Papillary glioneuronal tumor presenting with low-pressure hydrocephalus from intraventricular spread: Case Report.

Papillary glioneuronal tumors are a rare and typically benign entity with pathological and radiographic complexity. Presentation can mimic other neoplasms, making diagnosis more challenging. The literature to date describes the clinical understanding, diagnostic, therapeutic, and prognostic characteristics of this limited number of patients. In this article, we report an unusual case of a glioneuronal tumor with multifocal presentation, normal pressure hydrocephalus-like symptoms, and large peritumoral parenchymal cysts, which guided the surgical approach. This unusual presentation has not previously been reported and adds valuable information to the clinical recognition and management literature.

The Use of a Pipeline Embolization Device for Treatment of a Ruptured Dissecting Middle Cerebral Artery M3/M4 Aneurysm: Challenges and Technical Considerations.

Prompt, effective treatment is necessary following aneurysmal subarachnoid hemorrhage to prevent recurrent rupture, which is thought to double mortality. Atypical ruptured aneurysms, such as blister or dissecting pseudoaneurysms, or those that are unusually distal in the middle cerebral artery (MCA) are challenging to treat with either open or endovascular options, though the pipeline embolization device (PED) has shown promise in multiple case series. We present a case of a ruptured dissecting pseudoaneurysm in the distal MCA (distal M3/proximal M4) prefrontal division in an healthy young patient (<60 years) successfully treated with a PED. The PED was chosen both as the only vessel sparing option in the young patient as well as for its potential as a vessel sacrifice tool if the pseudoaneurysm was felt to be incompletely treated, which in this case was not necessary-though would have leveraged the thrombogenicity of the device as a therapeutic advantage.

Recurrent Primary Intrasellar Paraganglioma.

We describe a case of an 81-year-old male presenting with bitemporal visual field defects and blurry vision in the right eye. The patient was found to have a recurrent primary paraganglioma in the sellar and suprasellar region requiring a repeat transsphenoidal endoscopic resection. Immunohistochemical examination confirmed paraganglioma with the classic zellballen appearance which stained positive for chromogranin, synaptophysin, and S-100 in the periphery. Paragangliomas (PGLs) in the sella turcica are a rare entity; only 19 cases have ever been reported in the literature. PGLs in the sellar region are often misdiagnosed or diagnosed in a delayed fashion. Earlier diagnosis of this locally aggressive tumor and meticulous debulking can prevent morbidity secondary to the tumor's compressive effects. This report highlights the effectiveness of surgical interventions in treatment of paragangliomas. More research is still needed to determine the need for adjuvant therapies such as radiation.

Denosumab Treatment for a Residual Giant Cell Tumor of the Clivus: A Case Report and Review of the Literature.

BACKGROUND: Giant cell tumors (GCTs) are a locally aggressive primary bone neoplasm of osteoclast-like cells. These lesions largely occur in the epiphyses of long bones, but there have been rare reports of occurrence in the pelvis, spine, or skull. Of those located in the skull, involvement of the clivus has been rarely reported. CASE DESCRIPTION: We present a case of an 18-year-old woman presenting with a third nerve palsy, found to have a lytic lesion of the upper clivus that was primarily treated with endoscopic endonasal resection. Her third nerve palsy resolved postoperatively, and subsequent histopathologic analysis revealed a GCT. Six-month postoperative magnetic resonance imaging (MRI) revealed progression of residual disease for which she was treated with adjuvant denosumab. This treatment resulted in a significant decrease in the tumor size. She subsequently underwent proton beam radiation. At 1-year postsurgery, the patient's MRI remained stable after completing denosumab and proton therapy. She was neurologically intact and had no issues from her treatment. CONCLUSIONS: Denosumab has demonstrated anti-GCT efficacy. In combination with proton therapy, it has the potential to spare a young, vulnerable population from adverse long-term effects of traditional adjuvant radiation therapy. To our knowledge, this is the first report of the use of denosumab in the treatment of GCT of the clivus in the United States.

Intraoperative angiography via the popliteal artery: a useful technique for patients in the prone position.

