Correlation of Anterior Segment Parameters in Keratoconus Patients

ABSTRACT Purpose To evaluate the corneal asphericity, volume, thickness and keratometry and the correlation among these variables in keratoconus patients. Materials and methods A total of 1,071 eyes of 810 patients diagnosed with keratoconus were evaluated with a Pentacam (Oculus Optikgerate GmbH). Five groups were established according to the mean keratometry readings: Very mild [K < 44.0 diopters (D)], mild (K = 44.0-47.0D), moderate (K = 47.0-52.0D), severe (K = 52.0-60.0D) and very severe (K = 60.0 or higher). The following parameters were obtained: Anterior corneal asphericity (Q), corneal volume (CV) and thinnest corneal thickness (TCT). Results Sixty-six eyes had very mild keratoconus, 269 had mild keratoconus, 465 had moderate keratoconus, 233 had severe keratoconus and 38 had very severe keratoconus. As the severity of disease increases, there is an increment in K and CV values and reduction of Q and TCT. There was a statistically significant difference in values for all parameters, except the CV. The Pearson correlation index showed an inverse correlation between the degree of keratoconus and the asphericity (Q), i.e. the more severe the keratoconus the more negative the Q-value. Only in the very severe group there was no statistically significant correlation between K and Q. There was no correlation between severity of keratoconus and CV. There was an inverse correlation between keratoconus grade and TCT; the more advanced the disease the less the TCT value. Only in the very mild group there was no correlation between K and TCT. Conclusion The corneal asphericity and pachymetry are inversely correlated to keratometry in keratoconus patients. There is no correlation between CV and severity of keratoconus. How to cite this article Torquetti L, Ferrara G, Ferrara P. Correlation of Anterior Segment Parameters in Keratoconus Patients. Int J Kerat Ect Cor Dis 2012;1(2):87-91.

Download Full-text

Effect of Proparacaine 0.375%-Sodium Fluorescein 0.25% Eye Drop Mixture and Fluorescein Strip on Anterior Segment Parameters

Journal of Ophthalmology ◽

10.1155/2018/5926508 ◽

2018 ◽

Vol 2018 ◽

pp. 1-5

Author(s):

Mustafa Doğan ◽

Mehmet Cem Sabaner ◽

Mehmet Akif Erol

Keyword(s):

Pupil Diameter ◽

Corneal Thickness ◽

Anterior Segment ◽

Sodium Fluorescein ◽

Chamber Volume ◽

Anterior Chamber Volume ◽

Mixture Group ◽

The Mean ◽

Anterior Segment Parameters ◽

15Th Minute

Purpose. To determine the effect of proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip on anterior segment parameters commonly used in routine ophthalmology practice. Methods. 115 healthy volunteers without any systemic or ocular disease were divided into two groups. 57 volunteers were in the proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture group, and 58 volunteers were in the fluorescein strip group. Measurements (CCT (central corneal thickness), topographic pupil diameter, AD (aqueous depth), ACV (anterior chamber volume), ICA (iridocorneal angle), LLD (limbus-limbus distance), and CV (corneal volume)) were taken before and at 1, 5, 15, and 30 minutes after application. Results. 59 (51.3%) participants were female, and 56 (48.7%) were male. The mean age of the drop application group was 26.88 ± 8.03, and the mean age of the strip application group was 26.33 ± 7.28. The mean CCT was 556 ± 32 μm before drop application and 569 ± 30 μm in the 1st minute, 560 ± 32 μm in the 5th minute, and 559 ± 31 μm in the 15th minute. The change was statistically significant (p<0.001, p=0.005, and p=0.013, resp.). Before the strip application, mean CCT was 552 ± 36 μm, while it increased to 556 ± 36 μm at the 1st minute, and this change was statistically significant (p=0.002). The mean CV before dropping was 59.29 ± 3.53 mm3 and 60.62 ± 3.53 mm3 at the 1st minute and 59.66 ± 3.70 mm3 at the 5th minute, which was statistically significant (p<0.001 and p=0.034). Mean topographic pupil diameters at the 1st, 5th, 15th, and 30th minute after application of drops and strips were not significantly changed compared to the preapplication values in the AD, ACV, ICA, and LLD measurements. Conclusions. Proparacaine 0.375%-sodium fluorescein 0.25% eye drop mixture and fluorescein strip application lead to a temporary change in CCT and CV of the anterior segment parameters. Anterior segment measurements with the Scheimpflug camera have to be done before topical fluorescein application.

