained lenticule on anterior segment optical coherence tomography. Both cases were managed using the CIRCLE software by converting the cap into a flap, thus making access to the interface possible. RESULTS In case 1, after lifting the flap a small sliver of tissue was found in the interface, which was dissected, following which a 20-µm phototherapeutic keratectomy was done to smooth the interface. In case 2, after lifting the flap the edge of the retained lenticule was identified by using an endoilluminator and the lenticule was separated and subsequently removed. Both cases showed significant improvement in uncorrected distance visual acuity, corrected distance visual acuity, and Objective Scatter Index score on day 1 after repair surgery. CONCLUSIONS CIRCLE software may be successfully used for managing retained lenticule tissue apart from performing enhancement after SMILE. [J Refract Surg. 2019;35(1):60-65.].
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Smolková B, Uzhytchak M, Lynnyk A, Kubinová Š, Dejneka A, Lunov O. A Critical Review on Selected External Physical Cues and Modulation of Cell Behavior: Magnetic Nanoparticles, Non-thermal Plasma and Lasers. J Funct Biomater 2018; 10:jfb10010002. [PMID: 30586923 PMCID: PMC6463085 DOI: 10.3390/jfb10010002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 12/13/2018] [Accepted: 12/21/2018] [Indexed: 12/18/2022] Open
Abstract
Physics-based biomedical approaches have proved their importance for the advancement of medical sciences and especially in medical diagnostics and treatments. Thus, the expectations regarding development of novel promising physics-based technologies and tools are very high. This review describes the latest research advances in biomedical applications of external physical cues. We overview three distinct topics: using high-gradient magnetic fields in nanoparticle-mediated cell responses; non-thermal plasma as a novel bactericidal agent; highlights in understanding of cellular mechanisms of laser irradiation. Furthermore, we summarize the progress, challenges and opportunities in those directions. We also discuss some of the fundamental physical principles involved in the application of each cue. Considerable technological success has been achieved in those fields. However, for the successful clinical translation we have to understand the limitations of technologies. Importantly, we identify the misconceptions pervasive in the discussed fields.
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Affiliation(s)
- Barbora Smolková
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
| | - Mariia Uzhytchak
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
| | - Anna Lynnyk
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
| | - Šárka Kubinová
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
- Institute of Experimental Medicine of the Czech Academy of Sciences, 14220 Prague, Czech Republic.
| | - Alexandr Dejneka
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
| | - Oleg Lunov
- Institute of Physics of the Czech Academy of Sciences, 18221 Prague, Czech Republic.
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Parafita-Fernández A, García-Gonzalez M, Katsanos A, Gros-Otero J, Teus M. Two Femtosecond Laser LASIK Platforms: Comparison of Evolution of Visual Acuity, Flap Thickness, and Stromal Optical Density. Cornea 2018; 38:98-104. [DOI: 10.1097/ico.0000000000001784] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Piñero DP, Teus MA. Clinical outcomes of small-incision lenticule extraction and femtosecond laser-assisted wavefront-guided laser in situ keratomileusis. J Cataract Refract Surg 2018; 42:1078-93. [PMID: 27492109 DOI: 10.1016/j.jcrs.2016.05.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 02/15/2016] [Accepted: 02/16/2016] [Indexed: 12/11/2022]
Abstract
UNLABELLED Small-incision lenticule extraction and wavefront-guided femtosecond-assisted laser in situ keratomileusis (LASIK) provide good visual outcomes and an efficacious correction of myopia or myopic astigmatism with similar levels of safety. Some differences in predictability and the percentage of eyes gaining lines of corrected distance visual acuity are present. A higher level of coma is present after small-incision lenticule extraction, with no clear differences between techniques in spherical aberration. Better contrast sensitivity is achieved in the early postoperative period after wavefront-guided femtosecond laser-assisted LASIK, possibly because of less intrastromal light backscattering and Bowman layer microdistortions. Corneal sensitivity decreased less after small-incision lenticule extraction because of less severe decrease in subbasal nerve density, which has a significant effect on symptomatology and dry-eye tests (P < .05). Significant corneal biomechanical changes occurred after both techniques (P < .05), with no scientific evidence supporting the superiority of 1 technique over the other. FINANCIAL DISCLOSURE Dr. Piñero received an unrestricted educational grant from Abbott Medical Optics, Inc. Neither author has a financial or proprietary interest in any material or method mentioned.
