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1.
J Neurooncol ; 161(3): 617-623, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36745272

ABSTRACT

PURPOSE: Operative guidelines and use optimization for new surgical exoscopes are not well described in the literature. In this study, we evaluated use of the ORBEYE (Olympus) surgical exoscope system during 5-ALA fluorescence-guided resection of GBMs to optimize workflow and exoscope settings. METHODS: The ORBEYE exoscope system was fitted with a blue light filter for 5-ALA mediated fluorescence-guided surgery (FGS). Intraoperative images were obtained during 5-ALA FGS in 9 patients with primary or recurrent GBM. The exoscope was set up at constant, increasing focal distances from the target tissue, and light source intensity varied. High-resolution 4 K images were captured and analyzed. Comparisons of fluorescence to background were then generated for use optimization. RESULTS: Light intensity did not significantly influence tumor fluorescence (P = 0.878). However, focal distance significantly impacted relative fluorescent intensity (P = 0.007). Maximum average fluorescence was seen consistently at a focal length of 220 mm and a light intensity of approximately 75% maximum. Decreasing focal distance from 400 mm to 220 mm significantly increased visualized fluorescence (P = 0.0038). CONCLUSIONS: The ORBEYE surgical exoscope system with blue light filter is a powerful imaging tool for 5-ALA FGS in GBM. The ORBEYE blue filter performs optimally at shorter focal distance with moderate light intensity. Similar to microscope systems, decreasing focal distance significantly influences visualized fluorescence.


Subject(s)
Brain Neoplasms , Glioblastoma , Surgery, Computer-Assisted , Humans , Glioblastoma/diagnostic imaging , Glioblastoma/surgery , Glioblastoma/pathology , Fluorescence , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/surgery , Brain Neoplasms/pathology , Surgery, Computer-Assisted/methods , Aminolevulinic Acid , Neurosurgical Procedures
2.
J Neurooncol ; 161(1): 127-133, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36629962

ABSTRACT

PURPOSE: Iatrogenic neurologic deficits adversely affect patient outcomes following brain tumor resection. Motor evoked potential (MEP) monitoring allows surgeons to assess the integrity of motor-eloquent areas in real-time during tumor resection to lessen the risk of iatrogenic insult. We retrospectively associate intraoperative transcranial and direct cortical MEPs (TC-MEPs, DC-MEPs) to early and late post-operative motor function to prognosticate short- and long-term motor recovery in brain tumor patients undergoing surgical resection in peri-eloquent regions. METHODS: We reviewed 121 brain tumor patients undergoing craniotomies with DC-MEP and/or TC-MEP monitoring. Motor function scores were recorded at multiple time-points up to 1 year postoperatively. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated at each time point. RESULTS: The sensitivity, specificity, PPV, and NPV of TC-MEP in the immediate postoperative period was 17.5%, 100%, 100%, and 69.4%, respectively. For DC-MEP monitoring, the respective values were 25.0%, 100%, 100%, and 68.8%. By discharge, sensitivity had increased for both TC-MEP and DC MEPs to 43.8%, and 50.0% respectively. Subset analysis on patients without tumor recurrence/progression at long term follow-up (n = 62 pts, 51.2%) found that all patients with stable monitoring maintained or improved from preoperative status. One patient with transient intraoperative TC-MEP loss and permanent DC-MEP loss suffered a permanent deficit. CONCLUSION: Brain tumor patients who undergo surgery with intact MEP monitoring and experience new postoperative deficits likely suffer transient deficits that will improve over the postoperative course in the absence of disease progression.


Subject(s)
Brain Neoplasms , Evoked Potentials, Motor , Humans , Evoked Potentials, Motor/physiology , Prognosis , Retrospective Studies , Neoplasm Recurrence, Local , Brain Neoplasms/surgery , Iatrogenic Disease
3.
J Neurooncol ; 163(3): 485-503, 2023 Jul.
Article in English | MEDLINE | ID: mdl-37354356

