Srikanth Reddy Boddu MBBS, MRCS, Presenter: Nothing to Disclose

Sindhura Manubolu MBBS, Abstract Co-Author: Nothing to Disclose

Susan Geary, Abstract Co-Author: Nothing to Disclose

The role of serial compression ultrasound (CUS) and total limb complete colour ultrasound (CCUS) has always been a topic of debate in the diagnosis of lower limb DVT. However there is very limited data available in the literature on the role of repeat above knee complete colour ultrasound (AK-CCUS). The purpose of this study is to identify the significance of repeat above knee complete colour doppler ultrasound (AK-CCUS) in the detection of the above knee lower limb DVT.

Retrospective study of all the out patients with suspected lower limb deep vein thrombosis during Jan.2007-Sept.2008 (n=926). Data was obtained from DVT clinic database.All patients with repeat scan are reviewed on the hospital radiology database-CRIS to identify the risk factors and embolic events in the subsequent 3 months. Automated “Bio pool” technique with a negative predictive value of 98%-99% has been used to detect D-dimer levels. Based on the local protocol suitable patients had initial and repeat AK-CCUS.

926 patients had been reviewed in DVT clinic irrespective of D-dimer and wells score. Among the 869 patients who had initial ultrasound (1 or more-wells score/positive D-dimer) 149 patients had positive result. From 720 patients with negative initial doppler, 365 progressed to repeat doppler (3 or more-wells score/positive D-dimer) and 355 patients had no repeat doppler (1 or 2-wells score and negative D-dimer). Out of the 9 patients with positive repeat scan, 7 patients had known risk factors for DVT. Subsequent statistical analysis reveals a 90.3% pickup rate on initial doppler with one positive scan per every 5.8 scans performed, where as the repeat doppler among the patients without known risk factors for DVT had a pickup rate of 22.2% with one positive scan per every 179 scans performed

Although the repeat doppler ultrasound can increase the detection rate of lower limb above knee DVT in a non-high risk out-patient population by one positive scan per every 179 scans performed, enormous increase in the workload, limitations of the work force, local cost-effective analysis, affordability and availability of resources in the individual departments should also be taken into consideration.

Recognizing the appropriate method of doppler imaging in diagnosis of DVT, a potentially fatal condition, is vital for the appropriate utilization of resources without compromising the patient care.

Boddu, S, Manubolu, S, Geary, S, The Significance of Repeat Above-Knee Complete Color Doppler Ultrasound (AK-CCUS) in the Diagnosis of Above-Knee Lower Limb Deep Vein Thrombosis (DVT) and Its Impact on the Resources.  Radiological Society of North America 2009 Scientific Assembly and Annual Meeting, November 29 - December 4, 2009 ,Chicago IL. http://archive.rsna.org/2009/8009699.html