Luciano, Mark G.

OBJECTIVE The management of excess CSF in patients with hydrocephalus typically requires using a shunt to divert CSF. Unfortunately, there is a high rate of shunt failure despite improvements in device components and insertion techniques. Reoperation is frequently necessary, which contributes to patient harm and increased healthcare costs. While factors affecting shunt failure are well defined in the pediatric population, information regarding adults is lacking. The authors undertook a systematic review and meta-analysis to determine how shunt failure in the adult population is reported and investigated the etiologies of shunt failure. METHODS This review is reported according to PRIMSA and utilized the MEDLINE, Embase, and Google Scholar databases. Abstracts were screened by two independent reviewers, and data were extracted in duplicate by two independent reviewers. Statistical analyses were performed using SPSS and Stata. RESULTS The pooled rates of shunt failure were 10% (95% CI 5%–15%) in studies with a mean follow-up time of less than 1 year, 12% (95% CI 8%–14%) with a follow-up time between 1 and 2 years, and 32% in studies with a follow-up time of 2 years or greater (95% CI 19%–43%). The pooled rate of failure was 17% across all studies. The most common cause of shunt failure was obstruction at 3.0% (95% CI 2%–4%), accounting for 23.2% of shunt failures. Infection was the second most common at 2.8% (95% CI 2%–3%), accounting for 22.5% of shunt failures. The most common location of shunt failure was the distal catheter, with a failure rate of 4.0% (95% CI 3%–5%), accounting for 33.4% of shunt failures. The definition of shunt failure was heterogeneous and varied depending on institutional practices. The combination of symptoms with either CT or MRI was the most frequently reported method for assessing shunt failure. CONCLUSIONS Important variation regarding how to define, investigate, and report shunt failure was identified. The overall shunt failure rate in adults is at least 32% after 2 years, which, while lower than that typically reported in the pediatric population, is significant. The most common causes of shunt failure in adults are infection and obstruction. The most common site of failure occurred at the distal catheter, highlighting the need to develop strategies to both report and mitigate distal shunt failure in adult shunt patients.

Background While venous congestion in the peripheral vasculature has been described and accepted, intracranial venous congestion remains poorly understood. The characteristics, pathophysiology, and management of cerebral venous stasis, venous hypertension and venous congestion remain controversial, and a unifying conceptual schema is absent. The cerebral venous and lymphatic systems are part of a complex and dynamic interaction between the intracranial compartments, with interplay between the parenchyma, veins, arteries, cerebrospinal fluid, and recently characterized lymphatic-like systems in the brain. Each component contributes towards intracranial pressure, occupying space within the fixed calvarial volume. This article proposes a framework to consider conditions resulting in brain and neck venous congestion, and seeks to expedite further study of cerebral venous diagnoses, mechanisms, symptomatology, and treatments. Methods A multi-institution retrospective review was performed to identify unique patient cases, complemented with a published case series to assess a spectrum of disease states with components of venous congestion affecting the brain. These diseases were organized according to anatomical location and purported mechanisms. Outcomes of treatments were also analyzed. Illustrative cases were identified in the venous treatment databases of the authors. Conclusion This framework is the first clinically structured description of venous pathologies resulting in intracranial venous and cerebrospinal fluid hypertension. Our proposed system highlights unique clinical symptoms and features critical for appropriate diagnostic work-up and potential treatment. This novel schema allows clinicians effectively to approach cases of intracranial hypertension secondary to venous etiologies, and furthermore provides a framework by which researchers can better understand this developing area of cerebrovascular disease.