Disc excavation in dominant optic atrophy: differentiation from normal tension glaucoma.

OBJECTIVE

In patients with dominant optic atrophy (DOA, Kjer type), excavation of the optic nerve develops, and these patients may be misdiagnosed as having normal tension glaucoma (NTG). This study examined disc morphologic features in patients with DOA and explored features that help distinguish this condition from NTG.

DESIGN

Noncomparative, observational case series.

PARTICIPANTS

Patients with DOA who were seen at the Duke University Eye Center between 1987 and 1996 and who had bilateral optic nerve photographs.

METHODS

Retrospective chart review of the results of visual acuity testing, visual field testing by Goldmann perimetry, color vision testing, intraocular pressure measurement, and observation of bilateral optic nerve photographs.

MAIN OUTCOME MEASURES: Appearance of the optic disc and peripapillary zone in patients with DOA.

RESULTS

Nine patients were identified. The mean age at the time of evaluation was 28 years (range, 11-62 years). Most patients had a mild to moderate reduction in visual acuity. Color vision as tested with Hardy-Rand-Rittler plates was reduced (4.0/10 +/- 4.2/10). A cup-to-disc ratio of more than 0.5 was observed in at least one eye of eight patients. A temporal wedge-shaped area of excavation was observed in 14 of the 18 eyes studied. Moderate to severe temporal pallor was observed in all of the eyes. Pallor of the remaining (noncupped) neuroretinal rim was also observed consistently, ranging from mild to moderate. A gray crescent and some degree of peripapillary atrophy were noted in all eyes.

CONCLUSIONS

Several clinical features, including early age of onset, preferential loss of central vision, sparing of the peripheral fields, pallor of the remaining neuroretinal rim, and a family history of unexplained visual loss or optic atrophy, help to distinguish patients with DOA from those with NTG.