Parkinsonian syndromes associated with hydrocephalus: case reports, a review of the literature, and pathophysiological hypotheses

Is there a spinal tap responder in progressive supranuclear palsy? The first prospective study

OBJECTIVE

Progressive supranuclear palsy (PSP) is a progressive neurodegenerative disease, and sometimes shows idiopathic normal pressure hydrocephalus (iNPH)-like presentations. We aimed to evaluate spinal tap responsiveness in patients with PSP, including the effect of sham spinal tap.

METHODS

Eleven patients with PSP, ten with probable/definite iNPH, and eight control patients were prospectively enrolled. All participants underwent sham spinal tap and spinal tap procedures. Gait was evaluated using wearable inertial sensors. We defined "tap responders" as individuals with a 10% or more improvement from baseline in any of the gait parameters (timed up-and-go test total time, stride length, and velocity during straight walking under single-task and cognitive dual-task conditions). We compared the ratio of responders in patients with PSP to patients with iNPH and controls.

RESULTS

The ratio of tap responders and the ratio of sham tap responders in patients with PSP were significantly higher than those in control patients, and not different from those in patients with iNPH. PSP patients with iNPH-like MRI features tended to respond to the spinal tap compared to those without such imaging features. Notably, one patient with PSP, who responded to the spinal tap beyond the effect of sham spinal tap, was treated by the shunt operation.

CONCLUSION

This is the first prospective study to demonstrate tap and shunt responsiveness in patients with PSP while highlighting the placebo effects of the spinal tap in patients with PSP or iNPH. Our findings suggest that some PSP patients have impaired cerebrospinal fluid circulation, contributing to a distinct component of the clinical spectrum.

Structural neuroimaging markers of normal pressure hydrocephalus versus Alzheimer's dementia and Parkinson's disease, and hydrocephalus versus atrophy in chronic TBI-a narrative review

Introduction

Normal Pressure Hydrocephalus (NPH) is a prominent type of reversible dementia that may be treated with shunt surgery, and it is crucial to differentiate it from irreversible degeneration caused by its symptomatic mimics like Alzheimer's Dementia (AD) and Parkinson's Disease (PD). Similarly, it is important to distinguish between (normal pressure) hydrocephalus and irreversible atrophy/degeneration which are among the chronic effects of Traumatic Brain Injury (cTBI), as the former may be reversed through shunt placement. The purpose of this review is to elucidate the structural imaging markers which may be foundational to the development of accurate, noninvasive, and accessible solutions to this problem.

Methods

By searching the PubMed database for keywords related to NPH, AD, PD, and cTBI, we reviewed studies that examined the (1) distinct neuroanatomical markers of degeneration in NPH versus AD and PD, and atrophy versus hydrocephalus in cTBI and (2) computational methods for their (semi-) automatic assessment on Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) scans.

Results

Structural markers of NPH and those that can distinguish it from AD have been well studied, but only a few studies have explored its structural distinction between PD. The structural implications of cTBI over time have been studied. But neuroanatomical markers that can predict shunt response in patients with either symptomatic idiopathic NPH or post-traumatic hydrocephalus have not been reliably established. MRI-based markers dominate this field of investigation as compared to CT, which is also reflected in the disproportionate number of MRI-based computational methods for their automatic assessment.

Conclusion

Along with an up-to-date literature review on the structural neurodegeneration due to NPH versus AD/PD, and hydrocephalus versus atrophy in cTBI, this article sheds light on the potential of structural imaging markers as (differential) diagnostic aids for the timely recognition of patients with reversible (normal pressure) hydrocephalus, and opportunities to develop computational tools for their objective assessment.

Case report: Levodopa-responsive parkinsonism with akinetic mutism after ventriculo-peritoneal shunt

Background

Parkinsonism and akinetic mutism (AM) following ventriculo-peritoneal shunt (VPS) without underdrainage used to be considered rare, but may be underdiagnosed in daily clinical practice. Although the pathophysiology is still unclear, in several case reports, the parkinsonism and AM after VPS shows responsiveness to dopaminergic treatment.

Case presentation

We report a 19-year-old male that presented with severe parkinsonism and AM after VPS. Meanwhile, ¹⁸F-FDG-PET showed a cortical and subcortical hypometabolism. Fortunately, levodopa dramatically improved patient's symptoms and brain hypometabolism. This report provides support for the possibility that dopamine deficiency inhibits brain metabolism, and further elucidates the pathogenesis of parkinsonism and AM.

Conclusion

This report highlights the presentation of a treatable parkinsonism and points out that Levodopa and/or dopamine agonist should be the first choice if the patients develop parkinson-like symptoms after VPS.

Parkinsonism after ventriculoperitoneal shunt for hydrocephalus

BACKGROUND

Parkinsonism after ventriculoperitoneal shunt in patients with hydrocephalus is a rare and profound complication that is often misdiagnosed, causing treatment to be delayed. To date, the characteristics of this disease have not been well described and summarized. Here, we report a rare case of parkinsonism after ventriculoperitoneal shunt; symptoms were aggravated by antipsychotic drugs but showed a good response to Madopar. Such cases have rarely been reported previously.

CASE PRESENTATION

A 44-year-old man presented with parkinsonism, bilateral pyramidal tract signs, and oculomotor impairment four years after a successful ventriculoperitoneal shunt for idiopathic aqueduct stenosis resulting in obstructive hydrocephalus. Brain magnetic resonance imaging and computed tomography showed fluctuations in the lateral ventricle and the third ventricle without any intervention. The patient's condition was aggravated by antipsychotic drugs but showed a good response to Madopar.

CONCLUSION

This observation suggests that parkinsonism in this patient was caused by reversible dysfunction of the presynaptic nigrostriatal dopaminergic pathway due to fluctuations in the lateral ventricle, representing the first hit to the dopaminergic signalling pathway, and antipsychotic drugs had an antagonistic effect on dopamine D2 receptors, representing the second hit. In addition, we summarize the pathophysiological mechanisms, clinical manifestations, treatments, and prognoses of this complication in 38 patients who met the inclusion criteria in 24 previous studies to increase neurologists' understanding of the disease.

White matter hyperintensities burden in the frontal regions is positively correlated to the freezing of gait in Parkinson's disease

Objective

Previous studies have reported that white matter hyperintensities (WMHs) are associated with freezing of gait (FOG), but it is not clear whether their distribution areas have correlations with FOG in Parkinson's disease (PD) and the potential influencing factors about WMHs.

