The influence of cortical, nuclear, subcortical posterior, and mixed cataract on the results of microperimetry

Abstract

Purpose Microperimetry is a useful instrument for evaluating sensitivity threshold due to retinal pathologies. The aim of the study is to assess the impact of different forms of cataract on microperimetry results. Methods In a prospective design, patients were recruited for cataract surgery at the Department of Ophthalmology, Medical University of Vienna. Exclusion criteria were any other ophthalmic disease except cataract, that is, macular pathology. Using the Lens Opacities Classification System III classification, patients were classified into four groups: nuclear, cortical, subcapsular posterior, and mixed cataract. Then patients underwent microperimetry: results were analyzed for magnitude of retinal sensitivity loss and correlated to the forms and density of the cataract. Results Mean density of cataract was LOCS 3.2-3.5 in the four groups. Differences were not statistically significant. The best-corrected visual acuity (BCVA) was LogMAR 0.5±0.13 in nuclear, LogMAR 0.49 ± 0.21 in cortical, and LogMAR 0.58 ± 0.12 in mixed cataract patients, and significantly worse in patients with subcapsular posterior cataract (LogMAR 0.64±0.12). Microperimetry shows a mean sensitivity of 11.4-12.6 dB without significant group differences. The BCVA is correlated with microperimetry in patients with nuclear and cortical cataract. Density of cataract is highly correlated with microperimetry results in all groups. Conclusion The present study shows a good correlation of microperimetry results with the BCVA of patients with nuclear and cortical cataract. In patients with subcapsular posterior cataract, microperimetry results were better than estimated by BCVA. Density of cataract is highly correlated with macular sensitivity. A reduction of 1 dB in microperimetry per 1 posterior capsule opacification score increase can be estimated for these patients.

Beneficial effects on vision in patients undergoing retinal gene therapy for choroideremia

“…29 Maintaining retinal sensitivity therefore requires successful transduction of the entire area being measured, right up to the edges of the surviving tissue and may also be reduced due to the development of cataract in treated eyes, which is known to impact on microperimetry more than visual acuity. 30 Among the adverse events (AE) encountered in the trial ( Supplementary Table S7), one incident of retinal stretch (C1) was clearly related to surgery. The other significant adverse event of inflammation (C2) might equally be related to surgery if significant vector reflux into the vitreous cavity occurred, which is known to trigger inflammation ( Supplementary Fig.…”

Two-Photon Microperimetry: A media opacity-independent retinal function assay

“…IR light is absorbed less by ocular media and therefore penetrates deeper into the eye than visible spectrum light. Traditional visual function tests suffer diminished reliability in patients with lenticular senescence and media opacities (6,13,14). Ruminski Conversely, 2PM is scotopic and the effect of brown filters was only significant for 2PM-Vis and not for 2PM-IR.…”

“…Cataractous lenses and posterior capsular opacification (14) also diminish retinal sensitivity measurements obtained using microperimetry. This decrease is dependent upon the density and type of cataract (6) formed.…”

“…VA testing is often performed using the Early Treatment Diabetic Retinopathy Study (ETDRS) or Snellen charts. However, VA is a poor predictor of total visual function (6), especially in patients with macular disease, as it provides no information on contrast sensitivity, color vision, nor metamorphopsia. Additional information for central visual function is available with cone contrast threshold (CCT) testing and microperimetry.…”

Short-Term Results of Intravitreal Triamcinolone Acetonide Combined with Cataract Surgery for Diabetic Macular Edema in Japan: In the Era of Anti-Vascular Endothelial Growth Factor Therapy

“…There is a possibility that these medications may have led to the reduction of the CRT after the IVTA treatment. And finally, because the retinal sensitivity may have also been affected by the cataract [21], our baseline retinal sensitivity values could have been underestimated, which affected the results. Thus, the retinal sensitivity was initially significantly improved at 4 and 12 weeks.…”