ABSTRACT

PURPOSE: We systematically reviewed visual outcomes over the last three decades in patients undergoing treatment for base of skull (BOS) meningiomas and provide recommendations to preserve vision. METHODS: In accordance with the PRISMA guidelines for systematic reviews, a search was conducted from 6/1/2022-9/1/2022 using PubMed and Web of Science. Inclusion criteria included (1) patients treated for BOS meningiomas (2) treatment modality specified (3) specifics of surgical techniques and/or dose/fractions of radiotherapy (4) individual patient outcomes of treatment. Each study was assessed for bias based on study design and heterogeneity of results. RESULTS: A total of 50 studies were included (N = 2911). When comparing improved vision versus unchanged or worsened vision, studies investigating surgery alone published from 2006 and onward had significantly better visual outcomes compared to pre-2006 studies (p = 0.02). When comparing improved vision versus unchanged or worsened vision, studies investigating combined therapy with surgery and radiation published from 2008 and onward had significantly better visual outcomes compared to pre-2008 studies (p < 0.01). Combined modality therapy was less likely to worsen vision compared to either surgery or radiation monotherapy (p < 0.01). However, surgery and radiation monotherapy were more likely to actually improve outcomes compared to combination therapy (p < 0.01). CONCLUSION: For over a decade we have observed improvement in visual outcomes in patients managed for meningioma of BOS, likely attributing the innovation in microsurgical and more targeted and conformal radiation techniques. Combination therapy may be the safest option for preventing worsening of vision, but the highest rates of improving visual function are achieved through monotherapy when indicated.


Subject(s)
Meningeal Neoplasms , Meningioma , Humans , Meningioma/radiotherapy , Meningioma/surgery , Treatment Outcome , Retrospective Studies , Skull Base/surgery , Meningeal Neoplasms/radiotherapy , Meningeal Neoplasms/surgery
4.
J Neurooncol ; 159(2): 369-375, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35764906

ABSTRACT

OBJECTIVE: Stimulated Raman histology (SRH) offers efficient and accurate intraoperative neuropathological tissue analysis without procedural alteration to the diagnostic specimen. However, there are limited data demonstrating one-to-one tissue comparisons between SRH and traditional frozen sectioning. This study explores the non-inferiority of SRH as compared to frozen section on the same piece of tissue in neurosurgical patients. METHODS: Tissue was collected over a 1-month period from 18 patients who underwent resection of central nervous system lesions. SRH and frozen section analyses were compared for diagnostic capabilities as well as assessed for quality and condition of tissue via a survey completed by pathologists. RESULTS: SRH was sufficient for diagnosis in 78% of specimens as compared to 94% of specimens by frozen section of the same specimen. A Fisher's exact test determined there was no significant difference in diagnostic capability between the two groups. Additionally, both quality of SRH and condition of tissue after SRH were deemed to be non-inferior to frozen section. CONCLUSIONS: This study provides further evidence for the non-inferiority of SRH techniques. It is also the first study to demonstrate SRH accuracy using one-to-one tissue analysis in neuropathological specimens.


Subject(s)
Frozen Sections , Humans
5.
Acta Neurochir (Wien) ; 164(5): 1255-1263, 2022 05.
Article in English | MEDLINE | ID: mdl-35233664

ABSTRACT

BACKGROUND: Temporary clipping is an important tool in the vascular neurosurgeon's armamentarium. We routinely utilize intraoperative neurophysiological monitoring (IONM) for complex brain aneurysm surgery cases, relying on direct cortical motor evoked potential (DCMEP) alerts to guide the duration of temporary clipping. Previous studies have argued for relatively short and intermittent temporary clipping strategies. In this study, we sought to assess the maximal permissive temporary clipping time during complex aneurysm surgery. To do this, we assessed patient outcome in relation to temporary clip duration guided by DCMEP. METHODS: We queried our prospectively collected neuromonitoring database for anterior circulation aneurysm cases where temporary clipping was utilized by a single cerebrovascular surgeon between 2018 and 2021. Operative and IONM reports were reviewed. Patients in whom the duration of temporary clipping could not be determined were excluded. The operative strategy permissively allowed continuous temporary clipping as long as no neuromonitoring alerts were encountered. Maximal permissive parent artery occlusion time (Clipmax) was recorded as the longest duration of tolerated temporary vessel clipping without decrement in DCMEP. RESULTS: A total of 41 complex anterior circulation aneurysm clipping cases met criteria for this study. The mean Clipmax for all cases was just over 19 min and did not differ between ruptured and unruptured aneurysms. Initial alert times were not found to be predictive of final permissive temporary clip duration after re-perfusion. In 100% (41/41) of cases, the aneurysm was completely clip occluded without residual on catheter angiogram. Stable or improved modified Rankin Score was achieved in 98% (40/41) of cases at 3-month follow-up. CONCLUSIONS: This study demonstrates that using DCMEP can facilitate relatively long but safe temporary clipping durations in complex anterior circulation aneurysm surgery. In the endovascular era with only a limited subset of technically challenging aneurysms needing open surgical treatment, extended permissive temporary clipping guided by DCMEPs can significantly enhance a surgeon's ability to achieve excellent technical and clinical outcomes.


