The T-Top Technique for Tandem Lesions: A Single-Center Retrospective Study

Abstract

Background: Tandem Lesions (TLs) or Tandem Occlusions (TOs) are characterized by simultaneous high-grade stenosis or occlusion of the proximal extracranial internal carotid artery and the intracranial terminal internal carotid artery or its branches. These lesions can result in stroke and pose significant challenges to endovascular treatment. This study introduces and evaluates the "T-Top technique" as an innovative approach to address TLs, assessing its safety and technical efficacy. Methods: Data from acute ischemic stroke (AIS) patients treated with the T-Top technique between September 2022 and September 2023 were retrospectively analyzed. The technique involves using the pusher wire of a stent retriever as a microwire to guide a monorail angioplastic balloon to the extracranial carotid stenosis, performing angioplasty simultaneously with stent retriever anchorage. Clinical outcomes, procedural data, and safety were assessed. Results: Successful reperfusion (mTICI > 2b) was achieved in 91% of cases, with a median groin puncture to final recanalization time of 50 min. Favorable clinical outcomes (mRS < 3) were observed in 69% of patients, with a low mortality rate of 6% after 90 days. Conclusions: The T-Top technique offers a rapid and reliable strategy for TL treatment, improving reperfusion rates and clinical outcomes. Further studies are warranted to validate its efficacy in larger cohorts. This technique holds promise for enhancing endovascular treatment outcomes in patients with Tandem Lesions.

Keywords: endovascular neurosurgery; internal carotid artery (ICA) stenosis; middle cerebral artery (MCA) stenosis; new technique; stroke; tandem lesions; tandem occlusions.

Figure 1

An illustrative image of the ‘’T-Top technique’’. Left: For the first step, after the deployment of the stent retriever at the level of intracranial occlusion, a monorail balloon, fitted over the pusher wire of the stent retriever, is employed to perform an angioplasty maneuver to resolve the extracranial carotid lesion. Right: During the balloon’s deflation, an 0.88” long sheath extends over the stenosis, and it is possible to perform mechanical thrombectomy and solve the intracranial occlusion.

Figure 2

The roadmap from the CCA, 45–60° oblique projection. (a) A balloon angioplasty 0.018” monorail system (Sterling, Boston Scientific) is located at the level of the ICA stenosis (in this case, proximally to the origin) and (b) inflated. Note the control of the intracranial stent retriever’s position in the MCA during this maneuver. Black arrow: stent retriever deployment at the M1-M2 segment.

Figure 3

A roadmap from the CCA, 45–60°oblique projection. (a) During balloon deflation, the guide catheter is brought over the stenosis (red arrow). (b) The guide catheter in the final position after the complete deflation of the balloon catheter at the middle cervical segment of the ICA. Note the same position of the stent retriever (black arrow) after this passage.

Figure 4

(a) After the ‘’T-Top technique’’, the guide catheter is stable, and it is possible to perform mechanical thrombectomy to remove the intracranial clot with the stent retriever still in position at the M1-M2 segment. (b) An aspiration catheter (in this case, a 0.062″ inner lumen) is engaged with the proximal third of the stent retriever; then, a combined technique is performed to perform a mechanical thrombectomy. Orange arrow: the stent retriever at M1-M2; red circle: the aspiration catheter in front of the intracranial clot.

Figure 5

The 45–60°oblique projection. Right: The final result with the positioning of the carotid stent over a 0.014′ microwire, in order to completely treat the extracranial carotid lesion. Left: The final LL projection angiography shows a TICI 3.