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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Complex visual hallucinations may affect some normal individuals on going to sleep and are also seen in pathological states, often in association with a sleep disturbance. The content of these hallucinations is striking and relatively stereotyped, often involving animals and human figures in bright colours and dramatic settings. Conditions causing these hallucinations include narcolepsy-cataplexy syndrome, peduncular hallucinosis, treated idiopathic Parkinson's disease, Lewy body dementia without treatment, migraine coma, Charles Bonnet syndrome (visual hallucinations of the blind), schizophrenia, hallucinogen-induced states and epilepsy. We describe cases of hallucinosis due to several of these causes and expand on previous hypotheses to suggest three mechanisms underlying complex visual hallucinations. (i) Epileptic hallucinations are probably due to a direct irritative process acting on cortical centres integrating complex visual information. (ii) Visual pathway lesions cause defective visual input and may result in hallucinations from defective visual processing or an abnormal cortical release phenomenon. (iii) Brainstem lesions appear to affect ascending cholinergic and serotonergic pathways, and may also be implicated in Parkinson's disease. These brainstem abnormalities are often associated with disturbances of sleep. We discuss how these lesions, outside the primary visual system, may cause defective modulation of thalamocortical relationships leading to a release phenomenon. We suggest that perturbation of a distributed matrix may explain the production of similar, complex mental phenomena by relatively blunt insults at disparate sites.
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PMID:Complex visual hallucinations. Clinical and neurobiological insights. 979 40

The Charles Bonnet syndrome (CBS) is a rare disease that also seems to be generally misdiagnosed. Initially described in the XVIII century by the philosopher with the same name, it consist in complex visual hallucinations in elderly people who suffer sensory deprivation with no other psychopathology. The hypothesis on the neurophysiology of hallucinations suggests, as in other diseases that present hallucinations, some implication of thalamus-cortex pathway release. Some authors have proposed CBS as an early marker of dementia and Parkinson's disease. Nevertheless, the results in functional neuroimaging are not conclusive. Regarding treatment, typical and atypical neuroleptics do not seem to be useful and recent studies suggest that the new anticonvulsants could be effcient. The patient should be informed about CBS as a <<non-psychiatric disease>>. In the case reported, the patient presented complex hallucinations with normal SPECT and neuropsychological examinations. The patient did not respond to treatment with risperidone, presenting a favorable evolucion with valpromide. Although further research is needed, this case report supports the efficacy of valpromide in CBS.
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PMID:[The Charles Bonnet syndrome: a case report and a brief review]. 1259 Mar 73

We report two cases of Parkinson's disease in which visual hallucinations disappeared after cataract surgery. Patient 1 was a 72-year-old woman with Parkinson's disease, visual hallucinations and musical hallucinations. Patient 2 was a 77-year-old woman with Parkinson's disease and visual hallucinations. Both patients had severe bilateral cataracts. Though it was difficult to control their visual hallucinations with medication only, cataract surgery made them disappeared quickly. The visual hallucinations of Parkinson's disease are similar to those of Charles Bonnet syndrome. For example, both hallucinations often happen in dim light, at night and when patients are awake with eyes open. Though there have been many reports describing visual hallucinations in Parkinson's disease, there have been few reports discussing the relation between these hallucinations and impaired visual acuity. Similar to the hallucinations of Charles Bonnet syndrome, impaired visual acuity should be related to the visual hallucinations of Parkinson's disease. When Parkinson's disease, visual hallucinations and severe cataract coexist, visual hallucinations may disappear after cataract surgery.
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PMID:[Two cases of Parkinson's disease in which visual hallucinations disappeared after cataract surgery]. 1523 28

The Charles Bonnet syndrome (CBS) commonly designates visual hallucinations (VH) occurring in visually impaired patients. However, there is no consensual definition. The existence of an ophthalmic disease and the absence of cognitive impairment are mandatory or not according to the proposed diagnostic criteria. CBS affects 12 to 15% of visually impaired patients. VH are often repetitive and stereotyped, elementary or complex, involving human figures in most cases. The patients had full insight of the unrealistic character of their VH. The main risk factors are old age and severe visual impairment. Functional imagery studies showed that the VH of SCB correlate with cerebral activity in ventral extrastriate visual cortex and that the hallucinations reflect the functional specializations of this region. This activity could represent release phenomena due to deafferentation of the visual associative cortical areas. No systematic therapeutic trial has been performed. Anticonvulsivant drugs may help in some instances. However, reassurance and explanations are sufficient in most cases. The VH in the hemianopic field after a stroke probably share pathophysiologic mechanisms with CBS. Finally, visual impairment appear as a non specific risk factor for VH in some conditions such as late paraphrenia and some neurodegenerative diseases such as Alzheimer's disease or Parkinson's disease.
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PMID:[Visual hallucinations: the Charles Bonnet syndrome]. 1568 48

