Central Corneal Thickness Values Research Articles

Comparison of topical 5% NaCl versus 10% Mannitol for the treatment of corneal edema after phacoemulsification.

This study aimed to compare the efficacy of topical 5% Sodium Chloride (NaCl) and 10% Mannitol agents in managing corneal edema following uncomplicated cataract surgery. Patients with postoperative corneal edema were enrolled, and they were divided into three groups for comparison. Anterior chamber depth (ACD), axial length (AL), intraocular lens (IOL) power, cumulative dissipated energy (CDE), best-corrected visual acuity (BCVA), central corneal thickness (CCT), and endothelial cell count (ECC) were assessed among the groups. Fifty-eight eyes of 58 patients were included. The study comprised the NaCl group (using topical 5% NaCl, n = 21), Mannitol group (using topical 10% Mannitol, n = 17), and a control group without osmotic agent use (n = 20). Age, gender, ACD, AL, IOL power, and CDE were similar across groups. Postoperative day-1 CCT values showed no significant difference between groups. Additionally, at postoperative 1 week, CCT values were [663.4 ± 100.2] microns in the NaCl group, [640.4 ± 68.9] microns in the Mannitol group, and [760.3 ± 76.7] microns in the Control group. Although CCT and BCVA values were better in the Mannitol group at postoperative 1 week, no statistically significant difference was found between the groups at 1 week and 1 month postoperatively. Furthermore, corneal edema positively correlated with CDE and negatively correlated with AL. Topical 5% NaCl and 10% Mannitol agents are effective and reliable agents that showed faster recovery of corneal edema during the early postoperative period after uncomplicated cataract surgery. The choice between these agents may depend on factors such as patient tolerability, cost, and availability.

Comparison of automated corneal endothelial cell analysis in healthy and postoperative eyes with phakic intraocular lens: a cross-sectional study and literature review

PurposeMeasurement of corneal endothelial cells is critical for postoperative evaluation of phakic intraocular lens (pIOL) surgery. However, inter-instrument differences in corneal endothelial cell density (ECD) after pIOL implantation have not yet been reported. This study aimed to compare automated corneal endothelial cell analysis between CellChek-20 (Konan Medical, Hyogo, Japan) and EM-4000 (Tomey, Nagoya, Japan) in healthy and postoperative eyes with pIOL.MethodsWe retrospectively analyzed 154 healthy and 236 postoperative eyes after pIOL surgery. Endothelial cell measurements were performed using CellChek-20 and EM-4000 with autofocusing and automated image analysis. ECD, percentage of hexagonal cells (HEX), coefficient of variation in cell size (CoV), and central corneal thickness (CCT) were compared between the two devices.ResultsThe ECDs of the two devices were highly correlated in both healthy (Spearman’s correlation coefficient [r] = 0.805; p < 0.001) and postoperative (r = 0.901; p < 0.001) groups. ECD from CellChek-20 was higher than EM-4000 in both healthy (mean difference = 228.9 cells/mm2; p < 0.001) and postoperative (mean difference = 115.6 cells/mm2; p < 0.001) groups. The CCT values also showed a strong correlation in healthy eyes (r = 0.974; p < 0.001) and in postoperative eyes (r = 0.936; p < 0.001); however, significant inter-instrument differences were observed. HEX and CV showed significant differences and relatively weak correlations (r < 0.7) between the two devices in both healthy and postoperative groups.ConclusionThe ECD values between the two instruments were correlated, but that of the CellChek-20 was significantly higher than that of the EM-4000 in both healthy and postoperative eyes after pIOL surgery. Most previous studies have also shown that the Konan software overestimated the ECD compared to other products in automatic measurement mode. The possibility of measurement bias should be considered when replacing equipment used for corneal endothelial cell measurements.

Comparison of intraocular pressure measurements with the tono-pen, goldmann applanation tonometer, and noncontact tonometer in nonglaucomatous pseudophakic children.

