Periodic paralysis (PP) is an ultra-rare muscle channelopathy characterized by episodes of transient, sometimes prolonged, motor deficits. British researchers conducted a muscle imaging study of the lower limbs of 45 patients diagnosed with PP:
- 17 patients had a mutation in a calcium channel gene, 16 in a sodium channel gene and 12 in a potassium channel gene,
- more than two-thirds had residual muscle weakness, and 20% were wheelchair-bound,
- Imaging revealed, even in paucisymptomatic patients, fatty infiltration in certain muscles, with a slightly different profile depending on the gene involved.
Although correlations between these images and other clinical parameters are tenuous, they will be useful in future therapeutic trials.
