Neuroopthalmic findings that reliably differentiate PSP and PD

P05.042 AAN book 2008 Brad Katz et al. Salt Lake City Utah

In addition to standard criteria , the following differentiated the 2 disorders: slowed horizontal saccades, square wave jerks, eyelid opening apraxia, abnormal vertical OKN's, lid retraction stare, blink rate and light sensitivity were all implicated. A cutoff score of 2 or more of the the following three features: greater than 5 swj's, abnormal OKN's downward, and lid retraction stare identified all of 28 patients correctly (including placebos).

Hardwick A, Rucker JC, Cohen ML, et al.  Evolution of oculomotor and clinical findings in autopsy proven Richardson syndrome.  Neurology 73; 2122-2123 2009.

Authors note the SPEED of vertical saccades (more than amplitude) remain the cornerstone for differentiating PSP from other disorders.  Clinical presentation was young, absent falls, complaints of horizontal diplopia due to vergence abnormalities, cognition c/w FTD.  At autopsy atrophy was restricted to the superior colliculi with rare NFTs.