High myopia pinpointed as risk factor for significant visual field defect progression

Am J Ophthalmol. 2011;152(2):256-265.

High myopia may be a prevalent risk factor for visual field defects, a study found.

“Because of the high incidence of visual field defects and the progression of the visual field defects, we suggest that high myopia be considered a high-risk group of visual field defects and should be monitored at least yearly,” the study authors said.

The retrospective study included 492 eyes of 308 patients with myopic refractive error greater than 8 D or axial length of 26.5 mm or greater. Mean patient age was 40.6 years. Mean follow-up was 11.6 years.

Significant visual field defects were defined as loss of 10% or more of 100 sectors within the V4 isopter. Significant progression of visual field loss was defined as further loss of 10% or more.

Study results showed that 65 eyes of 44 patients (13.2%) developed significant visual field loss.

“Significant visual field defects were detected in the superior temporal field in 52 eyes, in the inferior temporal field in 42 eyes, in the superior nasal field in 42 eyes and in the inferior nasal field in 37 eyes,” the authors said.

Visual field change was identified in two quadrants in one eye, three quadrants in 13 eyes and four quadrants in 33 eyes.

All 44 patients received antiglaucoma medication after the development of significant visual field defects.

“An abrupt change of the scleral curvature … was the only factor significantly associated with a progression of the [visual field] defects,” the authors said. “Visual field defects in the highly myopic eyes most likely were not caused by the same mechanisms that caused the visual field defects in eyes with glaucoma.”