BACKGROUND AND OBJECTIVES: Ventriculoperitoneal shunt (VPS) placement is a common treatment for idiopathic normal pressure hydrocephalus (iNPH), but patients may require VPS revision. This study aims to evaluate the effectiveness of a standardized VPS placement protocol by comparing indications and rates of shunt revision compared with a historical institutional cohort. METHODS: All patients treated with VPS for “suspected” iNPH at a tertiary care center between January 2000 and January 2023 were retrospectively reviewed and divided into temporally distinct historical (before 2017) and standardized (after 2017) cohorts. Cumulative incidence and timing of VPS revision were compared using competing risks analyses. RESULTS: A total of 561 patients (median age 75.0 years) were identified with 324 (57.8%) in the historical and 237 (42.2%) in the standardized cohorts. Significant variations in surgical technique and shunt hardware were noted between the cohorts. With a median follow-up of 11.4 months for historical and 12.4 months for standardized cohort, shunt revisions occurred in 19.4% and 8.4% of patients in the historical and standardized cohorts, respectively ( P < .001). Revision indications also varied significantly with lower rates of overdrainage ( P < .001), infection ( P < .001), and proximal malfunction ( P = .042) but higher rate of distal malfunction ( P = .03) in the standardized cohort. Notably, no infections were noted in the standardized cohort. CONCLUSION: Risk of shunt revision among iNPH patients may be associated with modifiable factors related to surgical technique and shunt hardware selection. Importantly, no short-term complications such as hemorrhage, infection, or catheter malposition were observed with the standardized protocol. Development and refinement of standardized shunt protocols for iNPH patients should be commonplace to facilitate tracking, identification, and modification of modifiable technical risk factors.
Autonomic Dysfunction and Risk of Mortality in Early‐Onset Parkinson's Disease
Objective Dysautonomia affects many patients with Parkinson's disease and correlates with increased cardiovascular mortality. We describe the frequency and onset time of autonomic dysfunction relative to disease onset in early‐onset Parkinson's disease (EOPD) and explore its association with mortality. Methods We identified all incident Parkinson cases with motor‐symptom onset before age 50 years evaluated at the Mayo Clinic Health System (1990–2022) including sex‐ and age‐matched controls for each patient. Medical record review confirmed clinical diagnosis and assessed the presence and onset of autonomic symptoms, relative to Parkinson onset. Results We included 829 patients with EOPD and 829 healthy controls. The median age at disease onset was 42 years (interquartile range [IQR] = 37–46 years). Autonomic symptoms were present in 63.4% of patients, compared with 27.0% of unaffected controls, and proceeded motor symptoms in 91.4%. Forty‐seven percent of patients with early‐onset Parkinson's disease had constipation, 27.4% had bladder urgency, 19.3% had orthostatic intolerance, and 15.4% had sweat dysfunction. Among male patients, 36.8% had erectile dysfunction. In our EOPD population only, the presence of any autonomic‐impairment symptoms correlated with a 2.71‐fold increased mortality risk; each additional reported symptom increased the relative mortality risk by 50% ( p < 0.001). Patients with constipation or orthostatic intolerance had a 3.22‐ and 2.78‐fold higher mortality than patients without these symptoms. Interpretation Autonomic impairment affects 63.4% of patients with EOPD and carries a 3‐fold higher mortality risk, which increases with every additional autonomic symptom reported. In our cohort, autonomic symptoms appeared most commonly after motor onset, contrasting with prodromal autonomic impairment seen in late‐onset Parkinson's disease (LOPD). ANN NEUROL 2026;99:964–975
The Role of Trendelenburg Positioning for the Acute Symptomatic Management of Spontaneous Intracranial Hypotension
Background Spontaneous intracranial hypotension (SIH) results from cerebrospinal fluid (CSF) leakage due to spinal dural tears or CSF–venous fistulas. Orthostatic headache is the hallmark presentation, though severe downward displacement of the brainstem may lead to altered consciousness or coma. Definitive treatments include targeted epidural blood patches, venous embolization, or surgical repair. Methods This article reviews the role of the Trendelenburg position as a temporizing measure in the acute management of SIH. We describe the correct technique, physiologic rationale, and practical considerations for its application, with attention to both therapeutic and diagnostic utility. Discussion Positioning the patient with the feet elevated above the head can reduce brain sag and provide short-term symptomatic relief while awaiting definitive treatment. Although the Trendelenburg position is widely used in practice, supporting evidence remains limited, and clinicians must be aware of its benefits, indications, and inherent limitations. Its appropriate application may assist in stabilizing patients with acute or severe SIH, particularly those with impaired consciousness, until more definitive interventions are pursued.
