Lesion of the optic chiasma result in bitemporal hemianopia not homonymous hemianopia. Lesions of the visual pathway and corresponding field defects: Lesion of optic nerve: Ipsilateral blindness Lesion through proximal pa of optic nerve: Ipsilateral blindness with contralateral quadrantanopia. Lesion of optic tract: Homonymous hemianopia Lesion of temporal lobe: Quadrantic homonymous defect Lesion of optic radiation: Homonymous hemianopia with occasional sparing of the macula Lesion in anterior pa of occipital coex: Contralateral temporal crescentic field defect Lesion of occipital lobe: homonymous hemianopia usually sparing of the macula Ref: Textbook of Ophthalmology By H. V. Nema, page 340