Preliminary assessment of the dose to the interventional radiologist in fluoro-CT-guided procedures

Abstract

A preliminary assessment of the occupational dose to the intervention radiologist received in fluoroscopy computerised tomography (CT) used to guide the collection of lung and bone biopsies is presented. The main aim of this work was to evaluate the capability of the reading system as well as of the available whole-body (WB) and extremity dosemeters used in routine monthly monitoring periods to measure per procedure dose values. The intervention radiologist was allocated 10 WB detectors (LiF: Mg, Ti, TLD-100) placed at chest and abdomen levels above and below the lead apron, and at both right and left arms, knees and feet. A special glove was developed with casings for the insertion of 11 extremity detectors (LiF:Mg, Cu, P, TLD-100H) for the identification of the most highly exposed fingers. The H(p)(10) dose values received above the lead apron (ranged 0.20-0.02 mSv) depend mainly on the duration of the examination and on the placement of physician relative to the beam, while values below the apron are relatively low. The left arm seems to receive a higher dose value. H(p)(0.07) values to the hand (ranged 36.30-0.06 mSv) show that the index, middle and ring fingers are the most highly exposed. In this study, the wrist dose was negligible compared with the finger dose. These results are preliminary and further studies are needed to better characterise the dose assessment in CT fluoroscopy.

Prospective Evaluation of the Radiologist's Hand Dose in CT-Guided Interventions

“…It must be mentioned that the TLD measurements were taken at eleven measurement points on the hand (proximal and distal on every finger and on the wrist). Therefore, the proximity to the direct beam path differed greatly from our measurement method [21]. The hand dose values measured at the wrist were lower (0.07 -0.57 mSv) and comparable to our measurements.…”

Gafchromic XR‐QA2 film as a complementary dosimeter for hand‐monitoring in CTF‐guided biopsies

“…For the purposes of this work, the glove developed and described by Pereira et al (13) was adapted to include five strips of Gafchromic XR‐QA2 film, approximately 7 mm wide and with the necessary length for each finger, as shown in Fig. 1.…”

“…The Gafchromic strips were cut with rounded ends, so as not to tear the plastic gloves. In addition to the 11 thermoluminescent dosimeters (TLDs) initially used, (13) an additional TLD was placed on the dorsal part of the hand, in the same location used by Buls et al, (8) to allow comparison of results. The completed glove (here designated GafTLD glove) contains a total of 12 dosimeters, as well as the five Gafchromic strips, as shown in Fig.…”

“…1. Only the left‐hand glove was fabricated, since previous results have shown that, for this particular IR, the left hand is consistently and significantly more exposed than the right hand during CTF‐guided biopsies (13) …”

“…The results presented herein are net results with the background subtracted. The methodology used for calibration and read‐out of the TLDs has been described in detail elsewhere (13) …”