Aortic Injury and Hemopericardium: Key Findings and Evaluation

Abstract

Traumatic thoracic aortic injury and hemopericardium are among the most life-threatening conditions encountered in acute thoracic trauma care. CT angiography (CTA) is the cornerstone of evaluation in such cases, providing essential information for diagnosis, triage, and treatment planning. In traumatic aortic injury, key CTA findings, including the presence of an intimal flap, intramural hematoma, pseudoaneurysm, and contrast extravasation, form the basis of the Society for Vascular Surgery grading system and guide management. In patients with traumatic hemopericardium, CT attenuation characteristics, imaging features of cardiac tamponade, and associated cardiac injuries help determine the urgency and approach to intervention. Familiarity with common pitfalls and mimickers, including ductus diverticulum, mediastinal hematoma without aortic injury, and motion-related artifacts, is essential to avoid diagnostic errors. Structured reporting can facilitate communication of management-relevant findings and support timely decision-making. This review summarizes the imaging findings, grading systems, management implications, pitfalls, and structured reporting considerations for traumatic aortic injury and hemopericardium.

INTRODUCTION

Traumatic thoracic aortic injury and hemopericardium are among the most life-threatening conditions in acute thoracic trauma care (1,2). The clinical burden of these injuries is likely underestimated because many patients die before reaching the hospital, and even those who survive to initial evaluation may show rapid deterioration (1,2). Thoracic aortic injury may cause exsanguinating hemorrhage, whereas hemopericardium may progress to cardiac tamponade, causing abrupt circulatory collapse (1,2,3).

Imaging is central to both the initial triage and definitive management of such injuries. Portable chest radiography and Extended Focused Assessment with Sonography for Trauma (e-FAST) can provide rapid bedside screening, but neither modality can reliably exclude clinically significant cardiovascular injury in high-risk patients (4,5). When the patient is stable enough to undergo CT, CT angiography (CTA) is the first-line modality for definitive evaluation and has largely replaced catheter angiography (1,2,6,7). CTA can facilitate diagnosis as well as treatment planning by delineating the injury site, extent, severity, and associated thoracic findings (2,6,8). Clear reporting of these imaging findings is essential for timely clinical decision-making. However, despite the central role of imaging in this setting, previous reviews on this topic have mainly focused on describing imaging findings, whereas literature specifically addressing how imaging features influence triage, management decisions, and communication with the trauma team remains comparatively limited (6,8).

Accordingly, this review focuses on traumatic aortic injury and hemopericardium, emphasizing imaging findings that directly influence triage and management decisions. It also reviews common pitfalls and mimickers and proposes a practical structured reporting approach to support timely communication in acute thoracic trauma.

MECHANISMS OF INJURY

Recognition of the injury mechanisms can help radiologists anticipate the expected injury pattern and focus the evaluation on specific thoracic structures during CT interpretation (9). Information regarding the type of trauma (blunt or penetrating), the direction of impact, and the energy of the event can provide important clues for identifying patients at risk for thoracic vascular or cardiac injury (9).

BLUNT TRAUMA

In developed countries, blunt thoracic trauma is most commonly caused by motor vehicle collisions, which account for more than two-thirds of cases, followed by high-energy falls or direct chest impact (9,10). From a mechanistic perspective, blunt thoracic trauma can be broadly classified into rapid deceleration injury, compression/crush injury, and blast injury, with rapid deceleration representing the predominant mechanism underlying blunt traumatic aortic injury (BTAI) (6). These injury patterns generate various biomechanical forces on the thoracic aorta, including stretch, shear, pinch, and thump mechanisms (Fig. 1) (11). Stretch injury results from opposing longitudinal traction forces on the thoracic aorta, whereas shear injury develops at transition zones between mobile and fixed aortic segments, particularly at the aortic isthmus. Pinch injury reflects direct compression of the aorta between the sternum and vertebral column, while thump injury refers to abrupt intraluminal pressurization of the aortic blood column. These mechanisms frequently and collectively contribute to aortic disruption.

Fig. 1. Schematic illustration of the biomechanical mechanisms underlying blunt traumatic aortic injury.

The aortic isthmus is the most common site of injury because it is relatively fixed.

Stretch, shear, pinch, and thump forces may act individually or in combination and contribute to aortic disruption, particularly at the aortic isthmus.