The contribution of lumbar puncture opening pressure in the diagnosis of spontaneous intracranial hypotension: A systematic literature review and meta‐analysis
Abstract Objective The objective of this study was to summarize the available evidence regarding the clinical value and trend over time of lumbar cerebrospinal fluid (CSF) opening pressure utilization to diagnose spontaneous intracranial hypotension (SIH). Background CSF opening pressure obtained via lumbar puncture is one of the diagnostic criteria for SIH based on the International Criteria for Headache Disorders, 3rd Edition (ICHD‐3), but it has questionable utility as an initial investigation for diagnosing SIH. Methods The authors performed a systematic literature review and meta‐analysis. PubMed/MEDLINE, Scopus, and Cochrane Library were searched from inception to October 2022. Original studies and case series in English reporting three or more patients with suspected or known SIH and CSF pressure measurement were included. Meta‐analyses and meta‐regression were used to calculate pooled estimates and examine the impact of age, sex, and publication year on outcomes, including CSF pressure < 60 mm CSF, orthostatic headache, and positive findings on brain magnetic resonance imaging (MRI), spinal imaging, and radionuclide studies. Results For every 1‐year increase in the year of publication, the odds of reporting low CSF pressure decreased by 6.20% (adjusted odds ratio [aOR] = 0.94, aOR 95% confidence interval [CI] = [0.90, 0.97], p = 0.001), the odds of reporting a positive brain MRI increased by 4.67% (aOR = 1.05, aOR 95% CI = [1.01, 1.09], p = 0.026), and the odds of reporting orthostatic headache increased by 9.13% (aOR = 1.09, aOR 95% CI = [1.03, 1.15], p = 0.002). Each 1% increase in the percentage of patients with orthostatic headache was associated with a 3.13% increase in the odds of low CSF pressure (aOR = 1.03, aOR 95% CI = [1.01, 1.05], p = 0.003). Similarly, as the percentage of patients with low CSF pressure increased by 1%, there was a 2.53% increase in the odds of orthostatic headache (aOR = 1.03, aOR 95% CI = [1.01, 1.04], p = 0.005). It was estimated that 31.9% of patients with SIH had normal opening pressure (95% CI = [24.0%, 40.8%], prediction interval = [5.0%, 80.5%]). Every 1% increase in the percentage of patients with positive brain MRI was associated with a 5.25% increase in the odds of positive spinal imaging (aOR = 1.05, aOR 95% CI = [1.00, 1.11], p = 0.047). Age and positive radionuclide study did not significantly impact the outcomes measured. The corresponding I 2 for each outcome was reduced by controlling for study‐wide covariates believed to impact the prevalence of each outcome. Sensitivity analyses did not reveal discrepancies in results when studies requiring outcomes of interest were removed. Conclusion Our analysis found that recent studies indicate a reduced reliance on opening pressure for diagnosing SIH. Rather, results suggest an increasing reliance on contrast‐enhanced brain MRI, spine imaging, and clinical features for SIH diagnosis.
A 49-year-old woman presented with a dorsal column-predominant sensory myelopathy secondary to superficial siderosis. She had Marfan syndrome and was found to have dural ectasia. Superficial siderosis results from subpial haemosiderin deposition due to chronic subarachnoid space bleeding, often from a dural pathology, such as a tear. Dural ectasia is common in Marfan syndrome, but superficial siderosis is not. Gait ataxia, often with hearing impairment, is a common clinical presentation of superficial siderosis. Patients may develop myelopathy, here being a pure sensory myelopathy with predominant dorsal column deficit. Meningeal diverticulae and superficial siderosis are both associated with cerebrospinal fluid (CSF) leaks. This patient had dural ectasia and meningeal diverticulae, but the CT myelogram found no CSF leak. Superficial siderosis should be considered in patients with sensory myelopathy. Lumbosacral dural ectasia, or less likely CSF leak, can cause superficial siderosis in people with Marfan syndrome.
Acute and Chronic CSF Dynamics Disorders Are Not the Same: Mechanistic Insights From Postdural Puncture Headache
OBJECTIVE Idiopathic normal pressure hydrocephalus (iNPH) is characterized by gait deterioration, cognitive disturbances, and urinary incontinence. Gait deficits pose safety hazards due to frequent falls, yet objective investigations of gait improvement following ventriculoperitoneal shunt (VPS) placement are limited. Therefore, the aim of this study was to assess objective improvement in gait parameters for patients with iNPH after VPS placement. METHODS All patients treated with a VPS for iNPH by the senior author at a single tertiary care center from December 2017 to January 2023 were retrospectively reviewed. Patients who underwent detailed motion analysis testing before surgery with > 1 follow-up assessment were included. Analyzed parameters included gait velocity, gait cadence, stride length, stride width, gait stability ratio, total support, and single support. Time-dependent linear mixed-effects models and generalized additive mixed-effects models (GAMMs) were used to model short-term and longitudinal gait parameter changes, respectively. RESULTS A total of 212 patients (137 male, median age was 75.2 years) who underwent VPS placement for iNPH were included, with a total of 747 gait analyses performed at a median last-gait analysis follow-up duration of 12.0 months. Statistically significant changes in all gait parameter values were seen between the preoperative time point and first postoperative follow-up (within 3 months) time point (paired Wilcoxon p < 0.001), with a statistically significant majority of patients experiencing improvement (binominal p < 0.0001). Longitudinal analyses using a GAMM showed increased gait velocity, single support, and stride length, with decreased stability ratio, step width, and total support at early time points, while a plateau was achieved around 6 months. CONCLUSIONS A detailed gait analysis demonstrated significant improvements in objective ambulation metrics, particularly in the gait velocity, stride length, and gait stability ratio, following VPS placement in patients with iNPH. Most patients maintained marked improvement from baseline to the last follow-up assessment, although a plateau of the benefit was experienced over longer follow-up.