THE localization of intracranial mass lesions by means of hemianopsic defects has long been one of the standard methods used in neurologic diagnosis. The significance of macular "sparing," however, is still cause for controversy. Its presence or absence often serves to localize a lesion anywhere from the optic chiasm back to the calcarine cortex. The term macular "sparing" is a figurative one and has been used to include sparing of central vision varying from 2 to 10 degrees.1Thus, homonymous hemianopsia without sparing was believed to point to a lesion of the optic tract, whereas one with so-called macular sparing tended to indicate a lesion of the occipital lobe.2Homonymous quadrantic cuts are considered significant of lesions between the lateral geniculate body and the calcarine cortex, involving the optic radiation.3Since clinical evidence has shown that macular "sparing" may occur in the case of a large lesion