来院時のCTで図１〜図２１に遊離ガスを認めないが，消化管損傷を示唆する4つの所見がある．１：図２〜図１１の空腸▲は壁肥厚を呈している．２：図１７〜図２１の骨盤腔内に腹水がある（白矢印）．３：図１２〜図１６の左側腹膜が造影され（△）腹膜炎を示唆する．４：図１６の小腸↑は麻痺性イレウスの可能性が高い．従って5時間後に再検査を行い，早期診断につとめ，受傷後8時間以内に手術できるよう努力すべきである．最下段の図A〜図Dは8時間後のCT．遊離ガスが出現し（↑），腹膜炎の所見が明白になり（△），小腸間に液貯留を認め（※），骨盤腔の腹水は増量し（白矢印）消化管穿孔の所見がそろった．3時間前に撮影しておれば同様な所見で消化管穿孔の診断がついたと確信する．手術でTreitz靱帯から15cmの部位で3cm大の穿孔と，腸液による腹膜炎を認めた．

文献考察：seat belt （mark） sign（シートベルトの位置に一致する皮下斑状出血ecchymosis）があると消化管損傷が多い
１）Am Surg. 1999 Feb;65(2):181-5.
The "seat belt mark" sign: a call for increased vigilance among physicians treating victims of motor vehicle accidents.
Velmahos GC, Tatevossian R, Demetriades D.

The use of seat belts is shown to cause a specific pattern of internal injuries. Skin bruise corresponding to the site of the seat belt is known as the "seat belt mark" (SBM) sign and is associated with a high incidence of significant organ injuries. No study has yet defined the exact incidence of injuries requiring intervention at the presence of this sign. The objective of this study was to find the incidence of surgically correctable injuries in belted car occupants with a SBM sign and to define strategies of early detection and treatment of such injuries. The prospective study included consecutive patients involved in road traffic accidents who were admitted at an academic Level I trauma center. Of 650 car occupants, 410 (63%) were restrained and 77 (12%) had a SBM across the abdomen, chest or neck. The injuries of these 77 patients were compared with the injuries of belted patients without an SBM sign. Of patients with SBMs, 9 per cent had neck bruises, 32 per cent had chest bruises, 40 per cent had abdominal bruises, and 19 per cent had bruises in multiple sites. No significant neck injuries were detected. Three patients were found to have myocardial contusion, and 10 patients had intra-abdominal injuries (predominantly bowel and mesenteric lacerations) requiring laparotomy. There was a near 4-fold increase in thoracic trauma (22.5% versus 6%; P=0.01) and a near 8-fold increase in intra-abdominal trauma (23% versus 3%; P
２）Emerg Med (Fremantle). 2001 Mar;13(1):61-5.
Abdominal injury and the seat-belt sign.
Wotherspoon S, Chu K, Brown AF.

OBJECTIVE: To report on: 1. Prevalence of seat-belt sign in motor vehicle accident victims with abdominal injuries; 2. Prevalence of intestinal injuries in patients with seat-belt sign; and 3. Spectrum of abdominal injuries in a population with high usage of three-point restraints. METHODS: A retrospective chart review was conducted in an adult tertiary-referral hospital from January 1992 to August 1998. Patients were identified from International Classification of Disease-9 codes for abdominal wall and intra-abdominal injuries. RESULTS: The seat-belt sign was present in 60/99. The proportion of intestinal injuries in patients with and without seat-belt sign were 9/60 and 0/39, respectively (P = 0.01). In the 25 patients with intra-abdominal injuries, there were 10 hepatic, 8 splenic, 9 intestinal and 4 retroperitoneal injuries. CONCLUSION: The seat-belt sign is indicative of an increased risk of intestinal injury, which is difficult to detect with no single test providing reliable diagnosis. Other intra-abdominal and retroperitoneal injuries may also occur, which are more readily diagnosed on computed tomography scan or focused abdominal utlrasound when available, but are no more frequent in patients with the seat-belt sign than those without.　PMID: 11476415