1
|
Ulutas HG, Ozkaya G, Amuk Hamidi N. Comparison of central corneal thickness measured by ultrasound pachymetry, corneal topography, spectral domain- optical coherence tomography, and non-contact specular microscopy. Photodiagnosis Photodyn Ther 2023; 42:103527. [PMID: 36966866 DOI: 10.1016/j.pdpdt.2023.103527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2022] [Revised: 03/20/2023] [Accepted: 03/21/2023] [Indexed: 04/16/2023]
Abstract
BACKGROUND This study aims to investigate the compatibility of central corneal thickness (CCT) measurements obtained with spectral-domain optical coherence tomography (SD-OCT), Scheimpflug-Placido-based corneal topography (CT), non-contact specular microscopy (NCSM), and ultrasonic pachymetry (UP). These four corneal measurement techniques have not been compared in a single study on these many subjects. METHODS CCT was measured in 185 eyes of 185 volunteers with each of the four devices by a single observer. CCTs from Optovue® iVue SD-OCT, Sirius corneal topography, NonconRobo NCSM, and Accutom UP devices were recorded. Compatibility between devices was evaluated with intraclass correlation coefficient (ICC) and Bland-Altman plots. Pairwise comparisons were performed using the Bonferroni test. Measurement differences between devices were analyzed with the Pearson correlation coefficient. RESULTS Of the 185 volunteers, 103 were men, and 82 were women. Their mean age was 48.55 ± 16.6 (18-70) years. Mean CCT values measured by UP, CT, OCT, and NCSM were 546.77 ± 39.2, 535.29 ± 39.2, 526.49 ± 39.05, 505.15 ± 46.1 µm, respectively. Statistically significant differences were found between the mean CCT values obtained from the paired devices (p <0.001). The highest difference between pairs was found between UP and NCSM (43.63 ± 1.8 µm; CI 38.74 to 48.5 µm; p <0.001), while the lowest difference was found between OCT and CT (7.3 ± 1.5 µm; 95%CI 3.1 to 11.6 µm; p <0.001). In pairwise comparisons of four devices, the highest ICC value was between UP and CT (ICC: 0.899, 95%CI 0.759-0.947; p <0.001). CONCLUSION Despite the high correlation between measurements obtained from different methods, notable differences in CCT values exist, rendering devices non-interchangeable. Therefore, alternative brands of the same device may yield different outcomes.
Collapse
Affiliation(s)
- Hafize Gokben Ulutas
- Department of Ophthalmology, University of Health Sciences, Yuksek Ihtisas Training and Research Hospital, Bursa, Türkiye.
| | - Guven Ozkaya
- Department of Biostatistics, Bursa Uludag University, Faculty of Medicine, Bursa, Türkiye
| | - Nagihan Amuk Hamidi
- Department of Ophthalmology, University of Health Sciences, Yuksek Ihtisas Training and Research Hospital, Bursa, Türkiye
| |
Collapse
|
2
|
Soulantzou K, Plakitsi A, Chalkiadaki E, Anastasopoulou M, Karmiris E. Comparison of central corneal thickness in healthy eyes using ultrasound pachymetry, non-contact specular microscopy and a high-resolution Scheimpflug camera. Int Ophthalmol 2023; 43:363-370. [PMID: 35864284 DOI: 10.1007/s10792-022-02431-1] [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: 10/06/2021] [Accepted: 07/05/2022] [Indexed: 11/27/2022]
Abstract
PURPOSE To compare and analyze the interchangeability in measuring central corneal thickness (CCT) using ultrasonic pachymetry (USP, PACHMATE 2, DGH, Inc, Exton, PA, USA), non-contact specular microscopy (NCSM, CEM-530, Nidek CO, LTD, Gamagori, Japan) and a high-resolution Scheimpflug Camera (Pentacam HR, OCULUS, Wetzlar, Germany). METHODS An observational, cross-sectional study was performed recruiting 216 volunteers, for a sample size of 216 eyes with no ocular abnormalities other than refractive errors. All subjects underwent pachymetric measurements obtained by USP, NCSM and Pentacam HR. Examinations were performed by the same examiner with USP always following the noncontact examinations. RESULTS The mean CCT (± SD) was 560.30 ± 38.80 μm, 556.76 ± 36.83 μm and 547.31 ± 35.28 μm for USP, NCSM and Pentacam HR, respectively. The Bland-Altman analysis showed that the highest concordance was found between USP and NCSM, with differences between - 13.18 μm and 20.26 μm. For the differences between measurements obtained with Pentacam HR and USP, the differences at Bland-Altman plot were between - 28.25 and 13.57 μm. The lowest concordance was found for the CCT values measured with Pentacam HR and NCSM, with differences between - 25.67 and 6.86 μm. The intraclass correlation coefficient (ICC) between all pairs of measurements was between 0.979 and 0.987, suggesting that the mean measurements were strongly correlated. CONCLUSION Measurements obtained with all three devices had high correlation. USP and NCSM were found in good agreement and high concordance, too. The above results indicate that these two devices are interchangeable in clinical practice. Pentacam HR may be a useful alternative for measuring CCT; however, it significantly underestimates CCT and cannot be used interchangeably with the other devices that we studied.
Collapse
Affiliation(s)
- Konstantina Soulantzou
- Department of Biomedical Sciences, Division of Optics and Optometry, University of West Attica, Athens, Greece
| | - Athina Plakitsi
- Department of Biomedical Sciences, Division of Optics and Optometry, University of West Attica, Athens, Greece
| | - Evangelia Chalkiadaki
- Department of Ophthalmology, 251 Hellenic Airforce General Hospital, Athens, Greece.
| | - Maria Anastasopoulou
- Department of Statistics and Insurance Science, Graduate of the Economic University of Piraeus, Athens, Greece
| | - Efthymios Karmiris
- Department of Ophthalmology, 251 Hellenic Airforce General Hospital, Athens, Greece
| |
Collapse
|
3
|
Toptan M, Simsek A. A comparison of central corneal thickness measured using noncontact methods and ultrasonic pachymetry. Niger J Clin Pract 2021; 24:1506-1510. [PMID: 34657017 DOI: 10.4103/njcp.njcp_580_20] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Aim The aim of this study is to compare central corneal thickness (CCT) measurements in healthy eyes using ultrasonic pachymetry (UP) with values obtained using anterior segment spectral domain optical coherence tomography (SD-OCT), the Scheimpflug camera system, and noncontact specular microscopy. Material and Methods One hundred and twenty-five eyes of 117 healthy individuals (56 women, 61 men) were included. All patients underwent consecutive CCT measurement with UP, the Scheimpflug camera, anterior segment SD-OCT, and specular microscopy. The four devices could be read. Measurements from the four devices were classified in pairs and compared using the paired t-test. Relations between the devices were analyzed using the Pearson test. An alpha error level of P < 0.05 was regarded as statistically significant. Results The mean age of the healthy individuals included in the study was 34.75 ± 14.55 years (20-76). Mean CCT values were 541.21 ± 29.24 μm with UP, 539.26 ± 29.27 μm with the Scheimpflug camera system, 532.21 ± 29.53 μm with SD-OCT, and 534.45 ± 29.20 μm with specular microscopy. The differences in measurements at the paired t-test were statistically significant (P < 0.001 for all). However, measurements using the four devices exhibited significant mutual correlation (P < 0.001 for all). Conclusions CCT can be measured using different devices. Noncontact methods have now begun replacing UP, regarded as the gold standard. Although CCT values obtained from different devices were correlated, the difference between these measurements was statistically significant. Therefore, the same device should be used for measurement in the diagnosis and follow-up of diseases such as corneal ectasia and glaucoma where corneal thickness is important.
Collapse
Affiliation(s)
- M Toptan
- Department of Ophthalmology, Harran University, School, of Medicine, Şanlıurfa, Turkey
| | - A Simsek
- Department of Ophthalmology, Harran University, School, of Medicine, Şanlıurfa, Turkey
| |
Collapse
|
4
|
Kumar KK, Prakash AA, Neeraja TG, Adappa KT, Prabha TSC, Gangasagara SB. To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOLMaster 700, Cirrus anterior segment optical coherence tomography and Tomey specular microscopy in normal healthy eyes. Indian J Ophthalmol 2021; 69:1713-1717. [PMID: 34146013 PMCID: PMC8374795 DOI: 10.4103/ijo.ijo_3364_20] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Purpose: To compare central corneal thickness measurements obtained by Pentacam with those obtained by IOL Master 700, Cirrus Anterior segment optical coherence tomography and Tomey Specular microscopy in normal healthy eyes. Methods: Two hundred and six eyes of healthy subjects were included in the study. Each subject was assessed by four different methods of measuring central corneal thickness using Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy by a single examiner. Results: The mean CCT [± standard deviation (SD)] for Pentacam, IOL Master 700, Cirrus AS-OCT and Tomey Specular microscopy were Pentacam (Oculus), AS-OCT (Cirrus), IOL Master 700 and Specular microscopy (Tomey) were 523.75 (±27.75), 525.29 (±28.81),517.13 (±28.43) and 512.82 (±27.60) μm, respectively. All the means were significantly different from one another (P < 0.000). The differences between pairs of mean central corneal thickness (CCT) for Pentacam and IOL Master, Pentacam and anterior segment- optical coherence tomography (AS-OCT), and Pentacam and Specular microscopy are statistically significant. Bland–Altman plots showed that pentacam and IOL Master 700 have the closest agreement, followed by AS-OCT. Specular microscopy was found to have the poorest agreement with Pentacam. Conclusion: We found that CCT measurements of Pentacam did not correlate with measurements of IOL Master, or AS-OCT or Specular microscopy. In clinical practice, the devices analyzed should not be used interchangeably due to low agreement regarding CCT values.