Methods

Two hundred and forty-six patients with PD who underwent brain MRI were included. Participants were divided into PD with FOG (n = 111) and PD without FOG (n = 135) groups. Scheltens score was used to assess the WMHs burden in the areas of deep white matter hyperintensities (DWMHs), periventricular hyperintensities (PVHs), basal ganglia hyperintensities (BGHs), and infratentorial foci of hyperintensities (ITF). Whole brain WMHs volume was evaluated by automatic segmentation. Binary logistic regression was used to evaluate relationships between WMHs and FOG. The common cerebrovascular risk factors that may affect WMHs were evaluated by mediation analysis.

Results

There were no statistical differences between PD with and without FOG groups in whole brain WMHs volume, total Scheltens score, BGHs, and ITF. Binary logistic regression showed that the total scores of DWMHs (OR = 1.094; 95% CI, 1.001, 1.195; p = 0.047), sum scores of PVHs and DWMHs (OR = 1.080; 95% CI, 1.003, 1.164; p = 0.042), especially the DWMHs in frontal (OR = 1.263; 95% CI, 1.060, 1.505 p = 0.009), and PVHs in frontal caps (OR = 2.699; 95% CI, 1.337, 5.450; p = 0.006) were associated with FOG. Age, hypertension, and serum alkaline phosphatase (ALP) are positively correlated with scores of DWMHs in frontal and PVHs in frontal caps.

Conclusion

These results indicate that WMHs distribution areas especially in the frontal of DWMHs and PVHs play a role in PD patients with FOG.

Movement Disorders Associated With Radiotherapy and Surgical Procedures

Occasionally, movement disorders can occur following interventional procedures including but not limited to radiotherapy, dental procedures, and cardiac, cerebral and spinal surgeries. The majority of these disorders tend to be unexpected sequelae with variable phenomenology and latency, and they can often be far more disabling than the primary disease for which the procedure was performed. Owing to poor knowledge and awareness of the problem, delays in diagnosing the condition are common, as are misdiagnoses as functional movement disorders. This narrative review discusses the phenomenology, pathophysiology, and potential treatments of various movement disorders caused by interventional procedures such as radiotherapy and neurological and non-neurological surgeries and procedures.

Modulation of striatal glutamatergic, dopaminergic and cholinergic neurotransmission pathways concomitant with motor disturbance in rats with kaolin-induced hydrocephalus

BACKGROUND

Hydrocephalus is characterized by abnormal accumulation of cerebrospinal fluid in the cerebral ventricles and causes motor impairments. The mechanisms underlying the motor changes remain elusive. Enlargement of ventricles compresses the striatum of the basal ganglia, a group of nuclei involved in the subcortical motor circuit. Here, we used a kaolin-injection juvenile rat model to explore the effects of acute and chronic hydrocephalus, 1 and 5 weeks post-treatment, respectively on the three major neurotransmission pathways (glutamatergic, dopaminergic and cholinergic) in the striatum.

METHODS

Rats were evaluated for motor impairments. Expressions of presynaptic and postsynaptic protein markers related to the glutamatergic, dopaminergic, and cholinergic connections in the striatum were evaluated. Combined intracellular dye injection and substance P immunohistochemistry were used to distinguish between direct and indirect pathway striatal medium spiny neurons (d and i-MSNs) for the analysis of their dendritic spine density changes.

RESULTS

Hydrocephalic rats showed compromised open-field gait behavior. However, male but not female rats displayed stereotypic movements and compromised rotarod performance. Morphologically, the increase in lateral ventricle sizes was greater in the chronic than acute hydrocephalus conditions. Biochemically, hydrocephalic rats had significantly decreased striatal levels of synaptophysin, vesicular glutamate transporter 1, and glutamatergic postsynaptic density protein 95, suggesting a reduction of corticostriatal excitation. The expression of GluR2/3 was also reduced suggesting glutamate receptor compositional changes. The densities of dendritic spines, morphological correlates of excitatory synaptic foci, on both d and i-MSNs were also reduced. Hydrocephalus altered type 1 (DR1) and 2 (DR2) dopamine receptor expressions without affecting tyrosine hydroxylase level. DR1 was decreased in acute and chronic hydrocephalus, while DR2 only started to decrease later during chronic hydrocephalus. Since dopamine excites d-MSNs through DR1 and inhibits i-MSNs via DR2, our findings suggest that hydrocephalus downregulated the direct basal ganglia neural pathway persistently and disinhibited the indirect pathway late during chronic hydrocephalus. Hydrocephalus also persistently reduced the striatal choline acetyltransferase level, suggesting a reduction of cholinergic modulation.

CONCLUSIONS

Hydrocephalus altered striatal glutamatergic, dopaminergic, and cholinergic neurotransmission pathways and tipped the balance between the direct and indirect basal ganglia circuits, which could have contributed to the motor impairments in hydrocephalus.

Parkinsonism in idiopathic normal pressure hydrocephalus: is it time for defining a clinical tetrad?

Background

Association between parkinsonism and idiopathic normal pressure hydrocephalus (iNPH) still remains debated. There is already plenty of evidences in the literature suggesting that this clinical sign can be considered as an integral part of the clinical spectrum of iNPH patients.

Methods

We reviewed the possible pitfalls in the core clinical definition of iNPH based on available international diagnostic criteria, phenomenology of parkinsonism in iNPH, and neuroimaging supporting the presence of parkinsonism in iNPH.

Conclusions

We argue that the diagnostic definition of the iNPH “triad” should be possibly reconsidered as a “tetrad” also including parkinsonism.

Clinical Aspects of the Differential Diagnosis of Parkinson's Disease and Parkinsonism

Parkinsonism is a clinical syndrome presenting with bradykinesia, tremor, rigidity, and postural instability. Nonmotor symptoms have recently been included in the parkinsonian syndrome, which was traditionally associated with motor symptoms only. Various pathologically distinct and unrelated diseases have the same clinical manifestations as parkinsonism or parkinsonian syndrome. The etiologies of parkinsonism are classified as neurodegenerative diseases related to the accumulation of toxic protein molecules or diseases that are not neurodegenerative. The former class includes Parkinson's disease (PD), multiple-system atrophy, progressive supranuclear palsy, and corticobasal degeneration. Over the past decade, clinical diagnostic criteria have been validated and updated to improve the accuracy of diagnosing these diseases. The latter class of disorders unrelated to neurodegenerative diseases are classified as secondary parkinsonism, and include drug-induced parkinsonism (DIP), vascular parkinsonism, and idiopathic normal-pressure hydrocephalus (iNPH). DIP and iNPH are regarded as reversible and treatable forms of parkinsonism. However, studies have suggested that the absence of protein accumulation in the nervous system as well as managing the underlying causes do not guarantee recovery. Here we review the differential diagnosis of PD and parkinsonism, mainly focusing on the clinical aspects. In addition, we describe recent updates to the clinical criteria of various disorders sharing clinical symptoms with parkinsonism.

