Evidence Of Glaucoma Research Articles

One-Year Postoperative Outcomes following Transfixion of Foldable Intraocular Lens with Polytetrafluoroethylene Suture for Scleral Fixation

We examined 19 eyes of 19 patients. Significant improvement in visual acuity was noted in all cases. In addition, most of the IOLs (84.21%) were well centered, and 3 eyes (15.78%) presented mild inferior decentration. Only one eye (5.26%) developed mild pigment dispersion with no evidence of glaucoma.

Investigation of correlation between corneal thickness and intraocular pressure in New Zealand Albino Rabbits

The aim of this study was to determine intraocular pressure (IOP) and central corneal thickness (CCT) measurements in healthy rabbits to establish clinical reference values and to investigate the possible relationship between these measurements. The study included 40 eyes of 20 New Zealand albino rabbits, aged 1.5-2 years. All the eyes were healthy with no abnormalities, corneal disease, or evidence of glaucoma. An ultrasonographic pachymeter was used to measure CCT and TonoVet® was used to measure IOP. Correlations between IOP and CCT measurements were examined. The mean CCT was 388.2 ± 38.22 µm in the right eye and 391.8± 59.18 µm in the left eye. IOP was measured as 16 ± 3.76 mmHg in the right eye and 16 ± 2.73 mmHg in the left eye. No correlation was determined between the IOP and CCT, and this indicated that the TonoVet® readings of CCT and IOP did not cause a deviation that could be determined. There is a need for further studies of different animals to investigate the effect of corneal thickness on the IOP measurements made with TonoVet®.

Diagnostic Accuracy and Detection Rate of Glaucoma Screening with Optic Disk Photos, Optical Coherence Tomography Images, and Telemedicine.

Purpose: The aim of this study was to evaluate the diagnostic accuracy of optical coherence tomography (OCT) and retinography in the detection of glaucoma through a telemedicine program. Methods: A population-based sample of 4113 persons was randomly selected. The screening examination included a fundus photograph and OCT images. Images were evaluated on a deferred basis. All participants were then invited to a complete glaucoma examination, including gonioscopy, visual field, and dilated fundus examination. The detection rate, sensitivity, specificity, and positive and negative predictive values were calculated. Results: We screened 1006 persons. Of these, 201 (19.9%) were classified as glaucoma suspects; 20.4% were identified only by retinographs, 11.9% only by OCT images, and 46.3% by both. On ophthalmic examination at the hospital (n = 481), confirmed glaucoma was found in 58 (12.1%), probable glaucoma in 76 (15.8%), and ocular hypertension in 10 (2.1%), and no evidence of glaucoma was found in 337 (70.0%). The detection rate for confirmed or probable glaucoma was 9.2%. Sensitivity ranged from 69.4% to 86.2% and specificity from 82.1% to 97.4%, depending on the definition applied. Conclusions: The combination of OCT images and fundus photographs yielded a detection rate of 9.2% in a population-based screening program with moderate sensitivity, high specificity, and predictive values of 84–96%.

Evaluation of non-exudative microcystoid macular abnormalities secondary to retinal vein occlusion

PurposeWe aimed to investigate non-exudative microcystoid macular abnormalities for visual and anatomical outcome in patients with retinal vein occlusion (RVO) with and without glaucomatous optic neuropathy (GON).MethodsMedical records of 124 eyes (105 patients) with RVO were reviewed and analyzed. Eyes demonstrating microcystoid macular abnormalities were divided into 2 groups, those with evidence of glaucoma (group A) and those without glaucoma (group B). Best-corrected visual acuity (BCVA), the prevalence and number of microcystoid macular abnormalities, and number of intravitreal anti-vascular endothelial growth factor (anti-VEGF) injections were compared at baseline and follow-up.ResultsSeventy-one out of 105 eyes (67.6%) with RVO displayed microcystoid macular abnormalities. Thirty-eight out of 71 eyes (53.5%) presented with concomitant glaucoma (group A), while the remaining 33 eyes (42.6%) had no history of glaucoma (group B). At the end of the follow-up period, mean BCVA was worse in group A versus group B (20/80 versus 20/40, respectively; p = .003). The mean number of anti-VEGF injections was 10.1 ± 9.2 in group A versus 5.9 ± 6.9 in group B (p = .03).ConclusionEyes with RVO and concomitant glaucoma exhibited a significantly higher number of microcystoid macular abnormalities and worse BCVA versus eyes with RVO without glaucoma.

