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Femtosecond Laser-assisted Cataract Surgery in Patients With Prior Glaucoma Surgery. J Glaucoma 2022; 31:547-556. [PMID: 35763680 DOI: 10.1097/ijg.0000000000002034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 03/29/2022] [Indexed: 11/25/2022]
Abstract
PRCIS Femtosecond laser-assisted cataract surgery (FLACS) is a safe procedure in glaucomatous eyes with prior glaucoma surgery, evidenced by stable intraocular pressure (IOP) and medication use, acceptable success rate, disease stability, and low complication rates at 1-year postoperative. PURPOSE The purpose of this study was to assess the 1-year efficacy and safety of FLACS in glaucomatous eyes with prior glaucoma surgery. MATERIALS AND METHODS Retrospective case series of all consecutive glaucomatous eyes with previous glaucoma surgery that underwent FLACS using the Catalys Precision Laser System with or without concomitant glaucoma surgery at a single ophthalmology center, between 2014 and 2020. Efficacy included change in IOP, glaucoma medication use, best-corrected visual acuity, and surgical success at 12 months postoperatively (POM12). Safety included structural and functional measures of disease stability and postoperative adverse events. RESULTS A total of 57 eyes with an average age of 62.6±8.1 years were included. At POM12, IOP decreased from 14.5±6.6 mmHg to 13.5±3.7 mm Hg (P=0.22) and glaucoma medication use decreased from 2.1±1.5 to 1.8±1.4 with a marginal significance (P=0.089). Best-corrected visual acuity improved significantly in both groups (P<0.001) and surgical success ranged between 74% and 90% according to the study's success criteria. Safety was favorable with disease stability evidenced by lack of deterioration in cup-to-disc ratio, visual field mean deviation, retinal nerve fiber layer thickness, and ganglion cell-inner plexiform layer thickness. One eye with prior history of trabeculectomy experienced transient bleb leak. Other adverse events were minor without sight-threatening sequelae. CONCLUSIONS The results of this study suggest that FLACS with or without concomitant glaucoma surgery could be a safe procedure in glaucomatous eyes-a population for which FLACS has been relatively contraindicated. Nonetheless, in those with preexisting filtering bleb, extra attention should be paid to the bleb area.
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Tan Q, Zhu M, Du F, Jiang X, Huang X, Chen J, Peng H, Wang D. Changes in Retinal Vessel Flow after Small Incision Lenticule Extraction. COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2022; 2022:8437066. [PMID: 35309847 PMCID: PMC8926514 DOI: 10.1155/2022/8437066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 01/14/2022] [Accepted: 01/20/2022] [Indexed: 11/18/2022]
Abstract
Objective In order to analyze changes in retinal vessel flow after small incision lenticule extraction (SMILE). Methods A total of 32 patients (62 eyes) who underwent SMILE were enrolled in this prospective study. Optical parameters, including vessel density (VD), and perfusion density (PD) of foveal, parafoveal, and perifoveal regions, respectively, were measured before surgery and at 1 day, 1 week, 1 month, and 3 months postoperation. Preoperative parameters and surgical parameters were recorded. Results Significant decreases in VD and PD on postoperative day 1 were detected in all quadrants, both in 3 mm and in 6 mm regions (P < 0.001). One month after surgery, VD returned to preoperative levels. None of the preoperative and surgical parameters were significantly correlated with the VD and PD fluctuations (all P > 0.05). Conclusion. VD may decrease significantly with regional disparity 1 day after SMILE while recovering at 1 month. Elevation of intraocular pressure due to suction may account for such changes.
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Affiliation(s)
- Qian Tan
- Department of Ophthalmology, Shenzhen People's Hospital, Shenzhen 518000, China
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Minyi Zhu
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Fangfang Du
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Xianming Jiang
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Xiaoshan Huang
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Jingfang Chen
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Hongjun Peng
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
| | - Danyang Wang
- Department of Ophthalmology, The Seventh Affiliated Hospital of Sun Yat-sen University, Shenzhen 518000, China
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Jiang Y, Wang Z, Li Y, Li Y, Lu TC. Retinal Nerve Fibre Layer Thickness Change Following Femtosecond Laser-Assisted in situ Keratomileusis. Front Med (Lausanne) 2021; 8:778666. [PMID: 34912833 PMCID: PMC8666688 DOI: 10.3389/fmed.2021.778666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 10/19/2021] [Indexed: 11/13/2022] Open
Abstract
Purpose: To evaluate the effect of femtosecond laser-assisted in situ keratomileusis (FS-LASIK) on retinal fovea thickness, volume, and retinal nerve fibre layer (RNFL) thickness. Methods: Thirty-seven eyes (37 patients) undergoing FS-LASIK were included in this prospective study. Optical coherence tomography (OCT) was performed 1 day before, 1 h and 1 day after FS-LASIK surgery. Result: Eighteen male and nineteen females were enrolled. Mean patient age was 22.94 ± 4.22 years. One hour postoperatively, macula fovea thicknesses, macula fovea volume, macula parafovea thickness, macula parafovea volume, macula perifovea thickness, macula perifove volume, temporal RNFL thickness, and superior RNFL thickness measures showed significant decrease (t = 6.171, 6.032, and 9.837, 9.700, 2.532, 4.393, 4.926, 2.265; p = 0.000, 0.000, 0.000, 0.000, 0.016, 0.000, 0.000, and 0.011). Day 1 post-operation, macula fovea thicknesses, macula fovea volume, macula parafovea thickness, macula parafovea volume, and inferior RNFL thickness measures showed significant change compared to preoperative measures (t = 3.620, 3.220, 2.901, 2.910, 3.632; p = 0.001, 0.003, 0.006, 0.006, and 0.001). Conclusion: Our data suggest there are alterations in retinal foveal and RNFL measurements by OCT 1 h and 1 day after FS-LASIK surgery.
