Surgical neurology international最新文献

Background: Meningiomas are the most common intracranial tumor. Ionizing radiation has been implicated in the pathogenesis of radiation-induced meningiomas (RIM). Compared to spontaneous meningiomas, RIM are a clinically aggressive entity and are more likely to develop clinical and radiologic progression.

Methods: Systematic searches of Medline, Embase, and Cochrane Central Register of Controlled Trials were performed. Pooled data were used to calculate rates of survival, tumor control, and adverse events.

Results: Thirty studies met the final inclusion criterion within this meta-analysis. In total, these studies reported on 927 RIMs in 825 patients. Patients were grouped by whether they received cranial radiotherapy ([CRT]; n = 555 patients) or scalp radiotherapy for tinea capitis ([TC]; n = 270 patients). The median dose prescribed to the CRT and TC groups was ~30 Gy and 1.5 Gy, respectively. The radiation interval to meningioma development between CRT and TC groups were 21.54 and 40.49 years, respectively (P < 0.0001). Twenty-six studies reported a 1-year overall survival rate, with a pooled survival rate of 95.46% (95% confidence interval [CI]: 92.31-97.82%, I2 = 51.9%, P = 0.0012). One-year progression-free survival was reported by 9 studies, with a pooled rate of 99.71% (95% CI: 97.62-100.00%, I² = 3.3%, P = 0.4076). From two studies, the pooled 1-year local recurrence rate was 16.54% (95% CI: 0.00-34.06%, I² = 0.0%, P = 0.5918), while the overall pooled local recurrence rate was 27.35% (95% CI: 17.98-36.73%, I² = 74.5%, P < 0.0001) from 23 studies.

Conclusion: High- and low-dose cranial radiation therapy can differentially influence the latency and grade of RIM, with higher dose CRT associated with earlier onset and more atypical tumors RIM screening may be warranted in individuals with an early exposure to cranial radiation given the increased risk of developing secondary neoplasms. These findings support structured long-term magnetic resonance imaging surveillance for survivors of childhood cranial irradiation, with risk adapted follow-up protocols to enable earlier detection and management.

Background: Cryptococcus neoformans is an opportunistic fungus with marked neurotropism, classically affecting immunocompromised patients, even though occasionally reported in immunocompetent hosts. Skull involvement is exceptionally rare and may radiologically mimic malignant tumors, causing diagnostic delays.

Case description: A 34-year-old immunocompetent male presented with a painless, progressive left parieto-occipital scalp swelling over 3 weeks. Imaging revealed a well-defined, dumbbell-shaped cystic mass beneath the scalp, causing lytic skull erosion and limited intracranial extension, suggestive of atypical meningioma or skull-based sarcoma. Surgical excision was performed, showing dural infiltration without leptomeningeal spread. Histopathology, the mass revealed granulomatous inflammation with abundant CD68+ histiocytes, mixed B- and T-cell infiltrates, and encapsulated budding yeasts (5-10 μm) within enlarged perivascular spaces. Gomori Methenamine Silver and periodic acid-Schiff staining confirmed fungal elements; culture identified Cryptococcus species.

Conclusion: Skull cryptococcosis in immunocompetent patients is rare but can occasionally present as an inflammatory pseudotumor with osteomyelitis and extracranial extension. Its imaging resemblance to aggressive neoplasms underscores the importance of including fungal etiologies in the differential diagnosis of destructive skull lesions, regardless of the immune status.

Background: Posterior cervical fixation with lateral mass screws (LMSs) and cervical pedicle screws (CPS) is well established, but free-hand and fluoroscopy-guided techniques remain limited by accuracy and safety concerns. Intraoperative O-arm navigation provides real-time three-dimensional (3D) imaging and may improve precision while reducing complications. This study evaluates screw accuracy, safety, operative parameters, and functional outcomes using O-arm-guided posterior cervical fixation.

Methods: This ambispective observational cohort analyzed 147 screws placed under O-arm-based 3D navigation. Primary outcome was screw accuracy graded on intraoperative O-arm scans; secondary outcomes included breach rates, complications, operative metrics, blood loss, radiation dose, and functional scores (Visual Analog Scale [VAS], modified Japanese Orthopaedic Association [mJOA], Nurick, American Spinal Injury Association) assessed over 1 year.

Results: Overall screw accuracy was 99.3%, with 146 screws fully contained and one C2 CPS showing a high-grade breach (0.7%) without neurological deficit. No wound infections, hardware failures, or reoperations were recorded. Functional outcomes improved significantly: mean VAS decreased from 5.5 to 1.8, mJOA increased from 12.6 to 14.3, and Nurick grade improved from 3.1 to 2.4 at 12 months (all P < 0.01). Average operative time was 236 min, blood loss 350 mL, and mean radiation dose 1145 mGy•cm.

Conclusion: In this observational cohort of 147 screws for posterior cervical fixation with O-arm navigation, we achieved a screw placement accuracy of 99.3% with only one high-grade breach and no neurological deficits or reoperations.

