Primary osseous tumors of the pediatric spinal column: review of pathology and surgical decision making.

Spinal column tumors are rare in children and young adults, accounting for only 1% of all spine and spinal cord tumors combined. They often present diagnostic and therapeutic challenges. In this article, the authors review the current management of primary osseous tumors of the pediatric spinal column and highlight diagnosis, management, and surgical decision making.

Intraspinal cervicothoracic junction chondrosarcoma: illustrative case.

BACKGROUND: Chondrosarcoma is an uncommon spinal tumor that can present as an extraskeletal mass. Rarely, these tumors present as dumbbell tumors through the neural foramina, mimicking schwannomas or neurofibromas. OBSERVATIONS: A 46-year-old female presented with 2 years of worsening right-arm radiculopathy. Magnetic resonance imaging of the thoracic spine revealed a peripherally enhancing extramedullary mass through the right T1 foramen and compressing the spinal cord. Computed tomography showed the mass to be partially calcified. She underwent C7-T2 laminectomy and C6-T3 posterior instrumented fusion with gross-total resection of an extradural mass. Pathology revealed a grade I chondrosarcoma. Her symptoms improved postoperatively, with some residual right-arm radicular pain. LESSONS: Intraspinal extradural dumbbell conventional chondrosarcoma is rare, with only 9 cases, including ours, reported. Patient ages range from 16 to 72 years old, and male sex is more common in these cases. The most common location is the thoracic spine, and our case is the only reported one in the cervicothoracic junction. These tumors often mimic schwannomas on imaging, but chondrosarcoma should remain in the differential diagnosis, because management of these tumors differs. Chondrosarcoma may benefit from more aggressive resection, including en bloc resection, and may require adjuvant radiotherapy.

Tandem cranial and spinal cerebrospinal fluid leaks presenting with otogenic tension pneumocephalus: illustrative case.

BACKGROUND: Cranial and spinal cerebrospinal fluid (CSF) leaks are associated with opposite CSF fluid dynamics. The differing pathophysiology between spontaneous cranial and spinal CSF leaks are, therefore, mutually exclusive in theory. OBSERVATIONS: A 66-year-old female presented with tension pneumocephalus. The patient underwent computed tomography (CT) scanning, which demonstrated left-sided tension pneumocephalus, with an expanding volume of air directly above a bony defect of the tegmen tympani and mastoideum. The patient underwent a left middle fossa craniotomy for repair of the tegmen CSF leak. In the week after discharge, she developed a recurrence of positional headaches and underwent head CT. Further magnetic resonance imaging of the brain and thoracic spine showed bilateral subdural hematomas and multiple meningeal diverticula. LESSONS: Cranial CSF leaks are caused by intracranial hypertension and are not associated with subdural hematomas. Clinicians should maintain a high index of suspicion for intracranial hypotension due to spinal CSF leak whenever "otogenic" pneumocephalus is found. Close postoperative follow-up and clinical monitoring for symptoms of intracranial hypotension in any patients who undergo repair of a tegmen defect for otogenic pneumocephalus is recommended.

Ocular needlefish injury with cavernous sinus thrombosis and carotid-cavernous fistula: illustrative case.

BACKGROUND: The Belonidae family of fish has been implicated in various penetrating injuries; to date, however, there have been limited reports of brain injury due to this species. OBSERVATIONS: The authors present the case of a young patient who suffered an ocular penetrating injury from a needlefish with a resultant cavernous sinus thrombosis and concomitant carotid-cavernous fistula. This case highlights the interdisciplinary management of this rare condition through a strategy of anticoagulation titration to the endpoint of fistula closure. LESSONS: Through this report the importance of a high index of suspicion for neurovascular injury and fistula formation in penetrating ocular injuries is highlighted as well as the importance of interdisciplinary management of patients with such injuries and their sequelae.

Durability of an endoscopic management strategy for recurrent choroid plexus carcinoma with a comprehensive molecular characterization: illustrative case.

OBJECTIVE: Choroid plexus carcinoma (CPC) is a rare, primarily intraventricular neoplasm. Extent of resection correlates with improved outcomes but is limited due to tumor vascularity and size. Evidence on optimal surgical management and molecular drivers of recurrence remains limited. Here the authors characterize a case of multiply recurrent CPC treated with sequential endoscopic removals over 10 years and highlight its genomic properties. OBSERVATIONS: Five years after standard treatment, a 16-year-old female presented with a distant intraventricular recurrence of CPC. Whole exome sequencing revealed NF1, PER1, and SLC12A2 mutations, FGFR3 gain, and no TP53 alterations. Repeat sequencing on recurrences 4 and 5 years later showed persistent NF1 and FGFR3 alterations. Methylation profiling was consistent with plexus tumor, subclass pediatric B. Short-term magnetic resonance imaging detected four total isolated recurrences, all treated with complete endoscopic resections at 5, 6.5, 9, and 10 years after initial diagnosis. Mean hospital stay for all recurrences was 1 day with no complications. LESSONS: The authors describe a patient with four isolated recurrences of CPC over a decade, each treated with complete endoscopic removal, and identify unique molecular alterations that persisted without TP53 alterations. These outcomes support frequent neuroimaging to facilitate endoscopic surgical removal following early detection of CPC recurrence.

