Primary ectopic extradural and extraspinal meningiomas are rare. We present a unique case of this type of meningioma in the brachial plexus. A 25-year-old man consulted us because of neuropathic supraclavicular pain and the appearance of a supraclavicular mass whose volume had increased. Clinical examination found paresis of the deltoid, biceps brachii and brachialis muscles rated as M4 (MRC) and a strong Tinel sign at the supraclavicular fossa, over the palpable mass. There was no sign pointing towards central nervous system involvement or altered general condition. MRI revealed a mass measuring 53 × 24 mm invading the C5-C6 plexus roots and the primary upper trunk, but not the bone or spinal area. This lesion was hyperintense on DWI/ADC, hyperintense on T2 with hypointense spots, and hypointense on T1 with intense heterogeneous gadolinium enhancement. Excisional biopsy was done 6 months after symptoms started. The tumor had developed at the C5 root, which was fibrous and at the C6 root, which was grossly normal. Anatomical pathology confirmed the WHO grade 1 meningioma, meningothelial and psammomatous histological subtypes. At 6 months, a follow-up MRI found no postoperative tumor remnants or recurrence. During the postoperative course, persistent paralysis of the deltoid muscle at 5 months justified a nerve transfer. This is a rare case of ectopic extraspinal and extradural meningioma of the brachial plexus. The diagnosis of an ectopic meningioma must be considered when a patient presents with a brachial plexus tumor causing neurological deficits. The extradural nature is not sufficient to rule out this diagnosis.

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.
METHODS: 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.
CONCLUSIONS: 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.

Ventriculoperitoneal (VP) shunt surgeries are common neurosurgical procedure for hydrocephalus. Subdural hematoma (SDH) and extradural hematoma (EDH) are rare but potentially life-threatening complications following VP shunt surgeries. We are describing probably the first case in which a 12-year-old boy presented to the emergency room in altered sensorium and gradual onset quadriparesis following multiple shunt revision procedures done in an outside hospital. Computed tomography head showed chronic right-sided frontotemporoparietal chronic SDH and parietal dominant EDH simultaneously with multiple shunt systems in ventricles. Patient was taken for surgery in emergency and emergent evacuation of hematoma was done. Patient improved in the postoperative period. In this case report we will make an attempt to describe a rare complication of VP shunt surgery and possible mechanisms responsible for it.

Intracranial dermoid cysts are rare dysembryonic tumors of benign nature. These are uncommon in adults. If present, they are usually located in the midline or along the lines of embryonic fusion. The posterior fossa region is an infrequent site. Extradural or interdural locations are even more rare. In this case report, the authors report a laterally located large posterior fossa right cerebellar convexity interdural and extradural dermoid cyst over the sigmoid sinus. It was managed by totally extradural maximum possible safe decompression with microneurosurgical technique. The authors share their experience of addressing this rare pathology at the rarest location with unusual imaging findings.

BACKGROUND: Spinal dural arteriovenous fistula is the most common spinal vascular malformation. It usually presents with neurological deficits due to venous congestive myelopathy. Sometimes, however, the symptoms are radicular and can imitate those of a disc hernia or synovial cyst.
METHODS: In this illustrated case, a 34-year-old male patient presented with radicular pain due to nerve root compression. In the magnetic resonance imaging (MRI) examination of the spine, a synovial cyst was suspected, so the patient underwent no further examination before surgery. Intraoperatively, the authors were surprised to see a vascular malformation, which was shown to be an extradural arteriovenous fistula according to the histopathological examination.
CONCLUSIONS: In atypical MRI findings of the spine, vascular malformations should be considered. In cases with a spinal dural arteriovenous fistula, the thrombosis risk can be high and lead to a need for prolonged anticoagulation.

Spinal extradural arachnoid cysts are rare benign lesions occurring along the cerebrospinal axis. They may be associated with pain or varying degrees of neurological compressive symptoms. Brown-Sequard syndrome is a rare sequalae, where there is ipsilateral upper motor neuron paralysis with loss of proprioception as well as contralateral loss of pain and temperature sensation below the lesion. We present a 33-year-old female with a 6-month history of worsening right lower limb weakness and a 2-month history of right lower limb pain. Motor examination revealed right lower limb weakness as well as exaggerated knee and ankle jerk reflexes. A magnetic resonance imaging (MRI) was done, which showed an eccentrically located T4-7 cystic extradural mass causing severe cord compression. She had T4-7 laminectomies with total excision of the cyst and disconnection of the fistulous tract between the cyst and the subarachnoid space. She made full neurologic recovery with no complications.

