Background: In literature are reported different analytical methods (AM) to choose the proper fit model and to fit data of the time-activity curve (TAC). On the other hand, Machine Learning algorithms (ML) are increasingly used for both classification and regression tasks. The aim of this work was to investigate the possibility of employing ML both to classify the most appropriate fit model and to predict the area under the curve (τ).
View Article and Find Full Text PDFPurpose: In our institution, stereotactic radiosurgery of multiple brain metastases is performed with the CyberKnife® (CK) device, using fixed/Iris collimators. In this study, nineteen fixed/Iris plans were recalculated with the multileaf collimator (MLC), to assess if it is possible to produce plans with comparable dosimetric overall quality.
Materials And Methods: For consistent comparisons, MLC plans were re-optimized and re-normalized in order to achieve the same minimum dose for the total planning target volume (PTV).
A system for internal and voluntary reporting of abnormal events in a Nuclear Medicine Therapy Unit is described. This system is based on the Internet of Things and is composed of an application for mobile devices and a wireless network of detectors. The application is addressed to healthcare professionals and is intended to be a user-friendly tool to make the reporting procedure little laborious.
View Article and Find Full Text PDFBackground: Dosimetry in molecular radiotherapy for personalized treatment is assuming a central role in clinical management of aggressive/relapsed tumors. Relapsed/refractory metastatic high-risk neuroblastoma (rrmHR-NBL) has a poor prognosis and high-activity I-mIBG therapy could represent a promising strategy. The primary aim of this case series study was to report the absorbed doses to whole-body ( ), red marrow ( ) and lesions ( ).
View Article and Find Full Text PDFObjective: 131I-meta-iodobenzylguanidine (131I-MIBG) combined with myeloablative chemotherapy represents an effective treatment in children affected by relapsed/refractory neuroblastoma (NBL) for disease palliation and in improving progression-free survival. The aim of our study is to evaluate the feasibility, safety and efficacy of tandem 131I-MIBG followed by high-dose chemotherapy with Melphalan.
Methods: Thirteen patients (age range: 3-17 years) affected by relapsed/refractory NB, previously treated according to standard procedures, were included in the study.
Objective: Radioiodine treatment (RAI-T) of differentiated thyroid carcinoma (DTC) is important to avoid disease progression, in particular in pediatric patients. For these reasons, a diagnostic scan may be useful to assess therapeutic tailored activity. The purpose of our study was to evaluate the usefulness of diagnostic whole-body scan (WBS) with iodine-123 (I) in combination with recombinant human thyroid-stimulating hormone (rh-TSH; Thyrogen) (rh-TSH-Dx-WBS), in planning RAI-T or further surgery before RAI-T in pediatric DTC.
View Article and Find Full Text PDFBackground: In a neonatal intensive care unit (NICU), preterm infants are often exposed to a large number of radiographic examinations, which could cause adjacent neonates, family caregivers and staff members to be exposed to a dose amount due to scatter radiation.
Objective: To provide information on scatter radiation exposure levels in a NICU, to compare these values with the effective dose limits established by the European Union and to evaluate the effectiveness of radiation protection devices in this setting.
Materials And Methods: Radiation exposure levels due to scatter radiation were estimated by passive detectors (thermoluminescent dosimeters) and direct dosimetric measurements (with a dose rate meter); in the latter case, an angular map of the scatter dose distribution was achieved.
Purpose: This work presents a method for estimating CT dosimetric indices with a prototype designed for suspending the phantom/ion chamber system fixed at the CT isocenter. The purpose of this study was to validate the proposed methodology, which can be used to provide a direct assessment of dosimetric indices in helical scans.
Methods: The method is based on a reference setup in which the measuring system for CT dosimetry is in a stationary configuration, i.
Purpose: The aim was to calibrate gamma cameras in the framework of the Italian multicentre study for lesion dosimetry in Ra therapy of bone metastases. Equipments of several manufacturers and different models were used.
Methods: Eleven gamma cameras (3/8- and 5/8-inch crystal) were used, acquiring planar static images with double-peak (82 and 154keV, 20% wide) and MEGP collimator.
Purpose: The aims of this work were to explore patient eligibility criteria for dosimetric studies in Ra therapy and evaluate the effects of differences in gamma camera calibration procedures into activity quantification.
Methods: Calibrations with Ra were performed with four gamma cameras (3/8-inch crystal) acquiring planar static images with double-peak (82 and 154keV, 20% wide) and MEGP collimator. The sensitivity was measured in air by varying activity, source-detector distance, and source diameter.
A 70-year-old man affected by bone metastases from castration resistant prostate cancer underwent Alpharadin ((223)Ra-dichloride) therapy (6 administrations of 50 kBq per kg i.v., once every 4 weeks).
View Article and Find Full Text PDFPurpose: Ra-dichloride is an alpha-emitting radiopharmaceutical used in the treatment of bone metastases from castration-resistant prostate cancer. Image-based dosimetric studies remain challenging because the emitted photons are few. The aim of this study was to implement a methodology for in-vivo quantitative planar imaging, and to assess the absorbed dose to lesions using the MIRD approach.
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