Subject(s)
Intracranial Aneurysm , Intraoperative Neurophysiological Monitoring , Evoked Potentials, Motor/physiology , Humans , Intracranial Aneurysm/diagnostic imaging , Intracranial Aneurysm/surgery , Neurosurgical Procedures , Vascular Surgical Procedures
6.
Br J Neurosurg ; : 1-6, 2021 Oct 05.
Article in English | MEDLINE | ID: mdl-34608831

ABSTRACT

PURPOSE: Carotid endarterectomy (CEA) is effective in treating carotid artery stenosis to prevent stroke. Historically, this operation has been performed utilizing loupe magnification with or without the operating microscope (OM). However, there remains a need for continued improvement in operative visualization and surgical ergonomics. Recently, newly developed digital 'exoscope' has provided the surgeon with unique lighting and magnification as well as improvements in surgical ergonomics and working angle. We sought to review our cumulative experience using a novel 4K high-definition (4K-HD) 3-dimensional (3D) exoscope (EX) for CEA surgery. METHODS: All CEA surgery cases at our institution between 2013 and 2019 using the 4K-HD 3D EX were reviewed. Operative parameters, patient outcome and operator's assessment of the EX compared to OM-assisted cases was conducted. RESULTS: 28 patients were treated, 10 of which were operated using the EX. All procedures were performed without perioperative complications, or significant differences in operative parameters (blood loss <20 cm3 and 164 ± 49.5 minutes) compared to OM-assisted cases. Operators reported improved level of comfort performing 'high' bifurcation surgery and improved visualization and posture during inspection of the distal ICA lumen as primary advantages of EX-assisted CEA over OM-assisted CEA. CONCLUSIONS: The ORBEYE EX, albeit a learning curve necessitating a short period of the OR team, provided safety and outcome comparable to OM-assisted surgery. Potential advantages noted were improved visualization and ergonomics specifically for when extreme working angles were required. Our experience suggests that the exoscope may become a valuable alternative to standard magnification tools in CEA surgery.

7.
J Neurooncol ; 147(2): 279, 2020 04.
Article in English | MEDLINE | ID: mdl-32170632

ABSTRACT

The name of author Jason A. Ellis was missing in the intial online publication, and there was a typo in the sixth author's first name. The original article has been corrected.

8.
J Neurooncol ; 147(2): 261-278, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32076934

ABSTRACT

INTRODUCTION: Intra-arterial (IA) delivery of therapeutic agents across the blood-brain barrier (BBB) is an evolving strategy which enables the distribution of high concentration therapeutics through a targeted vascular territory, while potentially limiting systemic toxicity. Studies have demonstrated IA methods to be safe and efficacious for a variety of therapeutics. However, further characterization of the clinical efficacy of IA therapy for the treatment of brain tumors and refinement of its potential applications are necessary. METHODS: We have reviewed the preclinical and clinical evidence supporting superselective intraarterial cerebral infusion (SSIACI) with BBB disruption for the treatment of brain tumors. In addition, we review ongoing clinical trials expanding the applicability and investigating the efficacy of IA therapy for the treatment of brain tumors. RESULTS: Trends in recent studies have embraced the use of SSIACI and less neurotoxic chemotherapies. The majority of trials continue to use mannitol as the preferred method of hyperosmolar BBB disruption. Recent preclinical and preliminary human investigations into the IA delivery of Bevacizumab have demonstrated its safety and efficacy as an anti-tumor agent both alone and in combination with chemotherapy. CONCLUSION: IA drug delivery may significantly affect the way treatments are delivered to patients with brain tumors, and in particular GBM. With refinement and standardization of the techniques of IA drug delivery, improved drug selection and formulations, and the development of methods to minimize treatment-related neurological injury, IA therapy may offer significant benefits for the treatment of brain tumors.


