- Email: [email protected]
Grade I traumatic aortic injury progression
Clinical Imaging 64 (2020) 50–52
Contents lists available at ScienceDirect
Clinical Imaging journal homepage: www.elsevier.com/locate/clinimag
Cardiothoracic Imaging
Grade I traumatic aortic injury progression☆ Luke Pecha, Barbara Pawley
T
⁎
University of Kentucky, Department of Radiology, 800 Rose Street, Room HX 313E, Lexington, KY 40356-0293, United States of America
ABSTRACT
This case highlights the importance of diagnosing Grade I aortic injuries after trauma. Although the prognosis for minimal aortic injury is typically quite good, the patient in this case suffered the unlikely complication of minimal intimal injury progression with resultant thromboembolism and massive stroke. Due to motion artifact and CT resolution limitations, the initial aortic injury was not detected. Thus, potentially life-saving measures such as serial CT monitoring of injury, blood pressure control, and endovascular repair were unable to be performed. This is a demonstration of the unfortunate complications of minimal aortic injury.
1. History The patient is a 51 year old man with a history of COPD who presented to the emergency department on October 1st, immediately after a motorcycle crash in which he was driving at 45–50 mph while intoxicated and not wearing a helmet. He was able to ambulate after the incident, reporting only a headache and a laceration above his eye; his physical exam was unremarkable and his vital signs were normal except for a BP of 167/103. The patient underwent a full body CT including CTA chest, which was read as normal except for motion artifact. He subsequently eloped from the ED against medical advice, having received no anticoagulation, blood pressure or heart rate control medications. Two weeks later, the patient returned to the ED, after he was found unresponsive at his home. His last known normal was two days prior to this admission. The patient failed to regain consciousness with a GCS score of 9, was not moving the right side of his body, and his eyes were deviated to the left. Another emergent full body CT was obtained, including CTAs of chest and neck. (At the first encounter, no CTA of head and neck was included in the evaluation but the carotid arteries are noted to be patent to the level of the lower cervical spine on that exam.) CTA findings indicated complete left common carotid artery occlusion and subsequent left MCA territory infarct with 3 mm midline shift. His aorta demonstrated a large intimal flap injury that was not appreciated at the patient's initial presentation. A retrospective look at the MIP sagittal image demonstrated motion artifact, which was reported, while
the axial image showed mild irregular thickening along the inferior medial wall of the mid arch that was not initially appreciated. The patient remained in the ICU with neurosurgical and neurology consults, and died three days later. 2. Findings 2.1. Initial presentation CTA chest (Fig. 1A) was unremarkable except for motion artifact, best appreciated on the sagittal MIP image of the aortic arch (Fig. 1B). Retrospectively, there was slight irregular thickening of the inferior medial aspect of the mid arch, consistent with subtle intimal injury (Fig. 1A). CT Head (not shown) showed no evidence of hemorrhage or ischemia. At the first encounter, no CTA of head and neck was included in the evaluation but the carotid arteries were noted to be patent to the level of the lower cervical spine (Fig. 1C). 2.2. Second presentation Axial CTA chest (Fig. 2A) showed a filling defect consistent with an aortic flap injury to the inferior aspect of the aortic arch at the level of the left common carotid artery. The flap is consistent with a Grade I aortic injury (intimal tear), as there is no evidence of pseudoaneurysm or rupture [1]. No hemothorax or extravasation of contrast is present. Coronal CTA (Fig. 2C) reveals a complete occlusion of the left
Minimal aortic injury progression. Corresponding author. E-mail address: [email protected] (B. Pawley).
☆ ⁎
https://doi.org/10.1016/j.clinimag.2020.03.008 Received 29 January 2020; Received in revised form 18 March 2020; Accepted 27 March 2020 0899-7071/ © 2020 Published by Elsevier Inc.
