Postoperative Cerebrospinal Fluid-Related Complications After Posterior Fossa and Posterolateral Skull Base Surgeries: Development of a Predictive Model and Clinical Risk Score.

BACKGROUND: Postoperative pseudomeningocele (PMC) and cerebrospinal fluid (CSF) leak are common complications following posterior fossa and posterolateral skull base surgeries. We sought to 1) determine the rate of CSF-related complications and 2) develop a perioperative model and risk score to identify the highest risk patients for these events. METHODS: We performed a retrospective cohort of 450 patients undergoing posterior fossa and posterolateral skull base procedures from 2016 to 2020. Logistic regressions were performed for predictor selection for 3 prespecified models: 1) a priori variables, 2) predictors selected by large effect sizes, and 3) predictors with P ≤ 0.100 on univariable analysis. A final model was created by elimination of nonsignificant predictors, and the integer-based postoperative CSF-related complications (POCC) clinical risk score was derived. Internal validation was done using 10-fold cross-validation and bootstrapping with uniform shrinkage. RESULTS: A total of 115 patients (25.6%) developed PMC and/or CSF leakage. Age >55 years (odds ratio [OR], 0.560; 95% confidence interval [CI], 0.328-0.954), body mass index >30 kg/m2 (OR, 1.88; 95% CI, 1.14-3.10), and postoperative CSF diversion (OR, 2.85; 95% CI, 1.64-5.00) were associated with CSF leak and PMC. Model 2 was the most predictive (cross-validated area under the receiver operating characteristic curve, 0.690). The final risk score was devised using age, body mass index class, dural repair technique, use of bone substitute, and duration of postoperative CSF diversion. The POCC score performed well (cross-validated area under the receiver operating characteristic curve, 0.761) and was highly specific (96.1%). CONCLUSIONS: We created the first generalizable and predictive risk score to identify patients at risk of CSF-related complications. The POCC score could improve surveillance, inform doctor-patient discussions regarding the risks of surgery, and assist in perioperative management.

Transpetrosal Approach to a Ruptured Distal Basilar Perforating Artery Aneurysm.

Basilar perforating artery aneurysms are rare and underreported vascular anomalies in the cerebrovascular literature. Various open and endovascular treatment approaches can be employed to treat these aneurysms based on several patient- and aneurysm-specific factors. Some authors have even advocated for conservative, nonoperative management. Here, we report a case of a ruptured distal basilar perforating artery aneurysm secured by an open transpetrosal approach. A 67-year-old male presented to our institution with a Hunt-Hess grade 2, modified Fisher grade 3 subarachnoid hemorrhage (SAH). Initial cerebral digital subtraction angiography (DSA) did not identify an intracranial aneurysm or other vascular lesions. However, the patient had a re-rupture event several days after presentation. DSA at this time revealed a posteriorly projecting distal basilar perforating artery aneurysm. Initial attempts with endovascular coil embolization were unsuccessful. Thus, an open transpetrosal approach was taken to gain access to the middle and distal basilar trunk to secure the aneurysm. This case underscores the unpredictability of basilar perforating artery aneurysms and the challenges encountered when considering active treatment. We demonstrate an open surgical approach with an intraoperative video for definitive management after failed attempted endovascular treatment.

Incidence and management of postoperative pseudomeningocele and cerebrospinal fluid leak after Chiari malformation type I decompression.

