Can 129Xe ventilation MRI guide personalisation of airway clearance regimens in children with Primary Ciliary Dyskinesia?

Children with Primary Ciliary Dyskinesia (PCD) use airway clearance techniques (ACT), but clinicians lack sensitive outcome methods to guide ACT personalisation. We explored if providing data from highly sensitive ¹²⁹Xe Ventilation MRI (¹²⁹Xe-MRI) influenced physiotherapists’ decision making. During cognitive task analysis interviews, physiotherapists were asked to “think aloud” their clinical decisions whilst reviewing the data of children with PCD under their care: routine clinical information; baseline structural MRI; ¹²⁹Xe-MRI data acquired pre, post-ACT and 4-hours post-ACT. 5 experienced physiotherapists from four NHS trusts reviewed data from a total of 19 children with PCD (age 5-17years). ¹²⁹Xe-MRI data aligned with the physiotherapists’ existing clinical impression for nine cases. In these reviews, the ¹²⁹Xe-MRI either confirmed the physiotherapists’ ACT regimen decision or led them to propose modifications. In ten cases ¹²⁹Xe-MRI either challenged the current clinical impression or ¹²⁹Xe-MRI findings differed from structural MRI findings. For these cases, the physiotherapist either: re-evaluated their clinical decisions and proposed ACT regimen modifications or; felt unsure what regimen changes to propose during the review, so planned to reassess the patient in light of the ¹²⁹Xe-MRI findings. Clinical review of ¹²⁹Xe-MRI led physiotherapists to propose ACT regimen changes in some children with PCD. In some cases, clinical re-assessment was warranted prior to making regimen modifications. ¹²⁹Xe-MRI provides an intuitive 3D lung ventilation image, which is sensitive to airways obstruction and can inform ACT regimen personalisation.