Bonnet Syndrome Research Articles

The Role of Occipital Cortex Hyperexcitability in Visual Snow Syndrome

INTRODUCTION Visual snow syndrome (VSS) is an emerging clinical entity, mainly characterized by persistent, bilateral, whole-visual field, disturbing, small flickering dots or pixelation, floaters, palinopsia, nyctalopia, photopsia, and photophobia. Patients with VSS also describe associated symptoms such as tinnitus, concentration difficulty, lethargy, depression, anxiety, and irritability, all of which affect the patients' quality of life. The consistency of these visual and nonvisual symptoms has recently led to proposed criteria for VSS. The diagnosis relies on the exclusion of other ophthalmic or neuropsychiatric disorders. Interestingly, many patients may have a comorbid migraine, and the symptoms were previously attributed as a persistent visual phenomenon in migraine. VSS is listed in the International Classification of Headache Disorders-Third Edition Appendix as a complication of migraine; however, VSS is a new disease entity distinct from persistent migraine aura. Some patients with VSS recall exposure to illicit hallucinogenic drugs, amphetamines, cannabis, or Lysergic acid diethylamide (LSD). The stereotypic clinical characteristics of VSS are currently well defined, and the pathophysiology is under investigation. Due to the subjective perceptual descriptions of patients with VSS, objective electrophysiologic parameters and functional brain imaging studies using magnetic resonance imaging and positron emission tomography are warranted for defining the quantifiable and reliable outcome measures. Patients with migraine, idiopathic occipital epilepsies, patients with Alice in Wonderland syndrome, patients with Charles Bonnet syndrome, visual hallucinations in recovery from cortical blindness, and recreational 3,4-methylenedioxymethamphetamine/ecstasy users have been suggested to have occipital cortex hyperexcitability. VSS is attributed to involving a dysfunctional magnocellular pathway, thalamocortical dysrhythmia, dysfunctional central visual processing, and occipital cortex hyperexcitability as possible underlying mechanisms. This review will focus on the role of occipital cortex hyperexcitability in VSS and hopefully provide insight into its pathophysiology and therapeutic strategies.

Indirect Traumatic Optic Neuropathy with Associated Charles Bonnet Syndrome

Indirect Traumatic Optic Neuropathy with Associated Charles Bonnet Syndrome

Suppressing visual hallucinations in an adolescent by occipital transcranial magnetic stimulation: A single-case experimental research design

ABSTRACT Visual hallucinations after central or peripheral impairment, commonly called Charles Bonnet syndrome, are often highly distressing and with few available treatment options. Here we report a case where an adolescent developed severely distressing visual hallucinations after hypoxic damage to the occipital cortex following a suicide attempt. The patient received active and sham occipital continuous theta-burst stimulation (cTBS) in a single-case experimental research design and a subsequent open phase, to evaluate cTBS as a Charles Bonnet treatment. The visual hallucinations seemed to decrease more during active than sham cTBS in the blind phase, and in the following week of repeated five daily treatments they almost disappeared. A normalization of increased activity in the lateral visual network after cTBS was observed on a functional magnetic resonance imaging resting-state analysis compared with 42 healthy controls. Visual evoked potentials stayed largely unchanged both in the sham-controlled blind phase and the subsequent open phase. During the two weeks after the open phase with repeated cTBS sessions, the visual hallucinations gradually reappeared and almost returned to the baseline level. Our findings suggest that active cTBS over the primary visual cortex can reduce visual hallucinations through modulation of downstream visual regions, though the effect is temporally limited.

