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Purpose: To compare readings of intraocular pressure (IOP) taken with the Goldmann applanation tonometer (GAT), the non?contact tonometer (NCT), and the rebound tonometer (RBT), and to compare their correlation with central corneal thickness (CCT). Methods: This was a prospective, cross?sectional, observational study to which patients above 18 years of age were enrolled. A total of 400 eyes of 200 non?glaucomatous patients underwent IOP recordings using the GAT, NCT, and RBT, and CCT was also noted. Informed consent of the patients was taken. The IOP readings taken via the three methods were compared and correlated with CCT. Paired t test was used to compare the two devices. Simple and multivariate linear regression analyses were used to study the relationship between factors. A P value less than 0.05 was considered significant. Correlation was determined using the Pearson correlation coefficient, and a Bland–Altman graph was plotted. Results: Mean IOP measured by the NCT was 15.65 ± 2.80 mmHg, by the RBT was 14.23 ± 3.05 mmHg, and by the GAT was 14.69 ± 2.97 mmHg. The mean CCT was 510.61 ± 33.83 microns. The difference between mean IOP recorded by the NCT and that by the RBT was 1.41 ± 2.39 mmHg, between the NCT and GAT was 0.95 ± 2.03 mmHg, and between the GAT and RBT was 0.45 ± 2.22 mmHg. The difference between the IOP values was statistically significant (P < 0.005). All tonometers showed a statistically significant correlation with CCT, but it was observed that the NCT had a stronger correlation (0.4037). Conclusion: The IOP readings taken by all the three methods were comparable; however, RBT values were closer to GAT values. CCT did influence the IOP values, and this should be kept in mind while evaluating.
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Objective:To investigate the distribution of intraocular pressure (IOP) in high-altitude population aged 18 years and over in Xining, Qinghai and establish the reference interval (RI) of IOP.Methods:A cross-sectional study was conducted in Xining, Qinghai Province at 2.271 km above sea level from September 2019 to May 2020.Ophthalmic examinations and IOP measurement were conducted among subjects from Physical Examination Center of Qinghai Provincial People's Hospital.The subjects who had been living in Xining without leaving for three months were enrolled.Ophthalmic examinations included vision examination, IOP measurement, slit-lamp microscopy, fundus photography, anterior and posterior segment optical coherence tomography.IOP was measured using Goldmann applanation tonometry under local anesthesia.Subjects with factors that could cause significant changes in IOP and affect the accuracy of IOP measurement, and those who were unable to receive IOP measurement were excluded.Subjects were grouped according to sex, age and ethnicity, and the distribution and RI of IOP were compared among all groups.This study adhered to the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of Beijing Tongren Hospital, Capital Medical University (No.TRECKY2017-024). Written informed consent was obtained from each subject.Results:A total of 6 120 subjects (6 120 eyes) aged 18-90 years old were enrolled, including 2 850 males and 3 270 females with average age of (45.54±13.85) years.The average IOP of high-altitude population in Xining, Qinghai Province was (14.32±1.93) mmHg (1 mmHg=0.133 kPa), with the RI of 10.54-18.10 mmHg.The average IOP was (14.42±1.98) mmHg in male with the RI of 10.54-18.30 mmHg, (14.23±1.88) mmHg in female with the RI of 10.55-17.91 mmHg.The IOP of male was higher than that of female ( t=3.71, P<0.001). The IOP of Han, Tibetan, Hui and other nationalities were (14.38±1.91), (13.93±2.06), (14.21±1.87), (13.94±1.95) mmHg, respectively, with a statistically significant overall difference ( F=6.73, P<0.001). The IOP of Han nationality was significantly higher than that of Tibetan, Hui and other nationalities, and the differences were statistically significant (all at P<0.05). Conclusions:RI of IOP in high-altitude population from Xining, Qinghai is lower compared with normal altitude area.
