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Benjamin K. Hendricks, Aaron A. Cohen-Gadol and James C. Miller

Glioblastoma (GBM) is the most common primary brain tumor and carries a grave prognosis. Despite years of research investigating potentially new therapies for GBM, the median survival rate of individuals with this disease has remained fairly stagnant. Delivery of drugs to the tumor site is hampered by various barriers posed by the GBM pathological process and by the complex physiology of the blood-brain and blood–cerebrospinal fluid barriers. These anatomical and physiological barriers serve as a natural protection for the brain and preserve brain homeostasis, but they also have significantly limited the reach of intraparenchymal treatments in patients with GBM.

In this article, the authors review the functional capabilities of the physical and physiological barriers that impede chemotherapy for GBM, with a specific focus on the pathological alterations of the blood-brain barrier (BBB) in this disease. They also provide an overview of current and future methods for circumventing these barriers in therapeutic interventions. Although ongoing research has yielded some potential options for future GBM therapies, delivery of chemotherapy medications across the BBB remains elusive and has limited the efficacy of these medications.

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Benjamin K. Hendricks and Aaron A. Cohen-Gadol

Epidermoid cysts or tumors comprise 1% of intracranial tumors with a predilection for the cerebellopontine angle or parasellar cisterns. These tumors are derived from an ectopic ectodermal implant seeded between fusing ectodermal surfaces. This results in a benign proliferation of stratified squamous epithelium along a cyst wall with a lumen composed of hyperkeratotic material derived from the desquamating cells. Surgical intervention is the treatment of choice for symptomatic patients. There is no role for radiotherapy or chemotherapy in the treatment of these lesions, including for residual or recurrent disease. The inherent adhesion of the proliferating epithelial lining to surrounding neurovascular structures significantly complicates attempts at gross-total resection. Epidermoid tumors or cysts are rarely reported within the third ventricular region. In this video, the authors demonstrate the technique of right-sided posterior interhemispheric transcallosal approach for maximal resection of a complex recurrent third ventricular epidermoid tumor with lateral ventricular extension.

The video can be found here: https://youtu.be/wbXp7mc0vT4.

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Todd J. Wannemuehler, Kolin E. Rubel, Benjamin K. Hendricks, Jonathan Y. Ting, Troy D. Payner, Mitesh V. Shah and Aaron A. Cohen-Gadol

OBJECTIVE

Craniopharyngiomas have historically been resected via transcranial microsurgery (TCM). In the last 2 decades, the extended endoscopic endonasal (transtuberculum) approach to these tumors has become more widely accepted, yet there remains controversy over which approach leads to better outcomes. The purpose of this study is to determine whether differences in outcomes were identified between TCM and extended endoscopic endonasal approaches (EEEAs) in adult patients undergoing primary resection of suprasellar craniopharyngiomas at a single institution.

METHODS

A retrospective review of all patients who underwent resection of their histopathologically confirmed craniopharyngiomas at the authors' institution between 2005 and 2015 was performed. Pediatric patients, revision cases, and patients with tumors greater than 2 standard deviations above the mean volume were excluded. The patients were divided into 2 groups: those undergoing primary TCM and those undergoing a primary EEEA. Preoperative patient demographics, presenting symptoms, and preoperative tumor volumes were determined. Extent of resection, tumor histological subtype, postoperative complications, and additional outcome data were obtained. Statistical significance between variables was determined utilizing Student t-tests, chi-square tests, and Fisher exact tests when applicable.

RESULTS

After exclusions, 21 patients satisfied the aforementioned inclusion criteria; 12 underwent TCM for resection while 9 benefitted from the EEEA. There were no significant differences in patient demographics, presenting symptoms, tumor subtype, or preoperative tumor volumes; no tumors had significant lateral or prechiasmatic extension. The extent of resection was similar between these 2 groups, as was the necessity for additional surgery or adjuvant therapy. CSF leakage was encountered only in the EEEA group (2 patients). Importantly, the rate of postoperative visual improvement was significantly higher in the EEEA group than in the TCM group (88.9% vs 25.0%; p = 0.0075). Postoperative visual deterioration only occurred in the TCM group (3 patients). Recurrence was uncommon, with similar rates between the groups. Other complication rates, overall complication risk, and additional outcome measures were similar between these groups as well.

