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| | {{DISPLAYTITLE:Visual Release Hallucinations}} |
| | {{Infobox medical condition |
| | | name = Visual Release Hallucinations |
| | | image = |
| | | caption = |
| | | field = [[Ophthalmology]], [[Neurology]] |
| | | symptoms = Visual hallucinations |
| | | causes = [[Vision loss]], [[Charles Bonnet syndrome]] |
| | | diagnosis = Clinical evaluation |
| | | treatment = Reassurance, [[vision rehabilitation]] |
| | }} |
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| '''Visual release hallucinations''', also known as '''Charles Bonnet syndrome''' or '''CBS''', are a type of psychophysical visual disturbance and the experience of complex visual [[hallucination]]s in a person with partial or severe [[blindness]]. | | ==Overview== |
| | '''Visual release hallucinations''' are a phenomenon where individuals experience [[visual hallucinations]] due to a lack of visual input, often associated with significant [[vision loss]]. These hallucinations are typically non-threatening and are most commonly seen in patients with [[Charles Bonnet syndrome]]. |
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| First described by [[Charles Bonnet]] in 1760,<ref>{{cite journal |last1=de Morsier |first1=G |year=1967 |title=Le syndrome de Charles Bonnet: hallucinations visuelles des vieillards sans deficience mentale |trans-title=Charles Bonnet syndrome: visual hallucinations of the elderly without mental impairment |language=French |journal=Ann. Méd.-Psychol. |volume=125 |pages=677–701 }}</ref><ref name="Vukicevic/Fitzmaurice">{{cite journal |doi=10.1111/j.1442-9071.2008.01814.x |pmid=18983551 |title=Butterflies and black lacy patterns: The prevalence and characteristics of Charles Bonnet hallucinations in an Australian population |journal=Clinical & Experimental Ophthalmology |volume=36 |issue=7 |pages=659–65 |year=2008 |last1=Vukicevic |first1=Meri |last2=Fitzmaurice |first2=Kerry }}</ref> the term ''Charles Bonnet syndrome'' was first introduced into English-speaking [[psychiatry]] in 1982.<ref>{{cite journal |doi=10.1093/ageing/11.1.17 |pmid=7041567 |title=The Charles Bonnet Syndrome and the Problem of Visual Perceptual Disorders in the Elderly |journal=Age and Ageing |volume=11 |issue=1 |pages=17–23 |year=1982 |last1=Berrios |first1=German E. |last2=Brook |first2=Peter }}</ref> A related type of hallucination that also occurs with lack of visual input is the [[closed-eye hallucination]].
| | ==Etiology== |
| | Visual release hallucinations occur when there is a significant reduction in visual input to the brain. This can be due to various causes of vision loss, such as [[macular degeneration]], [[glaucoma]], or [[cataracts]]. The brain, deprived of normal visual stimuli, may generate its own images, leading to hallucinations. |
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| ==Signs and symptoms== | | ==Pathophysiology== |
| People with significant [[vision loss]] may have vivid recurrent visual hallucinations (fictive visual percepts).<ref name=":1" /> One characteristic of these hallucinations is that they usually are "[[Alice in Wonderland syndrome|lilliputian]]" (hallucinations in which the characters or objects are smaller than normal).<ref>{{Cite journal|last=Vojniković|first=Bozo|last2=Radeljak|first2=Sanja|last3=Dessardo|first3=Sandro|last4=Zarković-Palijan|first4=Tija|last5=Bajek|first5=Goran|last6=Linsak|first6=Zeljko|date=2010|title=What associates Charles Bonnet syndrome with age-related macular degeneration?|url=https://pubmed.ncbi.nlm.nih.gov/21305724/|journal=Collegium Antropologicum|volume=34 Suppl 2|pages=45–48|issn=0350-6134|pmid=21305724|via=}}</ref> Depending on the content, visual hallucinations can be classified as either simple or complex.<ref name=":1" /> Simple visual hallucinations are commonly characterized by shapes, [[Photopsia|photopsias]] and grid-like patterns.<ref name=":0">{{Cite journal|last=Pang|first=Linda|date=2016|title=Hallucinations Experienced by Visually Impaired: Charles Bonnet Syndrome|url=https://journals.lww.com/optvissci/FullText/2016/12000/Hallucinations_Experienced_by_Visually_Impaired_.4.aspx#O7-4-3|journal=Optometry and Vision Science|language=en-US|volume=93|issue=12|pages=1466–1478|doi=10.1097/OPX.0000000000000959|issn=1538-9235|via=|pmc=5131689}}</ref> On the other hand, complex visual hallucinations consist of highly detailed representations of people and objects.