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Affiliation(s)
- Yang Jiang
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.,Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Zhonghai Wang
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.,Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Ying Li
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences, Beijing, China.,Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Peking Union Medical College, Beijing, China
| | - Yong Li
- Department of Ophthalmology, Xi'an Fourth Hospital, Xi'an, China
| | - Thomas Chengxuan Lu
- School of Medicine, University of New South Wales, Kensington, NSW, Australia
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Ozsaygili C, Altunel O, Duru N. Evaluation of the change in retinal thickness after femtosecond laser-assisted laser in situ keratomileusis and photorefractive keratectomy. Curr Eye Res 2021; 47:18-24. [PMID: 34231433 DOI: 10.1080/02713683.2021.1951297] [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: 10/20/2022]
Abstract
PURPOSE OF THE STUDY To investigate the change in individual retinal layer thickness by spectral-domain optical coherence tomography (SD-OCT) in eyes underwent femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK) and photorefractive keratectomy (PRK). METHODS In patients who underwent PRK and FS-LASIK, changes in the thickness of all retinal layers in the foveal, parafoveal, and perifoveal regions were evaluated by SD-OCT automated segmentation analysis at pre-operatively and different time points post-operatively. RESULTS Seventy-one eyes of 71 patients (38 patients in PRK, 33 patients in LASIK) were included. In the pre-operative period, mean spherical equivalent (SE), mean keratometry, axial length, and segmentation values of the retinal layers were similar (P> .05). In the PRK group, the pre-operative measurements of individual retinal layers did not show a statistically significant difference compared to the post-operative measurements on the 1st day, 1st week, and 1st month. In the FS-LASIK group, the mean inner nuclear layer (INL) thickness one day after the surgery was significantly higher than that before surgery in the foveal (21.22 ± 4.66 µm vs 19.03 ± 4.50 µm, P= .013) and parafoveal regions (41.98 ± 3.70 µm vs 40.56 ± 3.49 µm, P= .044). CONCLUSIONS The findings of our study suggest that the increase of INL thickness may be due to temporary structural and circulatory changes of the retina that may occur in the suction phase in the FS-LASIK procedure.
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Affiliation(s)
- Cemal Ozsaygili
- Kayserı City Training and Research Hospital, Kocasinan, Turkey
| | - Orhan Altunel
- Kayserı City Training and Research Hospital, Kocasinan, Turkey.,Kutahya Evliya Celebi Training and Research Hospital, Kutahya, Turkey
| | - Necati Duru
- Kayserı City Training and Research Hospital, Kocasinan, Turkey
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Reply: Transient effect of suction on retinal neuro-vasculature in myopic patients after small-incision lenticule extraction. J Cataract Refract Surg 2021; 47:683-684. [PMID: 32932367 DOI: 10.1097/j.jcrs.0000000000000078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liu J, Tonk RS, Huang AM, Han E, Karp CL, Zeng M, Zou H, Zheng Y, Luo W, Sha X, Liu Z. Transient effect of suction on the retinal neurovasculature in myopic patients after small-incision lenticule extraction. J Cataract Refract Surg 2021; 46:250-259. [PMID: 32126039 DOI: 10.1016/j.jcrs.2019.09.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To characterize retinal neurovasculature changes after small-incision lenticule extraction (SMILE) in myopic patients. SETTING Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University, China. DESIGN Prospective interventional study. METHODS The corrected distance visual acuity/uncorrected distance visual acuity, corrected intraocular pressure (CIOP), and corneal tomography were evaluated at baseline (PRE), postoperative day (POD) 1, and POD 7. Ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses were measured. The vessel area densities (VADs, %), vessel skeleton densities (VSDs, %), vessel diameter index (VDI), and fractal dimensions (Dbox) of the superficial vascular plexus (SVP) and deep vascular plexus (DVP) were measured in a circular area (ϕ 2.5 mm) centered on the fovea. RESULTS A total of 38 myopic patients were recruited. The GCIPL thickness was increased after SMILE at POD 1 and POD 7 (P < .01) but no significant changes in the pRNFL thickness. The VAD, VSD, and Dbox of the SVP were decreased at POD 1 (P < .01), but not at POD 7. The VDI in small vessels of the SVP and DVP was decreased at POD 1 (P < .05) and increased at POD 7 (P < .05). Changes in CIOP were positively correlated with changes in the GCIPL thickness. Changes in CIOP were negatively correlated with changes in the VAD of small vessels and the Dbox of total vessels in the DVP. Changes in CIOP were negatively correlated with the VSD and VDI of small vessels in the DVP and changes in the VDI of big vessels in the SVP. CONCLUSIONS The transient fluctuations in the retinal neurovasculature after SMILE may represent a characteristic homeostasis pattern in patients after refractive surgery.