CONCLUSIONS

Based on this study, most outcome variables appear to be similar between TCM and EEEA routes for similarly sized tumors in adults. The multidisciplinary EEEA to craniopharyngioma resection represents a safe and compelling alternative to TCM. The authors' data demonstrate that postoperative visual improvement is statistically more likely in the EEEA despite the increased risk of CSF leakage. These results add to the growing evidence that the EEEA may be considered the approach of choice for resection of select confined primary craniopharyngiomas without significant lateral extension in centers with experienced surgeons. Further prospective, multiinstitutional collaboration is needed to power studies capable of fully evaluating indications and appropriate approaches for craniopharyngiomas.

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Mahdi Malekpour, Charles Kulwin, Bradley N. Bohnstedt, Golnar Radmand, Rishabh Sethia, Stephen K. Mendenhall, Jonathan Weyhenmeyer, Benjamin K. Hendricks, Thomas Leipzig, Troy D. Payner, Mitesh V. Shah, John Scott, Andrew DeNardo, Daniel Sahlein and Aaron A. Cohen-Gadol

OBJECTIVE

Aneurysmal rebleeding before definitive obliteration of the aneurysm is a cause of mortality and morbidity. There are limited data on the role of short-term antifibrinolytic therapy among patients undergoing endovascular intervention.

METHODS

All consecutive patients receiving endovascular therapy for their ruptured saccular aneurysm at the authors' institution between 2000 and 2011 were included in this study. These patients underwent endovascular coiling of their aneurysm within 72 hours of admission. In patients receiving ε-aminocaproic acid (EACA), the EACA administration was continued until the time of the endovascular procedure. Complications and clinical outcomes of endovascular treatment after aneurysmal subarachnoid hemorrhage (aSAH) were compared between EACA-treated and untreated patients.

RESULTS

During the 12-year study period, 341 patients underwent endovascular coiling. Short-term EACA treatment was administered in 146 patients and was withheld in the other 195 patients. EACA treatment did not change the risk of preinterventional rebleeding in this study (OR 0.782, 95% CI 0.176–3.480; p = 0.747). Moreover, EACA treatment did not increase the rate of thromboembolic events. On the other hand, patients who received EACA treatment had a significantly longer duration of hospital stay compared with their counterparts who were not treated with EACA (median 19 days, interquartile range [IQR] 12.5–30 days vs median 14 days, IQR 10–23 days; p < 0.001). EACA treatment was associated with increased odds of shunt requirement (OR 2.047, 95% CI 1.043–4.018; p = 0.037) and decreased odds of developing cardiac complications (OR 0.138, 95% CI 0.031–0.604; p = 0.009) and respiratory insufficiency (OR 0.471, 95% CI 0.239–0.926; p = 0.029). Short-term EACA treatment did not affect the Glasgow Outcome Scale score at discharge, 6 months, or 1 year following discharge.

CONCLUSIONS

In this study, short-term EACA treatment in patients who suffered from aSAH and received endovascular aneurysm repair did not decrease the risk of preinterventional rebleeding or increase the risk of thrombotic events. EACA did not affect outcome. Randomized clinical trials are required to provide robust clinical recommendation on short-term use of EACA.

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Benjamin K. Hendricks, James S. Yoon, Kurt Yaeger, Christopher P. Kellner, J Mocco, Reade A. De Leacy, Andrew F. Ducruet, Michael T. Lawton and Justin R. Mascitelli

OBJECTIVE

Wide-necked aneurysms (WNAs) are a variably defined subset of cerebral aneurysms that require more advanced endovascular and microsurgical techniques than those required for narrow-necked aneurysms. The neurosurgical literature includes many definitions of WNAs, and a systematic review has not been performed to identify the most commonly used or optimal definition. The purpose of this systematic review was to highlight the most commonly used definition of WNAs.