Collapse
Affiliation(s)
- K Kiran Kumar
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| | - Akshata A Prakash
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| | - T G Neeraja
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| | - Karishma T Adappa
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| | - T S Chandra Prabha
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| | - Suresh Babu Gangasagara
- Regional Institute of Ophthalmology, Minto Ophthalmic Hospital, BMCRI, Bengaluru, Karnataka, India
| |
Collapse
|
5
|
Oliveira CM, Ribeiro C, Franco S. Corneal imaging with slit‐scanning and Scheimpflug imaging techniques. Clin Exp Optom 2021; 94:33-42. [DOI: 10.1111/j.1444-0938.2010.00509.x] [Citation(s) in RCA: 65] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
| | - Celina Ribeiro
- Centre/Department of Physics, University of Minho, Portugal
E‐mail:
| | - Sandra Franco
- Centre/Department of Physics, University of Minho, Portugal
E‐mail:
| |
Collapse
|
6
|
Gellrich MM, Hufendiek K. [Pachymetry with a video slit lamp]. Ophthalmologe 2021; 118:162-168. [PMID: 32415325 DOI: 10.1007/s00347-020-01108-3] [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: 11/30/2022]
Abstract
BACKGROUND AND OBJECTIVE Presentation and application of a method for pachymetry with the slit lamp based on the concept of a defined optical section. METHODS AND PATIENTS The visible width of an optical section on slit lamp examination with a 45° angle between the slit beam and the central corneal surface was determined in 103 eyes (68 with glaucoma and 35 in patients with keratoconus). The measurements were compared to the pachymetric values previously determined elsewhere for these eyes in order to establish a proportionality factor for calculation of corneal thickness from slit lamp measurements. RESULTS From a linear regression between the external pachymetry and visible width of the optical section in the split lamp, 1.71 was determined to be the factor of proportionality. Applying this factor to single measurements, 82 out of 103 eyes had a maximum difference of 40 µm compared to the external pachymetric values. CONCLUSION Based on a defined optical section at the slit lamp, clinically relevant estimates can be made for central corneal thickness in diseases, such as glaucoma or keratoconus. The difference to the externally measured pachymetric values was within the range of diurnal changes in corneal thickness for 80% of the eyes. Similar to other pachymetric procedures, the reliability of determination of the corneal thickness with the slit lamp also increases when applied intraindividually or for the same eye in the course of time.
Collapse
Affiliation(s)
| | - Karsten Hufendiek
- Universitätsklinik für Augenheilkunde der Medizinischen Hochschule Hannover, Hannover, Deutschland
| |
Collapse
|
7
|
Mayali H, Altinisik M, Diri I, Ilker S, Kurt E, Kayikcioglu O. Comparison of Central Corneal Thickness Measurements by Contact and Non-contact Pachymetry Devices. J Curr Glaucoma Pract 2021; 15:28-31. [PMID: 34393453 PMCID: PMC8322600 DOI: 10.5005/jp-journals-10078-1295] [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: 11/23/2022] Open
Abstract
AIM AND OBJECTIVE To compare central corneal thickness (CCT) measurements obtained by handheld contact ultrasound pachymetry (HCUP) and non-contact pachymetry devices. MATERIALS AND METHODS Ninety eyes of 90 patients (52 male and 38 female) were included in the study. Measurements from two non-contact devices, -specular microscopy (SM, Konan Medical, CA, USA) and Oculus Pentacam (Oculus Inc., Germany)-were compared against HCUP (Pachmate 2, DGH Technology, Inc, PA, USA). Ultrasound measurements were obtained 3 times by the same user and averaged. The differences were calculated by one-way ANOVA. Agreement between measurements were assessed by Bland-Altman plots and intraclass correlation coefficient tests. Coefficient of repeatability (%, CR) was defined as 1.96*standard deviations of the differences between pairs of measurements divided by the average of the means. RESULTS The mean age was 34.31 ± 14.39 (14-74) years, and the mean intraocular pressure was 16.48 ± 2.63 mm Hg (12-21). Mean CCT measured by HCUP, SM, and Pentacam was 557.76 ± 36.76 μm, 550.29 ± 43.74 μm, and 541.41 ± 35.7 μm, respectively (p < 0.05). In the Bland-Altman plot, 95% limit of agreements were 19.5 and 14.18 μm among HCUP measurements, 34.55 μm between HCUP and Pentacam, 41.49 μm between SM and Pentacam, and 46.98 μm between HCUP and SM. CR values (%) were 3.49, 2.54, 6.28, 7.68, and 8.47, respectively. CONCLUSION There were significant differences between the mean CCT values of the measurement devices. CLINICAL SIGNIFICANCE Contact and non-contact devices may not interchangeable in the clinical assessment of CCT. HOW TO CITE THIS ARTICLE Mayali H, Altinisik M, Diri I, et al. Comparison of Central Corneal Thickness Measurements by Contact and Non-contact Pachymetry Devices. J Curr Glaucoma Pract 2021;15(1):28-31.
Collapse
Affiliation(s)
- Huseyin Mayali
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| | | | - Ismail Diri
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| | - Sami Ilker
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| | - Emin Kurt
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| | - Ozcan Kayikcioglu
- Ophthalmology Department, Manisa Celal Bayar University, Manisa, Turkey
| |
Collapse
|
8
|
De Bernardo M, Cornetta P, Marotta G, Salerno G, De Pascale I, Rosa N. Measurement of corneal thickness using Pentacam HR versus Nidek CEM-530 specular microscopy. J Int Med Res 2019; 48:300060519892385. [PMID: 31878803 PMCID: PMC7783267 DOI: 10.1177/0300060519892385] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Objective To compare corneal thickness (CT) measurements using the CEM-530 (Nidal,
Gamagori, Japan) and Pentacam HR (Oculus, Wetzlar, Germany). Methods The CT of 209 healthy subjects (209 right eyes) aged 24 to 89 years
(71.35 ± 10.72 years) was measured at the corneal apex (CA), pupil center
(PC), and thinnest point (TP) with the Pentacam HR and at the corneal center
with the CEM-530 in random order at the same time of day. Results A good correlation but statistically significant difference was found between
the CEM-530 and Pentacam HR measurements at the CA (6.10 ± 8.12 µm,
R2 = 0.8947), PC (7.46 ± 8.57 µm, R2 = 0.8826),
and TP (12.44 ± 10.04 µm, R2 = 0.8392). Comparison of the two
devices produced the following regression formulas: y = 0.8859x + 57.644 for
the CA, y = 0.8852x +56.657 for the PC, and y = 0.8557x + 68.148 for the TP,
where x is the CT obtained with the CEM-530 and y is that obtained with the
Pentacam HR. Conclusions These findings indicate that the CEM-530 produces a thicker corneal
measurement than the Pentacam HR. The herein-proposed correcting factors are
needed to reliably compare these devices.
Collapse
Affiliation(s)
- Maddalena De Bernardo
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Palmiro Cornetta
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Giuseppe Marotta
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Giulio Salerno
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Ilaria De Pascale
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| | - Nicola Rosa
- Department of Medicine, Surgery, and Dentistry, Scuola Medica Salernitana, University of Salerno, Baronissi, Salerno, Italy
| |
Collapse
|
9
|
Fayed MA, Chen TC. Pediatric intraocular pressure measurements: Tonometers, central corneal thickness, and anesthesia. Surv Ophthalmol 2019; 64:810-825. [DOI: 10.1016/j.survophthal.2019.05.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2018] [Revised: 05/15/2019] [Accepted: 05/20/2019] [Indexed: 11/17/2022]
|
10
|
Mayali H, Altinisik M, Sencan S, Pirildar T, Kurt E. A multimodal ophthalmic analysis in patients with systemic sclerosis using ocular response analyzer, corneal topography and specular microscopy. Int Ophthalmol 2019; 40:287-296. [PMID: 31564047 DOI: 10.1007/s10792-019-01173-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2019] [Accepted: 09/19/2019] [Indexed: 11/30/2022]
Abstract
PURPOSE To conduct a multimodal ophthalmic evaluation of systemic sclerosis (SSc) in patients using ocular response analyzer (ORA), Pentacam, and specular microscopy (SM). METHODS Thirty-one SSc patients and a group of age- and sex-matched controls were enrolled in this cross-sectional study. Corneal hysteresis (CH), corneal resistance factor (CRF), corneal-compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with ORA. Anterior chamber depth (ACD), central corneal thickness (CCT), and corneal volume (CV) measurements were obtained using Pentacam. Corneal endothelial cell density (ECD) and CCT were evaluated by SM. RESULTS SSc patients had significantly lower CH, ACD, and ECD values compared to the control group (p = 0.018; < 0.001; < 0.001, respectively). There was no significant difference regarding CRF, IOP, CV, or CCT measurements acquired by Pentacam and SM. Regarding CCT, SM and Pentacam showed relatively better agreement in SSc patients. CONCLUSIONS Multimodal imaging can provide more comprehensive and useful information regarding the ocular involvement of systemic diseases. The multimodal evaluation in our study demonstrated that the pathologic effects of SSc may manifest as reductions in ACD, corneal elasticity, and ECD before there are any detectable changes in corneal thickness or IOP.
