Acute, Blood, Trauma /ecr2015/C-2116

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1 The Baltimore CT Severity Index (CTSI) versus the American Association of Surgical Trauma (AAST) for grading splenic Injury on CT: Use and implications of an imaging based grading system for splenic injury Poster No.: C-2116 Congress: ECR 2015 Type: Educational Exhibit Authors: A. Baghdanian, A. Baghdanian, C. Lebedis, S. Anderson, J. A. Soto; Boston, MA/US Keywords: Intraoperative, Embolisation, Catheter arteriography, CTAngiography, CT, Spleen, Emergency, Abdomen, Complications, Acute, Blood, Trauma DOI: /ecr2015/C-2116 Any information contained in this pdf file is automatically generated from digital material submitted to EPOS by third parties in the form of scientific presentations. References to any names, marks, products, or services of third parties or hypertext links to thirdparty sites or information are provided solely as a convenience to you and do not in any way constitute or imply ECR's endorsement, sponsorship or recommendation of the third party, information, product or service. ECR is not responsible for the content of these pages and does not make any representations regarding the content or accuracy of material in this file. As per copyright regulations, any unauthorised use of the material or parts thereof as well as commercial reproduction or multiple distribution by any traditional or electronically based reproduction/publication method ist strictly prohibited. You agree to defend, indemnify, and hold ECR harmless from and against any and all claims, damages, costs, and expenses, including attorneys' fees, arising from or related to your use of these pages. Please note: Links to movies, ppt slideshows and any other multimedia files are not available in the pdf version of presentations. Page 1 of 20

2 Learning objectives Review the etiology, natural history, and treatment of splenic injury. Compare and contrast the Baltimore CT Severity Index (CTSI) with the American Association for Surgical Trauma (AAST) for grading of splenic injury. Discuss the clinical implications of an imaging based grading system and how it can effect patient management. Background The spleen is the most commonly injured organ in abdominopelvic trauma. The most common cause in the United States is blunt trauma as a result of a motor vehicle collision (MVC) or a traumatic fall. Prompt diagnosis and management of splenic injury has significantly reduced the morbidity and mortality in this patient population. In early years, the extent of visceral or vascular injury was predominately based on a surgeon's clinical discretion and splenectomy was routinely performed. Over time the advent and increased prevalence of Multi-Detector CT (MDCT) and its use with optimized contrast enhanced multi-phase imaging protocols initiated a paradigm shift. The better characterization of splenic injury with the use of imaging has lead to the increased nonoperative management (NOM) of patients with the use of less invasive techniques such as splenic artery embolization (SAE) and advanced intensive care life support. The use and indications for SAE for splenic trauma vary between different institutions with no current gold standard in the management of hemodynamically stable patients. SAE is used as an alternative to laparotomy in patients with contraindications to surgery or in hemodynamically patients with vascular injury. The potential benefits of SAE include reduced complications, a shorter hospital course, and potentially preserved splenic immune function. Historically grading of splenic injury has been performed with the American Association for the Surgery of Trauma grading scale (2) that is based on gross anatomic findings of injury intra-operatively (AAST, Table 1). Page 2 of 20

3 Table 1 However, with the increased role of MDCT in characterizing the severity and extent of splenic injury, the need for an image based grading system has become essential. In 2007 Marmery et al. (1) introduced the Baltimore CT Severity Index (CTSI, Table 2) that supplemented the AAST scale with additional imaging based findings that helped characterize and risk stratify patients with splenic injury. Page 3 of 20

4 Table 2 The use of contrast enhanced multi-phase MDCT examinations has given us the ability to identify and characterize vascular injury. However the AAST grading system does not incorporate the full spectrum of vascular injuries or active hemorrhage, and several studies had shown the presence of these factors to be predictive of NOM failure (31, 32). Despite these issues the AAST scale is still used frequently in the literature for categorizing injury severity and dictating appropriate management (5-9). Comparing the two scales side by side (Figure 1), the CTSI includes a broader scope of vascular injuries that may change patient management or require additional patient interventions. Page 4 of 20

5 Fig. 1 Intraparenchymal vascular injuries such as pseudoaneurysm, arteriovenous fistula, and active intraparenchymal bleeding are classified as Grade 4a (Table 2). Extraparenchymal vascular injury such as active intra-peritoneal bleeding is classified as Grade 4b (Table 2). The major advantage of the CTSI is that it allows for direct correlation of MDCT imaging characteristics and choice of patient clinical management with resultant outcomes. In cases of blunt splenic injury this can include the risk of rebleeding, formation of abdominal abscesses, pseudoanuerysms, and overall mortality. Therefore it is better equipped to distinguish when a patient needs angio-intervention or surgery. It also can provide a uniform imaging based grading system used by radiologists that has been shown to have superior inter-observer reliability (1, 10). Page 5 of 20