Subject(s)
Antineoplastic Agents/administration & dosage , Blood-Brain Barrier/drug effects , Brain Neoplasms/drug therapy , Drug Delivery Systems , Infusions, Intra-Arterial/methods , Neoplasm Recurrence, Local/prevention & control , Animals , Humans , Treatment Outcome
10.
J Neurooncol ; 135(3): 497-506, 2017 Dec.
Article in English | MEDLINE | ID: mdl-28875440

ABSTRACT

Computational modeling shows that intra-arterial delivery is most efficient when the delivered drugs rapidly and avidly bind to the target site. The cell-penetrating peptide trans-activator of transcription (TAT) is a candidate carrier molecule that could mediate such specificity for brain tumor chemotherapeutics. To test this hypothesis we first performed in vitro studies testing the uptake of TAT by one primary and three potentially metastatic brain cancer cell lines (9L, 4T-1, LLC, SKOV-3). Then we performed in vivo studies in a rat model where TAT was delivered either intra-arterially (IA) or intravenously (IV) to 9L brain tumors. We observed robust uptake of TAT by all tumor cell lines in vitro. Flow cytometry and confocal microscopy revealed a rapid uptake of fluorescein-labeled TAT within 5 min of exposure to the cancer cells. IA injections done under transient cerebral hypoperfusion (TCH) generated a four-fold greater tumor TAT concentration compared to conventional IV injections. We conclude that it is feasible to selectively target brain tumors with TAT-linked chemotherapy by the IA-TCH method.


Subject(s)
Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , Cell-Penetrating Peptides/administration & dosage , Drug Delivery Systems , Gene Products, tat/administration & dosage , Glioma/drug therapy , Administration, Intravenous , Animals , Brain/drug effects , Brain/metabolism , Brain/pathology , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Cell Line, Tumor , Drug Delivery Systems/methods , Glioma/metabolism , Glioma/pathology , Humans , Injections, Intra-Arterial , Mice , Neoplasm Transplantation , Rats, Inbred F344
11.
J Neurooncol ; 133(1): 77-85, 2017 05.
Article in English | MEDLINE | ID: mdl-28421460

ABSTRACT

The cell-penetrating trans-activator of transcription (TAT) is a cationic peptide derived from human immunodeficiency virus-1. It has been used to facilitate macromolecule delivery to various cell types. This cationic peptide is capable of crossing the blood-brain barrier and therefore might be useful for enhancing the delivery of drugs that target brain tumors. Here we test the efficiency with which relatively small (20 nm) micelles can be delivered by an intra-arterial route specifically to gliomas. Utilizing the well-established method of flow-arrest intra-arterial injection we compared the degree of brain tumor deposition of cationic TAT-decorated micelles versus neutral micelles. Our in vivo and post-mortem analyses confirm glioma-specific deposition of both TAT-decorated and neutral micelles. Increased tumor deposition conferred by the positive charge on the TAT-decorated micelles was modest. Computational modeling suggested a decreased relevance of particle charge at the small sizes tested but not for larger particles. We conclude that continued optimization of micelles may represent a viable strategy for targeting brain tumors after intra-arterial injection. Particle size and charge are important to consider during the directed development of nanoparticles for intra-arterial delivery to brain tumors.


Subject(s)
Brain Neoplasms/drug therapy , Drug Delivery Systems , Gene Products, tat , Glioma/drug therapy , Micelles , Animals , Blood-Brain Barrier/drug effects , Blood-Brain Barrier/metabolism , Brain Neoplasms/metabolism , Cations , Cell Line, Tumor , Computer Simulation , Dose-Response Relationship, Drug , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Gene Products, tat/chemistry , Glioma/metabolism , Hemodynamics , Hydrogen-Ion Concentration , Injections, Intra-Arterial , Models, Biological , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Particle Size , Rats
12.
J Neurooncol ; 128(1): 21-28, 2016 05.
Article in English | MEDLINE | ID: mdl-26903015

ABSTRACT

The relative abundance of anionic lipids on the surface of endothelia and on glioma cells suggests a workable strategy for selective drug delivery by utilizing cationic nanoparticles. Furthermore, the extracellular pH of gliomas is relatively acidic suggesting that tumor selectivity could be further enhanced if nanoparticles can be designed to cationize in such an environment. With these motivating hypotheses the objective of this study was to determine whether nanoparticulate (20 nm) micelles could be designed to improve their deposition within gliomas in an animal model. To test this, we performed intra-arterial injection of micelles labeled with an optically quantifiable dye. We observed significantly greater deposition (end-tissue concentration) of cationizable micelles as compared to non-ionizable micelles in the ipsilateral hemisphere of normal brains. More importantly, we noted enhanced deposition of cationizable as compared to non-ionizable micelles in glioma tissue as judged by semiquantitative fluorescence analysis. Micelles were generally able to penetrate to the core of the gliomas tested. Thus we conclude that cationizable micelles may be constructed as vehicles for facilitating glioma-selective delivery of compounds after intraarterial injection.


