Quantitative assessment of microcalcification (MC) cluster image quality is presented, in terms of cluster signal-difference-to-noise ratio (SDNR) intercomparison among digital breast tomosynthesis (DBT) and 2-dimensional (2D) and synthetic-2-dimensional (s2D) mammography. A phantom that provides realistic appearance of MC clusters located in uniform and nonuniform background was imaged in 2D and DBT, considering various scattering conditions. MC cluster SDNR differentiation is investigated with respect to MC particle size (uniform background) and surrounding parenchyma density (nonuniform background).
View Article and Find Full Text PDFA survey was conducted to evaluate the role of the surgeon and the patients' body size, on patient radiation dose in fluoroscopically guided lumbar discectomy and fusion (LDF) procedures. Fluoroscopy time (FT), kerma area product (KAP), cumulative dose (CD), as well as anatomical and technical data were recorded for 100 patients, who underwent single or multi-level posterior LDF, which was carried out by three senior neurosurgeons utilising a C-arm fluoroscopy system. The patients were divided into three groups based on the body mass index (BMI) values (normal, overweight, obese) and the neurosurgeon that performed each procedure (surgeon 1, surgeon 2, surgeon 3).
View Article and Find Full Text PDFThe objective of this study was to survey breast dose in screening mammography, establish institutional doses and compare them with the corresponding dose values. Three hundred women between the ages of 40 and 80 years old participated in the study. All mammographic examinations were performed with a digital mammography system.
View Article and Find Full Text PDFThe purpose of the current study was to provide useful data, which may help neurosurgeons to manage the patient dose and image quality in spinal surgery procedures, utilising a phantom and a test object. The kerma area product, cumulative dose (CD) and entrance surface dose (ESD) rate on the phantom and image intensifier were measured, for selectable fields of view (FOVs), fluoroscopy modes, two geometric magnifications and various phantom thicknesses. The images were subjectively evaluated regarding low-contrast detectability and high-contrast resolution.
View Article and Find Full Text PDFDose audit is important towards optimisation of patients' radiation protection in diagnostic radiography. In this study, the effect of the body mass index (BMI) on radiation dose received by 1869 adult patients undergoing chest, abdomen, lumbar spine, kidneys and urinary bladder (KUB) and pelvis radiography in an X-ray room with a digital radiography system was investigated. Patients were categorised into three groups (normal, overweight and obese) based on the BMI values.
View Article and Find Full Text PDFA local survey was conducted, to evaluate the radiation dose to adult patients who underwent diagnostic X-ray examinations. Patient-related and technical data were recorded, in 1504 patients, for each of the 11 individual projections, of the 7 most common examinations performed in an X-ray room, with 1 digital radiography system. The patient entrance surface air kerma (ESAK) and the effective dose (ED) were calculated based on the X-ray tube output and the exposure parameters, as well as utilisation of suitable conversion coefficients, respectively.
View Article and Find Full Text PDFBackground And Purpose: Brain CT Perfusion (CTP) is an X-ray imaging technique for the assessment of brain tissue perfusion, which can be used in several different entities. The aim of this study is the evaluation of the radiation dose to patients during a comprehensive brain CT prescription protocol (CPP) consisting of an unenhanced brain CT, a brain CT angiography and a CTP scan.
Materials And Methods: Eighteen patients were studied using an 80-slice CT system, with an iterative reconstruction algorithm.
In this study, institutional (local) diagnostic reference levels (LDRLs) and action levels (ALs) for spine interventional procedures are reported. Fluoroscopy time (FT), kerma area product (KAP), cumulative dose (CD), as well as anatomical, clinical and technical factors affecting procedure complexity were recorded for 156 patients who underwent cervical and thoraco-lumbar interventions. Patient entrance surface dose (ESD), effective dose (ED), thyroid absorbed dose and gonadal dose were also estimated, based on KAP measurements.
View Article and Find Full Text PDFThe patient radiation doses, in conjunction with the operator experience, in therapeutic endoscopic retrograde cholangiopancreatography (ERCP) procedures, performed in our hospital, were obtained. Ninety-six patients participated in the study and were divided into 3 groups, based on the operator experience. The dosemetric indices, fluoroscopy time (FT), cumulative dose (Ka,r) and air kerma-area product (PKA), were collected.
View Article and Find Full Text PDFRadiation protection is of particular importance in paediatric radiology. In this study, the influence of increased body mass index (BMI) in radiation dose and associated risk was investigated for paediatric patients aged 5-6.5 years, undergoing chest (64 patients) or abdomen (64 patients) radiography.
View Article and Find Full Text PDFA 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.
View Article and Find Full Text PDFCervical discectomy and fusion (CDF) is a minimally invasive procedure, where the accurate placement of the implants is accomplished using fluoroscopic guidance. Therefore, the evaluation of the radiation dose becomes mandatory. The purpose of the current study was to assess patient dose during fluoroscopically guided anterior and/or posterior CDF procedures.
View Article and Find Full Text PDFEndoscopic retrograde cholangiopancreatography (ERCP) is a standard technique for the diagnosis and treatment of disorders of the pancreas or bile ducts. The aim of this study was the measurement of the radiation dose to patients during therapeutic ERCP procedures, in order to estimate the patient effective dose (ED). Fifteen patients were studied using a fluoroscopy system equipped with automatic brightness control and pulse fluoroscopy mode.
View Article and Find Full Text PDFPurpose: The aim of the present study was the evaluation and optimization of radiation dose to the ovaries (D) in hysterosalpingography (HSG).
Methods: The study included a phantom study and a clinical one. In the phantom study, we evaluated imaging results for different geometrical setups and irradiation conditions.
Objective: To evaluate the prognostic factors for patients with stage III malignant melanoma and to identify patients at high risk of developing recurrent disease who may benefit from adjuvant therapy.
Design: Retrospective study.
Setting: Specialist hospital, USA.
Accurate three-dimensional tumor localisation in Radiotherapy, is critical to the treatment outcome, particularly when high dose gradients are present. A number of techniques have been proposed for the localisation of anatomical structures or markers. The present study proposes an approach to a concurrent maximisation of localisation accuracy and efficiency by correlation of tomographic and projectional images.
View Article and Find Full Text PDFChronic spondyloarthopathy is a very common disease in the elderly. Its more common symptoms are pain in the waist, sluggishness and stiffness. Sometimes, however, it presents with the symptoms of abdominal disease.
View Article and Find Full Text PDFBruns Beitr Klin Chir (1971)
June 1969