Anterior chamber angle in aniridia with and without glaucoma.

PurposeWe performed a retrospective, comparative study to determine if patients with aniridia and glaucoma had open angles on high-resolution anterior segment optical coherence tomography (OCT) and clinical gonioscopy.Patients and methodsForty-three patients (86 eyes) with aniridia had recorded anterior segment OCTs, gonioscopy, or both. Of these patients, 27 (54 eyes) were diagnosed with glaucoma and 16 (32 eyes) had no evidence of glaucoma. All patients had either anterior segment OCT, gonioscopy, or both.ResultsThe 43 patients with aniridia had average age of 32±17 years, and 27 (62%) were female. Anterior segment OCT and gonioscopy were recorded in 25 (58%) of the patients and 18 (42%) of the patients had gonioscopy alone. Of the 54 eyes with aniridia and glaucoma, 4 (7%) eyes in 3 patients (11%) had partial or completely closed angles. Of the 32 eyes without glaucoma, all (100%) had open angles. The proportion of open angles in the aniridia with glaucoma eyes was not significantly different compared with the aniridia without glaucoma eyes (P=0.32). Of the 4 eyes with closed angles, all had a history of prior surgery for cataract, glaucoma, and/or keratopathy. The proportion of eyes with prior surgery was significantly higher in eyes with open-angle glaucoma and angle-closure glaucoma compared with eyes without glaucoma (P<0.001 and P=0.002, respectively).ConclusionThe majority of eyes with aniridia and glaucoma have open anterior chamber angles, similar to patients with aniridia without glaucoma. All eyes with aniridia and glaucoma that had closed angles had a prior history of ocular surgery.

Retinal Nerve Fiber Layer Thickness in Human T-cell Lymphotropic Virus Type 1 Patients

ABSTRACTPurpose: To determine whether there is an optic neuropathy (ON) in patients with human T-cell lymphotropic virus type 1 (HTLV-1) infection.Methods: We included HTLV-1 asymptomatic carriers (a.c.HTLV-1) and tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM) patients between January 1st, 2014 and March 31st, 2015. All patients had complete eye examination. The visual acuity (VA) and retinal nerve fiber layer (RNFL) thickness were measured and compared to age- and sex-matched control groups including patients seen in our refraction clinic with no previous medical or surgical history.Results: Thirty-one a.c.HTLV-1 (group 1) and 29 TSP/HAM patients (group 2) were included. The average RNFL thickness was 99.9 ± 14.3 µm in group 1 and 87.8 ± 19.2 µm in group 2. The average RFNL thicknesses were lower in both groups, when compared to controls. The difference was significant in patients with TSP/HAM (87.8 ± 19.2 µm vs. 97 ± 7.8 µm; p = 0.003) who also had significantly decreased VA.Conclusions: We report here the first study about the RNFL thickness in patients with TSP/HAM. In these patients, there is decrease of the RNFL thickness with subtle but definite decrease of VA. This suggests that subclinical ON occurs in the natural history of the disease. The diagnosis of TSP/HAM must be evoked as a differential of primary progressive multiple sclerosis in a population at risk. Moreover, RNFL thinning with no evidence of glaucoma should raise suspicion for HTLV-1 infection and TSP/HAM in a population at risk.

Modified technique of endocapsular lens aspiration for severely subluxated lenses.