6 Images for this section: Table 1 Page 6 of 20

7 Findings and procedure details The level 1 Trauma Registry Database at Boston University Medical Center was queried for patients with blunt splenic injury diagnosed on MDCT that underwent a SAE before any operative intervention. From there were 432 patients with blunt splenic injury of which 202 patients had an intervention in the form of surgery or embolization therapy. Of these 202 patients, 25 patients were evaluated that underwent SAE as their primary intervention. One investigator reviewed medical records to determine details of the hospital course and patient demographics. At Boston University Medical Center, patients presenting with blunt abdominal trauma and possible splenic injury undergo a designated MDCT multi-phase protocol that includes arterial, portal venous, and delayed phase acquisitions. At a majority of emergency imaging centers the abdominopelvic CT is obtained in the portal venous phase for assessment of visceral organ injury. We have found inclusion of an arterial phase has increased our sensitivity for detecting vascular injuries such as pseudoaneurysms and has allowed us to better characterize vascular splenic injury (11). Figure 2 demonstrates the multiphase CT of a 58 year-old male that fell from a height of 15ft. The patient was found to have two foci of active extravasation and was designated with CTSI Grade 4b injury. Fig. 2: Two foci of active extravasation (white arrows). Figure 3 below demonstrates the angiography of the same patient above that had successful coil embolization of two foci of active extravasation. Page 7 of 20

8 Fig. 3: Foci of active extravasation (black arrows) that were successfully treated with coil embolization (white arrows). Figure 4 demonstates the multiphase CT of a 55 year-old male that was in a large motor vehicle collison (MVC). The patient was found to have multiple foci of active extravasation. In the image below one of the foci is demonstrated that was most notable on the Portal Venous phase. This patient was designated with CTSI Grade 4b injury. Fig. 4: Focus of active extravasation (white arrow) in the spleen most notable in the Portal Venous and Delay Phases. Additional foci of active extravasation were seen in the spleen that are not included in this figure but can be seen on angiography images in Figure 5. Figure 5 below demonstrates the subsequent angiography of the above patient that had successful coil embolization of multiple foci of active extravasation. Page 8 of 20

9 Fig. 5: Focus of active extravasation (black arrow) with successful coil embolization (white arrow). Additional foci of active extravasation (curved black arrows) with successful coil embolization (curved white arrow). Figure 6 below demonstrates the multiphase CT of a 25 year-old male with blunt trauma after a physical assault. The patient was found to have two arterial enhancing foci with reduced contrast attenuation in the Portal Venous phase and resolution of contrast attenuation in the Delay phase, consistant with pseudoaneurysms and therefore CTSI Grade 4a injury. Inclusion of an arterial phase increases sensitivty of accurately diagnosing pseudoaneurysms as they have greatest contrast attenuation in the arterial phase seen in the image below. Page 9 of 20

10 Fig. 6: Two splenic pseudoaneurysms (white arrows). Figure 7 below demonstrates the angiography of the above patient that demonstrates delayed emptying of two arterialy enhancing pseudoaneurysms. Fig. 7: Two splenic pseudoaneurysms (black arrows). Figure 8 below demonstrates the multiphase CT and angiography of a 58 year-old male with splenic trauma after a MVC. The patient was found to have a focus of active extravasation and was successfuly treated with coil embolizaiton. The patient was designated with CTSI Grade 4b injury. Page 10 of 20

11 Fig. 8: CT images display a focus of active extravasation (white arrows). Angiography images demonstrate the same focus (Black arrows) that was successfully treated with coil embolization (curved black arrow). Figure 9 below demonstrates the repeat angiography of the above patient two weeks after his initial embolization. The patient was found to have two pseudoaneurysms that were new from prior examinations. The patient was designated as a failed SAE as primary therapy and subsequently underwent a a successful splenectomy. Fig. 9: Repeat angiography demonstrates two new foci with arterial enhancement and delayed emptying of contrast consistent with pseudoaneurysms (black arrows). Figure 10 below demonstrates a multiphase CT of a 28 year-old male with blunt trauma from a MVC. The patient was found to have active intraparenchymal hemorrhage and designated with a CTSI Grade 4a injury. Page 11 of 20

12 Fig. 10: Focus of active intraparenchymal hemorrhage (white arrows). Figure 11 below demonstrates angoigraphy of the above patient with active extravasation. The patient was successfuly treated with gel foam embolization. Of note, post-treatment images are not included below. Fig. 11: Focus of active intraparenchymal hemorrhage (Black arrows). Page 12 of 20

13 A two-tailed fisher's exact t-test was used to determine if there was a correlation between CTSI grade score and failed SAE as primary therapy. A failed outcome was defined as the need for splenectomy despite SAE. The results of our evaluation are displayed in Table 3 and Table 4 that demonstrate a successful outcome in a majority of our patients (21/25) despite a high CTSI grade score (grade 4a or 4b). The utility of the CTSI in predicting a failed outcome was not statistically significant (p>0.05) due to the unexpected high proportion of successful outcomes. However there was a statistically significant reduction in hospital stay (P<0.02) in patients that had a successful SAE (11 days) in comparison to patients that underwent splenectomy (22 days). Table 3 below demonstrates that a majority of patients were male with no significant difference in patient age. Table 3 Page 13 of 20

