Magnetic resonance imaging of the upper airways in children

Pediatric laryngeal stenosis (LTS) has various congenital and acquired causes.
Open airway surgery, through laryngotracheal reconstruction or cricotracheal
resection, is done to repair the airway without tracheostomy, while maintaining
swallowing and vocal function. Although the rate of successful surgical
interventions has improved over the last decades, sequelae, such as respiratory
complaints and dysphonia, are not uncommon. Anatomical and functional risk
factors leading to these sequelae are not well understood. Imaging of the
larynx post- surgery is likely to improve our understanding of these
pathophysiological risk factors. The development of Magnetic Resonance Imaging
(MRI), as an ionizing radiation- free alternative to Computer Tomography,
provides opportunities for safe morphological and functional imaging of the
upper airway in these children.

The overall aim of the study is to correlate the anatomical and functional
anatomy of the larynx, as seen on MRI to various functional outcome measures in
patients who underwent open airway surgery for LTS. The specific aims of this
study are: 1) to correlate anatomical changes related to surgery, as seen on
MRI, to clinical outcome, 2) to correlate the extent and location of fibrosis,
as seen on MRI, to clinical outcome and 3) to correlate dynamical vocal cord
function, as seen on MRI, to dysphonia. We hypothesize that MRI can be used as
an imaging technique, without the need for sedation and without the exposition
to ionizing- radiation, for extensive morphological and dynamic evaluation of
the pediatric larynx.

This study is a prospective cross- sectional study performed at the Erasmus MC-
Sophia Children*s Hospital in Rotterdam, the Netherlands.

Participation in this study will consist of a four hour visit to the Sophia
Children*s Hospital. The visit will consist of filling in questionnaires and
recording medical history (30 minutes), physical examination (10 minutes),
spirometry (30 minutes), vocal test (20 minutes), visit mock MRI (25 minutes)
and MRI (30- 45 minutes). None of these procedures are associated with a direct
risk for the patient. MRI is a radiation free technique without risk for the
children. The only adverse effect is related to the noisy and restricted
environment of the MRI scanner that can induce claustrophobia. Appropriate
training will be performed to avoid this adverse effect, and each subject will
have the opportunity to withdraw from the study at any moment. The main benefit
for this group of children will be a better understanding of anatomical and
functional risk factors related to adverse outcome post-open airway surgery. A
better understanding of these factors will improve the healthcare for this
patient group, the better quantification of post- surgical anatomical changes
will help develop future interventions and will allow for the development of
tailored management programs according to the specific morphological and/or
functional deficit. In addition, the further developed MRI of the pediatric
larynx, could replace potentially harmful current imaging methods.