The aortic isthmus near the ligamentum arteriosum is particularly vulnerable because it is tethered, whereas the proximal aorta remains comparatively mobile. Consequently, the most frequent site of injury is the aortic isthmus and the adjacent proximal descending thoracic aorta (Fig. 1), followed by the ascending aorta and aortic arch (6,12).

Blunt cardiac injury ranges from myocardial contusion, the most common manifestation, to rare but potentially fatal cardiac rupture (13). Injury mechanisms include direct precordial impact, cardiac compression between the sternum and thoracic spine, laceration from displaced rib or sternal fractures, and transmitted force from below the diaphragm (13). Because of its anterior position, the right ventricle is the chamber most frequently involved (14).

PENETRATING TRAUMA

Penetrating thoracic trauma may arise from gunshot wounds, stab injuries, or other sharp objects (15). Cardiac injury is common in patients with penetrating thoracic trauma and may manifest as myocardial laceration, hemopericardium, or cardiac tamponade, often leading to rapid hemodynamic deterioration (2,15). Similar to blunt cardiac injury, the right ventricle is most frequently involved because it lies closest to the anterior chest wall (16).

IMAGING EVALUATION

SCREENING IMAGING: CHEST RADIOGRAPHY AND e-FAST

Portable chest radiography, often combined with e-FAST, is useful for rapid bedside triage and early stabilization before CT acquisition (16,17,18). The National Emergency X-Radiography Utilization Study (NEXUS) suggests chest radiography when any of the following factors are present: age older than 60 years, a rapid deceleration mechanism, chest pain, intoxication, altered mental status, distracting painful injury, and chest wall tenderness (8). Portable chest radiography can identify associated thoracic injuries such as rib fractures, pulmonary contusion, pneumothorax, and hemothorax, but its ability to diagnose or exclude traumatic aortic injury is limited (8). Classic findings such as mediastinal widening, obscuration of the aortic contour, rightward tracheal deviation, and loss of the aortopulmonary window may raise suspicion for aortic injury (Fig. 2) (19,20). Chest radiography may also indicate pericardial effusion or tamponade through enlargement of the cardiac silhouette with or without an epicardial fat pad sign (3,21).

Fig. 2. Blunt traumatic rupture at the aortic isthmus in a 73-year-old woman after a motor vehicle collision.

A. A portable chest radiograph shows mediastinal widening, obscuration of the aortic contour, rightward tracheal deviation, and loss of the aortopulmonary window, raising suspicion for aortic injury. Diffuse haziness of the left lung field is also noted.

B, C. Axial CT angiographic images confirm active contrast extravasation from the aortic isthmus with associated contour abnormality (arrows), consistent with free aortic rupture. Associated mediastinal hematoma and left hemothorax are present.

e-FAST provides rapid bedside assessment without ionizing radiation and is particularly useful for detecting pericardial effusion, intrathoracic free fluid, and pneumothorax (18). In unstable patients with suspected hemopericardium or cardiac tamponade, the pericardial view of e-FAST can rapidly detect pericardial fluid and prompt urgent intervention (5,18).

However, both chest radiography and e-FAST have limited sensitivity for excluding thoracic vascular injury (4,19,21). Classic radiographic features such as mediastinal widening alone have a low positive predictive value, and normal findings on chest radiography or e-FAST do not exclude clinically significant aortic or pericardial injury (4,18,21,22). Therefore, when clinical suspicion persists, especially after high-risk mechanisms, definitive evaluation with CTA is warranted when permitted by the hemodynamic status (5,9,23).

CTA: PROTOCOL AND TECHNICAL CONSIDERATIONS

With the widespread availability of modern multidetector CT, CTA has largely replaced catheter angiography as the first-line imaging modality for suspected traumatic thoracic vascular and cardiac injuries (2,23,24,25). However, a universally accepted optimal trauma CTA protocol is lacking at present. Therefore, protocol selection should be individualized according to the clinical question, injury mechanism, patient hemodynamic status, and institutional workflow (2,26,27).

