The assessment of disability related to vision performance-based measure in diabetic retinopathy.

PURPOSE: To validate a third-generation performance-based measure of visual function titled Assessment of Disability Related to Vision (ADREV) in a study population of patients with diabetic retinopathy. DESIGN: Prospective, cross-sectional study. METHODS: Patients with nonproliferative or proliferative diabetic retinopathy, free from ocular comorbidity, were recruited from a single institute and completed the ADREV, the 25-Item National Eye Institute Visual Functioning Questionnaire (VFQ-25), and a clinical ophthalmic examination. Correlation, regression, and bootstrap analysis were conducted to determine the relationship between ADREV scoring and each of the study\u27s clinical and self-report measures of visual ability, while controlling for potential confounders. RESULTS: Ninety-one patients with diabetic retinopathy completed the study and analysis showed that the ADREV total and subscale scores shared a stronger relationship with the clinical measures of visual function than did the VFQ total and subscale scores. Regression analysis revealed that binocular visual acuity, contrast sensitivity, and better eye visual field were the best predictors of ADREV performance. CONCLUSIONS: The ADREV performance measure is a valid instrument for the assessment of disability related to vision in patients with diabetic retinopathy. Furthermore, the assessments provided by ADREV were more related to traditional clinical indicators of visual impairment than were the results of the self-report measure, specifically the VFQ-25

Extended Slow Phase in Latent/Manifest Latent Nystagmus

PURPOSE. To investigate the slow phase in latent/manifest latent nystagmus (LMLN) by producing long eye-drift intervals devoid of fast phases (extended slow phases [ESPs]) and to relate ESP metrics to clinical findings. METHODS. Ten patients with LMLN had eye movements recorded while attending to paired visual and auditory cues presented to their left or right. Patients compared location of the visual target with that of the subsequently heard tone. The auditory cue and the comparison task directed attention away from vision and delayed the fast-phase onset to obtain ESPs. ESP metrics were analyzed with regard to patients' clinical characteristics. Five patients' data were further explored by isolating slow-phase components. RESULTS. All patients exhibited ESPs that resembled the usual slow phase but lasted two to three times longer. Five patients maintained alignment, whereas the other five made vergence movements. Greater eye velocity, excursion, and convergence during an ESP were associated with poor vision and large uncorrected esotropia. These metrics decreased when the viewing eye was in adduction, compared with primary position or abduction. Slow-phase components found in five patients consisted of a dominant decreasing-velocity or linear drift and a low-amplitude periodic oscillation. 1,3 It was suggested therefore that these two nystagmus types be combined into one entity, latent/manifest latent nystagmus (LMLN). CONCLUSIONS. Shifting attention away from vision reliably delays 6 Therefore, characterization of the slow phase is essential for understanding the ocular motor instability in nystagmus. Slow-phase duration is usually short because of its interruption by the fast phase. We searched for a way to modify nystagmus to obtain longer intervals of slow phase that could facilitate its investigation. It has been noticed that after the abolishment of the visual target in the dark the nystagmus cycle becomes less regular, and if a distracting mental task (such as performing mental arithmetic) is added to that, the onset of the fast phase can be delayed (Goldstein HP, et al. IOVS 1992;33: ARVO Abstract 2298-84; Gradstein L, et al. IOVS 1996;37:ARVO Abstract 1030)

Evolution of cyclophotocoagulation

Cyclodestructive techniques have been a treatment option for refractory glaucoma since its first use in the 1930s. Over the past nine decades, cyclodestruction has advanced from the initial cyclodiathermy to micropulse transscleral cyclophotocoagulation (MP-TSCPC) which is the current treatment available. Complications associated with cyclodestruction including pain, hyphema, vision loss, hypotony and phthisis have led ophthalmologists to shy away from these techniques when other glaucoma treatment options are available. Recent studies have shown encouraging clinical results with fewer complications following cyclophotocoagulation, contributing greatly to the current increase in the use of cyclophotocoagulation as primary treatment for glaucoma. We performed our literature search on Google Scholar Database, Pubmed, Web of Sciences and Cochrane Library databases published prior to September 2017 using keywords relevant to cyclodestruction, cyclophotocoagulation and treatment of refractory glaucoma

Structural Changes in Glaucoma: A Volumetric MRI Study

Purpose: To investigate brain structural changes in patients with glaucoma. Methods: High resolution 3D T1-weighted MP-RAGE MRI images were collected in 11 glaucoma patients (5 female, 6 male, 65+/-11 yrs), and 11 age- and gender-matched controls (64+/-12 yrs). The images were first analyzed using an automatic voxel-based morphometry technique which combines a fully automated spatial normalization approach, dubbed HAMMER [1], in conjunction with a tissue mass preserving framework called RAVENS [2]. Four consecutive steps were carried out: removal of non-brain voxels, tissue segmentation, spatial normalization to a standardized template, and generation of a mass-preserving tissue density map (i.e. RAVENS map) for each tissue type (GM, WM, ventricles). Measurements of volumes of individual brain structures: From the RAVENS maps of each individual subject’s brain, the HAMMER technique generated measurement of the sizes of 110 brain structures. These 93 structures were labeled in the template brain. Group comparison to identify structures that are different between groups in comparison: Unpaired t-test was carried out to identify structures that are significantly different between the two groups in comparison. Results: Table 1 listed structures that showed significant difference in volume. Interestingly, these structures are bigger in the glaucoma group than in the control group. In a companion study, a correlation analysis was carried out between the imaging results and clinical assessments for the interpretation and understanding of the findings. Conclusions: This study has reinforced the value of MRI as a robust tool to identify structural changes in the brain of glaucoma patients