Pathophysiological Mechanisms Underlying Idiopathic Normal Pressure Hydrocephalus: A Review of Recent Insights

The pathophysiologic mechanisms underpinning idiopathic normal pressure hydrocephalus (iNPH), a clinically diagnosed dementia-causing disorder, continue to be explored. An increasing body of evidence implicates multiple systems in the pathogenesis of this condition, though a unifying causative etiology remains elusive. Increased knowledge of the aberrations involved has shed light on the iNPH phenotype and has helped to guide prognostication for treatment with cerebrospinal fluid diversion. In this review, we highlight the central role of the cerebrovasculature in pathogenesis, from hydrocephalus formation to cerebral blood flow derangements, blood-brain barrier breakdown, and glymphatic pathway dysfunction. We offer potential avenues for increasing our understanding of how this disease occurs.

Treatment-responsive Holmes tremor in a child with low-pressure hydrocephalus: video case report and systematic review of the literature

OBJECTIVE

Holmes tremor (HT) is a rare and debilitating movement disorder comprising both rest and action tremor, and it is known for its resistance to treatment. Its most common causes include ischemic or hemorrhagic insults and trauma. Mechanistically, the combined rest and action tremor is thought to require a double lesion of both the dopaminergic nigrostriatal system and the dentatorubrothalamic pathways, often near the midbrain where both pathways converge. The aim of this study was to characterize HT as a presenting sign in cases of hydrocephalus and to discuss potential pathomechanisms, clinical presentations, and treatment options.

METHODS

MEDLINE and Web of Science were searched for cases of HT with hydrocephalus from database inception to August 2021, and these were compiled along with the authors' own unique case of treatment-responsive HT in a child with low-pressure obstructive hydrocephalus secondary to a tectal tumor. Patient characteristics, presenting signs/symptoms, potential precipitating factors, interventions, and patient outcomes were recorded.

RESULTS

Nine patients were identified including the authors' video case report. All patients had a triventriculomegaly pattern with at least a component of obstructive hydrocephalus, and 4 patients were identified as having low-pressure hydrocephalus. Parinaud's syndrome and bradykinesia were the most commonly associated signs. Levodopa and CSF diversion were the most commonly used and effective treatments for HT in this population. This review was not registered and did not receive any funding.

CONCLUSIONS

HT is a poorly understood and probably underrecognized presentation of hydrocephalus that is difficult to treat, limiting the strength of the evidence in this review. Treatment options include CSF diversion, antiparkinsonian agents, antiepileptic agents, deep brain stimulation, and MR-guided focused ultrasound, and aim toward the nigrostriatal and dentatorubrothalamic pathways hypothesized to be involved in its pathophysiology.

Levodopa-responsive Parkinsonism Caused by Recurrence of Large Basilar-tip Aneurysm after Stent-assisted Coil Embolization: A Case Report

Aneurysms of the large basilar artery (BA) occasionally cause cranial nerve palsy and motor disorder through mass effect. Since 1967, five cases of cerebral aneurysm leading to parkinsonism have been reported. Herein, we describe a rare case of progressive parkinsonism caused by the recurrence of a large aneurysm of the basilar tip after stent-assisted coil embolization. A 66-year-old man visited our hospital with an asymptomatic large aneurysm (maximum diameter, 21 mm) of the BA tip. Magnetic resonance imaging (MRI) revealed no perianeurysmal edema. Coil embolization with a Y-configuration stent with cross-placement was performed. Although thrombus formation occurred and the perforator infarction was complicated, complete occlusion was achieved. Three months later, the patient developed progressive and severe parkinsonism. MRI revealed mild enlargement of the aneurysm and perianeurysmal mesencephalic edema with minor neck recurrence. A trial administration of levodopa and additional stent-assisted coil embolization were performed. Levodopa dramatically improved parkinsonism; thus, the patient’s symptoms were controlled by a continuous levodopa regimen. In a large BA-tip aneurysm patient, moderate regrowth and minor neck recurrence occurred after initial treatment, and chronic compression of the midbrain caused secondary parkinsonism. In such cases, it is important to consider levodopa administration and therapeutic strategies to prevent recurrence or regrowth.

Global Rostral Midbrain Syndrome (GRMS) and Corpus callosum infarction in the context of shunt overdrainage

We report 3 cases of Global rostral midbrain syndrome (GRMS) and Corpus Callosum (CC) infarction, in the context of hydrocephalus followed by shunt dysfunction and slit ventricles. Prior shunt implantation had been indicated for adult-onset hydrocephalus secondary to aqueductal stenosis of varying causes. All three patients had been stable for months before developing repeated shunt dysfunctions, ultimately progressing to parkinsonism, Parinaud syndrome, akinetic mutism, pyramidal signs, cognitive impairment, CC infarction and slit ventricles, in the context of CSF overdrainage. Parkinsonism-related symptoms responded to dopa in all cases, but Parinaud syndrome and cognitive impairment persisted. Although GRMS has been described in the context of a transtentorial pressure gradient after shunt blockage, in these three cases with similar clinical presentation, reverse transtentorial pressure gradient and slit ventricles due to shunt overdrainage was the likely cause. The authors discuss the role of CC infarction and provide a detailed analysis after gathering previously described data, to unify information under a recognizable clinical entity and better understand the underlying pathophysiology, treatment options and outcome.

Parkinsonism and cerebrospinal fluid disorders

BACKGROUND

Although various motor manifestations can be seen in patients with cerebrospinal fluid (CSF) disorders, such as hydrocephalus or intracranial hypotension, the clinical presentation with parkinsonism is not clearly elucidated.

METHODS

We searched the literature for studies describing the occurrence of parkinsonism in subjects with normal pressure hydrocephalus (NPH), obstructive hydrocephalus, and intracranial hypotension. We analyzed the clinical presentation (particularly with respect to bradykinesia, rigidity, rest tremor, and gait disturbance/postural instability) as well as the response to treatment.

