Patient and staff dosimetry in neuroradiological procedures

Abstract

Cerebral angiography provides valuable information for use in the clinical management of patients but can result in relatively high radiation doses to patients and staff due to the extended fluoroscopy time and number of images acquired during an examination. In this study, extremity doses to radiologists and scrub nurses working in a neuroradiological centre were monitored during a 3 month period using thermoluminescent dosemeters (TLDs). Electronic personal dosemeters were also used to monitor doses above the lead apron at chest height to the radiologists, radiographers and the scrub nurses. Patient doses were recorded using a dose-area product meter whilst patient thyroid dose was measured using TLDs. Two types of examination were studied: cerebral angiography and arterial embolization. It was deduced from the results of the study that the radiologist may expect to receive a mean dose above the lead apron at chest height of 11 microSv and 25 microSv per examination when performing cerebral angiography and arterial embolization, respectively. A radiologist mean hand dose of 19.3 microSv per examination was found, whilst the average eye dose for both radiologist and scrub nurse was 13.4 microSv per examination. The patient dosimetry results revealed a mean thyroid dose of 1.7 mSv and a dose-area product of 48.5 Gy cm2 for cerebral angiography. Average dose-area product for arterial embolization was 122.2 Gy cm2 along with a mean patient thyroid dose of 3.3 mSv. More detailed patient dosimetry was also performed using a Rando anthropomorphic phantom loaded with TLDs to measure organ doses and hence estimate effective dose. A typical four vessel angiogram was found to result in a patient effective dose of 3.6 mSv.

A Comparison of Radiation Exposure between Diagnostic CTA and DSA Examinations of Cerebral and Cervicocerebral Vessels

“…2,10 In the present study, the DAP to effectivedose conversion factors for a cerebral DSA examination were 0.065 (ICRP 60) and 0.056 mSv/Gy-cm 2 (ICRP 103), which are somewhat smaller compared with those in previous reports. 2,10,11 In the present work, the smaller conversion factor for ICRP 103 is a result of the adjustment of the effective dosecalculation scheme between ICRP 60 and ICRP 103; the weight for a high brain dose is higher in ICRP 60 as opposed to ICRP 103. The conversion factors for a cervicocerebral DSA procedure were 0.067 (ICRP 60) and 0.071 mSv/Gy-cm 2 (ICRP 103) and are somewhat higher than those for the cerebral examination, due to the exposure to radiation-sensitive organs in the cervical and thoracic area (ie, thyroid, thymus, sternum, esophagus, and lungs).…”

“…[6][7][8][9] Previous investigations have indicated a large variation between radiation exposures for cervical and cerebral angiography, depending on the imaged area and the imaging technique used. 2,3,[10][11][12][13][14] A comparison of the radiation exposure between CTA and DSA methods has not been previously performed by using the same dose-measurement setup, to our knowledge. Also, the lack of reliable conversion factors for angiographic examinations complicates the comparison between the different imaging methods.…”

Dose Measurement on Both Patients and Operators during Neurointerventional Procedures Using Photoluminescence Glass Dosimeters

“…Although there have been several reports analyzing a patient's skin dose in neurointerventional procedures, [1][2][3][4][5][11][12][13][14][15][16][17][18] there are few reports that could demonstrate the regional distribution of skin dose. 5,6,19,20 In this study, we demonstrated that the ESD on the area that encompasses the right temporal and occipital region was considerably higher than that on the frontal region.…”

Measurement of cerebral circulation times using dynamic whole-brain CT-angiography: feasibility and initial experience

“…However, physicians need to weigh the potential benefits of these protocols against possible radiation risks, especially in case of repeated examinations. Effective doses of diagnostic cerebral DSA were estimated by several groups to range from 3.6 to 7.4 mSv, which is comparable to the dose range of 4D CTA, depending on various factors such as equipment, number of runs and fluoroscopy times [16,17].…”