Project description:BackgroundHydrocephalus is an under-recognized presentation of progressive supranuclear palsy (PSP) and dementia with Lewy bodies (DLB).MethodsWe describe four normal pressure hydrocephalus (NPH)-like presentations of pathology-proven PSP (n = 3) and DLB (n = 1) and review the literature on the hydrocephalic presentation of these atypical parkinsonisms.ResultsDespite the presence of ventriculomegaly disproportionate to the extent of parenchymal atrophy, all patients demonstrated early postural impairment and/or oculomotor abnormalities that encouraged a diagnostic revision. Hallucinations were the only early atypical manifestation of the hydrocephalic DLB presentation.ConclusionsEarly postural impairment, falls, oculomotor impairment, and/or hallucinations are inconsistent with the diagnosis of NPH and suggest PSP or DLB as the underlying NPH mimic. We postulate that previously reported cases of "dual" pathology (e.g., NPH and PSP) actually represent the hydrocephalic presentation of selected neurodegenerative disorders.
Project description:BackgroundDifferential diagnosis between idiopathic normal pressure hydrocephalus (iNPH) associated with parkinsonism (iNPH-P) and Parkinson's disease (PD) may prove difficult when evaluating patients with early parkinsonism. The objective of this study was to evaluate differences in mobility during standardized tasks between iNPH-P and PD.MethodsWe selected 21 iNPH-P and 21 pharmacologically untreated PD patients. They all performed the instrumented Timed Up and Go test at the time of diagnosis.ResultsTurning tasks showed longer duration and lower speed in iNPH-P than in PD. Vertical variation in acceleration during the sit-to-stand phase was lower in iNPH-P patients, whereas the duration of the stand-to-sit phase was longer. On walking, iNPH-P showed smaller stride length and a longer gait cycle duration. In multivariate analysis adjusting for age and cognitive status as potential confounders, average angular speed on turning before sitting was the discriminating parameter between the two groups.ConclusionsPatients with iNPH-P showed specific abnormal mobility performances with respect to untreated PD, specifically during the turning-to-sitting transition.
Project description:PurposeThe clinical presentation of idiopathic normal pressure hydrocephalus (iNPH) may overlap with progressive supranuclear palsy (PSP). The Magnetic Resonance Parkinsonism Index (MRPI), MRPI 2.0, and the interpeduncular angle (IPA) have been investigated to differentiate PSP from healthy controls (HC) and other parkinsonisms. We aimed to assess equivalences and differences in MRPI, MRPI 2.0, and IPA in iNPH, PSP, and HC groups.MethodsWe retrospectively recruited 99 subjects (30 iNPH, 32 PSP, 37 HC) from two institutions. MRI exams, acquired on either 1.5 T or 3 T scanners, included 3D T1-weighted images to measure MRPI, MRPI 2.0, and IPA. Inter- and intra-rater reliability was investigated with the intra-class correlation coefficient (ICC), and the two one-sided t tests (TOST) procedure was used to assess these markers in iNPH, PSP, and HC.ResultsFor all the three measures, intra-rater and inter-rater ICC were excellent (range = 0.91-0.93). In the comparison of iNPH and PSP with HC, differences for MRPI and MRPI 2.0 (p < 0.01 in all cases) and no equivalence (p = 1.00 in all cases) were found at TOST. iNPH and PSP MRPI showed no difference (p = 0.06) and no equivalence (p = 0.08). MRPI 2.0 was not equivalent (p = 0.06) and not different (p = 0.09) in the same two populations. PSP and HC IPA proved equivalent (p < 0.01) while iNPH IPA was different (p < 0.01) and not equivalent (p = 0.96 and 0.82) from both PSP and HC.ConclusionMRPI and MRPI 2.0 significantly overlap in iNPH and PSP, with risk of misdiagnosis, and for this reason may not be helpful in the differential diagnosis.
Project description:Vestibular schwannoma is a common benign tumour that may cause local complications. However, vestibular schwannoma has a known association with communicating hydrocephalus presenting with symptoms of normal pressure hydrocephalus and requiring treatment by ventricular shunting or tumour resection. We report a 79-year-old woman who presented with subacute gait apraxia, cognitive impairment and urinary incontinence. CT and MR imaging identified a 20 mm vestibular schwannoma and communicating hydrocephalus; her cerebrospinal fluid (CSF) protein was elevated. Her symptoms improved following ventriculoperitoneal shunt insertion. The mechanism by which non-obstructing vestibular schwannoma causes hydrocephalus is unclear, but hyperproteinorrachia is probably important, likely by impeding CSF resorption.
Project description:ObjectivesThe aim of this study was to determine the prevalence of idiopathic normal-pressure hydrocephalus (iNPH) in elderly persons in a large population-based sample using radiologic and clinical examinations.MethodsWe examined representative elderly populations aged 70 years and older that had undergone neuropsychiatric evaluations and CT of the brain between 1986 and 2000 (n = 1,238). Gait was evaluated by clinical examination and history of walking difficulty. Cognitive function was evaluated with the Mini-Mental State Examination and urinary incontinence by self-report. iNPH was diagnosed in concordance with the American-European iNPH guidelines. Exclusion criteria were history of meningitis, severe head trauma, and subarachnoid hemorrhage.ResultsThe prevalence of probable iNPH was 0.2% in those aged 70-79 years (n = 2) and 5.9% (n = 24) in those aged 80 years and older, with no difference between men and women. Only 2 of these persons had been treated for iNPH. Hydrocephalic ventricular enlargement, i.e., a CT image consistent with NPH, was found in 56 persons (4.5%). An Evans Index >0.3 was found in 256 (20.7%) and occluded sulci at the high convexity in 67 persons (5.4%). All of these findings were more common in the older age groups.ConclusionsMany elderly possess clinical and imaging features of iNPH, especially those older than 80 years. The number of persons with iNPH is probably much higher than the number of persons currently treated.