To evaluate the agreement between the Goldman applanation tonometer (GAT), Tono-Pen, and noncontact tonometer (NCT) in the measurement of intraocular pressure (IOP) in pseudophakic children. The medical records of nonglaucomatous pseudophakic children between 2009 and 2019 were retrospectively analyzed. A total of 46 eyes of 23 patients operated for bilateral pediatric cataract were included in the study. The patients' mean age was 13.4 ± 4.1years. Central corneal thickness (CCT) and IOP values measured with the GAT, Tono-Pen, and NCT were recorded. Agreement between the tonometers was evaluated by intraclass correlation coefficients (ICC) and the Bland-Altman method. The mean IOP of the 46 eyes included in the study was measured as 13.7 ± 2.3mm Hg with the GAT, 16.0 ± 2.3mm Hg with NCT, and 16.5 ± 2.3mm Hg with the Tono-Pen (p < 0.001). There is no statistical difference between NCT and Tono-Pen measurements, while GAT measurements were significantly lower than those of the NCT and Tono-pen. ICC values showed fair agreement between NCT and Tono-Pen (ICC = 0.720), whereas there was poor agreement between GAT and NCT (ICC = 0.501) and Tono-pen (ICC = 0.314). With all devices included in the study, thicker corneas were associated with higher IOP measurements. Although there was moderate agreement between the NCT and Tono-Pen, there was a statistically significant difference in the IOP values provided by the three devices. Our results suggest these devices should not be used interchangeably.

Anterior scleral thickness in Marfan syndrome: A quantitative analysis.

To investigate the anterior scleral thickness (AST) in patients with Marfan syndrome (MFS). A prospective, cross-sectional study was conducted at the Department of Ophthalmology, Ghent University Hospital, Ghent, including patients with a genetically confirmed clinical diagnosis of MFS and age-, gender- and axial length-matched controls. Subjects with known corneal, conjunctival or scleral pathology and a history of ocular surgery, including pars plana vitrectomy, recent contact lens use or high-grade astigmatism were excluded. Subjects underwent non-cycloplegic autorefraction, Scheimpflug-based corneal tomography, axial length measurement and spectral-domain optical coherence tomography (OCT). AST was manually measured at 1 mm (AST1), 2 mm (AST2) and 3 mm (AST3) from the scleral spur, temporally and nasally. A total of 56 subjects (28 subjects in the MFS group and 28 matched subjects in the control group) were included in this study. In patients with MFS, AST was significantly reduced compared to matched controls, both overall and at every analysed measuring point in the nasal and temporal areas (p < 0.001). Central corneal thickness (CCT) and mean keratometry (Kmean) values were significantly lower in patients with MFS (p < 0.05). A positive correlation was found between nasal AST and CCT in patients with MFS. No correlation was found between AST and Kmean or between AST and axial length. In patients with MFS with ectopia lentis, compared to those without, temporal AST3 was significantly lower (p < 0.05). AST was significantly lower in patients with MFS harbouring a variant predicted to cause haploinsufficiency compared to those with a variant expected to lead to a dominant negative effect for both nasal and temporal measurements. Based on anterior segment OCT measurements, AST of patients with MFS is significantly lower compared to matched controls.

Comparison of Scheimpflug Corneal Tomography and Anterior Segment Optical Coherence Tomography Measurements in Corneal Cystinosis: A Case Series.

To report the clinical course and compare the utility of Scheimpflug tomography (ST) and anterior segment optical coherence tomography (AS-OCT) for central corneal thickness (CCT) and corneal densitometry (CD) assessment in patients with corneal crystals owing to nephropathic cystinosis. A retrospective chart analysis of three patients with nephropathic cystinosis and the presence of corneal cystine crystals in both eyes was performed. All patients underwent clinical examination and anterior segment photography, ST, and AS-OCT scans. Corneal densitometry was exported from built-in proprietary software for ST and from custom-made validated software for AS-OCT. Anterior segment optical coherence tomography images were rescaled to grayscale units from 0 (maximum transparency) to 100 (minimum transparency) to match built-in ST densitometry readings. Furthermore, the mean pixel intensity, representative of CD, was calculated from the pixels corresponding to the segmented cornea. All three patients had pathognomonic cystine crystals deposits in the cornea and were treated with cysteamine medications that resulted in clinical improvement. The CCT measured using ST exhibited a range from 560 to 958 μm. Conversely, when assessed with AS-OCT, the CCT varied within the range of 548 to 610 μm. Both examinations could be performed, but in the more severe cases, AS-OCT showed far greater utility to estimate CD. In four of six eyes examined, ST showed disproportionate CCT values, compared with the AS-OCT, whereas reliable CD measurements were only available in AS-OCT. The AS-OCT could be considered a baseline ocular measurement in cystinosis and in the evaluation of disease progression and treatment efficacy.