OBJECTIVE Intraoperative angiography can be a valuable tool in the surgical management of vascular disorders in the CNS. This is typically accomplished via femoral artery puncture; however, this can be technically difficult in patients in the prone position. The authors describe the feasibility of intraoperative angiography via the popliteal artery in the prone patient. METHODS Three patients underwent intraoperative spinal angiography in the prone position via vascular access through the popliteal artery. Standard angiography techniques were used, along with ultrasound and a micropuncture needle for initial vascular access. Two patients underwent intraoperative angiography to confirm the obliteration of dural arteriovenous fistulas. The third patient required unexpected intraoperative angiography when a tumor was concerning for a vascular malformation in the cervical spine. RESULTS All 3 patients tolerated the procedure without complication. The popliteal artery was easily accessed without any adaptation to typical patient positioning for these prone-position cases. This proved particularly beneficial when angiography was not part of the preoperative plan. CONCLUSIONS Intraoperative angiography via the popliteal artery is feasible and well tolerated. It presents significant benefit when obtaining imaging studies in patients in a prone position, with the added benefit of easy access, familiar anatomy, and low concern for catheter thrombosis or kinking.

Neurosurgical Management of Self-Inflicted Cranial Crossbow Injury.

BACKGROUND: Although gun-related penetrating traumatic brain injuries make up the majority of cranial missile injuries, low-velocity penetrating injuries present significant clinical difficulties that cannot necessarily be identically managed. Bow hunting is an increasingly popular pastime, and a crossbow allows a unique mechanism to cause a self-inflicted cranial injury with a large, low-velocity projectile. Historically, arrow removal is described in an operating room setting, which provides limited knowledge of the location of vascular injury in the setting of postremoval hemorrhage, and may represent an inefficient use of operating room availability. CASE DESCRIPTION: Two patients presented after self-inflicted cranial crossbow injuries. Both were neurologically salvageable. Initial assessment with computed tomography angiography allowed triage into likely or unlikely vascular injury. Arrow removal was performed in a radiology setting rather than in the operating room to allow immediate postremoval imaging to localize hemorrhage. While an operating room was on standby, neither patient required neurosurgical operative intervention. Both patients made a good recovery with no further injury caused by arrow removal. CONCLUSIONS: We describe a novel approach to retained cranial arrow removal in a radiologic, rather than operative, setting and describe its relative benefits over traditional removal in the operating room.

Pediatric Pontine Cavernous Malformations: The Presigmoid, Posterior Petrosal Approach.

BACKGROUND: Brainstem cavernous malformations (cavernomas) in children have a high risk of hemorrhage and neurological deterioration. This risk is magnified if the child has a genetic predisposition for cavernoma formation. The surgical management is challenging and carries a significant risk of morbidity. OBJECTIVE: To describe the feasibility of a posterior petrosal approach to brainstem cavernomas in a pediatric population. METHODS: A single institution operative experience with this technique was reviewed; 2 cases were identified and are technically described here with supportive figures and illustrations, as well as a focused literature review. RESULTS: Two pediatric cases with multiple symptomatic hemorrhages from large expanding pontine cavernomas were identified. Both cavernomas were resected through a presigmoid posterior petrosal approach. While this approach is well described in the adult literature for ventral brainstem lesions, its description for the treatment of pontine cavernomas in the pediatric populations is scarce. CONCLUSION: This study demonstrates the utility and feasibility of the posterior petrosal approach in two pediatric patients at different points in cranial base development.

Technology that achieves the Triple Aim: an economic analysis of the BrainPath™ approach in neurosurgery.