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@#Introduction: Glaucoma causes a reduction of contrast sensitivity (CS) while thinner central corneal thickness is (CCT) associated with the risk of glaucoma. Thus, in glaucoma suspect patients, CS and CCT measurements may better evaluate and monitor the disease. The purpose of this study was to compare CS and CCT between a Primary Open Angle Glaucoma (POAG) suspect group and a normal group of similar age. Methods: CS was measured with the Pelli-Robson CS chart, while CCT was measured with a hand-held pachymeter. In total, 115 glaucoma suspects and 102 normal participants were included. Results: There was a significant effect of the clinical condition on CS [F(1,209)=5.409, p=0.02]. The effect of age on CS was also significant [F(3,209)=20.419, p<0.001]. The interaction between age and clinical condition was not statistically significant [F(3,209)=0.815, p=0.49]. CS of POAG suspects was significantly lower than that of the normal group for the younger age groups (40 to 59 years old) but not for the older age groups (50 to 80 years old). There was no significant effect of clinical condition on CCT [F(3,209)=0.754, p=0.39]. However, there was a significant effect of age on CCT [F(3,209)=3.789, p=0.01]. Conclusion: Contrast sensitivity measurement is potentially useful to be integrated with routine investigations for POAG suspect patients, especially those who are younger than 60 years old. Measurements of central corneal thickness alone may not be able to differentiate between POAG suspects and visually normal individuals.
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Purpose: To evaluate and compare endothelial cell changes in phacoemulsification and manual small- incision cataract surgery (MSICS) in patients with uncomplicated senile cataracts. Methods: This was a prospective, tertiary care hospital-based, randomized, double-blinded interventional study. In total, 152 patients with an uncomplicated senile cataract of nuclear grade III and above were recruited. Exclusion criteria included patients with preoperative endothelial cell density (ECD) less than 1500 cells/mm3, a history of previous ocular surgery, any other coexisting ocular disease, and intraoperative or postoperative surgical complications. Preoperative and postoperative values of ECD and central corneal thickness (CCT) were measured, analyzed, and correlated with various factors. Results: Patients were randomized into two interventional groups-MSICS and phacoemulsification. Factors associated with significant drop in postoperative ECD following phacoemulsification were patients with advanced age (P = 0.01), higher grades of cataract (P = 0.01), and longer effective phacoemulsification time (P = 0.007). Shallow anterior chamber depth (ACD) was strongly associated with greater ECD loss in both groups (P < 0.0001). A threshold value of 2.86 mm of ACD was defined for minimal endothelial cell loss following phacoemulsification. CCT was observed to slightly increase postoperatively in both groups but was insignificant (P > 0.05). Conclusion: Both MSICS and phacoemulsification have similar postoperative visual outcomes. An increase in postoperative CCT is insignificant following surgery. Greater postoperative ECD loss is associated with phacoemulsification with advanced age, hard nuclear cataracts, and longer effective phacoemulsification time. ACD can be used as an essential parameter preoperatively to determine the choice of surgical technique between MSICS and phacoemulsification
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Purpose: To study corneal endothelial changes post phacoemulsification in diabetic and non?diabetic patients. Methods: A comparative, prospective, observational study was conducted on 100 diabetic and 100 non?diabetics who underwent phacoemulsification. All patients were operated by the same surgeon by using the phaco chop technique to exclude any surgeon?related bias. Endothelial cell count, CCT, and coefficient of variance (CV) were measured with a specular microscope along with BCVA preoperatively and at 1 week, 4 weeks, and 3 months postoperatively. For statistical analysis, data were analyzed by using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA). Data were summarized as mean and standard deviation for numerical variables and count and percentages for categorical variables. Chi square test, independent sample T test, and paired T test were used to compare the data. P ? 0.05 was considered statistically significant. Results: Postoperatively at 1 week, 4?week, and 3 months follow?up intervals, the mean endothelial cell count and coefficient of variance were significantly higher, and the mean percentage of hexagonal cells was significantly lower in non diabetic as compared to the diabetic group. A significant difference in mean central corneal thickness of the two groups was observed at 1?week and 4?weeks postoperative intervals; at both these intervals, the mean value was significantly higher in non diabetic as compared to the non?diabetic group. However, at 3?months post?operative interval, the difference between the two groups was not significant statistically. Mean BCVA values were significantly higher in diabetic as compared to the diabetic group at all three follow?up intervals. Conclusion: The findings of the present study show that endothelial cell characteristics are adversely affected in diabetic eyes as compared to non?diabetic patients undergoing phacoemulsification; this might also have an effect on the visual outcomes.