RESULTS

Parkinsonism was most commonly reported in NPH patients. Although gait disturbance/postural instability is a well-known motor symptom of NPH, other cardinal signs include upper limb involvement or asymmetric presentation. As for obstructive hydrocephalus, parkinsonism was mainly observed in subjects with aqueductal stenosis and more often after shunt surgery. Patients with NPH or obstructive hydrocephalus rarely improved with levodopa therapy, while most subjects only improved with shunt surgery. Although the mechanism is still controversial, a functional involvement of nigrostriatal pathway has been hypothesized based on imaging studies and case reports. Brain imaging is also helpful for atypical cases of intracranial hypotension presenting with parkinsonism. Parkinsonism improved after treatment in such cases as well.

CONCLUSIONS

Studies exploring the relationship between CSF disorders and parkinsonism are mainly descriptive and their quality is generally poor. However, considering that these disorders can be treated, clinicians' awareness of the differential diagnosis is important and future studies better exploring the underlying pathophysiological mechanisms are warranted. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.

The etiopathogenetic and pathophysiological spectrum of parkinsonism

Parkinsonism is a syndrome characterized by bradykinesia, rigidity, and tremor. Parkinsonism is a common manifestation of Parkinson's disease and other neurodegenerative diseases referred to as atypical parkinsonism. However, a growing body of clinical and scientific evidence indicates that parkinsonism may be part of the phenomenological spectrum of various neurological conditions to a greater degree than expected by chance. These include neurodegenerative conditions not traditionally classified as movement disorders, e.g., dementia and motor neuron diseases. In addition, parkinsonism may characterize a wide range of central nervous system diseases, e.g., autoimmune diseases, infectious diseases, cerebrospinal fluid disorders (e.g., normal pressure hydrocephalus), cerebrovascular diseases, and other conditions. Several pathophysiological mechanisms have been identified in Parkinson's disease and atypical parkinsonism. Conversely, it is not entirely clear to what extent the same mechanisms and key brain areas are also involved in parkinsonism due to a broader etiopathogenetic spectrum. We aimed to provide a comprehensive and up-to-date overview of the various etiopathogenetic and pathophysiological mechanisms of parkinsonism in a wide spectrum of neurological conditions, with a particular focus on the role of the basal ganglia involvement. The paper also highlights potential implications in the diagnostic approach and therapeutic management of patients. This article is part of the Special Issue "Parkinsonism across the spectrum of movement disorders and beyond" edited by Joseph Jankovic, Daniel D. Truong and Matteo Bologna.

Parkinsonism reversed from treatment of pineal non-germinomatous germ cell tumor

Background:

Parkinsonism is a rare complication of non-germinomatous germ cell tumors (NGGCTs) arising from the pineal region.

Case Description:

We describe a 23-year-old man who presented with Parinaud syndrome, fatigue, and hypersomnia that were caused by a pineal region NGGCT with yolk sac component and an initial α-fetoprotein (AFP) of 1011.0 ng/ml. MRI revealed that the tumor was causing 10 mm of midline shift and compressing the cerebral aqueduct, the left thalamus, and the midbrain. Obstructive hydrocephalus was relieved by ventriculoperitoneal shunting. Six cycles of induction chemotherapy with ifosfamide, carboplatin, and etoposide reduced tumor size and decreased AFP levels in both serum and cerebrospinal fluid. Following the first cycle, the patient developed asymmetric, bilateral Parkinsonism consisting of bradykinesia, bradyphrenia, facial hypomimia, drooling, and dysphagia. Levodopa, amantadine, and methylphenidate were administered and resulted in symptom improvement. Second look neurosurgery revealed residual yolk sac tumor and a second induction regimen of gemcitabine, paclitaxel, and oxaliplatin was administered for rising AFP. The patient eventually received an autologous bone marrow transplant using a regimen of high-dose carboplatin, thiotepa, and etoposide with concomitant colony-stimulating factor and romiplostim support followed by consolidative proton craniospinal radiotherapy. Posttreatment head MRI showed that no evidence of tumor growth and serum AFP was within normal limits. His Parkinsonism eventually resolved and he was weaned off all dopaminergic drugs.

Conclusion:

Bilateral Parkinsonism from NGGCT in this patient is probably caused by pressure on nigrostriatal tracts, substantia nigra, or both. The Parkinsonian symptoms can be reversed by aggressive treatment of the tumor and administration of dopaminergic drugs.

Clinical Outcome and Striatal Dopaminergic Function After Shunt Surgery in Patients With Idiopathic Normal Pressure Hydrocephalus

OBJECTIVE

To determine changes in clinical features and striatal dopamine reuptake transporter (DAT) density after shunt surgery in patients with idiopathic normal pressure hydrocephalus (iNPH).

METHODS

Participants with probable iNPH were assessed at baseline by means of clinical rating scales, brain MRI, and SPECT with [¹²³I]-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane (FP-CIT). Levodopa responsiveness was also evaluated. Patients who did or did not undergo lumboperitoneal shunt were clinically followed up and repeated SPECT after 2 years.

RESULTS

We enrolled 115 patients with iNPH. Of 102 patients without significant levodopa response and no signs of atypical parkinsonism, 92 underwent FP-CIT SPECT (58 also at follow-up) and 59 underwent surgery. We identified a disequilibrium subtype (phenotype 1) and a locomotor subtype (phenotype 2) of higher-level gait disorder. Gait impairment correlated with caudate DAT density in both phenotypes, whereas parkinsonian signs correlated with putamen and caudate DAT binding in patients with phenotype 2, who showed more severe symptoms and lower striatal DAT density. Gait and caudate DAT binding improved in both phenotypes after surgery (p < 0.01). Parkinsonism and putamen DAT density improved in shunted patients with phenotype 2 (p < 0.001). Conversely, gait, parkinsonian signs, and striatal DAT binding worsened in patients who declined surgery (p < 0.01).

CONCLUSIONS

This prospective interventional study highlights the pathophysiologic relevance of striatal dopaminergic dysfunction in the motor phenotypic expression of iNPH. Absence of levodopa responsiveness, shunt-responsive parkinsonism, and postsurgery improvement of striatal DAT density are findings that corroborate the notion of a reversible striatal dysfunction in a subset of patients with iNPH.

