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1.
J Neurooncol ; 168(3): 547-553, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38748050

RESUMEN

PURPOSE: The differentiation between adverse radiation effects (ARE) and tumor recurrence or progression (TRP) is a major decision-making point in the follow-up of patients with brain tumors. The advent of immunotherapy, targeted therapy and radiosurgery has made this distinction difficult to achieve in several clinical situations. Contrast clearance analysis (CCA) is a useful technique that can inform clinical decisions but has so far only been histologically validated in the context of high-grade gliomas. METHODS: This is a series of 7 patients, treated between 2018 and 2023, for various brain pathologies including brain metastasis, atypical meningioma, and high-grade glioma. MRI with contrast clearance analysis was used to inform clinical decisions and patients underwent surgical resection as indicated. The histopathology findings were compared with the CCA findings in all cases. RESULTS: All seven patients had been treated with gamma knife radiosurgery and were followed up with periodic MR imaging. All patients underwent CCA when the necessity to distinguish tumor recurrence from radiation necrosis arose, and subsequently underwent surgery as indicated. Concordance of CCA findings with histological findings was found in all cases (100%). CONCLUSIONS: Based on prior studies on GBM and the surgical findings in our series, delayed contrast extravasation MRI findings correlate well with histopathology across a wide spectrum of brain tumor pathologies. CCA can provide a quick diagnosis and have a direct impact on patients' treatment and outcomes.


Asunto(s)
Neoplasias Encefálicas , Medios de Contraste , Imagen por Resonancia Magnética , Recurrencia Local de Neoplasia , Radiocirugia , Humanos , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/patología , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/patología , Femenino , Masculino , Persona de Mediana Edad , Anciano , Adulto , Estudios de Seguimiento , Glioma/diagnóstico por imagen , Glioma/cirugía , Glioma/radioterapia , Glioma/patología , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/etiología , Traumatismos por Radiación/patología
2.
Proc Natl Acad Sci U S A ; 112(27): 8326-31, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26111795

RESUMEN

Bromodomain and extraterminal (BET) domain proteins have emerged as promising therapeutic targets in glioblastoma and many other cancers. Small molecule inhibitors of BET bromodomain proteins reduce expression of several oncogenes required for Glioblastoma Multiforme (GBM) progression. However, the mechanism through which BET protein inhibition reduces GBM growth is not completely understood. Long noncoding RNAs (lncRNAs) are important epigenetic regulators with critical roles in cancer initiation and malignant progression, but mechanistic insight into their expression and regulation by BET bromodomain inhibitors remains elusive. In this study, we used Helicos single molecule sequencing to comprehensively profile lncRNAs differentially expressed in GBM, and we identified a subset of GBM-specific lncRNAs whose expression is regulated by BET proteins. Treatment of GBM cells with the BET bromdomain inhibitor I-BET151 reduced levels of the tumor-promoting lncRNA HOX transcript antisense RNA (HOTAIR) and restored the expression of several other GBM down-regulated lncRNAs. Conversely, overexpression of HOTAIR in conjunction with I-BET151 treatment abrogates the antiproliferative activity of the BET bromodomain inhibitor. Moreover, chromatin immunoprecipitation analysis demonstrated binding of Bromodomain Containing 4 (BRD4) to the HOTAIR promoter, suggesting that BET proteins can directly regulate lncRNA expression. Our data unravel a previously unappreciated mechanism through which BET proteins control tumor growth of glioblastoma cells and suggest that modulation of lncRNA networks may, in part, mediate the antiproliferative effects of many epigenetic inhibitors currently in clinical trials for cancer and other diseases.


Asunto(s)
Neoplasias Encefálicas/genética , Proliferación Celular/genética , Glioblastoma/genética , Proteínas Nucleares/genética , ARN Largo no Codificante/genética , Factores de Transcripción/genética , Animales , Apoptosis/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/patología , Proteínas de Ciclo Celular , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glioblastoma/metabolismo , Glioblastoma/patología , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Humanos , Ratones Desnudos , Microscopía Fluorescente , Proteínas Nucleares/antagonistas & inhibidores , Proteínas Nucleares/metabolismo , Regiones Promotoras Genéticas/genética , Unión Proteica , Interferencia de ARN , ARN Largo no Codificante/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
3.
Neurosurg Rev ; 40(2): 195-211, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27180560