Despite this variability, a properly timed arterial-phase acquisition is essential when traumatic aortic injury is suspected (26,28). In patients with blunt thoracic trauma, dedicated chest CTA performed only in the arterial phase is often sufficient (2,26). In patients with polytrauma, chest CTA is frequently incorporated into whole-body CT protocols, wherein the chest is typically evaluated in the arterial phase while the abdomen and pelvis are commonly acquired in the portal venous phase to allow simultaneous assessment of vascular injury and solid organ trauma (5,26,27).

In penetrating thoracic trauma, patients frequently undergo monophasic imaging as part of rapid trauma CT evaluation. However, multiphasic imaging, including arterial and venous phases and occasionally delayed imaging, may improve sensitivity for major venous injury, active bleeding, or equivocal arterial-phase findings (28). Although electrocardiogram (ECG) gating is not mandatory in trauma imaging, it may be helpful when motion artifacts involving the aortic root or ascending aorta limit interpretation (Fig. 3) (1,21,26).

Fig. 3. Pulsation artifact at the ascending aorta in a 41-year-old man after a motor vehicle collision.

A. Initial non–ECG-gated axial CT angiographic image shows apparent bilateral pseudointimal flaps along the ascending aorta with blurred margins and no associated periaortic hematoma. Periaortic hematoma surrounding the descending thoracic aorta is also present.

B. ECG-gated axial CT angiographic image obtained 8 days later shows complete resolution of the finding, confirming a pulsation artifact. The periaortic hematoma surrounding the descending thoracic aorta has resolved. Bilateral pleural effusions have increased on the follow-up study.

ECG = electrocardiogram

After image acquisition, appropriate reconstruction and post-processing are essential for accurate evaluation of traumatic vascular injury. Thin-section reconstruction and multiplanar reformations should be routinely reviewed to improve the visualization of vascular injury and mediastinal structures. Advanced reconstruction techniques, including dual-energy CT-based images or metal artifact reduction, may be useful in selected problem-solving situations, but they are not routine components of trauma CTA protocols (2,29). In patients with renal dysfunction, no BTAI-specific CTA protocol has been established, and protocol selection should follow general iodinated contrast safety guidance with individualized risk-benefit assessment (30).

AORTIC INJURY

CT FINDINGS

On trauma CTA, direct imaging findings of traumatic aortic injury include intimal flap, pseudoaneurysm, intramural hematoma, focal contour abnormality (including abrupt caliber change), intraluminal filling defect (such as mural thrombus), and contrast extravasation (1,31,32,33). These findings have shown the highest diagnostic accuracy and interobserver agreement. Therefore, they should be prioritized during interpretation (34). Careful evaluation of arterial-phase images using multiplanar reconstructions—particularly sagittal reformations—is essential for detecting subtle abnormalities that may be inconspicuous on axial images alone (Fig. 4).

Fig. 4. Small pseudoaneurysm at the aortic isthmus with associated periaortic mediastinal hematoma in a 55-year-old man after a motor vehicle collision.

A. Pre-contrast axial CT image shows a small amount of hyperattenuating periaortic mediastinal hematoma around the aortic arch with loss of the normal periaortic fat plane (arrows).

B. Axial CT angiographic image demonstrates a subtle pseudoaneurysm at the aortic isthmus (arrowhead), representing the source of the mediastinal hematoma. Bilateral hemothoraces are also present.

C. Sagittal CT angiographic image clearly delineates the pseudoaneurysm at the aortic isthmus (arrowhead).

Indirect CT findings remain important when direct signs are subtle or imaging confidence is limited. The most significant indirect sign is periaortic mediastinal hematoma abutting the aorta with loss or displacement of the normal periaortic fat plane (32,34). Identification of mediastinal hematoma on non-contrast images, followed by careful assessment of the periaortic fat plane, may help localize a potential vascular source. Preservation of a clean periaortic fat plane reduces the likelihood of an aortic source, whereas periaortic involvement substantially increases suspicion for aortic injury (Fig. 4) (34). However, periaortic hemorrhage alone does not confirm luminal disruption, since it may reflect injury to the vasa vasorum or adjacent venous structures (32,34). Accordingly, indirect findings should prompt systematic segmental inspection for subtle direct signs rather than serve as standalone diagnostic criteria. Associated findings such as pleural effusion or hemothorax—more commonly left-sided—may provide supportive context but do not exclude aortic injury when absent (1,32). These CTA findings also form the basis of contemporary imaging-based grading systems for BTAI. Key CT findings for the diagnosis of traumatic aortic injury are summarized in Table 1.

