0816 Chronic insomnia secondary to severe nocturnal visual hallucinations in Charles Bonnet syndrome; a challenging case to manage
Authors: Barber Cameron , Glidewell Robert , Carroll Dylan , Aylor-Lee Kourtney 
Published: May 2022

Introduction

Over 1 million Americans are blind. Charles Bonnet syndrome (CBS), a parallel to phantom limb syndrome and also known as release hallucinations, describes visual hallucinations in patients with severe visual loss and blindness. The prevalence of release hallucinations, though likely underreported, is believed to be 12 to 20% of visually impaired persons.

Report of Cases: A 45-year-old male with past medical history of migraines presented to the hospital with what was determined to be a ruptured pituitary macroadenoma and as a result, lost complete visual function including pupillary reflexes. The patient subsequently experienced both simple and complex release hallucinations and was eventually diagnosed with Charles Bonnet syndrome. Most disturbing to the patient was the simple release hallucinations which was described as a bright white light in a honeycomb lattice predominately in his right visual field which lasted for hours. This phantom light was not consistently associated with any other symptoms and could occur at any time throughout the 24-hour day. Nocturnal symptoms occurred approximately 50% of nights and caused severe onset/maintenance insomnia and insufficient sleep duration. The patient tried therapy in addition to proper sleep hygiene without relief. He was trialed on several medications and the only one able to alleviate all but the worst of the phantom light was diazepam. The GABA-A receptor agonist finally allowed the patient an opportunity to sleep. His insomnia was then treated with once nightly temazepam, in addition to as needed diazepam. Approximately nine years after losing his vision, he was transitioned from

temazepam to the tricyclic antidepressant amitriptyline, which offered improved relief from the phantom lights causing his insomnia. The patient continues to utilize once nightly amitriptyline with diazepam for breakthrough symptoms, though he still suffers significant impairment due to the phantom lights of his Charles Bonnet syndrome.

Conclusion

Treatment of Charles Bonnet syndrome is multifactorial and includes maintaining optimal eye care, stimulating senses, psychosocial therapy, and pharmacotherapy. Insomnia from release hallucinations remains difficult to manage, though GABA-A receptor agonists have shown some relief. Case reports of atypical antipsychotics and antidepressants, including melperone and agomelatine respectively, have demonstrated ability to improve release hallucinations.

Support (If Any)

Charles Bonnet Syndrome FAQs. Charles Bonnet Syndrome Foundation (Australia). https://www.charlesbonnetsyndrome.org/index.php/cbs/faq. Accessed December 15, 2021.Hsu HC, Huang YS, Fan WX, Chen TC. Charles Bonnet Syndrome (CBS): Successful Treatment of Visual Hallucinations Due to Vision Loss with Agomelatine in Three Cases. European Psychiatry. 2017;41(S1):S172-S172. doi:10.1016/j.eurpsy.2017.01.2065Pelak VS. Visual release hallucinations (Charles Bonnet syndrome). UpToDate. Waltham, MA: UpToDate; June 7, 2016; https://www.uptodate.com/contents/visual-release-hallucinations-charles-bonnet-syndrome.