Journal of neurosurgery. Case lessons最新文献

Background: The association of idiopathic intracranial hypertension (IIH) with spontaneous skull base CSF leaks is well known; however, its role in spinal CSF leaks is poorly established. CSF-venous fistula (CVFs) are a recognized subtype of spinal CSF leaks, but they rarely recur after successful treatment. Brainstem sagging is a known consequence of spontaneous intracranial hypotension with variable clinical sequelae. Brainstem sagging has not previously been demonstrated to cause obstructive hydrocephalus.

Observations: The authors describe the case of a female in her early 5th decade with presumed IIH-induced recurrent spinal CVFs. They detail the recurrent nature of her CVFs despite successful transvenous embolization, the advanced imaging techniques required for diagnosis, and the consequences of untreated intracranial hypotension, including bulbar dysfunction and obstructive hydrocephalus requiring external ventricular drainage. The placement of a ventriculoperitoneal shunt to prevent further spinal CVF recurrence is also described.

Lessons: This illustrative case highlights the complexity of treatment in recurrent spinal CVFs and intracranial hypotension. The authors detail the extreme consequences of untreated intracranial hypotension, including obstructive hydrocephalus and progressive bulbar dysfunction. In this context, the necessity of external ventricular drainage in order to equalize transtentorial pressure differentials and restore consciousness is demonstrated. https://thejns.org/doi/10.3171/CASE25680.

Background: Glioblastoma (GB) typically recurs locally and maintains a glial histopathological phenotype. Sarcomatoid transformation is rare, and distal extra-axial recurrence with bone and soft tissue involvement is exceptionally uncommon. Molecular features of such sarcomatoid transformations remain poorly described.

Observations: The authors present the case of a 53-year-old man with a history of right temporal GB (IDH-wildtype, MGMT-unmethylated) treated with maximal safe resection and chemoradiotherapy. Eleven months postoperatively, surveillance MRI demonstrated local enhancement with a new left parasagittal extra-axial lesion with bony and subgaleal extension. Debulking and resection revealed a high-grade sarcomatoid tumor with focal glial immunophenotype, mimicking a secondary gliosarcoma but with near-complete predominance of the sarcomatous component. Molecular analysis demonstrated preservation of TERT, PIK3CA, and PTEN variants identified in the original GB, with acquisition of a TP53 mutation.

Lessons: This case illustrates a rare pattern of GB progression, characterized by distal extra-axial recurrence with sarcomatoid transformation. The shared driver TERT, PIK3CA, and PTEN mutations in the original right temporal and subsequent left extra-axial lesion support clonal evolution, while the newly acquired TP53 alteration may underlie histological shift. Clinicians should consider histological transformation when evaluating atypical or extracranial recurrences, as molecular continuity with the primary tumor can guide interpretation of tumor biology and recurrence patterns. https://thejns.org/doi/10.3171/CASE25714.

Background: Extracranial metastasis from meningiomas is rare, with pulmonary involvement being the most frequent metastatic site. The authors present this case to highlight the diagnostic and management challenges associated with atypical meningiomas that metastasize outside the CNS, and to emphasize the importance of long-term surveillance even in patients with radiologically stable disease.

Observations: A 33-year-old male was initially diagnosed with an intracranial atypical meningioma (WHO grade II, 2007 classification) characterized by increased cellularity, mild nuclear atypia, and a mitotic index ≥ 4 mitoses per 10 high-power fields, without brain invasion. Seven years later, he developed multiple pulmonary metastases confirmed by histopathological analysis. Given the absence of symptoms and minimal progression of pulmonary lesions over a 7-year follow-up period, the patient was managed conservatively with structured surveillance, including regular cranial MRI and chest CT imaging.

Lessons: This case demonstrates that long-term stability of pulmonary metastases from atypical meningioma is possible under conservative management. Structured surveillance with periodic cranial and thoracic imaging may be appropriate for asymptomatic patients, while reserving surgical or radiotherapy options for those with progressive or symptomatic disease. https://thejns.org/doi/10.3171/CASE25761.