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Background:Corneal endothelial cells are susceptible to mechanical trauma from ultrasound energy during phacoemulsification. Several studies have reported various results of phacoemulsification effect on corneal endothelial cells between diabetic and non-diabetic patients due to stressful events. Present study was aimed to evaluate corneal endothelial density, hexagonality and Central Corneal Thickness (CCT) changes between diabetic and non-diabetic patients at early postoperative period and 1 month after phacoemulsification.Material And Methods:Specular microscopy examinations prior to phacoemulsification and at early postoperative period and 1 months after phacoemulsification were performed on diabetic and non-diabetic groups in grade 2 and grade 3 nuclear sclerosis. Laterthe changes in endothelial density, the percentage of hexagonality, and Central corneal thickness were evaluated.Result:Mean age of 120 study sample was 58.45 years (standard deviation –8.498 years), with the highest 74 years and lowest 43 years. Therewere 53 (44%) females and 67 (56%) males in the study. 42 (35%) samples were from 51-60 years age group followed by 37 (30.83%) subjects in 61-70 years age group. Mean corneal endothelial cell density decreases after cataract surgery in comparison with pre-operative density among study samples. Mean pre-operative corneal endothelial cell density was lower in diabetics in comparison with non-diabetics, and the difference was statistically significant. Cell density count decreases after cataract surgery inboth groups with significant difference between two groups. Mean corneal endothelial cell morphology (hexagonal cell percentage) decreases after cataract surgery in comparison with pre-operative density among study sample s. Central corneal thickness increases in early postoperative period followed by normalisation at day 30.Conclusion:Diabetic group showed greater hexagonality decrease compared to non-diabetic group at 1 month after phacoemulsification. It is suggested that diabetic corneal endothelium requires additional care and protective measures during cataract surgery to minimize surgical trauma. There were no statistically significant differences in the endothelial loss and Central corneal thickness changes between the diabetic and non-diabetic group at 1 month follow up after phacoemulsification.
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It is essential to assess the corneal thickness in diabetes patient.Introduction: diabetes mellitus is a major cause of blindness throughout the worldDiabetic retinopathy is the most importance given on day to day basics studies especially for ophthalmologist studied indicators in eye. However, functional oddities have been recognised in cornea too like changes in central corneal thickness.Objectives: 1. To estimate the central corneal thickness (CCT) of type 2 diabetes mellitus patients without diabetic retinopathy age/sex matched normal people. 2. To measure central corneal thickness (CCT) of type 2 diabetes mellitus patient with diabetic retinopathy with age/ sex matched normal person.Methods: This is a hospital based case control study.Expected Results: The central corneal thickness is more in type 2 diabetes patients than non-diabetic individual.
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Introducción: La longitud axial ocular, la profundidad de la cámara anterior y el grosor corneal central, son tres índices biométricos oculares importantes. Estas medidas son útiles para mostrar los cambios en la población vietnamita con presbicia. Objetivos: Determinar los índices biométricos oculares, longitud axial ocular, profundidad de la cámara anterior y espesor corneal central, en población vietnamita y evaluar la correlación entre ellos y con la edad y el sexo. Métodos: Se realizó un estudio transversal en población vietnamita, con edad de 46 a 65 años. Se recogieron los datos de longitud axial ocular, profundidad de la cámara anterior y grosor corneal central. Se utilizaron la prueba t de Student y ANOVA para comparar las medias de los índices, agrupados por edad y sexo. La relación entre los índices biométricos oculares fue probada mediante la correlación de Pearson, con un nivel de significación de p < 0,05. Resultados: Se analizaron 390 ojos de 195 personas. La longitud media del eje ocular fue 23,13 ± 0,66 mm, la profundidad de la cámara anterior, 3,15 ± 0,36 mm, el grosor corneal central, 529,15 ± 30,57 µm. Los tres índices biométricos disminuyeron con la edad y fueron mayores en los hombres (p < 0,05). La longitud del eje ocular tuvo relación positiva con la profundidad de la cámara anterior (r = 0,411 y p < 0,001) y el espesor corneal central (r = 0,141 y p < 0,001). No hubo relación entre la profundidad de la cámara anterior y el grosor corneal central (r = 0,039 y p = 0,44). Conclusión: Los tres índices biométricos oculares disminuyeron con la edad y fueron mayores en los hombres. La longitud del eje ocular se relacionó con la profundidad de la cámara anterior y el grosor de la córnea central(AU)
