Crossed-quadrant homonymous hemianopsia. The "checkerboard" field defect.

A 70-year-old man with a history of hypertension and coronary artery disease suffered an abrupt loss of vision in June 1980. Neuro-ophthalmologic examination in August 1981 revealed 20/20+ acuity in both eyes, but quantitative perimetry disclosed a classic crossed-quadrant homonymous hemianopsia. This is known as the "checkerboard" visual field defect; a right upper quadrantanopsia as well as a left lower quadrantanopsia. A review of the eight previously reported cases is presented. A trial with "checkerboard" Fresnel prisms gave only a slight improvement in ambient field in this patient. The significance of that point is discussed. To our knowledge, this is the first patient with a "checkerboard" occipital lobe infarction pattern documented by computed tomography.