Neuro-ophthalmologic exploration in non-functioning pituitary adenoma

Non-functioning pituitary adenoma may lead to blindness and causes visual impairment in 58% of cases and, more rarely, ocular motor disorder. Patients are slow to become aware of their visual dysfunction, vision in one eye compensating the deficit in the other. Assessment of visual function, comprising visual acuity and visual field evaluation and fundus examination, should be performed regularly according to the severity of impairment. Optic nerve optical coherence tomography (OCT) can quantify optic atrophy reproducibly, and is of prognostic value for postoperative visual recovery. Diplopia most often involves decompensation of heterophoria, visual field fusion being hampered by the visual field defect; such diplopia without ocular motor deficit is known as "hemifield slide". Diplopia associated with ocular motor palsy is caused by tumoral invasion of the cavernous sinus (IIIrd, IVth or VIth nerve palsy); in large impairment, restricted eye movement is easily observed; milder palsies require neuro-ophthalmologic assessment and/or Lancaster test. Pituitary apoplexy induces ocular motor impairment in 70% of cases, strongly guiding diagnosis. Visual impairment is associated in 75% of cases. The degree of neuro-ophthalmologic (visual and ocular motor) impairment is one of the main criteria guiding treatment of pituitary apoplexy (conservative medical and/or surgical treatment) and follow-up.