Correlation between HbA1C and CCT in T2DM

Abstract An observational cohort study of central corneal thickness (CCT) in type 2 diabetes mellitus (T2DM) patients in hyperglycemic and euglycemic states. Context: To assess the significance of glycemic control in CCT measurement. Aims: The main aim was to assess the change in CCT with the change in glycemic state by following them after 3 months. Settings and Design: This study was carried out in the department of ophthalmology, SMVMCH, Pondicherry. Materials and Methods: This is an observational cohort study carried out at Sri Manakula Vinayagar Medical College and Hospital after obtaining ethics committee clearance. Fifty-six T2DM patients with HbA1C &gt;7 were included in this study with informed consent. Clinical history with complete ophthalmic examination done, CCT was measured using ultrasonic pachymetry (UP) along with blood samples to measure their blood sugars and HbA1C values. They were advised to follow up on the treatment given by the medical department. Patients were reviewed after 3 months to measure the CCT and blood sugar values. Statistical Analysis: Done using STATA software 16.0. Continuous data and categorical data were assessed using paired t-test and Chi-square test, respectively. Normality of data using Shapiro–Wilk normality test. Statistical significance was adopted with P &lt; 0.05. Results: In our study, the initial mean HbA1C was 9.4 ± 1.9 and mean CCT was 552.6 ± 40.6 μm, whereas follow-up mean HbA1C was 7.1 ± 1.2 and mean CCT was 548.5 ± 38 μm which shows statistical significance. Conclusion: Diabetics present with thicker corneas and there is a decrease in thickness once glycemic control has been achieved. Keeping this in mind, we suggest assessment of CCT in all diabetic patients during clinical work-up.

A comparative study of central corneal thickness in patients with diabetes and without diabetes mellitus

Diabetes mellitus (DM) is becoming increasingly and seriously prevalent lifestyle health problem worldwide. Up to 70% of diabetic patients can develop corneal changes and are also difficult to manage. Several studies were done to find out the morphological changes in cornea in type 2 DM, but the results are highly variable. Central corneal thickness (CCT) is widely considered as a constant parameter, so are measured only once during follow up in our daily clinical practice. Here we study the effect of diabetes over CCT, for a better understanding of the impact of diabetes over CCT.A comparative observational study of one and half years done among 106 diabetes and 106 non diabetic patients between 35 to 75 years old, attending ophthalmology OPD. CCT of both eyes was measured and mean CCT and was compared between diabetic and non-diabetic groups, among different subgroups of diabetic subjects and other parameters.CCT was thicker among diabetic groups (553.4434um) than non-diabetic groups (549.8491) but was not statistically significant according to our study. But there was statistically significant (p value 0.000165) thickening with increasing grades of diabetic retinopathy (DR) (mild DR (535.4524), moderate DR (543) and PDR (591.5)). Our study concludes that DM is associated with thicker cornea; hence CCT values can vary with time in DM. So repeated CCT measurements for corrected IOP values is advised and warranted in DM patients for proper management of IOP.

Do intravitreal anti-VEGF injections have an effect on corneal endothelial remodeling in children with premature retinopathy?

This study was carried out to investigate the effects of retinopathy of prematurity (ROP) and intravitreal antivascular endothelial growth factor (VEGF) injections on the corneal endothelium in the childhood period of patients who have had ROP. The material of comparative case-control clinical study consisted of patients followed up with ROP between February 2013 and February 2023. The eyes in the study group were divided into two subgroups consisting of those who received intravitreal anti-VEGF injections (subgroup 1) and those who were followed up only (subgroup 2). Central corneal endothelial cell density (ECD), coefficient of variation (CV), central corneal thickness (CCT), and pleomorphism parameters in the childhood period were evaluated by corneal specular microscopy and compared with age-matched healthy control subjects. There were 84 eyes of 42 patients with ROP in the study group and 80 eyes of 40 healthy children in the control group. Mean CCT was significantly higher in subgroup 1 and the control group than in subgroup 2 (p = 0.037), and mean ECD was significantly higher in subgroup 2 than in subgroup 1 and the control group (p < 0.001). There was no significant difference between subgroup 1 and the control group in mean ECD and CCT values (p = 1.000 for both cases). Considering that ROP patients who received intravitreal anti-VEGF injections had more advanced-stage ROP than ROP patients who were followed up only, these findings suggest that intravitreal anti-VEGF applications in ROP cases may lead to corneal endothelial parameters similar to those of healthy eyes.