Background: Approximately 35% of pituitary adenomas that require surgical intervention are invasive, often extending into the cavernous sinus (CS) via dural wall defects. Given the connections between the CS and multiple valveless venous plexuses in the orbit, face, and clivus, hematological venous spread is plausible, but the pathway by which these tumors locally invade remains uncertain.

Observations: A 26-year-old man with right eye proptosis who presented for trauma was incidentally found to have an extensive pituitary mass. The lesion demonstrated invasion into both CSs, the right orbit, the bilateral retroclival space, and the right jugular foramen, with radiographic extension into a dilated right superior ophthalmic vein. Laboratory workup revealed a markedly elevated prolactin level of 18,178 ng/mL (normal: 2.10-17.70 ng/mL), consistent with a giant prolactinoma. He was treated effectively with cabergoline and without surgery.

Lessons: To the authors' knowledge, this is the first documented case illustrating extensive venous-mediated spread of a pituitary adenoma through valveless venous networks involving the CS, orbital, and clival regions, and it provides a plausible mechanism for the enhanced invasive nature of prolactin-secreting tumors. This case underscores the need for thorough imaging and endocrine evaluation before considering the surgical management of suspected invasive pituitary lesions. https://thejns.org/doi/10.3171/CASE25891.

Background: Arachnoid web (AW) is a rare entity characterized by a thickened band of arachnoid membrane on the dorsal surface of the spinal cord, often producing compressive myelopathy. The diagnosis is sometimes challenging, as imaging findings may be subtle.

Observations: The authors report the case of a 29-year-old man who developed paraparesis with bladder and rectal dysfunction following a minor traffic accident. Imaging showed no fractures or intramedullary signal changes, with only subtle spinal cord anterior deviation at T7-8. Surgical exploration revealed a thickened arachnoid band compressing and tethering the spinal cord. Resection of the AW restored cord pulsation, and motor function improved postoperatively. Histopathology confirmed arachnoid tissue with collagen fibers, consistent with AW.

Lessons: Even with subtle imaging findings, AW should be suspected in trauma-related myelopathy, and timely surgical intervention can provide recovery. https://thejns.org/doi/10.3171/CASE25734.

Background: Ulnar neuropathy at Guyon's canal is rare, but when it occurs, it is frequently due to underlying masses, including extraneural and intraneural ganglion cysts, as well as adventitial cysts. The pathogenesis of these cysts, especially at a rare site, remains controversial. The articular theory, which is gaining popularity, posits that a joint connection via a nerve (or vascular) branch to a neighboring joint represents the pathway for their formation and propagation.

Observations: A recently published case of a patient with an ulnar intraneural ganglion at the wrist with a series of postoperative cystic recurrences was reevaluated, as it challenged the articular theory. No discrete articular branch had been identified on imaging or at surgery. Serial MR images were reinterpreted, which revealed that the original intraneural cyst was treated; new sequential cysts-an adventitial cyst and then a soft tissue ganglion-developed, all arising from the same wrist joint.

Lessons: This case strengthens the principles of the articular theory for intraneural ganglion, adventitial, and soft tissue ganglion cysts. A small wrist connection from the ulnar intraneural ganglion was unrecognized and untreated. Scarring disrupted the original nerve pathway and pressure dynamics. New cysts developed through neighboring joint capsular rents along different pathways into other "compartments" (vessel or soft tissues). https://thejns.org/doi/10.3171/CASE25618.

Background: Skull metastases from hepatocellular carcinoma (HCC) are rare and may cause significant neurological deficits. Conventional cranioplasty using titanium mesh or polyetheretherketone can result in imaging artifacts and implant-related complications. Cryotherapy provides a potential means to sterilize tumor-infiltrated autologous bone for reuse in reconstruction.

Observations: A man in his 50s with hepatitis B virus-associated HCC presented with cognitive and speech disturbances. Imaging revealed a 5-cm left temporo-parieto-occipital skull lesion with intracranial extension. The tumor-infiltrated bone flap was excised, treated with liquid nitrogen at -60°C to -80°C for 20 minutes, and reimplanted after tumor resection. Histopathology confirmed metastatic HCC involving the skull and brain. Three-month follow-up MRI and CT demonstrated no recurrence, excellent bone flap integration, and no imaging artifacts. The patient's neurological symptoms were resolved postoperatively.

