Capacity of Ring- and Light Sense Perimetry in the Topical Diagnosis of the Visual Pathway

Abstract

Ring perimetry is a novel method which determines peripheral resolution rather than differential light sensitivity (DLS). The authors investigated the capacity of ring perimetry in the topical diagnosis of neuro-ophthalmological lesions in comparison to that of DLS perimetry. Seventy-five patients with an established diagnosis of a single ophthalmological disorder were chosen for the study. They underwent a full clinical examination and both the ‘ring test’ with the ring perimeter Ophthimus (High-Tech-Vision Inc.) and the G1-program with the Octopus 1-2-3 (Interzeag Inc.). The main investigator who knew all clinical findings and the history ascribed each pair of visual fields to one of seven different topical diagnoses: (1) optic media, (2) retina, (3) optic disc, (4) optic nerve, (5) chiasm, (6) retrochiasmal pathway, and (7) normal. He selected five or six sample fields of each group and showed them to two experienced ophthalmologists. They had to assign the fields to one of the seven topical diagnoses. The whole test was repeated six weeks later. With ring perimetry 64%, and with DLS perimetry 65% of the assignments were correct. Hence, the efficacy of both methods was very similar, but the time needed for the ring perimetry (5.5 min) was about half that needed for the DLS perimetry (11.5 min).

Key Words:

• Ring perimetry
• light sense perimetry
• visual pathway
• topical diagnosis