Neurocysticercosis and movement disorders: A literature review

Neurocysticercosis (NCC) is a specific form of cysticercosis that affects the central nervous system. It is caused by the tapeworm Taenia solium, which is often found in pigs. NCC is considered one of the “great simulator/mimickers” of other diseases. In this context, movement disorders (MDs) can occur in a small percentage of individuals with NCC. This review aims to evaluate the clinicoepidemiological profile, pathological mechanisms, and historical features of NCC-associated MD. Relevant reports in six databases were identified and assessed by two reviewers without language restriction. A total of 71 reports containing 148 individuals who developed an MD related to NCC were identified. NCC-associated MD included parkinsonism (n = 47), ataxia (n = 32), chorea (n = 18), dystonia (n = 13), tremor (n = 8), myokymia (n = 6), myoclonus (n = 4), ballism (n = 1), tics (n = 1), and others (n = 18). The mean and median ages were 36.58 (standard deviation: 20.51) and 35 years (age range: 1–88 years), respectively. There was a slight predominance of female sex (52.17%). On follow-up, 58.90% of the individuals had a full recovery; two deaths were reported. We believe that the majority of cases reported were only diagnosed because patients had classical clinical manifestations generally investigated by neuroimaging, resulting in incidental findings suggestive of NCC, which were later supported by laboratory examinations. Therefore, the association between NCC and MD is probably underreported. Clinicians should be wary of this association, mainly in endemic areas for cysticercosis.

A comprehensive clinico-radiological, neuropsychological and biomechanical analysis approach to patients with idiopathic normal pressure hydrocephalus

BACKGROUND

A systematic approach to patients with suspected idiopathic normal pressure hydrocephalus (iNPH) is essential to recognize the subset of patients who may benefit from ventriculoperitoneal shunt surgery (VPS). Quantitative biomechanical analysis of gait and balance (QBAGB) may help objectify the response to the cerebrospinal fluid tap test (CSF-TT) and VPS outcome after 3 months and support identification of candidates for VPS.

METHODS

We retrospectively reviewed data from all patients with probable iNPH who 1) underwent clinico-radiological and neuropsychological assessments using validated scales (iNPH Scale and iNPH Radscale) at our centre in the period from January to December 2018; and 2) had completed QBAGB before CSF-TT ('baseline'), shortly after CSF-TT, and at three months after either VPS or conservative treatment.

RESULTS

At the time-points 'after CSF-TT' and '3 months', patients with iNPH and VPS (n = 11) significantly improved on the Kiefer Scale score, iNPH Scale total score and gait domain score, as well as in gait velocity and step length measured by QBAGB. In contrast, patients without surgery (n = 10) had unchanged iNPH Scale scores and motor performance throughout. Using data from all patients, we calculated cut-off levels for substantial improvements in gait velocity, step length, and the iNPH Scale domain gait score at the time-point 'after CSF-TT'.

CONCLUSION

QBAGB helps to objectify the response to CSF-TT to select candidates for VPS and corroborates clinico-radiological and neuropsychological data derived from validated scales. The QBAGB cut-off values for substantial improvement after CSF-TT need further elucidation in larger, preferably prospective studies.

iNPH with parkinsonism: response to lumbar CSF drainage and ventriculoperitoneal shunting

OBJECTIVES

To evaluate clinical response after external lumbar drainage (ELD) and ventriculoperitoneal shunting (VPS) in a cohort of patients with idiopathic normal pressure hydrocephalus associated with parkinsonism (iNPH-P), considering parkinsonism as clinical primary outcome.

METHODS

Patients underwent long-term 72-h intracranial pressure-controlled CSF ELD. Clinical motor response before and after ELD was evaluated using changes in UPDRS-ME as outcome measure. A standardized cognitive assessment was also performed. iNPH-P patients who underwent VPS were clinically followed-up after surgery.

RESULTS

Fourteen iNPH-P patients (age: 69.3 ± 11.6 years) were studied. The time of evaluation after ELD removal was 3.5 ± 1.8 days. We observed a significant motor improvement after the drainage in eight (57.1%) patients. Percent clinical motor response was 18.4 ± 6.7%. Twelve (85.7%) patients underwent VPS. Nine patients were examined after surgery at 31.6 ± 7 months. Four (44.4%) patients presented a clinically detectable improvement in motor response after VPS. No significant changes in cognitive performances were detected.

CONCLUSIONS

A clinically detectable motor response on parkinsonian signs was observed in a consistent part of iNPH-P patients few days after ELD as well as over two and half years after VPS. Parkinsonism should be considered as outcome measure for the clinical management of patients with iNPH-P.

Is DAT imaging abnormality in normal pressure hydrocephalus always suggestive of degeneration?

Idiopathic normal pressure hydrocephalus (iNPH) is a debated entity with controversial pathogenesis, diagnostic criteria, and predictors of response after ventriculoperitoneal shunt (VPS). Parkinsonian signs are frequently reported in the clinical picture, sometimes due to the coexistence of an underlying neurodegenerative parkinsonism and sometimes in the absence thereof. To distinguish these two scenarios is crucial, since they may carry different long-term response to CSF drainage. ¹²³I-FP-CIT-SPECT was believed to be helpful in this regard, however its role in predicting surgical outcome has been disputed. We illustrate a patient presented with gait disturbance, urinary incontinence, and asymmetrical parkinsonian signs, who underwent a 3T brain MRI and a ¹²³I-FP-CIT-SPECT. VPS was performed. The patient repeated a ¹²³I-FP-CIT-SPECT, 18 months after the operation, and was clinically followed up for 24 months. Our patient displayed clinical and radiological criteria for iNPH and an abnormal asymmetrical uptake in ¹²³I-FP-CIT-SPECT, consistent with her asymmetrical parkinsonism. However, the organization of the substantia nigra studied with iron-sensitive sequences in 3T brain MRI scan appeared intact. The patient revealed an improvement both clinically and in ¹²³I-FP-CIT-SPECT at postsurgical follow-up. Our report suggests that abnormal ¹²³I-FP-CIT-SPECT may not necessarily reveal an overlap with neurodegenerative parkinsonism; its partial reversibility may suggest that the mechanical effect exerted on the striatum by ventriculomegaly ultimately leads to downregulation of dopaminergic transporters which may improve after VPS.

Gaps, Controversies, and Proposed Roadmap for Research in Normal Pressure Hydrocephalus

Idiopathic normal pressure hydrocephalus is considered common but remains underinvestigated. There are no uniformly accepted diagnostic criteria and therapeutic guidelines. We summarize the accumulated evidence regarding the definition, pathophysiology, diagnosis, and treatment of idiopathic normal pressure hydrocephalus, highlighting the many gaps and controversies, including diagnostic challenges, the frequent association with neurodegeneration and vascular disease, and the many unknowns regarding patient selection and outcome predictors. A roadmap to fill these gaps and solve the controversies around this condition is also proposed. More evidence is required with respect to diagnostic criteria, the value of ancillary testing, prospective population-based studies and novel trial designs. Furthermore, a need exists to develop new advanced options in shunt technology. © 2020 International Parkinson and Movement Disorder Society.