Sacral myolipoma with involuntary contraction causing tethered cord syndrome: illustrative case.

BACKGROUND: Spinal lipomas sometimes involve various ectopic tissues originating from the ectoderm, mesoderm, and endoderm in the process of morphological development. OBSERVATIONS: A 29-year-old male patient with myolipoma of the conus medullaris at the S2 and S3 levels was described. The unusual finding, involuntary muscle contraction, was presented in an operative video and a literature review. In the present case, sacral myolipoma with involuntary contraction caused tethered cord syndrome in adulthood, and untethering surgery resolved continuous buttock and leg pain. LESSONS: This rare finding is considered a surgical indication for adult patients with myolipoma.

Robot-assisted atlantoaxial fixation: illustrative cases.

BACKGROUND: Placing screws in the high cervical spine can be challenging because of the vital anatomical structures located in that region. Precision and accuracy with screw placement is needed. The use of robotics in the cervical spine has been described before; however, here the authors describe the use of a new robotic setup. OBSERVATIONS: The authors describe 2 cases of robot-assisted placement of C2 pars screws and C1-2 transarticular screws. The operative plans for each patient were as follows: placement of C2 pars screws with C2-4 fusion for hangman's fracture and placement of C1-2 transarticular screws for degenerative disease. Intraoperative computed tomography (CT) was used to plan and navigate the screws. Postoperative CT showed excellent placement of hardware. Both patients presented for initial postoperative clinic visits with no recurrence of prior symptoms. LESSONS: Intraoperative robotic assistance with instrumentation of the high cervical spine, particularly C2 pars and C1-2 transarticular screws, may ensure proper screw placement and help avoid injury.

Delayed cerebral pseudoaneurysm following surgical and combined-modality therapy for glioblastoma multiforme: illustrative case.

BACKGROUND: Post-radiation therapy and chemotherapy cerebral pseudoaneurysms are rare entities. Within previous tumor treatment areas on nonvascular imaging, they are potentially confused as recurrent tumor. OBSERVATIONS: A 61-year-old man was a long-term survivor of glioblastoma multiforme whose treatment consisted of open biopsy followed by radiotherapy to 60 Gy and systemic carmustine. On surveillance imaging, enlargement of a posttreatment cyst and new enhancing lateral "mural nodule" was first noticed approximately 16 years after initial treatment. Over 12 months, both continued to enlarge. Initially referred to as recurrence, subsequent angiography showed the mural nodule to be an unruptured distal middle cerebral artery pseudoaneurysm within the previous tumor bed. The patient underwent repeat craniotomy for clipping of the aneurysm and biopsy of the cyst wall, which was negative for malignancy. LESSONS: Delayed pseudoaneurysms following radiation therapy and chemotherapy for malignant brain tumors are rare but have been previously reported. Their appearance on cross-sectional imaging can mimic recurrence, and they should be kept in the differential of new, circumscribed enhancement within such treatment areas.

Giant anterior sacral meningocele associated with hydroureteronephrosis and renal injury: illustrative case.

BACKGROUND: Anterior sacral meningocele (ASM) is a defect in the closure of the neural tube. Patients can be asymptomatic or present with genitourinary, neurological, reproductive, or colorectal dysfunction. Magnetic resonance imaging (MRI) is the gold standard test because it can assess communication between the spinal subarachnoid space and the lesion and identify other abnormalities. Surgical correction is the definitive treatment because untreated cases have a mortality rate of more than 30%. OBSERVATIONS: A 24-year-old woman with Marfan syndrome presented with polyuria, recurrent urinary tract infections, and renal injury for 3 months along with a globose abdomen, with a palpable mass in the middle and lower third of the abdomen that was massive on percussion. MRI showed an ASM consisting of two cystic lesions measuring 15.4 × 14.3 × 15.8 and 6.7 × 6.1 × 5.9 cm, respectively, compressing the distal third of the right ureter and causing a hydroureteronephrosis. Drainage and ligature of the cystic lesion were performed. The urinary outcome was excellent, with full recovery after surgery. LESSONS: ASM should be suspected in all abdominal masses with progressive symptoms in the setting of Marfan syndrome. Computed tomography and MRI are important to investigate genitourinary anomalies or other types of dysraphism to guide the best surgical approach.

