Computed tomography of blunt and penetrating diaphragmatic injury: sensitivity and inter-observer agreement of CT Signs

Diaphragmatic injury is an uncommon but clinically important entity in the setting of trauma. Computed tomography (CT) is widely used to evaluate hemodynamically stable trauma patients. While prior studies have identified CT signs of diaphragm injury in blunt or penetrating trauma, no study has directly compared signs across these two types of injuries. We identified patients with surgically proven diaphragm injuries who underwent CT at presentation. Three reviewers examined each for 12 signs of diaphragm injury, as well as for an overall impression of diaphragm injury. We reviewed a total of 84 patients (37 % blunt trauma, 63 % penetrating). The initial interpreting radiologists discovered 77 % of blunt and 47 % of penetrating injuries (p?=?0.01). We found that the majority of signs of diaphragmatic injury were split between those common in blunt trauma and those common in penetrating trauma, with minimal overlap. The presence of at least one blunt injury sign has 90 % sensitivity for diaphragm injury in blunt trauma; the presence of a wound tract traversing the diaphragm has 92 % sensitivity in penetrating trauma. Inter-observer reliability of these signs is also high (κ?>?0.65). Penetrating diaphragm injuries present a different spectrum of imaging findings from those in blunt trauma and are underdiagnosed at CT; looking for a wound tract traversing the diaphragm is highly sensitive for diaphragm injury in these cases. Signs of organ or diaphragm fragment displacement are sensitive for blunt diaphragm injuries, consistent with these injuries being caused by increased intra-abdominal pressure.     

创伤性膈疝32例分析

目的 总结创伤性膈疝(TDH)的临床特征和诊治方法,以减少工作中的失误.方法 回顾性分析1990年1月～2011年1月我院32例TDH的分期、损伤类型和部位、疝入器官、诊断和治疗方法等.结果 32例中,男性24例,女性8例;年龄16～89岁.钝性伤23例(71.9%),穿透伤6例 (18.8%),医源性损伤3例(9.4...     

Rupture of the right hemidiaphragm following blunt trauma: the use of ultrasound in diagnosis

Diaphragmatic rupture occurs in approximately 5% of patients who sustain multiple trauma and post-mortem studies suggest that right-sided rupture is more common than generally realized. Four cases of rupture of the right hemidiaphragm secondary to blunt trauma are presented. The chest radiographs were all similar, demonstrating a right sided fluid collection and right lower lobe consolidation in all patients. No patient had a pneumothorax. CT was useful only in retrospect, demonstrating a posterior eventration of the liver into the thorax in two patients. Ultrasound proved diagnostic in all cases demonstrating either the free edge of the diaphragm as a flap within the pleural fluid or the liver herniating into the thorax. The value of ultrasound as a simple, non-invasive and direct means of imaging the diaphragm is emphasized.     

Helical CT of diaphragmatic rupture caused by blunt trauma

OBJECTIVE: The purpose of this study was to determine the diagnostic sensitivity and specificity of helical CT with sagittal and coronal reformatted images in detecting diaphragmatic rupture after blunt trauma. MATERIALS AND METHODS: Chest and abdominal helical CT scans obtained in 41 patients with suspected diaphragmatic injury after major blunt trauma were reviewed by three observers who were unaware of surgical findings. Coronal and sagittal reformatted images were reviewed for each patient as well. Findings consistent with diaphragmatic injury, such as waistlike constriction of abdominal viscera (i.e., the "collar sign"), intrathoracic herniation of abdominal contents, and diaphragmatic discontinuity were recorded. Sensitivity and specificity of helical CT were calculated on the basis of surgical findings and clinical follow-up. RESULTS: Helical CT was performed preoperatively in 23 patients with diaphragmatic rupture (left, n = 17; right, n = 5; bilateral, n = 1). An additional 18 patients underwent helical CT to further evaluate suspicious findings seen on chest radiography at admission and were found to have an intact diaphragm. Sensitivity for detecting left-sided diaphragmatic rupture was 78% and specificity was 100%. Sensitivity for the detection of right-sided diaphragmatic rupture was 50% and specificity was 100%. The most common CT finding of diaphragmatic rupture was the collar sign, identified in 15 patients (sensitivity, 63%; specificity, 100%). Diaphragmatic discontinuity was seen in four patients. CONCLUSION: Helical CT, especially with the aid of reformatted images, is useful in the diagnosis of acute diaphragmatic rupture after blunt trauma. Helical CT can be used to detect 78% of left-sided and 50% of right-sided injuries.     