Collapse
Affiliation(s)
- Huseyin Mayali
- Ophthalmology Department, Medical School, Manisa Celal Bayar University, Manisa, Turkey
| | - Muhammed Altinisik
- Ophthalmology Department, Medical School, Manisa Celal Bayar University, Manisa, Turkey.
| | - Secil Sencan
- Ophthalmology Department, Tinaztepe Hospital, Izmir, Turkey
| | - Timur Pirildar
- Ophthalmology Department, Medical School, Manisa Celal Bayar University, Manisa, Turkey
| | - Emin Kurt
- Ophthalmology Department, Medical School, Manisa Celal Bayar University, Manisa, Turkey
| |
Collapse
|
11
|
Ohn K, Lee MY, Lee YC, Shin HY. Comparison of Central Corneal Thickness Measurements between Noncontact Specular Microscopy and Ultrasound Pachymetry. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2019. [DOI: 10.3341/jkos.2019.60.7.635] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Kyoung Ohn
- Department of Ophthalmology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea
| | - Mee Yon Lee
- Department of Ophthalmology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea
| | - Young Chun Lee
- Department of Ophthalmology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea
| | - Hye Young Shin
- Department of Ophthalmology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu, Korea
| |
Collapse
|
12
|
Özkan Aksoy N, Çakır B, Doğan E, Alagöz G. Evaluation of Anterior Segment Parameters in Pseudoexfoliative Glaucoma, Primary Angle-Closure Glaucoma, and Healthy Eyes. Turk J Ophthalmol 2018; 48:227-231. [PMID: 30405943 PMCID: PMC6216528 DOI: 10.4274/tjo.03271] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2018] [Accepted: 03/30/2018] [Indexed: 12/01/2022] Open
Abstract
Objectives: To evaluate anterior segment parameters measured by dual Scheimpflug corneal topography in pseudoexfoliative glaucoma (PEXG), primary angle-closure glaucoma (PACG), and healthy eyes. Materials and Methods: One hundred forty-three eyes of 86 patients were included in this study. Forty-seven eyes of 38 patients with PEXG, 30 eyes of 15 patients with PACG, and 66 eyes of 33 healthy subjects were evaluated. Patients who underwent previous ophthalmic surgery and contact lens wearers were excluded. After full ophthalmological examination, mean central corneal thickness (CCT), white-to-white horizontal corneal diameter (WTW), pupillary diameter (PD), anterior chamber volume (ACV), anterior chamber depth (ACD), and mean anterior chamber angle were measured by dual Scheimpflug corneal topography and compared between the three groups. Statistical analyses were done using Statistical Package for Social Sciences for Windows 18.0 program. Results: No statistical difference was found in mean age or gender among the study groups (p>0.05). There were also no statistical differences in CCT, WTW, or PD among the groups (p=0.568, p=0.064, p=0.321, respectively). ACV, ACD, and mean anterior chamber angle values were significantly lower in the PACG group compared to the other groups (p=0.000 for all). There was no statistically significant difference in these measurements between the PEXG and normal eyes. Conclusion: ACV and depth and mean anterior chamber angle were statistically different (lower) in PACG when compared with PEXG and healthy eyes. Dual Scheimpflug corneal topography can be used as an objective method for the measurement of anterior segment parameters in glaucoma.
Collapse
Affiliation(s)
- Nilgün Özkan Aksoy
- Sakarya University Training and Research Hospital, Department of Ophthalmology, Sakarya, Turkey
| | - Burçin Çakır
- Sakarya University Training and Research Hospital, Department of Ophthalmology, Sakarya, Turkey
| | - Emine Doğan
- Sakarya University Training and Research Hospital, Department of Ophthalmology, Sakarya, Turkey
| | - Gürsoy Alagöz
- Sakarya University Training and Research Hospital, Department of Ophthalmology, Sakarya, Turkey
| |
Collapse
|
13
|
Marelli A, De Vita IR, Cozza F, Tavazzi S. Criticality of the measurement of corneal thickness in specular reflection by digital biomicroscope. Cont Lens Anterior Eye 2018; 41:531-537. [PMID: 30197039 DOI: 10.1016/j.clae.2018.08.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2018] [Revised: 08/29/2018] [Accepted: 08/30/2018] [Indexed: 12/01/2022]
Abstract
PURPOSE The aim was to evaluate the effects on corneal thickness (t) measurement, of asymmetry of the CCD position for a digital biomicroscope in specular reflection. METHODS t was deduced from the distance between reflexes from anterior and posterior corneal surfaces using a biomicroscope (Takagi SM70 N), with the illuminator either, (a) farther from sensor side (150 eyes) or, (b) closer to it (134 eyes). The distance between reflexes was also measured on a glass slide and a reference lens, with nominal thicknesses of 1580 and 520 μm, respectively. Corneal thickness (tPACH) was also measured by pachymeter (Canon TX-20 P). RESULTS When biomicroscope asymmetry was ignored, t for the glass slide was (a) 1760 and (b) 1404 μm. Correcting for the asymmetry provided corresponding values of 1588 and 1591 μm. For the lens, t was (a) 696 and (b) 543 μm, or 642 and 497 μm, when using the approximation of parallel surfaces (APS). Correcting for the asymmetry gave 565 and 552 μm (578 and 564 μm, with APS). Mean corneal t was (a) 560 and (b) 467 μm, (564 and 468 μm, with APS). Correcting for asymmetry gave (a) 506 and (b) 529 μm (508 and 530 μm, with APS). Mean tPACH was 552 μm. CONCLUSION Biomicroscope asymmetry critically affects corneal thickness measurement in specular reflection. Induced errors can be accounted for and corrected, however. While the correction to the curvature radius is clinically relevant, it plays a minor role compared to asymmetry.
Collapse
Affiliation(s)
- Arianna Marelli
- University of Milano Bicocca, Department of Materials Science, via R. Cozzi 55, I-20125 Milan, Italy
| | - Ivan Roberto De Vita
- University of Milano Bicocca, Department of Materials Science, via R. Cozzi 55, I-20125 Milan, Italy
| | - Federica Cozza
- University of Milano Bicocca, Department of Materials Science, via R. Cozzi 55, I-20125 Milan, Italy; University of Milano Bicocca, COMiB Research Centre in Optics and Optometry, via R. Cozzi 55, I-20125 Milan, Italy
| | - Silvia Tavazzi
- University of Milano Bicocca, Department of Materials Science, via R. Cozzi 55, I-20125 Milan, Italy; University of Milano Bicocca, COMiB Research Centre in Optics and Optometry, via R. Cozzi 55, I-20125 Milan, Italy.
| |
Collapse
|
14
|
Precision of a new ocular biometer in children and comparison with IOLMaster. Sci Rep 2018; 8:1304. [PMID: 29358637 PMCID: PMC5778016 DOI: 10.1038/s41598-018-19605-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2017] [Accepted: 01/04/2018] [Indexed: 11/09/2022] Open
Abstract
To assess the repeatability and reproducibility of AL-Scan in agreement with those by the IOLMaster in healthy children, two skilled operators measured ocular parameters in 58 children. The parameters included keratometry (K) values, anterior chamber depth (ACD), axial length (AL), central corneal thickness (CCT), pupil diameter (PD), and corneal diameter (CD). The cohort comprised of 32 boys and 26 girls. The AL-Scan measurements showed high repeatability, as the test-retest repeatability (TRT) values of AL, CCT, ACD, Kf, Ks, Km, CD, and PD were 0.09 mm, 5.1 μm, 0.04 mm, 0.28 D, 0.24 D, 0.21 D, 0.39 mm, and 0.22 mm, respectively. The within-subject coefficient of variation (CoV) was low (<0.35%) and the intraclass correlation coefficients (ICC) of all parameters were >0.85. The interobserver reproducibility was excellent with low values of TRT and ICC > 0.95. The CoV of AL, CCT, ACD, and K was <0.22%. The 95% limits of agreement between the AL-Scan and the IOLMaster were narrow for all parameters except for CD. The repeatability and reproducibility of the new biometer, Al-Scan, was excellent for all parameters and can be routinely used in children to measure the biometric values.
Collapse
|
15
|
Comparison of Central Corneal Thickness Measurements Using Ultrasonic Pachymetry, Anterior Segment OCT and Noncontact Specular Microscopy. J Glaucoma 2017; 26:860-865. [PMID: 28834824 DOI: 10.1097/ijg.0000000000000745] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To evaluate and compare central corneal thickness (CCT) values measured with anterior segment optical coherence tomography (AS-OCT), noncontact specular microscopy (NCSM), and ultrasound pachymetry (USP). MATERIALS AND METHODS CCT was measured in 182 healthy eyes without ocular abnormalities other than refractive errors. Three consecutive measurements of CCT by the same examiner were obtained during the same session. The testing sequence of AS-OCT and NCSM was randomly selected. The USP always was performed after the noncontact examinations. RESULTS The average CCT measured by AS-OCT, NCSM, and USP were 535.8±35.5, 547.7±38.2, and 537.4±37.5 μm, respectively. The mean differences between modalities were 11.8±14.7 μm (P<0.01) between NCSM and AS-OCT, 10.3±17.7 μm (P<0.01) between NCSM and USP and 1.6±8.6 μm (P=0.02) between USP and AS-OCT. CONCLUSIONS AS-OCT, NCSM, and USP showed an overall strong agreement in measuring CCT. However, CCT measurements with AS-OCT showed a good correlation to those obtained by USP, NCSM tended to give statistically significant higher CCT readings than either alternative and showed the worse repeatability indices. On the basis of our results, CCT measurement obtained with different instruments cannot be considered directly interchangeable.