Clinical Imaging 64 (2020) 50–52
L. Pecha and B. Pawley
Fig. 1. A. Axial CTA image from initial presentation on October 1 was read as motion artifact but otherwise normal. In retrospect there is slightly thickened intimal irregularity vs thrombus (red arrow). B. Sagittal MIP image of the aortic arch documents the motion artifact with a dashed white arrow and shows the slightly thickened irregular intima in the inferior mid aortic arch. C. Two arrows demonstrate patent appearance of the proximal left carotid artery on the coronal reconstructed CTA of the aorta. A CTA of the neck was not obtained at the time of the initial presentation. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)
common carotid artery just distal to its origin above the level of the brachiocephalic vein; the thromboembolus most likely originated from the aortic flap and traveled to the left common carotid artery. Axial CTA of the neck (Fig. 2B) shows loss of visualization of the left common carotid artery; a large MCA-territory infarct with 3 mm midline shift is seen on the noncontrasted Head CT (Fig. 2D). 3. Discussion After high energy MVCs, blunt traumatic injury to the aorta is common and often fatal, with an over 80% initial mortality rate without intervention [2,3]. Wall damage, secondary to shearing, torsion, “Waterhammer,” and bending forces on the aorta, ranges from traumatic aortic ruptures visible on chest x-rays to intimal tears that can be undetectable even with CT. As per the Society for Vascular Surgery Guidelines, blunt aortic injuries are graded I-IV based on severity: Grade I is an intimal tear, Grade II an intramural hematoma, Grade III a pseudoaneurysm, and Grade IV a rupture. Minimal aortic injuries (MAI, or Grade I-II), defined as intimal tears < 1 cm and intramural hematomas, are commonly found after high-energy blunt trauma with advancing high-resolution CT imaging technology. These MAIs have the potential to progress to higher grades, or become nidi for thromboembolism, both of which were seen in this patient's case [4]. These traumatic minimal aortic injuries are well-established complications that have been noted since the landmark study by Parmley et al. in 1958, but large-scale studies are still lacking on the subject [2]. The largest study, by Osgood, et al. in 2014, followed all 42 instances of Grade I and II aortic injuries at their institution over ten years, and found that only 2 patients (5%) had progression to a higher grade while following them for an average of 74 days [5]. Of those without progression, 57% had complete resolution of their aortic injury. Though the quality of evidence is poor, it is important to note that the likelihood of progression is extremely low, and of those who progressed, neither patient died as a result of complications. This case highlights the importance of diagnosing Grade I aortic injuries after trauma. The patient in this case suffered the unlikely and dreaded complication of minimal intimal injury progression with resultant thromboembolism and massive stroke. Due to motion artifact and CT resolution limitations, the initial aortic injury was not detected. Thus, potentially life-saving measures such as serial CT monitoring of injury, blood pressure control, and endovascular repair, as were used in the Osgood study, were unable to be performed. Although the prognosis for minimal aortic injuries is quite good, it is critical that they be monitored through imaging to ensure that proper treatment can be given to those whose intimal injuries progress. Declaration of competing interest The authors declare that they have no conflict of interest.
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Clinical Imaging 64 (2020) 50–52
L. Pecha and B. Pawley
Fig. 2. A. At second presentation on October 18, a flapping intimal tear is seen in the aortic arch (red arrow). B. Axial CTA of the neck reveals a left common carotid artery that is not visualized due to thrombosis (yellow arrow). C. Coronal CTA of the chest shows the thromboembolus occluding the left common and internal carotid artery (red arrow). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.) D. Axial CT Head without contrast shows large left MCA-territory infarct (star), and midline shift.
References
[3] Groskin SA. Selected topic in chest trauma. Radiology 1992;183:605–17. [4] Creasy JD, Chiles C, Routh WD, Dyer RB. Overview of traumatic injury of the thoracic aorta. Radiographics 1997;17:27–45. [5] Osgood MJ, Heck JM, Rellinger EJ, et al. Natural history of grade I-II blunt traumatic aortic injury presenting over 10 years at a single institution. J Vasc Surg 2014;59(2):334–41.
[1] Lee WA, et al. Endovascular repair of traumatic thoracic aortic injury: clinical practice guidelines of the Society for Vascular Surgery. J Vasc Surg 2011;53(1):187–92. [2] Parmley LF, Mattingly TW, Manion WC, Jahnke Jr. EJ. Nonpenetrating traumatic injury of the aorta. Circulation 1958;17:1086–101.
