ABSTRACT
Introduction: Ventilation/Perfusion (V/Q) PET/CT is an emerging imaging modality for regional lung function evaluation. The same carrier molecules as conventional V/Q scintigraphy are used but they are radiolabelled with gallium-68 (68Ga) instead of technetium-99m (99mTc). A recurrent concern regarding V/Q PET imaging is the radiation dose to the healthcare workers. The aim of this study was to evaluate the total effective dose and the finger dose received by the technologist when performing a V/Q PET procedure, and to compare them with the radiations doses received with conventional V/Q scintigraphy, FDG PET and Ga DOTATOC PET procedures. Materials and methods: The whole body dose measurement was performed 10 times for each of the evaluated procedures using an electronic personal dosimeter (ED). For V/Q PET and V/Q scintigraphy procedures, ventilation and perfusion stages were separately evaluated. Internal exposure was measured for ventilation procedures. Finger dose measurements were performed 5 times for each of the PET procedures using Thermoluminescence (TL) pellets. Results: The technologist effective dose when performing a V/Q PET procedure was 2.83 ± 0.67 µSv, as compared with 1.16 ± 0.34 µSv for conventional V/Q scintigraphy, 2.13 ± 0.77 µSv for [68Ga]Ga-DOTATOC, and 2.86 ± 1.79 µSv for FDG PET procedures, respectively. The finger dose for the V/Q PET procedure was similar to the dose for a [68Ga]Ga-DOTATOC scan (0.35 mSv and 0.32 mSv, respectively). Conclusion: The technologist total effective dose for a V/Q PET procedure is ~2.4 higher than the dose for a conventional V/Q scintigraphy, but in the same range than the radiation exposure when performing common PET procedures, both in terms of total effective dose or finger dose. These results should be reassuring for the healthcare workers performing a V/Q PET procedure.
ABSTRACT
OBJECTIVES: The aim of this study was to determine the accuracy of DoseMap™ software as compared to gafchromic film in real clinical practices. BACKGROUND: The radiation exposure from cardiovascular procedures could expose patients to potential risk of cancer and/or skin injury. New tools like Dosemap software were developed to estimate the patient skin dose in the cardiac catheterization laboratory. However, little data are available to validate this estimation of patient radiation skin dose. METHODS: This is a prospective cross-sectional study comparing the peak skin dose (PSD) measured by gafchromic film used as reference with an estimated PSD given by Dosemap software, in patients with BMI > 30 kg/m2 undergoing elective diagnostic and/or therapeutic interventional cardiology procedures, from April 2016 to December 2016, at the Brest University Hospital Centre, France. RESULTS: After four exclusions of patients for poor quality of gafchromic films, 90 patients were included, with 58 angiography (67.4%), 14 percutaneous interventions (16.3%), and 14 both (16.3%). The median PSDDosemap and PSDFilm were similar with 157 mGy [IQR: 99; 273] versus 158 mGy [IQR: 101; 295] (P = 0.65), respectively, with an excellent correlation (r = 0.95). The comparison between cumulative air kerma and PSDFilm was different 366 mGy [IQR: 246; 575] versus 158 mGy [IQR: 101; 295] (P < 0.01) with moderate correlation (r = 0.79). No correlation was found between the dose area product and PSDFilm (r = 0.51). CONCLUSION: DoseMap is an effective and valid method as compared to gafchromic films to estimate PSDs during interventional cardiologic procedures.
