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Previous Topic | Next Topic  absence of pupillary light reflex 




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Author2 Posts
  #1

what kind of midbrain lesion can cause loss of pupillary light reflex but intact accomodation reflex?? n how does it cause these signs??

thank you

  #2

Lesions at the pretectal region which is commonly affected by sphilis or diabetes.The path of accomodation reflex

Retina ---------> optic nerve and optic tract -----------> LGB -----------> occipital cortex ----------> Frontal eye field --------------> Edinger Westphal Nucleus ----------->occulomotor N

The path of Light reflex is

Retina --------------> optic N and optic tract -----------> pretectal N -----------> Edingerwestphal N--------> oculomotor N

Best of luck


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