Abstract 1122‐000107: Charles Bonnet Syndrome Secondary to Massive Dural Arteriovenous Fistula Disguised as Extensive Venous Sinus Thrombosis

This meeting abstract was removed due to the OA licensing requirements of this journal. The full abstract is listed here : https://www.svin.org/files/SVIN_2021_Abstracts_for_Web.pdf

Charles Bonnet Syndrome in Patients with Open-Angle Glaucoma: Prevalence and Correlation to Visual Field Loss

To determine the prevalence and characteristics of Charles Bonnet Syndrome (CBS) and its relation to visual field loss (VFL) in patients with open-angle glaucoma (OAG). Prospective, cross-sectional study. Adult patients (n= 337) with manifest OAG with verified VFL and without significant macular disease or extraocular conditions known to cause visual hallucinations. Patients attending the glaucoma outpatient department of the Skåne University hospital, Malmö, Sweden, between April 1, 2018, and December 31, 2018, were consecutively evaluated for inclusion. Potentially eligible patients admitting to having complex visual hallucinations were interviewed to explore the characteristics of their hallucinatory experiences. Recent automated visual field examinations were available for all participants, and swept-source OCT was performed in participants with CBS to rule out previously undiagnosed macular pathology. The correlation between potential risk factors and CBS was evaluated with logistic regression analysis. Prevalence of CBS in patients with OAG. Charles Bonnet Syndrome was found in 7.1% (95% confidence interval [CI], 4.7-10.6) of patients with OAG. Participants with CBS were more likely to have at least 1 eye with a visual field index (VFI) of ≤30% compared with those without CBS (71% vs. 34.2%; P= 0.001). Although the best-corrected visual acuity (BCVA) in the worse eye was significantly lower in participants with CBS (decimal equivalent of Snellen BCVA: 0.25 vs. 0.6, P= 0.003), 33% of these participants had a BCVA of ≥0.5 in the worse eye. In multivariable analysis, CBS was correlated to the VFI of the better eye (odds ratio, 0.984; 95% CI, 0.969-0.998, P= 0.030) and the BCVA of the worse-seeing eye (odds ratio, 0.210; 95% CI, 0.046-0.952, P= 0.043). Charles Bonnet Syndrome was not a rare condition in patients with glaucoma. Patients with a combination of advanced VFL and low BCVA had the highest risk of CBS; however, 1 of 3 patients with CBS hada BCVA of ≥0.5 in both eyes. These findings emphasize the importance of being attentive to symptoms ofCBS in patients with glaucomatous VFL even when visual acuity is preserved.

Auditory Hallucinations in Charles Bonnet Syndrome: A Case Report

Auditory Hallucinations in Charles Bonnet Syndrome: A Case Report

Visual Phenomena Associated With Migraine and Their Differential Diagnosis.

Visual phenomena are of many different kinds; their differential diagnosis is usually possible with directed history-taking. In this review, we describe common visual phenomena that must be distinguished from a migraine aura. This review is based on publications retrieved by a selective search in PubMed and the Web of Knowledge/Science, with special attention to the current classification of the International Headache Society and the recommendations of the German Migraine and Headache Society. The following search terms were used: "visual phenomena/phenomenon," "migraine aura," and "persistent/complication/ long-lasting/ongoing." The most helpful questions for differential diagnosis are whether the symptoms are present in one eye only or in both, whether their onset was sudden or over minutes or days, and whether the phenomenon has occurred only once or repeatedly, or is persistently present. A visual aura associated with migraine must be distinguished, in rare cases, from an isolated epileptic aura, from cerebral/retinal ischemia, or from visual snow. Further differential diagnoses include a persisting perceptual disturbance after hallucinogen use (HPPD, "hallucinogen persisting perception disorder") and the Charles Bonnet syndrome (CBS); the latter arises as a consequence of severely impaired vision. Posterior reversible encephalopathy syndrome (PRES) is rare and generally reveals itself over its further course through the appearance of additional clinical manifestations. Primary ophthalmological causes can usually be readily identified and classified by ophthalmological examination. Patients with visual phenomena typically consult physicians from various medical specialties. A correct differential diagnosis can be made based on the history if the physician views the symptoms in their overall context to determine the particular disease entity that is responsible.

A Case of Heidenhain Variant of Creutzfeldt-Jakob Disease Mimicking A Charles Bonnet Syndrome

Hallucinations are common in different clinical disorders associated with older age. The differential diagnosis of new onset complex visual hallucinations is vast. A case is reported of a 70-year-old man who presented with visual impairment attributed to retinopathy, that then developed complex visual hallucinations. Charles Bonnet syndrome (CBS) was initially diagnosed. Throughout the course if his disease, he developed rapidly progressive dementia associated with myoclonus and pyramidal signs.

