BACKGROUND: Parkinsonism has been reported in patients with obstructive hydrocephalus (OH) following ventriculoperitoneal shunting (VPS). While levodopa works well, some cases are drug resistant. A few case series have reported that endoscopic third ventriculostomy (ETV) is beneficial, though its mechanism remains unclear. The use of a pathophysiology-reflected marker can aid in the diagnosis and treatment strategy. The authors report a case of parkinsonism due to OH after VPS that improved after ETV in a patient taking levodopa, which was subsequently discontinued.
METHODS: A 52-year-old man who had undergone VPS for OH caused by aqueductal stenosis with a tectal tumor presented with severe consciousness disturbance due to acute hydrocephalus and levodopa-refractory parkinsonism after multiple episodes of shunt malfunction. Magnetic resonance imaging showed an elevation of the floor of the third ventricle. ETV was performed to stabilize the pressure imbalance across the stenosis, and his parkinsonism symptoms improved after long-term rehabilitation, resulting in levodopa discontinuation. His pontomesencephalic angle, the angle between the anterior surface of the midbrain and upper surface of the pons in the midline of the sagittal plane, was significantly decreased.
CONCLUSIONS: The focus in such cases should be on the essence of the pathophysiology for improving the symptoms rather than on easy-to-understand indicators such as ventricle size. https://thejns.org/doi/10.3171/CASE2429.

Early recognition and prompt surgical intervention are crucial in managing giant arachnoid cysts causing obstructive hydrocephalus, as illustrated in this case of a 17-year-old male. Timely treatment can alleviate symptoms and prevent neurologic complications, ensuring favorable outcomes in affected patients.

BACKGROUND: Entrapment of the temporal horn (TH) is rare condition that can lead to increased intracranial pressure, but there is no consensus on a standard treatment. The aim of this study was to conduct a systematic literature review of the reported cases of TH entrapment and describe our operative technique for endoscopic fenestrations of the lateral ventricle into the basal cisterns.
METHODS: We searched the databases Pubmed and Google scholar to find all studies reporting cases of entrapped TH and the subsequent treatment. Additionally, we report two illustrative cases of endoscopic fenestration with a step-by-step description of our surgical technique.
RESULTS: Twenty-nine studies with a total of 67 patients were included in the analysis. The mean age was 36.5 years (SD± 21.9), and the female-to-male ratio was 1.5. The most frequent cause of TH entrapment was post-surgical scarring after tumor surgery (n= 30), and the most commonly reported treatment modality was endoscopic fenestration of the TH (n = 14). We observed an increasing use of endoscopic fenestration over time.
CONCLUSIONS: Entrapped TH is a rare condition often requiring surgical treatment. Neuronavigation-guided endoscopic fenestration of the ventricle into the basal cisterns appears to be a safe, efficient, and device-free technique that has gained importance over the past years.

BACKGROUND: Isolated cerebral mucormycosis is rare in immunocompetent adults and is only sparsely reported to be associated with obstructive hydrocephalus.
METHODS: Here, the authors report a case of obstructive hydrocephalus secondary to central nervous system mucormycosis without other systems or rhino-orbital involvement and its technical surgical management. A 23-year-old, incarcerated, immunocompetent patient with history of intravenous (IV) drug use presented with syncope. Although clinical and radiographic findings failed to elucidate an infectious pathology, endoscopy revealed an obstructive mass lesion at the level of the third ventricle, which, on microbiological testing, was confirmed to be Rhizopus fungal ventriculitis. Perioperative cerebrospinal fluid diversion, endoscopic third ventriculostomy, endoscopic biopsy technique, patient outcomes, and the literature are reviewed here. The patient received intrathecal and IV amphotericin B followed by a course of oral antifungal treatment and currently remains in remission.
CONCLUSIONS: The patient\'s unique presentation and diagnosis of isolated cerebral mucormycosis reveal this pathogen as a cause of ventriculitis and obstructive hydrocephalus in immunocompetent adult patients, even in the absence of infectious sequelae on neuroimaging.