PurposeSeverely subluxated crystalline lenses pose a difficult situation to anterior segment surgeons and can only be managed surgically by removal of the lens as well as the capsular bag. Several techniques have been described in literature for the management of such cases. We describe a modified technique of endocapsular lens aspiration by the limbal route for lens extraction through small incisions on the cornea.Patients and methodsThirty-two eyes of 16 consecutive patients with severely subluxated crystalline lenses were recruited in the study. All eyes underwent a modified technique of lens aspiration within the capsular bag using a single instrument, vitrectomy cutter, and irrigation cannula, followed by sacrificing of the capsular bag. The patients were either left aphakic or implanted with an open loop anterior chamber intraocular lens (ACIOL Kelman Multiflex) and prospectively followed up for a period of 3 months.ResultsThe mean age of the patients was 9 years 3 months±3 years (range 5-15 yrs). All eyes underwent complete lens aspiration within the capsular bag with no dislocation of the lens matter. ACIOL was inserted in 22 eyes (68.7%) and 10 eyes (31.2%) were left aphakic. All the surgeries were uneventful. The mean best corrected visual acuity (BCVA) at 3 months post surgery was 0.47±0.11 logMAR which was significantly better than pre-operative BCVA (P=0.001). The percentage endothelial cell loss at 3 months was 7.1%. There was no evidence of glaucoma, corneal decompensation, or retinal detachment. The astigmatism which increased from 1.45D±086 preoperatively to 3.76D±2.02 1 week post-operatively due to sutures reduced to 1.97D±0.81 post suture removal at 3 months.ConclusionThe modified technique of endocapsular lens aspiration proves to be a simple and effective method of removal of the lens-capsular bag complex in severely subluxated lenses.

Glaucoma Screening in Nepal: Cup-to-Disc Estimate With Standard Mydriatic Fundus Camera Compared to Portable Nonmydriatic Camera

To compare cup-to-disc ratio (CDR) measurements from images taken with a portable, 45-degree nonmydriatic fundus camera to images from a traditional tabletop mydriatic fundus camera. Prospective, cross-sectional, comparative instrument validation study. Setting: Clinic-based. A total of 422 eyes of 211 subjects were recruited from the Tilganga Institute of Ophthalmology (Kathmandu, Nepal). Two masked readers measured CDR and noted possible evidence of glaucoma (CDR ≥ 0.7 or the presence of a notch or disc hemorrhage) from fundus photographs taken with a nonmydriatic portable camera and a mydriatic standard camera. Each image was graded twice. Effect of camera modality on CDR measurement; inter- and intraobserver agreement for each camera for the diagnosis of glaucoma. A total of 196 eyes (46.5%) were diagnosed with glaucoma by chart review; 41.2%-59.0% of eyes were remotely diagnosed with glaucoma over grader, repeat measurement, and camera modality. There was no significant difference in CDR measurement between cameras after adjusting for grader and measurement order (estimate= 0.004, 95% confidence interval [CI], 0.003-0.011, P= .24). There was moderate interobserver reliability for the diagnosis of glaucoma (Pictor: κ= 0.54, CI, 0.46-0.61; Topcon: κ= 0.63, CI, 0.55-0.70) and moderate intraobserver agreement upon repeat grading (Pictor: κ= 0.63 and 0.64, for graders 1 and 2, respectively; Topcon: κ= 0.72 and 0.80, for graders 1 and 2, respectively). A portable, nonmydriatic, fundus camera can facilitate remote evaluation of disc images on par with standard mydriatic fundus photography.

Intravitreal Anti-VEGF Injections Reduce Aqueous Outflow Facility in Patients With Neovascular Age-Related Macular Degeneration.

PurposeWe assess the effect of intravitreal anti-VEGF injections on tonographic outflow facility.MethodsPatients with age-related macular degeneration who had received unilateral intravitreal anti-VEGF injections were recruited into two groups, those with ≤10 and those with ≥20 total anti-VEGF injections. Intraocular pressure and tonographic outflow facility of injected and uninjected fellow eyes were measured and compared between groups. Risk factors for development of reduced outflow facility also were assessed.ResultsOutflow facility was 12% lower in the injected eyes of patients who received ≥20 anti-VEGF injections, compared to contralateral uninjected eyes (P = 0.02). In contrast, there was no facility reduction for patients with ≤10 anti-VEGF injections (P = 0.4). In patients with ocular hypertension in the uninjected eye (IOP > 21 mm Hg, n = 5), the outflow facility of injected eyes was on average 46% lower (P = 0.01) than in the uninjected fellow eyes. This was significantly greater than the difference observed in patients with IOP ≤ 21 mm Hg in the uninjected eye (P = 2 × 10−4). In patients with ocular hypertension in the injected eye (n = 6) the differences in facility and IOP between contralateral eyes were significantly greater than in patients with IOP ≤ 21 mm Hg in the injected eye (P = 2 × 10−4 and P = 7 × 10−4, respectively).ConclusionsChronic anti-VEGF injections significantly reduce outflow facility in patients with AMD. The greatest facility reduction is observed in patients with baseline ocular hypertension. Ophthalmologists who administer anti-VEGF injections should be aware of these findings and monitor patients closely for changes in IOP or evidence of glaucoma, especially in those with pre-existing ocular hypertension.