<ref name=":0" /> The most common hallucination is of faces or cartoons.<ref name="ted">{{cite web|author=TED2009|title=Oliver Sacks: What hallucination reveals about our minds | Video on|url=http://www.ted.com/talks/oliver_sacks_what_hallucination_reveals_about_our_minds.html|url-status=live|archiveurl=https://web.archive.org/web/20130708194612/http://www.ted.com/talks/oliver_sacks_what_hallucination_reveals_about_our_minds.html|archivedate=2013-07-08|accessdate=2013-07-03|publisher=Ted.com}}</ref> Sufferers [[Pseudohallucination|understand that the hallucinations are not real]], and the hallucinations are only visual, that is, they do not occur in any other senses, e.g. hearing, smell or taste.<ref>{{cite journal |pmid=1816537 |year=1991 |last1=Schultz |first1=G |title=The Charles Bonnet syndrome: 'phantom visual images' |journal=Perception |volume=20 |issue=6 |pages=809–25 |last2=Melzack |first2=R |doi=10.1068/p200809}}</ref><ref name="Mogk/Riddering/Dahl/Bruce/Brafford">{{cite book |first1=Lylas G. |last1=Mogk |first2=Anne |last2=Riddering |first3=David |last3=Dahl |first4=Cathy |last4=Bruce |first5=Shannon |last5=Brafford |chapter=Charles Bonnet Syndrome In Adults with Visual Impairments from Age-Related Macular Degeneration |chapterurl={{Google books|mve0LPp6_pUC|page=117|plainurl=yes}} |pages=117–9 |editor1-first=Aries |editor1-last=Arditi |editor2-first=Amy |editor2-last=Horowitz |editor3-first=Mary Ann |editor3-last=Lang |editor4-first=Bruce |editor4-last=Rosenthal |editor5-first=Karen |editor5-last=Seidman |editor6-first=Cynthia |editor6-last=Stuen |year=2000 |title=Vision Rehabilitation |isbn=978-90-265-1631-3 }}</ref> Visual hallucinations generally appear when the eyes are open, fading once the visual gaze shifts.<ref name=":1" /> It is widely claimed that sensory deprivation is instrumental in the progression of CBS.<ref name=":2" /> During episodes of inactivity, hallucinations are more likely to occur.<ref name=":1" /> Majority of those suffering from CBS describe the duration of hallucinations to continue for up to a few minutes, multiple times a day or week.<ref name=":1" />
| | The exact mechanism of visual release hallucinations is not fully understood, but it is believed to involve the [[visual cortex]] of the brain. When visual input is reduced or absent, the visual cortex may become hyperactive or "release" stored images, resulting in hallucinations. This is thought to be a compensatory mechanism of the brain to fill in the gaps of missing visual information. |
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| Even though people of all ages may be impacted by Charles Bonnet Syndrome, those within the age range of 70 to 80 are primarily affected.<ref name=":1" /> Among older adults (> 65 years) with significant vision loss, the prevalence of Charles Bonnet syndrome has been reported to be between 10% and 40%; a 2008 Australian study found the prevalence to be 17.5%.<ref name="Vukicevic/Fitzmaurice" /> Two Asian studies, however, report a much lower prevalence.<ref>{{cite journal |doi=10.1136/bjo.2004.041947 |pmid=15377560 |pmc=1772345 |title=Charles Bonnet syndrome in Asian patients in a tertiary ophthalmic centre |journal=British Journal of Ophthalmology |volume=88 |issue=10 |pages=1325–9 |year=2004 |last1=Tan |first1=C S H |last2=Lim |first2=V. S. |last3=Ho |first3=D. Y. |last4=Yeo |first4=E |last5=Ng |first5=B. Y. |last6=Au Eong |first6=K. G. }}</ref><ref>{{cite journal |doi=10.1167/iovs.06-0942 |pmid=17325191 |title=Visual Loss and Visual Hallucinations in Patients with Age-Related Macular Degeneration (Charles Bonnet Syndrome) |journal=Investigative Ophthalmology & Visual Science |volume=48 |issue=3 |pages=1416–23 |year=2007 |last1=Abbott |first1=Emily J. |last2=Connor |first2=Gillian B. |last3=Artes |first3=Paul H. |last4=Abadi |first4=Richard V. |doi-access=free }}</ref> The high incidence of underreporting this disorder is the greatest hindrance to determining the exact prevalence.<ref name="Mogk/Riddering/Dahl/Bruce/Brafford" /> Underreporting is thought to be a result of sufferers being afraid to discuss the symptoms out of fear that they will be labeled of unsound mind.<ref name="Mogk/Riddering/Dahl/Bruce/Brafford" />
| | ==Clinical Presentation== |
| | Patients with visual release hallucinations often report seeing complex images such as people, animals, or intricate patterns. These hallucinations are usually vivid and detailed but are recognized by the patient as not being real. Unlike hallucinations associated with psychiatric disorders, these are not accompanied by other sensory or cognitive disturbances. |
