103. Neuro-muscular ultrasound study in pediatric healthy subjects: Normative data

Neuromuscular ultrasound (NMUS) is a non-invasive, painless and inexpensive technique that quickly screen large areas of muscles but only few data are reported in literature about pediatric physiological muscular structural changes. We collected, by means of a NMUS Health-Technology-Assessment (HTA) study (approved by Local Ethic Committee), pediatric quantitative and qualitative normative data. By NMUS we have bilaterally studied Anterior-Tibial, Long-Toe-Extensor, Rectus-Vastus-Femoris, Forearm-Flexors, Biceps muscles, considering thickness, echogenicity, pennation in 100 healthy children (M49-F51; range 2–16, mean 10,44 years; shared in five-age-groups: (I) 2–5; (II) 6–8; (III) 9–11; (IV) 12–14; (V) 15–16 ys); in about half of them sural and/or ulnar/median perimeter and area were measured. The muscles of I–II were less echogenic than III–IV–V groups. The muscles’ thickness (MT) increased with age especially between IV and V groups. In groups I–II the females’ MT was smaller than the males’s one. MT, BMI, weight were in relationship. The nerves’ area increased from I to V group. During childhood the muscular echogenicity and thickness increased rapidly, the latter especially during the puberty. Also the nerves’ area increased with age. NMUS is a useful tool to know physiological structural changes that are crucial to correctly interpretate and guide electromyographic and neuroimaging evaluation in clinically heterogeneous pediatric neuromuscular diseases.