RESUMEN

Brachytherapy (BT) for glioblastoma multiforme (GBM) involves the use of radioactive isotopes to deliver ionizing radiation directly into the tumor bed. Its application as a means to prolong survival in GBM patients over the past few decades has come with variable success. The objective of this review is to describe the utility of BT in GBM, and to report the outcomes and adverse events associated with its use in different multimodal treatment approaches. A search of the literature was conducted using the PubMed database. The most recent search was performed in September 2015. Thirty-two series involving 1571 patients were included in our review. The longest median overall survival (MOS) following BT for newly diagnosed GBM reached 28.5 months. Overall, 1-, 2-, and 3-year survival rates were 46-89 %, 20-57 %, and 14-27 %. For recurrent GBM, the longest reported MOS after BT was 15.9 months. One-, 2- and 3-year survival rates for recurrent GBM were 10-66 %, 3-23 %, and 9-15 %. Adverse events were reported in 27 % of patients. Reoperation for radiation necrosis occurred in 4 and 27 % of patients following low- and high-dose rate BT, respectively. BT is a feasible option for extending survival in carefully selected GBM patients. As patient outcomes and overall survival improve with more aggressive radiotherapy, so does the risk of radiation-related complications. The most effective use of BT is likely as a part of multimodal treatment with other novel therapies.


Asunto(s)
Braquiterapia , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Braquiterapia/efectos adversos , Terapia Combinada , Humanos , Resultado del Tratamiento
4.
Neurosurg Rev ; 39(4): 545-55, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26815631

RESUMEN

Recently, 5-aminolevulinic acid (5-ALA) has been utilized as an adjuvant to the surgical resection of primary brain tumors and metastases. We conducted a systematic review of the literature to further understand the role of 5-ALA in neurosurgery. Our goal was to identify the utility of 5-ALA during resection by evaluating its sensitivity and specificity for different tumor types, as well as the extent of tumor resection achieved while using 5-ALA. A search of the literature was conducted using the PubMed database for the period January 1990 through May 2014. Surgical series in which 5-ALA was used for brain neoplasm resections were evaluated for tumor histology, sensitivity, specificity, extent of resection, complications, and outcomes. Twenty-two series, involving 1163 patients, were included in our review. 5-ALA sensitivity was highest in high-grade gliomas (85 %) and meningiomas (81 %). 5-ALA specificity was high in meningiomas (100 %), as well as metastases (84 %) and high-grade gliomas (82 %). Gross total resection (GTR) was achieved using 5-ALA in 66.2 % of all gliomas and 69.6 % of meningiomas, regardless of histological subtype. 5-ALA may be a useful tool in increasing the extent of resection and achieving GTR in intracranial tumors. The resection of tumors for which 5-ALA has high sensitivity and specificity, such as high-grade gliomas, may lead to an increase in extent of resection when compared to operations using only standard white light. Further evidence for the use of 5-ALA in meningiomas and certain subtypes of metastases may be needed to qualify its efficacy.


Asunto(s)
Ácido Aminolevulínico , Neoplasias Encefálicas/cirugía , Colorantes Fluorescentes , Glioma/cirugía , Neoplasias Meníngeas/cirugía , Meningioma/cirugía , Humanos , Neuronavegación/métodos , Procedimientos Neuroquirúrgicos/métodos , Cirugía Asistida por Computador/métodos
5.
Childs Nerv Syst ; 31(5): 653-63, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25726165

RESUMEN

PURPOSE: The increased efficacy of cancer treatments has led to a greater survival rate of patients with pediatric brain cancers. Therefore, it is imperative to explore the long-term consequences of therapies employed to treat pediatric brain tumors. The goal of this study was to provide a review of literature regarding the downstream psychological and psychiatric consequences experienced by adult survivors of pediatric brain cancer as a result of treatment, tumor type, or tumor location. METHODS: A PubMed MeSH search and additional online database searches were conducted to include pertinent studies that discussed psychological deficits in childhood brain cancer survivors. The studies included were subjected to data extraction to quantify relevant information for further analysis. RESULTS: A total of 17 papers with 5320 pediatric brain tumor patients were incorporated in our review. Mean age at diagnosis (8.13 ± 0.77 years), mean follow-up time (9.98 ± 3.05 years), and male-to-female ratios (1.08:1) were compiled from studies reporting this information. Incidences of depression (19 %), anxiety (20 %), suicidal ideation (10.9 %), schizophrenia and its related psychoses (9.8 %), and behavioral problem (28.7 %) were higher among pediatric brain cancer survivors than in the normal population. Craniospinal radiotherapy and/or surgery corresponded to an increased likelihood of developing adverse deficits. Astrocytomas or other glial tumors were linked to poorer outcomes. CONCLUSION: Physicians treating pediatric brain tumor patients should be aware of the possible consequences associated with treatment. Psychiatric monitoring is warranted in survivors of pediatric brain tumors, but further investigation is needed to elucidate late outcomes regarding tumor type and location.