Background: Epilepsy surgery is a well-established therapeutic option for patients with refractory focal epilepsy. Comprehensive clinical evaluation should encompass documentation of seizure semiology, high spatial resolution magnetic resonance imaging (MRI) sequences, prolonged video electroencephalography, and detailed neuropsychological assessment. Resective surgery remains the cornerstone for medically refractory focal-onset epilepsy. However, even after exhaustive investigation, subtle parenchymal changes on imaging can delay surgical resection, exacerbating the epilepsy burden on quality of life.

Case description: A 30-year-old male patient with a long-standing history of seizures was referred to an epilepsy center. The seizures were stereotypical and highly frequent, with unremarkable neurological findings. Multiple trials of anti-seizure medications failed to control the epileptic events. The presurgical evaluation aimed to identify the precise brain regions involved in the primary organization of seizures and to map the eloquent cortex. The extent of epileptic zone resection significantly influences surgical outcomes. Preoperative MRI revealed subtle findings suggestive of a lesion at the bottom of the inferior frontal sulcus, immediately anterior to the precentral sulcus. The patient underwent resection, guided by neuronavigation and intraoperative electrocorticography. Three-dimensional cortical reconstruction facilitated the intraoperative identification of landmarks and electrocorticography-guided resection of pathological brain tissue. Histopathological evaluation revealed neuronal depopulation and irreversible chronic injuries in the remaining neurons. The patient was discharged without neurological deficits or seizures.

Conclusion: In the literature, no specific lesions have been identified or characterized by microscopic inspection in up to 7.7% of cases. Asleep motor mapping identifies eloquent zones and mitigates functional impairment post-resection; direct electrical stimulation remains the gold standard technique for cortical mapping.

Background: Dialysis disequilibrium syndrome (DDS) is a rare but serious neurologic complication of hemodialysis caused by rapid osmotic shifts leading to cerebral edema. Although well recognized in nephrology, DDS is underappreciated in neurosurgical practice, where it often presents only after significant intracranial hypertension has developed. As dialysis use expands, early neurosurgical awareness is increasingly important.

Methods: This narrative review synthesizes current evidence on DDS pathophysiology, clinical features, diagnostic considerations, and management, with a specific focus on neurosurgical implications. Data from case reports, pooled analyses, and neurocritical care studies were examined to characterize intracranial pressure (ICP) changes associated with renal replacement therapy and to identify points for multidisciplinary intervention.

Results: DDS most frequently occurs during early or rapid hemodialysis in patients with markedly elevated urea levels. A pooled analysis shows ICP elevation in up to 73% of neurosurgical patients receiving intermittent hemodialysis versus 38% treated with continuous modalities. Despite these risks, standardized neurosurgical protocols for prevention or monitoring remain lacking. Evidence supports gradual urea clearance, early use of continuous therapies, and timely hyperosmolar treatment when cerebral edema develops. However, delayed recognition and limited cross-disciplinary coordination continue to hinder effective management.

Conclusion: DDS is a preventable neurocritical complication that requires stronger integration into neurosurgical practice. Improved interdisciplinary communication, structured monitoring strategies, and incorporation of DDS into neurocritical care training could support earlier recognition and safer dialysis initiation. Reframing DDS as a shared neurosurgical-nephrology responsibility is essential to moving from reactive treatment toward prevention and improving neurologic outcomes.

Background: Few studies demonstrated the efficacy of mechanical thrombectomy (MT) for the branches of the posterior circulation, such as the posterior inferior cerebellar artery (PICA). Here, we describe a patient who underwent MT for acute PICA occlusion and achieved a favorable outcome.

Case description: A 68-year-old man presented with dysarthria on waking, followed by movement difficulty. On examination, he had dysarthria, right-sided ataxia, decreased pain sensation on the left side below the neck, and no significant motor paralysis. The National Institutes of Health stroke scale score was 2. The electrocardiogram revealed atrial fibrillation. Diffusion-weighted imaging revealed right lateral medullary infarction. Magnetic resonance angiography revealed obstruction of the right proximal PICA, and fluid-attenuated inversion recovery imaging revealed hyperintensity in the PICA vermian branch of the fourth ventricle, suggesting thrombus. Emergency MT was performed, primarily using aspiration, resulting in partial reestablishment of the blood flow in the occluded vessel. Marked improvement in dysarthria was observed immediately after the procedure. Follow-up magnetic resonance image revealed no new ischemic changes. He experienced mild ataxia and sensory impairment and was transferred to a rehabilitation hospital on postoperative day 17 with a modified Rankin scale score of 2, which had improved to 1 on postoperative day 90.

Conclusion: Accurate diagnostic imaging and an appropriate endovascular treatment technique led to good recovery in the present case. Even in patients with incomplete reperfusion, restoring blood flow to the perforating branches supplying the brainstem can aid in preventing brainstem infarction.