Lessons: Cryosurgical cranioplasty using autologous bone offers a biologically compatible, imaging-friendly, and oncologically safe alternative to synthetic implants for metastatic skull lesions, enabling effective reconstruction and reliable postoperative surveillance. https://thejns.org/doi/10.3171/CASE25852.

Background: Posterior fossa penetrating traumatic brain injury (pTBI) in military combat is rare but carries high neurovascular risk.

Observations: A 51-year-old male sustained a mine explosion injury in Ukraine, in which a 4 × 1.5-cm metal fragment penetrated through the skull base into the posterior cranial fossa. The fragment was adjacent to the vertebral artery, sigmoid sinus, lower cranial nerves, and occipital condyle. Digital subtraction angiography was completed on arrival, which showed a patent right vertebral artery, occluded transverse-sigmoid sinus, and partial internal jugular vein occlusion. The patient underwent a right retrosigmoid craniotomy for foreign body removal and debridement. CSF release from the cerebellomedullary cisterns facilitated visualization while reducing retraction injury risk. The fragment was removed atraumatically and a vascularized pericranial graft was used for closure.

Lessons: Military posterior fossa pTBI presents unique challenges related to blast mechanisms. Effective management requires early angiography for suspicion of vascular injury and meticulous microsurgical technique, even in resource-constrained environments where a one-stage, comprehensive approach to treatment may be valuable. https://thejns.org/doi/10.3171/CASE25563.

Background: Symptomatic cavernous portion internal carotid artery (ICA) aneurysms require prompt treatment due to their neurological impact. The authors report a case successfully treated with ICA ligation and superficial temporal artery-middle cerebral artery (STA-MCA) bypass, guided by intraoperative cortical/systemic pressure and MCA pressure ratios before and after bypass release to prevent infarction, achieving complete aneurysm obliteration without deficits.

Observations: An 84-year-old woman presented with sudden-onset headache and right external ophthalmoplegia. Imaging studies revealed a 24-mm aneurysm in the right ICA within the cavernous sinus and a 13-mm aneurysm in the left ICA cavernous segment. Severe common carotid artery atherosclerosis made endovascular treatment challenging. Preoperative cervical CT also revealed a 45-mm × 33-mm benign right thyroid mass, increasing the risk of cervical manipulation. ICA ligation with high-flow bypass was considered high-risk; therefore, ICA ligation with STA-MCA bypass was performed. Intraoperative cortical/systemic pressure and MCA pressure ratios after ligation and two STA-MCA anastomoses were 0.77 and 0.87, respectively, indicating low ischemic risk. Postoperatively, no new deficits occurred, and ophthalmoplegia improved.

Lessons: Intraoperative measurement of cortical/systemic and MCA pressure ratios, combined with thorough preoperative evaluation, can help assess ischemic risk and improve surgical safety. https://thejns.org/doi/10.3171/CASE25630.

Background: Trigeminal neuralgia (TN) is typically caused by vascular compression, often at the root entry zone (REZ) of the trigeminal nerve. While most cases involve extraneural compression, rare instances of intraneural transfixion exist, posing unique surgical challenges.

Observations: The authors report the case of a 77-year-old male with TN caused by intraneural vascular compression type 2, where a loop of the superior cerebellar artery (SCA) transfixed the portio major of the trigeminal nerve. MRI and intraoperative findings confirmed the SCA coursing through the nerve. He underwent microvascular decompression, during which internal neurolysis and Teflon pledget placement near the REZ were performed. Complete pain relief was achieved immediately postoperatively and sustained at the 7-month follow-up, with no associated postoperative numbness. A review of the literature reveals common themes of surgical intervention, including longitudinal dissection of the nerve, mobilization of penetrating artery outside of the REZ, and Teflon insertion.

Lessons: For type 1 penetrations, the authors suggest separating the motor and sensory roots, then mobilizing the motor root and artery. For type 2, they recommend either internal neurolysis with distal movement of the artery or horizontal transection to free the artery from the nerve. Patient-centered planning that balances risk of sensory loss against symptom recurrence is essential. https://thejns.org/doi/10.3171/CASE25403.