Asunto(s)
Neoplasias Encefálicas/psicología , Trastornos Mentales/epidemiología , Sobrevivientes/psicología , Neoplasias Encefálicas/complicaciones , Niño , Estudios de Seguimiento , Humanos , Incidencia , Trastornos Mentales/etiología , Trastornos Mentales/psicología , Salud Mental , Factores de Riesgo , Ideación Suicida
6.
Cancer Invest ; 32(6): 299-302, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24766304

RESUMEN

While current treatment remains universal for glioblastoma, recent evidence has demonstrated marked heterogeneity in their molecular profiles. Due to the near universal rate of recurrence, attention has focused on individualized treatment and subgroup population differences that may influence the efficacy of adjuvant therapy. Recent studies have implicated chemo-radioresistant GBM stem cells (GSCs) in the propagation of heterogeneous tumor profiles. As a result, there has been a shift to classify and target GSCs in order to increase survival and delay relapse. The overall objective of our editorial is to highlight current failures in GBM treatment and to propose novel personalized methods to correct our shortcomings in GBM treatment.


Asunto(s)
Neoplasias Encefálicas/genética , Glioblastoma/genética , Recurrencia Local de Neoplasia/genética , Células Madre Neoplásicas , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/radioterapia , Resistencia a Antineoplásicos , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Glioblastoma/radioterapia , Humanos , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/radioterapia , Medicina de Precisión
7.
Br J Neurosurg ; 28(4): 438-46, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24432794

RESUMEN

Glioblastoma multiforme (GBM) is an aggressive tumor with poor survival outcomes and limited treatment options. We conducted a literature review to compare the survival outcomes of intra-arterial (IA) and intravenous (IV) chemotherapy delivery for GBM. Nine studies of IA chemotherapy infusion with 301 total patients met our criteria for inclusion and three studies contained IV treatment groups for comparison (n = 230 for IA, n = 71 for IV). The studies were grouped by either using newly diagnosed or recurrent GBM patients. In the newly diagnosed group, IV chemotherapy produced a statistically higher median overall survival (MOS; 16.3 months) compared with IA treatment (14.02 months). However, the total number of adverse events in IA chemotherapy was 1.08 per patient whereas for IV it was higher at 1.54 events per patient. Our recurrent GBM group includes only patients treated with IA chemotherapy which resulted in an average MOS of 10.84 months. This group had 2.7 adverse events per patient but no IV group is available for comparison. Historically, the survival of patients with recurrent GBM ranges from 3 to 9 months (Gil-Gil et al. Bevacizumab for the treatment of glioblastoma. Clin Med Insights Oncol 2013;7:123-35). For this reason, we believe IA chemotherapy to be a viable methodology in recurrent GBM patients to prolong survival at the risk of procedure-related complications and in newly diagnosed patients with the benefit of decreased complications.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Encefálicas/terapia , Supervivencia sin Enfermedad , Glioblastoma/terapia , Infusiones Intraarteriales , Neoplasias Encefálicas/patología , Terapia Combinada/métodos , Humanos , Infusiones Intraarteriales/métodos
8.
Cancer Invest ; 31(5): 287-308, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23614654

RESUMEN

Over the last quarter century there has been significant progress toward identifying certain characteristics and patterns in GBM patients to predict survival times and outcomes. We sought to identify clinical predictors of survival in GBM patients from the past 24 years. We examined patient survival related to tumor locations, surgical treatment, postoperative course, radiotherapy, chemotherapy, patient age, GBM recurrence, imaging characteristics, serum, and molecular markers. We present predictors that may increase, decrease, or play no significant role in determining a GBM patient's long-term survival or affect the quality of life.


Asunto(s)
Neoplasias Encefálicas/mortalidad , Glioblastoma/mortalidad , Recurrencia Local de Neoplasia/prevención & control , Biomarcadores de Tumor/sangre , Neoplasias Encefálicas/sangre , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/terapia , Terapia Combinada , Glioblastoma/sangre , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Mutación , Pronóstico , Factores de Riesgo , Sobrevivientes
9.
J Neurooncol ; 112(2): 141-52, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23344789

