Zeev Feldman

Novel, compact, intraoperative magnetic resonance imaging-guided system for conventional neurosurgical operating rooms.

OBJECTIVEPreliminary clinical experience with a novel, compact, intraoperative magnetic resonance imaging (MRI)-guided system that can be used in an ordinary operating room is presented. DESCRIPTION OF INSTRUMENTATION The system features an MRI scanner integrated with an optical and MRI tracking system. Scanning and navigation, which are operated by the surgeon, are controlled by an in-room computer workstation with a liquid crystal display screen. The scanner includes a 0.12-T permanent magnet with a 25-cm vertical gap, accommodating the patient’s head. The field of view is 11 × 16 cm, encompassing the surgical area of interest. The magnet is mounted on a transportable gantry that can be positioned under the surgical table when not in use for scanning, thus rendering the surgical environment unmodified and allowing the use of standard instruments. The features of the integrated navigation system allow flap planning and intraoperative tracking based on updated images acquired during surgery. OPERATIVE TECHNIQUE Twenty patients with brain tumors were surgically treated using craniotomy or transsphenoidal approaches. One patient underwent conscious craniotomy with cortical mapping, and two underwent electrocorticography. EXPERIENCE AND RESULTS Planning was accurate. Resection control images were obtained for all patients during surgery, with precise localization of residual tumor tissue. There were no surgical complications related to the use of the system. CONCLUSIONThis intraoperative MRI system can function in a normal operating room modified only to eliminate radiofrequency interference. The operative environment is normal, and standard instruments can be used. The scanning and navigation capabilities of the system eliminate the inaccuracies that may result from brain shift. This novel type of intraoperative MRI system represents another step toward the introduction of the modality as a standard method in neurosurgery.

Risk of venous thromboembolism in pediatric patients with brain tumors

Venous thromboembolism (VTE) is a common event in adults with malignant brain tumors approaching 24% throughout the course of the disease. The high morbidity and mortality of this complication yielded several protocols for prevention of the disease in adults undergoing neurosurgery for brain tumors and possible primary prevention afterwards. We investigated the incidence and complications of VTE in pediatric neuro‐oncology patients.

Anesthesia for magnetic resonance guided neurosurgery: initial experience with a new open magnetic resonance imaging system.

The authors present their initial experience with a compact open magnetic resonance (MR) image-guided system, (PoleStar N-10, Odin Medical Technologies, Yokneam, Israel) used in a standard operating room, modified for radio frequency (RF) shielding. The low intensity of the magnetic field (0.12T), and the ability to lower the magnet from the operative field during surgery allows for an almost routine surgical procedure, in addition to the benefits of using intraoperative MR imaging. Although an MR compatible anesthesia machine and monitoring system are used, the system offers anesthesiologists access to the patient at all times during the procedure, and the ability to use conventional surgical equipment, syringe pumps, and warming devices. Propofol and remifentanil, used for maintaining anesthesia, allow early extubation and neurological evaluation at the end of surgery. Electrocorticographic monitoring can be used during surgery for epilepsy, and awake craniotomy can be performed. More experience with this new imaging system is required to assess its influence on clinical decision making and outcome.

Metabolic and clinical markers of prognosis in the era of CT imaging in children with acute epidural hematomas

Acute epidural hematoma (AEH), a relatively common complication of head injury in children, persists in bearing high morbidity and mortality. Early establishment of prognosis could guide optimal patient allocation, and early identification of predictive signs could assist in choosing appropriate therapeutic interventions. This study aimed to delineate expeditiously obtainable prognostic markers for determining outcome in a subset of children with AEH. We reviewed our 11-year experience with 61 consecutive children <16 years old with head trauma and isolated AEH. Treatment followed a standard advanced trauma life support protocol. A medical history was obtained, and all patients underwent neurosurgical and physical evaluations. CT scans were performed, as were laboratory tests which included arterial blood gases, glucose, electrolytes (K+, Na+), hemoglobin and coagulation studies. Evaluation of the data collected on cause of injury, interval between trauma occurrence and presentation, clinical symptoms, Glasgow Coma Scale (GCS) scores, vital signs, laboratory test results, physical findings and surgical versus conservative management revealed that the best single predictors of outcome following AEH were the GCS and focal neurological deficits. Of all laboratory data obtained on admission, the blood potassium, pH and glucose test results correlated significantly with prognosis. Prognosis can be adequately and expeditiously estimated by selected markers within a comprehensive evaluation of children with AEH.