Subject(s)
Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , Drug Delivery Systems , Glioma/drug therapy , Micelles , Animals , Brain/diagnostic imaging , Brain/drug effects , Brain/metabolism , Brain Neoplasms/diagnostic imaging , Brain Neoplasms/metabolism , Cations/metabolism , Fluorescent Dyes , Glioma/diagnostic imaging , Glioma/metabolism , Injections, Intra-Arterial , Neoplasm Transplantation , Optical Imaging , Polyethylene Glycols , Rats, Inbred F344 , Rats, Sprague-Dawley , Spectrum Analysis
13.
J Neurooncol ; 130(3): 449-454, 2016 12.
Article in English | MEDLINE | ID: mdl-27576697

ABSTRACT

Mitoxantrone is a highly cytotoxic antineoplastic drug, however, its poor penetration of the blood-brain barrier has limited its role in the treatment of brain cancers. We hypothesize that intra-arterial (IA) delivery of mitoxantrone may enhance its capacity for regional brain deposition thus expanding its potential as a brain tumor therapy agent. In this study we assessed the dose-response characteristics as well as the feasibility and safety of mitoxantrone delivery to the brain and specifically to gliomas in a rodent model. We show that delivery optimization utilizing the technique of intra-arterial transient cerebral hypoperfusion (IA-TCH) facilitates achieving the highest peak- and end- brain drug concentrations as compared to intravenous and IA delivery without hypoperfusion. Additionally, we observed significant tumor-specific uptake of mitoxantrone when delivered by the IA-TCH method. No untoward effects of IA-TCH delivery of mitoxantrone were observed. The IA-TCH method is shown to be a safely tolerated and feasible strategy for delivering mitoxantrone to tumors in the glioma model tested. Additional investigation is warranted to determine if IA-TCH delivery of mitoxantrone produces clinically relevant benefit.


Subject(s)
Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , Glioma/drug therapy , Mitoxantrone/administration & dosage , Animals , Brain/drug effects , Brain/metabolism , Cell Line, Tumor , Dose-Response Relationship, Drug , Drug Delivery Systems , Feasibility Studies , Female , Humans , Infusions, Intra-Arterial , Male , Rats , Xenograft Model Antitumor Assays
14.
J Neurooncol ; 124(3): 333-43, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26108656

ABSTRACT

Intraarterial (IA) drug delivery is a physiologically appealing strategy as drugs are widely distributed throughout the tumor capillary network and high regional tissue concentrations can be achieved with low total doses. IA treatment of glioblastoma multiforme (GBM) has been attempted since the 1950s but success has been elusive. Although IA treatments have been embraced for the treatment of retinoblastoma and advanced liver cancers, this has not been the case for GBM. The development of IA drug delivery for the treatment of brain cancer over the last several decades reveals a number of critical oversights. For example, very few studies took into consideration the underlying hydrodynamic factors. Therapeutic failures were often blamed on an inability to penetrate the blood brain barrier or on the streaming of drugs. Similarly, there were few methods to investigate the ultra-fast pharmacokinetics of IA drugs. Despite past failures, clinical interest in IA drugs for the treatment of GBM persists. The advent of modern imaging methods along with a better understanding of hydrodynamics factors, better appreciation of the complex morphology of GBM, improved drug selection and formulations, and development of methods to minimize treatment-related neurological injury, promise to considerably advance the application of IA drugs for GBM treatment. There are several clinical trials with IA treatments in the National Trial Registry that are actively recruiting patients. This review of IA drug delivery for GBM treatment is therefore timely and is intended to assess how this method of drug delivery could be better applied to future treatments.