RESUMEN

Differentiating post radiation necrosis from progression of glioma and pseudoprogression poses a diagnostic conundrum for many clinicians. As radiation therapy and temozolomide chemotherapy have become the mainstay of treatment for higher-grade gliomas, radiation necrosis and post treatment changes such as pseudoprogression have become a more relevant clinical problem for neurosurgeons and neurooncologists. Due to their radiological similarity to tumor progression, accurate recognition of these findings remains paramount given their vastly different treatment regimens and prognoses. However, no consensus has been reached on the optimal technique to discriminate between these two lesions. In order to clarify the types of imaging modalities for recurrent enhancing lesions, we conducted a systematic review of case reports, case series, and prospective studies to increase our current understanding of the imaging options for these common lesions and their efficacy. In particular, we were interested in distinguishing radiation necrosis from true tumor progression. A PubMed search was performed to include all relevant studies where the imaging was used to differentiate between radiation necrosis and recurrent gliomas with post-radiation enhancing lesions. After screening for certain parameters in our study, seventeen articles with 435 patients were included in our analysis including 10 retrospective and 7 prospective studies. The average time from the end of radiation therapy to the onset of a recurrent enhancing lesion was 13.2 months. The most sensitive and specific imaging modality was SPECT with a sensitivity of 87.6 % and specificity of 97.8 %. Based on our review, we conclude that certain imaging modalities may be preferred over other less sensitive/specific techniques. Overall, tests such as SPECT may be preferable in differentiating TP (tumor progression) from RN (radiation necrosis) due to its high specificity, while nonspecific imaging such as conventional MRI is not ideal.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Diagnóstico por Imagen , Glioma/diagnóstico , Traumatismos por Radiación/diagnóstico , Diagnóstico Diferencial , Progresión de la Enfermedad , Humanos , Necrosis
10.
Oper Neurosurg (Hagerstown) ; 24(6): 630-640, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723341

RESUMEN

BACKGROUND: Passive drainage post-surgical evacuation of symptomatic chronic subdural hematoma (cSDH) is currently standard of care. High rates of infection, drain occlusion, and recurrence are associated complications. OBJECTIVE: To explore the use of a novel double-lumen active automated irrigation and aspiration system, IRRAflow (IRRAS), for patients with cSDH and compared procedural and clinical outcomes against passive drainage alone with propensity score matching (PSM) and volumetric analysis. METHODS: A prospectively maintained database was retrospectively searched for consecutive patients presenting with cSDH. One-to-one PSM of covariates (including baseline comorbidities and presentation hematoma volume) in active and passive irrigation groups was performed to adjust for treatment selection bias. Rates of hematoma clearance, catheter-related occlusion, and infection; number of revisions; and length of hospital stay were recorded. RESULTS: This study included 55 patients: active continuous irrigation-drainage-21 (21 post-PSM) and passive drainage-34 (21 post-PSM). For PSM groups, a significantly higher rate of hematoma clearance was obtained in the active irrigation-drainage group (0.5 ± 0.4 vs 0.4 ± 0.5 mL/day) and in the passive drainage group; odds ratio (OR) = 1.291 (CI: 1.062-1.570, P = .002) and a significantly lower rate of catheter-related infections (OR = 0.051; CI: 0.004-0.697, P = .039). A nonsignificantly lower hematoma expansion rate at discharge was noted in the active irrigation-drainage group (4.8% vs 23.8%; OR = 0.127; P = .186). No statistical difference in all-cause in-hospital mortality or discharge Glasgow Coma Scale score was observed between groups. CONCLUSION: Active and automated continuous irrigation plus drainage after cSDH surgical evacuation resulted in faster hematoma clearance and led to favorable clinical outcomes and low complication and revision rates compared with passive irrigation.


Asunto(s)
Hematoma Subdural Crónico , Humanos , Estudios Retrospectivos , Hematoma Subdural Crónico/cirugía , Puntaje de Propensión , Trepanación/métodos , Drenaje/métodos
11.
World Neurosurg ; 164: 281-289, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35636668

RESUMEN

Cerebral proliferative angiopathy (CPA) is a rare cerebrovascular pathology that presents with unique clinical features due to distinct histologic, angiographic, and pathophysiologic characteristics that separate it from classical arteriovenous malformation. The disorder is characterized by uncontrolled angiogenesis in which functional brain parenchyma is interspersed with abnormal vascular channels without a distinct nidus. Common presenting symptoms include headache, seizures, and stroke-like symptoms. Hemorrhagic presentations are rare in contrast to the typical presentations of classical arteriovenous malformation. Here, we report a young woman with a history of a suspected connective tissue disorder who presented to the emergency department with worsening headaches in a delayed fashion after experiencing minor head trauma and was found to have a left-sided subdural hematoma. Angiography confirmed a diagnosis of CPA after abnormal cortical vasculature was noted during the patient's craniotomy. A systematic review of CPA cases described in the literature was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, with the findings discussed.