Associations between Age-Related Eye Diseases and Charles Bonnet Syndrome in Participants of the Age-Related Eye Disease Study 2: Report Number 26

Eyecare professionals should be aware of Charles Bonnet Syndrome (CBS), a phenomenon involving visual hallucinations in people with visual impairments. We examined prevalence of CBS among AREDS2 participants and its associations with age-related eye diseases.

Charles Bonnet syndrome in patients with Stargardt disease: prevalence and risk factors

AimsTo describe the prevalence of the Charles Bonnet syndrome (CBS) and search for potential CBS risk factors in a Dutch Stargardt disease (STGD1) cohort.MethodsEighty-three patients with STGD1 were screened for...

Causes of visual hallucinations in Parkinson's disease

HintergrundVisuelle Halluzinationen (VH) werden zumeist als Spätsymptome der Parkinson-Krankheit (PK) angesehen. Sie kommen jedoch in leichterer Form auch in Frühstadien der Erkrankung vor. Ursächlich wurden VH anfänglich als Folge einer dopaminergen Überstimulation gesehen, später ebenso im Rahmen einer demenziellen Entwicklung der PK.FragestellungDie vorliegende Arbeit untersucht, ob sich das Entstehungsmodell der VH in den letzten Jahren erweitert hat.Material und MethodikBasierend auf klinischen, pharmakologischen und neuropathologischen Arbeiten sowie funktioneller Magnetresonanzgraphie erfolgt eine systematische Aufgliederung in monomodale und multimodale Entstehungsmodelle der VH. Die Anwendbarkeit auf unterschiedliche VH-Formen und -Auslösungsmomente wird jeweils kritisch beleuchtet.ErgebnisseEinbußen bei der visuellen Informationsaufnahme und -verarbeitung, Defizite der Aufmerksamkeit und fehlerhafte Konnektivität zwischen kortikalen Netzwerken werden herausgearbeitet. Es bestehen z. T. Überlappungen mit dem Lhermitte-Syndrom und dem Charles-Bonnet-Syndrom. Kein Modell erklärt jedoch befriedigend alle Spielarten der VH. Nicht alle VH weisen die gleiche Pathogenese und stets eine schlechte Prognose auf.SchlussfolgerungDie Ursachenkette visueller Halluzinationen ist komplex und individuell unterschiedlich. Inwieweit dies therapeutisch einsetzbar ist, ist bisher wenig erforscht. Es gibt erste Hinweise, dass neben einer Änderung der Medikation auch Visusverbesserung, die Einbindung des Partners/der Partnerin und vielleicht individuell anpassbare Copingstrategien erfolgreich eingesetzt werden könnten.

Charles Bonnet syndrome in a young adult with diabetic retinopathy.

Charles Bonnet syndrome in a young adult with diabetic retinopathy.

Atypical Charles Bonnet syndrome secondary to frontal meningioma: a case report

BackgroundCharles Bonnet Syndrome (CBS) is a rare clinical entity that is classically composed of visual hallucinations in the context of an altered optic pathway with preservation of reality judgment. This case aims to present the association of visual hallucinations with complex alterations of the nervous structures adjacent to the visual pathway and an atypical clinical presentation, thus explaining the possible mechanisms involved in the generation of these symptoms.Case presentationA 43-year-old man presents seeking care due to visual hallucinations with partial preservation of reality judgment and symptoms compatible with a major depressive disorder, including irritability and diminished hygiene habits. He has a history of complete gradual loss of vision and hyposmia. Due to poor treatment response during hospitalization, an MRI was obtained, which showed a frontal tumor lesion with meningioma characteristics adjacent to the olfactory groove and compression of the optic chiasm. He underwent surgical resection of the lesion, which remitted the psychotic symptoms, but preserving the visual limitation and depressive symptoms.ConclusionsThe presence of visual hallucinations, without other psychotic features as delusions, is a focus of attention for basic structural pathologies in the central nervous system. Affection at any level of the visual pathway can cause CBS. When finding atypical symptoms, a more in-depth evaluation should be made to allow optimization of the diagnosis and treatment.

