Visual Hallucinations in Patients with Macular Degeneration

Abstract

Objective: This study was undertaken to determine the prevalence of visual hallucinations in patients with macular degeneration, describe such hallucinations phenomenologically, and possibly determine factors predisposing to their development. Method: Using a case-control design, the authors screened 1 00 consecutive patients with age-related macular degeneration f or visual hallucinations. Each patient with visual hallucinations was matched to the next three patients without hallucinations. The patients and comparison subjects were compared in terms of scores on the Beck Depression Inventory, Eysenck Personality Questionnaire, Telephone Interview for Cognitive Status, and a structured questionnaire including demographic characteristics, family history, and medical and psychiatric history. Ophthalmologic data were obtained by chart review. Results: Of the I 00 patients, 1 3 experienced visual hallucinations. Four variables were significantly associated with having hallucinations: living alone, lower cognition score, history ofstroke, and bilaterally worse visual acuity. Hallucinations were not associated with family or personal history of psychiatric disorder or with personality traits. In 1 1 (84.6%) of the 13 patients, the hallucinations had begun in association with an acute change in vision. Conclusion: These results indicate that visual hallucinations are prevalent among patients with macular degeneration. They appear unrelated to primary psychiatric disorder. The predisposing factors of bilaterally worse vision and living alone support an association with sensory deprivation, while history of stroke and worse cognition support a decreased cortical inhibition theory. (Am J Psychiatry 1992; 149:1701-1706) V isual hallucinations are associated with a variety of lesions at all levels of the visual system (1-3). Weinbenger and Grant (2) reported visual hallucinations in patients with pituitary tumors pressing on the optic nerves and chiasm, noting that the hallucinations were not limited to the area of visual field loss. Lance (4) reported visual hallucinations in patients with homonymous field defects and noted that the hallucinations were confined to the area of visual field loss in all but one patient. Because the calcanine area of the occipital lobe was infarcted in many of these patients, he concluded that it was not the origin of the hallucinations and suggested that the surrounding visual association cortex was. Kolmel (5) reported that 13% of 120 patients with homonymous hemianopia and occipital lobe damage experienced complex visual hallucinations in the hemianopic field. The subjects