Diurnal IOP fluctuation: not an independent risk factor for glaucomatous visual field loss in high-risk ocular hypertension.

Purpose: To establish whether intraocular pressure (IOP) fluctuations contribute to the risk of developing glaucoma in patients with high-risk ocular hypertension. Methods: Ninety patients included in the Malmo Ocular Hypertension Study were examined every 3 months with office-hours diurnal tension curves and computerised perimetry. Patients were followed up prospectively for 10 years or until glaucomatous visual field loss could be demonstrated. Poststudy data were included in the analyses, extending maximum follow-up to 17 years. Results: After 17 years, 37 patients had developed glaucomatous visual field defects. When applying univariate Cox regression analyses, mean IOP of all measurements during the prospective part of the study was a significant risk factor for developing glaucoma (95% confidence interval [CI] 1.08 - 1.39), while IOP fluctuations were almost significant ( 95% CI 0.98 - 1.93). When separating effects of mean IOP level and mean IOP fluctuation using Cox multiple regression analysis, only IOP level came out as significant ( 95% CI 1.09 - 1.38), and IOP fluctuations did not contribute to the risk ( 95% CI 0.80 - 1.60). IOP fluctuation depended linearly on IOP level ( p< 0.0001), i.e. IOP fluctuation was larger in eyes with higher IOP levels. Conclusion: IOP fluctuations were not an independent risk factor for the incidence of glaucomatous visual field loss in subjects with ocular hypertension

The effect of different criteria on the number of patients blind from open-angle glaucoma

<p>Abstract</p> <p>Background</p> <p>The prevalence of blindness and visual impairment from glaucoma is influenced by the criteria used to define these entities, which differ between countries and regions, as well as among published reports. The objective of the present study was to ascertain the extent to which different criteria of blindness and visual impairment influence estimates of the number of patients classified as blind or visually impaired by glaucoma in a clinic-based population.</p> <p>Methods</p> <p>We conducted a retrospective chart review of 914 patients with open-angle glaucoma to compare numbers of patients identified as visually impaired with and without considering visual field status. We also compared proportions classified using World Health Organisation (WHO) and United States (US) blindness criteria, and applying a new US Social Security Administration (SSA) disability criterion: perimetric mean deviation (MD) ≤ -22 dB.</p> <p>Results</p> <p>Forty patients (4.4%) were bilaterally blind from glaucoma by the WHO criteria. Fifty-two (5.7%) were blind by the the US criterion. Assessing only visual acuity, 14 (1.5%) patients were blind by the WHO criteria and 24 (2.6%) by the US definition. Eighty-five (9.3%) met the US SSA disability criterion. Among those, 52 were impaired also by the WHO definition. No patients impaired according to the WHO criteria had MD values better than -22 dB.</p> <p>Conclusions</p> <p>Excluding visual field status will seriously underestimate the prevalence of glaucoma blindness. In our patient population, 30% more patients were classified as blind by the US than by the WHO definition. Also, 60% more were identified as visually impaired by the US SSA criterion than by the WHO criteria. Visual field assessment is vital to determine visual impairment caused by glaucoma.</p

Lifetime Risk of Blindness in Open-Angle Glaucoma.

To determine the lifetime risk and duration of blindness in patients with manifest open-angle glaucoma (OAG)

Effects of Argon Laser Trabeculoplasty in the Early Manifest Glaucoma Trial.

