The localizing value of a quadrantanopia
D. M. Jacobson
Department of Neurology, Marshfield Clinic, Wis., USA. jacobsod@mfldclin.edu
BACKGROUND: A lesion affecting the optic radiations may produce a
quadrantanopia based on the topographical arrangement of the
geniculocalcarine tract. OBJECTIVE: To determine the localizing
associations of a quadrantic visual field defect. DESIGN: Retrospective
study of case records of 41 patients with inferior quadrantanopia and 30
patients with superior quadrantanopia caused by disorders affecting the
posterior visual pathway. The responsible lesion was identified with
neuroimaging techniques. SETTING: Neuro-ophthalmology referral practice in
a large multispecialty clinic that provides primary, secondary, and
tertiary medical care. RESULTS: Cerebrovascular disorders accounted for
most lesions. The location (and frequency) of lesions causing inferior
quadrantanopia was occipital lobe (76%), parietal lobe (22%), and temporal
lobe (2%). Other localizing signs were associated with 6%, 89%, and 0% of
lesions located in the occipital, parietal, and temporal lobes,
respectively. The location (and frequency) of lesions causing superior
quadrantanopias was occipital lobe (83%), parietal lobe (3%), and temporal
lobe (13%). Other localizing signs were associated with 4%, 100%, and 0% of
lesions located in the occipital, parietal, and temporal lobes,
respectively. CONCLUSIONS: A patient with a neurologically isolated
quadrantanopia is likely to have a lesion in the occipital lobe, although,
in the case of a superior quadrantanopia, the possibility of a temporal
lobe lesion can not be excluded using clinical criteria only.
Quadrantanopias caused by lesions of the parietal lobe usually are
associated with other localizing signs.
