Charles Bonnet syndrome after herpes simplex encephalitis

Visual hallucinations: A novel complication after hemispherectomy

Two patients at our center experienced florid visual hallucinations following hemispherectomy. The first patient had drug-resistant left hemispheric focal seizures at 20 months of age from a previous stroke. Following functional hemispherectomy at age 3, he experienced frightening hallucinations 1 month post-operatively lasting 3.5 months. Our second patient underwent subtotal hemispherectomy at age 6 for drug-resistant focal seizures from right hemispheric cortical dysplasia. Eighteen months later he developed scary visual hallucinations during which he would shout and throw things. Hallucinations recurred for 6 months. In our experience in these patients, even though symptoms were florid, they were transient and subsided 3–6 months later.

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Two patients had visual hallucinations after subtotal and functional hemispherectomy

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Hallucinations occurred over a 3–6 month period and then subsided.

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These may be due to deafferentation similar to Charles Bonnet syndrome.

Seeing the unseen: Charles Bonnet syndrome revisited

Charles Bonnet syndrome (CBS) is a rare condition that encompasses three clinical features: complex visual hallucinations, ocular pathology causing visual deterioration, and preserved cognitive status. Common associated ocular pathologies include age-related macular degeneration, glaucoma, and cataracts. Several theories have been proposed to try to explain the visual hallucinations. However, the pathophysiology remains poorly understood, and treatment is largely based on anecdotal data. The lack of awareness of CBS among medical professionals often leads to inappropriate diagnosis and medication. In a country like India, where awareness of mental health is not widespread, cultural myths and stigma prevent patients from seeking professional help. Here we describe two cases of CBS and revisit different ocular morbidities that have been reported to occur in conjunction with CBS. Psychiatrists and ophthalmologists alike must be sensitive to this clinical condition to ensure prompt diagnosis and treatment.