This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Brain , Subject name: Anatomy
Which type of visual defects are caused by a tumour of the pituitary gland pressing upon the optic chiasma? 
Select and explain. 
A. Homonymous hemianopia, B. Heteronymous hemianopia, C. Bitemporal hemianopia, D. Binasal hemianopia
C: Bitemporal hemianopia
Answer: C: Bitemporal hemianopia 
Explanation: Damage to Central pa of optic chiasma (as may occur from pituitary tumours) interrupt the crossing fibres from nasal half of two retinae and results in bitemporal hemianopiasite and lesions are:Optic nerve- total blindnessOptic tract- homonymous hemianopiaVisual coex- macular sparingUpper tip of calcarine sulcus- contralateral Inferior quadrantanopiaLower lip of calcarine sulcus- C/L Superior quadrantanopia(Ref: Vishram Singh textbook of clinical neuroanatomy second edition pg 216)