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Affiliation(s)
- Jiayan Liu
- Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University (Liu, Zeng, Zou, Zheng, Luo, Sha, Liu), Department of Ophthalmology, the Sixth Affiliated Hospital of Guangzhou Medical University (Liu), Qingyuan, China; and Bascom Palmer Eye Institute, University of Miami Miller School of Medicine (Tonk, Huang, Han, Karp), Miami, Florida, USA
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Effects of SMILE Surgery on Intraocular Pressure, Central Corneal Thickness, Axial Length, Peripapillary Retinal Nerve Fiber Layer, and Macular Ganglion Cell Complex Thickness. J Ophthalmol 2020. [DOI: 10.1155/2020/4934196] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Purpose. To evaluate the change in intraocular pressure (IOP), central corneal thickness (CCT), axial length, peripapillary retinal nerve fiber layer (RNFL) thickness, and macular ganglion cell complex (GCC) thickness after small incision lenticule extraction (SMILE) surgery. Methods. This prospective observational study was conducted in Espace Nouvelle Vision, Ophthalmological Clinic, Paris, France. Fifty eyes of 25 patients were enrolled in this study and underwent SMILE surgeries. IOP, central corneal thickness (CCT), axial length (AL), peripapillary RNFL thickness, and macular GCC thickness were measured before and at 3 months after SMILE. Results. The mean preoperative spherical equivalent was −3.15 ± 1.50 diopters (D), and the mean postoperative value was 0.15 ± 0.28 D. After SMILE surgery, IOP decreased from 15.03 ± 2.79 mmHg to 11.02 ± 2.73 mmHg and 10.02 ± 2.21 mmHg at 1 and 3 months, respectively (
for both comparisons). The mean decrease in measured IOP as a function of ablation depth was 0.065 ± 0.031 mmHg/μm. CCT decreased from 545.98 ± 26.61 μm to 478.40 ± 30.26 μm after SMILE surgery (
). AL decreased from 24.80 ± 0.84 mm to 24.70 ± 0.83 mm (
). There was no statistically significant change in mean peripapillary RNFL or mean GCC thickness after SMILE surgery. Conclusions. SMILE surgery modified IOP measurement, CCT, and AL but did not change peripapillary RNFL and macular GCC thicknesses. The postoperative drop in measured IOP might be explained by the decreased CCT. An accurate re-evaluation of AL should be performed before cataract surgery among post-SMILE patients.
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Chen Y, Liao H, Sun Y, Shen X. Short-term changes in the anterior segment and retina after small incision lenticule extraction. BMC Ophthalmol 2020; 20:397. [PMID: 33028265 PMCID: PMC7539406 DOI: 10.1186/s12886-020-01668-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Accepted: 09/30/2020] [Indexed: 11/30/2022] Open
Abstract
Background To analyse short-term changes in the anterior segment and retina after small incision lenticule extraction (SMILE). Methods Patients with myopia scheduled for SMILE were recruited from Ruijin Hospital, Shanghai, China. Basic patient information such as age, sex, and refractive errors was recorded. Ocular measurements were taken before surgery, and 1 day and 1 week after surgery; they included axial length (AL), central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), white to white (WTW), pupil diameter (PD), macular thickness (MT), ganglion cell layer thickness (GCL), retinal nerve fiber layer thickness (RNFL), choroidal thickness (CT), macular vessel density, and optic disc vessel density. Results Sixty-one eyes of 31 patients were selected for this study. AL, CCT, ACD, and postoperative PD were significantly reduced (p < 0.05), while LT was thickened after surgery (p < 0.05). MT at the fovea decreased 1 day and 1 week after surgery (p < 0.05). GCL showed no significant changes after surgery. RNFL was unchanged 1 day after surgery, but the inferior sector was thickened 1 week after surgery. CT was thicker at the fovea 1 day after surgery and 1.0 mm from the fovea in the nasal sector 1 week after surgery. Macular vessel density was significantly decreased 1 day after surgery and most recovered in 1 week. Optic disc vessel density decreased at the peripapillary part 1 day after surgery and recovered after 1 week. ΔACD and ΔLT showed no significant correlation 1 day after surgery. ΔACD was negatively correlated with ΔLT and sphere 1 week after surgery (r = − 0.847, p < 0.000; r = − 0.398, p = 0.002). ΔLT was positively correlated with the sphere 1 week after surgery (r = 0.256, p = 0.048). Conclusion The anterior segment was the most affected, while the retina also underwent changes with regard to MT, RNFL, CT, macular vessel density, and peripapillary vessel density.
