Primary epidural extraosseous Ewing sarcoma (EES) is a rare form of spinal Ewing sarcoma with soft tissue invasion of the spinal canal and neural foramen, without involvement of the bony spinal column. The authors report the case of a 19-year-old male presenting to the hospital with a 1-month history of left leg dysesthesias and neuropathic pain, followed by acute left leg weakness evolving over 1-2 weeks. Imaging revealed an epidural lesion at L2 with extension into the left L2-3 neural foramen. The patient underwent urgent surgery given the evolving neurological deficits. Pathological analysis revealed Ewing sarcoma. He subsequently underwent chemotherapy and radiation therapy. At the 6-week follow-up, he had improvement in left leg strength without any evidence of tumor residual on imaging. A systematic review identified 80 cases of primary epidural EES. The mean age at presentation was 21.2 years, with 81.3% of patients < 30 years of age. Most patients were initially treated with surgery (86.2%), followed by adjuvant radiotherapy and chemotherapy (77.9%). Survival and progression-free survival at 1 year were 81.1% and 75.0%, respectively. Given the rarity of primary epidural EES, defining common treatment strategies and prognostic markers is essential to guide clinical decision-making and patient counselling. https://thejns.org/doi/10.3171/CASE2635.
An intramedullary spinal cord clear cell meningioma (CCM) is an exceptionally rare diagnosis; there are only 2 similar cases reported in the literature. The authors present a case of an intramedullary spinal cord CCM that was successfully resected with the assistance of sodium fluorescein to guide resection. A 68-year-old male presented with gait instability, decreased sensation, and loss of proprioception in the lower extremities, concerning for thoracic myelopathy. MRI of the thoracic spine revealed an intradural, intramedullary contrast-enhancing mass most concerning for a spinal ependymoma or astrocytoma. Given his progressive neurological decline, need for tissue diagnosis, and tumor cytoreduction, fluorescence-guided resection of the mass was performed. Postoperative pathological analysis demonstrated the presence of polygonal tumor cells with clear cytoplasm that harbored a known pathogenic SMARCE1 frameshift mutation that supported the diagnosis of an intramedullary CCM. The authors present the first reported case of a fluorescence-guided resection of an intramedullary CCM. https://thejns.org/doi/10.3171/CASE251031.
Eosinophilic granuloma (EG) is a localized subtype of Langerhans cell histiocytosis (LCH) that involves infiltration of tissues by a clonal proliferation of Langerhans cells. EG is a rare tumor of the orbit and most commonly presents in childhood. This tumor is known to regress after minimal intervention (including biopsy), and management includes curettage and intralesional corticosteroids. The natural history of EG is not well understood, and true spontaneous regression of the lesion without intervention has rarely been described. Herein, the authors present a unique case of an adult patient with presumed orbitocranial EG with true spontaneous regression over a 4-month period. Biopsy of the residual mass revealed reactive changes and no evidence of neoplasia, consistent with resolved EG. Adult patients with EG may experience regression of the lesion without intervention. https://thejns.org/doi/10.3171/CASE25426.
In patients with drug-resistant epilepsy (DRE) who are not candidates for resective surgery, thalamic neuromodulation targeting structures such as the anterior nucleus of the thalamus (ANT), centromedian nucleus (CM), and pulvinar (PUL) has emerged as a promising therapy. The clinical investigation of these targets' efficacy and side effect profiles is ongoing, complicating discussions between neurosurgeons, neurologists, and patients. The implementation of single-pulse and continuous stimulation protocols to conduct patient-specific side effect screens and generate prognostic biomarkers could offer guidance for target selection. A 32-year-old male with extensive polymicrogyria and DRE underwent stereo-electroencephalography (SEEG) with multisite thalamic sampling to inform neuromodulation target selection. Single-pulse stimulation was conducted to screen for acute sensorimotor effects, followed by continuous (12- to 24-hour) stimulation using clinically relevant parameters. Intolerable paresthesia occurred during CM single-pulse stimulation, leading to its exclusion as a target. Single-pulse and continuous stimulation of the ANT and PUL were well tolerated. PUL stimulation offered superior suppression of epileptiform discharges during sleep. These findings meaningfully informed the selection of the PUL as a neuromodulation target. This case illustrates the safety, feasibility, and utility of patient-specific single-pulse and continuous stimulation assessments during SEEG monitoring to evaluate efficacy and tolerability prior to chronic neuromodulation, particularly for novel thalamic targets. https://thejns.org/doi/10.3171/CASE25947.