Changes in endothelial cell density after conventional phacoemulsification and FLACS in eyes with dense cataracts.

To compare the safety, effectiveness, and changes in endothelial cell density (ECD) after standard phacoemulsification and femtosecond laser-assisted cataract surgery (FLACS) in dense cataracts (Lens Opacities Classification System III grade 3.0 NO and above). Nethradhama Superspeciality Eye Hospital, Bangalore, India. Prospective, randomized, comparative study. 100 eyes of 100 patients were randomly assigned to either conventional phacoemulsification surgery (CPS) or FLACS (LENSAR Laser System) using predefined patterns of nuclear fragmentations. Measured outcomes included intraoperative phacoemulsification time, irrigation fluid volume, surgical time, and complication rates. ECD was evaluated at baseline, 2 weeks, and 6 months postoperatively. The CPS group had significantly higher mean total phacoemulsification time (11.17 ± 6.5 seconds vs 8.03 ± 3.77 seconds), effective phacoemulsification time (6.14 ± 3.62 seconds vs 4.42 ± 2.07 seconds), and total surgical time (8.18 ± 2.36 minutes vs 7.11 ± 1.55 minutes) than the FLACS group ( P < .001). Volume of irrigation fluid was comparable between the 2 groups (CPS, 36.7 ± 12.18 mL; FLACS, 38.64 ± 13.73 mL ( P = .45). Mean corneal edema score and central corneal thickness values on postoperative day 1 were significantly higher for the CPS group. At 6 months, % ECD loss was significantly higher in the CPS group (16.08%) vs the FLACS group (12.8%) ( P < .001). 3 eyes in the CPS group had wound burns of varying severity. FLACS with customized nuclear fragmentation patterns resulted in significantly less intraoperative phacoemulsification time, surgical time, and endothelial cell loss compared with conventional phacoemulsification when treating dense cataracts. CTRI/2021/12/038887.

Intraocular pressure and central corneal thickness in a healthy student population

Introduction/Objective. Intraocular pressure is an important parameter of eye health, especially when glaucoma is suspected. So far, few studies have been published that aimed to determine the average value of intraocular pressure and central corneal thickness in a healthy population aged 20?30 years. The aim of this study was to determine the distribution of the values of intraocular pressure and central corneal thickness in healthy student population. Methods. In a cross-sectional study, intraocular pressure and central corneal thickness were measured on a sample of a healthy population, aged 22?37 years. Intraocular pressure was measured using the Goldmann applanation tonometry method, while central corneal thickness was measured using ultrasound pachymetry. The analysis of numerical values was done using the methods of descriptive statistics. Results. By measuring intraocular pressure and central corneal thickness in 641 subjects (1282 eyes), the average value of intraocular pressure was determined to be 14.79 ? 2.31 mmHg, and central corneal thickness was 553.92 ? 25.56 ?m. By comparing two groups of subjects, one male group and the other one female, we determined that there was no statistically significant difference in the average value of intraocular pressure (t-test, p &gt; 0.05), and the average value of central corneal thickness (t-test, p &gt; 0.05) between the sexes. Conclusion. The determined average value of intraocular pressure and central corneal thickness is similar to those determined in other cross-sectional studies of this type. No statistically significant difference was found in the intraocular pressure values and the central thickness of the cornea by sex.

The association of pre-photorefractive keratectomy Schirmer-1 test value with postoperative corneal epithelial thickness, ocular surface discomfort, and visual acuity.