肾上腺创伤的CT表现

目的 探讨肾上腺损伤(AGT)的CT表现特征.方法 回顾性分析1712例因腹部钝伤行CT检查的患者中AGT患者的CT检查结果.结果 1712例中,共发现AGT 29例(1.7%),右侧损伤23例,左侧3例,双侧3例,共32个病灶.主要CT表现:(1)肾上腺血肿:22例25个病灶,呈孤立立圆形或卵圆形肿块,平扫为高密度或混杂密度,三期动态增强扫描均无强化,肿块周围见推移张开的肾上腺肢体,呈弧形线状明显强化.(2)肾上腺肿胀:4例,表现为受损部肾上腺肢体肿胀,体积增大.(3)肾上腺弥漫性出血:3例,肾上腺被出血包埋,正常肾上腺结构消失.1例伴对比剂外溢,手术证实为肾上腺碎裂伴活动性出血.伴随征象主要包括伤侧肾上腺周围条纹状出血浸润影,膈肌脚增粗等.合并其他胸腹部脏器损伤25例.结论 AGT具有特征性CT表现,采用合理扫描技术并正确认识AGT的CT征象有助于避免漏诊和误诊.     

The "dependent viscera" sign in CT diagnosis of blunt traumatic diaphragmatic rupture

OBJECTIVE: The objective of our study was to describe the "dependent viscera" sign and determine its usefulness at CT in the diagnosis of diaphragmatic rupture after blunt abdominal trauma. MATERIALS AND METHODS: The study sample consisted of 28 consecutive patients (19 men, nine women) between 17 and 74 years old (mean age, 31 years) who had undergone abdominal CT and subsequent emergency laparotomy after a blunt trauma. Ten patients had a diaphragmatic rupture (six, right-sided; four, left-sided) at laparotomy. An experienced radiologist unaware of the surgical findings retrospectively reviewed the CT scans, and then a second radiologist reviewed the scans to provide interobserver agreement. Note was made of discontinuity of the diaphragm, intrathoracic herniation of abdominal contents, and waistlike constriction of bowel (the collar sign). Also noted was whether the upper one third of the liver abutted the posterior right ribs or whether the bowel or stomach lay in contact with the posterior left ribs. Either of these findings was termed the "dependent viscera" sign. The radiologists' detection rate of diaphragmatic rupture on the CT scans via observance of the dependent viscera sign was determined. Interobserver agreement was assessed using Cohen's kappa statistic. RESULTS: The dependent viscera sign was observed on the CT scans of 100% of the patients with a left-sided diaphragmatic rupture and of 83% of the patients with right-sided diaphragmatic rupture. Both observers missed one case of right-sided diaphragmatic rupture. The radiologists' overall rate of detecting diaphragmatic rupture was 90% using the dependent viscera sign. We found excellent interobserver agreement (kappa = 1) for detection of the dependent viscera sign and for the diagnosis of diaphragmatic tear on CT scans. CONCLUSION: The dependent viscera sign increases the detection at CT of acute diaphragmatic rupture after blunt trauma.     

