Objectives: Evaluation of radiation efficiency of dual source high-pitch (DSHP) chest CT in comparison to single source technique with special regards to individual patient anatomy. Methods: 150 consecutive patients w...Objectives: Evaluation of radiation efficiency of dual source high-pitch (DSHP) chest CT in comparison to single source technique with special regards to individual patient anatomy. Methods: 150 consecutive patients who underwent chest CT with automated tube current modulation were evaluated retrospectively and divided into three study groups, each with an equal quantity of 50 patients (DSHP vs. single source 128 slices vs. single source 16 slices). By using a dedicated workstation, volumetric analyses of each of the scanned anatomic area were performed and correlated to the individual dose length product (DLP). The calculated result was defined as dose efficiency. Results: DLP was 203 mGycm (DSHP), vs. 269 mGycm (single source) vs. 273 mGycm (16 slice CT). The total patient volume was lowest in the dual source group with 18956.3 cm3 (vs. 22481.2 cm3 vs. 22133.8 cm3). With regards to the DLP, the calculated dose efficiency of dual source CT was better than the 128 slice CT (p = 0.045) and the 16 slice CT (p < 0.01). Conclusions: DSHP CT has considerably better dose efficiency compared to 16 slice CT. Compared to 128 slice single source technique, the high-pitch mode does not cause any dose penalty when performing chest CT.展开更多
Purpose: To investigate a robot assistance device for CT-guided percutan liver biopsy. Materials and Methods: The liver of a corpse was equipped with target dummies. Four radiologists used a 16 G needle to perform bio...Purpose: To investigate a robot assistance device for CT-guided percutan liver biopsy. Materials and Methods: The liver of a corpse was equipped with target dummies. Four radiologists used a 16 G needle to perform biopsy of the target region in standard free hand technique and then used a robot system which allowed planning and aligning the trajectory path. Accuracy in terms of needle tip deviation, and time efficiency and radiation exposure in terms of effective dose for the radiologists were measured. Results: For in plane procedures, there was no significant benefit in accuracy when using the robot versus standard technique (4 mm vs. 5.6 mm, p = 0.11);timely effort was worse (443 sec vs. 405 sec, p = 0.64). For angulated punctures, a needle tip of 3.7 mm was measured by using the robotic device (vs. 10.8 mm, p < 0.01);mean biopsy duration was 490 sec (vs. 900 sec, p < 0.01). Mean radiation exposures in freehand technique were 2.4 μSv (in plane procedures) and 10.8 μSv (oblique procedures);the robotic assisted procedures were performed without additional image guidance. Conclusion: The proposed robotic assistance device may be superior for angulated interventions regarding accuracy and timely effort. Furthermore, the zero radiation exposure is a significant benefit for the interventional radiologist.展开更多
文摘Objectives: Evaluation of radiation efficiency of dual source high-pitch (DSHP) chest CT in comparison to single source technique with special regards to individual patient anatomy. Methods: 150 consecutive patients who underwent chest CT with automated tube current modulation were evaluated retrospectively and divided into three study groups, each with an equal quantity of 50 patients (DSHP vs. single source 128 slices vs. single source 16 slices). By using a dedicated workstation, volumetric analyses of each of the scanned anatomic area were performed and correlated to the individual dose length product (DLP). The calculated result was defined as dose efficiency. Results: DLP was 203 mGycm (DSHP), vs. 269 mGycm (single source) vs. 273 mGycm (16 slice CT). The total patient volume was lowest in the dual source group with 18956.3 cm3 (vs. 22481.2 cm3 vs. 22133.8 cm3). With regards to the DLP, the calculated dose efficiency of dual source CT was better than the 128 slice CT (p = 0.045) and the 16 slice CT (p < 0.01). Conclusions: DSHP CT has considerably better dose efficiency compared to 16 slice CT. Compared to 128 slice single source technique, the high-pitch mode does not cause any dose penalty when performing chest CT.
文摘Purpose: To investigate a robot assistance device for CT-guided percutan liver biopsy. Materials and Methods: The liver of a corpse was equipped with target dummies. Four radiologists used a 16 G needle to perform biopsy of the target region in standard free hand technique and then used a robot system which allowed planning and aligning the trajectory path. Accuracy in terms of needle tip deviation, and time efficiency and radiation exposure in terms of effective dose for the radiologists were measured. Results: For in plane procedures, there was no significant benefit in accuracy when using the robot versus standard technique (4 mm vs. 5.6 mm, p = 0.11);timely effort was worse (443 sec vs. 405 sec, p = 0.64). For angulated punctures, a needle tip of 3.7 mm was measured by using the robotic device (vs. 10.8 mm, p < 0.01);mean biopsy duration was 490 sec (vs. 900 sec, p < 0.01). Mean radiation exposures in freehand technique were 2.4 μSv (in plane procedures) and 10.8 μSv (oblique procedures);the robotic assisted procedures were performed without additional image guidance. Conclusion: The proposed robotic assistance device may be superior for angulated interventions regarding accuracy and timely effort. Furthermore, the zero radiation exposure is a significant benefit for the interventional radiologist.