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Affiliation(s)
- David P Piñero
- From the Department of Optics, Pharmacology, and Anatomy, University of Alicante, the Department of Ophthalmology, Vithas Medimar International Hospital, and the Foundation for Visual Quality (Piñero), Alicante; the Hospital Universitario "Príncipe de Asturias," Alcalá de Henares, the Universidad de Alcalá, Alcalá de Henares, and the Novovision Clinic (Teus), Madrid, Spain.
| | - Miguel A Teus
- From the Department of Optics, Pharmacology, and Anatomy, University of Alicante, the Department of Ophthalmology, Vithas Medimar International Hospital, and the Foundation for Visual Quality (Piñero), Alicante; the Hospital Universitario "Príncipe de Asturias," Alcalá de Henares, the Universidad de Alcalá, Alcalá de Henares, and the Novovision Clinic (Teus), Madrid, Spain
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Visual and Refractive Outcomes After Sub-Bowman Keratomileusis and Transepithelial Photorefractive Keratectomy for Myopia. Eye Contact Lens 2018; 45:132-136. [PMID: 30067519 DOI: 10.1097/icl.0000000000000533] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To compare the visual and refractive outcomes of transepithelial photorefractive keratectomy (Trans-PRK) and sub-Bowman femtosecond-assisted laser in situ keratomileusis (SBK). SETTING University hospital. DESIGN Retrospective, comparative study. METHODS Two hundred forty patients with myopia and myopic astigmatism underwent SBK (n=157) or Trans-PRK (n=83). The main outcome measures included manifest spherical equivalent refraction (MRSE), logarithm of the minimum angle of resolution uncorrected visual acuity (UCVA), and best-corrected visual acuity (BCVA), which were evaluated at 1 and 3 months postoperatively. RESULTS The preoperative mean MRSE was -4.00±1.2 diopters (D) and -4.05±1.36 D (P=0.76) in Trans-PRK and SBK groups, respectively. There was a significant improvement in UCVA after Trans-PRK (1.29-0.00 at 1 month and -0.05 at 3 months; P<0.001 for both) and SBK (1.25 to -0.04 at 1 month and -0.05 at 3 months; P<0.001 for both). Both UCVA and BCVA were better after SBK compared with Trans-PRK at 1 month (-0.07 vs. -0.03; P<0.001) but not at 3 months (-0.08 vs. -0.07; P=0.223). The patients in Trans-PRK group were significantly more hyperopic compared with those in the SBK group at 1 month (0.11 vs. 0.04; P=0.034) and 3 months (0.11 vs. 0.04; P=0.011) postoperatively. Subgroup analysis showed that patients with myopia >3 diopters were more hyperopic at 1 month postoperatively as compared to patients with myopia of ≤3 diopters. CONCLUSIONS Both Trans-PRK and SBK are effective procedures to correct mild to moderate myopia and myopic astigmatism. Patients undergoing SBK experience quick visual recovery. Both procedures had no difference in visual outcomes 3 months postoperatively.