OBJECTIVE: The optimal surgical management of Chiari malformation type I (CM-I) remains controversial and heterogeneous. The authors sought to investigate patient-specific, technical, and perioperative features that may affect the incidence of CSF-related complications including pseudomeningocele and CSF leak at their institution. METHODS: The authors performed a single-center, retrospective review of all adult patients with CM-I who underwent posterior fossa decompression. Patient demographics, operative details, and perioperative factors were collected via electronic medical record review. The authors performed Fisher's exact test and independent Student t-tests for categorical and continuous variables, respectively. Univariate regression analysis was performed to determine odds ratios. A multivariable regression analysis was performed for those factors with p < 0.10 or large effect sizes (OR ≥ 2.0 or ≤ 0.50) by univariate analysis. The STROBE guidelines for observational studies were followed. RESULTS: A total of 59 adult patients were included. Most patients were female (78.0%), and the mean body mass index was 32.2 (± 9.0). Almost one-third (30.5%) of patients had a syrinx on preoperative imaging. All patients underwent expansile duraplasty, of which 47 (79.7%) were from autologous pericranium. Arachnoid opening for fourth ventricular inspection was performed in 26 (44.1%) cases. CSF-related complications were identified in 18 (30.5%) of cases. Thirteen (22.0%) patients required readmission and 11 (18.6%) required intervention such as wound revision (n = 5), wound revision with CSF diversion (n = 4), CSF diversion alone (n = 1), or blood patch (n = 1). Three (5.1%) patients required permanent CSF diversion. Male sex (OR 3.495), diabetes mellitus (OR 0.249), tobacco use (OR 2.53), body mass index more than 30 (OR 2.45), preoperative syrinx (OR 1.733), autologous duraplasty (OR 0.331), and postoperative steroids (OR 2.825) were included in the multivariable analysis. No factors achieved significance by univariate or multivariable analysis (all p > 0.05). CONCLUSIONS: The authors report a single-center, retrospective experience of posterior fossa decompression for 59 adults with CM-I. No perioperative or technical features were found to affect the CSF-related complication rate. More standardized practices within centers are necessary to better delineate the true risk factors and potential protective factors against CSF-related complications.

Management of Cerebral Herniation Secondary to Lead Encephalopathy: A Case Report.

Background: Adult lead encephalopathy is a rare but critical condition to recognize in modern healthcare settings. Few reports have described the medical and neurosurgical management of severe adult lead encephalopathy. Case Presentation: A 22 year old woman presented with severe headache, anemia, vomiting, 40-lb weight loss, and constipation. At the time of presentation, she had extensive colonic radiopaque material and a serum lead concentration of 87 mcg/dl (normal <10). She rapidly developed anisocoria requiring emergent ventriculostomy insertion. Following CSF diversion, ICP mitigation, and lead chelation, she considerably improved in <2 weeks. Conclusion: We report one of the few instances of successful surgical and medical management of adult lead encephalopathy. Dedicated neurocritical care and neurosurgical teams are necessary in conjunction with toxicology in order to manage the advanced sequalae of severe lead poisoning.

Depression and glioblastoma, complicated concomitant diseases: a systemic review of published literature.

Glioblastoma multiforme (GBM) is the most common primary brain cancer. Depression is a common co-morbidity of this condition. Despite this common interaction, relatively little research has been performed on the development of GBM-associated depression. We performed a literary search of the PubMed database for articles published relating to GBM and depression. A total of 85 articles were identified with 46 meeting inclusion criteria. Depression significantly impacts care, decreasing medication compliance, and patient survival. Diagnostically, because depression and GBM share intricate neuro-connectivity in a way that effect functionality, these diseases can be mistaken for alternative psychological or pathological disorders, complicating care. Therapeutically, anti-depressants have anti-tumor properties; yet, some have been shown to interfere with GBM treatment. One reason for this is that the pathophysiological development of depression and GBM share several pathways including altered regulation of the 5-HT receptor, norepinephrine, and 3':5'-cyclic monophosphate. Over time, depression can persist after GBM treatment, affecting patient quality of life. Together, depression and GBM are complicated concomitant diseases. Clinicians must be aware of their co-existence. Because of overlapping molecular pathways involved in both diseases, careful medication selection is imperative to avoid potential adverse interactions. Since GBMs are the most common primary brain cancer, physicians dealing with this disease should be prepared for the development of depression as a potential sequela of this condition, given the related pathophysiology and the known poor outcomes.

Long-term Seizure Disorder Caused by a Dermoid Cyst with Catastrophic Developments.