Endoscopic endonasal approach for simultaneously treating a pituitary adenoma coexisting with a paraclinoid aneurysm: illustrative case.

BACKGROUND: There is a certain incidence of pituitary adenomas coexisting with intracranial aneurysms, but a concurrent therapeutic strategy of tumor removal and aneurysm clipping via endoscopic endonasal approach is rarely reported. The indications and limitations of endoscopic endonasal approach surgery for this type of lesions are worth discussing. OBSERVATIONS: The case of a pituitary tumor coexisting with a paraclinoid aneurysm was reviewed. Using an endoscopic endonasal approach, the pituitary adenoma was completely excised with extrapseudocapsular separation technique, the aneurysm was clipped at the same time, and the skull base defect was reconstructed in multilayer fashion. No tumor recurrence was found, and aneurysm clipping was complete at the 6-month follow-up after surgery. LESSONS: For patients harboring a pituitary adenoma with a selected paraclinoid aneurysm, simultaneous tumor resection and aneurysm clipping via endoscopic endonasal approach are feasible. This strategy has the advantages of saving medical resources, promoting the patient's rapid postoperative recovery, and reducing possible antiplatelet therapy after interventional therapy. However, surgery needs to strictly follow the indications in experienced hands, and the therapeutic effect needs to be verified by more cases and longer follow-up results.

Benign eccrine spiradenoma imitating a nerve sheath tumor: illustrative case.

BACKGROUND: Benign eccrine spiradenoma is a rare tumor arising from the sweat glands and is a pathology that is almost never encountered in routine neurosurgical practice. Although this is a rare pathology, it is one that should be included in the differential diagnosis for a patient presenting with a painful, subcutaneous mass, because it can guide further treatment considerations. OBSERVATIONS: The authors present a case of benign eccrine spiradenoma that mimicked a nerve sheath tumor in clinical presentation, imaging characteristics, and gross appearance. LESSONS: Complete local excision of these lesions is the gold standard treatment, because they are painful, and there are reports of local recurrence and malignant degeneration with incomplete resection. For this reason, neurosurgeons should be sure to include this in the differential diagnosis of a patient with a painful, subcutaneous mass, because it may help to guide management decisions.

Minimally invasive endoscopic fenestration of a spinal arachnoid cyst in a child with tetrasomy 18p: illustrative case.

BACKGROUND: Spinal arachnoid cysts (SAC) are rare, especially in children. Patients can be asymptomatic or present symptoms of spinal cord compression. In this latter case, surgery is indicated to relieve the compression. Different surgical techniques have been described to treat these cysts, endoscopic or endoscopy-assisted fenestration being the least invasive. Tetrasomy 18p describes the condition in which two copies of the short arms of chromosome 18 are present. It is an extremely rare pathology with a variable phenotype, including 100% of cases cognitive impairment and developmental delay. Different central nervous system (CNS) abnormalities have been found in these patients. OBSERVATIONS: The authors describe the case of a 3-year-old boy with a tetrasomy 18p and a wide spinal arachnoid cyst that received an endoscope-assisted treatment with a significantly improved motor outcome. LESSONS: Tetrasomy 18p is an extremely rare pathology and different CNS abnormalities have been described in association with, but to date spinal arachnoid cyst has never been reported. These children typically show global hypotonia and cognitive impairment. The authors recommend a thorough neurological assessment with cranio-spinal magnetic resonance imaging to rule out any possible malformation that could be improved by surgery.

Multifocal intradural extramedullary ependymoma, MYCN amplified: illustrative case.

BACKGROUND: Ependymomas are the most frequent tumors of the adult spinal cord, representing 1.9% of all central nervous system tumors and 60% of spinal cord tumors. Spinal ependymomas are usually solitary, intramedullary lesions. While intradural extramedullary (IDEM) ependymomas are infrequent, multifocal IDEM ependymomas are exceptionally rare. OBSERVATIONS: The authors reported the first case in the literature of a patient diagnosed with multifocal IDEM ependymomas who was treated with tumor resection and brain and spinal radiotherapy. The patient presented with a 10-day history of bilateral leg numbness extending to the umbilicus and gait instability. Magnetic resonance imaging (MRI) studies revealed multiple enhancing nodular nodules throughout the entire spinal canal. Brain MRI revealed no abnormal lesions. A World Health Organization grade II ependymoma was confirmed histologically. At 31 months postoperatively, the patient remained clinically asymptomatic. Although cervical and thoracic MRI revealed stable intradural nodules and several areas of leptomeningeal enhancement, no malignant cells were seen in the cerebrospinal fluid (CSF). He underwent genetic testing to determine the appropriate chemotherapeutic agent if activation of the tumor should arise. LESSONS: Because complete resection of multifocal IDEM ependymomas is not feasible, continued monitoring with brain and spine MRI is warranted to detect potential tumor dissemination in the CSF.

