超音波ガイド下骨格筋生検手技による構造、機能、細胞、生化学的特性の測定

Human muscle biopsies are often required to study or diagnose diseases. However, traditional approaches are challenging due to limited sample size, quality, or patient discomfort. Fine-gauge needle biopsies (≥14-gauge), present an alternative but yield insufficient sample sizes for histology or function. Ultrasound guidance, coupled with vacuum-assisted, single needle-insertion multiple sampling addresses these challenges. In 19 healthy participants (mean age: 30.1±10 years, 42% male), 2-3 samples were collected from a single needle insertion into the vastus lateralis (VL) and tibialis anterior (TA). Summed VL and TA sample masses averaged 148±38mg and 166±64mg, with dimensions of 15.83±8 x 2.9±0.6mm ² (VL) and 15.07±7 x 3.1±0.9mm ² (TA). VL had a mean fiber cross-sectional area of 4,347±1,931µm ² , with 221±86 fibers quantified. Samples were of sufficient size and quality for thorough analyses from a single biopsy procedure, including mitochondrial respirometry, RT-PCR, collagen content, and biomechanical function. Fibers produced typical isometric stress values of 187kPa with a passive modulus of 239kPa (peak) and 79kPa (stress-relaxed). This procedure was well tolerated, with an average immediate pain rating of 1.5±1 (range:0-4, scale: 1-10) and 24-hour follow-up rating of 1.7±1 (range:0-4). This report describes an approach that yields high-quality muscle samples suitable for histological and biochemical analyses while minimizing discomfort.