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| == Pathophysiology == | | ==Diagnosis== |
| [[File:Lawrence 1960 9.7.png|thumb|Anatomical illustration of human neuroanatomy]]
| | Diagnosis of visual release hallucinations is primarily clinical. A thorough [[medical history]] and [[physical examination]] are essential. It is important to differentiate these hallucinations from those caused by psychiatric conditions or [[neurological disorders]]. |
| There is no general consensus on the definition of CBS.<ref name=":0" /> Predominant factors correlated with CBS are a decrease of visual acuity, visual field loss, and elderly age.<ref name=":1" /> While characteristic features of visual hallucinations are not specifically linked to the anatomical site of the ocular injury, they usually match to the location of visual loss.<ref name=":1" /> The most commonly accepted theory for Charles Bonnet Syndrome proposes that extreme visual impairment promotes sensory deafferentation, leading to disinhibition, thus resulting in sudden neural firings of the visual cortical regions.<ref name=":1" /> A few studies record that visual hallucinations are likely to be concentrated in the blind regions.<ref name=":2">{{Cite web|last=Reichert|first=David P.|last2=Series|first2=Peggy|last3=Storkey|first3=Amos J.|date=|title=Hallucinations in Charles Bonnet Syndrome Induced by Homeostasis: a Deep Boltzmann Machine Model|url=https://papers.nips.cc/paper/4097-hallucinations-in-charles-bonnet-syndrome-induced-by-homeostasis-a-deep-boltzmann-machine-model.pdf|url-status=live|archive-url=|archive-date=|access-date=|website=NIPS Proceedings|publication-place=University of Edinburgh}}</ref> [[Functional magnetic resonance imaging]] (fMRI) of Charles Bonnet Syndrome patients display a relationship between visual hallucinations and activity in the ventral occipital lobe.<ref name=":1" /> A connection between [[Macular degeneration|age-related macular degeneration]] (AMD) and colored visual hallucinations has been presented.<ref name=":0" /> Color vision signals travel through the parvocellular layers of the [[lateral geniculate nucleus]] (LGN), later transmitting down the color regions of the ventral visual pathway.<ref name=":0" /> Due to cone photoreceptor damage located in the macula, there is a significant reduction of visual input to the visual association cortex, stirring endogenous activation in the color areas and thus leading to colored hallucinations.<ref name=":0" /> Patients with CBS alongside macular degeneration exhibit hyperactivity in the color areas of the visual association cortex (as shown in fMRI’s).<ref name=":0" /> Those with significant ocular disease yet maintain visual acuity may still be susceptible to CBS.<ref name=":0" />
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| The Deep [[Boltzmann machine|Boltzmann Machine]] (DBM) is a way of utilizing an undirected probabilistic process in a neural framework.<ref name=":2" /> Researchers argue that the DBM has the ability to model features of cortical learning, perception, and the visual cortex (the locus of visual hallucinations).<ref name=":2" /> Compelling evidence details the role homeostatic operations in the cortex play in regards to stabilizing neuronal activity.<ref name=":2" /> By using the DBM, researchers show that when sensory input is absent, neuron excitability is influenced, thus potentially triggering complex hallucinations.<ref name=":2" /> | | ==Management== |
| [[File:Acetylcholine Pathway.png|thumb|Acetylcholine Pathway]] | | The mainstay of treatment for visual release hallucinations is reassurance. Patients should be informed that these hallucinations are a common and benign consequence of vision loss. In some cases, [[vision rehabilitation]] and optimizing any remaining vision can help reduce the frequency of hallucinations. If hallucinations are distressing, [[pharmacological treatment]] with medications such as [[antipsychotics]] may be considered, although this is rarely necessary. |
