Eduardo Mendes Correa

Skull base meningoceles are extremely rare, most commonly resulting from congenital defects in sphenoid bone fusion. Inadequate embryonic fusion between the posterior sphenoid and the occipital bones may result in a transclival meningocele. Given the absence of a formal classification system for clival meningoceles and clear guidelines for the most appropriate endoscopic skull base surgical approach, we combined an anatomical study and a systematic review to characterize anatomical patterns, propose a preliminary classification, and discuss transoral and endonasal surgical corridors according to each clival subtype. In addition, we report the first known case of a primary clival meningocele successfully treated via a transoral endoscopic approach. The study was registered with PROSPERO (CRD42024575282) and received approval from the Ethics Committee (82878724.1.0000.5259). The systematic review followed PRISMA guidelines. PubMed/MEDLINE, Embase, and Cochrane were rigorously searched. Anatomical dissection of midsagittal skull base specimens was performed to assess surgical access to clival regions. Seventeen studies comprising 18 patients (mean age 30.7 years; 72.2% female) were included. Clival defects were classified as posterior transsphenoidal (n = 11), spheno-occipital (n = 1), and basioccipital (n = 6). The endoscopic endonasal approach appeared more appropriate for posterior transsphenoidal cases and the transoral route for basioccipital defects. Anatomical dissection studies confirmed that the endonasal corridor is more suitable for the upper third of the clivus and the transoral route for the lower third.

The role of intraoperative neurophysiological monitoring (IONM) in intradural extramedullary (IDEM) tumor surgery is uncertain. While IONM is standard in intramedullary and deformity procedures, its impact on neurological outcomes in IDEM resections has not been systematically evaluated. To assess whether IONM reduces early postoperative neurological morbidity in IDEM tumor surgery. We conducted a PROSPERO-registered systematic review and meta-analysis (CRD420251119538) in accordance with PRISMA 2020. Comparative studies of IDEM resections with versus without IONM were included. Outcomes were harmonized into a binary “new neurological deficit” at discharge. Risk of bias was assessed with ROBINS-I, and certainty of evidence with GRADE. Pooled odds ratios (ORs) were calculated using a random-effects model. Four retrospective cohorts comprising 602 patients (306 with IONM, 296 without) were analyzed. In absolute terms, early postoperative neurological deficits occurred in 19/306 patients (6.2%) in the IONM group versus 45/296 patients (15.2%) in the non-IONM group. Pooled analysis showed a significant reduction in early postoperative neurological deficits with IONM compared to no IONM group (OR 0.39, 95% CI 0.20–0.75; p = 0.005; I² = 22%), corresponding to an absolute risk reduction of 9.2% (NNT ≈ 11). Sensitivity analysis revealed dependence on certain large studies. Risk of bias was moderate-to-serious, and certainty of evidence was rated low. IONM use was associated with lower odds of early postoperative neurological deficits in IDEM tumor surgery, and the effect is based on low-certainty observational evidence. These findings are hypothesis-generating and support selective rather than universal use of IONM, particularly in higher-risk cases. Prospective multicenter studies with standardized outcomes, longer follow-up, and cost-effectiveness analyses are needed to define its optimal role.

Background: Porencephalic cysts are rare cerebrospinal fluid-filled cavities within the brain parenchyma, classified as either congenital or acquired (secondary to trauma, surgical interventions, ischemia, or infections). Clinical presentations vary depending on the cyst’s size, location, and associated mass effect, with diagnosis established through neuroimaging. This report describes a rare, life-threatening exacerbation of a chronic porencephalic cyst in an adult, progressing to hydrocephalus and acute intracranial hypertension (IH). Case Description: A 57-year-old female presented to an outpatient clinic with an 8-month history of gait disturbances, memory impairment, apathy–abulia, and wheelchair dependence. Eight years earlier, she had sustained a mild traumatic brain injury, during which a porencephalic cyst was incidentally detected on cranial computed tomography (CT) scan; however, she had not been followed up, and the finding was not disclosed during the current evaluation. A new cranial CT and magnetic resonance imaging revealed a large porencephalic cyst in the left frontal lobe with mass effect, bilateral foramen of Monro obstruction, and hydrocephalus. An elective endoscopic cyst-ventricle communication was planned. Two weeks later, the patient presented signs of acute IH, including severe headache, diplopia, and blurred vision. An emergent external ventricular drain (EVD) was placed into the cyst cavity, leading to rapid symptom relief. The EVD was subsequently replaced by a cyst-peritoneal shunt. One year later, the proximal catheter became exposed and required complete shunt removal. Since then, she has remained clinically stable and shunt free. Conclusion: This case represents a rare, adult-onset, life-threatening exacerbation of chronic porencephaly. It demonstrates the importance of long-term follow-up in patients with known porencephalic cysts, even if previously asymptomatic, and the efficacy of timely neurosurgical intervention and close radiological monitoring in preventing severe or potentially fatal complications.

Endolymphatic sac tumor (ELST) is a rare lesion. It may be sporadically or associated with Von Hippel-Lindau syndrome.

Isolated hypertelorism is a rare congenital condition caused by craniofacial malformations.

Temporal bone squamous cell carcinoma (TBSCC) is a very rare condition. The prognosis is dismal for advanced tumors. Due to its rarity, information in the literature is scarce. Here, we report a unique case of TBSCC with cerebellar invasion and hydrocephalus. A 46-year-old reported right-sided hearing loss and a painful right retroauricular mass for 4 months. Magnetic resonance imaging revealed a 8.7 × 7.6 × 6.4 cm mass invading the right temporal and occipital bones. After a biopsy and 3 surgical procedures over 6 months, the diagnosis of TBSCC was obtained. Due to invasion of the cerebellar tissue and obstructive hydrocephalus, a ventriculoperitoneal shunt was performed. The patient was referred for adjuvant radiotherapy. However, palliative care was initiated due to tumor progression. We report a case of advanced TBSCC with poor prognosis despite surgical treatment and radiotherapy. More data are necessary to provide new and better treatment to these patients.