Acute Onset of Charles Bonnet Syndrome After Unilateral Central Retinal Artery Occlusion in the Background of Tense Orbit.

Acute Onset of Charles Bonnet Syndrome After Unilateral Central Retinal Artery Occlusion in the Background of Tense Orbit.

An 81-year-old woman with nocturnal hallucinations due to Charles Bonnet syndrome

The presence of nocturnal hallucinations can be indicative of several underlying causes, one of which is represented by Charles Bonnet syndrome (CBS), a pathology characterized by the occurrence of nighttime hallucinations in the absence of visual stimuli. This condition predominantly affects elderly patients, with an average age range between 75 and 85 years old. However, this pathology is often underdiagnosed due to the lack of interdisciplinary cooperation and knowledge regarding this syndrome. The present article aims to highlight a case study of a patient who has been experiencing distressing nocturnal hallucinations for approximately 2 years. The patient was eventually diagnosed with visual impairments as the underlying cause of the hallucinations.

Lockdown and visual hallucinations in older people: a community perspective

ObjectiveAfter COVID-19 was declared as a pandemic, different countries have enforced lockdowns, and shielding to mitigate the spread of the virus as preventing loss of lives was the priority.Our aim is to look for possible explanations for increased rates of visual hallucinations presented to Community Mental Health Teams for Older People during the period of lockdown.Case reportA review of clinical cases presenting with new onset visual hallucinations to the Community Mental Health Teams for Older People during the lockdown period in 2020 was summarised in two case scenarios. One scenario represents cases with known background of dementia, while the other scenario represents new referrals during the lockdown period with no known psychiatric background. In those cases, the visual hallucinations started during lockdown with no clear cause, did not respond to psychotropic medications, physical health investigations were all normal and hallucinations improved markedly with the end of the lockdown and social isolation.DiscussionFrom clinical practice point of view, during the period of lockdown in the COVID-19 pandemic, visual hallucinations has been one of the commonest presentations reported to the Community Mental Health Teams for Older People. Families were calling frequently reporting that their loved ones were “seeing things”. Possible underlying causes include: social isolation, sensory and perceptual deprivation, visual impairment and Charles Bonnet syndrome, lack of cognitive stimulation activities with progress of dementia, superimposed delirium, in addition to depression secondary to loneliness, reduction in community support, increased alcohol consumption and negative effects of repeated media consumption.ConclusionThere has been a marked increase in reporting visual hallucinations in the shielding older people population in the community during the period of lockdown in the COVID-19 pandemic. This shielded population was not exposed to COVID-19, so it didn't give an explanation to this new phenomenon. Though there are multiple possible causative factors, the effect of the lockdown itself with its resultant social isolation and sensory deprivation remains to be the most significant. Shielding the older people population throughout the COVID-19 pandemic came as an essential measure as the physical safety and preventing loss of lives was the priority; however the lockdown had significant negative effects on the mental health of the shielding population. It remains unclear if those negative effects are going to be reversible in the future, resulting in poor quality of life.

This issue of ACTA

This issue of ACTA

¡ I see presenters in my house !

IntroductionCharles Bonnet syndrome (CBS) is characterized by the presence of visual hallucinations, generally complex, which occurs in patients with alterations in the visual pathway. The majority of affected patients are elderly. It appears in 15% of people with visual loss, predominantly in the 80-year-old female gender.ObjectivesTo present a clinical case of a patient with visual hallucinations and a possible diagnosis of Charles Bonnet syndrome. Highlight the importance of an adequate differential diagnosis.MethodsBibliographic review of the treatment and diagnosis of CBS, from articles published in the last 5 years in Pubmed.ResultsWoman, 80 years old. No ophthalmological history except those associated with advanced age. She goes to the emergency room due to the presence of visual hallucinosis, in the form of “television presenters” of whom she makes partial criticism, being aware most of the time of their unreality. Hallucinations are not accompanied by anxiety or significant affective repercussions. Discarded delirium, intoxication by substances or drugs that cause the condition. Currently under follow-up to rule out other causes.ConclusionsThe diagnosis of SCB requires a multidisciplinary approach between neurologists, psychiatrists and ophthalmologists in order to avoid erroneous diagnoses. The differential diagnosis should be made with pathologies such as Lewy body dementia, Parkinson’s disease, delirium, substance intoxication, migraine aura, and metabolic encephalopathy, among others. It is important to involve the family in the treatment of the syndrome to reinforce the recognition of the unreality of these hallucinations in the patients. Antipsychotic treatment can be effective only if the condition is extremely distressing.

