The missing temporal crescent.

PURPOSE

We studied clinically the representation of the monocular temporal crescent in the human visual cortex and noted the importance of using the perimetric techniques best suited to detect this visual field defect and to study patients in whom the temporal crescent is missing.

METHODS

Goldmann perimetry and high-resolution magnetic resonance imaging were performed in two patients with vascular lesions located in the anterior striate cortex.

RESULTS

A monocular visual field defect, the missing temporal crescent, was found on the side contralateral to the lesion.

CONCLUSIONS

The perimetric-magnetic resonance imaging correlation is in exquisite agreement with recent information about the representation of the visual field in the human primary visual cortex. Reports of this specific perimetric finding are rare, in part because of underdetection with currently used perimetric techniques that concentrate on the central 30 degrees of the visual field.