A Doppler-based evaluation of peripheral lower limb arterial insufficiency in diabetes mellitus.

OBJECTIVE To determine the frequency, level and flow patterns of lower limb arterial insufficiency in diabetic patients on Doppler ultrasound study. STUDY DESIGN Cross-sectional study. PLACE AND DURATION OF STUDY Radiology Department, Civil Hospital, Karachi, from February 2007 to September 2008. METHODOLOGY One hundred adult diabetic patients with suspected peripheral vascular insufficiency irrespective of gender were included. Demographic data, presenting complaints, treatment history, and level of HbA1c were recorded. Doppler evaluated arterial status and ankle brachial index (ABI) were recorded on proforma. Statical analysis were done on SPSS version 12. RESULTS The mean HbA1c was 8.4+/-1.4 gm/dl, a majority of 77% having a controlled level of <10mg/dl. Arterial insufficiency on Doppler ultrasound was documented in 62% (p=0.016) and the dorsalis paedis artery was the predominant site of stenosis (24%). Spectral broadening and biphasic flow were salient features. The mean value of resistive index in stenotic cases was 0.563+/-0.16 with a mean velocity difference of 0.37+/-0.29 m/s (p<0.001) at the site of stenosis. CONCLUSION Peripheral vascular insufficiency was a significant finding in patients having diabetes for an average of 9.8 years, even in the presence of controlled HbA1c. The dorsalis paedis was the commonest site of involvement. The insufficiency was moderate with a biphasic flow pattern in a majority of cases. Difference in resistive index and flow velocities at and above the site of stenosis provided an important clue to the diagnosis of level of stenosis that helps in planning limb salvage management.