Sentinel report of uniquely paired collision tumors: glioblastoma multiforme and coexistent intraventricular subependymoma. Illustrative case.

BACKGROUND: The presence of intracranial collision tumors, histologically distinct tumors occurring in anatomical proximity, is quite rare. Herein, the authors describe the sentinel case of a contiguous collision tumor combination consisting of glioblastoma multiforme and intraventricular subependymoma. OBSERVATIONS: A 67-year-old male presented with several months of progressive fatigue superimposed on more recently noted word-finding difficulty, slight left-sided weakness, and episodic confusion. He was found to have a large right frontal mass abutting the right lateral ventricle with an additional nodular focus of enhancement within the right frontal horn. The patient underwent an awake right frontal craniotomy for gross-total resection of the tumor, noted to be of two distinct histological identities. LESSONS: Although exceptionally rare, primary glial neoplasms of various histologies can be encountered simultaneously during resection, as in this case of co-occurring glioblastoma of the right frontal lobe and right frontal horn intraventricular subependymoma. Close attention to tumoral locations and the gross appearance of specimens during resection can prime the operative neurosurgeon for success in contributing to accurate diagnoses through sending separate pathological specimens for histological analysis when qualitatively different tissue is suspected.

Great Hospitals: The History of Neurosurgery at the University of Vermont Medical Center-A Macroscopic Examination of Microscope-Savvy Pioneers.

The University of Vermont's (UVM) Division of Neurosurgery is enshrined in a rich history of innovation and academic prowess, which have significantly contributed to making neurosurgery the field it is today. From humble beginnings, the department was started by one Raymond Madiford Peardon "Pete" Donaghy on a parenthetically watertight research budget amounting to $25 and shared space in a Quonset hut. Passion and commitment to progress, as well as an innate openness to collaboration, propelled Pete Donaghy, his colleagues, pupils, and successors to establish an exemplary center for treatment of neurosurgical disease, with multiple revolutionary accomplishments along the way. These accomplishments include the birth and promotion of microneurosurgery, the performance of the first extracranial to intracranial bypass, and the education of other neurosurgical giants. The New England Skull Base Course, held annually in UVM's "R.M. Peardon Donaghy Microvascular and Skull Base Laboratory," is a 3-day cadaver-based teaching course for neurosurgery and ear nose and throat residents throughout New England. The course bears testament to Donaghy's everlasting influence on the UVM Division of Neurosurgery and continues to positively affect the education of countless trainees. The purpose of this historical perspective is to outline the events and accomplishments that define the UVM Division of Neurosurgery's many contributions to the field at large and the ongoing efforts to honor Donaghy's example through maintaining a culture of humility, hard work, and commitment to neurosurgical innovation and education.

Surgical removal of a compressive thoracic epidural vascular malformation in a patient with Klippel-Trénaunay syndrome: illustrative case.

BACKGROUND: Klippel-Trénaunay syndrome (KTS) is a combined capillary-lymphatic-venous malformation disorder traditionally associated with high surgical morbidity. Although rare, pathologic involvement of the spinal cord has been reported in the literature. However, the safety of surgical intervention remains unclear. We report a case of successful decompression of a thoracic epidural lesion in an individual with KTS who presented with spastic paraparesis. OBSERVATIONS: The patient is a 38-year-old male, diagnosed with KTS as an infant, who presented with spastic paraparesis secondary to a thoracic epidural lesion. He underwent laminectomies and resection of the lesion with subsequent improvement of his symptoms and without significant postoperative morbidity. Histopathology confirmed the lesion to be a benign vascular malformation. LESSONS: Currently, the literature regarding management of symptomatic vascular lesions in individuals with KTS supports nonoperative management, due to the increased risk of operative morbidity associated with this syndrome. This case presents evidence for safe and appropriate surgical management of a thoracic epidural vascular malformation in a patient with KTS in the setting of progressive neurological decline, establishing a role for neurosurgical intervention in this high-risk population when no conservative management portends further neurological deterioration.

