Abhiraj D. Bhimani

Localized targeted antiangiogenic drug delivery for glioblastoma

Systemic delivery of antiangiogenic agents has been ineffective in improving the overall survival of patients with both primary and recurrent glioblastoma, in part due to dose-limiting toxicities. With the development of new and efficient localized delivery methods and vehicles, an otherwise lethal dose of antiangiogenic chemotherapy can be used to treat tumors while minimizing systemic side effects. Current in-vitro and in-vivo animal studies have shown promising results that encourage the pursuit towards human clinical trials for localized antiangiogenic treatment in the near future.

Surgical Complications in Intradural Extramedullary Spinal Cord Tumors - An ACS-NSQIP Analysis of Spinal Cord Level and Malignancy

BACKGROUNDnIntradural extramedullary (IDEM) spinal cord tumors account for two-thirds of all intraspinal neoplasms. Surgery for IDEM tumors carries risks for many different complications, which to date have been poorly described and quantified. In this study, we better characterize risk factors and complications for IDEM tumors, stratifying patients by spinal cord level and malignancy.nnnMETHODSnThe American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried to determine 30-day outcomes following surgery for IDEM tumors between 2005 and 2016. Patients with cervical, thoracic, and lumbar tumors were compared in terms of demographics, comorbidities, and postoperative complications. A similar analysis was performed comparing patients with benign and malignant tumors.nnnRESULTSnA total of 991 patients with IDEM tumors were identified in the cohort. The majority of tumors were thoracic (44.3%), followed by lumbar (35.4%) and cervical (20.3%). Only 6.3% of patients were readmitted within 30 days, 4.2% returned to the operating room, and 1.0% died. Significant associations were noted between spinal cord level and patient sex, age, functional status, American Society of Anesthesiologists (ASA) classification, prevalence of diabetes and hypertension, and risk of developing pneumonia. Benign and malignant tumors differed by patient sex, baseline ASA class, risk of return to the operating room, mortality, and likelihood of transfusion.nnnCONCLUSIONSnIDEM tumors are common and carry surgical risks, with different complication profiles for tumors at different spinal levels and degrees of malignancy. With definitive risk factors and outcomes, the ACS-NSQIP cohort provides a snapshot of national neurosurgery trends and outcomes in contemporary IDEM surgery.

Adult Chiari I Malformations: An Analysis of Surgical Risk Factors and Complications Using an International Database

BACKGROUNDnChiari I malformations are common in adults and a frequent procedure in neurosurgical practice. Despite several studies, there is no consensus about the indications or surgical technique for this common condition. Increasing emphasis on value-based care has emphasized reduction of readmissions and reoperations and is particularly relevant in Chiari, which has traditionally been associated with a high complication rate.nnnOBJECTIVEnTo provide a contemporary surgical profile of risk factors and complications for Chiari I malformations in adults.nnnMETHODSnThe American College of Surgeons National Surgical Quality Improvement Program database was queried to determine 30-day outcomes after surgery for Chiari I malformations in adults between 2005 and 2016. Demographics, clinical risk factors, and postoperative events were analyzed, along with reoperation and readmission reasons.nnnRESULTSnA total of 672 adult patients were identified in the cohort, with a female predominance (80%). The overall cohort readmission rate was 9.3%, and 6.8% of patients returned to the operating room. Obesity (45.7%) was predictive of both readmission and reoperation risk. Male sex and American Society of Anesthesiologists class were predictive for reoperations. The most common reason for reoperation was cerebrospinal fluid leak, which was responsible for nearly two thirds of reoperations and 4% of the cohort.nnnCONCLUSIONSnSurgery for Chiari in adults is common and carries a definitive risk profile, including rates of readmission and reoperation higher than other common neurosurgical procedures. This cohort provides a representative sample of contemporary neurosurgical outcomes in surgery for Chiari I malformations.

Management of idiopathic spinal epidural lipomatosis: a case report and review of the literature

BackgroundSpinal epidural lipomatosis (SEL) is a rare pathologic growth of histologically normal unencapsulated adipose tissue in the epidural space. Although rare, SEL can compress the spinal cord or nerve roots causing myelopathy or radiculopathy. While SEL has been associated with long-term exposure to endogenous or exogenous steroids and obesity, idiopathic forms of SEL are much rarer.Case reportIn this report, we present the first case of SEL isolated to the cervical region compressing the spinal cord in a healthy, non-obese, preadolescent patient.ConclusionIdiopathic SEL in the pediatric population is a rare entity. This is the first case of epidural lipomatosis isolated to the cervical region in an adult or child patient. In refractory, symptomatic cases of idiopathic SEL, surgical decompression is often required.