Table 1. Diagnostic Checklist for Suspected Aortic and Pericardial Injuries.

Category		Key Findings
Aortic injury
	Direct signs	Intimal flap, intramural hematoma, pseudoaneurysm, focal contour abnormality, intraluminal filling defect, or active contrast extravasation
	Indirect signs	Periaortic mediastinal hematoma with loss or displacement of periaortic fat plane
Pericardial injury
	Pericardial fluid*	Simple effusion (<20 HU) Acute hemopericardium (30–45 HU) Clotted hemopericardium (50–100 HU) Active contrast extravasation (>180 HU)
	Suggestive findings of cardiac tamponade	Right atrial and ventricular compression, interventricular septal flattening or leftward bowing, enlarged superior vena cava, inferior vena cava, venous contrast reflux, hepatic and renal vein enlargement, or periportal edema

^*In the traumatic setting, however, any newly detected pericardial fluid should be presumed hemorrhagic until proven otherwise, even if attenuation values fall within the range of simple effusion. Also, these values should be interpreted in conjunction with clinical context, acquisition phase, and associated CT findings.

HU = Hounsfield unit

SVS GRADING

The Society for Vascular Surgery (SVS) grading system is the most widely used imaging-based classification for BTAI (35). Under this system, injuries are categorized into four grades: Grade 1, intimal tear; Grade 2, intramural hematoma; Grade 3, pseudoaneurysm; and Grade 4, free rupture (Fig. 5). Grade 1 and Grade 2 are generally considered to indicate lower-grade injuries, whereas Grade 3 and Grade 4 represent more advanced structural disruption associated with an increased risk of progression and mortality (24,35,36). In particular, Grade 4 injury corresponds to complete aortic rupture and carries an extremely high mortality rate, often because of early exsanguination after trauma (24,33). Given its simplicity and direct correlation with imaging findings, the SVS four-grade system remains the most widely used framework for standardized communication and management planning in contemporary practice.

Fig. 5. Representative axial CT angiographic images illustrating the Society for Vascular Surgery grading spectrum of blunt traumatic thoracic aortic injury.

A. Grade 1, intimal tear (arrow).

B. Grade 2, intramural hematoma (arrow).

C. Grade 3, pseudoaneurysm (arrow).

D. Grade 4, rupture with active contrast extravasation (arrow).

IMAGING-BASED MANAGEMENT STRATEGY

Definitive treatment is determined on the basis of the CTA-defined injury grade, anatomic suitability for repair, and competing traumatic priorities (6,24,35,36). According to the updated SVS guidelines, Grade 1 and Grade 2 injuries, collectively categorized as minimal aortic injuries, are generally managed with definitive nonoperative management. Routine surveillance imaging is not recommended for Grade 1 injuries, whereas Grade 2 injuries should undergo at least one follow-up CTA, typically within 1–3 months after injury, to confirm stability or resolution. For Grade 3 injuries, treatment should be individualized according to the hemodynamic status and the presence of associated traumatic injuries. In hemodynamically stable patients, delayed thoracic endovascular aortic repair (TEVAR) beyond 24 h may be considered to allow management of competing injuries, whereas urgent interventions are recommended when the aortic injury is believed to be the primary cause of hemodynamic instability. Grade 4 injuries require emergent repair because of the extremely high risk of exsanguination and death.

Current guidelines support an endovascular-first approach for most repairable descending thoracic aortic injuries when anatomically feasible (Fig. 6) (35,36,37,38,39). Therefore, CTA is essential not only for injury grading but also for procedural planning, including assessment of landing zones, arch anatomy, access vessels, and the potential need for left subclavian artery coverage. When left subclavian artery coverage is anticipated, factors such as vertebral-artery dominance, prior left internal mammary artery bypass grafting, and an anomalous vertebral-artery origin should be considered during multidisciplinary planning.

Fig. 6. Thoracic endovascular aortic repair for rupture of the descending thoracic aorta in a 79-year-old woman after a motor vehicle collision.

A, B. Axial and sagittal CT angiographic images show rupture (Society for Vascular Surgery Grade 4) of the descending thoracic aorta (arrows).

