- black patch delirium
- Also known as black patch psychosis, black patch syndrome, black patch disease, and cataract delirium. The term black patch delirium was introduced in 1958 by the American philosopher, psychiatrist, and thanatologist Avery D. Weisman (b. 1914?), and his colleague Thomas Paul Hack-ett, Jr. (1928-1988) to denote an acute confu-sional state dominated by * complex visual hallucinations in individuals wearing a bilateral eye patch following cataract surgery. Although different in name, similar hallucinatory and delirious states occurring after cataract surgery have been described since around 1900. As far as the visual hallucinations are concerned, black patch delirium appears to display a certain phenomeno-logical overlap with * Charles Bonnet syndrome.However, the two syndromes would seem to differ with respect to the presence of additional psychotic or delirious symptoms concomitant to black patch delirium, and the absence of any such additional signs or symptoms in Charles Bonnet syndrome. Pathophysiologically, the hallucinations occurring in the context of black patch deliriumtendtoberegardedas* deafferentiation phenomena or * perceptual release phenomena comparable to the hallucinations occurring in the context of * sensory deprivation. Etiologically, ample attention has also been drawn to the possible influence of toxic substances such as anaesthetics, therapeutics, illicit drugs, and alcohol, to co-morbid disorders, and to psychological mechanisms such as homesickness, feelings of distress, and feelings of vulnerability. The nosological status of black patch delirium has been contested by some authors on the grounds that, in a phe-nomenological and pathophysiological sense, it does not seem to differ from * delirium proper or from senile forms of *psychosis. Today the term black patch delirium is used only infrequently in the literature. As today's state-of-the-art postoperative care of cataract patients is directed at the prevention of delirium, it may well be that the true incidence of disorders formerly designated as black patch delirium is also somewhat on the wane.ReferencesJackson, C.W. (1969). Clinical sensory deprivation: A review of hospitalized eye-surgery patients. In: Sensory deprivation: Fifteen years of research. Edited by Zubek, J.P. New York, NY: Appleton-Century-Crofts.Rabins, P.V. (1991). Psychosocial and management aspects of delirium. International Psy-chogeriatrics, 3, 319-324.Weisman, A.D., Hackett, T.P. (1958). Psychosis after eye surgery. New England Journal of Medicine, 258, 1284-1289.
Dictionary of Hallucinations. J.D. Blom. 2010.