# Prognostic value of intracranial vascular tortuosity in thrombectomy for distal vessel occlusion

## TL;DR

This study finds that vascular tortuosity in the brain is linked to worse outcomes in stroke patients undergoing thrombectomy for medium/distal vessel occlusions.

## Contribution

The study introduces a method to automatically evaluate vascular anatomy as a potential predictor for thrombectomy outcomes in stroke patients.

## Key findings

- Increased tortuosity of the middle cerebral artery and internal carotid artery is associated with lower success rates in thrombectomy.
- Larger vessel diameter at the occlusion site correlates with increased risk of symptomatic intracranial hemorrhage.
- Anatomical features like bending length and mean diameter can predict both efficacy and safety of thrombectomy.

## Abstract

Neutral results from trials assessing mechanical thrombectomy (MT) for medium/distal vessel occlusions (MDVO) suggest the need for better selection criteria in these patients. Tortuous vascular anatomies may negatively influence MT efficacy and safety.

Consecutive patients with middle cerebral artery (MCA)-MDVO (M2/M3) who underwent MT at our center between January 2017 and September 2024 were included. Baseline CTAs were semi-automatically analyzed using an in-house vascular analysis framework. The internal carotid artery (ICA) tortuosity index (TI) and anatomical features of the MCA were extracted. Logistic regression adjusted for intravenous thrombolysis administration and onset-to-puncture time evaluated associations of anatomical features with treatment efficacy and safety endpoints. Primary endpoints were complete recanalization (final eTICI 2c/3) and symptomatic intracranial hemorrhage (sICH).

213 patients (81 years IQR 72–87, 51.2% female) were included. MCA bending length (aOR 0.48 [95%CI 0.27–0.86], p = 0.013), MCA-TI (aOR 0.77 [0.60–0.98], p = 0.032) and ICA-TI (aOR 0.59 [0.36–0.96], p = 0.034) were associated with lower probability of complete recanalization. ICA-TI (aOR 0.51 [0.31–0.84], p = 0.008) and mean MCA diameter (aOR 0.34 [0.13–0.90], p = 0.030) correlated with decreased odds of first-pass recanalization. Large mean MCA diameter was associated with lower likelihood of excellent functional outcome (aOR 0.30 [0.09–0.96], p = 0.042). Regarding safety endpoints, larger diameter at occlusion was associated with sICH (aOR 4.04 [1.03–15.87], p = 0.046), while MCA bending length (aOR 2.47 [1.24–4.92], p = 0.010) was linked to subarachnoid hemorrhage.

Automatic evaluation of anatomical vascular features may predict safety and efficacy of MT in stroke patients with MCA-MDVO. The value of these features as inclusion criteria for future MCA-MDVO clinical trials should be explored.

Intracranial vascular tortuosity is associated to poor thrombectomy outcomes in patients with MDVO.

Graphical abstract