PURPOSE: To analyze reduction of intraocular pressure (IOP) by argon laser trabeculoplasty (ALT) in the Early Manifest Glaucoma Trial and factors influencing the effect of such treatment. DESIGN: Cohort study based on 127 patients from the treatment group of the Early Manifest Glaucoma Trial, a randomized clinical trial. METHODS: Patients randomized to the treatment arm of the Early Manifest Glaucoma Trial received a standard treatment protocol (topical betaxolol hydrochloride followed by 360-degree ALT) and then were followed up prospectively at 3-month intervals for up to 8 years. One eye per patient was included in the analyses. We investigated the relationship between IOP before ALT and subsequent IOP reduction and other factors that might have influenced the effect of ALT, including stage of the disease, trabecular pigmentation, presence of exfoliation syndrome, and treating surgeon. RESULTS: The mean ± standard deviation IOP before ALT and after betaxolol treatment was 18.1 ± 3.9 mm Hg, and the mean ± standard deviation short-term IOP reduction 3 months after ALT was 2.8 ± 3.9 mm Hg (12.6 ± 20.5%). The IOP before ALT strongly affected IOP reduction (P < .001); each 3-mm Hg higher IOP before ALT value was associated with an additional mean IOP reduction of approximately 2 mm Hg. The treating surgeons also had a significant impact on IOP reduction (P = 0.001), with mean values ranging from 5.8 to -1.3 mm Hg. CONCLUSIONS: In this cohort, which included many patients with low IOP levels, IOP before ALT markedly influenced the IOP reduction induced by ALT, seen as a much larger decrease in eyes with higher IOP before ALT. The treating surgeon also had a significant impact on ALT outcome

The Effect of Education on the Assessment of Optic Nerve Head Photographs for the Glaucoma Diagnosis

Background: To evaluate the effect of one lesson of continuing medical education (CME) of subjective assessment of optic nerve head appearance on sensitivity and specificity for the diagnosis of glaucoma. Methods: Ophthalmologists and residents in ophthalmology attending an international glaucoma meeting arranged at Malmo University Hospital, Malmo, Sweden, were asked to grade optic nerve head (ONH) photographs of healthy and glaucomatous subjects at two sessions separated by a lecture on glaucoma diagnosis by ONH assessment. Each grader had access to an individual portfolio of 50 ONH photographs randomly selected from a web-based data bank including ONH photographs of 73 glaucoma patients and 123 healthy subjects. The individual portfolio of photographs was graded before and after the lecture, but in different randomized order. Results: Ninety-six doctors, 91% of all attending the meeting, completed both assessment sessions. The number of correct classifications increased from 69 to 72% on the average. Diagnostic sensitivity increased significantly (p < 0.0001) from 70% to 80%, and the number of photographs classified as uncertain decreased significantly (p < 0.0001) from 22% to 13%. Specificity remained at 68%, and intra-grader agreement decreased. Conclusion: CME had only a small effect on the assessment of ONH for the glaucoma diagnosis. Sensitivity increased and the amount of uncertain classifications decreased, while specificity was unchanged

Structural and Functional Progression in the Early Manifest Glaucoma Trial.

PurposeTo elucidate the temporal relationship between detection of glaucomatous optic disc progression, as assessed by fundus photography, and visual field progression.DesignProspective, randomized, longitudinal trial.ParticipantsThree hundred six study eyes with manifest glaucoma with field loss and 192 fellow eyes without any field defect at the start of the trial, from a total of 249 subjects included in the Early Manifest Glaucoma Trial (EMGT), were assessed.MethodsEvaluation of visual field progression and optic disc progression during an 8-year follow-up period. Three graders independently assessed optic disc progression in optic disc photographs. Visual field progression was assessed using glaucoma change probability maps and the EMGT progression criterion.Main Outcome MeasuresTime to detection of visual field progression and optic disc progression.ResultsAmong study eyes with manifest glaucoma, progression was detected in the visual field first in 163 eyes (52%) and in the optic disc first in 39 eyes (12%); in 1 eye (0%), it was found simultaneously with both methods. Among fellow eyes with normal fields, progression was detected in the visual field first in 28 eyes (15%) and in the optic disc first in 34 eyes (18%); in 1 eye (1%), it occurred simultaneously.ConclusionsIn eyes with manifest glaucoma, progression in the visual field was detected first more than 4 times as often as progression in the optic disc. Among fellow eyes without visual field loss at baseline, progression was detected first as frequently in the optic disc as in the visual field

