Evaluation of the radiation dose to the hands of orthopaedic surgeons during fluoroscopy using stored images

Data were collected from 642 orthopaedic interventions during which the images produced by X-rays were recorded. By examining these images, it is possible to determine the time that the orthopaedic surgeons’ hands were exposed to the direct radiation beam. The procedures with greater exposure to the direct beam were those involving the hand (median 15 s) and the wrist (median 13 s). Two surgeons wore a ring to measure the absorbed dose at the fingers: one on the dominant hand and the other on the non-dominant hand. The two surgeons performed 34 and 48 operations, respectively, in 14 months. The total doses measured with the rings were 2.30 and 1.04 mSv, respectively. The images of the interventions were examined, determining how much each individual hand was exposed. The interventional reference point (IRPeff (left or right)) was calculated by comparing the doses at the IRP with the exposure times of the right or the left hand. Summing the IRPeff of the two surgeons in 14 months, it is obtained the maximum values of 2.87 mGy for the left hand of one and 6.74 mGy for the right hand of the other, which are of the order of 1/100 of the annual dose limit for the extremities. © The Author(s) 2020. Published by Oxford University Press. All rights reserved

Dosimetria midollo emopoietico durante trattamento con 153Sm-EDTMP : un metodo pratico basato solo sulla raccolta delle urine

La somministrazione terapeutica di 153Sm-EDTMP per la palliazione del dolore da metastasi scheletriche da carcinoma prostatico avviene solitamente con attivit\ue0 nominale standard di 2 GBq (circa 37 MBq/kg). Tale attivit\ue0 \ue8 stata scelta per limitare la tossicit\ue0 al midollo emopoietico. La variabilit\ue0 individuale della captazione scheletrica e della conseguente dose al midollo \ue8 completamente trascurata. Pur non fornendo alcun carattere di previsione, il calcolo della dose assorbita eseguito a posteriori ha una grande validit\ue0 scientifica se viene collocato nell\u2019ampio problema della necessit\ue0 di indagare le correlazioni tra dose assorbita e tossicit\ue0 agli organi. In quest\u2019ambito, il calcolo della dose al midollo \ue8 il caso pi\uf9 importante, poich\ue9 tale tessuto \ue8 l\u2019organo critico nella stragrande maggioranza dei trattamenti medico-nucleari, ma anche il pi\uf9 complesso, poich\ue9 tale tessuto non \ue8 localizzato in un distretto, e spesso viene irraggiato in modo disuniforme. La raccolta di dati dosimetrici richiede tempo macchina e tempo uomo, organizzazione di reparto e pazienti collaboranti. Pertanto la ricerca di metodiche in grado di ridurre le risorse richieste per tali studi, senza sacrificarne l\u2019affidabilit\ue0 scientifica, \ue8 una via per favorirne lo sviluppo. Questo \ue8 lo scopo del presente lavoro

Small field output factors evaluation with a microDiamond detector over 30 Italian centers

The aim of the study was a multicenter evaluation of MLC&jaws-defined small field output factors (OF) for different linear accelerator manufacturers and for different beam energies using the latest synthetic single crystal diamond detector commercially available. The feasibility of providing an experimental OF data set, useful for on-site measurements validation, was also evaluated

Improving dose delivery accuracy with EPID in vivo dosimetry: results from a multicenter study

Purpose: To investigate critical aspects and effectiveness of in vivo dosimetry (IVD) tests obtained by an electronic portal imaging device (EPID) in a multicenter and multisystem context. Materials and methods: Eight centers with three commercial systems—SoftDiso (SD, Best Medical Italy, Chianciano, Italy), Dosimetry Check (DC, Math Resolution, LCC), and PerFRACTION (PF, Sun Nuclear Corporation, SNC, Melbourne, FL)—collected IVD results for a total of 2002 patients and 32,276 tests. Data are summarized for IVD software, radiotherapy technique, and anatomical site. Every center reported the number of patients and tests analyzed, and the percentage of tests outside of the tolerance level (OTL%). OTL% was categorized as being due to incorrect patient setup, incorrect use of immobilization devices, incorrect dose computation, anatomical variations, and unknown causes. Results: The three systems use different approaches and customized alert indices, based on local protocols. For Volumetric Modulated Arc Therapy (VMAT) treatments OTL% mean values were up to 8.9% for SD, 18.0% for DC, and 16.0% for PF. Errors due to “anatomical variations” for head and neck were up to 9.0% for SD and DC and 8.0% for PF systems, while for abdomen and pelvis/prostate treatments were up to 9%, 17.0%, and 9.0% for SD, DC, and PF, respectively. The comparison among techniques gave 3% for Stereotactic Body Radiation Therapy, 7.0% (range 4.7–8.9%) for VMAT, 10.4% (range 7.0–12.2%) for Intensity Modulated Radiation Therapy, and 13.2% (range 8.8–21.0%) for 3D Conformal Radiation Therapy. Conclusion: The results obtained with different IVD software and among centers were consistent and showed an acceptable homogeneity. EPID IVD was effective in intercepting important errors