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Shaaban YM, Badran TAF. Tear meniscus evaluation after microkeratome laser in situ keratomileusis, femtosecond laser and femtosmile laser techniques using anterior segment optical coherence tomography. Clin Ophthalmol 2018; 12:1337-1345. [PMID: 30104861 PMCID: PMC6074781 DOI: 10.2147/opth.s169091] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Purpose The purpose of this study was to compare the effects of three different corneal refractive surgeries: microkeratome laser in situ keratomileusis (LASIK), femtosecond laser in situ keratomileusis (FS-LASIK) and femtosecond small incision lenticule extraction (FS-SMILE) on 6-month postoperative stability of tear film to provide a basis for selection of operative procedures. Patients and methods This is a prospective, randomized, comparative study that included 90 eyes of three equal groups of patients. Each group was subjected to a different laser technique: LASIK, FS-LASIK and FS-SMILE. Using anterior segment spectral domain optical coherence tomography (AS-SD-OCT), the lower tear meniscus parameters were measured preoperatively and 1 week, 1 month, 3 months and 6 months postoperatively. Changes were studied and compared. Results There was a statistically significant difference in tear meniscus height (TMH) between FS-SMILE and FS-LASIK in the first week (P = 0.003) and first month (P = 0.002) with no statistically significant difference between both techniques at 3 and 6 months postoperatively. In FS-SMILE, TMH returned to 95% of its preoperative level after 1 month. There was no statistically significant difference in TMH between FS-LASIK and microkeratome LASIK techniques after 1 week and 1 month, but there was a statistically significant difference between both techniques in 3 months (P = 0.019) and 6 months (P = 0.032). Tear meniscus area (TMA) showed no statistically significant difference between FS-SMILE and FS-LASIK at all points of follow-up, but there was a statistically significant difference between both techniques and microkeratome LASIK (all P < 0.05). Microkeratome LASIK parameters failed to reach the preoperative level till 6 months. Conclusion Early recovery of the lower TMH can be achieved as early as 1 month post-operatively with the FS-SMILE technique compared to FS-LASIK and microkeratome LASIK techniques.
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Zheng X, Zhang D, Li S, Zhang J, Zheng J, Du L, Gao J. An Experimental Study of Femto-Laser in Assisting Xenograft Acellular Cornea Matrix Lens Transplantation. Med Sci Monit 2018; 24:5208-5215. [PMID: 30051889 PMCID: PMC6076428 DOI: 10.12659/msm.909294] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Background The aim of this study was to evaluate the feasibility of using a femto-laser in assisting xenograft cornea matrix lens transplantation in correcting ametropia, along with evaluating the effectiveness and predictability of this procedure. Material/Methods A corneal matrix pouch was prepared on the right eyes on 8 healthy New Zealand rabbits by a femto-laser that was also employed to perform small incision lenticule extraction (SMILE) on 8 bovine cornea matrix lenses (+6D). A lens was treated acellular and implanted into a right rabbit cornea matrix pouch. Surface inflammation was observed at 1, 2, 4, 8, 12, and 24 weeks after surgery. Anterior ocular segment optical coherence tomography (OCT), corneal topography, retinoscopy, and cornea endothelial cell enumeration were performed. Results All the surgeries were successfully performed without any complications. The hyperopia condition of the rabbit eyes transformed into myopia status at an early stage and gradually developed hyperopia. Diopter at 24 weeks after surgery was 1/3 of that before surgery. Central corneal thickness stabilized at 4 weeks after surgery. Anterior segment OCT showed a clear lens edge at early post-operative stage, and blurred edge at 24 weeks later, indicating gradual fusion with the rabbit corneal matrix. Conclusions Femto-laser assisted xenograft corneal matrix lens transplantation is safe and effective in correcting ametropia, with satisfactory predictability, thus providing novel choice for correcting ametropia.
