Cartwright Michael S, Shin Hae W, Passmore Leah V, Walker Francis O
Department of Neurology, Wake Forest University School of Medicine, Medical Center Boulevard, Winston-Salem, North Carolina 27157, USA.
J Neuroimaging. 2009 Jan;19(1):47-51. doi: 10.1111/j.1552-6569.2008.00256.x. Epub 2008 May 8.
Several studies have evaluated the cross-sectional area of the median nerve at the wrist, but none have examined other sites along the median nerve. Nerve enlargement has been demonstrated in entrapment, hereditary and acquired neuropathies, as well as with intraneural masses, and cross-sectional area reference values at sites along the nerve will help in the evaluation of these conditions. In addition, muscle intrusion into the carpal tunnel has been implicated in carpal tunnel syndrome, but the normal amount of muscle intrusion has not been quantified.
Fifty asymptomatic volunteers (100 arms) were evaluated to determine the mean cross-sectional area of the median nerve at 6 sites and the mean amount of muscle intruding into the carpal tunnel.
The cross-sectional area of the nerve was consistent along its course (7.5 to 9.8 mm(2)). The amount of muscle within the carpal tunnel varied greatly, with the mean area of flexor digitorum being 15.5 mm(2) and lumbricals 13.5 mm(2).
These reference values are necessary for advancing the field of neuromuscular ultrasound, because they facilitate studies of the median nerve in conditions such as entrapment, hereditary neuropathy, acquired neuropathy, and intraneural masses.
多项研究评估了腕部正中神经的横截面积，但尚无研究对正中神经其他部位进行检查。在神经卡压、遗传性和获得性神经病变以及神经内肿物中均已证实存在神经增粗，而神经各部位的横截面积参考值将有助于对这些情况进行评估。此外，肌肉侵入腕管与腕管综合征有关，但正常的肌肉侵入量尚未量化。
对50名无症状志愿者（100只手臂）进行评估，以确定正中神经6个部位的平均横截面积以及侵入腕管的肌肉平均量。
神经横截面积在其走行过程中保持一致（7.5至9.8平方毫米）。腕管内的肌肉量差异很大，指浅屈肌的平均面积为15.5平方毫米，蚓状肌为13.5平方毫米。
这些参考值对于推动神经肌肉超声领域的发展是必要的，因为它们有助于对诸如神经卡压、遗传性神经病变、获得性神经病变和神经内肿物等情况下的正中神经进行研究。
