Volume 16 Supplement 1

1st Joint ANIRCEF-SISC Congress

Open Access

P043. Hyperechogenicity of the periaqueductal gray in chronic migraine and episodic migraine as a potential marker of progressive dysfunction: preliminary results with transcranial sonography

  • Elena Guaschino1, 2,
  • Natascia Ghiotto1, 2,
  • Cristina Tassorelli2, 3,
  • Vito Bitetto2,
  • Giuseppe Nappi2,
  • Arrigo Moglia1, 3,
  • Daniele Bosone1 and
  • Grazia Sances2Email author
The Journal of Headache and Pain201516(Suppl 1):A61

https://doi.org/10.1186/1129-2377-16-S1-A61

Published: 28 September 2015

Background

It is widely accepted that the brainstem plays a role in migraine pathophysiology. The periaqueductal gray matter (PAG) is a substantial component of the descending pain modulatory network. Previous MRI studies by Welch et al demonstrated that PAG iron levels are abnormally high both in episodic and chronic migraine, suggesting the hypothesis that iron accumulation may be a marker of progressive PAG dysfunction. The increase in iron levels can be investigated with transcranial sonography (TCS) because of heavy metal-induced hyperechogenicity.

Aim

The purpose of our study was to evaluate hyperechogenicity of PAG in patients with episodic migraine (EM) and in subjects with chronic migraine associated with medication-overuse headache (CM+MOH).

Methods

We evaluated 10 patients diagnosed with EM and 10 patients with CM+MOH: one patient from group 1 and one from group 2 were excluded because of unsonable transtemporal window. TCS was performed using Acuson Sequoia ultrasound machine with a 2-MHz transducer. The sonographic parameters were set according to standard literature criteria. Using the transtemporal approach, the midbrain and diencephalic examination planes were visualized in axial section. Echogenicities of raphe midbrain, substantia nigra and PAG, thalami, lentiform nucleus and head of the caudate nucleus were examined and graded as hyperechogenic. The maximal width of the frontal horns of the side ventricles and the minimal transverse diameter of the third ventricle were measured on a standardized diencephalic examination plane. Hyperechogenicity was considered as the visually rated intensity of the ultrasound signal increase compared to the surrounding brain tissue.

Results

PAG echogenicity was higher in patients with CM+MOH than in those with EM: 6/9 CM+MOH patients showed PAG hyperechogenicity, while only 1/9 in the EM group.

Conclusions

These preliminary findings suggest the occurrence of a progressive degeneration of PAG in migraine. The possibility to reliably detect it with TCS would provide a low-cost, harmless, widely available tool. Evaluation on a larger population is needed to confirm PAG dysfunction in chronic migraine and the reliability of TCS for screening purpose and to predict the evolution of the disease.

Written informed consent to publication was obtained from the patient(s).

Conflict of interest

None.

Authors’ Affiliations

(1)
Clinical Neurophysiology Unit, University of Pavia
(2)
Headache Science Centre, National Neurological Institute C. Mondino
(3)
Department of Brain and Behavioural Sciences, University of Pavia

Copyright

© Guaschino et al. 2015

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.