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Affiliation(s)
- Xiaoli Zheng
- Department of Ophthalmology, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
| | - Dan Zhang
- Department of Ophthalmology, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
| | - Siyuan Li
- Department of Ophthalmology, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
| | - Jing Zhang
- Department of Ophthalmology, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
| | - Juan Zheng
- Department of Joint Laboratory for Translational Medicine Research, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
| | - Liqun Du
- Department of Ophthalmology, Qilu Hospital of Shandong University, Qilu, Shandong, China (mainland)
| | - Jianlu Gao
- Department of Ophthalmology, Liaocheng City People's Hospital, Liaocheng, Shandong, China (mainland)
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Katsanos A, Arranz-Marquez E, Cañones R, Lauzirika G, Rodríguez-Perez I, Teus MA. Retinal nerve fiber layer thickness after laser-assisted subepithelial keratomileusis and femtosecond LASIK: a prospective observational cohort study. Clin Ophthalmol 2018; 12:1213-1218. [PMID: 30013314 PMCID: PMC6038866 DOI: 10.2147/opth.s168033] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Purpose Based on the assumption that high levels of intraocular pressure (IOP) during femtosecond laser-assisted in situ keratomileusis (FS-LASIK) may compromise the retinal nerve fiber layer (RNFL), newer femtosecond platforms that operate without causing significant IOP elevation have been developed in recent years. However, this assumption has not been adequately tested. The aim of the current study was to evaluate possible changes in RFNL thickness in nonglaucomatous myopic patients undergoing FS-LASIK using the 60 KHz IntraLase® device that significantly elevates the IOP for an appreciable period of time vs an advanced surface ablation technique (laser-assisted subepithelial keratomileusis, LASEK) that does not induce any IOP elevation. Methods This was a prospective, observational, controlled cohort study. One randomly selected eye of 114 consecutive eligible patients was analyzed. Inclusion criteria were myopia up to -6.00 diopters and astigmatism up to -2.00 diopters. As clinically indicated, 50 patients underwent LASEK and 64 underwent FS-LASIK. The RNFL thickness was determined with a spectral-domain optical coherence tomography device preoperatively and 3 months postoperatively by the same masked observer. Results There was no significant difference in preoperative refractive error, age, or sex between the groups. Preoperatively, central corneal thickness was significantly lower in the LASEK group (529.1±36.1 vs 562.4±31.6 µm, P=0.001). For the LASEK group, there was no significant difference between preoperative and postoperative RNFL thickness in the studied sectors (superior-temporal, temporal, inferior-temporal, average). For the FS-LASIK group, compared to preoperative RNFL measures, statistically significant thicker postoperative values were found for the average RNFL (mean difference: 0.67 µm, 0.7% increase, P=0.008) and the inferior-temporal sector (mean difference: 0.92 µm, 0.6% increase, P=0.02). Conclusion LASIK with a femtosecond platform that induces high intraoperative IOP did not cause RNFL thinning. The observed differences between preoperative and postoperative values are below the axial resolution limit of optical coherence tomography devices.
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Affiliation(s)
- Andreas Katsanos
- Clínica Novovisión, Madrid, Spain, .,Department of Ophthalmology, University of Alcala, Alcala de Henares, Spain, .,Department of Ophthalmology, University of Ioannina, Ioannina, Greece,
| | - Esther Arranz-Marquez
- Clínica Novovisión, Madrid, Spain, .,Ophthalmology Clinic, Rey Juan Carlos Universitary Hospital, Móstoles, Madrid, Spain
| | - Rafael Cañones
- Department of Ophthalmology, University of Alcala, Alcala de Henares, Spain,
| | | | | | - Miguel A Teus
- Clínica Novovisión, Madrid, Spain, .,Department of Ophthalmology, University of Alcala, Alcala de Henares, Spain,
