Search results for "radiosurgery"

Central Nervous System Malignancies

2021

The primitive neoplasms of the central nervous system (CNS) are a rare and heterogeneous group of malignancies. Brain metastases (BMs) are the most frequent intracranial tumor, and their incidence is rising in the last few decades. Primary tumors more often complicated by BMs are lung cancer, breast cancer, and melanoma. Neuroimaging techniques, mainly magnetic resonance imaging (MRI), play a key role for the diagnosis of BMs. The management of BMs is based on a multimodal approach, including symptomatic treatment, local treatment, such as surgery, stereotactic radiosurgery (SRS), and whole brain radiotherapy (WBRT), and systemic therapy, such as chemotherapy, target therapy, or immunothera…

Using anatomic and metabolic imaging in stereotactic radio neuro-surgery treatments

2016

Characteristics and treatment of Multiple Sclerosis-related trigeminal neuralgia: An Italian multi-centre study

2019

Abstract Background The prevalence of trigeminal neuralgia (TN) in Multiple Sclerosis (MS) patients is higher than in the general population and its management can be particularly challenging. Our aim is to describe the characteristics, treatment and prognostic factors of MS-related TN in a retrospective multicentre study. Methods Neurologists members of the RIREMS group (Rising Researchers in MS) enrolled MS patients with a TN diagnosis and filled out a spreadsheet comprising their clinical data. Results Population consisted of 298 patients. First-choice preventive treatments were carbamazepine and oxcarbazepine. A surgical procedure was performed in 81 (30%) patients, most commonly gamma …

SU-E-T-218: Octavius 4D: Commissioning and Clinical Implementation of a New Device for VMAT Verifications

2013

Purpose: To commission a new device for pre‐treatment patient specific verification of VMAT plans, which is capable of reconstructing 3D dose with high resolution. Methods: Octavius 4D system (PTW) consists of an ion chamber array embedded in a cylindrical phantom which, assisted by an inclinometer, rotates synchronously with the gantry. For VMAT plans, it measures planar dose distributions as a function of gantry angle in order to compute the resulting 3D dose distribution. There are two options for the ion chamber array: Octavius 729 (general purpose) and Octavius 1000 SRS (small field size, high resolution). We have used three linacs: two Varian Clinac iX and one TrueBeam with MLC HD 120…

A two-dimensional liquid-filled ionization chamber array prototype for small-field verification: characterization and first clinical tests.

2012

In this work we present the design, characterization and first clinical tests of an in-house developed two-dimensional liquid-filled ionization chamber prototype for the verification of small radiotherapy fields and treatments containing such small fields as in radiosurgery, which consists of 2 mm × 2 mm pixels arranged on a 16×8 rectangular grid. The ionization medium is isooctane. The characterization of the device included the study of depth, field-size and dose-rate dependences, which are sufficiently moderate for a good operation at therapy radiation levels. However, the detector presents an important anisotropic response, up to ≃ 12% for front versus near-lateral incidence, which can …

Uvulopalatoplasty by radiosurgery

2003

A fully automatic approach for multimodal PET and MR image segmentation in gamma knife treatment planning

2017

The aim of this study is to combine Biological Target Volume (BTV) segmentation and Gross Target Volume (GTV) segmentation in stereotactic neurosurgery.Our goal is to enhance Clinical Target Volume (CTV) definition, including metabolic and morphologic information, for treatment planning and patient follow-up.We propose a fully automatic approach for multimodal PET and MR image segmentation. This method is based on the Random Walker (RW) and Fuzzy C-Means clustering (FCM) algorithms. A total of 19 brain metastatic tumors, undergone stereotactic neuro-radiosurgery, were retrospectively analyzed. A framework for the evaluation of multimodal PET/MRI segmentation is presented, considering volume…

END-TO-END TEST IN STEREOTACTIC RADIOSURGERY TREATMENTS THROUGH HELICAL TOMOTHERAPY

2020

Dose verification with EPR/alanine dosimeters in Helical Tomotherapy Stereotactic Radiosurgery (HT SRS) treatments

2016

Intracranial stereotactic radiosurgery (SRS) is a technique to deliver an ablative radiation dose with an extremely sharp dose gradient to small brain tumors. This tecnique allows to deliver high doses of radiation to the tumor sparing the surrounding healthy tissue. In this study the accuracy of the dose delivered in a SRS session by a non conventional radiotherapy machine, the TomoTherapy Hi-Art System, was investigated using an "end-to-end" test. This is perfome d by means of alanine Electron Paramagnetic Resonance (EPR) pe llets. The response of these dosimeters is compared to that of gafchromic films which are particularly suitable for two-dimensional dose verification providing accura…

The value of serial MR imaging in the assessment of brain metastases volume control during stereotactic radiosurgery

2015

Purpose: To evaluate early tumour control capabilities of Stereotactic Radiosurgery (SRS) in the treatment of brain metastasis and the role of follow-up MR imaging. Methods and Materials: MR imaging of 54 metastases in 31 patients treated with SRS who underwent follow-up MR imaging within 12 months were retrospectively reviewed. Tumours were characterized as either enlarged (>20% volume increase), stable (follow-up volume ±20% of the initial volume), or decreased (> 0% volume decrease). Results: Within the first 6 weeks following SRS a decrease was observed in 25 (52%) of the tumours in the extent of 63% in size. Tumour reduction varied according to histopathological subtype with 38% of non…