Pupillary changes attributed to intracisternal papaverine injection were observed in three patients who underwent pterional craniotomy and clipping of a supratentorial aneurysm in which the oculomotor nerve was not manipulated. A fixed and dilated pupil on the side of the craniotomy lasted 2 to 4 hours after intracisternal papaverine instillation. These observations suggest that a dilated, nonreactive pupil subsequent to an uncomplicated pterional craniotomy for aneurysm, in which oculomotor nerve trauma has not occurred, may not be an ominous finding but may represent a transient phenomenon related to intracisternal papaverine injection.