To investigate the association of pre-photorefractive keratectomy Schirmer-1 test value with post-photorefractive keratectomy central corneal epithelial thickness, ocular surface disease index score, and uncorrected distance visual acuity. Patients were categorized according to preoperative Schirmer-1 value: the normal Schirmer Group (n=54; Schirmer-1 test value, >10 mm) and the low Schirmer Group (n=52; Schirmer-1 test value, between 6 and 10 mm). We analyzed ablation depth, visual acuity, result of Schirmer-1 test (with anesthesia), tear film break-up time, ocular surface disease index score, central corneal epithelial thickness, and spherical equivalent refraction. We found significant differences between the groups in Schirmer-1 test value, tear film break-up time, and ocular surface disease index score, both preoperatively and postoperatively (p<0.001). The preoperative central corneal epithelial thicknesses of the two groups were similar (p>0.05). After photorefractive keratectomy, the Schirmer-1 test value and spherical equivalent refraction decreased in both groups (p<0.05), and ocular surface disease index scores and central corneal epithelial thickness values increased in the low Schirmer Group (p<0.001) but not in the normal Schirmer Group (p>0.05). The postoperative central corneal epithelial thicknesses of the low Schirmer Group were significantly higher than those of the normal Schirmer Group (p<0.001). Postoperative uncorrected distance visual acuity did not differ significantly between the two groups (p>0.05). In patients with low Schirmer-1 test values before photorefractive keratectomy, the corneal epithelium thickened and ocular surface complaints increased during the postoperative period. However, changes in the corneal epithelium did not affect the postoperative uncorrected distance visual acuity. To reduce postoperative problems on the ocular surface in these patients, we recommend that dry eye be treated before photorefractive keratectomy.

Changes in Central Corneal Thickness and Central Macular Thickness following Uncomplicated Small-incision Cataract Surgery.

Cataract surgery is an invasive procedure that causes mechanical and inflammatory insult to the eye. The objective was to study the changes in central corneal thickness (CCT) which is an indirect indicator of corneal endothelial dysfunction and the changes in macular thickness following uncomplicated small incision cataract surgery (SICS) Materials and methods: This was a prospective observational study with a before-and-after design conducted in Reiyukai Eiko Masunaga eye hospital, Banepa, Kavrepalanchok, Nepal. SICS was performed on 68 eyes of 62 patients. Change in CCT and central macular thickness (CMT) from baseline was observed post-surgery on the first day, one week, and six weeks. There were 27 (43.5%) females and 35 males (56.5%) in the study. Mean age was 58.26 ±10 years. This difference of visual acuity between pre and post-operative state was statistically significant. The first post-operative day (POD) and first week post-operative CCT values when compared with preoperative CCT values were statistically significant. However, post-operative CCT values at six weeks were similar to preoperative values. Also, the differences at day one, first week and six weeks post-operative CMT values when compared with preoperative CMT values were statistically significant. This study revealed that there is a significant rise in CCT after SICS which gradually tends to normalize at six weeks. Similarly there is a gradual rise in CMT after SICS persisting even at six weeks. These changes were subtle and there was a marked improvement of visual acuity at six weeks after SICS.

COVID-19 related changes in corneal curvature and endothelium after mild infection

PurposeTo investigate subclinical corneal changes using corneal topography in the evaluation of corneal curvature and specular microscopy in the evaluation of the endothelial layer after mild coronavirus disease 2019 (COVID-19). MethodsIn this prospective study, 112 eyes of 56 individuals with mild COVID-19 who recovered were investigated. Mean cell density (CD), mean coefficient of variation (CV), mean percentage of hexagonal cells, mean cell area (AVG), and central corneal thickness (CCT) were recorded from specular microscopy. K readings, including simulated keratometry flat (K1), simulated keratometry steep (K2), average keratometry (Kmean) and maximum keratometry (Kmax), pachymetric measurement and central corneal thickness (CCT), corneal volume (CV), topographic astigmatism (TA), curvature asymmetry front (CAf) and curvature asymmetry back (CAb) were recorded from corneal topography. Best corrected visual acuity (BCVA), spherical equivalant and biometric measurements were recorded. ResultsThe mean time interval between examinations before and after COVID-19 infection was approximately one year. Analysis of specular microscopy data showed a statistically significant change in all endothelial cell parameters (p<0.001) except the cell count (p = 0.358). The median (range) endothelial cell density (ECD) value was significantly lower after COVID-19 at 2356 (2289–2400) than before, when it was 2596 (2545–2640). Furthermore, CCT values showed a significant increase (p<0.001). The topographic values including K2, Kmax and TA and biometric measurements did not change. The Spherical Equivalant (SE) values showed significant myopic progression after COVID-19 (p<0.001). ConclusionEndothelial parameters changed more than the changes in corneal curvature and ocular biometric measurements after mild COVID-19. The decrease in endothelial cell number and hexagonality and increase in polymorphism after COVID-19 were striking.