C1–C2 Fusion Versus Occipito-Cervical Fusion for High Cervical Fractures: A Multi-Institutional Database Analysis and Review of the Literature

OBJECTIVEnType II odontoid fractures of the axis (C2) account for more than 20% of all cervical fractures. If an odontoid screw is contraindicated, the treatment approach for type II C2 fractures typically involves C1-C2 posterior fusion or occipito-cervical (O-C) fusion, each of which has distinct advantages and disadvantages. In this study, postoperative outcomes of C1-C2 fusion and O-C fusion for high cervical fractures were compared.nnnMETHODSnThe American College of Surgeons National Surgical Quality Improvement Program database was queried to determine 30-day surgical outcomes of posterior C1-C2 fusion versus O-C fusion for adult patients with C2 fractures between 2005 and 2016. Demographics, operative factors, and postoperative events were analyzed, including returns to the operating room, readmission, and death.nnnRESULTSnIn total, 165 patients were identified. A majority of the patients (142, 86.1%) had independent functional status, although 133 (80.6%) had an American Society of Anesthesiologists classification ranging from 3 to 5, representing poor preoperative health. A significantly greater proportion of O-C (9.1%) versus C1-C2 fusion (1.7%) returned to the operating room (odds ratio 6.465, confidence interval 1.079-38.719, Pxa0= 0.041). The length of operation approached statistical significance (Pxa0= 0.053) between the 2 groups, with O-C fusion group having a longer average length of operation (196.4 minutes) versus the C1-C2 group (164.0 minutes).nnnCONCLUSIONSnThis study provides a snapshot of the risk profiles of C1-C2 and O-C fusion for C2 fracture, demonstrating a statistically higher risk of reoperation in O-C fusion versus C1-C2 fusion. Future randomized trials are needed to identify the preferred technique to improve patient outcomes.

Acute Surgical Risk Profile of Intramedullary Spinal Cord Tumor Resection in Pediatric Patients: A Pediatric National Surgical Quality Improvement Program Analysis

OBJECTIVEnThe purpose of the present study was to characterize the acute (30-day) surgical risk profile of pediatric patients undergoing surgical resection of intramedullary spinal cord tumors (IMSCTs).nnnMETHODSnPreoperative factors were collected from the Pediatric American College of Surgeons National Surgical Quality Improvement Program database for patients identified by Current Procedural Terminology codes for laminectomy and International Classification of Diseases codes for IMSCTs from 2012 to 2016. The postoperative outcomes were compared by tumor location and type.nnnRESULTSnThe mean age of the 139 patients meeting all inclusion criteria was 8.7 years, with a male predominance (58.7%). The cervical and thoracic IMSCT populations had worst preoperative health status, as indicated by American Society of Anesthesiologists class, and a greater proportion of malignant tumors compared with the lumbar IMSCT population. No patient died; 8.6% of the patients were readmitted, and 6.5% required reoperation. Of the 12 readmissions, 8 were required for patients with malignant tumors. The patients with cervical IMSCTs returned to the operating room at a significantly greater rate than did the thoracic and lumbar IMSCT populations. Two common reasons for reoperation in the cervical population were issues related to respiration and hydrocephalus management. The complications included 13 cases of infection, 6 of urinary tract infection, and 5 cases of surgical site infection.nnnCONCLUSIONSnResection of IMSCTs in the pediatric population is a relatively low-risk procedure in terms of acute surgical complications. However, surgeons operating in the cervical spine should be aware of the increased risk of reoperation, in particular as it pertains to respiratory issues and hydrocephalus.

Intracranial Electrode Placement for Seizures Before Temporal Lobectomy: A Risk-Benefit Analysis

BACKGROUND AND OBJECTIVEnAnterior temporal lobectomy (ATL) is the most common surgical procedure for refractory temporal lobe epilepsy. When scalp electroencephalography cannot adequately identify an epileptogenic site, electrode implantation may be used to monitor epileptic activity and localize a target focus before surgical resection. Whether the advantage of improved seizure localization justifies the added risk of electrode placement remains unclear. : The present study uses an international surgical database to explore whether a 2wo-stage approach, electrode implant followed by ATL, has a reasonable safety profile and is clinically worthwhile versus ATL alone.nnnMETHODSnData from the American College of Surgeons National Surgical Quality Improvement Program for 2005 to 2016 were queried to identify patients undergoing ATL or electrode implant for epilepsy. The 30-day postoperative outcomes were analyzed for the electrode implant and ATL groups, and individual and combined risk profiles were determined.nnnRESULTSnPatients undergoing electrode implant followed by ATL had a predicted reoperation rate of 7.6%, readmission rate of 14.6%, and a 30-day mortality rate of 1.2%. The combined rate of patients having ≥1 medical complication for 2-staged procedures was higher, at 14.7%. The most common complications encountered were urinary tract infection (2.7%) and sepsis (2.7%).nnnCONCLUSIONSnIntracranial electrode placement increases the risk of complications when added to ATL. The severity of complications from electrode placement are mild, however, and as intracranial electrode recording provides a potentially large reduction in the surgical failure risk, electrode placement may be advisable for all but the most convincing seizure foci.

