Tuesday 17 November 2015

Inability to abduct left eye with LMN fascial palsy on same side | Medical PG Preparations

Inability to abduct left eye with LMN fascial palsy on same side. The lesion is in 

A. Left pons 
B. Right pons
C. CP angle tumor 
D. Cerebellar lesions

Ans. A. Left pons 
° Theabducentnucleus is present in the pons along with facial nucleus and both are damaged here.


o These nuclei contain the lower motor neurons and hence the lesion here gives ipsilateral signs 
o Hence, the lesion in the left pons leads to left facial palsyand inability to abduct the left eye laterally - 
o The pons is a structure located on the brain stem. 
o It is above the medulla, below the midbrain, and anterior to the cerebellum. 
o The posterior back.  surface of the pons forms part of the floor of the fourth ventricle of the brain.