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Affiliation(s)
- Yanwei Chen
- Department of Ophthalmology, Ruijin Hospital Affiliated Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Huaping Liao
- Department of Ophthalmology, Ruijin Hospital Affiliated Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Yue Sun
- Department of Ophthalmology, Ruijin Hospital Affiliated Shanghai Jiao Tong University, School of Medicine, Shanghai, China
| | - Xi Shen
- Department of Ophthalmology, Ruijin Hospital Affiliated Shanghai Jiao Tong University, School of Medicine, Shanghai, China.
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Özülken K, İlhan Ç. Evaluation of Retinal Ganglion Cell Layer Thickness in the Early Period After Femtosecond LASIK Surgery. Turk J Ophthalmol 2020; 50:211-215. [PMID: 32854462 PMCID: PMC7469899 DOI: 10.4274/tjo.galenos.2020.29939] [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: 12/01/2022] Open
Abstract
Objectives: To evaluate the early effects of femtosecond laser-assisted in situ keratomileusis (LASIK) surgery on retinal ganglion cell thickness (GCT), peripapillary retinal nerve fiber thickness (NFT), and central macular thickness (CMT) obtained by spectral domain optical coherence tomography (SD-OCT) in a healthy population. Materials and Methods: This case-control study included data from the right eye of 40 subjects without any disease other than refractive error and who had undergone femtosecond LASIK surgery. The preoperative, postoperative 1-hour, and postoperative 3-week GCT, NFT, and CMT values obtained by SD-OCT were compared. Results: The mean age was 27.54±5.99 years (18-45 years). GCT, NFT, and CMT were 18.43±6.03 μm, 107.90±9.01, and 234.3±21.2 μm preoperatively; 18.05±5.93 μm, 108.08±8.92 μm, and 230.1±22.6 μm at postoperative 1 hour; and 17.86±5.27 μm, 107.98±10.13, and 236.3±25.1 μm at postoperative 3 weeks (p=0.159, 0.85, and 0.254, respectively). Conclusion: There were no changes in GCT, NFT, and CMT values evaluated with SD-OCT in the early period after femtosecond LASIK surgery.
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Affiliation(s)
- Kemal Özülken
- TOBB ETU Medical School, Department of Ophthalmology, Ankara, Turkey
| | - Çağrı İlhan
- Hatay State Hospital, Clinic of Ophthalmology, Hatay, Turkey
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Shpak AA, Korobkova MV, Troshina AA. [Effect of cataract extraction with intraocular lens implantation in patients with myopia on optical coherence tomography measurements]. Vestn Oftalmol 2019; 135:3-9. [PMID: 31573551 DOI: 10.17116/oftalma20191350413] [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] [Indexed: 11/17/2022]
Abstract
INTRODUCTION One important question for patients with both myopia and glaucoma is comparability of optical coherence tomography (OCT) data obtained before and after a significant change in eye refraction following cataract extraction surgery with implantation of intraocular lens (IOL). PURPOSE To assess the impact of correcting moderate and high myopia during cataract phacoemulsification with IOL implantation (Phaco/IOL) on the parameters measured by OCT. MATERIAL AND METHODS OCT was performed in 31 patients (31 eyes) with axial eye length of more than 25.5 mm before and the day after Phaco/IOL. Changes in 17 parameters of the retina, retinal ganglion cells-inner plexiform layer (GCIPL), peripapillary retinal nerve fiber layer (RNFL) and optic nerve head (ONH) were analyzed. RESULTS Axial eye length was 26.94±1.09 mm in average (25.57-29.39 mm). The average refractive effect of the intervention was 8.44±4.16 D (3.75-19.0 Diopters). Signal strength in all OCT protocols was no lower than 5. Changes in the average values of OCT parameters after surgery were insignificant. They exceeded 1% of the pre-operation values only in 7 cases, including all 5 parameters of the ONH, and were significant only in 5 out of 17 parameters. For GCIPL and RNFL thickness, the changes on average did not exceed 0.9 μm, for retinal thickness in the macular area - 2.1 μm. In relative terms, the largest decrease (an average of -0.03 mm2; -2.5%) was in the optic disc area. CONCLUSION In patients with high and moderate myopia, the parameters of the retina, RNFL, GCIPL, and ONH, as measured by OCT, changed insignificantly on the first day after Phaco/IOL (considering the signal strength of Cirrus HD-OCT device was not lower than 5).