Charles bonnet sydrome: A case report

IntroductionFaced with recent onset psychotic symptoms in patients over 60 years of age without a psychiatric history, it is important to carry out an adequate differential diagnosis.ObjectivesThe objective is to carry out a review of Charles Bonnet syndrome through the presentation of a caseMethods75-year-old patient who suddenly began to present auditory hallucinations. The patient had no relevant psychiatric history or medical history. She reported that suddenly, two months ago, she had begun to listen to his neighbor through the walls of his home. She heard him talk about her, threatening and insulting her. Later, as a result of these hallucinations, she began to believe that in the bathroom he was spying on her through a camera, forcing her to shower in the dark. Weeks later, she thought that he was also chasing her down the street through a chip that had implanted her. She was distressed and highly anxious. She had started not sleeping out of fear of this neighbor.ResultsIn addition to the psychiatric evaluation, an MRI was requested to rule out incipient cognitive deterioration, as well as a hearing examination. It was found that he had severe hearing loss in the left ear. Given these findings, he was diagnosed with Charles Bonnet syndrome.ConclusionsCharles Bonnet syndrome is normally associated with blindness, however, it is also described in deafness. It occurs with hallucinations of the lost sensory organ. It is a clinical picture that does not respond well to treatments.DisclosureNo significant relationships.

ERPS AS AN INDEX OF IMPAIRED WORKING MEMORY IN AN ISCHEMIC BRAIN STROKE APHASIC PATIENT AWAKENED FROM A LONG-TERM COMA FOLLOWING AN AMPHETAMINE OVERDOSE

Nowadays, amphetamines constitute the prescription drugs most commonly abused by adolescents and young adults (Berman, O’Neill, Fears et al. 2008). The prevalence of problematic (mainly illegal) use of amphetamines as a stimulant by college students, and here especially before serious examinations, has also been rising. This fact represents a serious public health concern. The patient, aged 19, was awakened from from a long-term coma that had lasted 21 days following an amphetamine overdose and manifested tetraparesis, cortical blindness and deficits in cognitive and emotional processes. After a year of rehabilitation the majority of symptoms had disappeared, but cortical blindness andworking memory deficits remained. In addition, frontal lobe syndrome symptoms appeared. After two years of therapy as a result of immense tiredness caused by all an night wedding reception she started to manifest Charles-Bonnet syndrome. She experienced strange visual sensations such as visual hallucinations and saw various non-existing shapes (coloured blots, patterns and fireworks of vivid colours). She also saw objects (often terrifying) as well as animals (mainly African) and people with deformed faces and long teeth, and persons in African dress with feathers and coral beads in their hair. Her real identity was not remembered by the patient for longer than 2 hours and even then she insisted on being referred to as Shakira. She was given a qEEG examination (in open and closed eyes conditions) and ERPs with the use of auditory stimuli at the period when the hallucinations (to a small degree) still occurred. Studies conducted into the functional neuroimaging of the brain work in milliseconds in the examined patient can explain her symptoms. A comparison of the subject’s ERPs with the grand average of ERPs in healthy controls shows that the N170 and N 250 components are impaired in the subject: the occipital-temporal area of the subject brain shows a strong positivity instead of negativities. This positivity might reflect an enhanced reactivity of neurons in the corresponding area induced by the removal of lateral inhibition from the neurons as a result of local damage. ------------------------------------------------------------------------------------------------------------------------------------