Abstract
Purpose: :
To compare sensitivity and specificity of scotoma detection by preferential hyperacuity perimeter (PHP) to Amsler grid in dry and wet age-related macular degeneration (ARMD), diabetic macular edema (DME) and idiopathic polypoidal choroidal vasculopathy (IPCV)
Methods: :
This is a prospective single-blinded study of patients with various macular pathologies including dry ARMD, wet ARMD, DME and IPCV at Veterans Affairs Boston Healthcare System, Jamaica Plain, MA. Twenty-two eyes of twelve patients underwent full ophthalmic examination including visual acuity, anterior segment and dilated fundoscopic examiantion. Before dilation, Amsler grid and PHP were tested in each individual. Control group consisted of healthy subjects without any retinal pathology. Healthy objects also underwent full ophthalmic examination in addition to taking Amsler grid and PHP. Two-tailed z-test with 95% confidence interval was used to calculate p-values.
Results: :
The study population consisted of 40% dry ARMD, 40% wet ARMD, 10% DME and 10% IPCV. The average age of study population was 82 with 64% having hypertension (HTN) and 23% with diabetes (DM). The average logMAR acuity for the study population was 0.364 (Snellen equivalent of: 20/46). Average age of control group was 28 with an average logMAR acuity of -0.087 (Snellen equivalent of: 20/16.53). None of the healthy subjects had HTN or DM. Sensitivity of PHP in detecting scotoma compared to Asmler was as follow: wet ARMD: 77% versus 55% (z-value: 0.5); dry ARMD: 55% versus 22% (z-value 0.967); DME: 100% versus 50% (z-value: 0.816) and IPCV: 50% versus 50% (z-value: -0.707). Specificity of PHP versus Amsler was as 90%.
Conclusions: :
Early detection of scotoma is a critical step in recognition of macular pathology. In diseases such as ARMD, an early scotoma can signal conversion of dry form to a wet form. Amsler grid has been a conventional method thus far for detection of such scotoma. In this study we tested potential of PHP in early detection of scotoma. Although there was a trend for PHP being a more sensitive test, there was no significant difference between PHP and Amsler in scotoma detection. A larger study population is needed to further investigate PHP device.
Keywords: age-related macular degeneration • diabetic retinopathy • retina