BACKGROUND: The Triple Aim is defined as: improving the patient experience of care, improving the health of populations, and reducing the per capita cost of health care. The purpose of this analysis was to evaluate the economic value of a new neurosurgical technique, the BrainPath™ approach, for use in patients with subcortical tumors and intracerebral hemorrhage (ICH). METHODS: Inpatient length of stay (LOS) data were collected for ICH and brain tumor surgical patient cases between August 2013 and November 2015. Patient cases were separated into two groups; BrainPath approach (n = 28) and conventional techniques, such as craniotomy, (n = 208). The average intensive care unit (ICU) LOS was calculated for each group by diagnosis-related group and compared between groups. RESULTS: The new surgical technology resulted in surgical intervention in 14 ICH cases which otherwise would have been medically managed due to the hemorrhage location or size of the ICH. A reduction in ICU LOS was seen in this group. Based on the variable direct cost per day in the neuro critical care unit at this academic medical center, 14 patient cases incurred ~ US$210,000 less in direct ICU costs. Surgical resection was possible in two tumor patient cases which would have been biopsied, rather than surgically resected, also due to location of the abnormalities. A total net value of > US$329,000 is attributable to the analyzed approach over a 28-month period. CONCLUSION: This analysis shows positive economic value for the new technology group when ICU LOS and reimbursement are considered against equipment costs, thus achieving Triple Aim objectives.

Minimally Invasive Transsulcal Resection of Intraventricular and Periventricular Lesions Through a Tubular Retractor System: Multicentric Experience and Results.

BACKGROUND: Conventional approaches to deep-seated cerebral lesions range from biopsy to transcortical or transcallosal resection. Although the former does not reduce tumor burden, the latter are more invasive and associated with greater potential for irreparable injury to normal brain. Disconnection syndrome, hemiparesis, hemianesthesia, or aphasia is not uncommon after such surgery, especially when lesion is large. By contrast, the transsulcal parafascicular approach uses naturally existing corridors and a tubular retractor to minimize brain injury. METHODS: A retrospective review of patients undergoing minimally invasive transsulcal parafascicular resection of ventricular and periventricular lesions, across 5 independent centers, was conducted. RESULTS: Twenty patients with lesions located in the lateral ventricle (n = 9), the third ventricle (n = 6) and periventricular region (n = 4) are described in this report. Average age was 64 years (8 male/12 female). The average depth from cortical surface was 4.37 cm. A 13.5-mm-diameter tubular retractor (BrainPath [NICO Corporation, Indianapolis, Indiana, USA]) of differing lengths was used, aided by neuronavigation. Gross total resection was obtained in 17 patients. Pathologies included colloid cyst, subependymoma, glioma, meningioma, central neurocytoma, lymphoma, and metastasis. Three patients experienced transient morbidity: memory loss (2), hemiparesis (1). One patient died 3 months postoperatively as a result of unrelated pulmonary illness. Follow-up ranged from 6 to 27 months (average, 12 months). CONCLUSIONS: This technique is safe and effective for the treatment of intraventricular and periventricular lesions. Surgery-related morbidity is minimal and often transient. Lesions are satisfactorily resected and residuum occurs only when the neoplasm involves vital structures. The tubular retractor minimizes trauma to brain incident in the surgeon's path.

Posterior interhemispheric transfalcine transprecuneus approach for microsurgical resection of periatrial lesions: indications, technique, and outcomes.

OBJECT: Surgical exposure of the peritrigonal or periatrial region has been challenging due to the depth of the region and overlying important functional cortices and white matter tracts. The authors demonstrate the operative feasibility of a contralateral posterior interhemispheric transfalcine transprecuneus approach (PITTA) to this region and present a series of patients treated via this operative route. METHODS: Fourteen consecutive patients underwent the PITTA and were included in this study. Pre- and postoperative clinical and radiological data points were retrospectively collected. Complications and extent of resection were reviewed. RESULTS: The mean age of patients at the time of surgery was 39 years (range 11-64 years). Six of the 14 patients were female. The mean duration of follow-up was 4.6 months (range 0.5-19.6 months). Pathology included 6 arteriovenous malformations, 4 gliomas, 2 meningiomas, 1 metastatic lesion, and 1 gray matter heterotopia. Based on the results shown on postoperative MRI, 1 lesion (7%) was intentionally subtotally resected, but ≥ 95% resection was achieved in all others (93%) and gross-total resection was accomplished in 7 (54%) of 13. One patient (7%) experienced a temporary approach-related complication. At last follow-up, 1 patient (7%) had died due to complications of his underlying malignancy unrelated to his cranial surgery, 2 (14%) demonstrated a Glasgow Outcome Scale (GOS) score of 4, and 11 (79%) manifested a GOS score of 5. CONCLUSIONS: Based on this patient series, the contralateral PITTA potentially offers numerous advantages, including a wider, safer operative corridor, minimal need for ipsilateral brain manipulation, and better intraoperative navigation and working angles.

