Use of cortical volume to predict response to temporary CSF drainage in patients with idiopathic normal pressure hydrocephalus.

OBJECTIVE: Temporary drainage of CSF with lumbar puncture or lumbar drainage has a high predictive value for identifying patients with suspected idiopathic normal pressure hydrocephalus (iNPH) who may benefit from ventriculoperitoneal shunt insertion. However, it is unclear what differentiates responders from nonresponders. The authors hypothesized that nonresponders to temporary CSF drainage would have patterns of reduced regional gray matter volume (GMV) as compared with those of responders. The objective of the current investigation was to compare regional GMV between temporary CSF drainage responders and nonresponders. Machine learning using extracted GMV was then used to predict outcomes. METHODS: This retrospective cohort study included 132 patients with iNPH who underwent temporary CSF drainage and structural MRI. Demographic and clinical variables were examined between groups. Voxel-based morphometry was used to calculate GMV across the brain. Group differences in regional GMV were assessed and correlated with change in results on the Montreal Cognitive Assessment (MoCA) and gait velocity. A support vector machine (SVM) model that used extracted GMV values and was validated with leave-one-out cross-validation was used to predict clinical outcome. RESULTS: There were 87 responders and 45 nonresponders. There were no group differences in terms of age, sex, baseline MoCA score, Evans index, presence of disproportionately enlarged subarachnoid space hydrocephalus, baseline total CSF volume, or baseline white matter T2-weighted hyperintensity volume (p > 0.05). Nonresponders demonstrated decreased GMV in the right supplementary motor area (SMA) and right posterior parietal cortex as compared with responders (p < 0.001, p < 0.05 with false discovery rate cluster correction). GMV in the posterior parietal cortex was associated with change in MoCA (r2 = 0.075, p < 0.05) and gait velocity (r2 = 0.076, p < 0.05). Response status was classified by the SVM with 75.8% accuracy. CONCLUSIONS: Decreased GMV in the SMA and posterior parietal cortex may help identify patients with iNPH who are unlikely to benefit from temporary CSF drainage. These patients may have limited capacity for recovery due to atrophy in these regions that are known to be important for motor and cognitive integration. This study represents an important step toward improving patient selection and predicting clinical outcomes in the treatment of iNPH.

Reducing the risks of proximal and distal shunt failure in adult hydrocephalus: a shunt outcomes quality improvement study.

OBJECTIVE: Patient outcomes of ventriculoperitoneal (VP) shunt surgery, the mainstay treatment for hydrocephalus in adults, are poor because of high shunt failure rates. The use of neuronavigation or laparoscopy can reduce the risks of proximal or distal shunt catheter failure, respectively, but has less independent effect on overall shunt failures. No adult studies to date have combined both approaches in the setting of a shunt infection prevention protocol to reduce shunt failure. The goal of this study was to determine whether combining neuronavigation and laparoscopy with a shunt infection prevention strategy would reduce the incidence of shunt failures in adult hydrocephalic patients. METHODS: Adult patients (age ≥ 18 years) undergoing VP shunt surgery at a tertiary care institution prior to (pre-Shunt Outcomes [ShOut]) and after (post-ShOut) the start of a prospective continuous quality improvement (QI) study were compared. Pre-ShOut patients had their proximal and distal catheters placed under conventional freehand approaches. Post-ShOut patients had their shunts inserted with neuronavigational and laparoscopy assistance in placing the distal catheter in the perihepatic space (falciform technique). A shunt infection reduction protocol had been instituted 1.5 years prior to the start of the QI initiative. The primary outcome of interest was the incidence of shunt failure (including infection) confirmed by standardized criteria indicating shunt revision surgery. RESULTS: There were 244 (115 pre-ShOut and 129 post-ShOut) patients observed over 7 years. With a background of shunt infection prophylaxis, combined neuronavigation and laparoscopy was associated with a reduction in overall shunt failure rates from 37% to 14%, 45% to 22%, and 51% to 29% at 1, 2, and 3 years, respectively (HR 0.44, p < 0.001). Shunt infection rates decreased from 8% in the pre-ShOut group to 0% in the post-ShOut group. There were no proximal catheter failures in the post-ShOut group. The 2-year rates of distal catheter failure were 42% versus 20% in the pre- and post-ShOut groups, respectively (p < 0.001). CONCLUSIONS: Introducing a shunt infection prevention protocol, placing the proximal catheter under neuronavigation, and placing the peritoneal catheter in the perihepatic space by using the falciform technique led to decreased rates of infection, distal shunt failure, and overall shunt failure.

Acute low-pressure hydrocephalus: a case series and systematic review of 195 patients.