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Contents lists available at ScienceDirect
Clinical Imaging journal homepage: www.elsevier.com/locate/clinimag
Cardiothoracic Imaging
Grade I traumatic aortic injury progression☆ Luke Pecha, Barbara Pawley
T
⁎
University of Kentucky, Department of Radiology, 800 Rose Street, Room HX 313E, Lexington, KY 40356-0293, United States of America
ABSTRACT
This case highlights the importance of diagnosing Grade I aortic injuries after trauma. Although the prognosis for minimal aortic injury is typically quite good, the patient in this case suffered the unlikely complication of minimal intimal injury progression with resultant thromboembolism and massive stroke. Due to motion artifact and CT resolution limitations, the initial aortic injury was not detected. Thus, potentially life-saving measures such as serial CT monitoring of injury, blood pressure control, and endovascular repair were unable to be performed. This is a demonstration of the unfortunate complications of minimal aortic injury.
1. History The patient is a 51 year old man with a history of COPD who presented to the emergency department on October 1st, immediately after a motorcycle crash in which he was driving at 45–50 mph while intoxicated and not wearing a helmet. He was able to ambulate after the incident, reporting only a headache and a laceration above his eye; his physical exam was unremarkable and his vital signs were normal except for a BP of 167/103. The patient underwent a full body CT including CTA chest, which was read as normal except for motion artifact. He subsequently eloped from the ED against medical advice, having received no anticoagulation, blood pressure or heart rate control medications. Two weeks later, the patient returned to the ED, after he was found unresponsive at his home. His last known normal was two days prior to this admission. The patient failed to regain consciousness with a GCS score of 9, was not moving the right side of his body, and his eyes were deviated to the left. Another emergent full body CT was obtained, including CTAs of chest and neck. (At the first encounter, no CTA of head and neck was included in the evaluation but the carotid arteries are noted to be patent to the level of the lower cervical spine on that exam.) CTA findings indicated complete left common carotid artery occlusion and subsequent left MCA territory infarct with 3 mm midline shift. His aorta demonstrated a large intimal flap injury that was not appreciated at the patient's initial presentation. A retrospective look at the MIP sagittal image demonstrated motion artifact, which was reported, while
the axial image showed mild irregular thickening along the inferior medial wall of the mid arch that was not initially appreciated. The patient remained in the ICU with neurosurgical and neurology consults, and died three days later. 2. Findings 2.1. Initial presentation CTA chest (Fig. 1A) was unremarkable except for motion artifact, best appreciated on the sagittal MIP image of the aortic arch (Fig. 1B). Retrospectively, there was slight irregular thickening of the inferior medial aspect of the mid arch, consistent with subtle intimal injury (Fig. 1A). CT Head (not shown) showed no evidence of hemorrhage or ischemia. At the first encounter, no CTA of head and neck was included in the evaluation but the carotid arteries were noted to be patent to the level of the lower cervical spine (Fig. 1C). 2.2. Second presentation Axial CTA chest (Fig. 2A) showed a filling defect consistent with an aortic flap injury to the inferior aspect of the aortic arch at the level of the left common carotid artery. The flap is consistent with a Grade I aortic injury (intimal tear), as there is no evidence of pseudoaneurysm or rupture [1]. No hemothorax or extravasation of contrast is present. Coronal CTA (Fig. 2C) reveals a complete occlusion of the left
Minimal aortic injury progression. Corresponding author. E-mail address: [email protected] (B. Pawley).
☆ ⁎
https://doi.org/10.1016/j.clinimag.2020.03.008 Received 29 January 2020; Received in revised form 18 March 2020; Accepted 27 March 2020 0899-7071/ © 2020 Published by Elsevier Inc.