Collapse
|
16
|
Teberik K, Eski MT, Kaya M, Ankaralı H. Comparison of central corneal thickness with four different optical devices. Int Ophthalmol 2017; 38:2363-2369. [PMID: 29022163 DOI: 10.1007/s10792-017-0736-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 10/05/2017] [Indexed: 10/18/2022]
Abstract
BACKGROUND To compare the consistency between the average scores of the contact central corneal thickness measurements from ultrasound pachymetry devices still gold standard, such as iPac® and Echoscan US-500, and noncontact measurements via Pentacam HR and Sirius topography. METHODS This prospective study, subsequently admitted to the ophthalmology department, 76 healthy individuals were performed. The measurements were repeated three times for each eye, and average scores were statistically analyzed on the same day and almost at the same time. While measuring the eyes, Pentacam HR, Sirius topography, iPac®, and Echoscan US-500 were used, respectively. The inter-rater agreement of measurements from the devices was assessed with intraclass correlation coefficient, and 95% Confidence Interval and p values demonstrating statistically significance were also presented. In the graphical assessment of the agreement, the Bland-Altman graph was used. RESULTS Among 76 study participants, 43 (56.6%) were composed of women, and age level was 38.6 ± 12.5 years, ranging between 18 and 69. It was observed that the highest agreement was between the measurements obtained from Echoscan US-500 and iPac® devices, but the agreement between the measurements of different devices was higher than 0.90. Bland-Altman graphics were also investigated; the results of four different devices were seen to be consistent with one another. CONCLUSIONS Therefore, the devices we compared in the study can be used as alternatives to one another due to the higher consistency between CCT measurements provided with through UP devices of Echoscan US-500 and iPac®, and Pentacam HR and Sirius topography devices. CLINICAL TRIAL REGISTRATION NUMBER 2016/112.
Collapse
Affiliation(s)
- Kuddusi Teberik
- Department of Ophthalmology, Düzce University Medical School, Orhangazi Mah., Konuralp 500. Cd, No: 125/7, 81450, Düzce, Turkey.
| | - Mehmet Tahir Eski
- Department of Ophthalmology, Düzce University Medical School, Orhangazi Mah., Konuralp 500. Cd, No: 125/7, 81450, Düzce, Turkey
| | - Murat Kaya
- Department of Ophthalmology, Düzce University Medical School, Orhangazi Mah., Konuralp 500. Cd, No: 125/7, 81450, Düzce, Turkey
| | - Handan Ankaralı
- Department of Biostatistics and Medical Informatics, Düzce University Medical School, Düzce, Turkey
| |
Collapse
|
17
|
Kumar M, Shetty R, Jayadev C, Dutta D. Comparability and repeatability of pachymetry in keratoconus using four noncontact techniques. Indian J Ophthalmol 2016; 63:722-7. [PMID: 26632128 PMCID: PMC4705708 DOI: 10.4103/0301-4738.170987] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
PURPOSE To compare and determine the repeatability of central corneal thickness (CCT) measurements using four noncontact pachymetry instruments in eyes with keratoconus. MATERIALS AND METHODS The CCT of consecutive patients with keratoconus was measured during a single visit using the swept source optical coherence tomography (SS-OCT, Casia SS-1000°CT, Tomey, Nagoya, Japan), a rotating Scheimpflug camera system (Pentacam, Oculus Optikgerate GmbH, Wetzlar, Germany), scanning slit topographer (Orbscan IIz topography, Baush and Lomb Surgical Inc., San Dimas, CA, USA), and a hand-held spectral domain OCT (HHSD-OCT, Bioptigen Inc., Durham, North Carolina, USA). Test-retest variability, correlation between measurements and interdevice agreement were analyzed. RESULTS Fifty eyes of 25 participants were analyzed in this study. All measurement methods correlated well with each other (r > 0.9, P < 0.001). Mean ± standard deviation CCT measured by HHSD-OCT, Orbscan IIz, SS-OCT, and Pentacam was 462 ± 41 mm, 458 ± 41 mm, 454 ± 40 mm, and 447 ± 42 mm, respectively. While the HHSD-OCT over-estimated the CCT (P < 0.001), there was a good correlation between the measurements obtained from the other three devices. However, the numerical difference was high and this trend was seen in all the paired comparisons. CONCLUSIONS Though the measurements by different devices correlated well, the numerical agreement may be inadequate for their interchangeable use in clinical practice.
Collapse
Affiliation(s)
- Mukesh Kumar
- Department of Cornea and Refractive Surgery, Narayana Nethralaya Super Specialty Eye Hospital, Bengaluru, Karnataka, India
| | | | | | | |
Collapse
|
18
|
Applications of Scheimpflug Imaging in Glaucoma Management: Current and Potential Applications. J Ophthalmol 2016; 2016:3062381. [PMID: 28044101 PMCID: PMC5164893 DOI: 10.1155/2016/3062381] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2016] [Revised: 09/06/2016] [Accepted: 10/04/2016] [Indexed: 11/24/2022] Open
Abstract
Scheimpflug photography is the basis for a variety of imaging devices that are highly versatile. The applications of Scheimpflug imaging are wide in scope, spanning from evaluation of corneal ectasia to quantifying density in nuclear sclerotic cataracts. The potential uses for Scheimpflug-based devices are expanding and a number of them are relevant in glaucoma. In particular, they can provide three-dimensional image reconstruction of the anterior segment which includes assessment of the iridocorneal angle. Photographic analyses allow also for a noncontact method of estimating central corneal thickness (CCT) and intraocular pressure (IOP), as well as the study of various corneal biomechanical properties, which may be useful for stratifying glaucoma risk.
Collapse
|
19
|
Cleymaet AM, Hess AM, Freeman KS. Comparison between Pentacam-HR and optical coherence tomographycentral corneal thickness measurements in healthy feline eyes. Vet Ophthalmol 2016; 19 Suppl 1:105-14. [PMID: 27370363 DOI: 10.1111/vop.12397] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Allison M. Cleymaet
- Department of Clinical Sciences; College of Veterinary Medicine; Colorado State University; Veterinary Teaching Hospital; 300 West Drake Road Fort Collins CO 80523 USA
| | - Ann M. Hess
- Department of Statistics; College of Natural Sciences; Colorado State University; Veterinary Teaching Hospital; 300 West Drake Road Fort Collins CO 80523 USA
| | - Kate S. Freeman
- Department of Clinical Sciences; College of Veterinary Medicine; Colorado State University; Veterinary Teaching Hospital; 300 West Drake Road Fort Collins CO 80523 USA
| |
Collapse
|
20
|
Altay Y, Balta O, Demirok G, Burcu A, Balta OB, Ornek F. Agreement between Corneal Thickness Measurements Using Pentacam Scheimpflug Camera, Noncontact Specular Microscopy, and Ultrasonographic Pachymetry in Diabetic Patients. Curr Eye Res 2016; 42:187-194. [PMID: 27348734 DOI: 10.3109/02713683.2016.1170854] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
PURPOSE To evaluate the agreement of corneal thickness (CT) measurements obtained by the Pentacam Scheimpflug camera, noncontact specular microscopy (SM), and ultrasonographic pachymetry (UP) in diabetic (DM) patients; and whether duration of diabetes and level of Hb A1c affect the agreement. MATERIALS AND METHODS The CT was measured in 127 patients with DM, and 137 age and sex-matched healthy controls sequentially by Pentacam, SM, and UP. Also diabetic subjects were subdivided according to duration of diabetes and Hb A1c levels. Pearson correlation analysis, linear regression analysis, and Bland-Altman plots were used for examination of agreement. RESULTS We found an excellent and statistically significant correlation of CT measurements between Pentacam-SM (R2 = 0.768; R2 = 0.855), Pentacam-UP (R2 = 0.546; R2 = 0.652), and SM-UP (R2 = 0.759; R2 = 0.797) in diabetic and control groups, respectively. We performed further comparisons of the pair of instruments using the Bland-Altman analysis, and the mean difference between pair of methods was much smaller for SM-UP pair (-4.20 ± 9.79 in diabetic, and -4.58 ± 8.08 in control group). The group having Hb A1c level less than 7.5% showed the best agreement between SM-UP pair as in the control group. Whereas Pentacam-UP showed the best agreement in the group having Hb A1c level ≥7.5%. The best agreement was between Pentacam-UP in 0-4 year group, and between Pentacam-SM in 5-9 year and ≥10 year groups. CONCLUSION SM-UP pair showed a higher agreement in diabetic patients. According to subgroup analyses, Hb A1c level, rather than the duration of diabetes, may determine the agreement of these pachymetry devices. But the difference in CT measurements between devices can still influence clinical diagnosis and treatment. Therefore, these methods are not completely interchangeable.
Collapse
Affiliation(s)
- Yeşim Altay
- a Department of Ophthalmology , Ophthalmologist, Ankara Training and Research Hospital , Ankara , Turkey
| | - Ozgur Balta
- a Department of Ophthalmology , Ophthalmologist, Ankara Training and Research Hospital , Ankara , Turkey
| | - Gülizar Demirok
- b Department of Ophthalmology , Ufuk University Faculty of Medicine , Ankara , Turkey
| | - Ayse Burcu
- a Department of Ophthalmology , Ophthalmologist, Ankara Training and Research Hospital , Ankara , Turkey
| | - Oyku Bezen Balta
- c Department of Family Medicine , Yildirim Beyazit University Faculty of Medicine , Ankara , Turkey
| | - Firdevs Ornek
- a Department of Ophthalmology , Ophthalmologist, Ankara Training and Research Hospital , Ankara , Turkey
| |
Collapse
|
21
|
Briggs S, Bin Moammar M. Effect of 2% fluorescein on Scheimpflug central corneal thickness measurements. Int J Ophthalmol 2016; 9:239-42. [PMID: 26949642 DOI: 10.18240/ijo.2016.02.10] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 12/12/2014] [Indexed: 11/23/2022] Open
Abstract
AIM To assess central corneal thickness (CCT) changes measured with Scheimpflug device following instillation of 2% fluorescein in normal subjects. METHODS This was a prospective randomized study of 60 hospital volunteers. After baseline CCT measurements of both eyes of 40 subjects were obtained using Scheimpflug system, a drop of preservative-free 2% fluorescein, was instilled in one eye and in other eye, one drop of normal saline (control). Measurements were repeated after 1, 2, 5, 10, 20, 30, 40, 50 and 60min (continuous assessment group). Twenty subjects had baseline CCT taken, then fluorescein was instilled in one eye and measurements were taken at 1min. Ten eyes had saline rinse after 1min and 10 other eyes did not, measurements were repeated at 2min (eye rinse group). RESULTS The mean baseline CCT for continuous assessment group was 546.2 ±32.1 µm (range, 489.0-606.0), control eyes was 546.6±30.7 µm (range, 489.0-602.0). At 1min after fluorescein instillation, CCT significantly increased by 37.0±34.0 µm (P<0.001), then decreased gradually, reaching baseline at 60min. CCT variations were not significant in control group (P>0.05). For eye rinse group, CCT mean differences between baseline and 2min were 18.2 µm (95 % CI: -54.7 to 18.3) with rinse and 26.5 µm (95% CI: -62.9 to 9.9) without rinse; paired sample tests were not significant (P>0.05). CONCLUSION The presence of fluorescein increased CCT value to a clinically relevant level of 6.8%. Eye rinse did not significantly reduce the effect at 2min post fluorescein timepoint.