Neurofibromatosis type 1 (NF1) is a multisystem neurocutaneous disorder associated with skeletal dysplasia, dural ectasia, and, less commonly, spinal meningoceles. Although these lesions are often asymptomatic, they may progressively enlarge over time, resulting in spinal deformity and compression of adjacent neurovascular and aerodigestive structures. Cervical and cervicothoracic meningoceles are particularly rare and pose unique diagnostic and management challenges. A 43-year-old woman with NF1 presented with progressive gait imbalance and left upper limb dysesthesia and weakness more than 1 decade after initial diagnosis of a right-sided cervical meningocele that had been managed conservatively. Serial imaging over 11 years demonstrated gradual enlargement of a cervicothoracic lateral meningocele, ultimately measuring more than 10 cm, with associated severe kyphoscoliosis, vertebral scalloping, foraminal widening, spinal cord deviation, and displacement of the vertebral and carotid arteries, as well as anterior compression of the esophagus and airway. Neurological deficits correlated with foraminal compression at the C5-T1 levels. Brain MRI additionally revealed bilateral optic pathway gliomas, suggesting a more extensive NF1 phenotype. Given progressive neurological decline and neurovascular compromise, surgical repair of the anterior cervical meningocele was performed, resulting in marked postoperative radiological improvement and relief of mass effect. Spinal meningoceles associated with NF1 may follow an indolent but progressive course over many years, emphasizing the necessity of long-term clinical and radiological surveillance even in initially asymptomatic patients. Cervical involvement, although uncommon, can lead to significant spinal deformity and neurovascular compression. Early recognition of clinical deterioration should prompt timely surgical reassessment. Multidisciplinary management is essential in patients with complex NF1 manifestations, particularly when spinal pathology coexists with other CNS tumors. https://thejns.org/doi/10.3171/CASE26112.
Multiple intracranial aneurysms (MIAs) pose complex management challenges due to their elevated cumulative rupture risk and the potential morbidity associated with staged or multimodal treatment. Single-stage microsurgical strategies have been explored to minimize cumulative procedural risk while providing durable aneurysm exclusion. The "squeeze play" technique, dual ipsilateral pterional and interhemispheric craniotomies performed through a single incision, offers a unified corridor for treating aneurysms arising from both sylvian and interhemispheric fissures. Few reports have detailed its use for treatment of multiple aneurysms. A woman in her 40s with seven unruptured anterior circulation aneurysms underwent single-stage microsurgical clipping using the squeeze play approach. A right-sided pterional craniotomy allowed successful clipping of the M1-M2, M2-M3, A1, and ophthalmic aneurysms, the latter requiring an anterior clinoidectomy and optic nerve unroofing. A parasagittal interhemispheric craniotomy exposed two pericallosal aneurysms and a callosomarginal aneurysm, all of which were clipped safely. Intraoperative indocyanine green angiography and Doppler ultrasonography confirmed complete aneurysm obliteration with preserved vessel patency. Postoperative CT angiography and digital subtraction angiography demonstrated no residual aneurysms, and the patient was discharged home on postoperative day 3 without neurological deficits. This case highlights the feasibility, efficiency, and safety of microsurgery for comprehensive single-stage treatment of MIAs. Dual ipsilateral craniotomies through a single incision allow definitive clipping of both lateral and midline aneurysms while avoiding the cumulative risks of staged surgeries and the long-term recurrence concerns associated with endovascular therapy. Careful patient selection and meticulous microsurgical technique are essential to achieving optimal outcomes. https://thejns.org/doi/10.3171/CASE25985.