Repeatability and agreement of AOCT-1000 M, RTVue XR and IOL master 500 in measuring corneal thickness mapping and axial length applying principle of optical coherence tomography

PurposeTo evaluate the repeatability and agreement of Fourier-domain optical coherence tomography (AOCT-1000 M and RTVue XR) and partial coherence interferometry biometer (IOL Master 500) in measuring corneal thickness mapping and axial length respectively.MethodsCorneal thickness was measured by AOCT-1000 M and RTVue XR. Axial lengths were measured by AOCT-1000 M and IOL Master 500. The repeatability and agreement of corneal thickness and axial length were calculated in two groups of devices. The intraclass correlation coefficient (ICC) was used to verify the repeatability of the device. The 95% confidence interval of the difference compared to the set cut-off value was used to verify the agreement between the two devices.ResultsA total of 60 subjects with 58 eyes were included. The central corneal thickness measured by AOCT-1000 M and RTVue XR were 504.46 ± 42.53 μm and 504.43 ± 42.89 μm respectively. The average difference between groups was 0.03 ± 4.58 μm, and the 95% confidence interval was (-1.17, 1.24), which was far less than the set threshold value of 15 μm (P < 0.001). Both RTVue XR and AOCT-1000 M had very good ICC values of central corneal thickness (0.998 and 0.994, respectively). The average axial lengths measured by AOCT-1000 M and IOL Master 500 were 24.28 ± 1.25 mm and 24.29 ± 1.26 mm respectively and the 95% confidence interval was (-0.02, 0.01), which was less than the set threshold value of 0.15 mm (P < 0.001). The ICC for both devices were 1.000.ConclusionGood repeatability and agreement were seen in measurements of central corneal thickness and axial length by AOCT-1000 M.

Corneal Clarity after Phacoemulsification: Nuclear Management by Stop and Chop Method

Introduction: Restoration of effective vision is the principal aim of all modalities of cataract surgery including phacoemulsification. In this method, nuclear part of the cataractous lens is emulsified by ultrasonic power. Energy level of ultrasonic power and turbulence of fluid in the anterior chamber play an important role in corneal endothelial cell loss which inturn influences post-operative corneal clarity. Endothelial cell loss can be minimized by modification of nuclear management method. The common nuclear division techniques of phacoemulsification are stop and chop, divide and conquer and phaco chop. Purpose: To show post-operative corneal clarity after phacoemulsification by stop and chop technique of nuclear divisions. Materials and Methods: This prospective observational study was conducted at selected outdoor patients from January, 2023 to June, 2023 over 33 patients of age related cataract selected for phacoemulsification surgery. Patients were selected based on specific selection criteria. Selected patient underwent detail, ocular and systemic examinations as well as relevant investigations which included assessment of corneal endothelial cell count and central corneal thickness. Phacoemulsification were done in all patients by a single expert surgeon where technique of nuclear management by stop and chop were chosen randomly. Patients were followed up on 1 week, 4 weak and 12 weak after surgery. Corneal endothelial cell count and central corneal thickness were assessed in each visit. All the relevant data were presented by appropriate tables. Results: The mean age of the study subjects were 60.96 with standard deviation 1.75 years out of which 14 were males and 17 were females. Pre-operative value of mean endothelial cell count was 2620+-70.20/mm2. Mean value of endothelial count was 2420+-68.90/ mm2, 2345+-66.64/ mm2, 2310+-66.04/ mm2 respectively after 1 week , 4 weeks and 12 weeks after surgery. Mean value of central corneal thickness was 545+-40.50 micrometer, 535+-40.02 micrometer, 532+-39.85 micrometer respectively after 1 week, 4 weeks and 12 weeks after surgery. Conclusion: Quantitative assessment of endothelial cell count and central corneal thickness shows that at end of the study there was no significant difference in mean endothelial cell count and mean central corneal thickness . Medicine Today 2023 Vol.35(2): 118-120

Evaluation of the structural changes of uveitis patients by optical biometry.

