Dorsal midbrain (Parinaud's) syndrome is characterized by all EXCEPT:

• A Upgaze palsy
• B Light-near dissociation (pupils react to near but not to light)
• C Convergence-retraction nystagmus on attempted upgaze
• D Loss of downgaze with convergence spasm ✓

Explanation

Parinaud's syndrome (dorsal midbrain syndrome) classically involves: (1) upgaze paresis due to compression of the posterior commissure/rostral interstitial nucleus of MLF; (2) light-near dissociation — pupils respond to near (convergence-associated miosis via anterior Edinger-Westphal pathway) but not to light (posterior commissure lesion disrupts the reflex); (3) convergence-retraction nystagmus on attempted upgaze (co-contraction of horizontal rectus muscles); (4) eyelid retraction (Collier's sign). Loss of downgaze is not a feature of dorsal midbrain syndrome; it occurs with bilateral riMLF lesions or progressive supranuclear palsy.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.