Glioblastoma multiforme (GBM) is a World Health Organization (WHO) grade IV primary malignant astrocytoma. Aneurysms are devastating intracranial neurovascular pathologies. Intracranial dermoid cysts are common, benign lesions which can be clinically silent or associated with seizure disorder. We describe physically adjacent diagnoses of dermoid cyst, intracranial aneurysm, and GBM in a single patient. Records were collected and reviewed to compile the final clinical picture. A 72-year-old male with a long history of seizure disorder, presented with new focal, unilateral neurological deficits. Radiographic evaluation including computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a dermoid cyst with an underlying developing GBM, which also, by happenstance, contained an aneurysm. During open surgical resection, multiple macroscopically distinct tissue types were noted. Histological analysis of tissue from each lesion confirmed the diagnoses including dermoid cyst, GBM, and aneurysm. Pathological analysis revealed the presence of extensive inflammatory cells throughout. Subsequent staining identified CD68 positive cells indicating a probable chronic inflammatory state. Chronic inflammation resulting from the presence of a long term dermoid cyst and ongoing seizures may have led to dystrophic changes in adjacent vasculature and approximating glial tissues, inducing the formation of an aneurysm and a secondary GBM. Therefore, while benign in nature, dermoid cysts can be related to seizure disorder and may cause chronic inflammation in surrounding brain tissue.

A Reanalysis of the RIVUR Trial Using a Risk Classification System.

PURPOSE: The RIVUR (Randomized Intervention for Children with Vesicoureteral Reflux) trial showed a 50% decrease in the risk of urinary tract infection recurrence in children with reflux receiving continuous antibiotic prophylaxis. We reanalyzed the RIVUR data with the purpose of using a risk classification system to identify children who are more likely to benefit from continuous antibiotic prophylaxis. MATERIALS AND METHODS: Data from 607 children enrolled in the RIVUR trial were obtained from the National Institute of Diabetes and Digestive and Kidney Diseases Central Repository and analyzed. We stratified these children into low and high risk categories. The proportion of children and risk of urinary tract infection recurrence in the stratified treatment groups were compared. RESULTS: Of the children 385 (63.9%) were stratified into the low risk and 217 (36.1%) into the high risk category. The proportions of children with urinary tract infection recurrence were not significantly different in the low risk category between the placebo and continuous antibiotic prophylaxis groups (p = 0.151), while urinary tract infection recurrence was significantly higher in the placebo group (31.5% vs 11.4%, p = 0.001) for high risk children. Furthermore, high risk children on placebo had a 3.7-fold increased risk of urinary tract infection recurrence during 2 years of followup compared to those on continuous antibiotic prophylaxis. CONCLUSIONS: Although the RIVUR trial concluded that children with vesicoureteral reflux benefit from continuous antibiotic prophylaxis, our reanalysis of the data demonstrates that high risk children benefit more, with a number needed to treat of 5 compared to 18 in low risk children. The clinical implications of these findings suggest a need to refine current indications for continuous antibiotic prophylaxis in children with reflux, supporting a shift toward a "selective" risk based approach for management.

Streptococcus Mutans: A Potential Risk Factor in Recurrent Hemorrhagic Stroke.

Stroke is the fifth leading cause of death and is responsible for approximately nine percent of all deaths worldwide. Cases of Streptococcus mutans (S. mutans)-induced intracerebral hemorrhage as a result of bloodstream infections have seldom been reported. New reports show that bacteria with specific collagen binding proteins (CBPs), such as the Cnm type produced by S. mutans, may inhibit platelet aggregation and cause bleeding. In this article, we report on a 62-year-old man with a recent history of left frontal intracerebral hemorrhage (ICH) who presented to the emergency department after a fall due to suspected seizure while in rehabilitation. Computed tomography (CT) scan of the brain showed a right cerebellar hemorrhage with surrounding edema and mass effect on the fourth ventricle. A suboccipital craniotomy to evacuate the cerebellar ICH was completed without complication. Radiologic and angiographic assessments regarding the etiology of this patient's stroke did not reveal any evidence of vascular pathology or mycotic aneurysms to explain his recurrent intracranial hemorrhages. Through persistent patient and family interviews, it came to light that a few weeks prior to the patient's first ICH, he was diagnosed with a bloodstream infection by S. mutans. Bacteremia is known to be associated with embolic stroke, but only recently has it been shown that bacteremia can also be implicated in hemorrhagic stroke. S. mutans of the k serotype have specific CBPs that are attracted to exposed collagen in previously damaged small vessel walls. These bacterial proteins can interrupt the blood clotting cascade through the prevention of platelet aggregation, increasing the risk of intracerebral hemorrhage.

