The pituitary gland serves an essential role in the activity and regulation of the endocrine system. Mass lesions within the pituitary gland account for approximately 10–15% of intracranial neoplasms. Patients with pituitary adenomas may present with endocrine dysfunction or neuro-ophthalmic pathology, resulting from compression of surrounding structures, most notably the optic chiasm. Visual deficits from chiasmal tumors may manifest as visual field defects, visual loss, diplopia, nystagmus and visual hallucinations. Visual field defects are the most commonly reported presenting visual symptom. The specific visual field defect usually results from the anatomic compression of the tumor upon the optic chiasm. It is important to recognize characteristic visual deficits in the diagnosis and treatment of chiasmal tumors.