Introduction: Ocular axial length, anterior chamber depth and central corneal thickness are three important ocular biometric indices. These measurements are useful to show changes in the Vietnamese population with presbyopia. Objectives: To determine the ocular biometric indices, ocular axial length, anterior chamber depth and central corneal thickness, in Vietnamese population and evaluate the correlation between these indices. Methods: A cross-sectional study was carried out in a Vietnamese population, aged 46 to 65 years. Data on ocular axial length, anterior chamber depth and central corneal thickness were collected. The Student's t test and ANOVA were used to compare the means of the indices, grouped by age and sex. The relationship between the ocular biometric indices was tested using Pearson's correlation, with a significance level of p <0.05. Results: 390 eyes of 195 people were analyzed. The mean length of the ocular axis was 23.13 ± 0.66 mm, the depth of the anterior chamber, 3.15 ± 0.36 mm, and the central corneal thickness, 529.15 ± 30.57 µm. The three biometric indices decreased with age and were higher in men (p <0.05). The length of the ocular axis had a positive relationship with the depth of the anterior chamber (r = 0.411 and p <0.001) and the central corneal thickness (r = 0.141 and p <0.001). There was no relationship between anterior chamber depth and central corneal thickness (r = 0.039 and p = 0.44). Conclusion: Three ocular biometric indices decreased with age and were higher in men. The length of the ocular axis was related to the depth of the anterior chamber and the thickness of the central cornea(AU)
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Humans , Middle Aged , Axial Length, Eye/physiology , Anterior Chamber/physiology , Cross-Sectional Studies , Biometry/methodsABSTRACT
@#AIM: To investigate the changes of corneal endothelial cells and ocular surface after phacoemulsification for age-related cataract(ARC)patients with diabetes mellitus. <p>METHODS: Retrospective case study. A total of 190 cataract patients with diabetes mellitus who received phacoemulsification combined with IOL implantation in 190 eyes admitted to our hospital from January 2017 to January 2019 were selected. In addition, 230 ARC patients without diabetes who underwent phacoemulsification and intraocular lens implantation at the same time were selected as the control group. Ocular surface disease index(OSDI)score, tear film rupture time(BUT), basal tear secretion test(S I t), corneal endothelial cell density and coefficient of variation were compared between the two groups.<p>RESULTS: There was no significant difference in preoperative OSDI score, BUT, S I t, corneal endothelial cell density and coefficient of variation between the two groups(<i>P</i>>0.05). In the observation group, OSDI scores were significantly increased 1wk, 1mo and 3mo after surgery compared with those before surgery, with statistically significant differences(all <i>P</i><0.01). The OSDI scores of patients in the control group increased significantly one week and one month after the operation compared with those before the operation, with statistically significant differences(all <i>P</i><0.01). The OSDI scores in the observation group at each time point after the operation were higher than those in the control group, with statistically significant differences(all <i>P</i><0.05). One week after surgery, 1mo after surgery, BUT and S I t in the two groups decreased significantly compared with that before surgery(<i>P</i><0.05), and the difference was not statistically significant compared with that before surgery 3mo after surgery. In addition, compared with BUT between the two groups, the observation group had a lower tear film stabilization time and a more significant decrease(<i>P</i><0.05). The corneal endothelial cell density in the two groups decreased significantly 1wk, 1mo and 3mo after surgery compared with that before surgery(<i>P</i><0.05). The variation coefficient of corneal endothelial cells in the two groups was statistically significant 1wk after the operation and 1mo after the operation compared with that before the treatment(<i>P</i><0.05). The variation coefficient of corneal endothelial cells in the observation group was more significant than that in the control group(<i>P</i><0.05).<p>CONCLUSION: Cataract patients with diabetes surgery tolerance is low, the corneal endothelial cell density and the central corneal thickness and corneal appears before tear secretion with stability and foundation treatment have significant changes, and its characteristic is cataract patients without diabetes more apparent, clinical intraoperative and postoperative corneal endothelial protection should be strengthened, and the surface of the eye protection ability of the organization.