Clinical Imaging 64 (2020) 50–52
L. Pecha and B. Pawley
Fig. 1. A. Axial CTA image from initial presentation on October 1 was read as motion artifact but otherwise normal. In retrospect there is slightly thickened intimal irregularity vs thrombus (red arrow). B. Sagittal MIP image of the aortic arch documents the motion artifact with a dashed white arrow and shows the slightly thickened irregular intima in the inferior mid aortic arch. C. Two arrows demonstrate patent appearance of the proximal left carotid artery on the coronal reconstructed CTA of the aorta. A CTA of the neck was not obtained at the time of the initial presentation. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)
common carotid artery just distal to its origin above the level of the brachiocephalic vein; the thromboembolus most likely originated from the aortic flap and traveled to the left common carotid artery. Axial CTA of the neck (Fig. 2B) shows loss of visualization of the left common carotid artery; a large MCA-territory infarct with 3 mm midline shift is seen on the noncontrasted Head CT (Fig. 2D). 3. Discussion After high energy MVCs, blunt traumatic injury to the aorta is common and often fatal, with an over 80% initial mortality rate without intervention [2,3]. Wall damage, secondary to shearing, torsion, “Waterhammer,” and bending forces on the aorta, ranges from traumatic aortic ruptures visible on chest x-rays to intimal tears that can be undetectable even with CT. As per the Society for Vascular Surgery Guidelines, blunt aortic injuries are graded I-IV based on severity: Grade I is an intimal tear, Grade II an intramural hematoma, Grade III a pseudoaneurysm, and Grade IV a rupture. Minimal aortic injuries (MAI, or Grade I-II), defined as intimal tears < 1 cm and intramural hematomas, are commonly found after high-energy blunt trauma with advancing high-resolution CT imaging technology. These MAIs have the potential to progress to higher grades, or become nidi for thromboembolism, both of which were seen in this patient's case [4]. These traumatic minimal aortic injuries are well-established complications that have been noted since the landmark study by Parmley et al. in 1958, but large-scale studies are still lacking on the subject [2]. The largest study, by Osgood, et al. in 2014, followed all 42 instances of Grade I and II aortic injuries at their institution over ten years, and found that only 2 patients (5%) had progression to a higher grade while following them for an average of 74 days [5]. Of those without progression, 57% had complete resolution of their aortic injury. Though the quality of evidence is poor, it is important to note that the likelihood of progression is extremely low, and of those who progressed, neither patient died as a result of complications. This case highlights the importance of diagnosing Grade I aortic injuries after trauma. The patient in this case suffered the unlikely and dreaded complication of minimal intimal injury progression with resultant thromboembolism and massive stroke. Due to motion artifact and CT resolution limitations, the initial aortic injury was not detected. Thus, potentially life-saving measures such as serial CT monitoring of injury, blood pressure control, and endovascular repair, as were used in the Osgood study, were unable to be performed. Although the prognosis for minimal aortic injuries is quite good, it is critical that they be monitored through imaging to ensure that proper treatment can be given to those whose intimal injuries progress. Declaration of competing interest The authors declare that they have no conflict of interest.
51
Clinical Imaging 64 (2020) 50–52
L. Pecha and B. Pawley
Fig. 2. A. At second presentation on October 18, a flapping intimal tear is seen in the aortic arch (red arrow). B. Axial CTA of the neck reveals a left common carotid artery that is not visualized due to thrombosis (yellow arrow). C. Coronal CTA of the chest shows the thromboembolus occluding the left common and internal carotid artery (red arrow). (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.) D. Axial CT Head without contrast shows large left MCA-territory infarct (star), and midline shift.
References
[3] Groskin SA. Selected topic in chest trauma. Radiology 1992;183:605–17. [4] Creasy JD, Chiles C, Routh WD, Dyer RB. Overview of traumatic injury of the thoracic aorta. Radiographics 1997;17:27–45. [5] Osgood MJ, Heck JM, Rellinger EJ, et al. Natural history of grade I-II blunt traumatic aortic injury presenting over 10 years at a single institution. J Vasc Surg 2014;59(2):334–41.
[1] Lee WA, et al. Endovascular repair of traumatic thoracic aortic injury: clinical practice guidelines of the Society for Vascular Surgery. J Vasc Surg 2011;53(1):187–92. [2] Parmley LF, Mattingly TW, Manion WC, Jahnke Jr. EJ. Nonpenetrating traumatic injury of the aorta. Circulation 1958;17:1086–101.
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