| A short-term change in the levels of feedforward and feedback flows of information may intensely affect the presence of hallucinations.<ref name=":2" /> In periods of drowsiness, CBS related hallucinations are more prone to arise.<ref name=":2" /> Disrupting cortical homeostatic processes after vision has been lost may prevent or setback the emergence of hallucinations.<ref name=":2" /> At varying stages of the cortical grading, [[acetylcholine]] (ACh) may impact the balance of thalamic and intracortical inputs as well as the balance in between bottom-up and top-down.<ref name=":2" /> Particularly in CBS, a shortage of acetylcholine at cortical locations should correspond to the onset of hallucinations.<ref name=":2" />
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| The syndrome can also develop after bilateral optic nerve damage due to methyl alcohol poisoning.<ref>{{cite journal|last1=Olbrich|first1=H. M.|last2=Lodemann|first2=E|last3=Engelmeier|first3=M. P.|year=1987|title=Optical hallucinations in the aged with diseases of the eye|journal=Zeitschrift für Gerontologie|volume=20|issue=4|pages=227–9|pmid=3660920}}</ref>
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| == Diagnosis ==
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| A variety of disciplines including optometry, ophthalmology, geriatric medicine, psychiatry, and neurology play a part in securing the diagnosis of CBS.<ref name=":0" /> Since CBS is not commonly recognized by all clinicians, it oftentimes goes misdiagnosed and identified as psychosis, delirium, or dementia.<ref name=":1" /> As a result of this, it is estimated that almost 60% of CBS patients hesitate to notify their physicians.<ref name=":1" /> By focusing on the specific type of visual hallucination, one may find an accurate diagnosis.<ref name=":1" /> If a patient presents symptoms indicative of Charles Bonnet Syndrome, basic laboratory examinations like metabolic panel and blood count tests, as well as neuroimaging, may aid in an accurate diagnosis.<ref name=":1" />
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| ==Prognosis== | | ==Prognosis== |
| There is no treatment of proven effectiveness for CBS.<ref name=":0" /> For those experiencing CBS, knowing that they are suffering from this syndrome and not a mental illness seems to be the most comforting treatment so far, as it improves their ability to cope with the hallucinations.<ref name=":0" /> As time passes from the initial onset of visual hallucinations, studies show that around 60% of those living with CBS feel that visual hallucinations have no effect on their lives, 33% of people feel that the hallucinations are disruptive to their lives, and 7% of people even find pleasure in the hallucinations.<ref name=":0" />
| | The prognosis for individuals with visual release hallucinations is generally good. The hallucinations may persist but often become less frequent over time. They do not indicate a progression to a more serious condition. |
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| A large proportion of those suffering from CBS develop the visual hallucinations as vision begins to deteriorate and stop hallucinating once vision is entirely gone.<ref name=":2" /> Complex hallucinations may progress over time if the primary loss of vision is due to damage of the early cortical areas.<ref name=":2" /> If activation of the early cortical areas is suppressed when CBS symptoms have already been exhibited, hallucinations may temporarily terminate.<ref name=":2" /> Also, interrupting vision for a short time by closing the eyes or blinking may be helpful.<ref name="Vukicevic/Fitzmaurice" />
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| It is possible for a stressful life event to alter the disposition of hallucinatory experiences as well as the emotional experiences (from unconcerning to concerning) in CBS.<ref name=":3">{{Cite journal|last=Vukicevic|first=Meri|date=2010-08-02|title=Frightening visual hallucinations: atypical presentation of Charles Bonnet syndrome triggered by the Black Saturday bushfires|url=https://www.mja.com.au/journal/2010/193/3/frightening-visual-hallucinations-atypical-presentation-charles-bonnet-syndrome|journal=The Medical Journal of Australia|language=en|volume=193|issue=3|pages=181–182|doi=10.5694/j.1326-5377.2010.tb03843.x}}</ref> As expressed in some patients, an interplay between CBS and an acute or post-traumatic stress disorder may exist.<ref name=":3" /> The role that trauma plays in CBS may affect how and when a hallucinatory episode is triggered.<ref name=":3" />
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| ==History==
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| [[Image:CharlesBonnet.jpg|thumb|200px|[[Charles Bonnet]], the first person to describe the syndrome.]]