Collapse
Affiliation(s)
- Stella Briggs
- College of Applied Medical Sciences, King Saud University, Riyadh 11433, Saudi Arabia
| | - Marwa Bin Moammar
- Ophthalmology Clinic, Security Forces Hospital, Riyadh 11481, Saudi Arabia
| |
Collapse
|
22
|
Şahin M, Yüksel H, Şahin A, Cingü AK, Türkcü FM, Kaya S, Yazmalar L, Batmaz İ. Evaluation of the Anterior Segment Parameters of the Patients with Scleroderma. Ocul Immunol Inflamm 2016; 25:233-238. [DOI: 10.3109/09273948.2015.1115079] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Muhammed Şahin
- School of Medicine, Department of Ophthalmology, Dicle University, Diyarbakir, Turkey
| | - Harun Yüksel
- School of Medicine, Department of Ophthalmology, Dicle University, Diyarbakir, Turkey
| | - Alparslan Şahin
- School of Medicine, Department of Ophthalmology, Dicle University, Diyarbakir, Turkey
| | - Abdullah Kürşat Cingü
- School of Medicine, Department of Ophthalmology, Dicle University, Diyarbakir, Turkey
| | - Fatih Mehmet Türkcü
- School of Medicine, Department of Ophthalmology, Dicle University, Diyarbakir, Turkey
| | - Savaş Kaya
- Department of Immunology, Dicle University, Diyarbakir, Turkey
| | - Levent Yazmalar
- Department of Physical Medicine and Rehabilitation, Dicle University, Diyarbakir, Turkey
| | - İbrahim Batmaz
- Department of Physical Medicine and Rehabilitation, Dicle University, Diyarbakir, Turkey
| |
Collapse
|
23
|
Ramamurthy S, Reddy JC, Jhanji V. Topography and tomography in the diagnosis of corneal ectasia. EXPERT REVIEW OF OPHTHALMOLOGY 2015. [DOI: 10.1586/17469899.2015.1044979] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
|
24
|
Pentacam vs SP3000P specular microscopy in measuring corneal thickness. Cont Lens Anterior Eye 2014; 38:21-7. [PMID: 25240777 DOI: 10.1016/j.clae.2014.08.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2013] [Revised: 08/01/2014] [Accepted: 08/28/2014] [Indexed: 11/20/2022]
Abstract
PURPOSE To compare corneal thickness (CT) measurements obtained with SP3000P specular microscope and Pentacam in eyes screened to undergo refractive surgery (RS). METHODS In this prospective study, a non-randomized consecutive series of 73 healthy eyes (age range: 14-78 years; mean=38.4±14.9) underwent CT measurement with both Oculus Pentacam and Topcon SP3000P specular microscope to assess their suitability to undergo corneal RS. RESULTS CT measurements with SP3000P ranged from 451 to 609 μs (mean 523.1±34.4 μs). The measurements obtained with Pentacam ranged at the corneal apex from 477 to 672 μs (mean 558.9±38.9 μs), at the pupil center from 477 to 672 μs (mean 557.9±38.9 μs) and at the thinnest point from 474 to 669 μs (mean 551.1±39.4 μs). CT measurements showed a good correlation but a statistically significant difference at the pupil center (mean -34.9±14.6 μs, R(2)=0.860, p<0.001), at the apex (mean -35.9±14.9 μs, R(2)=0.856, p<0.001) and at the thinnest point (mean -32±14.8 μs, R(2)=0.862, p<0.001). The calculated regression formulas were: y=0.816x+66.94 for the apex, y=0.819x+66.07 for the pupil center and y=0.810x+73.13 for the thinnest point; where y is the CT measured with the SP3000P and x is the measurement obtained with the Oculus Pentacam. CONCLUSIONS Our results suggest that SP3000P measures thinner corneas compared to the Pentacam and that the correcting factor we identified should be applied to make comparisons between these two devices.
Collapse
|
25
|
Saenz-Frances F, Bermúdez-Vallecilla MC, Borrego-Sanz L, Jañez L, Martinez-de-la-Casa JM, Morales-Fernandez L, Santos-Bueso E, Garcia-Sanchez J, Garcia-Feijoo J. Anatomical characterization of central, apical and minimal corneal thickness. Int J Ophthalmol 2014; 7:668-72. [PMID: 25161940 DOI: 10.3980/j.issn.2222-3959.2014.04.15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 03/12/2014] [Indexed: 11/02/2022] Open
Abstract
AIM To anatomically locate the points of minimum corneal thickness and central corneal thickness (pupil center) in relation to the corneal apex. METHODS Observational, cross-sectional study, 299 healthy volunteers. Thickness at the corneal apex (AT), minimum corneal thickness (MT) and corneal thickness at the pupil center (PT) were determined using the pentacam. Distances from the corneal apex to MT (MD) and PT (PD) were calculated and their quadrant position (taking the corneal apex as the reference) determined: point of minimum thickness (MC) and point of central thickness (PC) depending on the quadrant position. Two multivariate linear regression models were constructed to examine the influence of age, gender, power of the flattest and steepest corneal axes, position of the flattest axis, corneal volume (determined using the Pentacam) and PT on MD and PD. The effects of these variables on MC and PC were also determined in two multinomial regression models. RESULTS MT was located at a mean distance of 0.909 mm from the apex (79.4% in the inferior-temporal quadrant). PT was located at a mean distance of 0.156 mm from the apex. The linear regression model for MD indicated it was significantly influenced by corneal volume (B=-0.024; 95%CI: -0.043 to -0.004). No significant relations were identified in the linear regression model for PD or the multinomial logistic regressions for MC and PC. CONCLUSION MT was typically located at the inferior-temporal quadrant of the cornea and its distance to the corneal apex tended to decrease with the increment of corneal volume.
Collapse
Affiliation(s)
- Federico Saenz-Frances
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| | | | - Lara Borrego-Sanz
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Luis Jañez
- Instituto de Tecnología del Conocimiento, Universidad Complutense de Madrid, Madrid 28040, Spain
| | | | - Laura Morales-Fernandez
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Enrique Santos-Bueso
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Julián Garcia-Sanchez
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| | - Julián Garcia-Feijoo
- Department of Ophthalmology, Hospital Clínico San Carlos, Universidad Complutense de Madrid, Madrid 28040, Spain
| |
Collapse
|
26
|
Comparison and Evaluation of Central Corneal Thickness Using 2 New Noncontact Specular Microscopes and Conventional Pachymetry Devices. Cornea 2014; 33:576-81. [DOI: 10.1097/ico.0000000000000113] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
27
|
Salim S, Du H, Wan J. Comparison of central corneal thickness measured by hand-held and desk-mounted ultrasound pachymeters in glaucoma patients. Semin Ophthalmol 2014; 30:268-71. [PMID: 24409944 DOI: 10.3109/08820538.2013.839816] [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: 11/13/2022]
Abstract
PURPOSE The purpose of this study was to compare the accuracy and reproducibility of central corneal thickness measured by hand-held and desk-mounted ultrasound pachymeter in glaucoma patients under treatment. METHODS Prospective study of 65 glaucoma patients. Central corneal thickness was measured by two ultrasound pachymeters: the hand-held, portable PachPen (Accutome, Lynwood, WA), and the desk-mounted PacScan 300 (Sonomed, Lake Success, NY). RESULTS The mean ± SD central corneal thickness was 526.5 ± 44.8 µm and 530.0 ± 44.7 µm for the hand-held and desk-mounted pachymeters, respectively (p = 0.15). Linear regression analysis revealed a slope of 0.97 with Pearson correlation coefficient of 0.96. Bland-Altman analysis showed a mean difference of measurements by both pachymeters of 3.22 µm with two standard deviations = 9.51. Both instruments showed high intraobserver correlation: 0.972 for the hand-held pachymeter and 0.993 for the desk-mounted pachymeter. CONCLUSION Central corneal thickness measurements were comparable with the use of hand-held and desk-mounted ultrasound units in glaucoma patients with good intraobserver reproducibility.
