Contrast-enhanced transcranial Doppler sonography in the follow-up of intracranial aneurysms after endovascular treatment

Two pilot studies on a small number of patients demonstrated the feasibility of transcranial Doppler ultrasound evaluation in the follow-up of intracranial aneurysms treated with detachable coils. This prospective study aimed to assess the sensitivity of contrast-enhanced transcranial echo-Doppler in detecting partial aneurysmal occlusion following endovascular treatment. Transcranial Doppler sonography (TCD) with contrast administration and magnetic resonance angiography (MRA) or angiography were carried out after endovascular treatment in 92 patients for 98 aneurysms of the anterior circulation. In 18% of cases, the quality of ultrasound exploration was deemed unsatisfactory for evaluation of the aneurysmal site. Results were concordant in 63% of patients (49/78). When occlusion appeared satisfactory at angiography or MRA, the result was concordant with TCD in 68% of cases (44/77). When a residual aneurysm was detected, TCD sensitivity was 38% (8/18). An analysis of subgroups failed to disclose anatomic or morphological aneurysm features in which transcranial echo-Doppler is sufficiently sensitive and specific to detect possible residual aneurysm or recanalisation. In our experience, even after contrast administration TCD is not sufficiently sensitive or specific in the detection of residual aneurysm to replace angiography or MRA.