Non-neurological outcomes of anterior and posterolateral approaches in the surgical treatment of thoracic disc disease: a retrospective study

BackgroundnSymptomatic thoracic disc herniation (TDH) is rare, and for those patients that fail conservative treatment, two main categories of surgical approaches exist-anterior and posterolateral. In many cases either approach would be considered equally appropriate. Recommendations in support of either anterior or posterolateral approaches are currently based on case series and expert opinion. Here, we utilize National Surgical Quality Improvement Program (NSQIP) database to determine and compare the rates of complication associated with anterior or posterolateral approaches in the treatment of TDH.nnnMethodsnAn analysis of NSQIP data from 2005 to 2014 was conducted. Patients were included based on a combination of a postoperative diagnosis of TDH. Patients were then grouped according to anterior or posterior approaches on the basis of Current Procedural Terminology (CPT) codes. Propensity score matching was performed to account for baseline demographics [sex, race, age, obesity, diabetes, smoking, history of chronic obstructive pulmonary disease (COPD), history of CHF, and American Society of Anesthesiologists (ASA) class]. The 30-day outcome measures of these patients were analyzed.nnnResultsnA total of 432 patients were identified, 80.3% underwent posterolateral and 19.7% anterior interventions. There were no significant differences in 30-day outcome measures between the anterior or posterior intervention groups. Within the matched group of 170 patients, the anterior group had significantly longer lengths of stay (5.49±3.96 vs. 4.01±4.81, P<0.0001), but there were no observed significant differences in the rate of occurrences of UTIs, pneumonias, sepsis, bleeding, intubation, or death.nnnConclusionsnPosterolateral and anterior approaches carry an equal non-neurological perioperative complication profile. Posterolateral approaches may carry shorter hospital stays compared to anterior interventions.

Preoperative steroids do not improve outcomes for intramedullary spinal tumors: a NSQIP analysis of 30-day reoperation and readmission rates

BackgroundnIntramedullary spinal cord tumors (IMSCTs) account for 8-10% of all spinal cord tumors and affect patients of all ages. Although uncommon, IMSCTs carry risk of neurological morbidity and mortality, with 5-year survival rates ranging from 50% to 80%. In this study, we utilize the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database to determine the effect of steroid administration on 30-day outcomes following surgery for IMSCTs.nnnMethodsnACS-NSQIP data for patients undergoing surgery for intramedullary tumors from 2005 to 2015 was reviewed. Patients were selected based on current procedural terminology (CPT) codes 63285 (Laminectomy, intradural, intramedullary, cervical), 63286 (Laminectomy, intradural, intramedullary, thoracic), and 63287 (Laminectomy, intradural, intramedullary, thoracolumbar). ICD-9 and ICD-10 codes were chosen based on the diagnosis of a tumor. The 30-day clinical outcome data, including reoperations and readmission rates, were collected and compared.nnnResultsnA total of 259 patients were reviewed. One hundred eighty-one patients had benign intramedullary tumors and 78 had malignant intramedullary tumors. The majority of IMSCTs were at the thoracic level (n=100), followed by the cervical (n=99), and thoracolumbar (n=39) levels. Thirty-one patients were on corticosteroid therapy prior to surgery. Patients with preoperative steroid administration had no significant difference in reoperation and readmission rates. No significant differences were noted between steroid vs. non-steroid therapy for discharge destination, length of hospital stay, or other postoperative complications.nnnConclusionsnContrary to previous reports, corticosteroid use prior to surgery for IMSCTs does not have a significant impact on 30-day risk of readmission, reoperation, and risk of postoperative complications.

Magnetic Drug Targeting: A Novel Treatment for Intramedullary Spinal Cord Tumors

Most applications of nanotechnology in cancer have focused on systemic delivery of cytotoxic drugs. Systemic delivery relies on accumulation of nanoparticles in a target tissue through enhanced permeability of leaky vasculature and retention effect of poor lymphatic drainage to increase the therapeutic index. Systemic delivery is limited, however, by toxicity and difficulty crossing natural obstructions, like the blood spine barrier. Magnetic drug targeting (MDT) is a new technique to reach tumors of the central nervous system. Here, we describe a novel therapeutic approach for high-grade intramedullary spinal cord tumors using magnetic nanoparticles (MNP). Using biocompatible compounds to form a superparamagnetic carrier and magnetism as a physical stimulus, MNP-conjugated with doxorubicin were successfully localized to a xenografted tumor in a rat model. This study demonstrates proof-of-concept that MDT may provide a novel technique for effective, concentrated delivery of chemotherapeutic agents to intramedullary spinal cord tumors without the toxicity of systemic administration.