High-Order Visual Processing, Visual Symptoms, and Visual Hallucinations: A Possible Symptomatic Progression of Parkinson's Disease

Abstract

Objective: To determine whether Parkinson disease (PD) patients with (VH) have different clinical characteristics and gray-matter volume than those with visual misperceptions (VM) or other visual symptoms (OvS).Background: The spectrum of visual complaints in PD is broad and complex.Methods: We conducted a retrospective chart review of 525 PD patients to identify the frequency of visual symptoms and the association with clinical and radiological features. Brain volumetric MRI data was analyzed using multivariate logistic regression to differentiate cases with and without visual symptoms.Results: Among 525 PD cases, visual complaints were documented in 177 (33.7%). Among these, 83 (46.9%) had VH, 31 (17.5%) had VM, and 63 (35.6%) had OvS (diplopia, blurry vision, photophobia, dry eyes, and eye pain or soreness). When compared to OvS, patients with VH had significantly higher age, duration of disease, rate of REM sleep behavior disorder, and cognitive impairment. Visual hallucinations patients had decreased age-adjusted volumetric averages in 28/30 gray-matter regions when compared to PD without visual symptoms and 30/30 gray-matter regions when compared to VM patients.Conclusions: Visual symptoms in PD may represent a spectrum from OvS to VM to VH, with progression of the latter associated with older age, duration of disease, presence of REM sleep behavior disorder, cognitive impairment, and decreased gray-matter volume.

Seeing ophthalmologic problems in Parkinson disease

“…38 As with many other ophthalmologic symptoms, patients with PD generally do not report diplopia spontaneously, hence treating physicians should actively ask for double vision and other ophthalmologic symptoms. 39,40 In our study, 22% of patients reported visual hallucinations, compared with 30%-60% in previous studies. 41 This discrepancy may be caused by underreporting of visual illusions-having the feeling that someone is in the room or interpreting a shadow as a person-which were part of earlier studies, but not explicitly surveyed by the VIPD-Q.…”

“…Patients with PD experienced more ophthalmologic symptoms across all domains than controls (p < 0.001), as reflected by a higher VIPD-Q total score among patients (median 10 [interquartile range (IQR) 13]) than controls (median 2 [IQR 5]; p < 0.001). Ophthalmologic symptoms interfered with daily activities in 68% (95% CI, 65-71) of patients, compared with 35% (95% CI, [29][30][31][32][33][34][35][36][37][38][39][40][41] of controls (p < 0.001).…”

“…Ophthalmologic symptoms fluctuated during the day in around one-third of patients and may have varied depending on the specific activities at hand; for instance, diplopia may arise only during reading caused by convergence insufficiency, or blurry vision may occur preferentially in a crowded place in patients with impaired visual processing. 39,49,50 The observational nature of our study brings about some limitations. First, the sampling method may have led to a selection bias (patients with visual complaints being more likely to respond), potentially causing an overestimation of ophthalmologic symptoms.…”

Prodromal characteristics of Dementia with Lewy Bodies: baseline results of the Memento nationwide cohort

“…In practice, autonomic disorders should therefore be systematically looked for in a context of mild cognitive disorder, particularly in the case of sicca syndrome, constipation, and rhinorrhea. The description of photophobia in Parkinson's disease was recently done but not in DLB [40]. In our study, the higher the number of core symptoms of DLB present, the higher the frequency of photophobia, with a maximum of 36.3% in the Pro-DLB group.…”

Hallucinations, somatic‐functional disorders of PD‐DLB as expressions of thalamic dysfunction

“…Recent models for visual hallucinations suggest combined impairment in perceptual and attentional networks that leads to altered balance between top‐down and bottom‐up processes . Perception and attention deficit, integrative, and attentional models suggest that production of unrestrained perceptual activity occurs when the attentional focuses are impaired, and the recruited prior perception of a scene is not disconfirmed or blocked by discrepant visual inputs.…”