Aneurysm presence at the anterior communicating artery bifurcation is associated with caliber tapering of the A1 segment.

OBJECTIVE: Vessel tapering results in blood flow acceleration at downstream bifurcations (firehose nozzle effect), induces hemodynamics predisposing to aneurysm initiation, and has been associated with middle cerebral artery (MCA) aneurysm presence and rupture status. The authors sought to determine if vessel caliber tapering is a generalizable predisposing factor by evaluating upstream A1 segment profiles in association with aneurysm presence in the anterior communicating artery (ACoA) complex, the most prevalent cerebral aneurysm location associated with a high rupture risk. METHODS: Three-dimensional rotational angiographic studies were analyzed for 68 patients with ACoA aneurysms, 37 nonaneurysmal contralaterals, and 53 healthy bilateral controls (211 samples total). A1 segments were determined to be dominant, codominant, or nondominant based on flow and size. Equidistant cross-sectional orthogonal cuts were generated along the A1 centerline, and cross-sectional area (CSA) was evaluated proximally and distally, using intensity-invariant edge detection filtering. The relative tapering of the A1 segment was evaluated as the tapering ratio (distal/proximal CSA). Computational fluid dynamics was simulated on ACoA parametric models with and without tapering. RESULTS: Aneurysms occurred predominantly on dominant (79%) and codominant (17%) A1 segments. A1 segments leading to unruptured ACoA aneurysms had significantly greater tapering compared to nonaneurysmal contralaterals (0.69 ± 0.13 vs 0.80 ± 0.17, p = 0.001) and healthy controls (0.69 ± 0.13 vs 0.83 ± 0.16, p < 0.001), regardless of dominance labeling. There was no statistically significant difference in tapering values between contralateral A1 and healthy A1 controls (0.80 ± 0.17 vs 0.83 ± 0.16, p = 0.56). Hemodynamically, A1 segment tapering induces high focal pressure, high wall shear stress, and high velocity at the ACoA bifurcation. CONCLUSIONS: Aneurysmal, but not contralateral or healthy control, A1 segments demonstrated significant progressive vascular tapering, which is associated with aneurysmogenic hemodynamic conditions at the ACoA complex. Demonstration of the upstream tapering effect in the communicating ACoA segment is consistent with its prior detection in the noncommunicating MCA bifurcation, which together form more than 50% of intracranial aneurysms. The mechanistic characterization of this upstream vascular tapering phenomenon is warranted to understand its clinical relevance and devise potential therapeutic strategies.

Bilateral Thalamic Glioma: A Case Report.

Bilateral thalamic primary gliomas are an exceedingly rare entity. Symptomology heralding a workup and diagnosis of bithalamic gliomas is diverse and varies between the pediatric and adult populations. Herein, we present a case of a 63-year-old female patient who presented with progressive gait imbalance and fatigue, prompting an outpatient brain MRI, remarkable for marked expansion of the bilateral thalami secondary to non-enhancing, T2-weighted-fluid-attenuated inversion recovery (T2-FLAIR) bright bithalamic lesions. The patient underwent a right frontal frameless stereotactic biopsy of the right thalamic lesion, with immuno-histology indicating a high-grade anaplastic astrocytoma with molecular features of glioblastoma (GBM). The patient's functional status declined precipitously in the month following her diagnostic biopsy, precluding any therapy, and the patient ultimately pursued home hospice care without further treatment. This case details the clinical management of a very rare tumor, supplementing the available literature on the progression and treatment of this rare disease.

Urothelial cell carcinoma presenting with rapid visual deterioration, a case of rare brain metastases with unique clinical presentation.