Project description:The glymphatic system has in previous studies been shown as fundamental to clearance of waste metabolites from the brain interstitial space, and is proposed to be instrumental in normal ageing and brain pathology such as Alzheimer's disease and brain trauma. Assessment of glymphatic function using magnetic resonance imaging with intrathecal contrast agent as a cerebrospinal fluid tracer has so far been limited to rodents. We aimed to image cerebrospinal fluid flow characteristics and glymphatic function in humans, and applied the methodology in a prospective study of 15 idiopathic normal pressure hydrocephalus patients (mean age 71.3 ± 8.1 years, three female and 12 male) and eight reference subjects (mean age 41.1 + 13.0 years, six female and two male) with suspected cerebrospinal fluid leakage (seven) and intracranial cyst (one). The imaging protocol included T1-weighted magnetic resonance imaging with equal sequence parameters before and at multiple time points through 24 h after intrathecal injection of the contrast agent gadobutrol at the lumbar level. All study subjects were kept in the supine position between examinations during the first day. Gadobutrol enhancement was measured at all imaging time points from regions of interest placed at predefined locations in brain parenchyma, the subarachnoid and intraventricular space, and inside the sagittal sinus. Parameters demonstrating gadobutrol enhancement and clearance in different locations were compared between idiopathic normal pressure hydrocephalus and reference subjects. A characteristic flow pattern in idiopathic normal hydrocephalus was ventricular reflux of gadobutrol from the subarachnoid space followed by transependymal gadobutrol migration. At the brain surfaces, gadobutrol propagated antegradely along large leptomeningeal arteries in all study subjects, and preceded glymphatic enhancement in adjacent brain tissue, indicating a pivotal role of intracranial pulsations for glymphatic function. In idiopathic normal pressure hydrocephalus, we found delayed enhancement (P < 0.05) and decreased clearance of gadobutrol (P < 0.05) at the Sylvian fissure. Parenchymal (glymphatic) enhancement peaked overnight in both study groups, possibly indicating a crucial role of sleep, and was larger in normal pressure hydrocephalus patients (P < 0.05 at inferior frontal gyrus). We interpret decreased gadobutrol clearance from the subarachnoid space, along with persisting enhancement in brain parenchyma, as signs of reduced glymphatic clearance in idiopathic normal hydrocephalus, and hypothesize that reduced glymphatic function is instrumental for dementia in this disease. The study shows promise for glymphatic magnetic resonance imaging as a method to assess human brain metabolic function and renders a potential for contrast enhanced brain extravascular space imaging.
Project description:BackgroundVascular dementia (VaD) and atypical parkinsonism often present with symptoms that can resemble idiopathic normal pressure hydrocephalus (iNPH) and enlarged cerebral ventricles, and can be challenging differential diagnoses. The aim was to investigate frequencies of imaging features usually associated with iNPH and their radiological diagnostic accuracy in a sample containing the relevant differential diagnoses VaD, progressive supranuclear palsy (PSP), multiple system atrophy parkinsonian type (MSA-P), and healthy controls.MethodsNine morphological imaging features usually associated with iNPH were retrospectively investigated in MR images of 55 patients with shunt-responsive iNPH, 32 patients with VaD, 30 patients with PSP, 27 patients with MSA-P, and 39 age-matched healthy controls. Logistic regression and receiver operating characteristic curves were used to assess diagnostic accuracy, sensitivity, and specificity for each imaging finding.ResultsIn a logistic regression model using iNPH diagnosis as a dependent variable, the following imaging features contributed significantly to the model: callosal angle (OR = 0.95 (0.92-0.99), p = 0.012), Evans' index * 100 (OR = 1.51 (1.23-1.86), p < 0.001), enlarged Sylvian fissures (OR = 6.01 (1.42-25.40), p = 0.015), and focally enlarged sulci (OR = 10.18 (1.89-55.02), p = 0.007). Imaging features with 95% specificity for iNPH were: callosal angle ≤ 71°, temporal horns ≥ 7 mm, Evans' index ≥ 0.37, iNPH Radscale ≥ 9, and presence of DESH, bilateral ventricular roof bulgings or focally enlarged sulci. A simplified version of the iNPH Radscale with only four features resulted in equally high diagnostic accuracy as the original iNPH Radscale.ConclusionsThere is a notable overlap between some of the commonly used imaging markers regarding iNPH, VaD and atypical parkinsonism, such as PSP. However, this study shows that the specificity of imaging markers usually associated with iNPH was high even when comparing with these challenging differential diagnoses. The callosal angle was the single imaging feature with highest diagnostic accuracy to discriminate iNPH from its mimics. A simplified rating scale using only a few selected features could be used with retained specificity.