[RADIATION-INDUCED TUMOR DEVELOPING AFTER RADIOSURGERY: WHAT ARE THE ODDS?].

Stereotactic radiosurgery is a disruptive therapeutic technique that has transformed neurosurgery and the treatment of intracranial tumors in the last few decades. Achieving tumor control rates over 90%, it is performed mostly in a single session, as an outpatient procedure involving no skin cuts, head shaving, or anesthesia, Radiosurgery stands out as a treatment modality with few and mostly transient side effects. Even though ionizing radiation (the energy used in radiosurgery) is known to be cancerogenic, radiosurgery-induced tumors have been exceedingly rare.

Targeting the vim by direct visualization of the cerebello-thalamo-cortical pathway in 3 T proton density MRI: correlation with focused ultrasound lesioning.

Surgical targeting of the ventral intermediate nucleus of the thalamus (VIM) has been historically done using indirect strategies. Here we depict the cerebello-thalamo-cortical tract (CTCT) through 3 T proton density (PD) in a cohort of patients who underwent high-intensity focus ultrasound (HIFUS) thalamotomy. Forty-seven patients treated in our institution with MR-guided HIFUS VIM thalamotomy were included in this study.

Neuro-ophthalmologic outcomes of standard versus hypo-fractionated stereotactic radiotherapy of AVPM.

Background: Most anterior visual pathway meningiomas (AVPM) are benign and slow-growing, but these tumors may affect visual functions, including visual acuity (VA) and visual field (VF). Due to location, most are treated non-surgically by fractionated stereotactic radiotherapy (FSRT), aiming to prevent tumor progression and visual functions deterioration. Unfortunately, FSRT in itself may affect visual functions.

Utility of the Polestar N30 low-field MRI system for resecting non-enhancing intra-axial brain lesions.

Background: To determine the utility of an intraoperative magnetic resonance imaging (iMRI) system, the Polestar N30, for enhancing the resection control of non-enhancing intra-axial brain lesions.

Materials And Methods: Seventy-three patients (60 males [83.3%], mean age 37 years) with intra-axial brain lesions underwent resection at Sheba Medical Centre using the Polestar between February 2012 and the end of August 2018.

LINAC radiosurgery for glomus jugulare tumors: retrospective - cohort study of 23 patients.

Background: Glomus jugulare tumors (GJTs) are uncommon and locally disruptive tumors that usually arise within the jugular foramen of the temporal bone. Surgery was the treatment of choice up until recently. In the last decades, however, radiosurgery has surfaced as a promising alternative treatment by providing excellent tumor control with low risk of cranial nerve injuries.

Brain Metastases from Ovarian Carcinoma: An Evaluation of Prognostic Factors and Treatment.

Aims And Objectives: To review a series of patients with brain metastases from ovarian cancer at a single institution. To describe treatment modalities, their outcomes and to determine prognostic factors.

Patients And Methods: Between January 1995 and December 2014, 25 patients with ovarian cancer brain metastases were treated at The Sheba Medical Center.

Decreasing battery life in subthalamic deep brain stimulation for Parkinson's disease with repeated replacements: Just a matter of energy delivered?

Background: People with Parkinson's disease (PD) treated with deep brain stimulation (DBS) with non-rechargeable implantable pulse generators (IPGs) require elective IPG replacement operations involving surgical and anesthesiologic risk. Life expectancy and the number of replacements per patient with DBS are increasing.

Objective: To determine whether IPG longevity is influenced by stimulation parameters alone or whether there is an independent effect of the number of battery replacements and IPG model.

Radiation-induced vascular malformations in the brain, mimicking tumor in MRI-based treatment response assessment maps (TRAMs).

•Of 310 brain tumors patients recruited, histology of 99 lesions was available.•Of those, 5 were histologically confirmed as radiation-induced malformations.•TRAMs cannot differentiate active tumor from vascular malformation.

[FRACTIONATED STEREOTACTIC RADIOSURGERY: A GAME CHANGER FOR NEUROSURGERY].

The article by Dr. Cohen-Inbar published in this issue of Harefuah is a timely review that brings to the general medical community the recent important developments in the field of radiosurgery--the evolution of multi-session radiosurgery [or "FSR", standing for Fractionated Stereotactic Radiation]. Radiosurgery and FSR continue to have a tremendous impact on modern neurosurgery.

Predicting and reducing cranioplasty infections by clinical, radiographic and operative parameters - A historical cohort study.