Investigating the Levels of Brain-Specific Proteins in Hydrocephalus Patients

BACKGROUND

Hydrocephalus, a common brain disorder in children, can cause permanent brain damage. A timely diagnosis of this disorder is crucial.

OBJECTIVE

The aim of this study was to evaluate the levels of S-100, CK-18, and NSE brainspecific proteins in patients with hydrocephalus. We examined the levels of these proteins in the blood samples of hydrocephalic patients.

METHODS

The study was conducted on the hydrocephalus (n = 31) patients and a healthy control group (n = 30). A Receiver Operating Characteristic (ROC) curve was used to assess the validity of the NSE, CK-18, and S100B to differentiate between the hydrocephalus and the control groups. The suitability of the data to the normal distribution was tested with the Shapiro Wilk test, and the Student t-test was used to compare the characteristics of the normal distribution in two independent groups. The individuals in the hydrocephalus and control groups had similar values in terms of age, height, and weight.

RESULTS

It was observed that NSE, CK-18, and S100B mean values of the individuals in the hydrocephalus group were significantly higher than NSE, CK-18, and S100B mean values of the control group.

CONCLUSION

Experiments have shown that the levels of these proteins increase significantly in hydrocephalus patients compared to the healthy group. These three parameters can be considered as important markers in the diagnosis of hydrocephalus.

Areas of white matter hyperintensities and motor symptoms of Parkinson disease

OBJECTIVE

To determine whether deep white matter and periventricular hyperintensities affect the motor symptoms of Parkinson disease (PD) differently, we analyzed MRI and dopamine transporter imaging.

METHODS

We analyzed the medical records of patients with de novo PD who underwent dopamine transporter PET scanning and MRI at their first visit. Deep white matter and periventricular hyperintensities were scored with a visual rating scale, and motor symptoms were assessed by Unified Parkinson's Disease Rating Scale motor score and tremor, rigidity, bradykinesia, and axial symptom subscores. The influence of white matter hyperintensity on motor symptoms was explored using multivariable linear regression models.

RESULTS

A total of 93 patients (mean age, 67.2 ± 9.9 years; 44 male) were included and the mean motor score was 25.0 ± 10.8. Subscores for bradykinesia and axial symptoms were correlated with both deep white matter and periventricular hyperintensities scores. Multivariable linear regression models revealed that deep white matter hyperintensities score was significantly associated with subscore for bradykinesia and periventricular hyperintensities score was associated with subscores for bradykinesia and axial symptoms after adjusting for putaminal dopamine transporter availability and clinical factors.

CONCLUSIONS

These results demonstrate that deep white matter hyperintensities are associated with bradykinesia and periventricular hyperintensities are associated with bradykinesia and axial symptoms in patients with PD independently of the severity of dopaminergic depletion.

Quantitative Gait Analysis and Cerebrospinal Fluid Tap Test for Idiopathic Normal-pressure Hydrocephalus

We investigated gait performance utilizing a quantitative gait analysis for 2 groups: (1) idiopathic normal-pressure hydrocephalus (INPH) patients who had a positive response to the cerebrospinal fluid tap test (CSFTT) and (2) healthy controls. The aims of the study were (1) to analyze the characteristics of gait features, (2) to characterize changes in gait parameters before and after the CSFTT, and (3) to determine whether there was any relationship between stride time and stride length variability and Frontal Assessment Battery (FAB) scores in INPH patients. Twenty-three INPH patients and 17 healthy controls were included in this study. Compared with healthy controls, the gait of INPH patients was characterized by lower velocity, shorter stride length, and more broad-based gait. Patients with INPH had a longer stance phase with increased double-limb support. Variability in stride time and stride length was increased in INPH patients. Stride time and stride length variability were correlated with FAB score. After the CSFTT, gait velocity, stride length, and step width significantly improved. There were significant decreases in stride time and stride length variability. These results suggest that the CSFTT for INPH patients might improve the so-called balance-related gait parameter (ie, step width) as well. Stride time and stride length variability also responded to the CSFTT. Association between FAB scores and both stride time and stride length variability suggests involvement of similar circuits producing gait variability and frontal lobe functions in INPH patients.

Levodopa-responsive parkinsonism in a patient with corticobasal degeneration and bilateral choroid plexus xanthogranulomas

Corticobasal degeneration (CBD) has substantial overlap of clinical features with other neurodegenerative diseases including Parkinson's disease (PD). Its clinical diagnostic accuracy is the lowest among the common neurodegenerative diseases, and its antemortem diagnosis is more challenging when CBD is comorbid with another brain disease. We report an elderly male patient with multiple medical conditions and a family history of essential tremor. He presented with progressive tremor that was initially thought to be essential tremor and later diagnosed as PD despite head computerized tomography showing bilateral intraventricular masses and other minor changes. The clinical diagnosis of PD was supported by his responsiveness to low-dose levodopa. However, postmortem neuropathological examination revealed CBD and bilateral choroid plexus xanthogranulomas with mild ventricular enlargement and multifocal ependymal lining injury presumably due to mild hydrocephalus. CBD is typically levodopa-unresponsive, but hydrocephalus-associated parkinsonism is commonly levodopa-responsive. We raise awareness of the present comorbidity and atypical parkinsonism due to the choroid plexus xanthogranuloma-induced hydrocephalus for the clinical diagnosis and management of parkinsonism.

Atypical Parkinson Syndrome Hiding a Meningioma

A 59-year-old man had developed within a few months walking disorders and rigidity of the left upper limb. I-FP-CIT SPECT/CT was performed in response to the suspicion of atypical parkinsonian syndrome. It showed an anomaly in presynaptic dopaminergic transmission on the right striatum and a voluminous expansive process on CT. MRI revealed an atypical meningioma. The patient had surgery for tumor removal. Later I-FP-CIT SPECT/CT showed normalization of presynaptic dopaminergic transmission on the right striatum.

