Dynamic contour tonometry in primary open angle glaucoma and pseudoexfoliation glaucoma: factors associated with intraocular pressure and ocular pulse amplitude

To compare the intraocular pressures [IOP] and ocular pulse amplitudes [OPAs] in patients with primary open-angle glaucoma [POAG] and pseudoexfoliation glaucoma [PXG], and to evaluate ocular and systemic factors associated with the OPA. In this prospective study, on 28 POAG and 30 PXG patients, IOP was measured with the Goldmann applanation tonometry [GAT] and the Pascal dynamic contour tonometry [DCT]. Other measurements included central corneal thickness [CCT], vertical cup-to-disc ratio [CDR], and systolic and diastolic blood pressure. Statistical significance was defined as P< 0.05. In each of the POAG and PXG groups, GAT IOP was correlated with CCT [r = 0.40, P -= 0.03 and r= 0.35, P =0.05, respectively], whereas DOT IOP and CCT were not correlated. In all patients and in the POAG group, OPA was positively correlated with DCT IOP [r= 0.39, P = 0.002]. OPA was not correlated with CCT in the POAG [P= 0.80], nor in the PXG [P = 0.20] group, after adjusting for DCT IOP When corrected for DCT IOP and CCT, there was a significant negative correlation between OPA and vertical CDR in all patients [r= - 0.41, P = 0.002]. There was no significant difference in OPAbetween groups [P= 0.55], even when OPA was adjusted for IOP and systolic and diastolic pressure [P= 0.40], in a linear regression model. DCT IOP and OPA are not correlated with CCT. There is no significant difference between the OPA of PXG and POAG eyes. OPA is correlated with DCT IOP, and is lower in eyes with more advanced glaucomatous cupping

Central corneal thickness in Iranian congenital glaucoma patients

To compare central corneal thickness [CCT] in subjects with controlled primary congenital glaucoma [PCG] and nonglaucomatous subjects and to investigate the correlation between CCT and intraocular pressure [IOP] in the study population. Twenty-three consecutive PCG cases with controlled IOP and no clinical evidence of corneal edema comprised the Study Group. There was an interval of at least 2 months between last intraocular surgery and inclusion in the study. Twenty-one subjects with strabismus or lacrimal drainage insufficiency who did not have glaucoma or any history of intraocular surgery or ocular trauma comprised the control group. The Control Group was age and sex-matched. Data from ultrasonic pachymetry and applanation tonometry were analyzed for differences between groups. Correlation of the study parameters was investigated. A P-value less than 0.05 was statistically significant. Data from both eyes of subjects in the Study Group and Control Group were included in the original analysis. Mean CCT was statistically significantly higher in the Study Group compared to the Control Group [589.42 +/- 53.44 æm vs. 556.14 +/- 30.51 æm, respectively; P=0.001]. There was a significant correlation between CCT and IOP [r=0.63; P<0.0001]. Similar statistically significant outcomes were observed when only one eye per subject was used in a reanalysis of the data for the Study and Control Groups. Patients with PCG who had controlled IOP have statistically significantly thicker corneas than nonglaucomatous age and sex-matched subjects The thicker cornea could significantly alter IOP measurement with applanation tonometry. Pachymetry should be considered an essential part of the evaluation for PCG

Lack of association between the C677T single nucleotide polymorphism of the MTHFR gene and glaucoma in Iranian patients

Glaucoma is a major cause of blindness worldwide. A single nucleotide polymorphism of the MTHFR gene [C677T] has been associated with susceptibility to this disease, although this is controversial in the last decade. In this study, the possible association between the MTHFR C677T polymorphism and the risk of developing primary open angle [POAG] and pseudoexfoliation glaucoma [PEXG] was investigated. For this, a prospective study consisting of 73 POAG, 85 PEXG and 90 matched controls was undertaken in an Iranian population. Genomic DNA was extracted from whole blood. Genotyping of all individuals for the MTHFR C677T polymorphism was conducted using the PCR-RFLP technique. Our findings revealed no significant association between the MTHFR C677T polymorphism in POAG and PEXG compared with controls. Consistent with several other studies, our analysis suggests that the MTHFR C677T polymorphism is unlikely to be a factor contributing to the risk of developing specific forms of glaucoma

Primary open-angle glaucoma risk factors

The objective of this study was to identify possible risk factors associated with primary open-angle glaucoma [POAG]. A case-control study included patients seen at Rasoul-Akram Hospital ophthalmology clinic. Cases were consecutive patients with confirmed unilateral or bilateral POAG presented during the study period. Controls were a random sample of all other patients aged 30 or more, seen in the same department in the same period who were randomly selected if they fulfilled the inclusion criteria and then matched with the cases by age and sex. Data on demographic, anthropometric as well as medical characteristics were collected from 191 subjects, by interview and medical examination. Sixty consecutive patients with POAG and 131 controls were chosen. Odds ratios [OR] are calculated for the relation between POAG and family history of glaucoma, body mass index, hypertension, diabetes mellitus. cigarette smoking, migraine, and refractive error Chi-square and student t tests were used. Results indicated the following: family history of glauccma: OR: 35, 95% Cl: 4.57-282.43, P<0.0001, hyperopia: OR: 0.432, 95% Cl: 0.209-0.893, P=0.021, hypertension: OR: 1.46, 95% Cl: 0.78-2.73, P=0.223, body mass index: P=0.378 [student t test], migraine: OR: 0.46, 95% Cl: 0.098-2.23, P=0.507, and cigarette smoking: OR: 1.81; 95% Cl, 0.747-4.41; P= 0.184. This study replicated the finding that family history is a major risk factor for POAG [when adjusting for age and sex], while it failed to show that hypertension, diabetes mellitus, myopia, cigarette smoking, migraine, and body mass index to be associated with POAG. It also suggested a protective role for hyperopia in POAG