Korean J Radiol.  2008 Dec;9(6):498-502. 10.3348/kjr.2008.9.6.498.

The Interobserver Agreement between Residents and Experienced Radiologists for Detecting Pulmonary Embolism and DVT with Using CT Pulmonary Angiography and Indirect CT Venography

• Yavas US
• Calisir C
• Ozkan IR

• KMID: 1118870
• DOI: http://doi.org/10.3348/kjr.2008.9.6.498

Abstract

OBJECTIVE
We wanted to prospectively evaluate the interobserver agreement between radiology residents and expert radiologists for interpreting CT images for making the diagnosis of pulmonary embolism (PE). MATERIALS AND METHODS: We assessed 112 consecutive patients, from April 2007 to August 2007, who were referred for combined CT pulmonary angiography and indirect CT venography for clinically suspected acute PE. CT scanning was performed with a 64x0.5 collimation multi-detector CT scanner. The CT studies were initially interpreted by the radiology residents alone and then the CT images were subsequently interpreted by a consensus of the resident plus an experienced general radiologist and an experienced chest radiologist. RESULTS: Two of the 112 CTs were unable to be interpreted (1.7%). Pulmonary artery clots were seen on 36 of the thoracic CT angiographies (32%). The interobserver agreement between the radiology residents and the consensus interpretation was good (a kappa index of 0.73). All of the disagreements (15 cases) were instances of overcall by the resident on the initial interpretation. Deep venous thrombosis was detected in 72% (26 of 36) of the patients who had PE seen on thoracic CT. The initial and consensus interpretations of the CT venography images disagreed for two cases (kappa statistic: 0.96). CONCLUSION: It does not seem adequate to base the final long-term treatment of PE on only the resident's reading, as false positives occurred in 13% of such cases. Timely interpretation of the CT pulmonary angiography and CT venography images should be performed by experienced radiologists for the patients with suspected PE.

Keyword

Pulmonary embolism; Computed tomography (CT); Venous thrombosis

MeSH Terms

Adult
Aged
Aged, 80 and over
Female
Humans
Male
Middle Aged
Observer Variation
*Phlebography
Pulmonary Artery/*radiography
Pulmonary Embolism/*radiography
*Tomography, X-Ray Computed
Venous Thrombosis/*radiography
Young Adult

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