A STUDY OF PATIENT RADIATION-DOSES IN INTERVENTIONAL RADIOLOGICAL PROCEDURES

Patient radiation doses received during interventional radiological pr ocedures can be significant. To aid in the establishment of reference dose levels, a patient dose survey has been conducted of such procedur es. A total of 288 non-coronary procedures (177 classified as diagnost ic and 111 as therapeutic) were accrued into the study. For each proce dure, the fluoroscopy screening time and the fluoroscopic and digital radiographic dose-area products were recorded in a computer database. For example, median dose-area product values (due to fluoroscopy and d igital radiography combined) of 24.2, 27.9, 69.6 and 74.7 Gy cm(2) wer e obtained for nephrostomy, biliary stent removal/insertion, cerebral angiography and percutaneous transhepatic cholangiography procedures. While the effective dose is not an accurate measure of patient risk, i t is convenient for comparing the radiological risks associated with v arious procedures. Effective doses were estimated from the total dose- area products. The respective median estimated effective dose values f or the four procedures noted above were 3.9, 4.5, 7.0 and 12.0 mSv. Wh ile an infrequently performed procedure at this institution (n=4 durin g this survey), the transjugular intrahepatic portosystemic shunt (TIP S) procedure had the greatest median dose-area product and effective d ose values: 347 Gy cm(2) and 55.5 mSv, respectively. Excluding the ext reme case of TIPS, it was found that among commonly-performed procedur es, those that are categorized as therapeutic do not necessarily prese nt a statistically significant greater radiation risk than those which are diagnostic. Comparisons between dose-area product values obtained from this study are made with data from other interventional radiolog y patient dose surveys and reasons for some differences noted are disc ussed.