Establishment of recurrent exposures reference levels for repeated computed tomography examinations in adult patients on a nationwide level in Slovakia.

Introduction: The study aims were: (1) to assess the incidence in 1 year, the cumulative incidences and the period prevalence in 3/5 years of the condition of patients accruing cumulative effective dose (CED) ≥ 100 mSv in health care centres providing CT examinations in Slovakia; and (2) to quantify their variability among different centres, to test the feasibility of establishing recurrent exposure reference levels (RERL) on a nationwide level.

Materials And Methods: The data were tracked during five consecutive years using the CT dose index and dose-length-product along with the patient's ID. ED was calculated using conversion factors.

Evaluating the impact of delayed-phase imaging in Contrast-Enhanced Mammography on breast cancer staging: A comparative study of abbreviated versus complete protocol.

Purpose: Contrast-enhanced mammography (CEM) is an innovative imaging tool for breast cancer detection, involving intravenous injection of a contrast medium and the assessment of lesion enhancement in two phases: early and delayed. The aim of the study was to analyze the topographic concordance of lesions detected in the early- versus delayed phase acquisitions.

Materials And Methods: Approved by the Ethics Committee (No.

Effective and organ doses in patient undergoing interventional neuroradiology procedures: A multicentre study.

Purpose: Radiation doses to adult patients submitted to cerebral angiography and intracranial aneurysms treatments were assessed by using DICOM Radiation Dose Structured Reports (RDSR) and Monte Carlo simulations. Conversion factors to estimate effective and organ doses from Kerma-Area Product (P) values were determined.

Methods: 77 cerebral procedures performed with five angiographic equipment installed in three Italian centres were analyzed.

Optimisation of protection in the medical exposure of recurrent adult patients due to computed tomography procedures: development of recurrent exposures reference levels.

Objectives: To assess the incidence (1 year) and the cumulative incidence (3 years) of the condition of patients accruing cumulative effective doses (CED) of ≥ 100 mSv and their variability among different hospitals. To establish and validate a reference level for the CED in patients with recurrent exposures (RERL) and provide a RERL value.

Methods: Data of CT exposure was collected in 9 similar hospitals.

Cumulative radiation exposure from radiological imaging in patients with Hodgkin and diffuse large b-cell lymphoma not submitted to radiotherapy.

Objective: To assess the cumulated exposure to radiation due to imaging in Hodgkin (HL) and diffuse large B-cell (DLBCL) lymphoma patients who were not submitted to radiotherapy.

Methods: The study population included 51 and 83 adult patients with HL and DLBCL, with a follow-up duration >1 year. The cumulated exposure was expressed using patient-specific data as cumulated effective dose (CED).

Patients undergoing multiphase CT scans and receiving a cumulative effective dose of ≥ 100 mSv in a single episode of care.

Objectives: To estimate the number of patients who receive a cumulative effective dose (CED) of ≥ 100 mSv from computed tomography (CT) in a single day or episode of care.

Methods: We examined 28,870 patients who underwent 49,834 CT examinations in a tertiary care centre in Italy in 2.5 years.

Conversion factors for effective dose and organ doses with the air Kerma area product in hysterosalpingography.

Histerosalpingography (HSG) remains the dominant diagnostic tool for investigation of infertility in women. Conversion factors used to estimate effective (E) and organ doses (H) from air Kerma area product (KAP) are needed to estimate patient doses in HSG, performed with state-of-the-art fluoroscopic X-ray systems with digital detectors. In this study, estimates of E and H for six critical organs/tissues, were derived on an individual basis in 120 HSG procedures and in 1410 irradiation events, performed on two X-ray systems from information available through the radiation dose structured report using Monte Carlo methods.

Peripapillary Microvascular and Neural Changes in Diabetes Mellitus: An OCT-Angiography Study.

Purpose: To evaluate peripapillary vessel density and morphology in patients with diabetes mellitus (DM) without clinical signs of diabetic retinopathy (DR) and with mild, nonproliferative DR and to correlate with peripapillary nerve fiber layer (NFL) thickness.

Methods: One hundred seventeen eyes (34 healthy controls, 54 patients with DM without DR [noDR group] and 24 patients with mild DR [DR group]) were prospectively evaluated. All subjects underwent peripapillary and macular optical coherence tomography angiography (OCT-A).

Target volume delineation for preoperative radiotherapy of rectal cancer: inter-observer variability and potential impact of FDG-PET/CT imaging.

To analyze the inter-observer variability and the potential impact of (18)F-fluorodeoxyglucose (FDG)-positron emission tomography/computed tomography (PET/CT) imaging for target volume delineation in preoperative radiotherapy of rectal cancer. Gross tumor volume (GTV) and clinical target volume (CTV) in 2 cases of rectal cancer were contoured by 10 radiation oncologists, 5 on CT and 5 on PET/CT images. Resulting volumes were analyzed by coefficient of variation (CV) and concordance index (CI).

FDG-PET/CT imaging for staging and target volume delineation in conformal radiotherapy of anal carcinoma.

Background: FDG-PET/CT imaging has an emerging role in staging and treatment planning of various tumor locations and a number of literature studies show that also the carcinoma of the anal canal may benefit from this diagnostic approach. We analyzed the potential impact of FDG-PET/CT in stage definition and target volume delineation of patients affected by carcinoma of the anal canal and candidates for curative radiotherapy.

Methods: Twenty seven patients with biopsy proven anal carcinoma were enrolled.

FDG-PET/CT imaging for staging and target volume delineation in preoperative conformal radiotherapy of rectal cancer.

Purpose: To investigate the potential impact of using (18)F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) on staging and target volume delineation for patients affected by rectal cancer and candidates for preoperative conformal radiotherapy.

Methods And Materials: Twenty-five patients diagnosed with rectal cancer T3-4 N0-1 M0-1 and candidates for preoperative radiotherapy underwent PET/CT simulation after injection of 5.18 MBq/kg of FDG.

Potential advantage of studying the lymphatic drainage by sentinel node technique and SPECT-CT image fusion for pelvic irradiation of prostate cancer.

Purpose: This study aims to investigate the in vivo drainage of lymphatic spread by using the sentinel node (SN) technique and single-photon emission computed tomography (SPECT)-computed tomography (CT) image fusion, and to analyze the impact of such information on conformal pelvic irradiation.

Methods And Materials: Twenty-three prostate cancer patients, candidates for radical prostatectomy already included in a trial studying the SN technique, were enrolled. CT and SPECT images were obtained after intraprostate injection of 115 MBq of 99mTc-nanocolloid, allowing identification of SN and other pelvic lymph nodes.

Characterization of ordered-subsets expectation maximization with 3D post-reconstruction Gauss filtering and comparison with filtered backprojection in 99mTc SPECT.

Purpose: To characterize ordered-subset expectation maximization algorithm with a fixed 3D Gauss post-reconstruction filtering (OSEM) in 99mTc SPECT as for noise, contrast and spatial resolution with varying number of subset and iteration and to compare OSEM with an optimized set of parameters, with filtered backprojection (FBP) with filter parameters typical of brain and myocardial SPECT, both with and without Chang's method of attenuation correction (AC).

Methods: SPECT images of a Jaszczak phantom with cold rod inserts, hot and cold spheres and capillary line sources were acquired. Different background activity concentrations of the phantom were simulated as well as different lesion-to-background activity ratios.