Pisa syndrome in Idiopathic Normal Pressure Hydrocephalus

INTRODUCTION

Idiopathic Normal Pressure Hydrocephalus (iNPH) is a complex syndrome of ventriculomegaly that can include parkinsonian-like features besides the classical triad of cognitive decline, urinary incontinence, and gait/balance disturbances. Pisa syndrome (PS) is a postural abnormality often associated with parkinsonism and defined as lateral trunk flexion greater than 10° while standing that resolves in the supine position. We reported a case series of classical "fixed" PS and one case of "Metronome" recurrent side-alternating PS in iNPH, displaying opposite electromyographic patterns of paraspinal muscles.

METHODS

Eighty-five iNPH patients were followed longitudinally for at least one year through scheduled clinical and neuropsychological visits.

RESULTS

Five (5.9%) subjects revealed PS. None of them had nigrostriatal dopaminergic involvement detected by [123I]FP-CIT SPECT. Among these patients, four had "fixed" PS, whereas one showed a recurrent side-alternating PS which repeatedly improved after ventriculo-peritoneal shunt and following adjustments of the valve-opening pressure of the shunt system.

DISCUSSION

This is the first case series of PS in iNPH and the first report of "Metronome" PS in iNPH. The prompt response of the abnormal trunk postures through cerebrospinal fluid (CSF) shunt surgery suggests a causative role of an altered CSF dynamics. PS and gait disorders in iNPH could be explained by a direct involvement of cortico-subcortical pathways and subsequent secondary brainstem involvement, with also a possible direct functional damage of the basal ganglia at the postsynaptic level, due to enlargement of the ventricular system and impaired CSF dynamics. The early detection of these cases supports a proper surgical management.

Deconstructing normal pressure hydrocephalus: Ventriculomegaly as early sign of neurodegeneration

Idiopathic normal pressure hydrocephalus (NPH) remains both oversuspected on clinical grounds and underconfirmed when based on immediate and sustained response to cerebrospinal fluid diversion. Poor long-term postshunt benefits and findings of neurodegenerative pathology in most patients with adequate follow-up suggest that hydrocephalic disorders appearing in late adulthood may often result from initially unapparent parenchymal abnormalities. We critically review the NPH literature, highlighting the near universal lack of blinding and controls, absence of specific clinical, imaging, or pathological features, and ongoing dependence for diagnostic confirmation on variable cutoffs of gait response to bedside fluid-drainage testing. We also summarize our long-term institutional experience, in which postshunt benefits in patients with initial diagnosis of idiopathic NPH persist in only 32% of patients at 36 months, with known revised diagnosis in over 25% (Alzheimer's disease, dementia with Lewy bodies, and progressive supranuclear palsy). We postulate that previously reported NPH cases with "dual" pathology (ie, developing a "second" disorder) more likely represent ventriculomegalic presentations of selected neurodegenerative disorders in which benefits from shunting may be short-lived, with a consequently unfavorable risk-benefit ratio. Ann Neurol 2017;82:503-513.

Parkinsonian symptoms in normal pressure hydrocephalus: a population-based study

It may be challenging to differentiate normal pressure hydrocephalus (NPH) from neurodegenerative disorders such as Parkinson's disease. In this population-based study, we wanted to describe the frequency of parkinsonian symptoms among individuals with and without NPH, and whether the motor examination part of the Unified Parkinson's Disease Rating Scale (UPDRS-m) score differs between these groups. Furthermore, we wanted to find out whether there was a relationship between UPDRS-m score, NPH symptoms, and radiological signs of NPH. A sample of 168 individuals over the age of 65 with and without self-reported symptoms of NPH underwent a computerized tomography of the brain and clinical examination, including UPDRS-m to grade parkinsonian symptoms. According to diagnostic guidelines, 38 fulfilled criteria for NPH, whereas 130 had unlikely NPH. Bradykinesia was significantly more common among those with NPH (79%) compared to those with unlikely NPH (32%) (p < 0.001). The corresponding figures for rigidity were 43 vs. 15% (p < 0.001), for postural instability 71 vs. 22% (p < 0.001), and for tremor at rest 5 vs. 6% (not significant). The total UPDRS-m score was significantly higher among individuals with NPH (median = 12) than without (median = 1) and correlated significantly with the degree of NPH symptoms (r = -0.72) and ventriculomegaly (r = 0.31). In this study, parkinsonian symptoms, except resting tremor, were frequent in individuals with NPH and correlated with the severity of NPH symptoms. Asymmetric symptoms were uncommon. We recommend a liberal use of neuroradiological imaging when investigating a patient with parkinsonian features.

The role of diffusion tensor imaging and fractional anisotropy in the evaluation of patients with idiopathic normal pressure hydrocephalus: a literature review

OBJECTIVE Diffusion tensor imaging (DTI) for the assessment of fractional anisotropy (FA) and involving measurements of mean diffusivity (MD) and apparent diffusion coefficient (ADC) represents a novel, MRI-based, noninvasive technique that may delineate microstructural changes in cerebral white matter (WM). For example, DTI may be used for the diagnosis and differentiation of idiopathic normal pressure hydrocephalus (iNPH) from other neurodegenerative diseases with similar imaging findings and clinical symptoms and signs. The goal of the current study was to identify and analyze recently published series on the use of DTI as a diagnostic tool. Moreover, the authors also explored the utility of DTI in identifying patients with iNPH who could be managed by surgical intervention. METHODS The authors performed a literature search of the PubMed database by using any possible combinations of the following terms: "Alzheimer's disease," "brain," "cerebrospinal fluid," "CSF," "diffusion tensor imaging," "DTI," "hydrocephalus," "idiopathic," "magnetic resonance imaging," "normal pressure," "Parkinson's disease," and "shunting." Moreover, all reference lists from the retrieved articles were reviewed to identify any additional pertinent articles. RESULTS The literature search retrieved 19 studies in which DTI was used for the identification and differentiation of iNPH from other neurodegenerative diseases. The DTI protocols involved different approaches, such as region of interest (ROI) methods, tract-based spatial statistics, voxel-based analysis, and delta-ADC analysis. The most studied anatomical regions were the periventricular WM areas, such as the internal capsule (IC), the corticospinal tract (CST), and the corpus callosum (CC). Patients with iNPH had significantly higher MD in the periventricular WM areas of the CST and the CC than had healthy controls. In addition, FA and ADCs were significantly higher in the CST of iNPH patients than in any other patients with other neurodegenerative diseases. Gait abnormalities of iNPH patients were statistically significantly and negatively correlated with FA in the CST and the minor forceps. Fractional anisotropy had a sensitivity of 94% and a specificity of 80% for diagnosing iNPH. Furthermore, FA and MD values in the CST, the IC, the anterior thalamic region, the fornix, and the hippocampus regions could help differentiate iNPH from Alzheimer or Parkinson disease. Interestingly, CSF drainage or ventriculoperitoneal shunting significantly modified FA and ADCs in iNPH patients whose condition clinically responded to these maneuvers. CONCLUSIONS Measurements of FA and MD significantly contribute to the detection of axonal loss and gliosis in the periventricular WM areas in patients with iNPH. Diffusion tensor imaging may also represent a valuable noninvasive method for differentiating iNPH from other neurodegenerative diseases. Moreover, DTI can detect dynamic changes in the WM tracts after lumbar drainage or shunting procedures and could help identify iNPH patients who may benefit from surgical intervention.

