Unilateral Proptosis of Unexplained Origin: Report of Nine Cases.

REESE (1951) and other authors hold that, except when an orbital tumour is palpable, no surgery should be attempted unless a deep orbital tumour affects the function of the eye or the optic nerve. Reese recalled no case in which the orbit had been explored with benefit, merely because of an unexplained unilateral proptosis. Among my series of 130 cases of unilateral proptosis, mostly caused by primary orbital tumours, there were nine in which the cause of the proptosis remained unknown. To leave such cases undiagnosed until an orbital tumour becomes palpable is a worry to both patient and ophthalmologist. The cause may be a malignant tumour, which may infiltrate the orbital tissues and give rise to metastasis. Even if the cause is a simple tumour or cyst, it is better to remove it while it is small and not yet firmly adherent to the orbital structures, and before it causes severe proptosis with the danger of corneal ulceration or presses on the optic nerve or ocular nerves causing visual deterioration and ophthalmoplegia.