Non-invasive, multimodal analysis of cortical activity, blood volume and neurovascular coupling in infantile spasms using EEG-fNIRS monitoring

Neuroimage Clin. 2017 May 13:15:359-366. doi: 10.1016/j.nicl.2017.05.004. eCollection 2017.

Abstract

Although infantile spasms can be caused by a variety of etiologies, the clinical features are stereotypical. The neuronal and vascular mechanisms that contribute to the emergence of infantile spasms are not well understood. We performed a multimodal study by simultaneously recording electroencephalogram and functional Near-infrared spectroscopy in an intentionally heterogeneous population of six children with spasms in clusters. Regardless of the etiology, spasms were accompanied by two phases of hemodynamic changes; an initial change in the cerebral blood volume (simultaneously with each spasm) followed by a neurovascular coupling in all children except for the one with a large porencephalic cyst. Changes in cerebral blood volume, like the neurovascular coupling, occurred over frontal areas in all patients regardless of any brain damage suggesting a diffuse hemodynamic cortical response. The simultaneous motor activation and changes in cerebral blood volume might result from the involvement of the brainstem. The inconstant neurovascular coupling phase suggests a diffuse activation of the brain likely resulting too from the brainstem involvement that might trigger diffuse changes in cortical excitability.

Keywords: Cerebral blood volume; EEG, electroencephalogram/electroencephalography; EMG, electromyography; Electroencephalography; HRF, hemodynamic response function; Hb, deoxyhemoglobin; HbO, oxyhemoglobin; HbT, total hemoglobin; Infantile spasm; NVC, neurovascular coupling; Neurovascular coupling; Optical imaging; PET, positron emission tomography; SPECT, Single photon emission computed tomography; TFR, time frequency representation; fNIRS, functional near infrared spectroscopy.

MeSH terms

  • Cerebral Cortex / diagnostic imaging
  • Cerebral Cortex / physiopathology*
  • Electroencephalography / methods*
  • Electromyography
  • Female
  • Humans
  • Infant
  • Male
  • Multimodal Imaging
  • Neurovascular Coupling / physiology*
  • Spasms, Infantile / diagnostic imaging
  • Spasms, Infantile / physiopathology*
  • Spectroscopy, Near-Infrared / methods*