Ultrasound assessment of the diaphragm: Preliminary study of a canine model of X-linked myotubular myopathy.

INTRODUCTION

We tested the feasibility of using neuromuscular ultrasound for non-invasive real-time assessment of diaphragmatic structure and function in a canine model of X-linked myotubular myopathy (XLMTM).

METHODS

Ultrasound images in 3 dogs [wild-type (WT), n=1; XLMTM untreated, n=1; XLMTM post-AAV8-mediated MTM1 gene replacement, n=1] were analyzed for diaphragm thickness, change in thickness with respiration, muscle echogenicity, and diaphragm excursion amplitude during spontaneous breathing.

RESULTS

Quantitative parameters of diaphragm structure were different among the animals. WT diaphragm was thicker and less echogenic than the XLMTM control, whereas the diaphragm measurements of the MTM1-treated XLMTM dog were comparable to those of the WT dog.

CONCLUSIONS

This pilot study demonstrates the feasibility of using ultrasound for quantitative assessment of the diaphragm in a canine model. In the future, ultrasonography may replace invasive measures of diaphragm function in canine models and in humans for non-invasive respiratory monitoring and evaluation of neuromuscular disease.