BACKGROUND: Urothelial cell carcinoma (UCC), the most common cancer of the urinary system, rarely metastasizes to the brain. 1-3 More rare still is the subset of patients with urothelial carcinoma brain metastases whose UCC primary is first diagnosed at the same time as their CNS metastatic disease, with oncologic workup prompted by CNS clinical manifestations.4 Paraneoplastic optic neuropathy (PON) is likewise a rare clinical entity, which has not yet been described in association with UCC brain metastases. CASE DESCRIPTION: Herein, we present the sentinel case of UCC believed to be of endometrial origin in an 81 year old woman initially presenting with symptoms of fatigue, nausea, vertigo, and rapidly deteriorating vision over the course of 1 month. Visual deterioration prompted neuro imaging remarkable for multiple supratentorial and infratentorial metastases as well as likely neoplastic inflammatory involvement of the bilateral optic nerves. The patient underwent a right temporal open brain biopsy, with pathology findings consistent with UCC. Subsequent PET scanning demonstrated a heavy burden of disease including an FDG-avid uterine mass with local and distal extension of disease including bilateral hydroureteronephrosis with obstruction of the distal ureters. The patient and her family elected to pursue home hospice without further workup or intervention. CONCLUSIONS: While this is the first such case presented, it is possible that UCC of the uterine wall represents a particularly aggressive form of the disease more prone to presenting with CNS metastases and PON.

Endoscopic supracerebellar infratentorial approach to pineal region epidermoid tumor.

Epidermoid cysts of the pineal region are a rare entity. Herein, the authors describe the endoscopic resection of a recurrent pineal region epidermoid by way of a supracerebellar infratentorial approach. The patient was positioned in the semiseated upright position with head tilted to the right and slightly flexed, maximizing gravity-based cerebellar retraction, and a paramedian craniotomy was performed owing to the gradual flattening of the tentorium from medial to lateral. This setup, in tandem with the enlarged viewing window achieved by use of 0°, 30°, and 70° endoscopes, afforded the necessary access to achieve a satisfactory resection through this anatomical corridor. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2131.

Half of Unplanned Readmissions Following One or Two-Level Anterior Cervical Decompression and Fusion Are Unrelated to Surgical Site.

MINI: In this study we analyze rates of readmission, and the timing and reasons for readmission after one to two level anterior cervical decompression and fusion. Among 18,833 patients who underwent anterior cervical decompression and fusion, 3% were readmitted to the hospital within 30 days. 39.5% of readmissions were for reasons related to surgical site. STUDY DESIGN: Retrospective review of a national database. OBJECTIVE: In this study we analyze rates of readmission, and the timing and reasons for readmission after one to two level anterior cervical decompression and fusion (ACDF). SUMMARY OF BACKGROUND DATA: The safety profile of ACDF has been previously described with readmission rates typically between 2% and 4%. However no studies have investigated the primary diagnoses driving readmission, and whether these diagnoses are related to the surgical site. METHODS: Demographics, comorbidities, and procedural characteristics were collected for all patients undergoing one or two-level ACDF for degenerative indications identified by Current Procedural Terminology (CPT) coding in the National Surgical Quality Improvement Program (NSQIP) database. The incidence of 30-day complications and readmissions was calculated, and the reasons for readmission as well as the timing of readmission were reviewed. Multivariate logistic regression analyses were performed to identify risk factors associated with complications or readmissions within 30 days of surgery. RESULTS: Eighteen thousand eight hundred thirty three patients underwent ACDF (15,464 single-level and 3369 two-level, mean age 53.7 yrs, standard deviation [SD]: 11.6; 50% male). Postoperative complication rate of was 4.3% in two-level fusions and 3.5% in single-level fusion (P = 0.027). Five hundred sixty nine unplanned readmissions were identified (3.0%), of which 39.5% were related to the surgical site and 49.7% were unrelated to the surgical site (10.5% unknown cause of readmission). The most frequent reason for 30-day readmission was pneumonia (9.3%, mean time to readmission of 11.3 d) followed by dysphagia (7.4%, 6.3 d), and acute postoperative pain (7.2%, 11.4 d). CONCLUSION: In this nationwide analysis of 18,833 ACDF cases, 3.0% of patients were readmitted within 30 days, of which at least 49.7% were for reasons unrelated to the surgical site. LEVEL OF EVIDENCE: 3.