C. Follow-up sagittal CT angiographic image obtained after emergent thoracic endovascular aortic repair shows successful exclusion of the ruptured segment by the stent graft without residual contrast extravasation.

Anti-impulse therapy may be used as a stabilizing measure in selected patients, particularly those with Grade 3 injuries awaiting definitive repair. However, in patients with concomitant traumatic brain injury or other competing injuries, management should be individualized, and blood-pressure targets should be determined through multidisciplinary collaboration (35).

HEMOPERICARDIUM AND CARDIAC TAMPONADE

CT FINDINGS AND PATHOPHYSIOLOGY

CT attenuation measurement plays a central role in the characterization of pericardial fluid. Fluid attenuation near water density favors a simple serous effusion, whereas attenuation greater than water indicates hemopericardium or another complex etiology (3,21). In the acute trauma setting, however, any newly detected pericardial fluid in a patient with an appropriate mechanism of injury should be presumed to be hemorrhagic until proven otherwise (21). Acute hemorrhage typically measures approximately 30–45 Hounsfield units (HU), clotted blood shows measurements of 50–100 HU, and markedly high attenuation (>180 HU) suggests active contrast extravasation requiring urgent escalation (Fig. 7) (3,40). These attenuation values should be interpreted in conjunction with the clinical context, acquisition phase, and associated CT signs. Importantly, the absence of hyperattenuating pericardial fluid does not exclude clinically significant cardiac injury (21).

Fig. 7. Acute hemopericardium with active contrast extravasation and a focal right atrial laceration in an 80-year-old man following a motorcycle accident.

A. Pre-contrast axial CT image shows hyperattenuating pericardial fluid measuring approximately 35 HU, consistent with the findings for acute hemopericardium.

B. Axial CT angiographic image shows markedly hyperattenuating pericardial fluid measuring approximately 190 HU, consistent with active contrast extravasation (*). A focal wall defect is seen in the anterior wall of the right atrium at the level of the superior cavoatrial junction (arrow). Despite cardiopulmonary resuscitation, return of spontaneous circulation was not achieved.

HU = Hounsfield unit

Traumatic hemopericardium may result from cardiac laceration or rupture mainly involving the right atrium, right ventricle, and the superior cavoatrial junction, coronary or great vessel injury, or myocardial contusion following penetrating or blunt trauma (Fig. 7) (2,21,27). Accordingly, when hemopericardium is detected, evaluation for associated cardiac or vascular injury should be performed with attention to the previously described underlying injury mechanisms. Cardiac-chamber rupture contained within the pericardium may produce hemopericardium that progresses to tamponade, whereas concomitant pericardial disruption may decompress blood into the pleural or peritoneal space, resulting in minimal hemopericardium but potentially fatal exsanguination (21,41).

Cardiac tamponade is a life-threatening condition caused by accumulation of fluid, blood, gas, or tissue within the pericardial cavity, leading to increased intrapericardial pressure, impaired diastolic filling, reduced stroke volume, hypotension, and cardiogenic shock (3,42,43). Because the right-sided chambers are thinner and more compliant, they are typically affected first. The progressive pressure elevation eventually leads to equalization of diastolic pressures and declining cardiac output (3,42).

Although tamponade is primarily a clinical diagnosis, CT may provide the first objective evidence of physiologic compromise in patients with trauma (2,3). Tamponade should be suspected when a pericardial effusion—particularly one with high attenuation—is accompanied by cardiac compression and systemic venous congestion (2,3,40). CT findings may include right-sided chamber compression or contour straightening, interventricular septal straightening or leftward bowing, enlargement of the superior vena cava and inferior vena cava relative to the adjacent aorta, contrast reflux into the inferior vena cava or azygos vein, hepatic and renal vein enlargement, and periportal edema (Fig. 8) (3). Because individual findings lack specificity, interpretation should rely on the overall constellation of imaging findings rather than any single sign (2,3). Key CT findings for traumatic pericardial injury, including hemopericardium and cardiac tamponade, are summarized in Table 1.

Fig. 8. Acute hemopericardium with CT findings suggestive of cardiac tamponade in an 80-year-old woman after a motor vehicle collision.

A. Pre-contrast axial CT image shows hyperattenuating pericardial fluid measuring approximately 45 Hounsfield units, consistent with acute hemopericardium.