BACKGROUND: Perivascular spaces (PVSs) are spaces in brain parenchyma filled with interstitial fluid surrounding small cerebral vessels. Massive enlargements of PVSs are referred to as \"giant tumefactive perivascular spaces\" (GTPVSs), which can be classified into three types depending on their localization. These lesions are rare, predominantly asymptomatic, and often initially misinterpreted as cystic tumor formations. However, there are several reported cases in which GTPVSs have induced neurological symptoms because of their size, mass effect, and location, ultimately leading to obstructive hydrocephalus necessitating neurosurgical intervention. Presented here are three diverse clinical presentations of GTPVS.
METHODS: Here, the authors observed an asymptomatic case of type 1 GTPVS and two symptomatic cases of type 3 GTPVS, one causing local mass effect and the other hydrocephalus.
CONCLUSIONS: GTPVSs are mostly asymptomatic lesions. Patients without symptoms should be closely monitored, and biopsy is discouraged. Hydrocephalus resulting from GTPVS necessitates surgical intervention. In these cases, third ventriculostomy, shunt implantation, or direct cyst fenestration are surgical options. For patients presenting with symptoms from localized mass effect, a thorough evaluation for potential neurosurgical intervention is imperative. Follow-up in type 3 GTPVS is recommended, particularly in untreated cases. Given the infrequency of GTPVS, definitive guidelines for neurosurgical treatment and subsequent follow-up remain elusive.

BACKGROUND: Neurosarcoidosis occurs symptomatically in 5-10% of patients with sarcoidosis, and hydrocephalus is a rare complication of neurosarcoidosis, with either acute or subacute onset and presenting symptoms related to increased intracranial pressure. It represents a potentially fatal manifestation with a mortality rate of 22% (increased to 75% in case of coexistence of seizures) that requires a prompt initiation of treatment. High-dose intravenous corticosteroid treatment and neurosurgical treatment must be considered in all cases of neurosarcoidosis hydrocephalus.
METHODS: Here we present a case of hydrocephalus in neurosarcoidosis, complicated by generalized seizures, in a 29-year-old Caucasian male patient treated with medical treatment only, with optimal response.
CONCLUSIONS: Since neurosurgery treatment can lead to severe complications, this case report underlines the possibility to undergo only medical treatment in selected cases. Further studies are needed to stratify patients and better identify those eligible for only medical approach.

Emergency physicians are well-versed in managing cardiac arrests, including the diagnostic and therapeutic steps after return of spontaneous circulation. Neurologic emergencies are a common cause of out-of-hospital cardiac arrest and must remain high in the differential diagnosis, as such cases often require specific interventions that may deviate from more common care pathways. Performing a noncontrast head computed tomography (NCHCT) scan after cardiac arrest has been found to change management, although the optimal timing of this imaging is unclear.
This is the case of a young, pregnant woman who presented to the emergency department after cardiac arrest with return of spontaneous circulation in the prehospital setting. She was found to have acute obstructive hydrocephalus on NCHCT, which was later confirmed to be due to a previously undiagnosed colloid cyst of the third ventricle. This acute obstruction resulted in myocardial stunning and, ultimately, cardiac arrest. Although outcomes are often dismal when the cause of arrest is secondary to neurologic catastrophe, this patient survived with completely intact neurologic function. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Although acute obstructive hydrocephalus due to a colloid cyst adjacent to the third ventricle is a rare condition, it is a potentially reversible neurologic cause of out-of-hospital cardiac arrest. However, positive outcomes depend on obtaining the diagnosis rapidly with neurologic imaging and advocating for neurosurgical intervention. This case supports the recommendation that emergency physicians should strongly consider post-cardiac arrest neurologic imaging when another cause is not immediately obvious.