Collapse
Affiliation(s)
- Sarwat Salim
- University of Tennessee Health Science Center , Memphis, TN , USA
| | | | | |
Collapse
|
28
|
|
29
|
Yazıcı AT, Pekel G, Bozkurt E, Yıldırım Y, Pekel E, Demirok A, Yılmaz OF. Measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients. Int J Ophthalmol 2013; 6:521-5. [PMID: 23991390 DOI: 10.3980/j.issn.2222-3959.2013.04.21] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 06/18/2013] [Indexed: 11/02/2022] Open
Abstract
AIM To evaluate the measurements of anterior segment parameters using three different non-contact optical devices in keratoconus patients. METHODS A hundred and one eyes of 55 keratoconus patients were enrolled in this study. The mean age was 26.2±8.9 years. The inclusion criteria were keratoconus stage I to III according to the Amsler-Krumeich keratoconus classification. All the measurements were done by the same operator, under the mesopic light condition and repeated with three different optical methods; Visante, Orbscan and Pentacam. The evaluated anterior segment parameters were anterior chamber depth (ACD), central and thinnest corneal thickness (CCT and TCT) and pupil diameter (PD). RESULTS THE MEAN CCT MEASURED BY VISANTE, ORBSCAN AND PENTACAM WERE AS FOLLOWS: 462.0±48.1µm, 463.9±60.9µm, 476.5±45.3µm, respectively (P=0.873). The mean ACD values were 3.34±0.33mm, 3.26±0.33mm, 3.49±0.40mm, respectively (P=0.118). The mean PD measurements were 5.11±1.14mm, 4.80±0.85mm, 3.80±1.38mm, respectively (P<0.001). The mean TCT measurements of Visante, Orbscan and Pentacam were 437.9±48.2µm, 447.6±60.6µm and 459.9±44.0µm, respectively (P=0.214). The Visante and Orbscan measured CCT similarly, while Pentacam measured CCT thicker than the other two. The Visante measured TCT thinner than the other two devices. In ACD measurements, Orbscan was the one giving the lowest values. PD was measured differently by the devices. CONCLUSION Although TCT, CCT and ACD measurements acquired by Visante, Orbscan and Pentacam in keratoconus patients are similar, PD measurements show large differences among the devices.
Collapse
|
30
|
Fukuda R, Usui T, Miyai T, Mori Y, Miyata K, Amano S. Corneal Thickness and Volume Measurements by Swept Source Anterior Segment Optical Coherence Tomography in Normal Subjects. Curr Eye Res 2013; 38:531-6. [DOI: 10.3109/02713683.2012.745878] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
31
|
Luo YH, Zhong Q, Ouyang PB, Guo XJ, Duan XC. Repeatability and agreement of CCT measurement in myopia using entacam and ultrasound pachymetry. Int J Ophthalmol 2012; 5:329-33. [PMID: 22773982 DOI: 10.3980/j.issn.2222-3959.2012.03.15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2012] [Accepted: 05/07/2012] [Indexed: 11/02/2022] Open
Abstract
AIM To evaluate the repeatability of central corneal thickness (CCT) measurement by entacam, and agreement of CCT measured by Pentacam and ultrasound pachymetry (USP) in Chinese myopia. Thereby investigate the possibility of Pentacam as a substitute for USP in CCT measurement before refractive surgery. The effects of corneal curvature measured by Pentacam on CCT were also evaluated. METHODS One hundred and forty-eight right eyes of 148 individual with myopia were included in this study. Three successive Pentacam CCT measurements followed by 10 successive ultrasound pachymetry were carried out in the 148 eyes. Mean of CCT taken by each device was calculated for comparison. According to the CCT measured by USP, all the 148 eyes were divided into 3 groups: <520µm, 520-560µm, >560µm. For all eyes and each group the CCT obtained by Pentacam and USP were compared. Anterior corneal curvature of the 148 eyes was also adopted for correlation analysis with CCT obtained by ultrasound pachymetry. In addition, CCT measurement using 60 random selected Scheimpflug images was performed by 3 skilled investigators at different time, and this was repeated for 3 times by a forth investigator to assess repeatability of Pentacam CCT measurement using Scheimpflug images. RESULTS Intraclass correlation coefficient (ICC) analysis revealed high intraobserver repeatability (ICC=0.994, F=158.60, P<0.001) for CCT measurement by Pentacam. The interobserver (ICC=0.998, F=494.73, P<0.001) and intraobserver (ICC=0.997, F=383.98, P<0.001) repeatability for Pentacam CCT measurements using Scheimpflug images were also excellent. There was high positive correlation between the CCT values measured by Pentacam and ultrasound pachymetry (r=0.963, P<0.001). Bland-altman plots showed that the Pentacam underestimate the CCT by 8.02µm compared with ultrasouond pachymetry. The differences between Pentacam and USP increased as the CCT readings by USP increased (Pentacam vs USP: slope=-0.04, P<0.05). The 95% upper and lower limits of agreement between CCT values obtained from the two devices were +9.33µm and -25.37µm. No significant association could be found between CCT and anterior corneal curvature. CONCLUSION Inter- and intraobserver variability for CCT measurements by Pentacam was considerably below clinically significant levels. CCT of myopia obtained by Scheimpflug camera, Pentacam, were highly correlated to that by ultrasound pachymetry. However, the values obtained are not directly interchangeable between Pentacam and ultrasound pachymetry as the 95% limits of agreement are relatively wide. Pentacam can be a useful instrument for measuring CCT in candidates to refractive surgery in clinic.
Collapse
Affiliation(s)
- Yong-Heng Luo
- Department of Ophthalmology, the Second Xiangya Hospital, Central South University, Changsha 410011, Hunan Province, China
| | | | | | | | | |
Collapse
|
32
|
|
33
|
Abstract
PURPOSE This study aimed to compare central corneal thickness (CCT) measurement by Tonopachy to that by Pentacam and ultrasound pachymetry, and intraocular pressure (IOP) measurement to that by Goldmann applanation tonometry (GAT). The reproducibility of CCT and IOP measurements by Tonopachy was also evaluated. METHODS In 104 eyes of 104 patients, CCT was measured by Tonopachy, Pentacam, and ultrasound pachymetry, and IOP was measured by Tonopachy and GAT. Each CCT and IOP measurement was compared using Pearson correlation, repeated measures analysis of variance, and Bland-Altman plots. In 30 subjects, CCT and IOP measurements by Tonopachy were repeated to evaluate intrasession and intraobserver variability. RESULTS Both CCT and IOP measurements were highly correlated among all instruments used in this study. CCT measurements by three pachymeters were statistically different (p<0.0001). CCT measured by ultrasound pachymetry was lowest (541.7 ± 30.6 μm) whereas those by Tonopachy and Pentacam showed no difference (557.3 ± 34.3 and 558.0 ± 33.7 μm, respectively). Tonopachy overestimated CCT by 13.9 μm when compared with ultrasound pachymetry. There was a statistically significant difference between IOP measurements by two tonometers (p<0.0001); IOP measurement was higher by Tonopachy than by GAT (13.9 ± 4.2 and 12.5 ± 3.2 mm Hg, respectively). Tonopachy overestimated IOP measurements by 1.2 mm Hg compared with GAT. Intersession agreements for IOP and CCT measurements by Tonopachy were excellent (intraclass correlation, 0.902 and 0.962, respectively) with 95% limits of agreement ranging from -1.4 to 2.2 mm Hg and from -12.9 to 12.1 μm, respectively. CONCLUSIONS Although CCT and IOP measurements obtained by Tonopachy were reproducible and showed close agreement with ultrasound pachymetry and Pentacam, and GAT, careful attention should be paid when comparing Tonopachy CCT measurement to ultrasound pachymetry or its IOP measurement to GAT as the values may not be interchangeable. Tonopachy is a reliable instrument for evaluating CCT and IOP.
Collapse
|
34
|
Almubrad TM, Osuagwu UL, AlAbbadi I, Ogbuehi KC. Comparison of the precision of the Topcon SP-3000P specular microscope and an ultrasound pachymeter. Clin Ophthalmol 2011; 5:871-6. [PMID: 21760714 PMCID: PMC3133003 DOI: 10.2147/opth.s21247] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Indexed: 11/23/2022] Open
Abstract
AIM To compare the precision of the Topcon SP-3000P noncontact specular microscope (NCSM) and the DGH 500 ultrasound pachymeter (USP). METHODS Triplicate measurements of central corneal thickness (CCT) for 100 eyes were taken with an NCSM and a USP in 2 visits separated by 1 week. Repeatability was assessed by computing the differences between all 3 readings from each subject. Coefficients of repeatability and reproducibility were computed. RESULTS MEAN CCT AS MEASURED BY EACH INSTRUMENT WERE: 518.53 ± 34.96 μm (range 417.33-592.67) and 516.94 ± 33.60 μm (range 431.67-582.67) for sessions 1 and 2 respectively, with the NCSM; 546.69 ± 36.62 μm (range 457.33-617.00) and 549.78 ± 35.26 μm (range 454.00-618.67) for sessions 1 and 2 respectively, with the USP. The ultrasound CCT measurements were consistently higher than those obtained with the NCSM in both sessions 28.17 ± 19.20 μm (mean ± SD, session 1) and 32.81 ± 14.04 (mean ± SD, session 2). The repeatability coefficient for the NCSM was better in both sessions than those for USP (±10 μm vs ± 12 μm in session 1 and ±8 μm vs ±10 μm in session 2). The reproducibility coefficient with the NCSM was half that with the USP (±21 μm vs ±41 μm). CONCLUSION The SP-3000P NCSM is a more precise and reproducible instrument for measurement of CCT than the USP, but both instruments are reliable, useful instruments for measuring CCT.