Strongyloides hyperinfection syndrome due to corticosteroid therapy after resection of meningioma: illustrative case.

BACKGROUND: Strongyloidiasis is an underdiagnosed and preventable life-threatening disease caused by infection with the helminth Strongyloides stercoralis. Chronic asymptomatic infection can be sustained for decades, and immunosuppression can lead to disseminated infection, with a mortality rate of 70%-100%. In the neurosurgical population, corticosteroids are the most consistent cause of hyperinfection. OBSERVATIONS: The authors present the case of a 33-year-old woman of Paraguayan origin who was diagnosed with sphenoid planum meningioma and treated with a high dose of corticosteroids on the basis of the diagnosis. She underwent surgery, and pathological anatomy reflected grade I meningioma. After the surgery, she started with a history of dyspnea, productive cough, fever, and urticarial rash. Later, she presented with intestinal pseudo-obstruction and bacterial meningitis with hydrocephalus. Serology was positive for Strongyloides (enzyme-linked immunosorbent assay), and she was diagnosed with hyperinfection syndrome. Ivermectin 200 µg/kg daily was established. LESSONS: It may be of interest to rule out a chronic Strongyloides infection in patients from risk areas (immigrants or those returning from recent trips) before starting treatment with corticosteroids.

Intracranial tuberculoma: a rare complication of extrapulmonary tuberculosis. Illustrative case.

BACKGROUND: Intracranial tuberculomas are rare entities commonly seen only in low- to middle-income countries where tuberculosis remains endemic. Furthermore, following adequate treatment, the development of intracranial spread is uncommon in the absence of immunosuppression. OBSERVATIONS: A 22-year-old man with no history of immunosuppression presented with new-onset seizures in the setting of miliary tuberculosis status post 9 months of antitubercular therapy. Following a 2-month period of remission, he presented with new-onset tonic-clonic seizures. Magnetic resonance imaging demonstrated interval development of a mass concerning for an intracranial tuberculoma. After resection, pathological analysis of the mass revealed caseating granulomas within the multinodular lesion, consistent with intracranial tuberculoma. The patient was discharged after the reinitiation of antitubercular medications along with a steroid taper. LESSONS: To the best of the authors' knowledge, this case represents the first instance of intracranial tuberculoma occurring after the initial resolution of a systemic tuberculosis infection. The importance of retaining a high level of suspicion when evaluating these patients for seizure etiology is crucial because symptoms are rapidly responsive to resection of intracranial tuberculoma masses. Furthermore, it is imperative for surgeons to recognize the isolation steps necessary when managing these patients within the operating theater and inpatient settings.

Dramatic response to targeted therapy in an aggressive olfactory neuroblastoma: illustrative case.

BACKGROUND: Olfactory neuroblastomas are rare sinonasal tumors that arise from the olfactory epithelium. The authors presented a case of an olfactory neuroblastoma with extensive cranial invasion that demonstrated dramatic response to sorafenib, a tyrosine kinase inhibitor. OBSERVATIONS: A 54-year-old man with history of prostate cancer and melanoma presented with left-sided proptosis and was found to have a 6.5-cm Kadish stage D olfactory neuroblastoma with cranial invasion that was refractory to chemotherapy and everolimus. However, it demonstrated dramatic response to sorafenib, causing extensive skull base defects that prompted operative repair. Genomic analysis of the tumor revealed mutations in TSC1 and SUFU. The patient developed disease progression with liver metastases 35 months after starting sorafenib, prompting a change to lenvatinib. He experienced progression of his olfactory neuroblastoma 10 months following this change and died in hospice 1 month later. LESSONS: The authors reviewed the clinical presentation and management of a large olfactory neuroblastoma with dramatic response to sorafenib. They highlighted prior uses of targeted therapy in the management of refractory olfactory neuroblastoma within the context of current standard treatment regimens. Targeted therapies may play a vital role in the management of refractory olfactory neuroblastoma.

Spinal glomus AVM presenting solely with groin pain: illustrative case.