Asunto(s)
Trastornos Cerebrovasculares , Malformaciones Arteriovenosas Intracraneales , Angiografía Cerebral , Femenino , Cefalea , Hematoma Subdural/diagnóstico por imagen , Hematoma Subdural/etiología , Hematoma Subdural/cirugía , Humanos , Malformaciones Arteriovenosas Intracraneales/complicaciones , Malformaciones Arteriovenosas Intracraneales/diagnóstico por imagen , Malformaciones Arteriovenosas Intracraneales/cirugía
12.
Lasers Surg Med ; 43(10): 975-83, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22109727

RESUMEN

BACKGROUND AND OBJECTIVES: Laser tissue soldering (LTS) is a promising technique for tissue fusion but is limited by the lack of reproducibility particularly when the amount of indocyanine green (ICG) applied as energy absorber cannot be controlled during the soldering procedure. Nanotechnology enables the control over the quantitative binding of the ICG. The aim of this study was to establish a highly reproducible and strong tissue fusion using ICG packed nanoshells. By including the chromophore in the soldering scaffold, dilution of the energy absorber during the soldering procedure is prevented. The feasibility of this novel nanoshell soldering technique was studied by assessing the local heating of the area and tensile strength of the resulting fused tissue. STUDY DESIGN/MATERIALS AND METHODS: Nanoshells with a diameter of 250-270 nm were loaded with ICG and included in a porous polycaprolactone (PCL) scaffold doped with albumin solder. The nanoshell scaffold was used in a flexible, semi-dry formulation suitable for surgical use. Heat development, tensile strength as well as tissue damage were assessed. RESULTS: Rabbit aortic arteries were successfully soldered using an ICG packed nanoshell scaffold. Tensile strengths of these nanoshell soldered anastomoses were found to be 734 ± 327 mN (median = 640 mN). Thermal damage was restricted to the adventitia at the irradiated area. In addition, absorber dilution was prevented during the soldering procedure resulting in significantly lower variance in maximum temperature (P = 0.03) compared to the classical liquid ICG soldering technique. CONCLUSION: Using nanoshells, controlled amounts of chromophore could successfully be bound into the polymer scaffold. Diode laser soldering of vascular tissue using ICG-nanoshell scaffolds leads to strong and reproducible tissue fusion. With optimally chosen settings of irradiation time, nanoshells coating and scaffold properties, our improved LTS procedure demonstrates the potential for a clinically applicable anastomosis technique.


Asunto(s)
Aorta/cirugía , Verde de Indocianina , Láseres de Semiconductores/uso terapéutico , Nanocáscaras , Adhesivos Tisulares , Andamios del Tejido , Técnicas de Cierre de Heridas , Anastomosis Quirúrgica/métodos , Animales , Estudios de Factibilidad , Terapia por Láser/métodos , Nanocáscaras/química , Poliaminas , Conejos , Reproducibilidad de los Resultados , Dióxido de Silicio , Temperatura , Resistencia a la Tracción , Andamios del Tejido/química
13.
Acta Neurochir Suppl ; 112: 45-53, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21691987

RESUMEN

Microsurgical suturing is the standard for cerebral bypass surgery, a technique where temporary occlusion is usually necessary. Non-occlusive techniques such as excimer laser-assisted non-occlusive anastomosis (ELANA) have certainly widened the spectrum of treatment of complex cerebrovascular situations, such as giant cerebral aneurysms, that were otherwise non-treatable. Nevertheless, the reduction of surgical risks while widening the spectrum of indications, such as a prophylactic cerebral bypass, is still a main aim, that we would like to pursue with our sutureless tissue fusion research. The primary concern in sutureless tissue fusion- and especially in tissue fusion of cerebral vessels- is the lack of reproducibility, often caused by variations in the thermal damage of the vessel. This has prevented this novel fusion technique from being applicable in daily surgical use. In this overview, we present three ways to further improve the laser tissue soldering technique.In the first section entitled "Laser Tissue Soldering Using a Biodegradable Polymer," a porous polymer scaffold doped with albumin (BSA) and indocyanine green (ICG) is presented, leading to strong and reproducible tensile strengths in tissue soldering. Histologies and future developments are discussed.In the section "Numerical Simulation for Improvement of Laser Tissue Soldering," a powerful theoretical simulation model is used to calculate temperature distribution during soldering. The goal of this research is to have a tool in hand that allows us to determine laser irradiation parameters that guarantee strong vessel fusion without thermally damaging the inner structures such as the intima and endothelium.In a third section, "Nanoparticles in Laser Tissue Soldering," we demonstrate that nanoparticles can be used to produce a stable and well-defined spatial absorption profile in the scaffold, which is an important step towards increasing the reproducibility. The risks of implanting nanoparticles into a biodegradable scaffold are discussed.Step by step, these developments in sutureless tissue fusion have improved the tensile strength and the reproducibility, and are constantly evolving towards a clinically applicable anastomosis technique.