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Affiliation(s)
- A A Shpak
- S.N. Fyodorov National Medical Research Center 'MNTK 'Eye Microsurgery', 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
| | - M V Korobkova
- S.N. Fyodorov National Medical Research Center 'MNTK 'Eye Microsurgery', 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
| | - A A Troshina
- S.N. Fyodorov National Medical Research Center 'MNTK 'Eye Microsurgery', 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
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Shpak AA, Kostenev SV, Mushkova IA, Korobkova MV. [Effect of corneal refractive surgery on optical coherence tomography measurements]. Vestn Oftalmol 2019; 134:48-53. [PMID: 30499539 DOI: 10.17116/oftalma201813405148] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The effect of significant changes in corneal power after refractive surgery on the parameters of optical coherence tomography (OCT) has not been sufficiently studied. PURPOSE To study effects of corneal refractive surgery on optical coherence tomography (OCT) measurements in patients with moderate and high myopia. MATERIAL AND METHODS OCT was performed in 62 patients (62 eyes) with myopia over 4 D before and one month after LASIK. The changes in 14 parameters of the thickness of the retina, ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) were analyzed. RESULTS The mean refractive effect was 7.07±2.02 D (4.0 to 11.75 D). Postoperative changes in the parameters analyzed were insignificant, averaging not more than 1.3% of the baseline value with the exception of pRNFL thickness in the temporal quadrant (2.2%). Only six of the 14 parameters were statistically significant - retinal thickness in the central subfield and the inner nasal quadrant, average and minimum thickness of GCIPL, and pRNFL thickness (mean and in the temporal quadrant). Individual changes of the parameters in most patients did not exceed the error of method. CONCLUSION In patients with moderate to high myopia, LASIK operation has only a slight effect on the OCT parameters of the retina and pRNFL. Only in patients with very high myopia, the decrease over 10 D in corneal refractive power creates an optical effect of increasing the average thickness of pRNFL and GCIPL by 2-3 μm. This should be taken into account when examining such patients for glaucoma.
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Affiliation(s)
- A A Shpak
- S. Fyodorov Eye Microsurgery Federal State Institution, 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
| | - S V Kostenev
- S. Fyodorov Eye Microsurgery Federal State Institution, 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
| | - I A Mushkova
- S. Fyodorov Eye Microsurgery Federal State Institution, 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
| | - M V Korobkova
- S. Fyodorov Eye Microsurgery Federal State Institution, 59A Beskudnikovsky Blvd., Moscow, Russian Federation, 127486
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Reñones de Abajo J, Estévez Jorge B, González Martín JM, Carreras Díaz H, Loro Ferrer JF, Antón López A. Effect of femtosecond laser-assisted lens surgery on the optic nerve head and the macula. Int J Ophthalmol 2019; 12:961-966. [PMID: 31236353 DOI: 10.18240/ijo.2019.06.13] [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: 10/02/2018] [Accepted: 03/22/2019] [Indexed: 11/23/2022] Open
Abstract
AIM To evaluate the effect of femtosecond laser-assisted lens surgery (FLALS; cataract surgery or refractive lens exchange) on the structure of the optic nerve head and the macula. METHODS This prospective longitudinal study included healthy eyes undergoing FLALS. Eyes with glaucoma or any other ocular disease that could alter optical coherence tomography results were excluded. Retinal nerve fiber layer (RNFL), Bruch's membrane opening-minimum rim width (BMO-MRW) and macular thickness (MT) were measured preoperatively, 1 and 6mo after surgery using spectral-domain optical coherence tomography (SD-OCT). Changes between preoperative and postoperative values were evaluated. RESULTS A total of 87 eyes of 46 patients were included in this study. Preoperative RNFL, BMO-MRW and MT in microns (µm) were 100.77±10.39, 330.31±49.99 and 276.30±33.39, respectively. Postoperative RNFL, BMO-MRW and MT were 104.74±11.55, 348.32±54.05 and 279.83±22.65 1mo after surgery and 102.93±11.17, 343.11±53.4 and 278.90±22.19 6mo after surgery, respectively; which equals an increase of 3.93%, 5.45% and 1.27%, respectively, 1mo after surgery, and 2.14%, 3.87% and 0.94% 6mo after surgery. The differences between the preoperative and the postoperative RNFL and BMO-MRW values were statistically significant (P<0.001). Regarding MT values, there were not statistically significant differences (P=0.26). CONCLUSION Our study suggests that FLALS does not have a negative impact on the structural status of the optic nerve head in healthy eyes, assessed by SD-OCT. There is a slight increase in the values of RNFL, BMO-MRW and MT 1mo and 6mo after surgery.
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Affiliation(s)
- Josefina Reñones de Abajo
- Eurocanarias Oftalmológica, Las Palmas de Gran Canaria 35004, Spain.,Universidad de Las Palmas de Gran Canaria (ULPGC), Las Palmas de Gran Canaria 35001, Spain
| | | | - Jesús María González Martín
- Department of Research, Hospital Universitario de Gran Canaria Doctor Negrín, Las Palmas de Gran Canaria 35019, Spain
| | | | | | - Alfonso Antón López
- Universidad Internacional de Cataluña (UIC), Barcelona 08195, Spain.,Institut Català de Retina (ICR), Barcelona 08017, Spain.,Parc de salut Mar, Barcelona 08024, Spain
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Fakhrutdinova AF, Siplivy VI, Fedoruk NA, Bolshunov AV, Gamidov AA. [Retinal changes after laser interventions on anterior segment of the eyeball]. Vestn Oftalmol 2019; 135:122-129. [PMID: 31215543 DOI: 10.17116/oftalma2019135021122] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Laser surgery of the cornea, iris, angle of the anterior chamber and other parts of anterior segment of the eye sees wide application in clinical practice. The adverse effects it can cause in the anterior segment are well known and understood. At the same time, changes the treatment method can cause in the posterior segment of the eye - primarily, in macular area of the cornea, which is of great importance, have not been studied sufficiently. Purpose of the review - to consolidate previously published data on changes in the retina after laser intervention on the anterior segment of the eye.
