Preferential Hyperacuity Perimeter (PHP) in Myopic CNV

PURPOSE: To analyze the hyperacuity defects of preferential hyperacuity perimeter (PHP) in myopic CNV and correlate with the other macular anatomical or physiological properties obtained with fluorescein angiography (FA), Optical coherence Tomography (OCT), and central perimeter. METHODS: Seven patients with myopic CNV diagnosed by FA underwent PHP, OCT, central visual field (VF). We examined the locational correlation among FA, central VF and PHP hyperacuity defect and then compared PHP hyperacuity defect with the CNV size by OCT. Also we made a comparison with macular sensitivity change in VF and hyperacuity defects change in PHP after PDT in 4 patients. RESULTS: All the 7 eyes with myopic CNV tested positive for hyperacuity defects. 5 eyes showed locational correlation among PHP and FA, central VF. The size of hyperacuity defect of PHP and CNV size by OCT was positive correlation (p=0.007). Four eyes treated with PDT showed decrease of PHP hyperacuity defect size and changes in location according to decrease of CNV size after PDT. CONCLUSIONS: Our results suggest that the PHP may be used to detect myopic CNV and beneficial for analyzing functional effect following PDT in myopic CNV patients. These results require further validation in a larger population.

Subretinal Hemorrhages in High Myopia

Ocular changes such as crescents, posterior staphyloma, retinochoroidal degeneration, lacquer cracks and subretinal or choroidal hemorrhage are common In myopia. We examined 13 patients(13 eyes) who had refractive errors of -6.0 Diopter or more and subretinal hemorrhages at initial visit. According to fluorescein angiographic finding, subretinal hemorrhages in high myopia were divided into two groups: 6 eyes without choroidal neovascularization(CNV) and 7 eyes with choroidal neovascularization. Subretinal hemorrhage without choroidal neovascularization was frequent in patients aged 15-32 years(mean, 23.7 years) and choroidal neovascularization was common in patients aged 34-60 years(mean 47.6 years). In the eyes without choroidal neovascularization, the subretinal hemorrhage disappeared spontaneously after a few months and the visual acuity of these patients was variable at the initial visit(range, 5/200-20/30), and was unchanged or improved during the follow-up period. In the eyes with choroidal neovascularization, the visual acuity was less than 0.1 at the initial visit, except 2 cases, and was unchanged or worsened during the follow-up peroid. It will be helpful to divide the high myopia with subretinal hemorrhage into with or without choroidal neovasculrization according to the flourescein angiography to assess the prognosis.