Temperature – A Contributing Factor in a Case of Superior Oblique Palsy

Kirsty Somerville McAlester, BMedSci(Orthoptics)Hons
Julia Kelly, DOBA MHSM
Orthoptic Department, Sydney Hospital & Sydney Eye Hospital, Sydney, Australia

An unusual case of superior oblique palsy with vertical diplopia, exacerbated by temperature change is presented. The presenting symptoms raised suspicion of a clinical condition akin to that of “Uhthoff’s Phenomenon” as seen in multiple sclerosis, however, the increased temperature in this patient led to diplopia not vision impairment. The clinical signs are presented, together with the investigations which were undertaken in order to determine whether the suspected diagnosis of Ocular Myasthenia Gravis (OMG) could be confirmed. The clinical findings are examined in light of current evidence regarding diagnostic tests for OMG. Special attention is given to the ‘Ice Test’, a simple clinical test that aids in the diagnosis of OMG.