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Affiliation(s)
- A F Fakhrutdinova
- Moscow Municipal Polyclinic #219, 47 Jana Rainisa Blvd., Moscow, Russian Federation, 125373
| | - V I Siplivy
- I.M. Sechenov First Moscow State Medical University, Department of Ophthalmology, 8-2 Trubetskaya St., Moscow, Russian Federation, 119991
| | - N A Fedoruk
- Research Institute of Eye Diseases, 11, A, Rossolimo St., Moscow, Russian Federation, 119021
| | - A V Bolshunov
- Research Institute of Eye Diseases, 11, A, Rossolimo St., Moscow, Russian Federation, 119021
| | - A A Gamidov
- Research Institute of Eye Diseases, 11, A, Rossolimo St., Moscow, Russian Federation, 119021
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Changes in Retinal Vasculature and Thickness after Small Incision Lenticule Extraction with Optical Coherence Tomography Angiography. J Ophthalmol 2019; 2019:3693140. [PMID: 31236290 PMCID: PMC6545814 DOI: 10.1155/2019/3693140] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 04/15/2019] [Accepted: 05/09/2019] [Indexed: 12/26/2022] Open
Abstract
Purpose To evaluate the changes in retinal vessel density and thickness after small incision lenticule extraction (SMILE) with optical coherence tomography angiography (OCTA) in myopic patients. Methods In this prospective study, SMILE surgeries were done in 46 eyes of 24 patients with spherical equivalent (SE) more than −6.0 diopters (D). Retinal vessel density and thickness at the macula and optic nerve were recorded with OCTA before and 1 day, 2 weeks, and 1 month after surgery. Intraocular pressure (IOP), uncorrected distance visual acuity (UDVA), and refraction were taken at the same time. Results The superficial retinal vessel density and deep foveal retinal vessel density 1 day after surgery were less than those before surgery; however, the changes at any timepoints were not statistically significant (p=0.2736 and p=0.1590, respectively). Both the superficial vessel density and deep vessel density at the parafoveal and perifoveal regions decreased significantly 1 day postoperatively (all p < 0.05) and then returned to the preoperative level at 2 weeks and stabilized thereafter. There were no significant changes in any of the 4 vessel densities in the area of peripapillary before and 1 day, 2 weeks, and 1 month after surgery (p=0.3345). No statistically significant differences between preoperative and postoperative retinal thickness were detected for the area of macula and optic nerve (all p > 0.5). Conclusions The vessel density at the parafoveal and perifoveal regions decreased at 1 day after SMILE with no effect on the visual acuity and relieved within 2 weeks. Decreased ocular blood flow in response to the spike in IOP may account for such changes.
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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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Cheng W, Liu L, Yu S, Jing Y, Zuo T, Cui T, Zhang H, Ma J, Wei P, Hao W, Lap-Ki Ng A, Pak-Man Cheng G, Chi-Pang Woo V, Chiu K, Wang Y. Real-Time Intraocular Pressure Measurements in the Vitreous Chamber of Rabbit Eyes During Small Incision Lenticule Extraction (SMILE). Curr Eye Res 2018; 43:1260-1266. [PMID: 29874938 DOI: 10.1080/02713683.2018.1485949] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
PURPOSE To investigate real-time intraocular pressure (IOP) during small incision lenticule extraction (SMILE) in rabbit eyes for myopia correction. METHODS During SMILE, real-time IOP was measured in the vitreous cavity of rabbit eyes with an optic fiber pressure sensor (OFPS). Two groups (n = 6 for each) underwent surgery, one group for a -2.00 diopter (D) refractive spherical correction and the other for a -6.00 D correction. RESULTS During surgery, the IOP increased once the glass contact attached to the cornea (Pre-suction), and peaked 83.94 mmHg (SD ± 23.87 mmHg) for the -2.00 D group and 89.17 mmHg (SD ± 22.66 mmHg) for the -6.00 D group, both average values were less than 110 mmHg when suction was initiated to fix the glass contact onto the cornea (Suction on). It then fell to 74.81 mmHg (SD ± 20.64 mmHg) and 76.94 mmHg (SD ± 27.43 mmHg), respectively, and remained stable during lenticule creation (Cutting). After suction stopped (Suction off), IOP fell steeply. During lenticule separation/extraction, the change in IOP was 32.26 mmHg (SD ± 2.91 mmHg). Notably, the average duration of elevated IOP during the surgery was 166.05 s (no longer than 3 min). CONCLUSIONS The IOP fluctuations in the vitreous cavity using an OFPS in a rabbit model during SMILE showed that real-time IOP significantly was increased during Pre-suction, Suction on, Cutting, Suction off, and lenticule separation/extraction compared to baseline IOP, although, peaked at Suction on. Neither the degree of myopic correction nor central corneal thickness significantly affected these changes in IOP.