Retrospective review of a national database. In this study we analyze rates of readmission, and the timing and reasons for readmission after one to two level anterior cervical decompression and fusion (ACDF). The safety profile of ACDF has been previously described with readmission rates typically between 2% and 4%. However no studies have investigated the primary diagnoses driving readmission, and whether these diagnoses are related to the surgical site. Demographics, comorbidities, and procedural characteristics were collected for all patients undergoing one or two-level ACDF for degenerative indications identified by Current Procedural Terminology (CPT) coding in the National Surgical Quality Improvement Program (NSQIP) database. The incidence of 30-day complications and readmissions was calculated, and the reasons for readmission as well as the timing of readmission were reviewed. Multivariate logistic regression analyses were performed to identify risk factors associated with complications or readmissions within 30 days of surgery. Eighteen thousand eight hundred thirty three patients underwent ACDF (15,464 single-level and 3369 two-level, mean age 53.7 yrs, standard deviation [SD]: 11.6; 50% male). Postoperative complication rate of was 4.3% in two-level fusions and 3.5% in single-level fusion (P = 0.027). Five hundred sixty nine unplanned readmissions were identified (3.0%), of which 39.5% were related to the surgical site and 49.7% were unrelated to the surgical site (10.5% unknown cause of readmission). The most frequent reason for 30-day readmission was pneumonia (9.3%, mean time to readmission of 11.3 d) followed by dysphagia (7.4%, 6.3 d), and acute postoperative pain (7.2%, 11.4 d). In this nationwide analysis of 18,833 ACDF cases, 3.0% of patients were readmitted within 30 days, of which at least 49.7% were for reasons unrelated to the surgical site. Level of Evidence: 3.

Disseminated Rosette-Forming Glioneuronal Tumor with Spinal Drop Metastasis, a Uniquely Aggressive Presentation of Rare Tumor.

BACKGROUND: The rosette-forming glioneuronal tumor (RGNT) is a rare World Health Organization grade I tumor, most often originating in the fourth ventricle and characterized by a predominant glial component, as well as a neurocytic component. Despite its benign grading, there are a few documented cases of RGNT displaying more aggressive behavior with malignant characteristics. CASE DESCRIPTION: Herein, we describe a uniquely aggressive presentation of RGNT in a 49-year-old man initially presenting with obstructive hydrocephalus with lesions in the right frontal lobe, fourth ventricle, and left lateral ventricle. The patient was found to have 2 distinct intracranial entities: a right frontal meningioma and disseminated intraventricular RGNT. He underwent an anatomically limited resection of the fourth ventricular lesion with fourth ventricle-to-subarachnoid space shunting. His disease progressed thereafter, with diffuse intracranial dissemination and drop metastases in the lumbar spine. He was treated with craniospinal radiation and remains on palliative care 5 months after completion of radiotherapy. CONCLUSIONS: This case supplements and complements the handful of published cases available documenting the evolution of a particularly aggressive case of disseminated RGNT.

Flow diversion for treatment of intracranial aneurysms: Mechanism and implications.

Flow diverters are new generation stents that have recently garnered a large amount of interest for use in treatment of intracranial aneurysms. Flow diverters reduce blood flow into the aneurysm, with redirection along the path of the parent vessel. Flow stagnation into the aneurysm and neck coverage with subsequent endothelialization are the important synergistic mechanisms by which the therapy acts. Several studies have examined the mechanisms by which flow diverters subsequently lead to aneurysm occlusion. This review aims to provide a general overview of the flow diverters and their mechanism of action and potential implications. ANN NEUROL 2019;85:793-800.