Collapse
Affiliation(s)
- Turki M Almubrad
- Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Uchechukwu L Osuagwu
- Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Ibrahim AlAbbadi
- Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| | - Kelechi C Ogbuehi
- Cornea Research Chair, Department of Optometry, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia
| |
Collapse
|
35
|
Comparison of Oculus Pentacam and Stratus Optical Coherence Tomography for Measurement of Central Corneal Thickness. Cornea 2011; 30:670-4. [PMID: 21242780 DOI: 10.1097/ico.0b013e31820128a4] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
36
|
Abstract
PURPOSE To assess the degrees of agreement in measuring corneal thickness in normal eyes between 2 noncontact systems based on the dual Scheimpflug system (Galilei; Ziemer) and rotating Scheimpflug imaging (HR Pentacam; Oculus) and also between each of these methods and the gold-standard method of ultrasound pachymetry. METHODS In a prospective study, measurement agreement was assessed in 47 eyes of 47 healthy subjects. All eyes were examined with each of the 3 devices. Measurements made with the Galilei and HR Pentacam were compared with those made with ultrasound. The central corneal thickness (CCT) and thinnest pachymetry of the Galilei and HR Pentacam were also compared. RESULTS The mean values of CCT obtained from Galilei, HR Pentacam, and ultrasound were 560.57 ± 29.10, 542.31 ± 30.50, and 548.61 ± 29.92 μm, respectively. The 95% limits of agreement of each of these devices with ultrasound were -11.03 and +34.94 μm for the Galilei and -33.67 and +20.74 μm for the Pentacam. The 95% limits of agreement of Galilei with Pentacam in measurement of central and thinnest corneal thickness were -3.39 and +33.11 and -10.40 and +27.29 μm, respectively. Although CCT measurements made with the HR Pentacam were thinner (P < 0.001), and those obtained with Galilei were thicker (P < 0.001) than those made with ultrasound, there were significant correlation between Galilei and ultrasound (r = 0.92; P < 0.0001) and between HR Pentacam and ultrasound (r = 0.89; P < 0.0001). The central and thinnest corneal thickness measurements made with the HR Pentacam were thinner (P < 0.0001) than those made with Galilei, but there was a significant correlation between Galilei and HR Pentacam in measuring CCT (r = 0.96; P < 0.0001) and thinnest corneal thickness (r = 0.95; P < 0.0001). Bland-Altman plots showed good agreement between these methods. CONCLUSIONS Although differences between the devices were statistically significant, there was good correlation and agreement between Galilei and Pentacam in measuring central and thinnest corneal thickness. The corneal thickness measurements made with the HR Pentacam and Galilei also showed good correlation and agreement with those made with ultrasound.
Collapse
|
37
|
Al-Mezaine HS, Al-Amro SA, Kangave D, Al-Obeidan S, Al-Jubair KM. Comparison of central corneal thickness measurements using Pentacam and ultrasonic pachymetry in post-LASIK eyes for myopia. Eur J Ophthalmol 2010; 20:852-7. [PMID: 20815096 DOI: 10.1177/112067211002000507] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE To compare central corneal thickness (CCT) measurements obtained using the Pentacam Scheimpflug system with those obtained using DGH ultrasound pachymetry (UP) in post-laser in situ keratomileusis (LASIK) eyes for myopia. METHODS In a prospective study, measurement agreement was assessed in 143 eyes of 72 post-LASIK patients using both the Pentacam and UP at the Eye Consultants Center in Riyadh, Saudi Arabia. RESULTS The mean CCT was 522 +/- 42.2 microm with the Oculus Pentacam and 516.2 +/- 40.6 microm with UP. The Bland-Altman plot showed that the mean +/- SD for the differences between the 2 devices was 5.8 +/- 13.6 microm, with 95% confidence interval limits ranging from -20.9 microm to 32.6 microm. A test of statistical significance indicated that the mean differences of 5.8 +/- 13.6 microm differed significantly from zero (p<0.001; Wilcoxon signed-rank test), thus indicating that the Pentacam measurements tended to overestimate CCT compared with UP. Analysis of regression showed a high correlation between the values obtained with both devices (r=0.947, p<0.001). CONCLUSIONS In post-LASIK myopic eyes, although a high correlation has been shown between Pentacam and UP measurements, Pentacam tends to overestimate CCT compared to UP. Pentacam probably cannot be used interchangeably with UP in post-LASIK eyes for myopia.
Collapse
Affiliation(s)
- Hani S Al-Mezaine
- Department of Ophthalmology, College of Medicine, King Saud University, Riyadh, Saudi Arabia.
| | | | | | | | | |
Collapse
|
38
|
Módis L, Szalai E, Németh G, Berta A. Evaluation of a recently developed noncontact specular microscope in comparison with conventional pachymetry devices. Eur J Ophthalmol 2010; 20:831-8. [PMID: 20213610 DOI: 10.1177/112067211002000504] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE The study was conducted to assess the central corneal thickness (CCT) of the healthy cornea with a recently developed noncontact specular microscope (EM-3000; Tomey) and compare the results with those measured with a contact specular microscope and an ultrasound pachymeter. Agreement between measurements taken by 2 investigators was also studied. METHODS The right eyes of 41 healthy individuals who had negative history of contact lens wear, ophthalmic disease, or ocular surgery were examined. The CCT was determined sequentially with a noncontact specular microscope, a contact specular microscope (EM-1000; Tomey), and an ultrasound pachymeter (AL-2000; Tomey). Each evaluation with the specular microscopes was performed by 2 independent operators. RESULTS A significant difference was detected in pachymetry measurements among the 3 instruments (p=0.01; analysis of variance). The mean CCT values were lower measured with the ultrasound pachymeter (537+/-30 microm) than the contact endothelial microscope (543+/-37 microm, p=0.17, Student t-test) and the noncontact microscope (549+/-33 microm, p<0.0001) (operator 1). There was no statistically significant difference in CCT measurements between the 2 endothelial microscopes (p=0.19). We found significant correlations (p<0.0001) in thickness measurements between each pair of instruments (r=0.91, noncontact microscopy and ultrasound pachymetry; r=0.74, noncontact and contact microscopy; r=0.72, contact microscopy and ultrasound pachymetry; Spearman rank correlation). CONCLUSIONS The strong correlations among the 3 pachymetry devices suggest that the tested instruments provide reliable measurements; however, they cannot be used interchangeably.
Collapse
Affiliation(s)
- László Módis
- Department of Ophthalmology, Medical and Health Science Center, University of Debrecen, Debrecen, Hungary.
| | | | | | | |
Collapse
|
39
|
Grewal DS, Brar GS, Grewal SPS. Assessment of central corneal thickness in normal, keratoconus, and post-laser in situ keratomileusis eyes using Scheimpflug imaging, spectral domain optical coherence tomography, and ultrasound pachymetry. J Cataract Refract Surg 2010; 36:954-64. [PMID: 20494767 DOI: 10.1016/j.jcrs.2009.12.033] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2009] [Revised: 11/02/2009] [Accepted: 12/07/2009] [Indexed: 11/29/2022]
Abstract
PURPOSE To compare the central corneal thickness (CCT) in normal eyes, eyes with keratoconus, and eyes after laser in situ keratomileusis (LASIK) using 3 methods. SETTING Cornea Clinic, Grewal Eye Institute, Chandigarh, India. METHODS In this study, CCT was measured by sequential Scheimpflug imaging, spectral-domain anterior segment optical coherence tomography (AS-OCT), and ultrasound (US) pachymetry. RESULTS Each of the 3 groups comprised 50 eyes. There were no differences between the 3 groups in age, sex, or intraocular pressure. In normal eyes, CCT was statistically significantly higher by US pachymetry (mean 525.8 microm +/- 41.4) [SD] than by Scheimpflug imaging (mean 519.4 +/- 40.9 microm) and AS-OCT (mean 517.9 +/- 41.5 microm) (both P<.001). In keratoconus eyes, CCT by US pachymetry (mean 446.4 +/- 57.9 microm) was statistically significantly higher than by Scheimpflug imaging (mean 439.6 +/- 62.1 microm) (P = .002) and AS-OCT (mean 441.8 +/- 58.4 microm) (P = .007). In post-LASIK eyes CCT by US pachymetry (mean 462.4 +/- 44.7 microm) was significantly higher than by Scheimpflug imaging (mean 457.9 +/- 33.6 microm) (P = .012) and AS-OCT (mean 455.4 +/- 43.2 microm) (P<.001). In all groups, CCT measured by Scheimpflug imaging and AS-OCT was similar. CONCLUSIONS There was a statistically significant difference between Scheimpflug imaging and US pachymetry and AS-OCT, with US pachymetry measurements being consistently thicker. Thus, CCT should be interpreted in the context of the instrument used.
Collapse
|
40
|
Yazici AT, Bozkurt E, Alagoz C, Alagoz N, Pekel G, Kaya V, Yilmaz OF. Central Corneal Thickness, Anterior Chamber Depth, and Pupil Diameter Measurements Using Visante OCT, Orbscan, and Pentacam. J Refract Surg 2010; 26:127-33. [PMID: 20163077 DOI: 10.3928/1081597x-20100121-08] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2008] [Accepted: 02/02/2009] [Indexed: 11/20/2022]
|
41
|
Discrepancy between central and midperipheral corneal thickness measurements obtained with slit-scanning pachymetry and noncontact specular microscopy. J Cataract Refract Surg 2009; 35:2127-35. [DOI: 10.1016/j.jcrs.2009.07.012] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 07/02/2009] [Accepted: 07/08/2009] [Indexed: 11/22/2022]
|
42
|
Comparison of central corneal thickness measurements by Pentacam, noncontact specular microscope, and ultrasound pachymetry in normal and post-LASIK eyes. Saudi J Ophthalmol 2009; 23:181-7. [PMID: 23960858 DOI: 10.1016/j.sjopt.2009.10.002] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Accepted: 08/28/2009] [Indexed: 11/22/2022] Open
Abstract
PURPOSE To compare central corneal thickness (CCT) measurements taken with Pentacam, noncontact specular microscope (NCSM), and ultrasound pachymetry (US) in normal and post-laser in situ keratomileusis (LASIK) eyes and to assess the agreement between the three devices. DESIGN Prospective clinical trial. PATIENTS AND METHODS Central corneal thickness (CCT) was measured in 94 eyes of normal volunteer and in 72 eyes of post-LASIK patients. Measurements were made with the three devices. RESULTS In normal eyes, the mean (±SD) CCT taken with Pentacam, NCSM, and US was 552.6 ± 36.8 μm, 511.9 ± 38.6 μm, and 533.3 ± 37.9 μm, respectively. The average values of CCT taken with the three instruments were significantly different. In post-LASIK eyes the mean CCT with Pentacam, NCSM, and US was 483.02 ± 6.03 μm, 450.7 ± 5.3 μm, and 469.5 ± 5.8 μm, respectively. The average values of CCT taken were significantly different for Pentacam vs. NCSM (P = 0.046) and Pentacam vs. US (P = 0.02), but not significant for NCSM vs. US (P = 0.352). The Bland and Altman method for assessing clinical agreement between 3 instruments showed that in normal eyes, the mean values and paired differences of the three CCT devices were found to be statistically independent. In post-LASIK eyes, there was significant association between the difference and the mean of the Pentacam and NCSM, and US and NCSM. CONCLUSION The three devices cannot be used interchangeably in normal and post-LASIK eyes. Pentacam tends to give significantly thicker reading than ultrasound pachymetry.