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@#AIM: To determine the ocular biometric measurements and central corneal thickness(CCT)in Nigerian children so as to have a reference database.<p>METHODS:A hospital-based observational study of a cross-section of children seen consecutively between November 2017 and January 2018. The socio-demographic data of patients, visual acuity(VA)was assessed with LogMAR charts and Lea charts according to age group. Examination under anesthesia(EUA)was carried out for children eight years and below. Anterior and posterior segments examination through dilated pupil were done. Corneal diameters(CD)were assessed using calipers. Intraocular pressures(IOP)were examined using hand held tonometer, CCT and axial length(AL)were measured using the ultrasonic pachymeter. Cycloplegic refraction was carried out after clinical examination. Data were entered into and analysed using SPSS version 17 to generate results through descriptive statistics. Frequencies and cross tabulations of variables were done(<i>P</i><0.05).<p>RESULTS:Sixty-six children with 132 eyes, of ages between 3-16(mean: 9.13±3.70)years were studied. Male with female ratio was 1:1.7. The modal age group range was 6-10 years(42.4%). Most of them were primary school students 36(54.5%). The predominant parents' occupation was traders/unskilled workers(51.6%)and the professionals/civil servants(30.3%). The mean right and left VA were 0.45±0.46 and 0.45±0.44(LogMAR)respectively. The mean right and left horizontal corneal diameters(HCD)were 10.5±1.6 mm and 10.37±1.45 mm respectively. The mean right and left vertical corneal diameters(VCD)were 9.7±1.2 mm and 9.7±1.3 mm respectively. The mean right and left CCT were 556.71±2.61 μm and 556.47±45.53 μm respectively. Myopia 23(34.8%), myopic astigmatism 18(27.3%)and simple astigmatism 16(24.2%)were the commonest types refractive error. No significant associations were observed between CCT and HCD(<i>P</i>=0.739), VA(<i>P</i>=0.058)and refractive error(<i>P</i>=0.199). However, CCT slightly significantly correlated with the age groups(<i>P</i>=0.055).<p>CONCLUSION: Mean values for CCT, IOP and CD are known for the first time in Nigerian children. No significant association was seen between CCT and VA, CD and refractive errors. Further studies are required to ascertain findings.
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Objective:To explore the differences of anterior segment parameters in Uyghur patients with pseudoexfoliation syndrome (PEX), pseudoexfoliation glaucoma (PEXG), primary open-angle glaucoma (POAG) and age-related cataracts in Xinjiang.Methods:A retrospective study was conducted, Uyghur patients included 114 eyes of 84 cases with PEX, 96 eyes of 70 cases with PEXG, 88 eyes of 72 cases with POAG and 80 eyes of 80 cases with age-related cataracts (control, CON) who had received treatment in Ophthalmology Center of Xinjiang Military Region General Hospital of Chinese People's Liberation Army from April 2019 to July 2020 were selected to obtained central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), axial length (AL) and corneal curvature (horizontal curvature K1 and vertical curvature K2).Results:There was no significant difference in gender ratio and age of patients between CON, PEX, PEXG and POAG groups ( P > 0.05). The CCT of patients in CON, PEX, PEXG and POAG groups were (545.52 ± 34.22), (536.81 ± 42.64), (516.74 ± 32.39) and (530.38 ± 28.72) μm, respectively, the CCT in CON, PEX and POAG groups were all higher than those in PEXG group ( P < 0.05), and the CCT in PEXG group became thinner. The ACD of patients in CON, PEX, PEXG and POAG groups were (3.05 ± 0.38), (2.87 ± 0.36), (2.77 ± 0.41), (2.81 ± 0.32) mm, respectively, compared with CON group, the ACD in PEX, PEXG and POAG groups were all lower ( P < 0.05). There was no significant difference in LT, AL, K1 and K2 of patients between each group ( P > 0.05). Conclusion:This study has showed that the ACD of Uyghur patients with PEX in Xinjiang is shallower than that of CON group, but the CCT of PEXG patients is thinner than that of PEX patients.