BACKGROUND: Spinal glomus arteriovenous malformations (AVMs) are rare and can cause neurological morbidity due to spinal hemorrhage, venous hypertension, or mass effect. OBSERVATIONS: The authors presented a rare case of spinal glomus AVM presenting with groin pain due to nerve root compression by a feeder aneurysm. A 41-year-old woman was referred to the hospital with initial right groin pain that had worsened over 2 months. Magnetic resonance imaging showed intra- and extramedullary abnormal flow voids at the T11-12 level, and spinal angiography revealed an intramedullary AVM, with extramedullary protrusion of an aneurysm on the feeder vessel, which arose from the sulcal artery of the anterior spinal artery. Because compression of the right L1 nerve root by the aneurysm was the likely cause of the patient's pain, endovascular embolization was performed. The feeder aneurysm disappeared after partial n-butyl 2-cyanoacrylate embolization, and the groin pain disappeared immediately after treatment. Her clinical status has been stable with no recurrence during 1 year of follow-up. LESSONS: This is the first report of glomus-type AVM presenting with radiculopathy alone. One should not overlook the possibility of spinal AVM among patients with groin pain.

Use of virtual magnetic resonance imaging to compensate for brain shift during image-guided surgery: illustrative case.

BACKGROUND: Maximal safe resection is the paramount objective in the surgical management of malignant brain tumors. It is facilitated through use of image-guided neuronavigation. Intraoperative image guidance systems use preoperative magnetic resonance imaging (MRI) as the navigational map. The accuracy of neuronavigation is limited by intraoperative brain shift and can become less accurate over the course of the procedure. Intraoperative MRI can compensate for dynamic brain shift but requires significant space and capital investment, often unavailable at many centers. OBSERVATIONS: The authors described a case in which an image fusion algorithm was used in conjunction with an intraoperative computed tomography (CT) system to compensate for brain shift during resection of a brainstem hemorrhagic melanoma metastasis. Following initial debulking of the hemorrhagic metastasis, intraoperative CT was performed to ascertain extent of resection. An elastic image fusion (EIF) algorithm was used to create virtual MRI relative to both the intraoperative CT scan and preoperative MRI, which facilitated complete resection of the tumor while preserving critical brainstem anatomy. LESSONS: EIF algorithms can be used with multimodal images (preoperative MRI and intraoperative CT) and create an updated virtual MRI data set to compensate for brain shift in neurosurgery and aid in maximum safe resection of malignant brain tumors.

Spinal intraosseous arteriovenous fistulas with perimedullary drainage associated with vertebral compression fracture: illustrative case.

BACKGROUND: Although osseous involvement is occasionally observed in spinal epidural arteriovenous fistulas (AVFs) or seen as a part of diseases of spinal arteriovenous metameric syndrome, purely intraosseous spinal AVFs are extremely rare. Their clinical and imaging characteristic features are not well known. The authors present a case of purely intraosseous AVFs associated with compression fracture. OBSERVATIONS: A 76-year-old man presented with back pain and progressive myelopathy. Computed tomography showed compression fracture of the T12 vertebral body and dilatation of perimedullary veins. Spinal angiography revealed an intraosseous AVF at the T12 spine level, which was fed by multiple feeders of ventral somatic branches and drained into the paravertebral and perimedullary veins. The intraosseous AVF was completely occluded by the combined techniques of transarterial and transvenous embolization with glue and a coil. The symptoms disappeared within 1 month after embolization. LESSONS: Although extremely rare, spinal intraosseous AVFs can develop after compression fracture and cause congestive myelopathy. Combined transarterial and transvenous embolization is useful for the specific case of spinal intraosseous AVFs with both paravertebral and perimedullary drainage.

Primary isolated skull base eosinophilic granuloma confined to the anterior clinoid process: illustrative case.

BACKGROUND: Solitary eosinophilic granuloma (EG) occurs anecdotally in the skull base region, and it has been described in only three previous publications. The authors report the first case of EG of the anterior clinoid process (ACP), which was confined to the ACP and presented with decreased vision. OBSERVATIONS: A 38-year-old woman presented with decreased vision of the left eye of 5 months' duration. Her visual acuity was 3/10, other neurological examinations were intact, and there were no other osseous or soft tissue lesions. The lesion was excised using a left-sided craniotomy and transdural clinoidectomy, decompressing the optic nerve both intra- and extradurally. The lesion was characteristic for EG, and no recurrence was detected after 2 years. LESSONS: EG can be confined to the ACP and impair vision. Imaging studies are sensitive but not specific, and surgical decompression is both diagnostic and treatment oriented. Close observation and even adjuvant therapy may be indicated in similar cases.