@entity1 and staff dose during CT guided coagulation of @entity10545 , tissue biopsy and abscess drainage were evaluated retrospectively on a conventional CT scanner and prospectively on a scanner equipped with fluoroscopic CT. The computed tomography dose index (CTDI) and the individual dose equivalent, i.e. the penetrating dose for workers at a depth of 10 mm tissue, were measured. Evaluation of CTDI enabled effective dose and maximum skin entrance doses for the @entity1 to be determined. Doses were assessed for 96 CT guided interventions, including 16 drainages with average effective doses of 13.5 @entity2073 and 9.3 @entity2073 for the conventional CT scanner and the scanner with spiral CT fluoroscopy, respectively, 49 biopsies (effective doses of 8 @entity2073 and 6.1 @entity2073 , respectively), and 31 coagulations of @entity10545 (effective doses of 2.1 @entity2073 and 0.8 @entity2073 , respectively). Effective doses to @entity1 were in the same range as those observed for regular diagnostic CT examinations. Entrance skin doses were well below the 2 Gy threshold for deterministic skin effects on the CT scanner equipped with fluoroscopic function (0.03-0.33 Gy), whilst skin doses on the conventional scanner were considerably higher (0.09-1.61 Gy). This is mainly owing to the fact that on the conventional scanner mAs was rarely reduced for scans evaluating needle position whereas low mAs per rotation was selected on the scanner with the fluoroscopy option. The maximum dose to a worker measured outside the lead apron was 28 microSv for one single procedure. The mean dose per procedure was below 10 microSv for radiologists and below 1 microSv for radiographers. Correcting for attenuation of the lead apron, the doses to workers are very low.

XXXX and staff dose during CT guided biopsy, drainage and coagulation.

@entity1 :: ('9606', 'Species') :: ['patients', 'patient', 'Patient'] @entity2073 :: ('10821', 'Species') :: ['mSv'] @entity10545 :: ('MESH:D010017', 'Disease') :: ['osteoid osteoma']
@entity1 :: (9606,Species) :: ['Patient']