Download Full-text

Analysis of Anterior Segment Parameters and Wavefront Aberrations of the Myopic Eyes Using Two Scheimpflug-based Devices: The Pentacam vs Sirius

10.21203/rs.3.rs-298563/v1 ◽

2021 ◽

Author(s):

Ali Mirzajani ◽

Rasoul Amini Vishteh ◽

Rezvan Masroor

Keyword(s):

Corneal Thickness ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Corneal Surface ◽

Mean Values ◽

Wavefront Aberrations ◽

Measurement Results ◽

The Mean ◽

Anterior Segment Parameters ◽

Corneal Tomography

Abstract Purpose: To measurements, comparisons, and agreement of the anterior segment parameters and wavefront aberrations of the myopic eyes through the Pentacam and Sirius tomography systems. Methods: The Pentacam and Sirius were used to measure the corneal anterior segment tomography and wavefront aberrations of the myopic eyes with a mean age of 25.66±3.77 (range from 19 to 31 years).Various parameters such as the anterior keratometric reading of the flattest meridian K1, anterior K2, thinnest corneal thickness, corneal surface asphericity Q-value, anterior chamber depth, Root mean square (RMS) of higher-order aberrations, RMS of lower-order aberrations, and RMS of total aberrations were analyzed. Also, the agreement between the Pentacam and Sirius was assessed by calculating 95% limits of agreement and plotting the Bland–Altman graphs.Results: One eye of 99 myopic subjects (49 men, 50 women) aged 19 to 31 years was randomized and evaluated. All measured parameters of the Pentacam and Sirius tomography systems were statistically significant (p<0.001) in comparison with each other expect the mean values of K1, K2, and thinnest corneal thickness (p>0.05). The thinnest corneal thickness findings showed the poorest agreement (95 %limit of agreement from -8.71 to 24.21) and the greatest difference (mean difference: 7.75).Conclusions: The differences between the gained measurement results of the devices suggests that they should not be used interchangeably for corneal tomography imaging in clinical practice and surgery decision.

Download Full-text

Corneal Biomechanical Parameters and Central Corneal Thickness in Glaucoma Patients, Glaucoma Suspects, and a Healthy Population

Journal of Clinical Medicine ◽

10.3390/jcm10122637 ◽

2021 ◽

Vol 10 (12) ◽

pp. 2637

Author(s):

Mª. Ángeles del Buey-Sayas ◽

Elena Lanchares-Sancho ◽

Pilar Campins-Falcó ◽

María Dolores Pinazo-Durán ◽

Cristina Peris-Martínez

Keyword(s):

Central Corneal Thickness ◽

Corneal Thickness ◽

Mean Difference ◽

The Other ◽

Control Group ◽

Healthy Population ◽

Diagnostic Categories ◽

Significant Difference ◽

Biomechanical Parameters ◽

The Mean

Purpose: To evaluate and compare corneal hysteresis (CH), corneal resistance factor (CRF), and central corneal thickness (CCT), measurements were taken between a healthy population (controls), patients diagnosed with glaucoma (DG), and glaucoma suspect patients due to ocular hypertension (OHT), family history of glaucoma (FHG), or glaucoma-like optic discs (GLD). Additionally, Goldmann-correlated intraocular pressure (IOPg) and corneal-compensated IOP (IOPcc) were compared between the different groups of patients. Methods: In this prospective analytical-observational study, a total of 1065 patients (one eye of each) were recruited to undergo Ocular Response Analyzer (ORA) testing, ultrasound pachymetry, and clinical examination. Corneal biomechanical parameters (CH, CRF), CCT, IOPg, and IOPcc were measured in the control group (n = 574) and the other groups: DG (n = 147), FHG (n = 78), GLD (n = 90), and OHT (n = 176). We performed a variance analysis (ANOVA) for all the dependent variables according to the different diagnostic categories with multiple comparisons to identify the differences between the diagnostic categories, deeming p < 0.05 as statistically significant. Results: The mean CH in the DG group (9.69 mmHg) was significantly lower compared to controls (10.75 mmHg; mean difference 1.05, p < 0.001), FHG (10.70 mmHg; mean difference 1.00, p < 0.05), GLD (10.63 mmHg; mean difference 0.93, p < 0.05) and OHT (10.54 mmHg; mean difference 0.84, p < 0.05). No glaucoma suspects (FHG, GLD, OHT groups) presented significant differences between themselves and the control group (p = 1.00). No statistically significant differences were found in the mean CRF between DG (11.18 mmHg) and the control group (10.75 mmHg; mean difference 0.42, p = 0.40). The FHG and OHT groups showed significantly higher mean CRF values (12.32 and 12.41 mmHg, respectively) than the DG group (11.18 mmHg), with mean differences of 1.13 (p < 0.05) and 1.22 (p < 0.001), respectively. No statistically significant differences were found in CCT in the analysis between DG (562 μ) and the other groups (control = 556 μ, FHG = 576 μ, GLD = 569 μ, OHT = 570 μ). The means of IOPg and IOPcc values were higher in the DG patient and suspect groups than in the control group, with statistically significant differences in all groups (p < 0.001). Conclusion: This study presents corneal biomechanical values (CH, CRF), CCT, IOPg, and IOPcc for diagnosed glaucoma patients, three suspected glaucoma groups, and a healthy population, using the ORA. Mean CH values were markedly lower in the DG group (diagnosed with glaucoma damage) compared to the other groups. No significant difference was found in CCT between the DG and control groups. Unexpectedly, CRF showed higher values in all groups than in the control group, but the difference was only statistically significant in the suspect groups (FHG, GLD, and OHT), not in the DG group.