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The main attributes of cornea which makes it optically important is its ability to maintain its dehydrated state. This corneal dehydration can be achieved and maintained by various factors among which corneal endothelial cell count and morphology play a significant role. Corneal attributes considered in this study i.e. the corneal endothelial cell count and central corneal thickness are extremely variable, and changes are seen even with smaller changes in anterior segment or overall structural changes in eyes. We wanted to compare central corneal thickness in emmetropia and axial myopia and compare corneal endothelial cell count in emmetropia and axial myopia. METHODSThe sample size was decided taking into consideration various prevalence studies. The patients were consecutively recruited for the study considering the inclusion and exclusion criteria. The subjects were divided into two groups emmetropia and axial myopia and were differentiated on the basis of the axial lengths. Specular microscopy was performed for the subjects and corneal endothelial cell count, morphology and central corneal thickness were measured, and comparative study was performed. RESULTSThis study of 80 eyes shows us that the difference between mean the corneal endothelial cell count between emmetrope (2812.80 cells / mm2) and axial myopes (2653 cells / mm2) is statistically significant where p was < 0.05 while the mean central corneal thickness measurements didn’t show statistically significant change between emmetrope (490.05 microns) and axial myope. (489.37 microns). CONCLUSIONSAxial length has an indirect correlation with the corneal endothelial cell count which is statistically significant. While significant correlation between the central corneal thickness and axial length cannot be established in this study.
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Background and Objectives: The normal Central corneal thickness (CCT) ranges about 510-520 microns. It is normally seen in clinical practice that corneas which are thicker are linked with greater intraocular pressures (IOPs). The purpose of the study was to determine the central corneal thickness and establish its relationship with age and serum electrolytes in hypertensive and non-hypertensive patients. Methodology: A total of 108 subjects were included in our cross-sectional comparative study (54 hypertensive and 54 non-hypertensive). Written informed consent was taken. We measured blood pressure with mercuric sphygmomanometer. Ultrasound pachymeter was used to measure central corneal thickness while we drew 5 ml of blood for estimation of the serum electrolytes. Data was entered and evaluated using IBM SPSS 17. Quantitative variables were presented as Mean ± SD. Pearson correlation was used to find correlation of normally distributed variables p-value ≤ 0.05 was considered to be statistically significant. Results: Central corneal thickness was statistically same in hypertensive and non-hypertensive subjects. Serum Na+ was significantly increased in hypertensive subjects while serum K+ and Cl- were significantly decreased in hypertensive subjects. No significant correlation was seen in hypertensive while weak negative correlation was observed between CCT and age in non-hypertensive patients. Weak positive correlation was observed between CCT and Na+ both in hypertensive and non-hypertensive. Significant correlation was observed in CCT and K+ in hypertensive while negative correlation was seen in non-hypertensive. Weak correlation was observed in CCT and Cl- both in hypertensive and non-hypertensive. Conclusion: Mean CCT was significantly lower in hypertension. CCT and age showed weak and positive correlation in hypertensive while weak and negative correlation in non-hypertensive. Serum electrolytes and CCT showed no significant correlation.
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Purpose: To compare corrected intraocular pressure (IOP) by tonopachy with that of Goldmann applanation tonometry (GAT) in normal and glaucomatous patients. Methods: In this cross-sectional study, IOP and central corneal thickness (CCT) were measured in 426 eyes (213 normal eyes and 213 glaucomatous eyes) of 426 patients by tonopachy followed by GAT and ultrasound pachymetry. IOP was corrected for CCT by in-built formula in tonopachy and Ehlers correction factor for Goldmann tonometer. Limits of agreements were assessed using Bland朅ltman plots. Intraclass correlation coefficient was calculated to estimate the absolute agreement between single and average measurements of IOP and CCT of tonopachy with that of Goldmann tonometer and ultrasound pachymetry respectively. Results: Mean corrected IOP measured with tonopachy and GAT in glaucomatous eyes was 17.63 � 5.04 mmHg and 19.42 � 5.83 mmHg, and in controls it was 13.4 � 2.5 mmHg and 16.2 � 3.1 mmHg, respectively. Limits of agreement ranged from �63 to +9.25 mmHg for total population (mean = 2.31), �01 to +9.59 mmHg (mean = 1.79) for glaucoma group and �99 to +8.65 mmHg (mean = 2.83) for controls. Intraclass correlation coefficient for IOP measurement between tonopachy and Goldmann tonometer was 0.84 for total population, 0.85 for glaucoma group, and 0.63 for controls, respectively. Conclusion: Corrected IOP obtained by tonopachy showed moderate agreement with GAT and it is more in glaucoma patients than controls. Thus, tonopachy can be used as a screening tool, but cannot replace GAT.
