Implantation of CRT pacemaker during pregnancy: estimated fetal radiation dose.

The benefits of a cardiac resynchronization therapy (CRT) implantation are known in severe heart failure and its implantation may also be considered during pregnancy to ensure safe pregnancy and delivery for both the mother and the fetus. This study on a patient case aimed to estimate the absorbed dose (AD) to the fetus during the CRT implantation of 21st week of the pregnant woman. AD measurement was done using anthropomorphic phantom, radiophotoluminescence dosemeters and Monte Carlo simulation utilizing kerma area product (KAP) of the procedures. The measured AD for a phantom's uterus and heart was 0.116 and 14.7 mGy with total KAP of 27.9 Gycm2. The estimated actual AD to the fetus and the mother's heart was 0.004 and 1.2 mGy, with total KAP of 1.5 Gycm2. The dose to the fetus can be minimized with the optimized procedure.

Assessing Patient Radiation Exposure in Endoscopic Retrograde Cholangiopancreatography: A Multicenter Retrospective Analysis of Procedural Complexity and Clinical Factors.

BACKGROUND AND AIMS: Endoscopic retrograde cholangiopancreatography (ERCP) procedures can result in significant patient radiation exposure. This retrospective multicenter study aimed to assess the influence of procedural complexity and other clinical factors on radiation exposure in ERCP. METHODS: Data on kerma-area product (KAP), air-kerma at the reference point (Ka,r), fluoroscopy time, and the number of exposures, and relevant patient, procedure, and operator factors were collected from 2641 ERCP procedures performed at four university hospitals. The influence of procedural complexity, assessed using the American Society for Gastrointestinal Endoscopy (ASGE) and HOUSE complexity grading scales, on radiation exposure quantities was analyzed within each center. The procedures were categorized into two groups based on ERCP indications: primary sclerosing cholangitis (PSC) and other ERCPs. RESULTS: Both the ASGE and HOUSE complexity grading scales had a significant impact on radiation exposure quantities. Remarkably, there was up to a 50-fold difference in dose quantities observed across the participating centers. For non-PSC ERCP procedures, the median KAP ranged from 0.9 to 64.4 Gy·cm2 among the centers. The individual endoscopist also had a substantial influence on radiation dose. CONCLUSIONS: Procedural complexity grading in ERCP significantly affects radiation exposure. Higher procedural complexity is typically associated with increased patient radiation dose. The ASGE complexity grading scale demonstrated greater sensitivity to changes in radiation exposure compared to the HOUSE grading scale. Additionally, significant variations in dose indices, fluoroscopy times, and number of exposures were observed across the participating centers.

COMPARISON OF ORGAN-BASED TUBE CURRENT MODULATION AND BISMUTH SHIELDING IN CHEST CT: EFFECT ON THE IMAGE QUALITY AND THE PATIENT DOSE.

The aim of the study was to compare the absorbed doses and image quality of organ-based tube current modulation (OBTCM) and bismuth shielding of breasts and thyroid against regular tube current modulation in chest CT scan. An anthropomorphic phantom and MOSFET dosemeters were used to evaluate absorbed doses. Image quality was assessed from HU and noise. Relative to the reference scan, the average absorbed dose reduction with OBTCM was 5.2% and with bismuth shields 24.2%. Difference in HU values compared to the reference varied between -4.1 and 4.2 HU in OBTCM scan and between -22.2 and 118.6 HU with bismuth shields. Image noise levels varied between 10.0 to 26.3 HU in the reference scan, from 9.6 to 27.7 HU for the OBTCM scan and from 11.9 to 43.9 HU in the bismuth scan. The use of bismuth shields provided greatest dose reduction compared to the investigated OBTCM.

Fetal radiation dose in prophylactic uterine arterial embolization.

PURPOSE: The purpose of the study was to estimate the absorbed dose (AD) to the fetus for pregnant patients with placenta accreta undergoing fluoroscopy imaging during prophylactic catheterization and uterine artery embolization. We hypothesize that after optimizing the use of the radiation, this endovascular method is safe. METHODS: Catheterization was performed for seven women before their elective cesarean section. The correct position of the catheter was confirmed by a radiologist using a small bolus of contrast medium and optimized pulsed fluoroscopy imaging. For the AD measurements of the fetus, four radiophotoluminescence dosimeters were placed in the vaginal fornix. Dose area product (DAP), entrance skin exposure (ESE), fluoroscopy time (Tf), and dose rate also was recorded. RESULTS: The mean values of the radiation exposure for the seven patients were as follows: AD in the vaginal fornix was 11.2 (range 2.2-28.7) mGy, DAP 1,122 (648-2,001) cGy cm(2), ESE 120 (63-184) mGy, Tf 7:31 (5:05-11:35) min:sec, and dose rate 15 (8-21) mGy/min, respectively. CONCLUSIONS: This study revealed that the AD to the fetus due to the endovascular method can be reduced to be below the risk for developmental disorders when pulsed fluoroscopy with an optimized protocol is used without angiography exposures.