Background: Arachnoid cysts and pilocytic astrocytomas (PAs) are pathologically distinct lesions. Arachnoid cysts are essentially cerebrospinal fluid (CSF)-filled collections lined by the arachnoid membrane, mostly congenital but sometimes developing later in life. In contrast, PAs are low-grade, solid-cum-cystic brain tumors arising from astrocytes that mainly affect children and young adults. Fourth ventricular PAs are exceptionally rare, with approximately 56 cases reported in the literature since the early 1990s.

Case description: We report a case of a 20-year-old female who presented with progressive headache, nausea, and gait imbalance. Magnetic resonance imaging (MRI) revealed a nonenhancing cystic lesion in the fourth ventricle, initially suspected to be an arachnoid cyst due to the absence of mural nodules or enhancing solid components. Given her symptomatic presentation, she underwent a midline suboccipital craniotomy with cyst fenestration. Intraoperatively, the appearance of the cyst did not resemble an arachnoid cyst; hence, the cyst wall was sent for histopathological evaluation, which confirmed the diagnosis of PA. Postoperatively, the patient experienced significant improvement in her symptoms, and her neurological examination normalized. Follow-up MRI at 1 year demonstrated no evidence of progression.

Conclusion: This case emphasizes the diagnostic difficulty of distinguishing cystic, nonenhancing PAs from arachnoid cysts on imaging alone, particularly in the fourth ventricle of adults. Our findings highlight the critical role of surgical exploration both for symptom relief and for obtaining tissue to establish a definitive diagnosis, as well as the importance of long-term radiological surveillance due to the limited resection achievable in this anatomically constrained region.

Background: Aplasia cutis congenita (ACC) is a rare congenital condition marked by the absence of skin layers and sometimes underlying structures. Its etiology is unclear, with up to 70% of cases involving the scalp. We report the first document case of ACC in Ghana.

Case description: A 1-day-old female, born through spontaneous vaginal delivery after an uneventful pregnancy, was referred for management of a scalp defect noted at birth. Examination revealed an 8 × 5.5 cm central scalp defect with absent cranial vault, partial fronto-parietal bone loss, dural defect, exposed arachnoid membranes, and visible superior sagittal sinus. Other physical findings were normal. Brain magnetic resonance imaging (MRI), whole-body MRI, and echocardiography were unremarkable. A brain computed tomography confirmed a skull defect. The patient underwent a duraplasty using bovine pericardium and received serial wound dressings with epithelial growth factors. The defect reduced to 4.5 × 3.6 cm post-surgery and continues to improve pending potential cranioplasty at 2 years. ACC is primarily diagnosed clinically, and this patient was diagnosed with type 1 ACC. Management depends on subtype, location, defect size, and infection risk. In this case, surgery was employed due to the size of defect and the risk it posed. Prognosis is generally favorable, but limited resources may delay and increase complications in low-income settings.

Conclusion: ACC with skull and dural involvement poses serious risks to infant survival in resource-limited settings, where systemic challenges are pervasive. This case highlights the importance of care that is locally adapted, affordable, and delivered through strong multidisciplinary collaboration.

Background: Primary meningeal melanoma is an exceedingly rare malignant neoplasm arising from leptomeningeal melanocytes, accounting for only 0.06-0.1% of all central nervous system tumors. These melanocytes, derived from neural crest cells, typically localize within the ventral leptomeninges of the spinal cord and brainstem. Lesions most often occur in the cervical or thoracic spine and may mimic meningioma, schwannoma, or metastasis. Due to its rarity and nonspecific imaging features, diagnosis relies on histopathologic and molecular confirmation following surgical resection. Complete excision with adjuvant radiation remains the mainstay of treatment, though long-term outcomes are poorly defined due to limited reports.

Case description: We present a 61-year-old woman with a multi-segmental thoracic lesion spanning T8-T12 causing progressive genital and low-back pain, paraparesis, and sensory deficits. Magnetic resonance imaging revealed a contrast-enhancing intradural lesion with ventral extramedullary and intramedullary components. The patient underwent T7-T12 laminectomies for microsurgical resection with continuous neuromonitoring. Following dural opening, the tumor was identified in the ventrolateral extramedullary space with focal invasion into the spinal cord. Resection of the extramedullary component of the tumor was first undertaken until the tumor coursed into the intramedullary compartment. Sharp dissection and meticulous pial entry allowed circumferential mobilization and safe removal of the intramedullary portion while preserving the spinal vasculature. A gross total resection was achieved. The patient had a transient exacerbation of her right lower extremity weakness, which improved back to baseline within a few weeks from surgery. Histopathology revealed a densely cellular melanocytic tumor with focal necrosis and low proliferative index. Genetic testing identified a guanine nucleotide binding protein, alpha q (GNAQ) missense variant, confirming primary meningeal melanoma. With no systemic disease, adjuvant fractionated radiation was planned. The patient's recovery was stable, and she was discharged to rehabilitation on postoperative day 9.

Conclusion: This case highlights the surgical nuances and diagnostic considerations involved in treating rare mixed intramedullary-extramedullary meningeal melanomas of the thoracic spine.