OBJECTIVE

To determine the correlation between tortuosity index (TI) and blood flow velocity gradient (BFVG) in internal carotid artery (ICA) depending on type of tortuosity.

MATERIAL AND METHODS

The study included 72 patients divided into two groups: surgical group — 57 patients with ICA tortuosity, conservative group — 15 patients. Mean age was 62.3±10.8 years. All patients underwent CT angiography and Doppler ultrasound. TI and BFVG were assessed. TI ≥1.2 and/or BFVG >2.5 were significant. Four types of tortuosity were distinguished (C-type, S-type, coiling and kinking). Correlation between TI and BFVG was analyzed depending on type of tortuosity.

RESULTS

There were significant differences in diagnostic value of TI and BFVG depending on type of tortuosity. TI demonstrated high diagnostic significance in patients with coiling (sensitivity 100%, specificity 96.8%). In case of kinking, BFVG was the most significant indicator (sensitivity 100%, specificity 95.2%). In C-type tortuosity, BFVG demonstrated high specificity (85.7%) and moderate sensitivity (54.9%). In S-type, both parameters had moderate diagnostic value.

CONCLUSION

There is a significant correlation between TI and BFVG depending on type of tortuosity. ROC analysis confirmed high diagnostic value of these parameters for identifying hemodynamically significant tortuosity. It is recommended to consider both indicators together for more accurate analysis of indications for surgical intervention and reduction of risk of cerebrovascular disorders in patients with ICA tortuosity.