Correlation Between Intraocular Pressure and Central Corneal Thickness in Persian Children.

IntroductionThis study aimed to determine intraocular pressure (IOP) and central corneal thickness (CCT) measurements in healthy Persian children to find clinical reference values in this ethnicity. Additionally, we examined the possible relationship between these measurements.MethodsThis cross-sectional study included 262 eyes of 131 Persian primary school children between 6 and 13 years of age. All eyes were healthy and had no anterior or posterior segment abnormalities, corneal disease, or evidence of glaucoma. Specular microscopy was used to measure CCT and both noncontact tonometry (NCT) and Goldmann applanation tonometer (GAT) were used to measure IOP. Correlations between IOP measurements were also examined.ResultsMean CCT was 513.47 ± 34.51 μm in the right eye (OD) and 513.93 ± 33.88 μm in the left eye (OS). The CCT was not significantly different between older (10–13 years) and younger (6–9 years) patients. Mean IOP measured with GAT was 13.86 ± 2.13 mmHg OD and 13.72 ± 2.04 mmHg OS and mean IOP measured with NCT was 15.26 ± 2.38 mmHg OD and 15.11 ± 2.18 mmHg OS. The IOP and CCT measured with GAT were weakly correlated (OD: r = 0.141, P = 0.114; OS: r = 0.236, P = 0.007). However, IOP and CCT measured with NCT (OD: r = 0.487, P = 0.000; OS: r = 0.456, P = 0.000) were moderately correlated. Our outcomes demonstrated that for 100 μm increase in CCT, IOP measured with GAT and NCT increased by 0.8 and 3.3 mmHg, respectively, in OD and by 1.4 and 2.9 mmHg in OS. Based on intraclass correlation coefficients, IOP measurements made with GAT and NCT were in fair agreement in OD and in good agreement in OS.ConclusionThe IOP and CCT in healthy Persian school children (6–13 years old) were positively correlated. Our findings revealed that corneal thickness is thinner in Persian children than in most other racial groups.FundingThis study has been funded by deputy dean in research of School of Medicine and deputy vice chancellor of Shiraz University of Medical Sciences, Shiraz, Iran.

Effect of head tilt on repeatability of optic nerve head parameters using cirrus spectral-domain optical coherence tomography.

To assess the repeatability of measuring optic nerve head (ONH) parameters using the Cirrus optical coherence tomography (OCT), as well as to assess the effect of head tilt on these measurements. Thirty healthy participants with no evidence of glaucoma were recruited for the study. Visual acuity, intraocular pressure, standard automated perimetry and ocular examination were performed for each participant. One eye was then randomly selected and scanned undilated with the Cirrus OCT in 3 positions (neutral, 30° right tilt and 30° left tilt). Data collected from 29 eyes were used for analysis. One patient was omitted due to poor scan quality. The repeatability of the ONH parameters was analyzed using analysis of variance, coefficient of variation (COV) and intraclass correlation coefficient (ICC). Analysis of variance showed no statistically significant difference between 3 scans in a single position. There was good agreement between measurements (ICC 0.919-0.996, COV 1.94%-5.48%). Even with the presence of head tilt, repeated scans in the 3 positions showed good agreement as well (ICC 0.888-0.996, COV 2.04%-5.39%). Serial measurements of ONH parameters using the Cirrus OCT are found to have good repeatability. The ONH parameters with Cirrus OCT also maintain good repeatability despite head tilt.

Elevated Intraocular Pressure After Intravitreal Steroid Injection in Diabetic Macular Edema: Monitoring and Management.