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Affiliation(s)
- Wenbo Cheng
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China
| | - Lingjia Liu
- b Medical College of Nankai University , Tianjin , China
| | - Shasha Yu
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China.,c Department of Ophthalmology, LKS Faculty of Medicine , The University of Hong Kong , Hong Kong SAR , China
| | - Yin Jing
- d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China
| | - Tong Zuo
- d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China
| | - Tong Cui
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China
| | - Hui Zhang
- d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China
| | - Jiaonan Ma
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China
| | - Pinghui Wei
- d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China
| | - Weiting Hao
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China
| | - Alex Lap-Ki Ng
- c Department of Ophthalmology, LKS Faculty of Medicine , The University of Hong Kong , Hong Kong SAR , China
| | | | | | - Kin Chiu
- c Department of Ophthalmology, LKS Faculty of Medicine , The University of Hong Kong , Hong Kong SAR , China.,f State Key Laboratory of Brain and Cognitive Sciences , The University of Hong Kong , Hong Kong SAR , China
| | - Yan Wang
- a Clinical College of Ophthalmology , Tianjin Medical University , Tianjin , China.,b Medical College of Nankai University , Tianjin , China.,d Tianjin Eye Hospital & Eye Institute, Tianjin Key Lab of Ophthalmology and Visual Science , Clinical College of Ophthalmology , Tianjin , China
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Zhao PF, Zhou YH, Zhang J, Wei WB. Analysis of Macular and Retinal Nerve Fiber Layer Thickness in Children with Refractory Amblyopia after Femtosecond Laser-assisted Laser In situ Keratomileusis: A Retrospective Study. Chin Med J (Engl) 2018; 130:2234-2240. [PMID: 28875960 PMCID: PMC5598337 DOI: 10.4103/0366-6999.213959] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
Background: Localized macular edema and retinal nerve fiber layer (RNFL) thinning have been reported shortly after laser in situ keratomileusis (LASIK) in adults. However, it is still unclear how LASIK affects the retina of children. This study aimed to investigate the macular retina and RNFL thickness in children with refractive amblyopia who underwent femtosecond laser-assisted LASIK (FS-LASIK). Methods: In this study, we included 56 eyes of 32 patients with refractive amblyopia who underwent FS-LASIK in our hospital from January 2012 to December 2016. Foveal (foveal center retinal, parafoveal retinal, and perifoveal), macular inner retinal (superior and inferior), and peripapillary RNFL thicknesses (superior, inferior, temporal, and nasal) were measured using Fourier-domain optical coherence tomography before surgery and 1 day, 3 days, and 1 week after surgery. We divided these patients into three groups based on their refractive error: High myopic group with 22 eyes (equivalent sphere, >6.00 D), mild myopic group with 19 eyes (equivalent sphere, 0–6.00 D), and hyperopic group with 15 eyes (equivalent sphere, >+0.50 D). We compared the macular retina and RNFL thickness before and after LASIK. A paired simple t-test was used for data analysis. Results: One week after surgery, the visual acuity for all 56 eyes of the 32 patients reached their preoperative best-corrected vision. Visual acuity improved two lines or better for 31% of the patients. The residual refractive errors in 89% of the patients were within ±0.5 D. In the high myopic group, the foveal center retinal and parafoveal retinal thicknesses were thicker 1 day and 3 days after surgery than before surgery (t = 2.689, P = 0.012; t = 2.383, P = 0.018, respectively); no significant difference was found 1 week after surgery (P > 0.05). The foveal center retinal and parafoveal retinal thicknesses were greater 1 day after surgery than they were before surgery (P = 0.000 and P = 0.005, respectively) in the mild myopic and hyperopic groups. No significant difference was found 3 days or 1 week after surgery (P > 0.05). In all three groups, no significant difference was found in the macular inner retinal or peripapillary RNFL thickness 1 day, 3 days, or 1 week after surgery (P > 0.05). Conclusions: The foveal center retinal edema after FS-LASIK is mild and reversible in children, that mostly occurred in the high myopic group with no effect on the visual acuity, and is always relieved within 1 week.
