OPTIMISATION OF PATIENT DOSE AND IMAGE QUALITY IN ENDOSCOPIC RETROGRADE CHOLANGIOPANCREATOGRAPHY: A PHANTOM-BASED EVALUATION.
A phantom-based study is presented aiming to optimise patient dose and image quality (IQ) in endoscopic retrograde cholangiopancreatography procedures, utilising a fluoroscopy system equipped with a flat panel detector. The patient thickness was simulated with various polymethyl methacrylate slabs, whilst IQ was evaluated using the Leeds test object. The main factors evaluated were phantom thickness, distance between phantom and detector, field of view and pulse rate. For all these factors, the dosemetric indices, entrance surface air kerma (ESAK) rate and ESAK per pulse, as well as the IQ parameters, signal-to-noise ratio and high contrast spatial resolution, were measured. Based on these measurements, the figure of merit (FOM) was estimated. The FOM and ESAK rate values indicated the optimum combination of the factors evaluated which could provide adequate clinical information, assuring minimum patient dose.
Department of Medical Physics, School of Medicine, University of Patras, 265 04Patras, Greece.
Anastasia C
AC
Hadjiconstanti
Department of Medical Physics, School of Medicine, University of Patras, 265 04Patras, Greece.
Gerasimos A T
GAT
Messaris
Department of Gastroenterology, School of Medicine, University of Patras, 265 04Patras, Greece.
Konstantinos C
KC
Thomopoulos
Department of Radiology, School of Medicine, University of Patras, 265 04Patras, Greece.
Aikaterini G
AG
Solomou
Department of Medical Physics, School of Medicine, University of Patras, 265 04Patras, Greece.
George S
GS
Panayiotakis
D002309:Cardiology; D002760:Cholangiopancreatography, Endoscopic Retrograde; D005471:Fluoroscopy; D006801:Humans; D019047:Phantoms, Imaging; D011829:Radiation Dosage; D011856:Radiographic Image Enhancement