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Updated: Jun 24, 2026

Effects of Blast-induced Neurotrauma on Pressurized Rodent Middle Cerebral Arteries
Published on: April 1, 2019
TMS neuro-cardiovascular coupling in vascular compression cranial neuropathy
Adam Kirton1, Carolyn Gunraj, Robert Chen
1Division of Neurology, Alberta Children's Hospital, University of Calgary, Calgary, Alberta, Canada.
Background:
Neurovascular compression (NVC) may cause cranial mononeuropathy but lacks a definitive diagnostic investigation. We hypothesized that the arterial pressure wave (APW) would interact at the neurovascular interface in NVC to inhibit transmission of transcranial magnetic stimulation (TMS) stimuli to affected muscles.
Methods:
We report a novel neurophysiological method coupling cardiovascular physiology with TMS. The electrocardiogram (ECG) and arterial pressure wave (APW) were coupled to triggering of cortical TMS in a patient with NVC-induced spinal accessory (CNXI) mononeuropathy. Outcome measures included motor evoked potential (MEP) amplitudes and firing probabilities of normal and affected trapezieus (TPZ). Values at intervals in proximity to the APW (40/80/120/160 ms) were compared to baseline (800 ms) using ANOVA and student t-test.
Results:
Electrocardiogram triggered TMS of CNXI pathways with 100% reliability. MEP amplitudes were decreased in proximity to the APW, particularly at 120 ms (0.21-0.04 mV versus 0.39 +/- 0.10 mV, p=0.003). TPZ firing probabilities were similarly inhibited (43.8% versus 88.2%, p=0.009). No effect of APW proximity was observed on the unaffected side (p=0.868). Procedures were well tolerated.
Conclusions:
Vascular compression causes CNXI mononeuropathy. Transcranial magnetic stimulation-cardiovascular coupling may evaluate neurovascular junction interactions and non-invasively diagnose NVC.
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