Subject(s)
Antineoplastic Agents/administration & dosage , Brain Neoplasms/drug therapy , Drug Delivery Systems , Glioblastoma/drug therapy , Humans , Infusions, Intra-Arterial
15.
J Neurooncol ; 123(1): 27-33, 2015 May.
Article in English | MEDLINE | ID: mdl-25868602

ABSTRACT

Injection of a PDGF-B expressing retrovirus into the subcortical white matter of adult rats induces the rapid formation of brain tumors that have the histological features of glioblastoma. In contrast, when the same retrovirus is injected into the spinal cord of adult rats the resulting tumors are more indolent and display a unique histology characterized by nests of tumor cells separated by a dense vascular network without areas of necrosis. To study whether these differences are determined by the tumor cell of origin or due to microenvironmental influences, we conducted a series of transplantation experiments. Cells were independently isolated from PDGF-induced brain and cord tumors then subsequently transplanted into naive rat forebrains and spinal cords. The resulting tumors were characterized by histological analysis, marker expression profiling, PDGFR subtyping, and latency to tumor-induced morbidity. Tumor phenotypes were found to be consistently predicted by the tissue into which they were transplanted rather than by the tissue of origin. These results suggest that tumor microenvironment rather than the tumor cell of origin may be the primary determinant of glioma phenotype in the model presented.


Subject(s)
Brain Neoplasms/pathology , Glioma/pathology , Platelet-Derived Growth Factor/pharmacology , Spinal Cord Neoplasms/pathology , Tumor Microenvironment , Animals , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Disease Models, Animal , Fluorescent Antibody Technique , Glioma/drug therapy , Glioma/metabolism , Male , Phenotype , Rats , Rats, Sprague-Dawley , Spinal Cord Neoplasms/drug therapy , Spinal Cord Neoplasms/metabolism
16.
Neurosurg Focus ; 39(2): E8, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26235025

ABSTRACT

OBJECT While extent of resection has been shown to correlate with outcomes after myxopapillary ependymoma (MPE) resection, the effect of capsular violation has not been well studied. The role of adjuvant radiation also remains controversial. In this paper the authors' goals were to evaluate outcomes following resection of MPE based on intraoperative capsular violation and to explore the role of adjuvant radiotherapy in cases of capsular violation. METHODS A retrospective review of patients undergoing resection of MPE at 2 academic institutions between 1990 and 2013 was performed. Cases with dissemination at presentation, less than 12 months of follow-up, or incomplete records were excluded. Extent of resection was defined as en bloc if all visible tumor was removed without capsular violation, gross-total resection (GTR) if all visible tumor was removed, but with capsular violation, and subtotal resection (STR) if a known residual was left at the time of surgery. Postoperative MR images were reviewed to confirm the extent of resection. Primary outcomes were progression-free survival (PFS) and overall recurrence rates. The effects of extent of resection, capsular violation, and adjuvant radiotherapy on recurrence rates and PFS were analyzed using Kaplan-Meier statistics. Associations between recurrence and preoperative variables were evaluated using Fisher exact methods and t-tests where appropriate. RESULTS Of the 107 patients reviewed, 58 patients (53% were male) met inclusion criteria. The mean age at surgery was 40.8 years (range 7-68 years). The median follow-up was 51.5 months (range 12-243 months). Extent of resection was defined as en bloc in 46.5% (n = 27), GTR in 34.5% (n = 20), and STR in 18.9% (n = 11). No recurrences were noted in the en bloc group, compared with 15% (n = 3) and 45% (n = 5) in the GTR and STR groups. En bloc resection was achieved most frequently in tumors involving the conus. Twelve patients (20%) underwent adjuvant radiotherapy following either STR or GTR. The overall recurrence rate was 13.8% (n = 8), and the 5-year PFS was 81%. Capsular violation was associated with a higher recurrence rate (p = 0.005). Adjuvant radiotherapy showed a nonsignificant trend of lower recurrence rates (16.7% vs 31.6%, p = 0.43) and longer PFS at 5 years (83.3% vs 49.9%, p = 0.16) in cases of capsular violation. CONCLUSIONS A strong correlation between capsular violation and recurrence was found following removal of MPE and should be assessed when defining extent of resection in future studies. Although the use of adjuvant radiotherapy in cases of capsular violation showed a trend toward improved PFS, further investigation is needed to establish its role as salvage therapy also appears to be effective at halting disease progression.