Cranioplasty is a relatively straightforward and common procedure, yet it carries a substantial rate of infection that causes major morbidity and mortality. The authors' objective was to assess the effect of various variables on the risk of developing post-cranioplasty infections, and to enable the prediction and reduction of its incidence, contributing to an improved patient-selection. The medical records, microbiologic cultures, imaging studies and operative reports of patients who have undergone cranioplasty between the years 2008-2014 at Sheba Medical Center, a tertiary care teaching hospital in Tel-Hashomer, Israel, were reviewed and evaluated for potential predictive factors of infection.

Radiosurgery for brain metastases and cerebral edema.

The objective of this study was to assess reduction in cerebral edema following linear accelerator radiosurgery (LINAC) as first line therapy for brain metastasis. We reviewed the medical records of all patients who underwent LINAC radiosurgery for brain metastasis at our institution during 2010-2012, and who had not previously undergone either surgery or whole brain radiotherapy. Data were analyzed for 55 brain metastases from 46 patients (24 males), mean age 59.

LINAC radiosurgery in the management of parasagittal meningiomas.

Background: At present, there is no general agreement for the best approach to parasagittal meningiomas. Invasion of the superior sagittal sinus is frequent and responsible for relatively high recurrence rates following conventional microsurgery. Radiosurgery has the potential to treat less accessible portions of these tumors, and its application in this pathology is increasing either as a primary or a complementary therapeutic tool.

Delayed contrast extravasation MRI: a new paradigm in neuro-oncology.

Background: Conventional magnetic resonance imaging (MRI) is unable to differentiate tumor/nontumor enhancing tissues. We have applied delayed-contrast MRI for calculating high resolution treatment response assessment maps (TRAMs) clearly differentiating tumor/nontumor tissues in brain tumor patients.

Methods: One hundred and fifty patients with primary/metastatic tumors were recruited and scanned by delayed-contrast MRI and perfusion MRI.

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.

Brain biopsy in AIDS patients: diagnostic yield and treatment applications.

Objective: Central nervous system involvement in AIDS patients can present at any stage of the disease. Brain lesions detected in imaging studies are usually treated empirically. A brain biopsy is indicated in the absence of clinical and radiologic improvement.

The LRRK2 G2019S mutation status does not affect the outcome of subthalamic stimulation in patients with Parkinson's disease.

Background: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is an established therapy for advanced Parkinson's disease (PD). The most common genetic mutation associated with PD identified to date is the G2019S mutation of the LRRK2 gene, which is highly prevalent in the Ashkenazi Jewish population. The effect of STN-DBS surgery in patients carrying this mutation has not been systematically studied.

Delayed contrast extravasation MRI for depicting tumor and non-tumoral tissues in primary and metastatic brain tumors.

The current standard of care for newly diagnosed glioblastoma multiforme (GBM) is resection followed by radiotherapy with concomitant and adjuvant temozolomide. Recent studies suggest that nearly half of the patients with early radiological deterioration post treatment do not suffer from tumor recurrence but from pseudoprogression. Similarly, a significant number of patients with brain metastases suffer from radiation necrosis following radiation treatments.

Presentation patterns and outcome of gliomatosis cerebri.

A total of 25 patients with gliomatosis cerebri (19 males and 6 females; median age 51 years, range 10-73 years) were diagnosed and treated at the Sheba Medical Center between 1995 and 2009. Of these, 3 patients were 10 years old at the time of diagnosis. Seizures were the initial clinical presentation in 19 patients, focal signs in 16 patients, headaches in 7 patients, cognitive disorder in 4 patients and rapidly progressive hemiparesis in 1 patient.

Visual outcome in meningiomas around anterior visual pathways treated with linear accelerator fractionated stereotactic radiotherapy.

Purpose: Meningiomas threatening the anterior visual pathways (AVPs) and not amenable for surgery are currently treated with multisession stereotactic radiotherapy. Stereotactic radiotherapy is available with a number of devices. The most ubiquitous include the gamma knife, CyberKnife, tomotherapy, and isocentric linear accelerator systems.

Cavernous sinus meningiomas: a large LINAC radiosurgery series.

One hundred and seventeen patients with cavernous sinus meningiomas had LINAC radiosurgery at our institution in the period 1993-2007. Six cases were lost and 9 had less than 1 year follow up. The remaining 102 patients were prospectively followed up at 1 y intervals with clinical, neuro-ophthalmological and MRI examinations.

Deep brain stimulation of the internal globus pallidus for refractory tardive dystonia.

We report a rapid, dramatic and sustained improvement following bilateral pallidal stimulation in two patients affected by intractable generalized tardive dystonia. Both patients had a chronic psychiatric disorder and developed chronic disabling generalized dystonic symptoms persisting despite prolonged withdrawal of neuroleptics and all available symptomatic treatment. The clinical benefit in both patients persisted throughout all the follow up period of 13 and 7 months.