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Affiliation(s)
- Peng-Fei Zhao
- Beijing Tongren Eye Center, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Yue-Hua Zhou
- Beijing Tongren Eye Center, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Jing Zhang
- Beijing Tongren Eye Center, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
| | - Wen-Bin Wei
- Beijing Tongren Eye Center, Beijing Ophthalmology and Visual Sciences Key Laboratory, Beijing Tongren Hospital, Capital Medical University, Beijing 100730, China
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The Effect of LASIK Procedure on Peripapillary Retinal Nerve Fiber Layer and Macular Ganglion Cell-Inner Plexiform Layer Thickness in Myopic Eyes. BIOMED RESEARCH INTERNATIONAL 2017; 2017:8923819. [PMID: 29018820 PMCID: PMC5605783 DOI: 10.1155/2017/8923819] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 05/22/2017] [Accepted: 07/24/2017] [Indexed: 11/28/2022]
Abstract
Purpose To evaluate the effect of applied suction during microkeratome-assisted laser in situ keratomileusis (LASIK) procedure on peripapillary retinal nerve fiber layer (RNFL) thickness as well as macular ganglion cell-inner plexiform layer (GC-IPL) thickness. Methods 89 patients (124 eyes) with established myopia range from −3.0 to −8.0 diopters and no associated ocular diseases were included in this study. RNFL and GC-IPL thickness measurements were performed by spectral domain optical coherence tomography (SD OCT) one day before LASIK and at 1 and 6 months postoperatively. Results Mean RNFL thickness prior to LASIK was 93.86 ± 12.17 μm while the first month and the sixth month postoperatively were 94.01 ± 12.04 μm and 94.46 ± 12.27 μm, respectively. Comparing results, there is no significant difference between baseline, one month, and six months postoperatively for mean RNFL (p > 0.05). Mean GC-IPL thickness was 81.70 ± 7.47 μm preoperatively with no significant difference during the follow-up period (82.03 ± 7.69 μm versus 81.84 ± 7.64 μm; p > 0.05). Conclusion RNFL and GC-IPL complex thickness remained unaffected following LASIK intervention.
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Abstract
PURPOSE OF REVIEW Given the popularity of keratorefractive surgery, and an aging populous of patients who have undergone these procedures, there is an increasing need for updated management protocols. This is particularly relevant for patients with chronic progressive diseases such as glaucoma, due to the variety of related diagnostic and management challenges inherent to these diseases. Here, we will review the current literature to provide an update on the management of patients with glaucoma who are undergoing, or have had laser ablative refractive surgery. Preoperative testing and eligibility considerations, intraoperative factors, and postoperative observation and follow-up will be discussed. RECENT FINDINGS Intraoperative intraocular pressure (IOP) rise during flap creation is associated with low risk of acute complications, and furthermore do not appear to have significant long term effects. Modern technologies have improved our ability to determine accurate IOP after refractive surgery despite postoperative changes in corneal architecture. Furthermore, advances in structural imaging allow for earlier detection of even subtle glaucomatous nerve damage. SUMMARY Although glaucoma remains a relative contraindication to refractive surgery, it is a safe procedure for many patients with appropriate perioperative management and follow-up. Advancements in diagnostic modalities have allowed for earlier detection of glaucomatous disease, and subsequent earlier intervention when appropriate. Standardized diagnostic algorithms and rigorous perioperative assessment are critical to safe management of glaucoma patients undergoing refractive corneal surgery.
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Gao SS, Jia Y, Liu L, Zhang M, Takusagawa HL, Morrison JC, Huang D. Compensation for Reflectance Variation in Vessel Density Quantification by Optical Coherence Tomography Angiography. Invest Ophthalmol Vis Sci 2017; 57:4485-92. [PMID: 27571015 PMCID: PMC5015963 DOI: 10.1167/iovs.16-20080] [Citation(s) in RCA: 67] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023] Open
Abstract
PURPOSE To compensate for reflectance variation when quantifying vessel density by optical coherence tomography angiography (OCTA). METHODS Healthy participants received 6×6-mm macular and 4.5×4.5-mm optic nerve head (ONH) angiography scans on a 70-kHz spectral-domain optical coherence tomography system. The split-spectrum amplitude-decorrelation angiography (SSADA) algorithm was used to compute the OCTA signal. Mean reflectance projection and maximum decorrelation projection were used to create en face OCT and OCTA images. Background OCTA noise in static tissue was evaluated in the foveal avascular zone (FAZ). Vessel density was calculated from en face retinal OCTA that was binarized according to a decorrelation threshold. RESULTS The average retinal decorrelation noise in the FAZ was linearly related to the average logarithmic-scale OCT reflectance signal. Based on this relationship, a reflectance-adjusted decorrelation threshold equation was developed to filter out 97.5% of background OCTA noise. A fixed threshold was also used for comparison. The superficial vascular complex vessel density in the macula and ONH were significantly correlated with reflectance signal strength index (SSI) using the fixed threshold. This correlation was removed by using the reflectance-adjusted threshold. Reflectance compensation reduced population variation in 25 healthy eyes from 8.5% to 4.8% (coefficient of variation) in the macula and from 6.7% to 5.4% in the peripapillary region. Within-visit repeatability also improved from 4.4% to 1.8% in the macula and from 3% to 1.7% in the peripapillary region. CONCLUSIONS Compensating for reflectance variation resulted in more reliable vessel density quantification in OCTA.
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