TRIGEMINAL SENSORY LOSS IN ORBITAL DISEASE

A study was undertaken to estimate the incidence of periorbital trigem inal sensory loss with different types of orbital disease and to deter mine whether the area of loss is related to the location or nature of the underlying condition. A retrospective review was carried out of th e clinical case notes of patients identified from the orbital diagnost ic database held at Moorfields Eye Hospital. A total of 103 patients ( 51 male, 52 female), aged between 11 and 84 years (median 51 years), h ad signs of periorbital trigeminal sensory loss at the time of investi gation for orbital disease and in 14/103 (13%) this sensory loss was s ymptomatic. Sensory loss was due to trauma in eight cases (8%), benign orbital disease in 54 (52%), and malignant disease in 41 cases (40%). The relative frequency of recorded sensory changes is about 9% for ma lignant tumours, 5% for benign tumours, 4% after orbital trauma, 3% fo r orbital inflammatory disease, and less than 1% for orbital structura l anomalies. Relative corneal hypoaesthesia occurred in 40/103 (39%) c ases. Periorbital sensory loss was recorded in about 3% of patients wi th orbital disease and, in contrast with commonly held views, malignan cy was not the most common cause of sensory loss. The affected dermato me is a useful guide to the location of orbital disease, but a poor in dication of underlying pathology. Relative corneal hypoaesthesia appea rs un-related to the type of disease or to its location within the orb it.