Vallepu Ramaiah Shivaprasad1, Govardhanan2, Vijaykanth Reddy Vuyyuru3, Nimisha Etayangara Katankot4, Vinay Raju5, Sowkar Umar Basha6
AIM
To find out the optimal colour Doppler parameters for eliciting twinkling artefact in cases of renal calculi.
METHODS AND MATERIALS
A total of 50 patients were included in this prospective study. Each patient was evaluated using grey-scale ultrasonography and colour Doppler using 2 MHz and 2.7 MHz.
RESULTS
Use of colour Doppler twinkling artefact with different frequencies has increased the detection rate of renal calculi. The positive predictive value was 100% for both Doppler frequencies of 2 MHz and 2.7 MHz. Sensitivity for lower frequencies of 2 MHz (49 calculi) and 2.7 MHz (34 calculi) was 98% and 68% respectively. By using lower frequency (2 MHz), the twinkling artefact intensity and sensitivity was found to be higher when compared to higher frequency (2.7 MHz).
CONCLUSION
In our study, the colour Doppler twinkling artefact evaluation of renal calculi with low and high frequencies of 2 and 2.7 MHz gave us better sensitivity and positive predictive value in detecting smaller calculi (3 mm). At 2 MHz, the twinkling artefact grading found to be high with long tail compared to medium and low tail with 2.7 MHz frequencies.