OBJECTIVE: Acute low-pressure hydrocephalus (ALPH) is characterized by clinical manifestations of an apparent raised intracranial pressure (ICP) and ventriculomegaly despite measured ICP that is below the expected range (i.e., typically ≤ 5 cm H2O). ALPH is often refractory to standard hydrocephalus intervention protocols and the ICP paradox commonly leads to delayed diagnosis. The aim of this study was to characterize ALPH and develop an algorithm to facilitate diagnosis and management for patients with ALPH. METHODS: EMBASE, MEDLINE, and Google Scholar databases were searched for ALPH cases from its first description in 1994 until 2019. Cases that met inclusion criteria were pooled with cases managed at the authors' institution. Patient characteristics, presenting signs/symptoms, precipitating factors, temporizing interventions, definitive treatment, and patient outcomes were recorded. RESULTS: There were 195 patients identified, with 42 local and 153 from the literature review (53 pediatric patients and 142 adults). Decreased level of consciousness was the predominant clinical sign. The most common etiologies of hydrocephalus were neoplasm and hemorrhage. While the majority of ALPH occurred spontaneously, 39% of pediatric patients had previously undergone a lumbar puncture. Prior to ALPH diagnosis, 92% of pediatric and 39% of adult patients had a ventricular shunt in situ. The most common temporizing intervention was subatmospheric CSF drainage. The majority of patients underwent a shunt insertion/revision or endoscopic third ventriculostomy as definitive ALPH treatment. Although the mortality rate was 11%, 83% of pediatric and 49% of adult patients returned to their pre-ALPH neurological functional status after definitive treatment. Outcomes were related to both the severity of the underlying neurosurgical disease causing the hydrocephalus and the efficacy of ALPH treatment. CONCLUSIONS: ALPH is an underrecognized variant phenotype of hydrocephalus that is associated with multiple etiologies and can be challenging to treat as it frequently does not initially respond to standard strategies of CSF shunting. With early recognition, ALPH can be effectively managed. A management algorithm is provided as a guide for this purpose.

Long-Term Outcomes of Endoscopic Third Ventricle Colloid Cyst Resection: Case Series With a Proposed Grading System.

BACKGROUND: Endoscopic resection of colloid cysts has gained recent widespread practice. However, reported complication and recurrence rates are variable, possibly, in part, because of a lack of consistency with reporting of the extent of cyst capsule removal. OBJECTIVE: To present the long-term outcomes of endoscopic resection of third ventricle colloid cysts without complete capsule removal and propose a grading system to allow consistent description of surgical outcomes. METHODS: A retrospective review of 74 patients who underwent endoscopic resection of symptomatic third ventricle colloid cysts between 1995 and 2018 was performed. Kaplan-Meier analyses were used to assess recurrence-free survival rates. RESULTS: Median patient age and cyst diameter were 48.0 (13.0-80.0) yr and 12.0 (5.0-27.0) mm, respectively. Complete emptying of cyst contents with capsule coagulation was achieved in 73 (98.6%) patients. All patients improved or remained stable postoperatively, with a median follow-up duration of 10.3 (0.3-23.7) yr. Radiographic recurrence occurred in 6 (8.1%) patients after their initial surgery, 5 (6.8%) of whom underwent redo endoscopic resection. No major complications or mortality was encountered at primary or recurrence surgery. CONCLUSION: Endoscopic resection of third ventricle colloid cysts without emphasizing complete capsule removal is a viable option for successfully treating colloid cysts of the third ventricle. Long-term follow-up demonstrates that it is associated with low risks of complications, morbidity, mortality, and recurrence. The proposed extent of the resection grading scheme will permit comparison between the different surgical approaches and facilitate the establishment of treatment guidelines for colloid cysts.

Correction: Age-specific global epidemiology of hydrocephalus: Systematic review, metanalysis and global birth surveillance.

[This corrects the article DOI: 10.1371/journal.pone.0204926.].

Age-specific global epidemiology of hydrocephalus: Systematic review, metanalysis and global birth surveillance.

BACKGROUND: Hydrocephalus is a debilitating disorder, affecting all age groups. Evaluation of its global epidemiology is required for healthcare planning and resource allocation. OBJECTIVES: To define age-specific global prevalence and incidence of hydrocephalus. METHODS: Population-based studies reporting prevalence of hydrocephalus were identified (MEDLINE, EMBASE, Cochrane, and Google Scholar (1985-2017)). Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Two authors reviewed abstracts, full text articles and abstracted data. Metanalysis and meta-regressions were used to assess associations between key variables. Heterogeneity and publication bias were assessed. Main outcome of interest was hydrocephalus prevalence among pediatric (≤ 18 years), adults (19-64 years), and elderly (≥ 65) patients. Annual hydrocephalus incidence stratified by country income level and folate fortification requirements were obtained (2003-2014) from the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR). RESULTS: Of 2,460 abstracts, 52 met review eligibility criteria (aggregate population 171,558,651). Mean hydrocephalus prevalence was 85/100,000 [95% CI 62, 116]. The prevalence was 88/100,000 [95% CI 72, 107] in pediatrics; 11/100,000 [95% CI 5, 25] in adults; and 175/100,000 [95% CI 67, 458] in the elderly. The ICBDSR-based incidence of hydrocephalus diagnosed at birth remained stable over 11 years: 81/100,000 [95% CI 69, 96]. A significantly lower incidence was identified in high-income countries. CONCLUSION: This systematic review established age-specific global hydrocephalus prevalence. While high-income countries had a lower hydrocephalus incidence according to the ICBDSR registry, folate fortification status was not associated with incidence. Our findings may inform future healthcare resource allocation and study.