Visual Hallucinations (Charles Bonnet Syndrome) Associated with Neurosarcoidosis
A 46-year-old African American female presented in March 2010 with a 1-year history of bilateral progressive vision loss accompanied by right facial paresthesia in the V2 distribution, a right seventh-nerve palsy, eye pain, and photophobia. Over the next several weeks, the patient developed lucid visual hallucinations consisting mostly of an unfamiliar little girl. The images did not speak to the patient nor did she attempt to interact with the patient. The patient recognized that the hallucinations were not real and she was not disturbed or frightened by them. The hallucinations were not accompanied by any delusions, paranoid ideation, mental status changes, seizure activity or change in the level of consciousness. Past medical history was significant for a colonoscopy in 1990. The patient was not on any medications and denied the use of hallucinogens (i.e., anti-psychotics, barbiturates, sedatives, illicit drugs). The patient had been treated with topical antibiotic drops for her eye pain without relief. She had no prior psychiatric history.\nOn neuro-ophthalmic examination in March 2010, the patient was awake, oriented, and alert, but continued to complain of visual hallucinations. Best corrected visual acuity was 20/200 in both eyes. Pupils were 4.0 mm in the dark and 2.0 mm in the light with a left relative afferent pupillary defect and light-near dissociation in both eyes External examination revealed right partial peripheral facial nerve palsy. Motility and intraocular pressure exams were normal. Slit lamp bio-microscopy was normal without uveitis or granuloma formation. Dilated funduscopic examination showed bilateral optic nerve atrophy with temporal pallor in both eyes. Automated (Humphrey 24-2) visual fields revealed a cecocentral defect in the right eye and a central defect with superior arcuate nerve fiber layer defects in the left eye. Optical coherence tomography of the optic discs showed diffuse nerve fiber layer loss measuring 57 microns in the right eye and 70 microns in the left eye on the global indices.\nAngiotensin-converting enzyme levels were markedly elevated (<200 ug/L). A cranial magnetic resonance imaging study showed enhancement of both optic nerves [], both oculomotor nerves, the left V2 branch of the trigeminal nerve, and the right facial nerve as well as right cavernous sinus meningeal enhancement extending anteriorly and inferiorly into the pterygopalatine fossa, the orbital apex and the infratemporal fossa with minimal involvement of the occipital cortex. A full-body positron emission tomography scan and chest computed tomography scan revealed mediastinal lymphadenopathy as well as multifocal areas of hypermetabolic activity involving the head, neck, chest, abdomen, and pelvis with no evidence of occipital cortex involvement. Cerebrospinal fluid was significant for inflammatory pleocytosis (19 WBC's mm[], elevated protein, normal glucose). Mediastinal lymph node biopsy showed non-caseasting granulomas consistent with the diagnosis of sarcoidosis. The patient was started on 50 mg of prednisone daily for 3 months that was subsequently tapered to a maintenance dose of 5 mg.\nThe patient's visual hallucinations had completely resolved by September 2010. At last follow-up in April 2011, best visual acuity had improved to 20/25 bilaterally and the central visual field defects improved bilaterally with some residual mild nerve fiber layer defects and optic atrophy in both eyes. There was complete resolution of the patient's peripheral nerve palsy.