Single-position prone lateral lumbar interbody fusion (pLLIF) enables interbody placement, posterior instrumentation, and adjunct decompression to be performed without repositioning. Beyond operative efficiency, prone positioning provides flexible surgical sequencing and intraoperative decision-making. While sequencing might not influence outcomes in most cases, particular scenarios may warrant more careful consideration. Advanced intraoperative neuromonitoring, like transabdominal muscle action potential (TMAP) monitoring, offers real-time feedback and identifies the neurological implications of operative sequencing decisions. Two patients with nearly identical pathology, proximal lumbar canal stenosis and distal degenerative pathology, underwent pLLIF with concomitant proximal decompression but in opposite operative sequences. In the first case, interbody fusion preceded decompression and was associated with TMAP threshold elevations and postoperative motor deficit. In the second case, proximal decompression performed first resulted in stabilization and improvement of TMAP signals, followed by completion of interbody fusion without neurological complication. Aside from surgical sequence, these cases were otherwise comparable. The flexibility of surgical sequencing with prone positioning may be clinically meaningful in patients with proximal canal stenosis. Event-based TMAP monitoring provides real-time insight into sequence dependent neural stress that might otherwise go unrecognized. Thoughtful surgical sequencing and integration of sensitive neuromonitoring enhance intraoperative decision-making and neurological safety. https://thejns.org/doi/10.3171/CASE2680.
Massive brain swelling after cranioplasty (MBSC) is a rare but frequently fatal complication characterized by cerebral edema following cranial vault reconstruction. Evidence suggests that MBSC occurs in patients with chronic intracranial hypotension, often in the setting of severe sinking skin flap (SSF) syndrome after decompressive craniectomy (DC). The authors report a case of MBSC in a 42-year-old man who underwent custom cranioplasty 5 months after DC. Preoperative imaging demonstrated SSF syndrome with a 15-mm midline shift. Within 1 hour after surgery, the patient developed a seizure followed by rapid neurological deterioration. CT of the head revealed diffuse supratentorial and cerebellar edema with a new intraparenchymal hemorrhage. Despite aggressive medical therapy and emergency removal of the implant with re-decompression, the patient sustained profound neurological injury. This case highlights the malignant presentation pattern of MBSC and underscores severe SSF syndrome as a critical preoperative risk state. Sudden restoration of the cranial vault may precipitate a pathological intracranial pressure surge in patients chronically adapted to intracranial hypotension. Cranioplasty timing and seizure activity may impact MBSC risk. Further study is needed to clarify optimal timing strategies and prophylactic antiseizure therapy. Heightened perioperative vigilance and explicit risk counseling may be necessary, as outcomes remain poor once the MBSC cascade is established. https://thejns.org/doi/10.3171/CASE2659.
Endovascular treatment of ruptured intracranial aneurysms can be particularly challenging in patients with a right-sided aortic arch and concomitant carotid artery stenosis, where stable catheterization via conventional transfemoral routes is often impossible. Direct carotid puncture is a potential alternative. However, conventional sheaths can transiently occlude the carotid artery and increase the risk of cerebral ischemia. An 87-year-old patient with subarachnoid hemorrhage due to a ruptured intracranial aneurysm presented with a right-sided aortic arch and severe calcified stenosis of the left common carotid artery. Given the tortuous and stenotic vascular anatomy, transfemoral access was discontinued. Percutaneous direct carotid puncture of the left common carotid artery was performed using an elastic needle with an outer diameter of 1.7 mm. This low-profile access allows microcatheter navigation and successful coil embolization without perioperative ischemic or hemorrhagic complications. Hemostasis was achieved using simple manual compression. When conventional endovascular access is precluded by complex vascular anatomy, particularly in cases complicated by carotid artery stenosis, direct carotid puncture using an elastic needle may offer a safer and less invasive alternative. This approach provides a feasible option in anatomically challenging situations in which standard sheaths would increase the risk of ischemic complications. https://thejns.org/doi/10.3171/CASE25869.