Analysis of the tortuosity of the internal carotid artery in the cavernous sinus.

BACKGROUND: The morphology of the internal carotid artery at the skull base is important in radiologic interpretation, surgery, and more recently, endovascular interventional and diagnostic procedures. Therefore, a thorough knowledge of the shape of the carotid siphon can be important in the clinical realm. METHODS: In this study, we evaluated the shape of the carotid siphon from a lateral perspective on cerebral angiography. These shapes were then correlated to the Lang and Reiter classification. RESULTS: Types A, B, and C were distributed as follows: type A 12 (30%), B 16 (40%), 12 (30%). There was no significant difference (p > 0.05) in patient ages between the three types (type A 54.6 ± 14.2 years, type B 55.1 ± 14.9 years, and type C 52.7 ± 16.9 years). Normalized for gender disproportion, there was no significant gender predominance for any type (type A female:male = 1.4:1; type B female:male = 1.1:1; type C female:male = 0.7:1). CONCLUSIONS: Such a classification scheme with additional application in another group might be of use to future studies aimed at the morphology of the cavernous part of the internal carotid artery.

Radiographic and clinical outcome of syringomyelia in patients treated for tethered cord syndrome without other significant imaging abnormalities.

OBJECT: The surgical management of patients with symptoms of tethered cord syndrome (TCS) who lack significant radiographic abnormalities is controversial. One potential MRI marker for TCS is a spinal cord syrinx or syringomyelia. Alternatively, a syrinx may be a benign and incidental finding. In this report the authors evaluated a highly selected cohort of patients with symptoms of TCS with minimal radiographic abnormalities other than syringomyelia. They analyzed clinical and radiographic outcomes after tethered cord release (TCR). METHODS: A retrospective review of data from 16 children who met the study inclusion criteria was performed. All patients had been surgically treated at Riley Hospital for Children in Indianapolis, Indiana, between 2006 and 2011. All children had clinical symptoms of TCS as well as available pre- and postoperative MRI data. RESULTS: The most common presentation (12 [75%] of 16 patients) was urinary dysfunction, defined as symptoms of urgency or incontinence with abnormal urodynamic studies. Clinical follow-up data were available in 11 of these 12 patients. All 11 had improvement in symptoms at an average follow-up of 17 months. Seven (87.5%) of 8 patients presenting with back or leg pain had improvement. Three patients had progressive scoliosis; 2 had stabilization of the curve or mild improvement, and 1 patient had worsening deformity. Radiographic follow-up data were obtained an average of 14.5 months after surgery. Twelve patients (75%) had stable syringomyelia after TCR. Four patients showed improvement, with 2 having complete radiographic resolution. CONCLUSIONS: Highly selected patients with symptoms of TCS did very well clinically. Patients with abnormal urodynamic studies, pain, and gait disturbances showed a high rate of symptomatic improvement. However, a smaller percentage of patients had radiographic improvement of the syrinx. Therefore, the authors suggest that the decision to perform TCR should be based on clinical symptoms in this population. Symptomatic improvement was not necessarily related to radiographic resolution of the syrinx.

Outcomes for clip ligation and hematoma evacuation associated with 102 patients with ruptured middle cerebral artery aneurysms.