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Wang J, Ren Y, Liang K, Jiang Z, Tao L. Changes of corneal high-order aberrations after femtosecond laser-assisted in situ keratomileusis. Medicine (Baltimore) 2018; 97:e0618. [PMID: 29718869 PMCID: PMC6392645 DOI: 10.1097/md.0000000000010618] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Femtosecond laser-assisted in situ keratomileusis (FS-LASIK) has gained widespread popularity as a safe, effective and predictable treatment for correcting myopia and myopic astigmatism.However, complications such as biomechanical changes, structural weakness, dry eye and induction of high-order aberrations (HOAs) have been associated with FS laser excision. The induction of HOAs has been reported to reduce quality of vision, leading to increased glare, halos, starburst and deterioration of contrast function corneal HOAs play a significant role in whole-eye aberration. Thus, it is necessary to investigate the changes of corneal high-order aberrations after FS-LASIK. METHODS One hundred thirty-four eyes from 68 consecutive patients with myopia or myopic astigmatism were enrolled in this study. Corneal topography and visual acuity were measured preoperatively and at 1, 3, 6, and 12 months after FS-LASIK. Wavefront errors from the whole cornea, anterior cornea, and posterior cornea were measured by Pentacam. RESULTS Corneal aberrations on the posterior surface were less affected by FS-LASIK compared with those on the anterior surface and the whole cornea. The high-order aberrations (HOAs) on the whole and anterior corneal surfaces increased significantly at 1 month after surgery (P = .000, P = .000), while HOAs on the posterior surface did not significantly change (P = 1.000). The spherical aberration on the whole corneal and anterior corneal surfaces were significantly increased at 1 and 3 months postoperatively (P = .000 and P = .000, respectively), along with the vertical coma on the whole and anterior corneal surfaces at 1 and 3 months (P = .000 and P = .000, respectively). There was no significant difference in horizontal coma or trefoil on the whole, anterior and posterior corneal surfaces after surgery compared with preoperatively (all P = 1.000). CONCLUSION After FS-LASIK changes in corneal aberration occurred mainly on the anterior surface, which may have a significant effect on visual quality.
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Bao F, Wang J, Cao S, Liao N, Shu B, Zhao Y, Li Y, Zheng X, Huang J, Chen S, Wang Q, Elsheikh A. Development and clinical verification of numerical simulation for laser in situ keratomileusis. J Mech Behav Biomed Mater 2018; 83:126-134. [PMID: 29704827 DOI: 10.1016/j.jmbbm.2018.04.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 04/12/2018] [Accepted: 04/17/2018] [Indexed: 10/17/2022]
Abstract
To develop and validate numerical models of the laser in situ keratomileusis (LASIK) procedure through considering its effect on corneal biomechanical behavior. 3D finite element models of the human eye were developed to simulate LASIK. The models' predictions of post-operative corneal elevation, corneal refractive power with vector decomposition (M-c-pos, J0-c-pos, J45-c-pos) and refractive error correction (M-rec, J0-rec, J45-rec) were compared against clinical data obtained for 28 eyes of 28 patients. A parallel exercise was conducted to estimate the post-operative corneal shape using a shape subtraction method (SSM) - which does not consider the effects of LASIK on corneal mechanical behavior - and the results are compared with the finite element method (FEM). A significant decrease in elevation differences between FEM predictions and clinical data was found compared with the differences between SSM results and clinical data (p = 0.000). In addition, there were no significant differences in post-operative equivalent sperical corneal refractive power between FEM results and corresponding clinical data (M-c-pos: p = 0.501), while SSM showed significant differences with clinical data (M-c-pos: p = 0.000). Further, FEM achieved a predicted value of M-c-pos within ± 1.00D accuracy in 100% of cases, compared with 57% achieved by the SSM. M-rec predicted by FEM was not significantly different from clinical results (p = 0.085), while SSM overestimated it (p = 0.000). The match between LASIK numerical model predictions with clinical measurements improved significantly when the procedure's effect on corneal biomechanical behavior was considered. This outcome has important implications on efforts to develop planning tools for refractive surgery.
