Visual field loss in pituitary and hypothalamic disorders

Pituitary and hypothalamic tumours and disorders cause visual impairment due to proximity to structures critical for vision: intracranial optic nerves, chiasm and optic tracts. Visual dysfunction arising from compression of these structures typically has a profound impact upon quality of life. Visual fields should not be interpreted in isolation but in the context of a complete neuro-ophthalmic evaluation. Optical coherence tomography (OCT), specifically peripapillary retinal nerve fibre layer (pRNFL) and macular ganglion cell layer (mGCL), quantifies the degree of structural damage of the anterior visual pathway and optic chiasm. OCT changes may precede the onset of visual field changes in asymptomatic patients with chronic compression of the optic nerve or chiasm, and also have a prognostic role for predicting the recovery in visual function following surgery. This review focuses on an overview of the impact of pituitary and hypothalamic disorders, namely pituitary adenomas, macroprolactinomas, pituitary apoplexy, craniopharyngiomas, rathke cleft cysts, optic pathway gliomas, suprasellar meningiomas, hypophysitis and inflammatory disease on visual fields and function. The impact of interventions such as medical therapy, surgery and radiotherapy, as well as the adverse outcomes upon the visual function are also discussed. We highlight the key role of the neuro-ophthalmologist, within the multidisciplinary team, in the diagnosis and monitoring of these patients.