The circle of Willis predicts the antihypertensive effects of carotid artery stenting.

OBJECTIVE Carotid artery stenting (CAS) has antihypertensive effects, but the durability and degree of this response remain variable. The authors propose that this clinical variability is a function of the presence or absence of a complete circle of Willis (COW). Incomplete COWs perfuse through a higher-resistance pial collateral pathway, and therefore patients may require a higher mean arterial pressure (MAP). Carotid artery revascularization in these patients would reduce the end-organ collateral demand that has been hypothesized to drive the MAP response. METHODS Using a retrospective, nonrandomized within-subject case-control design, the authors compared the postoperative effects of CAS in patients with and without a complete COW by using changes in MAP and antihypertensive medication as end points. They recorded MAP and antihypertensive medications 3 months prior to surgery, preoperatively, immediately postoperatively, and at the 3-month follow-up. RESULTS Data were collected from 64 consecutive patients undergoing CAS. Patients without a complete COW (25%) were more likely to demonstrate a decrease in BP response to stenting (i.e., a drop in MAP of 10 mm Hg and/or a reduction or cessation of BP medications at 3 months postoperatively). Of the patients in the incomplete COW cohort, 75% had this outcome, whereas of those in the complete COW cohort, only 41% had it (p < 0.041). These findings remained statistically significant in a logistic regression analysis for possible confounders (p < 0.024). A receiver operating curve analysis of preoperative data indicated that a MAP > 96.3 mm Hg was 55.5% sensitive and 57.4% specific for predicting a complete COW and that patients with a MAP > 96.3 mm Hg were more likely to demonstrate a good MAP decrease following CAS (p < 0.0092). CONCLUSIONS CAS is associated with a significant decrease in MAP and/or a reduction/cessation in BP medications in patients in whom a complete COW is absent.

PPARγ agonist-induced fluid retention depends on αENaC expression in connecting tubules.

BACKGROUND/AIMS: Thiazolidinediones (TZDs, like rosiglitazone (RGZ)) are peroxisome proliferator-activated receptor γ (PPARγ) agonists used to treat type 2 diabetes. Clinical limitations include TZD-induced fluid retention and body weight (BW) increase, which are inhibited by amiloride, an epithelial-sodium channel (ENaC) blocker. RGZ-induced fluid retention is maintained in mice with αENaC knockdown in the collecting duct (CD). Since ENaC in the connecting tubule (CNT) rather than in CD appears to be critical for normal NaCl retention, we aimed to further explore the role of ENaC in CNT in RGZ-induced fluid retention. METHODS: Mice with conditional inactivation of αENaC in both CNT and CD were used (αENaC lox/lox AQP2-Cre; 'αENaC-CNT/CD-KO') and compared with littermate controls (αENaC lox/lox mice; 'WT'). BW was monitored and total body water (TBW) and extracellular fluid volume (ECF) were determined by bioelectrical impedance spectroscopy (BIS) before and after RGZ (320 mg/kg diet for 10 days). RESULTS: On regular NaCl diet, αENaC-CNT/CD-KO had normal BW, TBW, ECF, hematocrit, and plasma Na(+), K(+), and creatinine, associated with an increase in plasma aldosterone compared with WT. Challenging αENaC-CNT/CD-KO with a low NaCl diet unmasked impaired NaCl and K homeostasis, consistent with effective knockdown of αENaC. In WT, RGZ increased BW (+6.1%), TBW (+8.4%) and ECF (+10%), consistent with fluid retention. These changes were significantly attenuated in αENaC-CNT/CD-KO (+3.4, 1.3, and 4.3%). CONCLUSION: Together with the previous studies, the current results are consistent with a role of αENaC in CNT in RGZ-induced fluid retention, which dovetails with the physiological relevance of ENaC in this segment.