Helical CT of blunt diaphragmatic rupture

OBJECTIVE: This study evaluated CT findings for signs of blunt diaphragmatic rupture. MATERIALS AND METHODS: CT examinations of 179 blunt trauma patients, including 11 with left-sided and five with right-sided blunt diaphragmatic rupture, were reviewed by two staff radiologists who first decided by consensus on the presence or absence of 11 published signs of blunt diaphragmatic rupture and then formulated the diagnosis in terms of absence of, presence of, or suggestion of blunt diaphragmatic rupture. The significance of the findings was assessed by multivariate logistic regression. Four other reviewers interpreted the CT findings independently. They were asked first to formulate a diagnosis in terms of absence of, presence of, or suggestion of blunt diaphragmatic rupture and then to enumerate the findings supporting a diagnosis or suggestion of blunt diaphragmatic rupture. These findings were compared with those of the staff radiologists. RESULTS: Diaphragmatic discontinuity, diaphragmatic thickening, segmental nonrecognition of the diaphragm, intrathoracic herniation of abdominal viscera, elevation of the diaphragm, and both hemothorax and hemoperitoneum were strong predictors of blunt diaphragmatic rupture (p < 0.001). The combination of the first three findings was 100% sensitive (16/16). The staff radiologists' sensitivity for diagnosing blunt diaphragmatic rupture was 100% (16/16). The four reviewers' sensitivities were 56.2% (9/16), 81.2% (13/16), 62.5% (10/16), and 87.5% (14/16). CONCLUSION: Six of 11 signs were good predictors of blunt diaphragmatic rupture. Despite diaphragmatic thickening, focal defect and segmental nonrecognition had 100% cumulative sensitivity; the reviewers formulating the diagnosis before analyzing CT signs overlooked blunt diaphragmatic rupture on CT in 12.5-43.8% of the patients.     

Thoracic computed tomography in victims of blunt trauma: changes in utilization after the introduction of helical technology

Purpose: In blunt trauma, CT of the thorax is often performed because of the limitations of plain film chest radiography in accurately depicting injuries to the thoracic aorta. The advent of helical CT has allowed the entire chest to be imaged more expeditiously. We will evaluate the extent to which this ability to rapidly obtain additional images of the thorax has increased the utilization of chest CT in blunt trauma. Methods: The radiologic records of all victims of blunt trauma who underwent total body CT (TBCT), which included abdomen, pelvis, and chest images, in the 10 months before and 10 months after our institution acquired helical CT (HCT), were retrospectively evaluated. Results: In the 10 months before we obtained HCT, 520 conventional CT of the abdomen and pelvis were completed, of which only 11 (2.1 %) included images of the full thorax. After HCT was instituted, 684 abdomen and pelvis CT were performed, of which 59 (8.6 %) were ordered with the entire chest. Of the 11 conventional TBCT, 6 (55 %) showed findings in the chest; in 2 of these cases (18 %) the abnormalities were confined exclusively to the thorax. Similarly, of the 59 helical TBCT, 31 (53 %) depicted traumatic abnormalities in the thorax, and in 23 of these cases (39 %) injuries were only within the chest. In 4 of the latter the injuries were mediastinal hematomas, 1 of which (25 %) was confirmed angiographically to represent an aortic laceration. Conclusion: The speed and ease with which additional images can be obtained by HCT has greatly increased utilization of cross-sectional imaging of the thorax after blunt trauma (approximately four-fold). Over half of these depict traumatic injuries.     

46例钝性与穿透性膈肌损伤的临床比较研究

目的　分析比较钝性与穿透性膈肌损伤的临床特点和伤情,以指导创伤的救治。　方法　46例胸外伤合并膈肌破裂病人分为穿透伤组和钝性伤组,比较两组的损伤情况,并应用创伤评分系统进行创伤严重度评估。　结果　钝性胸外伤造成膈肌破裂的发生率低,复杂,常合并全身多发伤,但伤情进展相对较慢;穿透性胸外伤造成膈肌破裂的发生率高,伤情进展迅速,早期易出现失血性休克。比较损伤严重度评分(ISS)、修正创伤评分(RTS)和胸部简明损伤定级(AIS),两组间差异无统计学意义（P>0.05）,但钝性伤组入院时格拉斯哥昏迷指数(GCS)和腹部AIS较低,分别为12.69±2.69,1.62±1.66（P<0.05）。　结论　针对钝性与穿透性膈肌损伤的不同临床特点,应采取相应的治疗措施,减少并发症,改善预后。     