Subject(s)
Disease Progression , Ependymoma/surgery , Neoplasm Recurrence, Local/epidemiology , Neurosurgical Procedures/methods , Radiotherapy, Adjuvant/methods , Spinal Cord Neoplasms/surgery , Adolescent , Adult , Aged , Child , Combined Modality Therapy/methods , Disease-Free Survival , Ependymoma/complications , Ependymoma/pathology , Ependymoma/radiotherapy , Female , Follow-Up Studies , Humans , Male , Middle Aged , Neoplasm Recurrence, Local/radiotherapy , Neoplasm Recurrence, Local/surgery , Radiotherapy, Adjuvant/statistics & numerical data , Retrospective Studies , Spinal Cord Neoplasms/complications , Spinal Cord Neoplasms/pathology , Spinal Cord Neoplasms/radiotherapy , Treatment Outcome , Young Adult
17.
J Neurooncol ; 120(3): 489-97, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25195130

ABSTRACT

Rapid first pass uptake of drugs is necessary to increase tissue deposition after intraarterial (IA) injection. Here we tested whether brain tissue deposition of a nanoparticulate liposomal carrier could be enhanced by coordinated manipulation of liposome surface charge and physiological parameters, such as IA injection during transient cerebral hypoperfusion (TCH). Different degrees of blood-brain barrier disruption were induced by focused ultrasound in three sets of Sprague-Dawley rats. Brain tissue retention was then compared for anionic, cationic, and charge-neutral liposomes after IA injection combined with TCH. The liposomes contained a non-exchangeable carbocyanine membrane optical label that could be quantified using diffuse reflectance spectroscopy (DRS) or visualized by multispectral imaging. Real-time concentration-time curves in brain were obtained after each liposomal injection. Having observed greater tissue retention of cationic liposomes compared to other liposomes in all three groups, we tested uptake of cationic liposomes in C6 tumor bearing rats. DRS and multispectral imaging of postmortem sections revealed increased liposomal uptake by the C6 brain tumor as compared to non-tumor contralateral hemisphere. We conclude that regional deposition of liposomes can be enhanced without BBB disruption using IA injection of cationic liposomal formulations in healthy and C6 tumor bearing rats.


Subject(s)
Brain/metabolism , Cations/chemistry , Drug Delivery Systems/methods , Injections, Intra-Arterial/methods , Liposomes/administration & dosage , Liposomes/chemistry , Animals , Blood-Brain Barrier/diagnostic imaging , Blood-Brain Barrier/metabolism , Brain/drug effects , Brain Neoplasms/drug therapy , Brain Neoplasms/metabolism , Capillary Permeability/physiology , Carbocyanines/administration & dosage , Carbocyanines/chemistry , Cell Line, Tumor , Feasibility Studies , Liposomes/pharmacokinetics , Male , Nanoparticles/administration & dosage , Nanoparticles/chemistry , Neoplasm Transplantation , Optical Imaging , Rats, Sprague-Dawley , Spectrum Analysis , Ultrasonography/methods
18.
J Neurosurg ; 140(2): 450-462, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-37877963

ABSTRACT

OBJECTIVE: Direct cerebral revascularization is considered as one of the most technically challenging operations in neurosurgery. Technical errors are often not identified during the case, but only after the recirculation stage, making management crucial at that time of the procedure. In this study, the authors sought to describe troubleshooting of the technical errors encountered in initially failed bypass cases. METHODS: A retrospective analysis describing a single-surgeon, single-institution experience between 2014 and 2021 was performed, based on operative reports and videos, including a 30-day follow-up period. Initially failed bypass was defined if the bypass was not patent or had a significant leak after recirculation, irrespective of the final result. RESULTS: One hundred thirty-eight bypass cases were reviewed for complex aneurysms (n = 49), moyamoya disease (n = 59), and atherosclerosis (n = 30). Fifty-one initially failed anastomoses were identified; 43 of these were the result of a technical error. Etiologies of these failed anastomoses included a clot (n = 14), vessel kinking (n = 4), spasm (n = 5), suture-related cause (n = 5), inappropriate donor or recipient (n = 3), or lack of demand (n = 8). A major leak was attributed to an uncoagulated side branch (n = 4), vessel injury due to suture/clip placement (n = 1), or inadequate suture line coverage (n = 7). Thirty-seven (86%) of 43 cases were troubleshot successfully, as salvage maneuvers included papaverine vessel massage, donor repositioning, re-anastomosis for occlusion in select cases, local hemostatic agents, and suturing or coagulating side branches in a leak. Thirty-day follow-up revealed similar rates of patency between successfully troubleshot patients (35/37) and the rest of the cases (80/87, p = 0.6). CONCLUSIONS: Three major patterns of a noncompatible bypass were found: a major leak, an acute occlusion, or a delayed occlusion. Based on the authors' experience, salvage strategies proved successful, showing an eventual high patency rate. The authors suggest a gradual, structured algorithm to address this stage in surgery that may contribute specifically to cerebrovascular neurosurgeons at the beginning of their careers.