Collapse
|
43
|
Doors M, Cruysberg LPJ, Berendschot TTJM, de Brabander J, Verbakel F, Webers CAB, Nuijts RMMA. Comparison of central corneal thickness and anterior chamber depth measurements using three imaging technologies in normal eyes and after phakic intraocular lens implantation. Graefes Arch Clin Exp Ophthalmol 2009; 247:1139-46. [PMID: 19404662 PMCID: PMC2709228 DOI: 10.1007/s00417-009-1086-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2008] [Revised: 03/23/2009] [Accepted: 04/06/2009] [Indexed: 11/28/2022] Open
Abstract
Background The repeatability and interchangeability of imaging devices measuring central corneal thickness (CCT) and anterior chamber depth (ACD) are important in the assessment of patients considering refractive surgery. The purpose of this study was to investigate the agreement of CCT and ACD measurements using three imaging technologies in healthy eyes and in eyes after phakic intraocular lens implantation (pIOL). Methods In this comparative study, CCT and ACD were measured using anterior segment optical coherence tomography (AS-OCT), Orbscan II, and Pentacam in 33 healthy volunteers (66 eyes) and 22 patients (42 eyes) after pIOL implantation. Intraobserver repeatability was evaluated for all three devices in the healthy volunteer group. Results Pairwise comparison of CCT measurements showed significant differences between all devices (P < 0.001), except for the AS-OCT and Orbscan II in the healthy volunteer group (P = 0.422) and the Orbscan II and Pentacam in the pIOL group (P = 0.214). ACD measurements demonstrated significant differences between all pairwise comparisons in both groups (P ≤ 0.001). Intraobserver reliability was high for CCT and ACD measurements in the healthy volunteer group, with coefficients of variation ranging from 0.6% to 1.2% and 0.4% to 0.5% respectively. Conclusions CCT and ACD measurements using AS-OCT, Orbscan II, and Pentacam demonstrated high intraobserver reliability. However, these devices should not be used interchangeably for measurements of CCT and ACD in healthy subject and patients after pIOL implantation.
Collapse
Affiliation(s)
- Muriël Doors
- Department of Ophthalmology, University Hospital Maastricht, P. Debyelaan 25, 6202 AZ, Maastricht, The Netherlands
| | | | | | | | | | | | | |
Collapse
|
44
|
Kwon SM, Oh HC, Lee DJ, Jeung WJ, Rho SH. Comparision of Anterior Segment Parameters in Angle-Closure Glaucoma Using Scheimpflug Camera. JOURNAL OF THE KOREAN OPHTHALMOLOGICAL SOCIETY 2009. [DOI: 10.3341/jkos.2009.50.1.128] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Affiliation(s)
- Sang Min Kwon
- Department of Ophthalmology, Dong-A University College of Medicine, Pusan, Korea
| | - Hyun Chul Oh
- Department of Ophthalmology, Dong-A University College of Medicine, Pusan, Korea
| | - Dong Joon Lee
- Department of Ophthalmology, Dong-A University College of Medicine, Pusan, Korea
| | - Woo Jin Jeung
- Department of Ophthalmology, Dong-A University College of Medicine, Pusan, Korea
| | - Sae Heun Rho
- Department of Ophthalmology, Dong-A University College of Medicine, Pusan, Korea
| |
Collapse
|
45
|
Al-Mezaine HS, Al-Amro SA, Kangave D, Sadaawy A, Wehaib TA, Al-Obeidan S. Comparison between central corneal thickness measurements by oculus pentacam and ultrasonic pachymetry. Int Ophthalmol 2008; 28:333-8. [PMID: 17898935 DOI: 10.1007/s10792-007-9143-9] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2007] [Accepted: 08/23/2007] [Indexed: 11/26/2022]
Abstract
PURPOSE To compare the accuracy of central corneal thickness (CCT) measurements by the oculus pentacam scheimpflug system, with those obtained with the DGH ultrasound pachymeter (UP) and to assess the agreement between the two devices. METHODS In a prospective study, measurement agreement was assessed in 984 eyes of 492 healthy subjects using both oculus pentacam and ultrasonic pachymetry at the Eye Consultants Center, Riyadh, Saudi Arabia. RESULT In the measurement agreement experiment, the mean CCT was 552.4 +/- 37.0 microm with oculus pentacam and 544.1 +/- 35.4 microm with ultrasonic pachymetry. Regression analysis showed a high correlation between the values obtained with both devices (r = 0.912, P < 0.001). Compared with UP, pentacam overestimated the CCT by a mean of 8.2 microm as demonstrated in a Bland-Altman plot. CONCLUSION the CCT measurements by the pentacam and UP are highly correlated. The pentacam agrees well with UP and is a reliable alternative to UP in CCT measurements.
Collapse
Affiliation(s)
- Hani S Al-Mezaine
- Department of Ophthalmology, College of Medicine, King Saud University, PO Box 230387, Riyadh, 11321, Saudi Arabia.
| | | | | | | | | | | |
Collapse
|
46
|
Matsuda J, Hieda O, Kinoshita S. Comparison of central corneal thickness measurements by Orbscan II and Pentacam after corneal refractive surgery. Jpn J Ophthalmol 2008; 52:245-249. [DOI: 10.1007/s10384-008-0550-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2007] [Accepted: 01/24/2008] [Indexed: 10/21/2022]
|
47
|
Li H, Leung CKS, Wong L, Cheung CYL, Pang CP, Weinreb RN, Lam DSC. Comparative study of central corneal thickness measurement with slit-lamp optical coherence tomography and visante optical coherence tomography. Ophthalmology 2008; 115:796-801.e2. [PMID: 17916376 DOI: 10.1016/j.ophtha.2007.07.006] [Citation(s) in RCA: 91] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2007] [Revised: 06/28/2007] [Accepted: 07/05/2007] [Indexed: 01/22/2023] Open
Abstract
PURPOSE To evaluate the repeatability and reproducibility of central corneal thickness (CCT) measurements obtained by 2 anterior segment optical coherence tomography (OCT) imaging systems and to examine their agreements with ultrasound pachymetry. DESIGN Observational cross-sectional study. PARTICIPANTS Fifty eyes from 50 healthy normal subjects were recruited. METHODS In one randomly selected eye in each subject, CCT was measured by slit-lamp OCT (SLOCT), Visante OCT, and ultrasound pachymetry. For anterior segment OCT measurements, both automatic and manual CCTs were obtained. Twenty-five of the 50 subjects were invited for 2 more visits within a week to evaluate repeatability and reproducibility of CCT measurement. MAIN OUTCOME MEASURES Central corneal thickness measurement obtained by the 3 methods and their agreements. Intrasession and intersession within-subject standard deviation (S(w)), precision (1.96xS(w)), coefficient of variation (CV(w)) (100xS(w)/overall mean), and intraclass correlation coefficient (ICC) were calculated to evaluate repeatability and reproducibility. RESULTS Good repeatability and reproducibility were found for both automatic and manual CCT measurements obtained by SLOCT and Visante OCT. For intrasession repeatability, CV(w) and ICC values ranged between 0.9% and 1.2% and 0.96 and 0.98, respectively. For intersession reproducibility, the respective CV(w) and ICC values ranged between 1.2% and 1.4% and 0.94 and 0.96. Although no significant difference was found between automatic/manual SLOCT measurements and ultrasound pachymetry, automatic Visante OCT CCT (535.7+/-30.2 microm) was significantly less than CCT with ultrasound pachymetry (550.3+/-31.14 microm) (P<0.001). In contrast, manual Visante OCT measurement (558.8+/-32.8 microm) was slightly higher than ultrasound pachymetry (P<0.001). Nevertheless, SLOCT and Visante OCT measurement of CCT had 95% limits of agreement comparable to that of ultrasound pachymetry. The best agreement was observed in the manual SLOCT measurement (95% limits of agreement between -15.5 and 11.7 microm). CONCLUSIONS Both SLOCT and Visante OCT automatic and manual CCT measurements were reliable and showed comparable agreement with ultrasound pachymetry. Although the 2 anterior segment OCT imaging systems have similar design and working principles, clinicians should be aware of the differences in CCT measurement between the 2 anterior segment OCTs.
Collapse
Affiliation(s)
- Haitao Li
- Department of Ophthalmology and Visual Sciences, Chinese University of Hong Kong, Hong Kong, China
| | | | | | | | | | | | | |
Collapse
|
48
|
Ho JD, Tsai CY, Tsai RJF, Kuo LL, Tsai LI, Liou SW. Validity of the keratometric index: Evaluation by the Pentacam rotating Scheimpflug camera. J Cataract Refract Surg 2008; 34:137-45. [DOI: 10.1016/j.jcrs.2007.09.033] [Citation(s) in RCA: 109] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Accepted: 09/01/2007] [Indexed: 11/27/2022]
|