AJR Am J Roentgenol 2001 Apr;176(4):1043-7
Thromboembolic disease: variability of interobserver agreement in the
interpretation of CT venography with CT pulmonary angiography.
Garg K, Kemp JL, Russ PD, Baron AE.
OBJECTIVE: The objective of this study was to determine interobserver agreement in the
diagnosis of acute deep venous thrombosis on CT venography performed in addition to CT
pulmonary angiography. SUBJECTS AND METHODS: One hundred forty-six CT venograms of 144
patients (mean age, 61.74 years) clinically suspected of having pulmonary embolism were
analyzed prospectively and independently by two experienced thoracic and body imaging
radiologists and later by consensus of the two radiologists. The CT venography protocol
consisted of 5-mm-thick axial images at 20-mm intervals from the popliteal fossa to the
renal veins. Images were acquired 3-4 min after the start of 100-150 mL of undiluted
contrast medium administration at 4 mL/sec. Thirteen venous segments were analyzed in each
patient. There were 1586 analyzable venous segments. RESULTS: Interobserver agreement,
with the patient as the unit of analysis, was moderately good (kappa, 0.59; 95% confidence
interval [CI], 0.39-0.78). Kappa values were similar for CT venography studies performed
with 150 mL of contrast medium and 4-min delay (kappa, 0.62; 95% CI, 0.30-0.88) and with
3-min delay and 100 mL of contrast medium (kappa, 0.56; 95% CI, 0.32-0.80). Interobserver
disagreement occurred in 17 (12%) of 146 CT venography studies. Findings of 11 CT
venography studies were interpreted as negative, and six were interpreted as positive
after consensus interpretation. CONCLUSION: Interobserver agreement for deep venous
thrombosis with CT venography is moderately good.
PMID: 11264107