B, C. Axial CT angiographic images demonstrate distention of the inferior vena cava (arrow) and reflux into the hepatic veins (arrowhead), suggesting cardiac tamponade. Surgical findings confirmed a laceration at the superior cavoatrial junction that was not directly visualized on CT.

IMPLICATIONS FOR MANAGEMENT

Management of traumatic hemopericardium and cardiac tamponade should be guided primarily by the patient’s hemodynamic status and by imaging findings that suggest the nature of the pericardial collection (2,21,42,43). Patients with clinical tamponade require urgent pericardial decompression. In hemodynamically stable or temporarily stabilized patients, image-guided pericardiocentesis may be considered as the initial drainage strategy, with echocardiography generally preferred for procedural guidance (42,43). In patients with trauma, however, percutaneous drainage may be inadequate when imaging suggests clotted or loculated hemopericardium, ongoing bleeding, suspected cardiac laceration, or associated pericardial rupture with decompression into adjacent spaces. In such situations, surgical drainage or operative exploration is more appropriate (21,41,43). Therefore, imaging reports should describe not only the presence of pericardial fluid but also its attenuation, distribution, suspected clot burden, associated signs of tamponade, and any findings that favor operative rather than percutaneous management (2,24,43).

PITFALLS AND MIMICKERS

Accurate diagnosis of traumatic aortic and pericardial injuries requires familiarity with common imaging mimickers and technical artifacts that may lead to false-positive or false-negative interpretations (32,44). The aortic isthmus, the most frequent site of blunt aortic injury, is also the location where several anatomic variants and physiologic structures can simulate traumatic pathology.

DUCTUS DIVERTICULUM VERSUS TRAUMATIC PSEUDOANEURYSM

A ductus diverticulum at the aortic isthmus is one of the most common mimickers of traumatic pseudoaneurysm on CTA. It typically appears as a smooth focal bulge along the inner curvature just distal to the left subclavian artery origin and is characterized by a wide base, smooth margins, and obtuse angles between the outpouching and the aortic wall (Fig. 9). In contrast to traumatic pseudoaneurysms, a ductus diverticulum at the aortic isthmus usually lacks associated intimal disruption or periaortic mediastinal hematoma (32,45). Traumatic pseudoaneurysms more often demonstrate a narrow base, irregular or undercut margins, acute angles with the aortic wall, and supportive traumatic findings such as an intimal flap or mediastinal hematoma (Fig. 10) (32,44,45). However, because a diverticulum may occasionally form relatively acute angles, equivocal cases should be interpreted in the overall traumatic context rather than on morphology alone (32).

Fig. 9. Ductus diverticulum at the aortic isthmus in a 62-year-old woman.

Oblique sagittal CT angiographic image shows a smooth focal bulge (arrow) along the inner curvature of the aortic isthmus just distal to the left subclavian artery origin, with a wide base and obtuse angles with the aortic wall; these findings are consistent with a ductus diverticulum.

Fig. 10. Blunt traumatic pseudoaneurysm at the aortic isthmus in an 18-year-old man after a fall from the fourth floor.

A. Sagittal CT angiographic image demonstrates a pseudoaneurysm (Society for Vascular Surgery Grade 3, arrow) at the aortic isthmus with irregular margins and acute angles with the adjacent aortic wall.

B. Axial CT angiographic image shows the pseudoaneurysm (arrow) at the aortic isthmus with surrounding mediastinal hematoma (*). The associated right-sided pneumothorax, chest wall emphysema, and lung collapse are also present. Although delayed aortic repair was considered, the lesion remained stable with blood-pressure control on follow-up CT.

ATTRIBUTION OF MEDIASTINAL HEMATOMA

Attribution of mediastinal hematoma to the aorta requires caution (32,44). An isolated anterior mediastinal hematoma is unlikely to represent incomplete aortic injury and is more plausibly related to injury of the internal mammary or bronchial vessels, venous injury, or adjacent fractures (32). In contrast, a periaortic mediastinal hematoma that directly abuts the aorta and effaces the periaortic fat plane is an important indirect sign that should prompt careful reassessment for direct aortic injury (Fig. 4) (32,34). Nevertheless, such hematomas may arise from injury to the vasa vasorum or perivascular veins rather than true luminal rupture (32,34).

