BACKGROUND: Aneurysmal bone cysts (ABCs) are rare, highly vascular osteolytic bone lesions that predominantly affect pediatric populations. This report evaluates the clinicopathological data of pediatric patients with spinal ABCs. The medical records for all patients at Children\'s Hospital Los Angeles with biopsy-proven ABCs of the spine between 1998 and 2018 were evaluated.
METHODS: Seventeen patients, 6 males and 11 females, were identified. The mean age at surgery was 10.4 years (range, 3.5-20 years). The most common presenting complaint was pain at the lesion site 16/17 (94%), followed by lower-extremity weakness 8/17 (47%). Resection and intralesional curettage were performed in all patients. Three (18%) of 17 patients underwent selective arterial embolization prior to resection. Spinal stability was compromised in 15 of 17 patients (88%), requiring instrumented fusion. Five (29%) of the 17 patients received additional therapy including radiation, calcitonin-methylprednisolone, or phenol. Four (23.5%) of 17 patients experienced a recurrence, and the mean time to recurrence was 15 months. The postoperative follow-up ranged from 6 to 108 months (median, 28 months). Reoperation occurred after an average of 35 months. At the recent follow-up, patients were free of disease.
CONCLUSIONS: Gross-total resection by intralesional curettage with case-dependent instrumented spinal fusion for instability remains an effective strategy for managing pediatric spinal ABCs. Long-term follow-up is necessary to detect tumor recurrence.

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.
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.
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.

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.
METHODS: 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.
CONCLUSIONS: 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.

BACKGROUND: The authors report a case of a 66-year-old male who presented acutely with a subdural hematoma who was managed operatively with craniotomy. His course was complicated by a postoperative epidural hematoma, which, on the basis of intraoperative findings at the second surgery, was managed with evacuation of the hematoma and removal of the bone flap.
METHODS: The patient\'s subsequent recovery was remarkable for a reproducible positional aphasia in the early postoperative period with an ultimate diagnosis of syndrome of the trephined. The patient\'s cerebral edema permitted early autologous cranioplasty, which resulted in resolution of the patient\'s symptoms.
CONCLUSIONS: The authors believe this case to be the first described of isolated positional aphasia as a manifestation of syndrome of the trephined. Recognition and treatment of the syndrome resulted in a positive patient outcome.

BACKGROUND: The authors\' previous cadaveric study reported a new surgical approach that can expose the deep cerebellar hemisphere, cerebellopontine angle, and upper fourth ventricle through dissection of the horizontal fissure of the suboccipital cerebellar hemisphere. Here, the authors present their experience with the first clinical use of the suboccipital trans-horizontal fissure (SOTHF) approach requiring access to the third and upper fourth ventricle lesions, a challenging compartment to access by traditional approaches.
METHODS: In cases 1 and 2, computed tomography demonstrated large hematomas in the left cerebellar hemisphere with extension into the third ventricle and/or the upper fourth ventricle, resulting in obstructive hydrocephalus. Large hematomas in both the cerebellar hemisphere and the upper fourth ventricle were successfully removed via an SOTHF approach alone without external ventricular drainage. Furthermore, the hematoma in the third ventricle was removed through the aqueduct in case 2. Access to the upper fourth ventricle and the third ventricle were intraoperatively verified using a neuronavigation system. The patients immediately regained consciousness, and the result of cerebellar function testing was almost normal after the operation.
CONCLUSIONS: An SOTHF approach can achieve the removal of cerebellar and intraventricular hematomas simultaneously, is a faster and potentially safer method than others, and subsequently allows rapid clinical improvement.

BACKGROUND: A three-column osteotomy results in dural buckling, which may appear concerning upon intraoperative visualization because it may appear that the neural elements may also be buckled. The authors presented an intraoperative view after intentional durotomy of the neural elements and the relaxed state of the dura after three-column osteotomy.
METHODS: A 52-year-old woman with adult tethered cord syndrome and previous untethering presented with worsening leg pain and stiffness, urinary incontinence, and unbalanced gait. Magnetic resonance imaging demonstrated an arachnoid web at T6 and spinal cord tethering. Spinal column shortening via three-column osteotomy was performed with concomitant intradural excision of the arachnoid web. Dural buckling was observed intraoperatively after spinal column shortening. After the durotomy, the spinal cord was visualized without kinking or buckling.
CONCLUSIONS: Dural buckling after spinal column shortening of 15 mm via three-column osteotomy at T6 did not result in concomitant buckling of the underlying neural elements.

