This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Neuro-ophthalmology, Subject name: Ophthalmology
Wernicke&;s hemianopic pupillary reaction indicates lesions at the level of 
Select and explain. 
A. Distal pa of optic nerve, B. Optic tract, C. Optic chiasma, D. Optic radiation
B: Optic tract
Answer: B: Optic tract 
Explanation: Lesions of optic tract: These are characterised by incongruous homonymous hemianopia associated with contralateral hemianopic pupillary reaction (Wernicke's reaction). These lesions usually lead to paial descending optic atrophy and may be associated with contralateral third nerve paralysis and ipsilateral hemiplegia. Common causes of optic tract lesions: Include syphilitic meningitis or gumma, tuberculosis and tumours of optic thalamus and aneurysms of superior cerebellar or posterior cerebral aeries. Ref:- A K KHURANA; pg num:-290