Asunto(s)
Coagulación con Láser , Resistencia a la Tracción/fisiología , Ingeniería de Tejidos , Andamios del Tejido , Injerto Vascular/métodos , Simulación por Computador , Humanos , Polímeros , Factores de Tiempo
14.
Cureus ; 13(11): e19891, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34976503

RESUMEN

Craniotomy, cranioplasty, and craniofacial procedures may involve reoperation for additional treatment of the primary pathological condition or treatment of complications, requiring removal of previously placed hardware. During removal of the titanium hardware, there is a risk of losing, dropping, or misplacing the titanium screws because of their small size. There are also instances of difficulty disengaging the screw from the screwdriver. We describe the use of a plastic specimen cup in retrieving titanium screws after detaching them from the screwdriver by screwing the screw into the cup, thus rapidly and safely securing and storing screws for collection/discarding or possible reuse. When the empty screwdriver is used to retrieve and unscrew the titanium screw from the cranial flap or the skull bone, a plastic specimen cup should be placed adjacent to the site of screw removal. Once the screw is removed, while it is still fastened to the screwdriver, it is immediately re-screwed and secured onto the base of the plastic specimen cup, which is then placed into a second plastic specimen cup. This method prevents misplacement or dropping of the screw that may otherwise occur when manipulating the screw on or off the screwdriver and avoids perforating the surgeon's glove during handling. We describe the adjunctive use of a plastic specimen cup when removing cranial screws and hardware to rapidly and safely detach the screw and prevent the misplacement, dropping, or loss of screws intraoperatively that results in additional operative time and personnel assistance.

15.
World Neurosurg ; 131: 252-263.e2, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31376551

RESUMEN

BACKGROUND: Glioblastoma (GBM) is the most common and deadly form of brain tumor. After standard treatment of resection, radiotherapy, and chemotherapy, the 5-year survival is <5%. In recent years, research has uncovered several potential targets within the Notch signaling pathway, which may lead to improved patient outcomes. METHODS: A literature search was performed for articles containing the terms "Glioblastoma" and "Receptors, Notch" between 2003 and July 2015. Of the 62 articles retrieved, 46 met our criteria and were included in our review. Nine articles were identified from other sources and were subsequently included, leaving 55 articles reviewed. RESULTS: Of the 55 articles reviewed, 47 used established human GBM cell lines. Seventeen articles used human GBM surgical samples. Forty-five of 48 articles that assessed Notch activity showed increased expression in GBM cell lines. Targeting the Notch pathway was carried out through Notch knockdown and overexpression and targeting δ-like ligand, Jagged, γ-secretase, ADAM10, ADAM17, and Mastermindlike protein 1. Arsenic trioxide, microRNAs, and several other compounds were shown to have an effect on the Notch pathway in GBM. Notch activity in GBM was also shown to be associated with hypoxia and certain cancer-related molecular pathways such as PI3K/AKT/mTOR and ERK/MAPK. Most articles concluded that Notch activity amplifies malignant characteristics in GBM and targeting this pathway can bring about amelioration of these effects. CONCLUSIONS: Recent literature suggests targeting the Notch pathway has great potential for future therapies for GBM.


Asunto(s)
Neoplasias Encefálicas/terapia , Glioblastoma/terapia , Proteínas de Neoplasias/antagonistas & inhibidores , Receptores Notch/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Proteínas ADAM/antagonistas & inhibidores , Secretasas de la Proteína Precursora del Amiloide/antagonistas & inhibidores , Antineoplásicos/farmacología , Trióxido de Arsénico/farmacología , Neoplasias Encefálicas/irrigación sanguínea , Hipoxia de la Célula , Línea Celular Tumoral , Técnicas de Silenciamiento del Gen , Glioblastoma/irrigación sanguínea , Humanos , Proteínas Inhibidoras de la Diferenciación/antagonistas & inhibidores , Factores de Transcripción de Tipo Kruppel/antagonistas & inhibidores , MicroARNs/farmacología , Microvasos , Terapia Molecular Dirigida/métodos , Netrina-1/antagonistas & inhibidores , Niclosamida/farmacología , Receptores Notch/genética , Receptores del Activador de Plasminógeno Tipo Uroquinasa/antagonistas & inhibidores , Resveratrol/farmacología , Transducción de Señal/genética , Tretinoina/farmacología
16.
J Neurosurg ; 108(3): 567-74, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18312105