Subject(s)
Cerebral Revascularization , Intracranial Aneurysm , Moyamoya Disease , Humans , Cerebral Revascularization/methods , Retrospective Studies , Moyamoya Disease/surgery , Intracranial Aneurysm/surgery , Anastomosis, Surgical/methods
19.
Interv Neuroradiol ; : 15910199241236821, 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38439698

ABSTRACT

INTRODUCTION: Stent-assisted coil embolization (SACE) for cerebral aneurysms requires dual antiplatelet therapy (DAPT), commonly clopidogrel plus aspirin is preferable to ticagrelor or prasugrel plus aspirin. However, there are few studies assessing the safety of the association of ticagrelor or prasugrel plus aspirin. OBJECTIVES: Compare the safety of newer P2Y12 inhibitors with clopidogrel in patients that underwent a SACE for cerebral aneurysms. METHODS: In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we searched PubMed and Embase for studies comparing newer P2Y12 inhibitors with clopidogrel in patients undergoing DAPT for SACE. Outcomes were total number of complications, number of hemorrhagic complications, and number of thromboembolic complications both intraoperative and follow-up. A random effects model was used to calculate odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: We included 1026 patients from six studies. Newer P2Y12 inhibitors were used in 562 (54,77%) patients. There were no significant differences between groups in total number of complications (OR 0.80; 95% CI 0.32, 1.99; p < 0.01; I2 = 78%), in intraoperative hemorrhagic complications (OR 0.66; 95% CI 0.09, 4.71; p = 0.68; I2 = 0%), follow-up hemorrhagic complications (OR 1.23; 95% CI 0.70, 2.15; p = 0.49; I2 = 0%), intraoperative thromboembolic complications (OR 0.43; 95% CI 0.14, 1.35; p = 0.25; I2 = 24%), and in follow-up thromboembolic complications (OR 0.89; 95% CI 0.33, 2.39; p = 0.03; I2 = 59%). CONCLUSION: In patients who underwent a SACE, newer P2Y12 inhibitors showed no differences in intraoperative and follow-up complications compared with clopidogrel.

20.
Neurocrit Care ; 18(3): 362-7, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23192335

ABSTRACT

BACKGROUND: Altered cerebral vasomotor reactivity leading to vasospasm can be seen both in patients with primary headache disorders (PHD) and in patients with subarachnoid hemorrhage (SAH). The pathogenesis of vasospasm in post-SAH patients and in headache disorder sufferers may be related. To address this hypothesis, we analyzed a large cohort of SAH patients to determine whether a diagnosis of PHD predisposes to vasospasm, delayed cerebral ischemia, or worsened clinical outcome. METHODS: Prospectively collected data from patients enrolled in the SAH Outcomes Project between 1996 and 2006 were analyzed. Patients were segregated based on whether they had a diagnosis of PHD or not and were subsequently compared for differences in clinical and radiographic outcome. RESULTS: A total of 921 SAH patients were analyzed, 265 of which had a diagnosis of PHD. In total, symptomatic vasospasm was seen in 17%, while angiographic vasospasm was seen in 28%. Vasospasm rates were similar among patients with a PHD and in those without a PHD (p > 0.05). However, on multivariate analysis new ischemic infarcts were more common in patients with a PHD as compared to patients without a PHD (p = 0.015). Functional outcomes at 3 months were similar among PHD and non-PHD patients (p > 0.05). CONCLUSION: A history of PHD is associated with an increased rate of ischemic infarcts during admission for SAH. Increased rates of vasospasm within small cerebral blood vessels may be implicated. Further studies are warranted to more closely link the mechanisms of vasospasm in PHD and SAH patients.


Subject(s)
Brain Ischemia/etiology , Headache Disorders, Primary/complications , Subarachnoid Hemorrhage/complications , Vasospasm, Intracranial/etiology , Adult , Aged , Brain Ischemia/physiopathology , Cerebral Angiography , Cerebral Infarction/etiology , Cerebral Infarction/physiopathology , Cerebrovascular Circulation/physiology , Cohort Studies , Female , Headache Disorders, Primary/physiopathology , Humans , Male , Middle Aged , Multivariate Analysis , Prospective Studies , Subarachnoid Hemorrhage/physiopathology , Vasospasm, Intracranial/physiopathology
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