IntroductionWith the increasing use of intravitreal administration of corticosteroids in macular edema, steroid-induced intraocular pressure (IOP) rise is becoming an emergent issue. However, for patients in whom intravitreal steroids are indicated, there are no specific recommendations for IOP monitoring and management after intravitreal administration of corticosteroids.MethodAn expert panel of European ophthalmologists reviewed evidence on corticosteroid-induced IOP elevation. The objective of the panel was to propose an algorithm based on available literature and their own experience for the monitoring and management of corticosteroid-induced IOP elevation, with a focus on diabetic patients.ResultsData from trials including diabetic patients with a rise of IOP after intravitreal steroid administration indicate that IOP-lowering medical treatment is sufficient for a large majority of patients; only a small percentage underwent laser trabeculoplasty or filtering filtration surgery. A 2-step algorithm is proposed that is based on the basal value of IOP and evidence for glaucoma. The first step is a risk stratification before treatment. Patients normotensive at baseline (IOP ≤ 21 mmHg), do not require additional baseline diagnostic tests. However, patients with baseline ocular hypertension (OHT) (IOP > 21 mmHg) should undergo baseline imaging and visual field testing. The second step describes monitoring and treatment after steroid administration. During follow-up, patients developing OHT should have baseline and periodical imaging and visual field testing; IOP-lowering treatment is proposed only if IOP is >25 mmHg or if diagnostic tests suggest developing glaucoma.ConclusionThe management and follow-up of OHT following intravitreal corticosteroid injection is similar to that of primary OHT. If OHT develops, IOP is controlled in a large proportion of patients with standard IOP treatments. The present algorithm was developed to assist ophthalmologists with guiding principles in the management of corticosteroid-induced IOP elevation.FundingAlimera Sciences Limited.

Anterior Chamber Morphometry before and after Cataract Surgery

Purpose: To quantify the effects of cataract surgery on the anterior chamber topography in patients with angleclosure glaucoma (PACG), open-angle glaucoma (POAG) and patients with no evidence of glaucoma or ocular hypertension. Materials and methods: 170 eyes of 119 patients undergoing phacoemulsification, followed by posterior chamber intraocular lens implantations (PC IOL), were divided into three groups as follows: PACG (50 eyes, 28 patients), POAG (40 eyes, 29 patients) and a control group (80 eyes, 62 patients). The Pentacam rotating Scheimpflug camera measured the following changes that occurred in the anterior chamber: depth (ACD), volume (ACV), angle (ACA) and central corneal thickness (CCT). Additionally, Goldmann applanation tonometry was used to evaluate intraocular pressure (IOP). All measurements were first taken preoperatively and subsequently at 3 weeks and 3 months postoperatively. Results: When measured at 3 weeks and 3 months postoperatively, the mean ACD, ACV and ACA increased in all groups (p 0.05). We also found insignificant postoperative pachymetric changes when compared to the preoperative period (p>0.05). The IOP decreased throughout all postoperative periods in all groups, though mostly in PACG eyes (p<0.05). Conclusions: Cataract surgery significantly increased ACD, ACV and ACA in all study groups. The surgery respectively decreased IOP and induced insignificant changes of CCT.

Nigeria Normative Data for Defining Glaucoma in Prevalence Surveys

ABSTRACTPurpose: To determine normative values for defining glaucoma in cross-sectional surveys in Nigerian adults.Methods: Multistage stratified cluster random sampling with probability-proportional-to-size procedures to select a nationally representative sample of 15,027 persons aged ≥40 years in 305 clusters across Nigeria. Systematic sampling of 1 in 7 participants gave 1759 who were examined in detail to construct a normative database. The normative subset was used to determine values for vertical cup/disc ratio (VCDR) and intraocular pressure (IOP) for glaucoma diagnosis according to the International Society of Geographical and Epidemiological Ophthalmology (ISGEO) criteria. Examinations included visual field testing by frequency doubling technology (FDT), Goldmann applanation tonometry, and optic disc image grading by Moorfields Eye Hospital Reading Centre.Results: In the normative dataset, 1057/1759 persons (60.1%) had normal FDTs, and constituted the hypernormal. Of these, 851 had VCDR and 973 had IOP measurements taken in both eyes. For category 1 (structural and functional evidence of glaucoma), the 97.5th percentile VCDR was 0.7. For category 2 (advanced structural damage with unproven visual field loss), the 99.5th percentile VCDR was 0.75. In addition, asymmetry in VCDR was 0.1 difference at the 97.5th percentile and 0.2 difference at the 99.5th percentile. Category 3 criteria were used when the optic disc was not visible and field testing not possible; 99.5th percentile IOP is one criterion (28 mmHg).Conclusion: While these results do not differentiate between open-angle and angle-closure mechanisms, they can be applied to determine the prevalence of glaucoma in Nigeria and sub-Saharan African countries with similar sociodemographic characteristics.