RESUMEN

OBJECT: The treatment of complex cerebrovascular or skull base pathological conditions necessitates a microsurgical blood flow preservation or augmentative revascularization procedure as either an adjunctive safety measure or a definitive treatment. The brain is susceptible to ischemia, and procedure-related risks can be minimized by the reduction of occlusion time or the use of a nonocclusive technique. The authors therefore analyzed the feasibility of an automatic device (C-Port xA, Cardica) designed for constructing an end-to-side anastomosis with or without flow interruption for a middle cerebral artery (MCA) bypass in a human cadaveric model and in an in vivo craniotomy simulation model. METHODS: Four Thiel-fixated human head specimens were prepared using 8 standard pterional craniotomies. The sylvian fissure was opened to access the anterior circulation and in particular the MCA. The length of the individual vessel segments was measured. The C-Port xA was tested on each of the 8 exposures. In addition the C-Port xA was deployed in an in vivo craniotomy simulator model in 10 New Zealand rabbits (a total of 20 anastomoses) by using the abdominal aorta jump graft model. RESULTS: Short-term patency was assessed by angiography and histological findings. In all 8 sylvian exposures, construction of an MCA anastomosis with the aid of the C-Port xA was feasible. All 20 jump graft anastomoses performed in the in vivo craniotomy simulator were found to be patent. CONCLUSIONS: The anatomical studies as well as the in vivo craniotomy simulation studies demonstrated that the dimensions of the automated end-to-side anastomosis device are suitable for an extracranial-intracranial high-flow bypass on the MCA. Further miniaturization and special adaptation of this device would allow bypass procedures to more proximal intracranial vessels.


Asunto(s)
Revascularización Cerebral/instrumentación , Craneotomía , Aneurisma Intracraneal/cirugía , Microcirugia/instrumentación , Arteria Cerebral Media/cirugía , Anastomosis Quirúrgica/métodos , Animales , Aorta Abdominal , Cadáver , Revascularización Cerebral/métodos , Modelos Animales de Enfermedad , Estudios de Factibilidad , Humanos , Conejos
17.
Lasers Surg Med ; 40(10): 716-25, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19065561

RESUMEN

BACKGROUND AND OBJECTIVES: In this in vitro feasibility study we analyzed tissue fusion using bovine serum albumin (BSA) and Indocyanine green (ICG) doped polycaprolactone (PCL) scaffolds in combination with a diode laser as energy source while focusing on the influence of irradiation power and albumin concentration on the resulting tensile strength and induced tissue damage. MATERIALS AND METHODS: A porous PCL scaffold doped with either 25% or 40% (w/w) of BSA in combination with 0.1% (w/w) ICG was used to fuse rabbit aortas. Soldering energy was delivered through the vessel from the endoluminal side using a continuous wave diode laser at 808 nm via a 400 microm core fiber. Scaffold surface temperatures were analyzed with an infrared camera. Optimum parameters such as irradiation time, radiation power and temperature were determined in view of maximum tensile strength but simultaneously minimum thermally induced tissue damage. Differential scanning calorimetry (DSC) was performed to measure the influence of PCL on the denaturation temperature of BSA. RESULTS: Optimum parameter settings were found to be 60 seconds irradiation time and 1.5 W irradiation power resulting in tensile strengths of around 2,000 mN. Corresponding scaffold surface temperature was 117.4+/- 12 degrees C. Comparison of the two BSA concentration revealed that 40% BSA scaffold resulted in significant higher tensile strength compared to the 25%. At optimum parameter settings, thermal damage was restricted to the adventitia and its interface with the outermost layer of the tunica media. The DSC showed two endothermic peaks in BSA containing samples, both strongly depending on the water content and the presence of PCL and/or ICG. CONCLUSIONS: Diode laser soldering of vascular tissue using BSA-ICG-PCL-scaffolds leads to strong and reproducible tissue bonds, with vessel damage limited to the adventitia. Higher BSA content results in higher tensile strengths. The DSC-measurements showed that BSA denaturation temperature is lowered by addition of water and/or ICG-PCL.


Asunto(s)
Aorta/cirugía , Coagulación con Láser , Andamios del Tejido , Animales , Aorta/fisiología , Aorta/ultraestructura , Rastreo Diferencial de Calorimetría , Bovinos , Estudios de Factibilidad , Técnicas In Vitro , Verde de Indocianina , Poliésteres , Conejos , Albúmina Sérica Bovina , Temperatura , Resistencia a la Tracción
18.
Surg Neurol Int ; 9: 133, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30090665