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| The disease was first noted by the [[Swiss people|Swiss]] [[natural history|naturalist]] [[Charles Bonnet]], who described the condition in 1760.<ref name=":1" /> He documented it in his 89-year-old grandfather<ref>Bonnet Charles (1760) ''Essai Analytique sur les facultés de l’âme''. Copenhagen: Philibert, pp 426–428</ref> who was nearly blind from [[cataract]]s in both eyes.<ref name="ted" /> After Bonnet’s grandfather received bilateral cataract surgery, his vision evolved from slightly better to complete deterioration over time.<ref name=":0" /> It was around this period that his visual hallucinations started.<ref name=":0" /> His hallucinations consisted of perceptions of men, women, birds, carriages, buildings, tapestries, physically impossible circumstances and scaffolding patterns.<ref name="ted" /><ref>{{cite web |url=http://www.whonamedit.com/synd.cfm/2874.html |title=Bonnet's syndrome (Charles Bonnet) |publisher=Whonamedit |accessdate=2013-07-03 |url-status=live |archiveurl=https://web.archive.org/web/20140223113706/http://www.whonamedit.com/synd.cfm/2874.html |archivedate=2014-02-23 }}</ref> Even though his health was in good shape and he had an absence of any psychiatric disorders, the source of the hallucinations remained unknown.<ref name=":0" /> At forty years old, Charles Bonnet himself suffered from an unrevealed cause of severe vision loss.<ref name=":0" />
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| In 1967, French-Swiss neurologist, [[Georges de Morsier]], coined the term ''Charles Bonnet Syndrome'' in Bonnet's honor.<ref name=":1">{{Cite journal|last=Jan|first=Tiffany|last2=del Castillo|first2=Jorge|date=2012|title=Visual Hallucinations: Charles Bonnet Syndrome|url=https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3555593/|journal=Western Journal of Emergency Medicine|volume=13|issue=6|pages=544–547|doi=10.5811/westjem.2012.7.12891|issn=1936-900X|pmc=3555593|pmid=23357937|via=}}</ref> De Morsier’s description of CBS implies a concentrated neurodegeneration, usually occurring in the elderly with typical cognition.<ref name=":0" /> In 1936, well-renowned neuropsychiatrists, [[Jean Lhermitte]] and [[Julian de Ajuriaguerra]], concluded that visual hallucinations comprise of thalamic lesions as well as ocular pathology.<ref name=":0" /> This definition contradicted De Morsier’s, as he believed there was no ocular pathology involvement in hallucinations.<ref name=":0" /> In psychiatric literature, the most commonly accepted interpretation of CBS is that of Gold and Rabins’.<ref name=":0" /> In 1989, they detailed that the hallucinations associated with CBS are not affecting other sensory modalities.<ref name=":0" /> They believed that the visual hallucinations are oftentimes stereotyped, persistent, and/or repetitive in nature.<ref name=":0" />
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| ==Society and culture== | | ==Epidemiology== |
| | Visual release hallucinations are most commonly seen in older adults with significant vision loss. The prevalence is not well-documented, but it is estimated that a significant proportion of individuals with severe vision impairment experience these hallucinations at some point. |
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| The syndrome is discussed in
| | ==See Also== |
| | * [[Charles Bonnet syndrome]] |
| | * [[Visual hallucinations]] |
| | * [[Vision loss]] |
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| * [[Vilayanur S. Ramachandran]]'s book ''[[Phantoms in the Brain]]''. Ramachandran suggests that [[James Thurber]], who was blinded in one eye as a child, may have derived his extraordinary imagination from the syndrome.<ref>{{cite book|pages=85–7|title=Phantoms in the Brain|author=V.S. Ramachandran| publisher = HarperCollins | year = 1988 |author2=Sandra Blakeslee|author2-link=Sandra Blakeslee|title-link=Phantoms in the Brain|author-link=V.S. Ramachandran}}</ref> | | ==References== |
| * [[Vikram Chandra (novelist)|Vikram Chandra]]'s book ''[[Sacred Games (novel)|Sacred Games]]'' (2006)
| | * Teunisse, R. J., Cruysberg, J. R., Hoefnagels, W. H., Verbeek, A. L., & Zitman, F. G. (1995). Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. ''The Lancet'', 345(8942), 794-797. |
| * [[David Eagleman]]'s book ''[[Incognito: The Secret Lives of the Brain]]''
| | * Menon, G. J. (2005). Complex visual hallucinations in the visually impaired: a structured history-taking approach. ''Archives of Ophthalmology'', 123(3), 349-355. |
| * [[Oliver Sacks]]' 2012 book ''[[Hallucinations (book)|Hallucinations]]''
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| * The Indian movie ''[[Jawan of Vellimala]]'' released in 2012, where [[Mammootty]] is a victim of this disease.<ref name=moviebase>{{cite web|title=Movie Review: Jawan of Vellimala|url=http://www.nowrunning.com/movie/10611/malayalam/jawan-of-vellimala/3951/review.htm|publisher=NowRunning|accessdate=14 January 2013|url-status=live|archiveurl=https://web.archive.org/web/20130101185941/http://www.nowrunning.com/movie/10611/malayalam/jawan-of-vellimala/3951/review.htm|archivedate=1 January 2013}}</ref> | |
| * "The Black Canvas" (2014), a chamber opera by the Greek composer Spyros Syrmos, is about a celebrated painter whose visions are caused by CBS.