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Purpose: Glaucoma is the leading cause of irreversible blindness in the world. The current study aims to estimate prevalence, features, and associations of open angle glaucoma (OAG) in a rural and urban East Indian population. Methods: This is a population based cross sectional study with two arms, rural (28 contiguous villages from 13 Gram Panchayats in Balagarh Police Station, Hooghly district) and urban (Kolkata). Individuals residing in the study area aged 40 years and above were included using multistage random cluster sampling. All subjects underwent a detailed ophthalmic examination at our base hospitals including applanation tonometry, ultrasound pachymetry, gonioscopy, and frequency doubling technology perimetry. The primary outcome was the prevalence of POAG (95% CI). Age and gender specific prevalence estimates were calculated. Multiple logistic regressions were used to analyze the risk factors. Results: Data from 7128 and 6964 subjects aged 40 years or older from Kolkata city and Hooghly district, respectively were analyzed. In the urban population, 2.10% (95% CI: 1.99–2.21%) had POAG and 0.15% (95% CI: 0.13–0.17%) had secondary OAG. In the rural population, 1.45% (95% CI: 0.59–2.31%) had POAG and 0.10 ± 0.03% (95% CI: 0.07–0.13%) had secondary OAG. Conclusion: The study concludes that higher age, higher vertical cup disc ratio (VCDR), and lower central corneal thickness (CCT) are important independent predictors of OAG and emphasizes that increased intraocular pressure (IOP) is not POAG. Gonioscopy, disc evaluation, and screening perimetry need to be incorporated in the detection protocol for glaucoma if we intend to lighten the burden of blindness due to glaucoma.
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@#AIM: To study the reliability of Pentacam, OCT, Tomey OA-2000, IOL Master700, and A ultrasound pachymetry in the measurement of central corneal thickness(CCT)in myopic eyes. <p>METHODS: CCTs of 56 myopic patients(112 eyes)were measured using Pentacam, RTVue OCT, Tomey OA-2000, IOL Master 700, and A ultrasound pachymetry(NIDEK US-500). The difference, correlation, and consistency were statistically analyzed using average values taken from the five devices and the measured values produced by each device. <p>RESULTS: CCTs of 112 eyes were determined using Pentacam(530.17±25.08)μm, OCT(519.79±26.90)μm, Tomey OA-2000(521.75±26.51)μm, IOL Master 700(519.53±28.15)μm, and A ultrasound pachymetry(542.23±26.88)μm. The average value across all five devices was 526.69±26.08μm. The results of root mean square error(RMSE)and theil inequality coefficient(TIC)showed that the degree of deviation from the average of the values measured using Pentacam was the smallest. The other four devices were, from least deviation to most, Tomey OA-2000, OCT, IOL Master 700, and A ultrasound pachymetry. Typical correlation analysis showed that the correlation coefficients between the measured values of Pentacam, OCT, Tomey OA-2000, IOL Master 700, and A ultrasound pachymetry and the average values were <i>ρ</i>=0.957, <i>P</i>=0.950, <i>P</i>=0.953, <i>P</i>=0.930, and <i>ρ</i>=0.949, respectively. The results of correlation coefficient showed that Pentacam and Tomey OA-2000 had the closest correlation with the average value. The other three were, in order of closest to furthest correlation, OCT, A ultrasound pachymetry and IOL master 700. The results also showed that the measurements of Pentacam and Tomey OA-2000 were more reliable, which was consistent with the clinical situation. The results of Bland-Altman analysis showed that the five groups of measurements were closely consistent with the average values, and the CCT measurements of Pentacam and Tomey OA-2000 were the most consistent with the average values.<p>CONCLUSION: Among the five instruments, Pentacam and Tomey OA-2000 produced results that were closest to the average value in CCT measurement, with the best correlation and consistency. Their measurement methods are more objective and safer than A-scan, so they may provide better reference data for clinical practice.