We present two cases of Charles Bonnet syndrome in comorbidity with Parkinson's disease. Patients developed visual hallucinosis before starting any antiparkisonian treatment. We briefly discuss the possible physiopathological mechanisms involving low visual acuity and Parkinson's disease with visual hallucinosis.
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PMID:Charles Bonnet syndrome and Parkinson's disease. 1970 68

Charles Bonnet syndrome (CBS) is a condition related to patients with visual loss due to age related macular degeneration or glaucoma that are having complex visual hallucinations. The CBS was first described by Swiss physician Charles Bonnet in 1760. Affected patients, who are otherwise mentally healthy people with significant visual loss, have vivid, complex recurrent visual hallucinations (VHs). One characteristic of these hallucinations is that they usually are "Lilliputian hallucinations" as patients experience micropsia (hallucinations in which the characters or objects are distorted and much smaller than normal). The prevalence of Charles Bonnet Syndrome has been reported to be between 10% and 40%; a recent Australian study has found the prevalence to be 17.5%. The high incidence of non-reported CBS is thought to be as a result of patient's fear to report the symptoms as they could be labeled as mentally insane since those type of visual hallucinations could be found in variety of psychiatric and neurological disorders such as drug or alcohol abuse (delirium tremens), Alice in Wonderland syndrome (AIWS), psychosis, schizophrenia, dementia, narcolepsy, epilepsy, Parkinson disease, brain tumors, migraine, as well as, in long term sleep deprivation. VHs can also be presented as the initial sign of the Epstein-Barr virus infection in infectious mononucleosis. Patients who suffer from CBS usually possess insight into the unreality of their visual experiences, which are commonly pleasant but may sometimes cause distress. The hallucinations consist of well-defined, organized, and clear images over which the subject has little control. It is believed that they represent release phenomena due to deafferentiation of the visual association areas of the cerebral cortex, leading to a form of phantom vision. Cognitive defects, social isolation, and sensory deprivation have also been implicated in the etiology of this condition. This study was conducted on 350 patients diagnosed with Age-Related Macular Degeneration (AMD) and shows incidence of CBS in 13% of patients with AMD. Furthermore, we have found higher incidence of CBS in patients with massive loss of vision in peripheral visual field which is not age related.
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PMID:What associates Charles Bonnet syndrome with age-related macular degeneration? 2130 24

A patient with a history of Parkinson's disease and severe bilateral peripheral vision loss due to vitreous hemorrhages had complex visual hallucinations that persisted for three days and appeared every morning on awakening. The persistent nature of these hallucinations, the patient's preserved insight, and the presence of severe visual impairment was suggestive for Charles Bonnet syndrome rather than Parkinson-related hallucinations. A treatment with carbamazepine was started and proved to be successful. Physicians treating Parkinson patients should be familiar with Charles Bonnet syndrome and consider it as a potential alternative etiology for visual hallucinations, especially when the patient has severely impaired vision and when the hallucinations are sustained during wakefulness.
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PMID:Complex visual hallucinations in a Parkinson patient: don't blame James if it's Charles's fault. 2314 19

Hallucinations of musical notation may occur in a variety of conditions, including Charles Bonnet syndrome, Parkinson's disease, fever, intoxications, hypnagogic and hypnopompic states. Eight cases are described here, and their possible cerebral mechanisms discussed.
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PMID:Hallucinations of musical notation. 2353 17

Charles Bonnet syndrome (CBS) is a condition of visual hallucinations or disturbances occurring in patients with visual pathway pathology not due to underlying psychiatric, metabolic, or neurologic disease. A patient with Parkinson's disease experiencing visual hallucinations was evaluated by the ophthalmology service and found to have decreased vision due to bilateral reversible posterior capsular opacification. The patient's hallucinations did not improve on clozapine, a medication requiring careful monitoring due to potentially severe systemic side effects. However, the hallucinations resolved and vision improved after bilateral treatment of the posterior capsular opacification. Clozapine was then discontinued, and the patient was able to resume his previous Parkinson's disease therapy. This case highlights the importance of considering visual pathway pathology as a contributing factor to visual hallucinations, even in patients with previously diagnosed underlying psychiatric, metabolic, or neurologic disease that could additionally be the etiology of the visual disturbances.
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PMID:Charles Bonnet Syndrome in a Patient with Parkinson's Disease and Bilateral Posterior Capsule Opacification. 3202 92