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Affiliation(s)
- FangJun Bao
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China; The institution of ocular biomechanics, Wenzhou Medical University, Wenzhou, Zhejiang Province 325027, China
| | - JunJie Wang
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China; The institution of ocular biomechanics, Wenzhou Medical University, Wenzhou, Zhejiang Province 325027, China
| | - Si Cao
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - Na Liao
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - Bao Shu
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - YiPing Zhao
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - YiYu Li
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - XiaoBo Zheng
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China; The institution of ocular biomechanics, Wenzhou Medical University, Wenzhou, Zhejiang Province 325027, China
| | - JinHai Huang
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China
| | - ShiHao Chen
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China.
| | - QinMei Wang
- Eye Hospital, WenZhou Medical University, Wenzhou 325027, China; The institution of ocular biomechanics, Wenzhou Medical University, Wenzhou, Zhejiang Province 325027, China.
| | - Ahmed Elsheikh
- School of Engineering, University of Liverpool, Liverpool L69 3GH, UK; National Institute for Health Research (NIHR) Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, UK
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Xia LK, Ma J, Liu HN, Shi C, Huang Q. Three-year results of small incision lenticule extraction and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis for correction of high myopia and myopic astigmatism. Int J Ophthalmol 2018; 11:470-477. [PMID: 29600182 DOI: 10.18240/ijo.2018.03.18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 11/28/2017] [Indexed: 11/23/2022] Open
Abstract
AIM To compare and calculate the 3-year refractive results, higher-order aberrations (HOAs), contrast sensitivity (CS) and dry eye parameters after small incision lenticule extraction (SMILE) and wavefront-guided femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) for correction of high myopia and myopic astigmatism. METHODS In this prospective, non-randomized comparative study, 78 eyes with spherical equivalent (SE) of -8.11±1.09 diopters (D) received a SMILE surgery, and 65 eyes with SE of -8.05±1.12 D received a wavefront-guided FS-LASIK surgery with the VisuMax femtosecond laser (Carl Zeiss Meditec, Jena, Germany) for flap cutting. Visual acuity, manifest refraction, CS, HOAs, ocular surface disease index (OSDI) and tear break-up time (TBUT) were evaluated during a 3-year follow-up. RESULTS The difference of uncorrected distance visual acuity (UDVA) postoperatively was achieved at 1mo and at 3mo, whereas the difference of the mean UDVA between two groups at 3y were not statistically significant (t=-1.59, P=0.13). The postoperative change of SE was 0.89 D in the FS-LASIK group (t=5.76, P=0.00), and 0.14 D in the SMILE group (t=0.54, P=0.59) from 1mo to 3y after surgery. At 3-year postoperatively, both HOAs and spherical aberrations in the SMILE group were obviously less than those in the FS-LASIK group (P=0.00), but the coma root mean square (RMS) was higher in the SMILE group (0.59±0.26) than in the FS-LASIK group (0.29±0.14, P=0.00). The mesopic CS values between two groups were not statistically significant at 3y postoperatively. Compared with the FS-LASIK group, lower OSDI scores and longer TBUT values were found in the SMILE group at 1mo and 3mo postoperatively. With regard to safety, no eye lost any line of CDVA in both groups at 3y after surgery. CONCLUSION Both SMILE and wavefront-guided FS-LASIK procedures provide good visual outcomes. Both procedures are effective and safe, but SMILE surgery achieve more stable long-term refractive outcome and better control of early postoperative dry eye as compared to FS-LASIK.
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Affiliation(s)
- Li-Kun Xia
- Department of Ophthalmology, Shengjing Hospital, China Medical University, Shenyang 110004, Liaoning Province, China
| | - Jing Ma
- Department of Ophthalmology, the General Hospital of Shenyang Military, Shenyang 110016, Liaoning Province, China
| | - He-Nan Liu
- Department of Ophthalmology, Shengjing Hospital, China Medical University, Shenyang 110004, Liaoning Province, China
| | - Ce Shi
- Department of Ophthalmology, Shengjing Hospital, China Medical University, Shenyang 110004, Liaoning Province, China
| | - Qing Huang
- Department of Ophthalmology, Shengjing Hospital, China Medical University, Shenyang 110004, Liaoning Province, China
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