Carotid webs are increasingly recognized as a significant cause of cryptogenic stroke in young adults, yet they remain frequently underdiagnosed due to their subtle radiographic appearance and atypical presentations. The natural history of untreated carotid webs includes high rates of recurrent ipsilateral ischemic events despite optimal medical therapy. The authors present the case of a 44-year-old man with four recurrent right hemispheric ischemic events over 5 years. Despite multiple angiographic studies, an underlying carotid web was initially misinterpreted. Digital subtraction angiography ultimately revealed a subtle posterolateral carotid web. Prior to endarterectomy, intraoperative ultrasound uniquely visualized a large thrombus adherent to the web, a critical finding not appreciated on preoperative angiography. Successful en bloc removal of the web and thrombus was performed with histopathological confirmation. The patient remained stroke free at the 1-year follow-up. Atypical carotid webs may lack classic radiographic features and can be misclassified on noninvasive imaging. Intraoperative ultrasound provides real-time assessment of thrombus burden not visible on preoperative angiography, allowing for improved surgical planning. This case demonstrates that web-associated thrombi are dynamic and may not be apparent even on high-resolution angiography performed shortly before surgery. Surgical intervention with intraoperative ultrasound guidance offers definitive treatment and excellent long-term outcomes. https://thejns.org/doi/10.3171/CASE2610.
Petrous apex cephaloceles (PACs) are infrequent lesions mostly diagnosed as incidental findings. Rare cases may manifest as trigeminal neuralgia (TN). A 51-year-old female presented with a 19-year history of TN. Investigative imaging revealed herniation of the trigeminal nerve into Meckel's cave through a right-sided petrous apex defect. The patient underwent a right preauricular middle cranial fossa craniotomy and subtemporal extradural approach to access Meckel's cave. The nerve was released and repositioned, and a fat graft was used to obliterate the petrous apex defect to prevent recurrence. The procedure successfully relieved the patient's severe pain. At the 6-week postoperative follow-up visit, the patient was free from TN symptoms with no surgical complications. At 18 months, the patient was still free from TN symptoms. To the best of the authors' knowledge, there are few reported cases of TN caused by PACs in the literature. This study highlights the importance of considering PACs as a rare but potentially reversible cause of TN, especially in patients with refractory symptoms whose imaging demonstrates no neurovascular conflict. Moreover, the effectiveness of surgical intervention in treating this condition is reinforced. https://thejns.org/doi/10.3171/CASE25460.
Sacroiliac (SI) joint dysfunction is a frequently underrecognized source of low back pain, implicated in 15%-30% of cases across select populations. Unilateral SI joint fusion remains the most commonly performed technique, utilizing either iliosacral screws or, more recently, through-and-through (TNT) screws. A 65-year-old woman with a history of failed right-sided SI joint fusion underwent revision surgery with bilateral TNT screw fixation due to worsening symptoms. Follow-up imaging confirmed solid right-sided arthrodesis. However, progressive haloing and sclerosis were observed around the left iliac portion of the cephalad screw. This case represents the first reported instance of persistent motion and screw haloing using TNT screw fixation when using two spanning screws. These findings highlight a potential limitation of TNT constructs due to load transfer, stress shielding, and asymmetric osseous integration, particularly in patients with a history of prior unilateral SI joint fusion. https://thejns.org/doi/10.3171/CASE25668.
Compared to dural arteriovenous fistulas (AVFs), the pathogenesis of extradural AVFs is unclear. Furthermore, the outcomes of surgical and endovascular treatments are inferior to those of dural AVFs, and in some cases, there are reports of poor outcomes. A 74-year-old male hemodialysis patient presented with gradually progressive gait disturbance. MRI showed high T2 signal intensity in the lower spinal cord, and angiography revealed a dural AVF. The patient was referred to the authors' hospital. Multiple small arteries were found to have refluxing veins in the dura at T12-L1 on the right side, and a diagnosis of epidural AVF was made, leading to direct surgery. During exoscopic microsurgery, the venous pouch located on the lateral ventral side was exposed, and intradural and extradural hemodynamics were confirmed using indocyanine green (ICG) videoangiograhy, followed by complete coagulated occlusion. Postoperatively, the patient's symptoms improved. There have been few cases of epidural AVF treated with exoscopic ICG videoangiography for intradural and extradural observation and healing. https://thejns.org/doi/10.3171/CASE25865.
