Transrectal prostate ultrasonography: variability of interpretation.

PURPOSE

The current study was designed to compare the interpretation of the individual performing transrectal ultrasound examination (operator) with experienced individuals who interpreted the examination with and without the availability of clinical data. Inter-observer and intra-observer variability was compared to determine the reproducibility and reliability of the study.

MATERIALS AND METHODS

All patients undergoing radical prostatectomy for treatment of localized carcinoma of the prostate underwent a transrectal ultrasound examination before the procedure. The sonogram was interpreted by the operator and reviewers. The radical prostatectomy specimen was examined pathologically and the staging as determined by ultrasound was compared with the pathological findings.

RESULTS

Ultrasound operator accuracy for extracapsular extension and seminal vesicle invasion was 0.70 and 0.74, respectively, compared with the accuracy of the reviewers, which ranged from 0.59 to 0.75 and 0.44 to 0.74 for extracapsular extension and seminal vesicle invasion, respectively. In general, blinded reviews were less accurate than unblinded reviews but this was only statistically significant for 2 reviewers.

CONCLUSIONS

Although for most reviewers the addition of clinical data did not improve the accuracy of the interpretation, an advantage was noted for the operator, that is, the individual performing the examination. In general, the technical quality of the examination was related to the accuracy of the readings.