Abstract
Early diagnosis of sphenoidal sinus mucocoeles presenting with visual loss is important as appropriately timed surgical intervention may improve the visual deficit. Two cases of sphenoidal sinus mucocoeles presenting with visual symptoms are reported in whom the diagnosis was only established at a late stage. A third case thought on clinical and radiological grounds to have a sphenoidal sinus mucocoele causing visual symptoms was found to have a frontal astrocytic glioma eroding through the ethmoidal sinus. These case reports stress that the definitive diagnosis in cases of sphenoidal sinus mucocoele is often delayed and that the pre-operative distinction between sphenoethmoidal sinus mucocoeles and other lesions involving the spheno-ethmoidal region may not always be possible.