Download Full-text

Comparison of IOP Measurement by Goldmann Applanation Tonometer, ICare Rebound Tonometer, and Tono-Pen in Keratoconus Patients after MyoRing Implantation

Journal of Ophthalmology ◽

10.1155/2019/1964107 ◽

2019 ◽

Vol 2019 ◽

pp. 1-7

Author(s):

Mahmoud Rateb ◽

Mahmoud Abdel-Radi ◽

Zeiad Eldaly ◽

Mohamed Nagy Elmohamady ◽

Asaad Noor El Din

Keyword(s):

Central Corneal Thickness ◽

Pearson Correlation ◽

Corneal Thickness ◽

Altman Analysis ◽

Bland Altman Analysis ◽

Rebound Tonometer ◽

Goldmann Applanation Tonometer ◽

Significant Difference ◽

Applanation Tonometer ◽

Icare Rebound Tonometer

Purpose. To evaluate the different IOP readings by Goldmann applanation tonometer (GAT), ICare rebound tonometer, and Tono-Pen in keratoconus patients after MyoRing implantation. To assess the influence of central corneal thickness (CCT) and thinnest corneal location (TCL) on IOP measurements by different tonometers. Setting. Prospective observational study was conducted in two private centers in Egypt from February 2015 to November 2016. Methods. Seventeen eyes of 10 patients suffering from keratoconus and who underwent MyoRing implantation were recruited. All subjects underwent GAT, ICare, and Tono-Pen IOP measurements in random order. Central corneal thickness and thinnest corneal location were assessed by Pentacam. Difference in mean in IOP readings was assessed by T-test. Correlation between each pair of devices was evaluated by Pearson correlation coefficient. The Bland–Altman analysis was used to assess intertonometer agreement. Results. Seventeen eyes (10 patients) were evaluated. The mean IOP reading was 13.9 ± 3.68, 12.41 ± 2.87, and 14.29 ± 1.31 mmHg in GAT, ICare, and Tono-Pen group, respectively. There was a significant difference between IOP readings by GAT/ICare and Tono-Pen/ICare (p value: 0.032 and 0.002, respectively) with no significant difference between GAT/Tono-Pen (p value: 0.554). Mean difference in IOP measurements between GAT/ICare was 1.49 ± 2.61 mmHg, Tono-Pen/ICare was 1.89 ± 2.15 mmHg, and GAT/Tono-Pen was −0.39 ± 2.59 mmHg. There was no significant correlation between the difference in IOP readings among any pair of devices and CCC or TCL. The Bland–Altman analysis showed a reasonable agreement between any pair of tonometers.

Download Full-text

Validation of a Belgian Prediction Model for Patient Encounters at Football Mass Gatherings

Prehospital and Disaster Medicine ◽

10.1017/s1049023x21000923 ◽

2021 ◽

pp. 1-6

Author(s):

Kris Spaepen ◽

Door Lauwaert ◽

Leonard Kaufman ◽

Winne AP Haenen ◽

Ives Hubloue

Keyword(s):