Objective (Aim): To observe the ocular structural changes in active and inactive uveitis patients. Methods: This retrospective study involved 30 patients (32 eyes) with anterior and intermediate uveitis cases and 54 eyes of 54 cases in a control group, who were admitted to the Ophthalmology Department at Trakya University. In the study group, 14 patients were females, 16 patients were males and in the control group 26 volunteers were females, and 28 volunteers were male of the 54 volunteers. Anterior chamber depth, axial length, intraocular pressure, lens thickness, central corneal thickness, steep and flat values in keratometry, corrected visual acuity in both eyes, anterior chamber cells, and vitreous cells were measured and compared between three groups (two uveitis groups - active and inactive - and control group). Results: In the comparison of the median values of axial length, central corneal thickness, and steep and flat values of keratometry, the values of the patients with active uveitis were higher than the ones in the control group in each parameter, but no significant difference was observed. The anterior chamber depth parameter value was higher, the lens thickness value was lower in patients with active uveitis than the values in the control group and the differences were statistically significant (p<0,05). No significant structural differences in the values of the active and inactive group patients (p>0,05) were observed. Conclusions: Only lens thickness and anterior chamber depth parameters were statistically significant in patients with active uveitis, compared with the inactive uveitis group. Anterior chamber depth measurement values were higher and lens thickness measurement values were lower in patients with active uveitis when compared with the control group. Abbreviations: AAU = Acute anterior uveitis, CAU = Chronic Anterior Uveitis, AC = Anterior Chamber, IOP = Intraocular Pressure, IVCM = in vivo Confocal Microscopy, AS-OCT = Anterior Segment Optical Coherence Tomography, UBM = Ultrasound Biomicroscopy, LFP = Laser Flare Photometry, KP = Keratic Precipitates, OCT = Optical Coherence Tomography, AL = Axial Length, ACD = Anterior Chamber Depth, LT = Lens Thickness, CCT = Central Corneal Thickness, Ks = Steep Value of Keratometry, Kf = Flat Value of Keratometry, AUP = Active Uveitis Patients, IUP = Inactive Uveitis Patients, SUN = Standardization of Uveitis Nomenclature.

Central Corneal Thickness and Intraocular Pressure in Children with Type I Diabetes Mellitus.

The aim of this study is to determine the mean central corneal thickness (CCT) and mean intraocular pressure (IOP) in children with type 1 diabetes mellitus (T1DM) and to determine the relationship between CCT and IOP on the one hand and age, gender, retinopathy hemoglobin A1c (HbA1c), and duration of diabetes on the other. This is a case-control, hospital-based study conducted at Hospital ___________ between January and November 2022. Thirty-eight children with T1DM were recruited as cases, and 38 healthy children were recruited as controls. The cases and controls then underwent ophthalmic examination, IOP measurement, and CCT measurement using optical coherence tomography (OCT) of the right eye. The IOP measurements were adjusted for CCT for further analysis. The means CCT and IOP values were significantly higher in the T1DM group than in the control group (p-value<0.02 respectively). The mean CCT was 542.18 ± 20.40 µm in the T1DM group, and 529.52 ± 26.17 µm in the control group. The mean IOP was 14.68 ± 1.98 mmHg in the T1DM group, and 13.52 ± 1.66 mmHg in the control group. The mean HbA1c was 10.68 ± 2.49% in the T1DM group. Age and duration of diabetes mellitus (DM) were found to have a significant association with CCT in children with T1DM. The duration of DM was also found to be significantly associated with the IOP. Gender and HbA1c levels were found to have no significant relationship with either CCT or IOP. Children with T1DM have significantly higher CCT and IOP than the average child. The duration of DM is a significant factor that impacts both CCT and IOP. In addition, age is another factor that affects CCT in children with T1DM.

