Visual hallucinations in the differential diagnosis of parkinsonism: Table 1

Abstract

Visual hallucinations (VH) occur commonly in Parkinson's disease (PD) and dementia with Lewy bodies (DLB) but are reported much less frequently in other neurodegenerative causes of parkinsonism, such as progressive supranuclear palsy, multiple system atrophy and corticobasal degeneration syndrome. This clinical sign may be helpful when considering the differential diagnosis of patients with parkinsonism. The observation that VH may be specific to Lewy body pathology probably reflects a greater vulnerability of the visual systems to PD and DLB neurodegeneration compared with other diseases. Topographic differences in pathology are probably the major factor producing VH in Lewy body diseases, rather than neurophysiological changes that are specific to α-synuclein protein accumulation. VH correlate with pathology in the limbic system and more specifically the amygdale that is frequently affected in PD and DLB but relatively preserved in other forms of parkinsonism often misdiagnosed as PD. In this review, the published frequencies of VH in these different conditions are compared to put into context the notion of VH as a clinical clue to underlying Lewy body pathology.

Kognitif Affektif Serebellar Sendrom ve Psikoz Bulguları ile Ortaya Çıkan bir Multisistem Atrofi (MSA-C) Olgusu

“…These types of vivid and realistic hallucinations were previously reported in MSA patients (14) and they bear clinical resemblance to pedunculer hallucinosis. Peduncular hallucinosis may occur as a result of damage to the brainstem reticular formation or thalamus' input pathways, or the inhibitory serotoninergic neurons associated with raphe nucleus (15). Cerebellar vermis' connection to reticular formation, raphe nucleus and thalamus (16,17) satisfy the necessary anatomical basis for this condition and strengthen the possibility that the hallucinations seen in our case were peduncular hallucinations when the clinical findings are taken into account.…”

Distinguishing Neuroimaging Features in Patients Presenting with Visual Hallucinations

“…34 In contrast, synucleinopathies without Lewy bodies, such as multisystem atrophy, have a low incidence of visual hallucinations. 35 Lewy Body Dementia. Lewy body dementia is the second most common form of dementia after Alzheimer disease.…”

“…Visual hallucinations form part of the core clinical diagnostic criteria for Lewy body dementia and are typically seen early in the course of the disease, before the development of Parkinsonian motor symptoms. 36 The incidence of VHs in Lewy body dementia varies between 20% and 75%, 31,33,35 and the presence of VH provides an 83% positive predictive value for distinguishing Lewy body dementia from Alzheimer disease. 37 VHs in Lewy body dementia typically manifest as prolonged well-formed complex scenes of figures and objects and provoke varied reactions from fear through to indifference.…”

Treatment of camptocormia with botulinum toxin

“…Various brainstem structures are known to be involved in regulation of sleep (Boeve et al, 2007), and disruption to serotonergic and cholinergic outputs from the brainstem to the thalamus may play a role in the development of visual hallucinations (Bertram and Williams, 2012). Sleep studies in PD camptocormia show an increased rate of periodic leg movements of sleep (Lavault et al, 2009) and one study suggested reduced midbrain and pontine size may explain this correlation (Bonneville et al, 2008).…”