Integration and fusion of standard automated perimetry and optical coherence tomography data for improved automated glaucoma diagnostics

<p>Abstract</p> <p>Background</p> <p>The performance of glaucoma diagnostic systems could be conceivably improved by the integration of functional and structural test measurements that provide relevant and complementary information for reaching a diagnosis. The purpose of this study was to investigate the performance of data fusion methods and techniques for simple combination of Standard Automated Perimetry (SAP) and Optical Coherence Tomography (OCT) data for the diagnosis of glaucoma using Artificial Neural Networks (ANNs).</p> <p>Methods</p> <p>Humphrey 24-2 SITA standard SAP and StratusOCT tests were prospectively collected from a randomly selected population of 125 healthy persons and 135 patients with glaucomatous optic nerve heads and used as input for the ANNs. We tested commercially available standard parameters as well as novel ones (fused OCT and SAP data) that exploit the spatial relationship between visual field areas and sectors of the OCT peripapillary scan circle. We evaluated the performance of these SAP and OCT derived parameters both separately and in combination.</p> <p>Results</p> <p>The diagnostic accuracy from a combination of fused SAP and OCT data (95.39%) was higher than that of the best conventional parameters of either instrument, i.e. SAP Glaucoma Hemifield Test (p < 0.001) and OCT Retinal Nerve Fiber Layer Thickness ≥ 1 quadrant (p = 0.031). Fused OCT and combined fused OCT and SAP data provided similar Area under the Receiver Operating Characteristic Curve (AROC) values of 0.978 that were significantly larger (p = 0.047) compared to ANNs using SAP parameters alone (AROC = 0.945). On the other hand, ANNs based on the OCT parameters (AROC = 0.970) did not perform significantly worse than the ANNs based on the fused or combined forms of input data. The use of fused input increased the number of tests that were correctly classified by both SAP and OCT based ANNs.</p> <p>Conclusions</p> <p>Compared to the use of SAP parameters, input from the combination of fused OCT and SAP parameters, and from fused OCT data, significantly increased the performance of ANNs. Integrating parameters by including a priori relevant information through data fusion may improve ANN classification accuracy compared to currently available methods.</p

Lack of Visual Field Improvement After Initiation of Intraocular Pressure Reducing Treatment in the Early Manifest Glaucoma Trial

PURPOSE. We evaluate how visual fields are affected by the initiation of IOP-reducing therapy in previously untreated glaucoma individuals. METHODS. Qualifying individuals with newly diagnosed glaucoma having normal to moderately elevated IOP were prospectively randomized either to IOP-reducing therapy or to no treatment. Before randomization, individuals underwent repeatedly Standard Automated Perimetry (SAP) testing and Goldmann tonometry. Three months after randomization, patients again underwent SAP and tonometry. Changes between baseline and the 3-month follow-up visit in the perimetric summary index, mean deviation (MD), and total deviation values at significantly depressed test points were compared between the treated and untreated groups. RESULTS. Of 255 individuals studied, 129 were randomized to treatment and 126 to no treatment. Intraocular pressure decreased by an average of 24% among treated and by 0.6% in the untreated patients. Mean deviation deteriorated slightly in both groups; mean change was À0.15 and À0.44 dB in the treated and untreated groups, respectively; the difference was not statistically significant, (P ¼ 0.16). No association was seen between IOP reduction and change in MD. Sensitivities decreased slightly in significantly depressed test points, mean change was À0.45 dB in the untreated and À0.38 dB in the treated groups (P ¼ 0.88). CONCLUSIONS. Observed visual field changes among glaucoma patients receiving initial IOPreducing therapy were not significantly different to changes seen in patients who received no treatment. Thus, our results did not support the idea that visual field status improves after initiation of IOP-reducing therapy in glaucoma individuals, at least not in individuals with initially normal to moderately elevated IOPs