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Purpose: Pseudoexfoliation syndrome (PXS) is an age related microfibrillopathy characterized by deposition of whitish flaky material over various ocular tissues. PXS eyes are known to have thinner corneas and thus can lead to an underestimation in intraocular pressure measurement. The purpose of this study was to find if there is any variation in central corneal thickness and intraocular pressure in PXS eyes and if there was any relationship between them. Methods: A prospective observational study was done on 141 eyes of 85 patients with PXS without glaucoma between November 2015 to April 2017 in the department of Ophthalmology in a tertiary hospital. CCT and IOP were measured by a handheld ultrasonic pachymeter (DGH Technology INC. Pachette 2, USA) and Goldmann applanation tonometer respectively at 4 different times during office hours. Results: A significant reduction of about 10 ?m in mean CCT and 1.4 mmHg in mean IOP was noted over the 4 sessions which was statistically significant (P < 0.001). A significant correlation exists between IOP and CCT in PXS eyes at all times during the day (P < 0.001). Conclusion: The CCT measurements show significant thinning throughout the day, similar drop in IOP was also noted. Our study shows that there is a significant correlation between diurnal variation of CCT and IOP. Hence, it is prudent to measure CCT along with IOP at all times.
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The objective of the study is to assess the central corneal thickness (CCT) among type 2 diabetes mellitus patients and to correlate the central corneal thickness with duration of diabetes, HbA1c and severity of diabetic retinopathy. Methods: A hospital based descriptive study was conducted in Govt Medical College Kannur, Pariyaram, from April 2017 to March 2018.CCT of known diabetic patients was correlated with duration of diabetes, HbA1c and severity of retinopathy. Results: The mean central corneal thickness in diabetic patient was 550.1± 35.0µm with a range between 364 and 665 µm. Correlation of duration of diabetes and severity of diabetic retinopathy were not statistically significant. The CCT was thicker in patients with HbA1c more than 7% than HbA1c less than7% (p=0.005) which was statistically significant. Conclusion: We found that higher HBA1c level may be a marker for predicting the increase in CCT in patients with type II diabetes.
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Background: Brimonidine is a potent ocular hypotensive agent widely used in glaucoma treatment. A reduction in central corneal thickness can lead to an underestimation of intraocular pressure by Goldmann applanation tonometry and vice versa. The aim of this study is to determine whether brimonidine has an effect on central corneal thickness.Methods: 30 eyes of patients who attended the Ophthalmology OPD between the time period October 2017 and June 2018 who were newly diagnosed with normal tension glaucoma with no history of any systemic illness or not on any medication were included. Each patient underwent a complete ophthalmic evaluation including fundus examination, visual field assessment, intraocular pressure, central corneal thickness measurement by pachymetry before as well as 1 month and 6 months after starting treatment with 0.2% topical brimonidine twice daily.Results: Administration of brimonidine 0.2% resulted in an increase in central corneal thickness from 525±21 µm before starting brimonidine to 528±21 µm (p<0.05) after 1 month and 535±20 µm (p<0.001) after 6 months. It also resulted in a reduction in intraocular pressure from an initial value of 16±2 mmHg before starting brimonidine to 14±2 mmHg (p<0.05) and 13±2 mmHg (p<0.05), 1month and 6 months after starting treatment, respectively.Conclusions: The data presented in this study show that topical administration of 0.2% brimonidine twice daily results in a significant increase in central corneal thickness in patients with normal tension glaucoma.
ABSTRACT
Central corneal thickness (CCT) is an essential tool in the assessment and management of corneal disease. CCT has thus become very important for the interpretation of intraocular pressure and prerefractive procedure assessment; however little is known about its distribution within a population with wide range of refractive errors. Therefore the objective is to study the correlation of CCT with a broad range of refractive errors in rural population of Haryana. Methods: Prospective analysis of patients with refractive error presenting to the Ophthalmology outpatient services were included as cases. Age and sex matched emmetropic subjects were included as controls. Both cases and controls were undertaken for CCT measurements by ultrasonic pachymetry. Results: A total of 187 eyes as cases, 101 as controls. Among cases, 122 eyes myopic (Group- 1) (Mean CCT= 531.80±37.83 μ) and 65 hypermetropic (Group- 2) (Mean CCT=549.66±45.66 μ). The results shows that the central corneal thickness was decreased in the myopic eyes in comparison to the normal eyes which was statistically significantly (p=0.001). However in the hypermetropic group, no correlation was found between central corneal thickness and degree of hypermetropia. Conclusion: This study provides pilot data of CCT in different types of refractive errors in our set of rural population which helps us in understanding the variation of CCT with refractive errors.