Prevalence of angle closure in siblings of patients with primary angle-closure glaucoma.

To determine the frequency of angle closure in siblings of patients with primary angle-closure glaucoma (PACG). In this cross-sectional observational study, siblings of consecutive patients with PACG underwent a comprehensive ophthalmologic examination, including slit-lamp biomicroscopy, measurement of intraocular pressure, stereoscopic optic nerve head examination, and dynamic gonioscopy. Ultrasonic pachymetry was obtained in all subjects; peripapillary retinal nerve fiber layer thickness measurement by optical coherence tomography and standard achromatic perimetry were performed in subjects with angle closure, categorized as primary angle-closure suspect (PACS), primary angle closure (PAC), and PACG, or any suspicion of glaucoma in the presence of open angles. Overall, 95 siblings from 47 families with at least 1 subject affected with PACG participated in the evaluations; 55 (57.9%) individuals were categorized within the spectrum of angle closure, including 34 (35.8%) subjects with PACS, 7 (7.4%)individuals with PAC, and 14 (14.7%) cases of PACG. Nine (9.5%) individuals with open angles demonstrated other abnormal features, these included 3 (3.2%) subjects with suspicious discs, 5 (5.3%) cases of primary open-angle glaucoma, and 1 patient (1.1%) with normal-tension glaucoma. The remaining 31 individuals (32.6%) had no evidence of glaucoma. Our findings indicate familial segregation of angle closure. Siblings of PACG patients are at high risk for the condition, such that two thirds of them demonstrate clinical findings related to glaucoma. These observations suggest a hereditary basis for angle closure; therefore, siblings of patients affected with angle closure should undergo targeted screening for glaucoma.

Six-year incidence of ocular hypertension in a South Indian population: the Chennai eye disease incidence study

AimsTo report the 6-year incidence and risk factors for ocular hypertension (OHT) in a population-based study in southern India.Methods6 years after baseline evaluation, 56.9% subjects (participants:non-participants, 4421:3353) were re-examined at...

Correlation between ocular perfusion pressure and ocular pulse amplitude in glaucoma, ocular hypertension, and normal eyes

BackgroundThe purpose of this study was to investigate the correlation between ocular perfusion pressure and ocular pulse amplitude in glaucoma, ocular hypertension, and normal eyes.MethodsNinety eyes from 90 patients were included. Thirty patients had been recently diagnosed with glaucoma and had no previous history of treatment for ocular hypotension, 30 had elevated intraocular pressure (IOP) without evidence of glaucoma, and 30 had normal IOP (<21 mmHg) with no detectable glaucomatous damage. Goldmann applanation tonometry (GAT), dynamic contour tonometry (DCT), blood pressure measurement, pachymetry, Humphrey visual field, and routine ophthalmic examination was performed in each patient. Ocular perfusion pressure was calculated as the difference between mean arterial pressure and IOP. The ocular pulse amplitude was given by DCT. The Pearson correlation coefficient was used to compare the glaucomatous and ocular hypertensive groups, and comparisons with the normal IOP group were done using the Spearman’s rank correlation coefficient.ResultsMean IOP by DCT was 22.7 ± 4.3 mmHg in the glaucoma group, 22.3 ± 2.8 mmHg in the ocular hypertension group, and 14.3 ± 1.6 mmHg in the control group. Mean IOP by GAT was 19.0 ± 5.1 mmHg for glaucoma, 22.4 ± 2.1 mmHg for ocular hypertension, and 12.9 ± 2.2 mmHg for controls. Mean ocular pulse amplitude was 3.4 ± 1.2 mmHg in the glaucoma group, 3.5 ± 1.2 mmHg in the ocular hypertension group, and 2.6 ± 0.9 mmHg in the control group. Mean ocular perfusion pressure was 46.3 ± 7.9 mmHg in the glaucoma group, 46.3 ± 7.9 mmHg in the ocular hypertension group, and 50.2 ± 7.0 mmHg in controls. No significant correlation between ocular perfusion pressure and ocular pulse amplitude was found in any of the groups (P = 0.865 and r = −0.032, P = 0.403 and r = −0.156, P = 0.082 and ρ = −0.307 for glaucoma, ocular hypertension, and normal eyes, respectively).ConclusionThere is no significant correlation between ocular perfusion pressure and ocular pulse amplitude values in glaucoma, ocular hypertension, or normal eyes. IOP values measured by GAT correlate with those measured by DCT.