Frequency and importance of transverse process fractures in the lumbar vertebrae at helical abdominal CT in patients with trauma

PURPOSE: To evaluate the frequency and importance of transverse process fractures of lumbar vertebrae identified at helical computed tomography (CT) in patients with blunt abdominal trauma. MATERIALS AND METHODS: Helical abdominal CT scans in 536 consecutive patients with a history of blunt abdominal trauma were prospectively evaluated for transverse process fractures of the lumbar spine. The number and level of fractures were categorized and correlated to the retrospective and initial interpretations of the radiographs obtained at original trauma examination. Number and type of associated abdominal injuries were recorded. RESULTS: CT scans showed transverse process fractures in 39 (7.3%) patients. Seventy-nine fractures were identified (single fractures in 12 patients, multiple fractures in 27). Fractures were right-sided in 13 patients, left-sided in 24, and bilateral in two. Transverse process fractures of the L3 vertebra were most common (n = 25). Fractures were not reported in 20 (61%) of 33 initial radiographic assessments. Even at retrospective review, only 30 (57%) of 53 fractures were correctly identified. Transverse process fractures were associated with abdominal injuries in 20 (51%) patients; this association was statistically significant (P <.001). CONCLUSION: Initial conventional radiography is relatively insensitive in the detection of transverse process fractures of the lumbar spine. There is a statistically significant association between transverse process fractures and abdominal injury.     

MDCT diagnosis of penetrating diaphragm injury

The purpose of the study was to determine the diagnostic sensitivity and specificity of multidetector CT (MDCT) in detection of diaphragmatic injury following penetrating trauma. Chest and abdominal CT examinations performed preoperatively in 136 patients after penetrating trauma to the torso with injury trajectory in close proximity to the diaphragm were reviewed by radiologists unaware of surgical findings. Signs associated with diaphragmatic injuries in penetrating trauma were noted. These signs were correlated with surgical diagnoses, and their sensitivity and specificity in assisting the diagnosis were calculated. CT confirmed diaphragmatic injury in 41 of 47 injuries (sensitivity, 87.2%), and an intact diaphragm in 71 of 98 patients (specificity, 72.4%). The overall accuracy of MDCT was 77%. The most accurate sign helping the diagnosis was contiguous injury on either side of the diaphragm in single-entry penetrating trauma (sensitivity, 88%; specificity, 82%). Thus MDCT has high sensitivity and good specificity in detecting penetrating diaphragmatic injuries.     

Diaphragmatic rupture due to blunt trauma: sensitivity of plain chest radiographs

Preoperative diagnosis of diaphragmatic rupture caused by blunt injury is often difficult because of serious concurrent injuries, a lack of specific clinical signs, and simultaneous lung disease that may mask or mimic the diagnosis radiologically. Previous reports have suggested that a preoperative diagnosis is established on the basis of chest radiographs in only one third of patients. In order to assess the value of chest radiographs and other imaging techniques in diagnosing traumatic rupture of the diaphragm, we retrospectively reviewed all preoperative diagnostic imaging performed in 50 patients with surgically proved hemidiaphragmatic rupture due to blunt trauma. Chest radiographs were diagnostic in 20 (46%) of 44 patients with left-sided rupture and were considered suspicious enough to warrant further diagnostic studies in an additional eight patients (18%). Five patients with initially normal findings on chest radiographs had diagnostic findings on delayed chest radiographs. Chest radiographs were strongly suggestive in only one (17%) of six patients with right-sided hemidiaphragmatic rupture. CT was diagnostic for diaphragmatic rupture in only one (14%) of seven instances in which it was performed. MR was diagnostic in both patients in whom it was performed. Our experience indicates that chest radiographs obtained at admission and repeated soon after are more valuable in suggesting the diagnosis of traumatic rupture of the diaphragm than previously reported, particularly in the more frequent, left-sided injuries. This increased sensitivity may be due to a greater level of suspicion maintained in a trauma referral center in which this injury is not uncommon.     

