Sparing of the pupil with paralysis of the third cranial nerve has been reported to be characteristic of diabetic ophthalmoplegia.1,2 This has been borne out by a number of case reports.3-5 In a large series of oculomotor paralyses, Rucker6 found that 18 of 21 diabetics showed sparing of the pupil. The one histopathologic study of diabetic third nerve paralysis (Dreyfus, Hakim, and Adams7) suggested that the normal pupillary reactions were due to sparing of the circumferential portion of the third nerve.
It is the purpose of this paper to report the pupillary findings in our cases of diabetic ophthalmoplegia and to make a spot check of pupillary reactivity in third nerve paralysis unassociated with diabetes. An attempt has also been made to define the characteristics of diabetic third nerve paralysis as seen in our cases. The diagnosis of diabetes mellitus was made either by overt disease
GOLDSTEIN JE, COGAN DG. Diabetic Ophthalmoplegia with Special Reference to the Pupil. Arch Ophthalmol. 1960;64(4):592-600. doi:10.1001/archopht.1960.01840010594018