Endoscopic third ventriculostomy (ETV) and ventriculoperitoneal shunt (VPS) are surgical methods for treating obstructive hydrocephalus. However, there is still disagreement regarding the most effective technique, in terms of both operative success and postoperative complications. Therefore, we performed a systematic review and meta-analysis to compare the efficacy and safety of these two methods in patients with obstructive hydrocephalus. We performed a systematic search of the PubMed, Scopus, and Cochrane Library databases. Randomized clinical trials (RCTs) comparing ETV and VPS in pediatric or adult patients with obstructive hydrocephalus were included. The outcomes included were operative success, postoperative cerebrospinal fluid leak, postoperative infection, postoperative or intraoperative bleeding, blockage rate, and mortality. The risk ratio (RR) was calculated with a 95% confidence interval (CI). Heterogeneity was evaluated with I 2 statistics. We used a fixed-effects model for outcomes with I 2  < 25% and DerSimonian and Laird random-effects model for other conditions. The Cochrane collaboration tool for assessing the risk of bias in randomized trials was used for risk-of-bias assessment. R, version 4.2.1, was used for statistical analyses. Of the 2,353 identified studies, 5 RCTs were included, involving 310 patients with obstructive hydrocephalus, of which 163 underwent ETV. There was a significant difference in favor of ETV for postoperative infection (risk ratio [RR]: 0.11; 95% confidence interval [CI]: 0.04-0.33; p  < 0.0001; I 2  = 0%) and blockage rate (RR: 0.15; 95% CI: 0.03-0.75; p  = 0.02; I 2  = 53%). Meanwhile, there was no significant difference between groups for the postoperative or intraoperative bleeding (RR: 0.44; 95% CI: 0.17-1.15; p  = 0.09; I 2  = 0%), postoperative cerebrospinal fluid leak (RR: 0.65; 95% CI: 0.22-1.92; p  = 0.44; I 2  = 18%), operative success (RR: 1.18; 95% CI: 0.77-1.82; p  = 0.44; I 2  = 84%), and mortality (RR: 0.19; 95% CI: 0.03-1.09; p  = 0.06; I 2  = 0%). Three RCTs had some concerns about the risk of bias and one RCT had a high risk of bias due to the process of randomization and selection of reported results. Thus, this meta-analysis of RCTs evaluating ETV compared with VPS demonstrated that although there is no superiority of ETV in terms of operative success, the incidence of complications was significantly higher in patients who underwent VPS. Our results suggest that the use of ETV provides greater benefits for the treatment of obstructive hydrocephalus. However, more RCTs are needed to corroborate the superiority of ETV.

BACKGROUND: We present a unique case of monozygotic female twins with virtually identical clinical and radiological presentations of supratentorial hydrocephalus and cystic formations from the suprasellar cistern.
CONCLUSIONS: Evaluating genetic predispositions and prenatal exposures is crucial for hydrocephalus in twins. Familial cases imply a genetic contribution to the development of these anomalies, including chromosomal abnormalities and specific variants linked to arachnoid cyst formation in various syndromes. Extensive genetic analyses found no pathogenic variants in the twins. Prenatal exposure to anti-epileptic medication was known during pregnancy and may be associated with fetal abnormalities, but not central nervous system (CNS) malformations, and was therefore not considered the cause of the condition in the twins. The twins presenting simultaneously with hydrocephalus caused by suprasellar cysts (SAC) underwent a two-step surgical management: initial ventriculoperitoneal shunt (VPS) placement followed by fenestration. Postoperative imaging showed cyst reduction, but a secondary VPS was necessary in both cases.
CONCLUSIONS: Genetic analysis is less likely to identify a monogenic etiology in non-syndromic cases of SACs, which are assumed to be multifactorial. There is no established evidence linking a teratogenic effect of anti-epileptic drugs to CNS malformations. Moreover, the surgical treatment of this complex condition constitutes a point of discussion.

BACKGROUND: Diffuse neonatal hemangiomatosis (DNH) is a rare disorder typically recognized at birth or during the neonatal period. DNH involves three or more organ systems, including the central nervous system (CNS). In these cases, serious complications such as hemorrhages and obstructive hydrocephalus can develop.
METHODS: We present a case of DNH with intracranial hypertension and CNS hemorrhagic lesions on the mesencephalic aqueduct, resulting in triventricular hydrocephalus, treated with endoscopic ventriculocisternostomy (ETV) and medical therapy.
CONCLUSIONS: DNH is a rare condition that can involve the CNS with serious complications. From a review of the literature, we highlighted only two cases of DNH with brain involvement treated surgically. We report the successful outcome of ETV, along with surgical considerations, imaging findings, and the complete resolution of cerebral and skin lesions following medical therapy.
CONCLUSIONS: Medical therapy is not standardized and must be individualized. In patients who develop severe neurological symptoms such as obstructive hydrocephalus, surgery may be considered to avoid neurological sequelae.