A Study of Central Corneal Thickness in Glaucoma and Nonglaucoma Patients in a West African Population

To compare central corneal thickness (CCT) in high-tension glaucomatous eyes and nonglaucomatous eyes with normal intraocular pressure (IOP) and to determine if there is any correlation between CCT and severity of glaucoma, as indicated by vertical cup-to-disc ratio. A case-control study that involved 506 subjects at the Korle-Bu Teaching Hospital, Accra, Ghana, from August 2006 to July 2007. The cases were patients with (high tension and IOP more than 21 mm Hg) primary open-angle glaucoma, and the controls were patients with normal IOP (less than 21 mm Hg) and no evidence of glaucoma. The main outcome measures were CCT, as measured by ultrasonic pachymetry (model DGH 55 pachmate), and vertical cup-to-disc ratio. Five hundred six subjects were recruited: 253 cases (506 eyes) and 253 controls (505 eyes). The mean CCT of the right eye for the glaucoma cases was 524.28 μm [95% confidence interval (CI), 4.44; SD, 36.85] and for the controls was 530.00 μm (95% CI, 4.56; SD, 35.75). The mean CCT of the left eye for the glaucoma cases was 524.70 μm (95% CI, 4.48; SD, 36.20) and for the controls was 531.06 μm (95% CI, 4.40; SD, 35.52). The relation between CCT and cupping determined by Pearson correlation coefficient yielded values of -0.09 and 0.01 for the right and left eyes, respectively. There was no significant difference between mean CCT of cases and controls in the right eye (P = 0.08), but there was a weakly significant difference in the CCT of the left eye (P = 0.05). Also, there was no correlation between cup-to-disc ratio and CCT.

The Association between Retinal Vessel Diameter and Retinal Nerve Fiber Layer Thickness in Asymmetric Normal Tension Glaucoma Patients

The aim of this study was to evaluate the associations between retinal vessel diameter and retinal nerve fiber layer (RNFL) thickness in patients with normal tension glaucoma (NTG). This study included 67 untreated patients with asymmetric NTG, with no evidence of glaucoma in the contralateral eyes, and 48 age- and sex-matched normal control subjects. We included patients from 20 to 70 years of age who had no history of hypertension, diabetes, or other vascular diseases. All subjects underwent detailed eye examinations that included red-free photography, stereoscopic optic disc photography, automated perimetry, and measurement of RNFL thickness with optical coherence tomography. We compared RNFL thicknesses, temporal retinal arteriolar diameters (TRAD), and temporal retinal venular diameters (between quadrants with and without RNFL defects) with computer-assisted imaging software. The mean diameter of the temporal retinal vessels in the quadrants with RNFL defects were significantly smaller in patients with NTG than in those with quadrants without RNFL defects (P < 0.001) and in control subjects (P < 0.001). TRADs were correlated with RNFL defects and RNFL thicknesses (P < 0.05) in binary logistic regression analysis and in multiple linear regression analysis (P < 0.001). There were no statistically significant differences between vessel diameters in control subjects and those in nondefective quadrants of the affected NTG eyes or the unaffected eyes of patients with NTG. Our results show that narrower retinal vessels are found in areas of RNFL defects. Considering previous reports and our analysis, this is likely due to the decreased demand for retinal blood flow in damaged areas of the retina.

Concurrent presentation of aniridia and megalocornea without glaucoma

We report an 18-month-old boy who presented with aniridia and megalocornea but no evidence of glaucoma. In children with aniridia, glaucoma often does not present with buphthalmos; because, it typically manifests in preadolescence or adolescence, as progressive changes occur in the drainage angle. Megalocornea, however, in the presence of aniridia strongly suggests glaucoma in early infancy. This case represents a previously unreported association of aniridia and megalocornea in an otherwise-healthy child with good vision.