OBJECTIVE: Few studies have investigated the implications of intracerebral hematoma (ICH) due to rupture of a middle cerebral artery (MCA) aneurysm and patient outcomes. We hypothesized that patients with Hunt-Hess (HH) grade IV-V may not benefit from aggressive measures. METHODS: A prospectively acquired aneurysm database was examined. We found 144 patients who harbored a ruptured MCA aneurysm and suffered from ICH or intrasylvian hematoma with or without subarachnoid hemorrhage. The mean age of our patients was 52.5 years (range, 10-82 years) with 87 women and 57 men. Of these, 122 (84.7%) underwent a combination of interventions, including clip ligation, hematoma evacuation, and/or endosaccular coiling; most patients underwent clip ligation at the same time as their hematoma was evacuated. The discharge information was not available for two patients. We examined significant associations among presenting details (e.g., age, sex, admission HH grade) and patients' final outcome. RESULTS: The total in-hospital mortality rate was 49% (70 of 142 patients); 42% (51 of 120) for the patients who underwent an intervention and 86.4% (19 of 22) for those who did not undergo any intervention. Among our patients, approximately 52% with an admission HH grade of IV/V died in-hospital after surgery, whereas 21% with admission HH grade of I-III expired during the same time. In the patient cohort with presenting with HH grade IV and V, 4% (3 of 76) demonstrated Glasgow outcome scale 4-5 at discharge, whereas 15% (12 of 78) displayed Glasgow outcome scale 4-5 at 6-month follow-up. Age and sex did not affect outcome. CONCLUSIONS: Aggressive clip ligation and hematoma evacuation remains a reasonable option for patients suffering from an ICH associated with a ruptured MCA aneurysm. Admission HH grade is the primary prognostic factor for outcome among this patient population as more than half of patients with HH grade IV and V expired during their hospitalization despite aggressive treatment of their hematoma and aneurysm. Long-term functional outcome was poor in up to 85% of surviving patients with HH grade IV-V. It may be beneficial to discuss these prognostic factors with the family before implementing aggressive measures.

Technical nuances of resection of giant (> 5 cm) vestibular schwannomas: pearls for success.

Removal of vestibular schwannomas (VSs, or acoustic neuromas) remains one of the most challenging operations in neurosurgery. Giant or huge tumors (> 5 cm) heighten these challenges, and technical nuances play a special role in maximizing tumor resection while minimizing complications. In this article, the senior author describes his technical experience with microsurgical excision of giant VSs. The accompanying video further illustrates these details.

Temporal and optic pathway pilomyxoid astrocytoma mimicking dural-based lesion: case report and review of the literature.

Pilomyxoid astrocytomas (PMAs) are low-grade tumors that share many common traits with pilocytic astrocytomas. However, PMAs have a more worrisome clinical course, with a higher recurrence rate, lower survival rate, and higher risk of leptomeningeal spread compared to pilocytic tumors. These tumors tend to occur in younger children and are typically located in the area of the optic chiasm or hypothalamus. There are few studies examining the radiographic appearance of these lesions. In this case report, the authors present an unusual radiographic appearance of a PMA in an 11-year-old child. Preoperative images suggested a dural-based, homogenously enhancing lesion coupled with an enlarged optic nerve. Surgery revealed an intraparenchymal lesion of the right temporal lobe. There was hyperintensity on T2 MRI sequences, suggesting infiltration of the tumor along the optic tracts.

Tumor bleeding from a de novo aneurysm associated with optic glioma.

Aneurysms in children are rare and potentially devastating lesions. The authors report the case of a 16-year-old girl with a complicated medical history related to a chiasmal glioma diagnosed at 18 months of age. She had previously received multiple modalities of radiation treatment, including external beam, proton therapy, and Gamma Knife. She presented with hemorrhage centered in the tumor and extending into the ventricular space. There was no subarachnoid blood. Magnetic resonance imaging demonstrated the hemorrhage and tumor anatomy. Magnetic resonance angiography revealed an aneurysm at the internal carotid artery bifurcation, but the lesion was more clearly delineated on CT angiography. A comparison MR imaging study obtained 6 months earlier, even in retrospect, did not show evidence of an aneurysm. This case illustrates the salient point that the clinician must search for vascular lesions in the patient with spontaneous "tumor bleeding," especially if that patient has risk factors for aneurysm formation. The authors also suggest that a CT angiogram is better at radiographically demonstrating an intratumoral aneurysm than an MR angiogram in this scenario.