Prenatal sonographic diagnosis of lateral ventricle choroid plexus papilloma in an in vitro fertilization-induced pregnancy.

This is a report of a prenatal sonographic diagnosis of a lateral ventricle choroid plexus papilloma in an in vitro fertilization (IVF)-induced pregnancy of a 40-year-old woman. The baby was delivered at 35 weeks of gestation and surgery was performed 5 days later with a good outcome. Several cases of malignancies associated with IVF are reported in the literature. To the best of the authors’ knowledge, this is the first report of a prenatal diagnosis of choroid plexus papilloma in an IVF-induced pregnancy. The authors also review other cases of choroid plexus papilloma diagnosed prenatally by ultrasound. The theoretical association between IVF and neoplasia is also considered.

Intraoperative Magnetic Resonance Imaging for Resection of Intra-Axial Brain Lesions: A Decade of Experience Using Low-Field Magnetic Resonance Imaging, Polestar N-10, 20, 30 Systems

OBJECTIVE The aim of this study was to determine the utility of an intraoperative magnetic resonance imaging (i-MRI) system (Polestar N-10, 20, 30) in achieving maximal resection of intra-axial brain lesions. METHODS The subjects comprised 163 patients with intra-axial brain lesions who underwent resection at Sheba Medical Center using the Polestar from February 2000 through February 2012. Demographic and imaging data were obtained and analyzed retrospectively. The patients included 83 men (50.9%) and had a mean age of 43 years. High-grade gliomas were diagnosed in 72 patients, low-grade gliomas in 35, metastases in 22, and various pathologies (e.g., cavernous angiomas, juvenile pilocytic astrocytoma, pleomorphic xanthoastrocytoma, etc.) were diagnosed in 34. The majority of the lesions (84, 51.5%) were located in or near eloquent areas. Fifty-one patients had nonenhancing lesions. RESULTS We intended to achieve complete resection in 110 of 163 cases, based on preoperative imaging. Complete resection was achieved in 90 of these 110 (81.8%) cases. Intraoperative MRI led to additional resection in 42.3% of the total cases and to complete resection in 43.3% of all the cases in which a complete resection was achieved. In 76.8% of these cases, 2 intraoperative scans were sufficient to achieve complete resection. Sex, age, intent of resection, recurrence, affected side, and radiologic characteristics did not differ significantly between cases in which intraoperative MRI led to further resection and cases in which it did not. Nonenhancing lesions of all types were 3 times more likely to require additional resection after obtaining intraoperative MRIs (P = .02). CONCLUSIONS The Polestar (N-10, 20, 30) proved useful for evaluating residual intra-axial brain lesions and achieving the maximal extent of resection in 42.3% of the total cases and in 43.3% of cases in which complete resection was achieved. Intraoperative MRI led to extended resection in 46.9% of patients for whom the initial intent was to perform an incomplete resection. Nonenhancement was the only independent variable predicting the usefulness of intraoperative MRI for additional lesion resection.

Subacute Formation of Syrinx Post-Untethering of Spinal Cord

Tethered spinal cord syndrome is characterized by a pathological fixation of the cord resulting in a low situated conus medullaris below the L1–2 interspace. With growth and development, this results in excessive cord stretching causing neuronal dysfunction. Untethering of the spinal cord aims to prevent the development of neurological or orthopedic sequelae which may arise if left untreated. Various complications of this operation have been described, including pseudomeningocele, CSF fistula, and meningitis. The authors present a case of a patient who developed a symptomatic syrinx, several days following untethering of the cord. Significant neurological improvement was achieved following revision surgery. This is the first case report of a syrinx developing several days post-untethering of the cord.

The “Lasso Sign”: An Early Sonographic Sign of Posterior Meningocele

Posterior meningocele is an uncommon form of spina bifida. We present a case of unique posterior meningocele diagnosed at the early second trimester anatomical scan using 2D and 3D ultrasound. The sonographic appearance resembled “lasso”. The prenatal follow-up was uneventful, with no demonstration of tethered cord. Clinical, neurological and radiological examinations following delivery and at the age of four months were unremarkable.

Spinal Epidural Hematoma Following Cupping Glass Treatment in an Infant With Hemophilia A.

A 6 months old infant, diagnosed with a rare mutation causing severe hemophilia A, presented with spinal epidural hematoma. Parents later admitted the infant had glass cupping therapy performed within 2 weeks of the onset of symptoms. The rare mutation, rare bleeding complication, and the eventual course of therapy applied in this case will be discussed in our case report.