RESUMEN

Background: Meningiomas are the most prevalent primary tumor of the central nervous system (CNS), and although the majority of these neoplasms are classified as benign, nearly one fourth of the lesions display an aggressive profile characterized by pleomorphic histology, high recurrence rates, and overall resistance to standard treatment. Despite the ubiquitous nature of these tumors, no adjuvant therapeutic regimen has been identified which effectively controls disease recurrence and progression after surgery and radiation, leading to a dismal prognosis in this patient population. The primary focus of this research study is, hence, to assess the recently emerging use of bevacizumab, an anti-angiogenic agent, in the treatment of meningiomas. This systematic literature review analyzes the efficacy and safety of therapeutic bevacizumab for treatment-refractory meningiomas. Methods: A systematic PubMed search was conducted according to PRISMA guidelines to identify all relevant reports investigating the anti-angiogenic agent bevacizumab in the treatment of intracranial meningiomas. The reported parameters from pertinent retrospective reviews, prospective studies, and case studies were volumetric reduction, radiographic response, clinical stability, overall survival (OS), and progression free survival (PFS) measured at 6 and 12 months postinitiation of treatment. Complications were cataloged based on the range and severity of the therapy-related toxicities. Results: A total of 11 articles, 5 retrospective series, 2 prospective trials, and 4 case reports, reporting on a total of 92 patients, were included in this review. The use of bevacizumab therapy for intracranial meningiomas demonstrated median overall PFS of 16.8 months (range: 6.5-22 months) and PFS-6 of 73% (range: 44%-93%). Conclusions: Therapeutic bevacizumab, either alone or with combination chemotherapies, for select patient populations with recurrent or progressive meningiomas, offers a treatment option that confers improved overall progression-free survival. To assess OS parameters, larger randomized controlled trials assessing the use of anti-angiogenic agents for recurrent/progressive meningiomas are warranted.

19.
Neurosurgery ; 82(3): 407-413, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29351626

RESUMEN

The University at Buffalo's neuroendovascular fellowship is one of the longest running fellowship programs in North America. The burgeoning neurointerventional workforce and the rapid growth in the neurointerventional space on the heels of groundbreaking clinical trials prompted us to assess the fellowship's academic impact and its graduates' perceptions and productivity. An anonymized web-based survey was sent to all former neuroendovascular fellows with specific questions pertaining to current practice, research and funding, and perceptions about the fellowship's impact on their skills, competitiveness, and compensation. Additionally, the h-index was calculated to assess the academic productivity of each graduated fellow. Among 50 former fellows, 42 (84%) completed the survey. The fellows came from various countries, ethnic backgrounds, and specialties including neurosurgery (n = 39, 93%), neurology (n = 2, 5%), and neuroradiology (n = 1, 2%). Twenty (48%) respondents were currently chairs or directors of their practice. Most (n = 30, 71%) spent at least 10% of their time on research activities, with 27 (64%) receiving research funding. The median h-index of all 50 former fellows was 14. The biggest gains from the fellowship were reported to be improvement in endovascular skills (median = 10 on a scale of 0-10 [highest]) and increase in competitiveness for jobs in vascular neurosurgery (median = 10), followed by increase in academic productivity (median = 8), and knowledge of vascular disease (median = 8). In an era with open calls for moratoriums on endovascular fellowships, concerns over market saturation, and pleas to improve training, fellowship programs perhaps merit a more objective assessment. The effectiveness of a fellowship program may best be measured by the academic impact and leadership roles of former fellows.


Asunto(s)
Acreditación , Procedimientos Endovasculares/educación , Becas , Medicina , Procedimientos Neuroquirúrgicos/educación , Autoevaluación (Psicología) , Acreditación/normas , Acreditación/tendencias , Adulto , Competencia Clínica/normas , Procedimientos Endovasculares/normas , Becas/tendencias , Femenino , Humanos , Masculino , Medicina/normas , Medicina/tendencias , Procedimientos Neuroquirúrgicos/normas , Procedimientos Neuroquirúrgicos/tendencias , Encuestas y Cuestionarios
20.
Cureus ; 9(1): e954, 2017 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-28168132

RESUMEN

BACKGROUND: Relationships between various ethnicities and glioma subtype have recently been established. As a tertiary referral center for Latin America and the Caribbean, our institution treats a diverse glioblastoma (GBM) population. We sought to clarify the role of ethnicity on patient prognosis in GBM and also compared these findings to a group consisting of elderly patients. We included 'elderly' as a group because the subgroups for ethnicities within them were too small. It allowed us to put in scope the effects of ethnicities on the overall survival.  Material and Methods: After Institutional Review Board approval, 235 patients with GBM were retrospectively identified. A total of 140 patients were separated into four groups: White adults (n = 47), Hispanic adults (n = 27), elderly (n = 58), and Black adults (n = 6). Overall survival (OS) was our primary endpoint. RESULTS: Overall survival in the White adult group was 24.3 months, compared to 13.0 months in the Hispanic adult group, 20.2 months in the Black group, and 13.8 months in the elderly group (p = 0.01). In the Hispanic group, hypertension (37.9%, p = 0.01) and diabetes (24.1%, p = 0.009) were significantly more prevalent compared to the White adult cohort. No difference in insurance status or postoperative complications was found between subgroups. CONCLUSION: Based on our analysis, Hispanic adults may have a decreased survival compared to White adults. However, the incidence of hypertension and diabetes was markedly higher in our Hispanic adult cohort; thus, estimating the risk of ethnicity and comorbidities on patient prognosis may be difficult. A prospective study correlating the genome and subgroup prognosis may help elucidate the role of ethnicity in GBM patients.

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