Microvascular decompression (MVD) is a well-established treatment for compressive cranial neuralgias such as trigeminal neuralgia and hemifacial spasm. The vagus nerve (cranial nerve [CN] X), with its extensive parasympathetic innervation to the gastrointestinal (GI) system, has less clearly defined neuropathic symptomatology, and MVD of CN X has only been reported once. The authors report a unique case of treatment-refractory GI distress that resolved completely following CN X MVD. A 32-year-old male with a 13-year history of hemifacial spasm also experienced chronic, debilitating GI distress characterized by sudden, painful abdominal cramping and diarrhea. Despite extensive workup, including three colonoscopies, no clear etiology was found. During MVD for his facial nerve, a large vertebral artery loop was incidentally found significantly displacing CN X. Both nerves were decompressed. Both the patient's hemifacial spasms and GI symptoms resolved immediately, and this has persisted for more than 5 years of follow-up. While vagal injury (including intentionally via vagotomy) results in gastroparesis, the authors propose that chronic CN X compression may induce a "hyperactive rhizopathy" resulting in symptoms of overactive peristalsis. CN X compression may be an underrecognized, reversible etiology of chronic GI distress, and clinicians should consider the possibility of neurovascular conflict in this patient population. https://thejns.org/doi/10.3171/CASE2688.
Presacral ganglioneuromas are extremely rare tumors, with only 37 documented cases in the literature. For a successful outcome, resection is crucial because it is currently the only effective treatment option. With the advancement in resection techniques, robotic surgery is now being utilized for achieving optimal surgical outcomes, with only 2 previous cases being documented in the literature for the resection of presacral ganglioneuroma. Since ganglioneuromas are benign, radiation therapy and adjuvant chemotherapy are not recommended; however, frequent monitoring is required to detect possible local recurrences early. The authors present the case of presacral ganglioneuroma in a 62-year-old male who underwent robot-assisted excision. Robot-assisted surgery allowed for a positive surgical outcome, including the absence of intra- or postoperative complications and a decreased length of hospital stay. The presacral location poses challenges to resection due to many exiting nerve roots. Robotic surgery facilitates positive patient outcomes for tumors in challenging anatomical locations like the presacral location. https://thejns.org/doi/10.3171/CASE25462.
Medically refractory seizures occur in up to 30% of patients with epilepsy. Treatments may include neuromodulation, ablative procedures, and stereotactic surgery. Cutting-edge technology, such as neuroimaging, anatomical mapping, electroencephalography, and augmented reality (AR), assist in localization and safer treatment planning. A 26-year-old male with focal onset epilepsy underwent phase II monitoring with stereo-electroencephalography (sEEG) that localized his seizure focus to the right supplementary motor area (SMA)/pre-SMA. A combination of traditional navigation, phase-reversal electrocorticography, and AR was used to perform anatomical localization and verification to assist with craniotomy and resection. He is now seizure free with no significant neurological deficit 9 months after surgery. AR has multiple applications in neurosurgery, including preoperative planning, anatomical verification, and intraoperative guidance. In this case, AR navigation provided real-time 3D overlays of MRI- and CT-derived patient anatomy onto the surgical field, allowing visualization of segmented cortical surface anatomy, vascular structures, white matter tracts, and electrodes via voice commands. This enabled precise mapping of deep-seated anatomy and electrode trajectories without increasing operative time or complication risk. Given the early stage of the technology, AR was used adjunctively with neuronavigation during SMA/pre-SMA resection and demonstrated localization concordant with traditional mapping techniques. https://thejns.org/doi/10.3171/CASE25611.
Cauda equina syndrome (CES) with sexual dysfunction is an uncommon but serious complication of lumbar disc herniation. Giant lumbar disc herniations, defined as occupying more than 50% of the spinal canal, can cause severe neural compression. Delayed decompression in CES is traditionally associated with poor neurological and autonomic recovery. A 36-year-old man presented with a 1-year history of low back pain and progressive radiculopathy, followed by 3 months of incomplete CES manifested by urinary dysfunction, constipation, saddle hypoesthesia, sexual dysfunction, and right foot drop. MRI revealed a giant L4-5 disc extrusion with a cranially migrated sequestered fragment measuring nearly 10 cm in total length and extending 1.7 cm behind the L4 vertebral body, resulting in marked thecal sac compression. The patient underwent delayed microsurgical excision of the disc fragment. Postoperatively, back and leg pain improved immediately. Urinary symptoms resolved by 24 months, and sexual function fully recovered by 40 months, whereas motor deficits and muscle wasting showed minimal improvement. Meaningful long-term recovery of bladder and sexual function is possible in incomplete CES despite delayed decompression, suggesting that neurological completeness at presentation may be a stronger prognostic factor than timing alone. https://thejns.org/doi/10.3171/CASE2647.