Pearson Correlation ◽

First Aid ◽

Rank Test ◽

Mean Deviation ◽

Mass Gatherings ◽

Actual Patient ◽

Significant Difference ◽

Correlation Tests ◽

The Mean ◽

Patient Presentation

Abstract Background: To validate the Belgian Plan Risk Manifestations (PRIMA) model, actual patient presentation rates (PPRs) from Belgium’s largest football stadium were compared with predictions provided by existing models and the Belgian PRIMA model. Methods: Actual patient presentations gathered from 41 football games (2010-2019) played at the King Baudouin Stadium (Brussels, Belgium) were compared with predictions by existing models and the PRIMA model. All attendees who sought medical help from in-event health services (IEHS) in the stadium or called 1-1-2 within the closed perimeter around the stadium were included. Data were analyzed by ANOVA, Pearson correlation tests, and Wilcoxon singed-rank test. Results: A total of 1,630,549 people attended the matches, with 626 people needing first aid. Both the PRIMA and the Hartman model over-estimated the number of patient encounters for each occasion. The Arbon model under-estimated patient encounters for 9.75% (95% CI, 0.49-19.01) of the events. When comparing deviations in predictions between the PRIMA model to the other models, there was a significant difference in the mean deviation (Arbon: Z = −5.566, P <.001, r = −.61; Hartman: Z = −4.245, P <.001, r = .47). Conclusion: When comparing the predicted patient encounters, only the Arbon model under-predicted patient presentations, but the Hartman and the PRIMA models consistently over-predicted. Because of continuous over-prediction, the PRIMA model showed significant differences in mean deviation of predicted PPR. The results of this study suggest that the PRIMA model can be used during planning for domestic and international football matches played at the King Baudouin Stadium, but more data and further research are needed.

Download Full-text

A Comparative Study Between Preoperative Subconjunctival Bevacizumab Injection And Postoperative Topical Application In Prevention Of Recurrence After Excision Of Primary Pterygium In Egyptian Patients

QJM ◽

10.1093/qjmed/hcab109.004 ◽

2021 ◽

Vol 114 (Supplement_1) ◽

Author(s):

Basma Helal Mohamed ◽

Othman Ali Othman Ziko ◽

Hisham M Khairy Abd El Dayem ◽

Nancy Ezzelregal Khamis Ahmed

Keyword(s):

Corneal Thickness ◽

Anterior Segment ◽

P Value ◽

Eye Drops ◽

Subconjunctival Injection ◽

Fibrovascular Tissue ◽

Significant Difference ◽

Group 2 ◽

Group 1 ◽

Primary Pterygium

Abstract Purpose to compare between recurrence incidence after primary pterygium excision when using preoperative subconjunctival injection of Bevacizumab (Avastin) and using it as a postoperative eye drops. Methods thirty two eyes of thirty patients (two patients had bilateral pterygium) with primary pterygia were clinically examined, classified into 3 groups and operated by simple excision with bare sclera technique. Group 1 included 10 patients received Bevacizumab (Avastin) in the form of eye drops (10 mg/ml) 3 times daily for 6 days postoperative. Group 2 included 10 patients received preoperative Bevacizumab in the form of subconjunctival injection (1.25 mg/0.05ml) single dose 1 week preoperative. Group 3 included 10 patients (12 eyes) 2 patients with bilateral Pterygium didn’t receive any form of Bevacizumab. Postoperative follow up was done clinically and by serial photography at 1 week, 1 month, 3 months and 6 months searching for signs of recurrence and/or complications. Results The results showed different grades of recurrence in 18 eyes of 32.True recurrence was seen in 7 patients of 18 (1 patient in group 1, 2 in group 2 and 4 in group3).Recurrence grades in group 1and 2 who used the Bevacizumab (20%grade II, 50% grade III, and 30% grade IV). Recurrence could be predicted by 100% depending on fibrovascular tissue appearing in the surgical bed at 3 months postoperative (P value 0.038).Preoperative fleshy pterygium has high statistical significance in realation to recurrence(P value = 0.006).Patient’s sex, residence and occupation had no statistically significant value in the process of recurrence (P value > 0.05). Patients with recurrent Pterygia (in group 1&2) had statistically significant changes in the corneal K- readings at 3 months and 6 months.No significant difference in the limbal or central corneal thickness in the operated eye and the other eye (Pvalue > 0.05). Conclusion Bevacizumab (Avastin) is a well tolerated drug with multiple drug delivery methods.The eye drops give better results than the subconjunctival injection.Appearance of fibrovascular tissue in the surgical bed at 3 months predict the recurrence by 100%. Preoperative fleshy pterygia will mostly recur again whatever Bevacizumab form was used .The corneal thickness by anterior segment OCT has no role in prediction or detection of early pterygium recurrence.