创伤性膈肌破裂32例的临床诊断与治疗

目的探讨影响创伤性膈肌破裂临床诊断和治疗效果的因素。方法对本院收治的32例创伤性膈肌破裂患者的发病原因、部位、合并伤及损伤严重度评分、诊断经过及手术方法等分别进行分析。结果胸腹部开放性损伤为本组病人的主要损伤(75·0%),早期诊断或延迟诊断对病情的转归影响显著。合并伤的伤情严重度是决定患者死亡与否的重要因素之一。与早期确诊相比,延迟诊断病例的术后并发症增多,其发生率分别为5·3%与50·0%(P=0·072),平均住院时间分别为(9·6±1·5)d与(22·7±2·5)d,(P<0.01)。结论避免延迟诊断及选择正确的手术方法是提高抢救成功率的关键。     

CT manifestations of adrenal trauma: experience with 73 cases

Adrenal injuries, although an uncommon consequence of abdominal trauma, are important to recognize. If bilateral, adrenal trauma could result in life-threatening adrenal insufficiency. Furthermore, in the setting of trauma, adrenal injury can point to other concomitant injuries and has been associated with overall increased morbidity and mortality. In the past, before the advent of computed tomography (CT), detection was difficult, and the diagnosis was often made only at surgery or postmortem. Today, the diagnosis of adrenal injuries can be quickly and accurately made with CT. This retrospective review was carried out to identify, describe, and analyze different CT appearances of adrenal injuries and correlated with associated injuries and observed clinical context and outcomes. A patient cohort of CT-detected adrenal injuries was identified through a radiology software research tool by searching for keywords in radiology reports. The identified CT scans were reviewed and correlated with the patients’ available clinical chart data and follow-up. Between April 1995 and October 2004, 73 cases of CT-detected adrenal injuries were identified, including 48 men and 25 women, with an age range 6 to 90 years and a mean age of 42.7 years. Of the cases, 77% were right-sided, 15% were left-sided, and 8% were bilateral. The causes of injuries were motor vehicle collisions (75%), falls (14%), sports related (4%), and miscellaneous causes (7%). Associated trauma included injuries of the liver (43%), spleen (23%), lung (19%), and kidney (18%), as well as pneumothoraces/hemothoraces (22%). Skeletal injuries included fractures of the ribs, clavicles, and/or scapulae (39%), pelvis and hips (30%), and the spine (23%). Isolated adrenal trauma was seen in only 4% of the cases. The CT findings of adrenal trauma were focal hematoma (30%), indistinct (27%) or enlarged (18%) adrenal gland, gross (15%) or focal (7%) adrenal hemorrhage, and adrenal mass (11%). Associated CT findings included periadrenal fat stranding (93%), retroperitoneal hemorrhage (22%), and thickened diaphragmatic crura (10%). Active adrenal bleeding was seen in one case (1.4%). The incidence of adrenal trauma was estimated to be 0.86%. Surgical management was required only for the associated injuries. The most common CT manifestations of adrenal trauma include focal hematoma, indistinct or ill-defined adrenal gland, adrenal enlargement or mass, and gross or focal adrenal hemorrhage in a normal-sized gland. Periadrenal stranding is very common. Retroperitoneal hemorrhage and crural thickening are also important associated findings. Operative intervention is typically required only for the associated injuries, which commonly accompany adrenal trauma. This original research article was presented at RSNA 2005.     

