Evaluation of hemodynamic impairments in unilateral high-grade carotid artery stenosis patients and healthy age-matched participants


Evaluation of hemodynamic impairments in unilateral high-grade carotid artery stenosis patients and healthy age-matched participants

Kaczmarz, S.; Göttler, J.; Griese, V.; Petr, J.; Zimmer, C.; Sorg, C.; Preibisch, C.

Objectives:

Internal carotid-artery stenosis (ICAS) is a major public health issue, as it accounts for approximately 20% of all strokes1. However, related complex hemodynamic impairments are not well understood2. We therefore propose a multimodal MRI-protocol. The major aims were to evaluate its reliability and investigate physiological changes.
Methods:
In the ongoing clinical study, 52 subjects (29 healthy controls: 70.3±4.7y, 13 males; 23 patients with asymptomatic unilateral ICAS, NASCET>70%: 70.5±6.8y, 15 males) underwent MRI on a Philips 3T-Ingenia. We propose a combination of three different MR-based methods, accounting for cerebrovascular reactivity (CVR) by breathhold-fMRI (voxelsize 3x3x3mm3, 38 slices, TE/TR=30ms/1200ms, acq.time=5:48min), CBF by pCASL (3D-readout, voxelsize 2.7x2.8x6mm3, 16 slices, TE/TR=7.4ms/4403ms, label duration=1800ms, PLD=2000ms, acq.time 5:43min) and relative oxygen extraction fraction (rOEF) by a multi-parametric quantitative-BOLD approach3 (voxelsize 2x2x3mm3, 30 slices). For each participant, individual masks of watershed areas were defined for both hemispheres in grey-matter and mean values of all three modalities were compared.
Results:
In healthy participants, our results show no significant lateralization of all three modalities on a group level. For ICAS-patients, regionally reduced CVR (p=0.003) as well as hypoperfusion (p< 0.001) were found ipsilateral to the stenosis (figure). In accordance with the literature, we did not find ICAS-induced changes in oxygen extraction on a group level (p=0.310).4 Even though focal rOEF increases could be suspected in single patients.
Conclusions:
The presented preliminary results thus imply successful application of our multimodal-MRI approach and are highly promising with respect to gaining a deeper insight into ICAS-related physiological changes. Further investigations of the relations between the parameters are currently in progress.

  • Open Access Logo Contribution to proceedings
    28rd International Symposium on Cerebral Blood Flow, Metabolism and Function, 01.04.2017, Berlin, Germany
    Proceedings of the 28rd International Symposium on Cerebral Blood Flow, Metabolism and Function, 498
  • Poster
    28rd International Symposium on Cerebral Blood Flow, Metabolism and Function, 01.04.2017, Berlin, Germany

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Publ.-Id: 25394