Download Full-text

Usefulness of the Non-Contact Tonometry in Out-Patient Screening

Asian Journal of Ophthalmology ◽

10.35119/asjoo.v15i2.232 ◽

2016 ◽

Vol 15 (2) ◽

Author(s):

Satheesh Solomon T Selvin ◽

Chris Elsa Samson Jacob ◽

Thomas Kuriakose

Keyword(s):

Central Corneal Thickness ◽

Care Center ◽

Corneal Thickness ◽

Tertiary Care ◽

Cross Sectional Study ◽

Applanation Tonometry ◽

Cross Sectional ◽

Significant Difference ◽

Iop Measurement ◽

The Mean

Purpose: Goldmann applanation tonometry (GAT) is considered the gold standard for Intraocular Pressure (IOP) measurement. It has the disadvantages of being a contact device, need for a slit-lamp, non-portability and need of a skilled examiner. Many hospitals are using a Non Contact Tonometry (NCT) as a screening device to save clinician time, however the usefulness is not proved in terms of reliability. This study was aimed to determine the usefulness of the Air-puff tonometer (TONOREF NIDEK II, NIDEK CO., LTD., JAPAN) over a GAT in a tertiary care center. Design: Cross-sectional Study Methods: This was a cross-sectional, non interventional observational study conducted on 224 eyes (right eye) from 224 patients. All patients underwent the IOP measurement with both methods and a central corneal thickness (CCT) measured. The data was analyzed using SPSS 20.0 software. Results: The mean age of the patients was 40.3±11.29 years. There was a statistically significant difference (p<0.001) between the mean NCT and GAT readings which persisted even after correction for central corneal thickness. The correlation between NCT and GAT using Pearson’s correlation coefficient was strong irrespective of the corrections for their corneal thickness (r = 0.751 and 0.718 for uncorrected and corrected values respectively). The correlation of the individual clinicians for the readings varied from moderate to strong. The ROC curve showed the best sensitivity and specificity to occur at around 13 to 14 mmHg. Conclusion: NCT seems to overestimate the IOP at low ranges as compared to the GAT and underestimate at higher ranges. The crossover of the values is seen between 12 to 13 mmHg. The clinician should do an individualized analysis of his/her GAT measurements to the readings of the NCT machine at the clinic to obtain clinician specific nomogram.

Download Full-text

Anatomical and Visual Effects of Implantable Phakic Contact Lens on Correction of Myopia

10.21203/rs.3.rs-1245764/v1 ◽

2022 ◽

Author(s):

Mahmoud Ekram ◽

Ahmed Mohamed Kamal Elshafei ◽

Asmaa Anwar Mohamed ◽

Mohamed Farouk Sayed Othman Abdelkader

Keyword(s):

Visual Acuity ◽

Anterior Chamber ◽

Contact Lens ◽

Anterior Segment ◽

Anterior Chamber Depth ◽

Case Series ◽

Care Group ◽

Case Series Study ◽

Significant Difference ◽

The Mean

Abstract Purpose: To evaluate the anatomical effects of implantable phakic contact lens (IPCL) (Care Group, India) on anterior segment and its visual outcomes .Patients and methods: In a prospective interventional case series study, 60 highly myopic eyes of 32 patients were subjected to IPCL implantation in the Ophthalmology Department of Minia University Hospital, Egypt from January 2019 to June 2021. All patients had complete ophthalmic examination and were followed up for 1 year. Pentacam was used for preoperative and postoperative estimation of anterior chamber depth (ACD), anterior chamber angle (ACA), anterior chamber volume (ACV) and IPCL vault in the 1st, 3rd, and 12th months. Assessment of corneal endothelium was done using specular microscope preoperatively and after 12 months. Preoperative and postoperative refraction and visual acuity were measured. Results: There was a statistically significant decrease in ACD, ACA, and ACV. There was no significant difference between preoperative and postoperative mean intraocular pressure (IOP) by the 12th month (P=0.163). The mean preoperative endothelial cell count (ECD) was significantly reduced from 2929.3±248 cells/mm2 to 2737.9±303 cells/mm2 at the 12th month (P<0.001). with a statistically highly significant improvement of mean Log Mar uncorrected visual acuity (UCVA) from 1.48±0.19 preoperatively to 0.46±0.11 by the end of follow up (P<0.001) with insignificant difference between preoperative best corrected visual acuity (BCVA) and postoperative UCVA (P=0.209). In the 12th month, the mean vault was 240±540 μm. No sight threatening complications occurred.Conclusion: Although IPCL induced anatomical changes, it was safe and effective for correction of high myopia.

