CAJ | 학술논문

目的　分析前臂肌群急性高压电击伤的MRI表现，并探讨其临床意义。方法　9例 17只急性高压电击伤的前臂均于72 h内行术前MRI检查，并作病理对照。7例14只前臂并行增强扫描。结果　9例 17只前臂均于MRI检查后立即行筋膜切开扩创术。单纯扩创者6例 11只前臂，MRI表现主要为前群肌肉的损伤，范围较小，呈等T1、长T2信号；后群肌肉损伤较分散，无一定规律，损伤程度较轻，病灶近端增强后和T2WI均示边界锐利，呈刀尖样改变；其中4例8只做了增强扫描，见显著异常强化(Ⅰ型信号)，术中电灼刺激相应肌肉有收缩，但较正常减弱，病理见不同程度坏死；在增强4例8只前臂中，有1个移行区者6只，有2个移行区者2只，各移行区边界均较清楚。扩创后截肢者3例 6只前臂，MRI表现为弥漫性前后群肌的损伤，呈混合信号，前臂近端以Ⅰ型信号为主，远端大片呈等T1、长T2或短T2信号，且无明显异常强化(Ⅱ、Ⅲ型信号)，术中电灼刺激相应肌肉，未见明确收缩，病理提示几乎完全坏死。所有截肢前臂均有2个移行区，边界不清，第2移行区均呈花边状强化。结论　前臂肌群急性高压电击伤MRI表现为3种信号模式，与病理有明确对应关系，有助于临床处理及预后判断。
목적　분석전비기군급성고압전격상적MRI표현，병탐토기림상의의。방법　9례 17지급성고압전격상적전비균우72 h내행술전MRI검사，병작병리대조。7례14지전비병행증강소묘。결과　9례 17지전비균우MRI검사후립즉행근막절개확창술。단순확창자6례 11지전비，MRI표현주요위전군기육적손상，범위교소，정등T1、장T2신호；후군기육손상교분산，무일정규률，손상정도교경，병조근단증강후화T2WI균시변계예리，정도첨양개변；기중4례8지주료증강소묘，견현저이상강화(Ⅰ형신호)，술중전작자격상응기육유수축，단교정상감약，병리견불동정도배사；재증강4례8지전비중，유1개이행구자6지，유2개이행구자2지，각이행구변계균교청초。확창후절지자3례 6지전비，MRI표현위미만성전후군기적손상，정혼합신호，전비근단이Ⅰ형신호위주，원단대편정등T1、장T2혹단T2신호，차무명현이상강화(Ⅱ、Ⅲ형신호)，술중전작자격상응기육，미견명학수축，병리제시궤호완전배사。소유절지전비균유2개이행구，변계불청，제2이행구균정화변상강화。결론　전비기군급성고압전격상MRI표현위3충신호모식，여병리유명학대응관계，유조우림상처리급예후판단。
Objective　To investigate the features of MR imaging of acute high-voltage electric injury in forearm muscle. Methods　Nine patients (17 forearms, 8 males and 1 female, 15～36 years of age) with clinically and pathological proved acute high-voltage electric injury were studied on MRI retrospectively. MRI studies were obtained within 72 hours on Siemens 1.0 T MR scanner. 2 forearms were examined with body coil, and 15 with head coil. The severe area was placed as near as possible to the isocenter in the magnet and was used as the center of the MR imaging acquisition. Spin-echo T1 weighted images, spin-echo and fast spin-echo T2 weighted images were acquired in all patients. 14 out of 17 were performed with Ⅳ administration of Gd-DTPA. Results　All 17 forearms had fascistomy after MRI. 11 had only debridement. The lesions were mainly observed in the flexor digitorum supericialis or profunduds muscle appearing as isointense on T1 weighted images, hyperintense on T2 weighted images, and strongly enhanced after Ⅳ administration of Gd-DTPA in 8. The proximal aspect of the lesion appeared as sharp-knife in 11. There was a weaker twitch response to electrocauterization in the injury muscle than in healthy muscle. It was variably necrotic in histopathology. Two transitional zones accompanied with the suffered forearm in 2, and one transitional zone in 6. Both of them had well-defined margin. 6 forearms had amputation after debriding. There was Ⅰ，Ⅱ，and Ⅲ mixture signal all over the forearms. The proximal lesions showed type Ⅰ changes. Distal to the zone of forearm showed type Ⅱ and Ⅲ pattern appearing as isointense on T1 weighted images, hyperintense and hypointense on T2 weighted images. It was hardly enhanced after Ⅳ administration of Gd-DTPA. There was no twitch response to electrocauterization in the injury muscle. It was almost completely necrotic in histopathology. ALL amputated forearms had two transitional zones and ill-defined margin. The second transitional zone was enhanced something like flower border. Conclusion　MR imaging of acute high-voltage electric injury in forearm appeared as three kinds of signal mode, which was closely related with histopathology. MRI was useful in dealing with clinic problem and in judging the prognosis.