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| * [[Margaret Atwood]]'s short story "Torching the Dusties"
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| * [[Deborah Lawrenson]]'s novel "The Lantern" (2011)
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| * Gareth Brookes' graphic novel ''A Thousand Coloured Castles'' (2017)
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| * The 2019 [[Netflix]] film [[Velvet Buzzsaw]]
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| * ''[[Dealt]]'', 2017 documentary about notable victim [[Richard Turner (magician)|Richard Turner]]
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| | [[Category:Ophthalmology]] |
| | [[Category:Neurology]] |
| [[Category:Hallucinations]] | | [[Category:Hallucinations]] |
| [[Category:Abnormal psychology]]
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| [[Category:Symptoms and signs: Cognition, perception, emotional state and behaviour]]
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| [[Category:Psychopathological syndromes]]
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| {{stub}}
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| {{adapted}}
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| Visual Release Hallucinations
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| Synonyms
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N/A
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| Pronounce
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N/A
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| Specialty
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N/A
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| Symptoms
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Visual hallucinations
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| Complications
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N/A
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| Onset
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N/A
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| Duration
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N/A
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| Types
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N/A
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| Causes
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Vision loss, Charles Bonnet syndrome
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| Risks
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N/A
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| Diagnosis
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Clinical evaluation
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| Differential diagnosis
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N/A
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| Prevention
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N/A
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| Treatment
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Reassurance, vision rehabilitation
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| Medication
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N/A
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| Prognosis
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N/A
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| Frequency
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N/A
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| Deaths
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N/A
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Overview
Visual release hallucinations are a phenomenon where individuals experience visual hallucinations due to a lack of visual input, often associated with significant vision loss. These hallucinations are typically non-threatening and are most commonly seen in patients with Charles Bonnet syndrome.
Etiology
Visual release hallucinations occur when there is a significant reduction in visual input to the brain. This can be due to various causes of vision loss, such as macular degeneration, glaucoma, or cataracts. The brain, deprived of normal visual stimuli, may generate its own images, leading to hallucinations.
Pathophysiology
The exact mechanism of visual release hallucinations is not fully understood, but it is believed to involve the visual cortex of the brain. When visual input is reduced or absent, the visual cortex may become hyperactive or "release" stored images, resulting in hallucinations. This is thought to be a compensatory mechanism of the brain to fill in the gaps of missing visual information.
Clinical Presentation
Patients with visual release hallucinations often report seeing complex images such as people, animals, or intricate patterns. These hallucinations are usually vivid and detailed but are recognized by the patient as not being real. Unlike hallucinations associated with psychiatric disorders, these are not accompanied by other sensory or cognitive disturbances.
Diagnosis
Diagnosis of visual release hallucinations is primarily clinical. A thorough medical history and physical examination are essential. It is important to differentiate these hallucinations from those caused by psychiatric conditions or neurological disorders.
Management
The mainstay of treatment for visual release hallucinations is reassurance. Patients should be informed that these hallucinations are a common and benign consequence of vision loss. In some cases, vision rehabilitation and optimizing any remaining vision can help reduce the frequency of hallucinations. If hallucinations are distressing, pharmacological treatment with medications such as antipsychotics may be considered, although this is rarely necessary.
Prognosis
The prognosis for individuals with visual release hallucinations is generally good. The hallucinations may persist but often become less frequent over time. They do not indicate a progression to a more serious condition.
Epidemiology
Visual release hallucinations are most commonly seen in older adults with significant vision loss. The prevalence is not well-documented, but it is estimated that a significant proportion of individuals with severe vision impairment experience these hallucinations at some point.
See Also
References
- Teunisse, R. J., Cruysberg, J. R., Hoefnagels, W. H., Verbeek, A. L., & Zitman, F. G. (1995). Visual hallucinations in psychologically normal people: Charles Bonnet's syndrome. The Lancet, 345(8942), 794-797.
- Menon, G. J. (2005). Complex visual hallucinations in the visually impaired: a structured history-taking approach. Archives of Ophthalmology, 123(3), 349-355.