Spinal Ewing\'s Sarcoma is a rare tumour predominantly affecting children and adolescents. We describe the case of an 18-year-old male patient who first presented with a primary extradural cervical Ewing\'s sarcoma tumour, and 5 years later had a recurrence with thoracolumbar and lumbosacral intradural extramedullary Ewing\'s sarcoma tumours. Both presentations were successfully treated by surgical resection and adjuvant chemo- and radiotherapy, and he remains disease-free at 12 months follow-up. This is the first reported case of seeding of tumour from an extradural primary Ewing\'s sarcoma to intradural metastases. Total surgical resection of his initial cervical tumour, performed at another centre, was complicated by a dural tear and CSF leak. Thus, we propose that isolated drop metastasis via CSF fistula is the most likely mechanism for tumour spread in this case. Thus, clinicians may wish to counsel patients on the possibility of such spread if a CSF leak is encountered, and potentially increase the frequency of imaging surveillance of the whole spine in this context.

Hydatidosis is a parasitic infestation whose etiological agent is the larva of the cestode Echinococcus granulosus. It is a zoonosis, and the human being behaves as an accidental intermediate host in the parasitic cycle with pediatric predominance. The most frequent clinical presentation is hepatic, followed by pulmonary, with cerebral hydatidosis being extremely rare. Imaging is characteristic, generally dealing with single cystic lesion, usually unilocular and less frequently multilocular, located mainly intraaxially. Extradural hydatid cyst, whether primary or secondary, remains very rare or even exceptional. The primary disease remains extremely rare, and its clinical picture is related to the number, size, and location of the lesions. Infection within these cerebral hydatid cysts remains an extremely rare occurrence, and only few cases were reported previously in the literature. The authors report the nosological review of the clinical, imaging, surgical, and histopathological records of a pediatric primary osteolytic extradural and complicated hydatid cyst in a 5-year-old North African male patient coming from a rural area who presented for progressive onset of a painless left parieto-occipital soft swelling without any neurological disorder with good outcomes after surgery. The authors report this case due the fact that it had not been documented before in the pediatric population and to the success of the specialized treatment.

UNASSIGNED: Meningiomas are mostly benign and slow-growing neoplasms of the central nervous system. Spinal meningiomas account for up to 45% of all intradural spinal tumors in adults and up to 25%-45% of all spinal tumors. Spinal extradural meningiomas are rare and may be easily confused with malignant neoplasms.
UNASSIGNED: A 24-year-old woman was presented to our hospital with paraplegia and loss of sensation in the T7 dermatome and lower body. MRI findings showed T6-T7 right-sided intradural extramedullary and extradural lesion, measuring 1.4 cm × 1.5 cm × 3 cm, extending to the right foramen, compressing the spinal cord, and displacing it to the left. Hyperintense lesion on T2 and hypointense lesion on T1 were observed. The patient reported improvement after surgery and during follow-up. We recommend maximizing the decompression during surgery to achieve better clinical outcome. Extradural meningiomas represent 5% of all meningiomas; therefore, having an intradural on top of extradural meningioma with extraforaminal extensions makes this a unique and rare case.
UNASSIGNED: Meningiomas can be easily missed in diagnosis depending on imaging and the pathognomonic pattern it represents, which can mimic other pathologies, such as schwannomas. Therefore, surgeons should always suspect their patient having a meningioma even if the pattern is not typical. Moreover, preoperative preparation, such as navigation and defect closure, must be taken in case it turns out be a meningioma instead of the presumed pathology.

Meningiomas are the most common central nervous system tumor. They are typically benign neoplasms but may produce neurological symptoms due to mass effect. Meningiomas may also extend to extradural locations; however, these account for only a small percentage of all meningiomas. Most extradural meningiomas arise in intraosseous locations, usually within the cranial bones or vertebrae. However, this is a rare case of extradural extension of an asymptomatic intracranial meningioma to the proximal humerus in the absence of any musculoskeletal symptoms. To the best of our knowledge, this presentation of an extradural intraosseous meningioma has not previously been reported in the literature. We present a case of an incidental intraosseous meningioma in a 66-year-old man. This patient was initially being screened for metastasis of stage IA1 adenocarcinoma of the lung, and a positron emission tomography (PET) scan revealed a focus of activity in the proximal diaphysis of the right humerus suspicious for malignancy. The upper extremity magnetic resonance imaging (MRI) demonstrated an indeterminate lesion. Curettage of the humeral lesion revealed an intraosseous psammomatous meningioma without evidence of metastatic lung carcinoma. Our case report aims to illustrate the importance of considering alternative metastatic sources, such as intracranial meningioma, during the investigation of an indeterminate bony lesion. This is the first case to illustrate asymptomatic intraosseous meningioma in an appendicular skeletal location, highlighting the need for thorough source investigation.