14 Two other blinded fellowship trained abdominal radiologists reviewed CT images and assigned a CTSI grade that is displayed below in Table 4. Table 4 The purpose of our evaluation was to determine if the CT Severity Index, or Baltimore CT grading system, accurately predicts the need for subsequent splenectomy in patients who undergo splenic artery embolization as the primary therapy for severe blunt splenic injuries. During the course of these investigations it became clear that this classification system does not reliably conclude when a splenectomy will inevitably follow primary embolic therapy. As seen in Table 4 above, while 8% of patients with grade 2 to 4a splenic injuries failed angioembolization compared to 23% of patients with grade 4b, this relationship was not statistically significant (p > 0.05). In other words, the severity of splenic insult does not Page 14 of 20

15 correlate with the need for operative intervention and that higher grade injuries do not mandate surgical management. Images for this section: Fig. 2: Two foci of active extravasation (white arrows). Fig. 3: Foci of active extravasation (black arrows) that were successfully treated with coil embolization (white arrows). Page 15 of 20

16 Fig. 4: Focus of active extravasation (white arrow) in the spleen most notable in the Portal Venous and Delay Phases. Additional foci of active extravasation were seen in the spleen that are not included in this figure but can be seen on angiography images in Figure 5. Fig. 5: Focus of active extravasation (black arrow) with successful coil embolization (white arrow). Additional foci of active extravasation (curved black arrows) with successful coil embolization (curved white arrow). Page 16 of 20

17 Fig. 6: Two splenic pseudoaneurysms (white arrows). Fig. 7: Two splenic pseudoaneurysms (black arrows). Fig. 8: CT images display a focus of active extravasation (white arrows). Angiography images demonstrate the same focus (Black arrows) that was successfully treated with coil embolization (curved black arrow). Fig. 9: Repeat angiography demonstrates two new foci with arterial enhancement and delayed emptying of contrast consistent with pseudoaneurysms (black arrows). Page 17 of 20

18 Fig. 10: Focus of active intraparenchymal hemorrhage (white arrows). Fig. 11: Focus of active intraparenchymal hemorrhage (Black arrows). Page 18 of 20

19 Conclusion The Baltimore CT Severity Index is a more comprehensive method to classify splenic trauma with its detailed inclusion of vascular injury that can identify patients at increased risk for future bleeding. Splenic artery embolization can be used to successfully treat hemodynamically stable patients with severe splenic injury despite a high CTSI score with resultant reduced hospital stay. Personal information References Marmery H, Shanmuganathan K, Alexander MT, Mirvis SE. Optimization of selection for nonoperative management of blunt splenic injury: comparison of MDCT grading systems. AJR Am J Roentgenol 2007;189: Moore EC, Cogbill T, Jurkovich G, Shackgford S, Malangoni M, Champion H. Organ injury scaling: spleen and liver (1994 revision). J Trauma 1995;38: Schurr MJ, Fabian TC, Gavant ML, et al. Management of blunt splenic trauma: computed tomographic contrast blush predicts failure of nonoperative management. J Trauma 1995; 39: Shanmugathan K, Mirvis SE, Boyd-Kranis R, Takada T, Scalea TM. Nonsurgical management of blunt splenic trauma: use of CT criteria to select patients for splenic arteriography and potential endovascular therapy. Radiology 2000; 217:75-82 Peitzman AB, Heil B, Rivera L, et al. Blunt splenic injury in adults: Multiinstitutional Study of the Eastern Association for the Surgery of Trauma. J Trauma. 2000;49: Sabe AA, Claridge JA, Rosenblum DI, et al. The effects of splenic artery embolization on nonoperative management of blunt splenic injury: a 16-year experience. J Trauma 2009; 67:565 J.A. Requarth, R.B. D'Agostino, P.R. Miller. Nonoperative management of blunt splenic injury with and without splenic artery embolotherapy: a metaanalysis. J Trauma, 71 (2011), pp Miller PR, Chang MC, Hoth JJ, et al. Prospective trial of angiography and embolization for all grade III to V blunt splenic injuries: nonoperative management success rate is significantly improved. J Am Coll Surg 2014; 218:644 Page 19 of 20

20 9. Wei B, Hemmila MR, Arbabi S, Taheri PA, Wahl WL. Angioembolization reduces operative intervention for blunt splenic injury. J Trauma 2008; 64: Olthof DC, van der Vlies CH, Scheerder MJ, de Haan RJ, Beenen LF, Goslings JC, et al. Reliability of injury grading systems for patients with blunt splenic trauma. Injury2014;45: Uyeda JW, LeBedis CA, Penn DR, Soto JA, Anderson SW. Active hemorrhage and vascular injuries in splenic trauma: utility of the arterial phase in multidetector CT. Page 20 of 20