Klinik olarak Tek Taraflı Psödoeksfoliasyon Sendromu Olanların Ön Segment Parametrelerinin Schempflug Görüntüleme Tekniği ile değerlendirilmesi

Objective: We aimed to compare the intraocular pressure (IOP), keratometry values (K), and anterior segment parameters of patients with clinically unilateral pseudoexfoliation syndrome (PEX) with the other eyes without PEX and the control group. Material and Method: Fifty four patients with unilateral PEX findings and 40 participants without PEX findings in both eyes were included in the study as a control group. IOP was measured by Goldmann applanation tonometry. K values and anterior segment parameters [central corneal thickness (CCT), anterior chamber depth (ACD), iridocorneal angle (ICA), and anterior chamber volume (ACV)] were measured using Scheimpflug imaging technique. Results: The mean age of PEX patients was 67.9±9.2 years, while the mean age of the control group was 58.9±5.7 years. The IOP values of the eyes with PEX were significantly higher than the other eyes (p=0.02), and there was no significant difference between them and the control group (p=0.59). In terms of K values and anterior segment parameters, the measurements of eyes with PEX and the other eyes, and eyes with PEX and control group were similar (p&amp;gt;0.05). Conclusion: In our study, eyes with PEX had higher IOP values than the fellow eyes and control group. In addition, thinner CCT, narrower ACD, and ICA values were found in eyes with PEX than in the other eyes. However, these values were not statistically significant.

Evaluation of Corneal Topography Changes Following Deep Anterior Lamellar Keratoplasty in Patients with Keratoconus

Background. The aim of this study is to evaluate the morphologic changes of the cornea and anterior chamber by using corneal topography (CT) in patients undergoing deep anterior lamellar keratoplasty (DALK) due to keratoconus. Patients and methods. This observational case-control study included total 53 eyes of 53 patients with keratoconus and underwent DALK surgery. All patients were evaluated preoperatively and 3 months after suture removal with CT. In CT, anterior chamber depth (ACD), iridocorneal angle (ICA), anterior chamber volume (ACV), central corneal thickness (CCT), maximum keratometric value (Kmax), flattest simulated meridian keratometry (SimK1), steepest simulated meridian keratometry (SimK2) and simulated keratometry average (SimKavg) results were compared before and after DALK surgery. Results. A significant increase was observed in CCT values after DALK surgery (p &lt; 0.001). Patients showed statistically significant decrease in Kmax, SimK1, SimK2 and SimKavg values (p &lt; 0.001 for all). Postoperative ACD and ACV values were significantly lower (p &lt; 0.001). The ICA values showed no significant difference (p = 0.183) between preoperative and postoperative values (49,95 ± 5,85 and 46,30 ± 11,33 respectively). Conclusion. We determined a dramatic decrease in keratometric values, ACD and ACV values and an increase of corneal thickness after DALK surgery. Although DALK can be performed without interfering with the anterior chamber, has a significant effect in anterior chamber.

Comparison Between Ocular Biometric Parameters and Intraocular Pressure With and Without Contact Lenses.

To compare the values of central corneal thickness, anterior chamber depth (ACD), lens thickness (LT), vitreous length (VL), axial length (AL), and corneal-compensated intraocular pressure performed with and without contact lenses (CL). Forty volunteer participants (16 men and 24 women, 24.2±2.9 years) were recruited. In a single visit, participants underwent autorefraction, keratometry, biometry, topography, pachymetry, and tonometry with the naked eye (without CL). Then, biometry, pachymetry, and tonometry were repeated twice wearing two CL (somofilcon A and nesofilcon A) fitted in a random order. Many of the ocular biometric values were affected by the use of CL during measurements (paired t test; all P ≤0.003), except for LT and VL (Wilcoxon test; both P ≥0.272). Corneal-compensated intraocular pressure was also affected by contact lens wear during measurements, obtaining lower values when wearing them (Wilcoxon test; all P ≤0.001). Central corneal thickness, ACD, AL, and corneal-compensated intraocular pressure measurements cannot be performed while wearing CL. However, LT and VL measurements were not affected by any contact lens use. In addition, it was observed that ACD results from both devices are not interchangeable either when measured with the naked eye or using any contact lens.