A study of the relationship between peak skin dose and cumulative air kerma in interventional neuroradiology and cardiology

Abstract

A study of peak skin doses (PSDs) during neuroradiology and cardiology interventional procedures has been carried out using Gafchromic XR-RV2 film. Use of mosaics made from squares held in cling film has allowed doses to the head to be mapped successfully. The displayed cumulative air kerma (CAK) has been calibrated in terms of cumulative entrance surface dose (CESD) and results indicate that this can provide a reliable indicator of the PSD in neuroradiology. Results linking PSD to CESD for interventional cardiology were variable, but CAK is still considered to provide the best option for use as an indicator of potential radiation-induced effects. A CESD exceeding 3 Gy is considered a suitable action level for triggering follow-up of patients in neuroradiology and cardiology for possible skin effects. Application of dose action levels defined in this way would affect 8% of neurological embolisation procedures and 5% of cardiology ablation and multiple stent procedures at the hospitals where the investigations were carried out. A close relationship was observed between CESD and dose-area product (DAP) for particular types of procedure, and DAPs of 200-300 Gy cm(2) could be used as trigger levels where CAK readings were not available. The DAP value would depend on the mean field size and would need to be determined for each application.

In vivo validation of Dosemap software use in interventional cardiology with dosimetrics indicators and peak skin dose evaluation

“…We noticed a good correlation between CAK and PSD film , but a worst correlation between DAP and PSD film . This is consistent with data from Neil et al, Ying and Kandaiya, and Rizk et al showing that CAK remains a better PSD predicator than DAP . However, we found a strong correlation between PSD Dosemap and PSD film .…”

Local diagnostic reference levels in diagnostic and therapeutic pediatric cardiology at a specialist pediatric hospital in South Africa

“…16 CAK, on the other hand, is directly proportional to and usually calibrated in terms of the Entrance Surface Air Kerma (ESAK). 17 It is thus well suited for estimating the risk of radiation-induced skin injury, an important consideration in FGI procedures. Such a risk may vary between patients, but a threshold of 2000 mGy CAK was suggested by ICRP publication 85.…”

Measures of patient exposure to ionizing radiation during interventional radiology procedures

“…The great feature of DAP is that it can be converted by using various factors into estimated ED and PSD (24,25). Nonetheless, the conversion factors are not standardized for all the IRP.…”

“…Exceeding a threshold, which is 2Gy results in a short-term erythema, 24-48 hours after the procedure. In cases of higher skin dose, serious skin injuries happen (3,24,25).…”