Download Full-text

The pattern of central corneal thickness in patients attending a Tertiary Hospital in Dar-Es-Salaam

World Journal of Advanced Research and Reviews ◽

10.30574/wjarr.2021.9.2.0056 ◽

2021 ◽

Vol 9 (2) ◽

pp. 127-133

Author(s):

Annamary Stanislaus ◽

Ntsilane Susan Mosenene ◽

Celina Mhina ◽

John Stanslaus Kisimbi ◽

Frederick Robert Burgess ◽

...

Keyword(s):

Central Corneal Thickness ◽

Corneal Thickness ◽

Dar Es Salaam ◽

Applanation Tonometry ◽

P Value ◽

Muhimbili National Hospital ◽

National Hospital ◽

Cross Sectional ◽

Significant Difference ◽

The Mean

Background: Central Corneal Thickness (CCT) is an indicator of corneal health status as well as being an essential tool in assessment and management of corneal diseases. It is an important factor in the diagnosis and management of glaucoma as it affects the measurement of intraocular pressure. However, the pattern of central corneal thickness in our population is not known. Our study aimed to describe the CCT measurements and their variation with age and sex among patients attending the eye clinic at Muhimbili National Hospital (MNH), in Dar es Salaam, Tanzania. Methodology: A hospital-based descriptive, cross-sectional study used convenient sampling to recruit adult patients aged 18 years and above, presenting to the MNH between August 2016 and January 2017.Visual acuity assessment, Goldman applanation tonometry and CCT assessment using an ultrasound pachymeter were performed. Patients with previous intraocular surgery were excluded. Results: A total of 398 patients (208 males and 190 females) were recruited. The mean CCT was 526.64±38.30 µm; being 523.99±38.20 µm for males and 529.7±38.3 µm for females. 226 (56.85%) had CCT of less than 520 µm.There was no statistically significant difference in CCT between gender. The proportion of patients with thinner CCT increased with increasing age from 25.8% in those < 30 years to 75% in those aged 71years and above. The mean CCT decreased with increasing age with P-value<0.001. Conclusion: The average CCT in patients attending Muhimbili National Hospital is 526.64 µm (SD 38.30) which is generally thin, inversely proportion to age and similar that of other Africans and African-Americans. This finding has implications for the management of glaucoma in this population.

Download Full-text

Correlation between Central Corneal Thickness and Degree of Myopia among Malaysian Patients Undergoing Laser Keratorefractive Surgery

Journal of Advances in Medicine and Medical Research ◽

10.9734/jammr/2020/v32i2230705 ◽

2020 ◽

pp. 52-58

Author(s):

Sagili Chandrasekhara Reddy ◽

Mohd Mansor Shariff ◽

Aina Malindri Dasrilsyah

Keyword(s):

Optical Coherence Tomography ◽

Refractive Surgery ◽

Central Corneal Thickness ◽

Corneal Thickness ◽

Anterior Segment ◽

Military Hospital ◽

Moderate Degree ◽

Optical Coherence ◽

Corneal Refractive Surgery ◽

The Mean

Purpose: To determine the central corneal thickness in myopic adult patients scheduled for laser corneal refractive surgery and to explore its correlation with degree of refractive error. Materials and Methods: The case records of 130 myopic patients who underwent laser corneal refractive surgery in a military hospital over a period of two years were reviewed to determine the central corneal thickness. All patients had 6/6 vision with best correction, and did not have any other anterior segment or fundus diseases in both eyes. The central corneal thickness was measured with Visante Carl Zeiss anterior segment optical coherence tomography instrument. Results: Out of 130 patients, males were more (73, 56.2%); mean age of patients was 33.8 years (range 18-60 years) and majority were Malays (110, 84.6%). The spherical power of myopia ranged from – 0.5 to – 10.00 D, and the cylindrical power ranged from – 0.25 to – 3.25 D. The mean central corneal thickness of both eyes was 528.2 µm (range 331- 615 µm); in the mild degree of myopia (- 0.50 to - 2.00 D) 527.9 µm, moderate degree (- 2.25 to -5.00 D) 529.4 µm, and high degree (-5.25 to -11.00 D) 523.9 µm. Conclusion: The anterior segment optical coherence tomography provides noncontact, rapid, pachymetry mapping of the corneal thickness. In Malaysian patients, the mean central corneal thickness of both eyes in myopia was 528.1 µm (range 331- 615 µm). There was no correlation between the mean central corneal thickness and degree of myopia, different genders, age groups, ethnic groups and two eyes.

Download Full-text