Clinical Correlation of Abnormal Findings on Magnetic Resonance Elastography in Idiopathic Normal Pressure Hydrocephalus

BACKGROUND

Idiopathic normal pressure hydrocephalus (iNPH) is a ventriculomegaly syndrome characterized by dementia, urinary incontinence, and gait disturbance, which is potentially reversible after ventriculoperitoneal shunting (VPS). Magnetic resonance elastography (MRE) is an evolving imaging technology that noninvasively measures tissue viscoelasticity. We studied iNPH patients using MRE prior to shunting, compared them with normal controls, and analyzed associations between MRE findings and clinical features, as a pilot assessment of MRE in iNPH.

METHODS

Stiffness values were measured on preoperative MRE in 10 iNPH patients scheduled for VPS and compared with those in 20 age- and sex-matched controls. Stiffness results were correlated with clinical iNPH symptoms.

RESULTS

MRE demonstrated significantly increased stiffness in iNPH in cerebrum (P = 0.04), occipital (P = 0.002), and parietal (P = 0.01) regions of interest (ROIs) and significantly decreased stiffness in periventricular ROIs (P < 0.0001). Stiffness was not significantly different in frontal (P = 0.1) and deep gray ROIs (P = 0.4). Univariate analysis showed associations between preoperative iNPH symptoms and abnormally increased stiffness, including urinary incontinence with cerebrum (P = 0.005), frontal (P = 0.04), and cerebellum (P = 0.03) ROIs, and Parkinsonism with occipital ROI (P = 0.04). Postoperative improvement was associated with increased deep gray stiffness (P = 0.01); failure was associated with increased temporal (P = 0.0002) stiffness.

CONCLUSIONS

Based on the preliminary results of this small, limited analysis, brain stiffness may be altered in iNPH, and these alterations in parenchymal viscoelastic properties may be correlated with clinical symptoms. Increased temporal stiffness may predict surgical failure and potentially suggest an alternative dementing pathology underlying the iNPH-like symptoms. These findings highlight the potential future utility of MRE in iNPH management.

Hydrocephalus in Patient with Multiple System Atrophy: Innocent Bystander or Guilty Party?

Background

Normal pressure hydrocephalus (NPH) is a poorly understood condition, which typically presents with the triad of gait disturbance, urinary incontinence and cognitive decline. Diagnosis of NPH is often challenging due to its varied presentation and overlap with other neurodegenerative diseases including multiple system atrophy (MSA).

Case Report

A 68-year-old male developed rapidly progressive gait difficulty, urinary incontinence and memory impairment. Neurologic examination showed parkinsonism affecting the right side and impaired postural reflexes. Brain MRI showed enlargement of the ventricles and narrowing of the high convexity cerebrospinal fluid (CSF) spaces with relative dilated Sylvian fissure, the supporting features of NPH. 18F-fluorinated-N-3-fluoropropyl-2-b-carboxymethoxy-3-b-(4-iodophenyl) nortropane (¹⁸F-FP-CIT) PET showed decreased FP-CIT binding in the left posterior putamen and ¹⁸F-fluorodeoxyglucose PET showed decreased metabolism in the left basal ganglia, consistent with findings of MSA. CSF removal was performed and the symptoms were improved. The patient underwent ventriculo-peritoneal shunt and his gait and cognition improved.

Conclusions

NPH is a potentially treatable neurological disorder. Therefore, it is necessary to consider the possibility of accompanying NPH when hydrocephalus is present in other neurodegenerative diseases.

Comparison of 3T and 7T susceptibility-weighted angiography of the substantia nigra in diagnosing Parkinson disease

BACKGROUND AND PURPOSE

Standard neuroimaging fails in defining the anatomy of the substantia nigra and has a marginal role in the diagnosis of Parkinson disease. Recently 7T MR target imaging of the substantia nigra has been useful in diagnosing Parkinson disease. We performed a comparative study to evaluate whether susceptibility-weighted angiography can diagnose Parkinson disease with a 3T scanner.

MATERIALS AND METHODS

Fourteen patients with Parkinson disease and 13 healthy subjects underwent MR imaging examination at 3T and 7T by using susceptibility-weighted angiography. Two expert blinded observers and 1 neuroradiology fellow evaluated the 3T and 7T images of the sample to identify substantia nigra abnormalities indicative of Parkinson disease. Diagnostic accuracy and intra- and interobserver agreement were calculated separately for 3T and 7T acquisitions.

RESULTS

Susceptibility-weighted angiography 7T MR imaging can diagnose Parkinson disease with a mean sensitivity of 93%, specificity of 100%, and diagnostic accuracy of 96%. 3T MR imaging diagnosed Parkinson disease with a mean sensitivity of 79%, specificity of 94%, and diagnostic accuracy of 86%. Intraobserver and interobserver agreement was excellent at 7T. At 3T, intraobserver agreement was excellent for experts, and interobserver agreement ranged between good and excellent. The less expert reader obtained a diagnostic accuracy of 89% at 3T.

CONCLUSIONS

Susceptibility-weighted angiography images obtained at 3T and 7T differentiate controls from patients with Parkinson disease with a higher diagnostic accuracy at 7T. The capability of 3T in diagnosing Parkinson disease might encourage its use in clinical practice. The use of the more accurate 7T should be supported by a dedicated cost-effectiveness study.

Hydrocephalic Parkinsonism: lessons from normal pressure hydrocephalus mimics

Background

Hydrocephalus is an under-recognized presentation of progressive supranuclear palsy (PSP) and dementia with Lewy bodies (DLB).

Methods

We 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.

Results

Despite 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.

Conclusions

Early 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.

Electronic supplementary material

The online version of this article (doi:10.1186/2054-7072-1-2) contains supplementary material, which is available to authorized users.