Traumatic rupture of the right hemidiaphragm: Diagnosis by chest radiography

Sixteen cases of blunt trauma resulting in surgically confirmed traumatic rupture of the right hemidiaphragm were reviewed from the Trauma Registry of Allegheny General Hospital. Only 10 of the 16 cases (63%) could be retrospectively diagnosed on chest radiographs. We found that a diagnosis of right-sided diaphragmatic rupture can be suggested when the apex of the right hemidiaphragm is shifted superomedially to a position approximately midway between the mediastinum and the right chest wall. Eight of these 10 cases with positive chest radiographic findings exhibited this superomedial shift of the diaphragmatic apex. On initial assessment, without using this sign, 5 of these 10 cases were not diagnosed. We feel that the combination of elevation of the right hemidiaphragm in association with a medial shift of the apex of that diaphragmatic dome in a patient who has suffered extensive blunt thoracoabdominal trauma is strongly suggestive of traumatic rupture of the diaphragm.     

钝性与穿透性膈肌损伤临床比较研究

膈肌损伤约占创伤的5%～7%,由于腹部钝性暴力使腹内压瞬间急剧升高,下胸肋骨对膈肌的机械作用,以及穿透伤时锐器的直接损伤导致膈肌破裂,分为钝性与穿透性膈肌损伤.其早期诊断面临巨大挑战,而且其并发症和病死率高.手术前难以做准确诊断,成功处理有赖于对临床高度可疑者进行仔细的胸部X线、CT检查和尽早的手术探查.由于膈肌损伤机制不同,各有其临床特点和处理上的特殊性,本文就穿透性和钝性膈肌损伤的临床处理研究进展做一比较讨论,以期进一步提高膈肌损伤的救治水平.     

Imaging hemidiaphragmatic injury

The supine chest radiograph is the initial and most commonly performed imaging study to evaluate the thorax after trauma. Whenever the chest radiograph is equivocal or suspicious for acute diaphragmatic injury (DI), computed tomography (CT) is usually the next study of choice since it is both generally available and often used to examine other body regions in the patient after trauma. CT is usually diagnostic, particularly if supplemented by multiplanar reformation (MPR) obtained using thin-slice axial scanning and overlapping images for reformations. Magnetic resonance imaging (MRI) is potentially useful to assess the diaphragm if CT findings are indeterminate and the patient is stable enough to have the procedure. Simple T1-weighted spin-echo images in the sagittal and coronal orientation are usually sufficient to establish or exclude DI. This article reviews imaging modalities and strategies for diagnosing DI from blunt trauma.     

The dangling diaphragm sign: sensitivity and comparison with existing CT signs of blunt traumatic diaphragmatic rupture

The objectives of our study were to describe a new CT sign of diaphragmatic injury, the “dangling diaphragm” sign, and assess its comparative utility relative to other signs in the diagnosis of diaphragmatic injury resulting from blunt trauma. CT scans of 16 blunt trauma patients (12 men and four women, mean age 36.6 years old) with surgically proven diaphragmatic injury and 32 blunt trauma patients (24 men and eight women; mean age 37.4 years old) without evidence of diaphragmatic injury at surgery were blindly reviewed by three board certified radiologists specializing in body imaging. Studies were evaluated for the presence of established signs of diaphragmatic injury, as well as the dangling diaphragm sign, in which the free edge of the torn hemidiaphragm curls inward from its normal course parallel to the body wall. The sensitivity and specificity of each sign were determined, as were the correlation between the signs and the interobserver agreement in evaluation of these findings. The radiologists’ overall impression as to whether rupture was present was also recorded. In select cases, coronal and/or sagittal reformatted images were available, and they were reviewed following evaluation of the original axial images. Any change in interpretation due to these images was noted. The sensitivity of the radiologists’ overall impression for detection of diaphragmatic injury was 77%, with 98% specificity. Individual signs of diaphragmatic injury had sensitivities ranging from 44% to 69%, with specificities of 98% to 100%. The dangling diaphragm sign had a sensitivity of 54% and a specificity of 98%, similar to the other signs. Multiple signs were present in most cases of diaphragmatic injury, and coronal and sagittal reformatted images had little impact. Diaphragmatic injury remains a challenging radiographic diagnosis. The dangling diaphragm is a conspicuous sign of diaphragmatic injury, and awareness of it may increase detection of diaphragmatic injury on CT studies.     

