Protocol modifications for CT perfusion (CTp) examinations of abdomen-pelvic tumors: Impact on radiation dose and data processing time
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Avinash R. Kambadakone & Ashish Sharma & Onofrio A. Catalano & Peter F. Hahn & Dushyant V. Sahani
- چاپ و سال / کشور: 2011
Description
Purpose To evaluate the effect of CT perfusion (CTp) protocol modifications on quantitative perfusion parameters, radiation dose and data processing time. Materials & methods CTp datasets of 30 patients (21M:9F) with rectal (n=24) or retroperitoneal (n=6) tumours were studied. Standard CTp protocol included 50 sec cine-phase (0.5 sec/rotation) and delayed-phase after 70 ml contrast bolus at 5–7 ml/sec. CTp-data was sub-sampled to generate modified datasets (n=105) with cine-phase(n=15) alone, varying cine-phase duration (20-40 sec, n=45) and varying temporal sampling-interval (1–3 sec, n=45). The estimated CTp parameters (BF,BV,MTT&PS) and radiation dose of standard CTp served as reference for comparison. Results CTp with 50 sec cine-phase showed moderate to high correlation with standard CTp for BF&MTT (r=0.96&0.85) and low correlation for BV (0.75, p=0.04). Limiting cinephase duration to 30 sec demonstrated comparable results for BF&MTT, while considerable variation in CTp values existed at 20 sec. There was moderate-to-high correlation of CTp parameters with sampling interval of 1&2 sec (r=0.83–0.97, p>0.05), while at 3 sec only BF showed high correlation (r=0.96, p=0.05). Increasing sampling interval (47–60%) and reducing cine-phase duration substantially reduced dose(30.8–65%) which paralleled reduced data processing time (3–10 min). Conclusion Limiting CTp cine-phase to 30 sec results in comparable BF&MTT values and increasing cine-phase sampling interval to 2 sec provides good correlation for all CTp parameters with substantial dose reduction and improved computational efficiency.
Eur Radiol (2011) 21:1293–1300 DOI 10.1007/s00330-010-2048-4 Received: 11 July 2010 / Revised: 8 November 2010 / Accepted: 12 November 2010 / Published online: 19 January 201