MOTION- AND ACQUISITION-RELATED ARTIFACTS

Motion-related artifacts are common on non–ECG-gated trauma CTA and may mimic intimal flaps or partial transection (32,44). Cardiac-pulsation artifacts often appear as bilateral pseudointimal flaps along the aortic wall, typically near the aortic root, and are characterized by blurred margins without associated periaortic hematoma (Fig. 3) (1,32). Respiratory-motion artifacts should be assessed on lung windows, which can help distinguish true pathology from artifacts. When necessary, ECG-gated CT may be performed to reduce cardiac-motion artifacts (1,44).

SUBTLE INJURY AND GRADING-RELATED PITFALLS

Minimal aortic injury, such as a Grade 1 intimal tear without external contour abnormality, can be inconspicuous on axial images alone. Thus, routine reviews using multiplanar reformatted planes—particularly sagittal reconstructions—can reduce both missed injuries and overcalls. Accurate grading is essential because minimal injuries may be managed conservatively in selected patients, underscoring the importance of distinguishing subtle intimal irregularities from artifacts (32).

MIMICKERS OUTSIDE THE AORTA

Structures outside the aorta may also simulate traumatic findings. Epicardial or pericardial fat can mimic pericardial fluid but demonstrates negative HU values on attenuation measurement (46). Fluid present within the pericardial recesses may resemble mediastinal lymph nodes or cystic lesions (47). Contrast–blood mixing may create apparent intraluminal filling defects that should not be misinterpreted as thrombus (32,44). Overall, the interpretation of suspected traumatic aortic or pericardial injuries should integrate morphologic features, associated traumatic findings, multiplanar assessment, and technical considerations (3,21,32). Reliance on a single imaging feature in isolation increases the risk of both overdiagnosis and missed injury (3,32).

STRUCTURED REPORTING FOR TRAUMATIC AORTIC AND PERICARDIAL INJURIES

In acute thoracic trauma, radiology reports must support rapid and reliable clinical decision-making. However, free-text reports may be inconsistently organized and are prone to omission of critical findings, potentially causing miscommunication in time-critical settings (48,49,50). Structured reporting can help standardize terminology and present management-relevant information in a clear format (49,50,51). Therefore, for traumatic aortic and pericardial injuries, reports should remain concise and indication-oriented while emphasizing key findings that directly influence management, including injury location and grade, presence of hemopericardium and CT features of tamponade, major associated thoracic injuries, and a clear impression that highlights management-relevant findings (49,51,52). Table 2 presents a practical structured report for CT in suspected traumatic aortic and pericardial injuries.

Table 2. Proposed Structured Report for Aortic and Pericardial Injuries.

Category	Findings
Aorta	□ Absent │ □ Present
	Location: □ Ascending aorta □ Aortic arch □ Descending thoracic aorta □ Abdominal aorta
	□ Blunt aortic injury	SVS grade: □ 1/□ 2/□ 3/□ 4
	□ Penetrating aortic injury
Pericardium	□ Absent │ □ Present
	□ Pericardial fluid	□ Simple effusion
		□ Hemopericardium
		□ Active contrast extravasation into the pericardium
	□ Suggestive findings of cardiac tamponade
	□ Associated pericardial injury	□ Pneumopericardium
		□ Pericardial rupture
	□ Associated cardiovascular injury	□ Myocardial contusion
		□ Cardiac laceration or rupture
		□ Coronary artery injury
		□ Non-aortic great vessel injury
Associated findings	□ Fracture
	□ Hemothorax
	□ Pneumothorax
	□ Pulmonary contusion
	□ Pulmonary laceration
	□ Other: __

Multiple selections are allowed when appropriate. Underlined blanks indicate free-text entries.

SVS = Society for Vascular Surgery

CONCLUSIONS

CTA is central to the evaluation of thoracic aortic and pericardial injuries in acute trauma. The radiology report should move beyond simple description and clearly characterize the suspected injury, including its anatomic extent and severity, to directly inform management. A structured and concise reporting approach can improve communication with the trauma team, clarify diagnostic uncertainty, and support timely triage and treatment in time-critical settings.

Supplementary Materials

Korean translation of this article is available with the Online-only Data Supplement at http://doi.org/10.3348/jksr.2026.0065.