BACKGROUND: Trapping an aneurysm after the establishment of an extracranial to intracranial high-flow bypass is considered the optimal surgical strategy for ruptured blood blister-like aneurysms (BBAs) of the internal carotid artery (ICA). For high-flow bypass surgeries, a radial artery graft is generally preferred over a saphenous vein graft (SVG). However, SVGs can be advantageous in acute-phase surgeries because of their greater length, easy manipulability, ability to act as high-flow conduits, and reduced risk of vasospasms. In this study, the authors presented five cases of ruptured BBAs treated with high-flow bypass using an SVG followed by BBA trapping, and they reported on surgical outcomes and operative nuances that may help avoid potential pitfalls.
METHODS: After the surgeries, there were no ischemic or hemorrhagic complications, including symptomatic vasospasms. In three of the five cases, postoperative modified Rankin scale scores were between 0 and 2 at the 3-month follow-up. In one case, the SVG spontaneously occluded after surgery while the protective superficial temporal artery (STA) to middle cerebral artery (MCA) bypass became dominant, and the patient experienced no ischemic symptoms.
CONCLUSIONS: High-flow bypass using an SVG with a protective STA-MCA bypass followed by BBA trapping is a safe and effective treatment strategy.

BACKGROUND: Central nervous system (CNS) tuberculomas are a feared complication of tuberculosis (TB) infection. These lesions can present in varying manners and are associated with significant morbidity and mortality. Prompt diagnosis and treatment of the lesion and the underlying infection are critical in the care of these patients. The authors presented a case of a 45-year-old Yemeni immigrant presenting with a 3-month history of severe right temporo-occipital headaches with photophobia and night sweats. Imaging showed a rim-enhancing lesion in the right cerebellar hemisphere.
METHODS: Laboratory tests were unremarkable and within normal limits. QuantiFERON testing was negative, ruling out latent TB infection. The patient received a suboccipital craniotomy, and resection of the cerebellar lesion showed caseating granuloma formation, which was positive for acid-fast bacilli and Fite stain.
CONCLUSIONS: CNS tuberculomas are an important differential to consider in patients with a history of primary TB, regardless of active disease or immunocompetent status. Resection of these lesions remains a viable treatment option that is safe and effective.

BACKGROUND: Anatomical variations, such as high jugular bulbs and air cell development in the petrosal bone, should be evaluated before surgery. Most bone defects in the internal auditory canal (IAC) posterior wall are observed in the perilabyrinthine cells. An aberrant vascular structure passing through the petrous bone is rare.
METHODS: A 48-year-old man presented with a right ear hearing disturbance. Magnetic resonance imaging revealed a 23-mm contrast-enhancing mass in the right cerebellopontine angle extending into the IAC, consistent with a right vestibular schwannoma. Preoperative bone window computed tomographic scans showed bone defects in the IAC posterior wall, which ran farther posteroinferiorly in the petrous bone, reaching the medial part of the jugular bulb. The tumor was accessed via a lateral suboccipital approach. There was no other major vein in the cerebellomedullary cistern, except for the vein running from the brain stem to the IAC posterior wall. To avoid complications due to venous congestion, the authors did not drill out the IAC posterior wall or remove the tumor in the IAC.
CONCLUSIONS: Several aberrant veins in the petrous bone are primitive head sinus remnants. Although rare, their surgical implication is critical in patients with vestibular schwannomas.

BACKGROUND: Xanthoma is a granulomatous lesion that develops from leakage of circulating serum lipoprotein into the surrounding tissue. An isolated intracranial xanthoma is rarely reported and usually misdiagnosed. Intracranial xanthoma is also rarely found in patients with hyperlipidemia. To the best of the authors\' knowledge, no previous studies and literature have reported bilateral involvement of intracranial xanthoma in the frontal lobe.
METHODS: The authors reported an unusual case of bilateral involvement of intracranial xanthoma in the frontal lobe with associated type II hyperlipidemia in a 42-year-old woman. Macroscopically, the tumor had an appearance of greyish-yellow color with a brittle, solid consistency. Histopathological examination revealed numerous lipid-laden macrophages surrounded by a cystic, necrotic, partially hemorrhagic area, with some parts consisting of hemosiderophages and proliferative capillary blood vessels. The histopathological findings indicated the characteristics of xanthoma.
CONCLUSIONS: Bilateral frontal intracranial xanthoma with associated type II hyperlipidemia is an unusual finding. Despite its rarity and wide variety of radiological presentations, it should be considered one of the differential diagnoses of lesions that develop intracranially and intraaxially. Confirmation with histopathological examination is needed to exclude from other differential diagnoses.