Both peak enhancement and time to peak enhancement were significantly different between the two injection rates (P < or = .002), with faster, more intense hepatic and pancreatic enhancement at the higher rate. At 2.5 mL/sec, the pancreas reached a peak attenuation level of 65 HU at 69 sec, and the liver reached a peak of 58 HU at 87 sec. At 5.0 mL/sec, the pancreas reached a peak attenuation of 84 HU at 43 sec, and the liver reached a peak of 75 HU at 63 sec.

OBJECTIVE.We studied healthy volunteers with fat-suppressed three-dimensional

Second-look sonography by radiologists provides a valuable check of the sonographer's findings.

During the past 10 years, it has been suggested, and accepted by some, that transrectal ultrasound (TRUS) of the prostate should be used to identify a hypoechoic lesion or, if needed, guide biopsy into nonspecific areas. Retrospectively, the authors attempted to evaluate the need to identify areas that were on pathologic analysis, prostate cancer, but were not hypoechoic, but would require random/systematic biopsy to exclude prostate cancer. Six-hundred fifteen consecutive men were referred to the authors because of a concern found on digital rectal examination or because of increase in prostate-specific antigen. All patients underwent TRUS-guided biopsy of the prostate using either the four-quadrant or sextant biopsy technique. Each area undergoing biopsy was characterized as: 1) normal-appearing; 2) hypoechoic; 3) mixed echogenic (containing both hypoechoic and hyperechoic elements); 4) subtly hyperechoic (containing no calculi); or 5) isoechoic (lesion was seen because of distortion of the normal architecture). A diagnosis of carcinoma was made in 197 patients (32%). Of these, 99 (50.2%) patients had a hypoechoic lesion as the primary site, corresponding to their highest Gleason grade. Twenty-five (12.7%) had mixed echogenicity, nine (4.6%) had hyperechoic foci, and 23 (11.7%) had isoechoic biopsy-proven foci of prostate cancer. Forty-one (20.8%) patients with adenocarcinoma had normal ultrasound findings. The median Gleason grade for cancer in visible mixed echogenic and hyperechoic areas were generally higher than that for cancer in hypoechoic sites. Hypoechoic cancer sites had a Gleason grade range of 2 to 10 (median 5); mixed echogenic foci had a Gleason range of 2 to 10 (median 6); hyperechogenic cancers had a Gleason range of 2 to 8 (median 6); isoechoic cancers had a Gleason range of 2 to 7 (median 5); normal foci had a Gleason range of 2 to 8 (median 5). Results of this study suggest that 50% of clinically significant prostate cancers are not purely hypoechoic, and 37% of all diagnosed cancers contain no hypoechoic elements.

No abstract