Dosimetry on first clinical dark‐field chest radiography
Manuela Frank, Theresa Urban, Konstantin Willer, Wolfgang Noichl, Fabio De Marco, Rafael Schick, Bernhard Gleich, Alexander Schegerer, Ursula Lechel, Pascal Meyer, J. Mohr, Thomas Koehler, Andre Yaroshenko, Ingo Maack, Thomas Pralow, Roland Proksa, Bernhard Renger, Peter B. Noël, Alexander A. Fingerle, Daniela Pfeiffer, Ernst J. Rummeny, Julia Herzen, Franz Pfeiffer
Abstract
PURPOSE: The purpose of this study was to evaluate the dose characteristic for patient examinations at the first clinical X-ray dark-field chest radiography system and to determine whether the effective patient dose is within a clinically acceptable dose range. METHODS: A clinical setup for grating-based dark-field chest radiography was constructed and commissioned, operating at a tube voltage of 70 kVp. Thermoluminescent dosimeter (TLD) measurements were conducted using an anthropomorphic phantom modeling the reference person to obtain a conversion coefficient relating dose area product (DAP) to effective patient dose at the dark-field system. For 92 patients, the DAP values for posterior-anterior measurements were collected at the dark-field system. Using the previously determined conversion coefficient, the effective dose was calculated. RESULTS: A reference person, modeled by an anthropomorphic phantom, receives an effective dose of 35 µSv. For the examined patients, a mean effective dose of 39 µSv was found. CONCLUSIONS: The effective dose at the clinical dark-field radiography system, generating both attenuation and dark-field images, is within the range of reported standard dose values for chest radiography.