METHODS

The authors searched PubMed for the years 1998–2017, using the terms “wide neck aneurysm” and “broad neck aneurysm” to identify relevant articles. All results were screened for having a minimum of 30 patients and for clearly stating a definition of WNA. Reference lists for all articles meeting the inclusion criteria were also screened for eligibility.

RESULTS

The search of the neurosurgical literature identified 809 records, of which 686 were excluded (626 with < 30 patients; 60 for lack of a WNA definition), leaving 123 articles for analysis. Twenty-seven unique definitions were identified and condensed into 14 definitions. The most common definition was neck size ≥ 4 mm or dome-to-neck ratio < 2, which was used in 49 articles (39.8%). The second most commonly used definition was neck size ≥ 4 mm, which was used in 26 articles (21.1%). The rest of the definitions included similar parameters with variable thresholds. There was inconsistent reporting of the precise dome measurements used to determine the dome-to-neck ratio. Digital subtraction angiography was the only imaging modality used to study the aneurysm morphology in 87 of 122 articles (71.3%).

CONCLUSIONS

The literature has great variability regarding the definition of a WNA. The most prevalent definition is a neck diameter of ≥ 4 mm or a dome-to-neck ratio of < 2. Whether this is the most appropriate and clinically useful definition is an area for future study.

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Visish M. Srinivasan, Aditya Srivatsan, Alejandro M. Spiotta, Benjamin K. Hendricks, Andrew F. Ducruet, Felipe C. Albuquerque, Ajit Puri, Matthew R. Amans, Steven W. Hetts, Daniel L. Cooke, Christopher S. Ogilvy, Ajith J. Thomas, Alejandro Enriquez-Marulanda, Ansaar Rai, SoHyun Boo, Andrew P. Carlson, R. Webster Crowley, Leonardo Rangel-Castilla, Giuseppe Lanzino, Peng Roc Chen, Orlando Diaz, Bradley N. Bohnstedt, Kyle P. O’Connor, Jan-Karl Burkhardt, Jeremiah N. Johnson, Stephen R. Chen and Peter Kan

OBJECTIVE

Traditionally, stent-assisted coiling and balloon remodeling have been the primary endovascular treatments for wide-necked intracranial aneurysms with complex morphologies. PulseRider is an aneurysm neck reconstruction device that provides parent vessel protection for aneurysm coiling. The objective of this study was to report early postmarket results with the PulseRider device.

METHODS

This study was a prospective registry of patients treated with PulseRider at 13 American neurointerventional centers following FDA approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and perioperative events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications.

RESULTS

A total of 54 aneurysms were treated, with the same number of PulseRider devices, across 13 centers. Fourteen cases were in off-label locations (7 anterior communicating artery, 6 middle cerebral artery, and 1 A1 segment anterior cerebral artery aneurysms). The average dome/neck ratio was 1.2. Technical success was achieved in 52 cases (96.2%). Major complications included the following: 3 procedure-related posterior cerebral artery strokes, a device-related intraoperative aneurysm rupture, and a delayed device thrombosis. Immediately postoperative Raymond-Roy occlusion classification (RROC) class 1 was achieved in 21 cases (40.3%), class 2 in 15 (28.8%), and class 3 in 16 cases (30.7%). Additional devices were used in 3 aneurysms. For those patients with 3- or 6-month angiographic follow-up (28 patients), 18 aneurysms (64.2%) were RROC class 1 and 8 (28.5%) were RROC class 2.

CONCLUSIONS

PulseRider is being used in both on- and off-label cases following FDA approval. The clinical and radiographic outcomes are comparable in real-world experience to the outcomes observed in earlier studies. Further experience is needed with the device to determine its role in the neurointerventionalist’s armamentarium, especially with regard to its off-label use.