Prostate cancer is a common malignancy in men and usually presents with elevated prostate-specific antigen (PSA) levels and metastases to the bones or lymph nodes. Brain metastases are rare, occurring in less than 1% of cases. Concurrent elevation of carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) is also uncommon. A 61-year-old man presented with left hemiparesis and cognitive decline. Laboratory tests revealed elevated PSA, CEA, and CA19-9 levels. Imaging revealed a cystic frontal lobe mass, lung nodules, pelvic lymphadenopathy, and a prostatic lesion. MRI confirmed a 5-cm right frontal mass with heterogeneous enhancement and edema. A prostate biopsy revealed adenocarcinoma positive for CEA and CA19-9. Endoscopy revealed no gastrointestinal malignancies. Craniotomy and histopathological examination confirmed the diagnosis of adenocarcinoma. Immunohistochemical analysis revealed CEA positivity, partial CA19-9 positivity, strong NKX3.1 positivity, and PSA negativity. Postoperatively, the patient received androgen deprivation therapy with leuprorelin acetate and darolutamide, along with 5 cycles of docetaxel chemotherapy. At the 24-month follow-up, he remains neurologically stable without recurrence. Brain metastases from prostate cancer with elevated CEA and CA19-9 are rare. Although these markers often indicate a poor prognosis, this patient achieved a favorable outcome with multimodal treatment. https://thejns.org/doi/10.3171/CASE25735.
Trigeminal neuralgia (TN) is commonly caused by a vascular compression of the trigeminal nerve (classical TN). Due to the high frequency of this compression at the nerve's root entry zone, a misunderstanding has arisen in the literature that this location is the only site that can cause TN. The present case demonstrates that TN can be caused by compression anywhere along the nerve-even in the face. A 15-year-old female presented with medically refractory left TN. MRI revealed no neurovascular conflict at the root entry zone, but ultrasound revealed a lymphatic malformation in her face. After the lesion was sclerosed with bleomycin, her TN pain improved significantly. Trigeminal nerve compression distal to the root entry zone, although uncommon, is a treatable cause of TN. Treatment for classical TN should consider the full anatomical course of the nerve and potential compression points. This case challenges the conventional understanding that TN is exclusively caused by compression at its more vulnerable root entry zone. https://thejns.org/doi/10.3171/CASE25973.
Trigeminal neuropathic pain (TNP), particularly posttraumatic TNP (PTTN), is often refractory to medical therapy and difficult to manage surgically. Although radiofrequency thermoablation (RFA) of the gasserian ganglion is established, peripheral nerve RFA remains underutilized, particularly in anatomically complex cases. A 62-year-old man developed severe left maxillary (V2) facial pain following sinus surgery, refractory to multiple pharmacological therapies and prior gasserian balloon rhizotomy. A diagnostic infraorbital nerve block produced significant temporary relief, supporting a peripheral pain generator and RFA consideration. An initial infraorbital nerve RFA performed with fluoroscopic guidance failed to provide durable benefit. A subsequent CT-guided infraorbital nerve RFA resulted in marked pain reduction. The patient later developed localized recurrent dysesthesia, prompting a third CT-guided, navigation-assisted RFA with sustained improvement. At the last follow-up (8, 6, and 3 months after the first, second, and third RFAs, respectively), his visual analog scale pain score improved from 10 to 2, with approximately 80% reduction in pain flares and significant quality of life improvement. CT-guided infraorbital nerve RFA is a minimally invasive and effective option for refractory PTTN. Peripheral RFA, particularly when combined with advanced image guidance and potentially awake mapping, should be considered when central interventions fail or are contraindicated. https://thejns.org/doi/10.3171/CASE25553.