Liver trauma due to penetrating lesions: miscellanea, personal case series, clinical and CT findings

PURPOSE: Penetrating liver wounds are related to many causes and rank second after blunt abdominal and liver trauma. We will report the clinical and radiological findings of our personal series of patients with penetrating trauma, especially by firearms and stab and cut wounds. We will also try to define the diagnostic workup of these traumas, which is especially based on CT signs of liver damage and associated changes and which is of basic importance for following treatment, both surgical or conservative. MATERIAL AND METHODS: In the last seven years we retrospectively reviewed 31 cases of penetrating liver trauma. The patients were 19 men and 12 women, ranging in age 18 to 73 (mean 42), with penetrating liver injuries from firearms (16 patients) and stab (9 cases) wounds; 6 patients had injuries from different causes. Abdominal CT was carried out in emergency with the CT Angiography (CTA) technique in all patients. In the patients with suspected chest and abdomen involvement CT was performed from the mid-chest for accurate assessment of diaphragm and lung bases and to exclude associated pleuropulmonary damage. RESULTS: Penetrating liver wounds were caused by firearms in 70% of cases, by stabbing in 12% and, in the extant 18%, by other causes such as home accidents, road and work traumas, and liver biopsy. In our series, the liver was most frequently involved, especially by firearms wounds; in our 16 cases the most frequent injuries were hemorrhagic tears. We found bullets in the liver in 6 cases. In one case of home accident the patient wounded himself while slicing bread with a long knife, which cut into the anterior abdominal wall and tore the anterior liver capsule, as seen at CTA. DISCUSSION AND CONCLUSIONS: Penetrating wounds to liver and abdomen are less frequent than those to the chest. In the past decade the use of CT has changed the diagnostic and therapeutic approach to such injuries completely, decreasing the resort to explorative laparotomy and hepatorrhaphy. Indeed, CT provides a clear picture of the extent and severity of damage, which permits to choose a conservative treatment in case of intraparenchymal hematomas and lacerocontusive foci without hemoperitoneum, which can be followed-up with physical and CT examinations. Moreover, Helical CT could provide the early diagnosis of active bleeding in the peritoneum and of focal bleeding in the liver, thus permitting prompt hepatorrhaphy or targeted hepatectomy. A diaphragm injury suspected at CT should always prompt the surgeon to intervention, especially when hemothorax, lung base pneumothorax, large liver hematoma or tear of the liver dome are associated. Finally, subdiaphragmatic free gas indicates gut perforation associated with liver damage, in which case surgery is necessary too.     

Penetrating trauma to the abdominal aorta: CT demonstration of active bleeding

Contrast-enhanced helical computed tomography (CT) is the imaging study of choice for evaluating the abdomen in hemodynamically stable patients following blunt trauma. Surviving victims of penetrating trauma, in contrast, are often hemodynamically unstable and may require urgent celiotomy with or without diagnostic peritoneal lavage (DPL) or ultrasonography. Abdominal CT is not routinely performed in this patient population, but may be done if the patient with penetrating abdominal trauma is stable on admission or becomes so with resuscitation. CT in this context can address questions regarding the location and extent of injury and help decide appropriate management. We present a case of a stabilized blunt and penetrating trauma patient with negative DPL and active retroperitoneal aortic extravasation demonstrated by CT. To our knowledge, penetrating injury to the aorta with active bleeding has not been previously seen on CT.