Segmental Arterial Mediolysis: Do you remember what to search for?

Congress:

ECR 2018

Poster Number:

C-3145

Type:

Educational Exhibit

Keywords:

Dissection, Aneurysms, Diagnostic procedure, Computer Applications-3D, MR-Angiography, CT-Angiography, CT, Contrast agents, Arteries / Aorta, Abdomen, Ischaemia / Infarction

Authors:

A. Fuentealba¹, D. Ramirez², N. Rossel¹, P. Almarza¹, A. Pizarro¹, M. CASTRO¹, D. I. Herquinigo¹; ¹Santiago/CL, ²Santiago, METROPOLITANA/CL

DOI:

10.1594/ecr2018/C-3145

DOI-Link:

https://dx.doi.org/10.1594/ecr2018/C-3145

Fig. 1: Segmental Arterial Mediolysis: Do you remember what to search for?

Fig. 2: Vacuolar degeneration and lysis of the media layer, hence the name...

Fig. 3: Celiac trunk dissection with left hepatic artery aneurysm.

Fig. 4: Endoluminal hypodense linear image in the fine celiac trunk (red arrows),...

Learning objectives

After reviewing this educational exhibit you will be able to: Understandphysiopathology of segmental arterial mediolysis (SAM) with radiologiccorrelation Learn SAM diagnostic criteria, differential diagnosis and updated clinical management

Background

Segmental arterial mediolysis (SAM) is an uncommon vasculopathy of unknown etiology, notinflammatory or atherosclerotic. SAM can presents as an aneurysm rupture with life threating abdominal, retroperitoneal or intracraneal hemorrhage, resulting in end organ ischemia. Common symptoms include abdominal pain, shock, or neurologic symptoms.It develops most commonly in middle and old age people with no genderpreponderance. Segmental arterial mediolysis commonly affects the large branches of the aorta, such as celiac trunk, superiormesenteric artery (SMA), inferior and renal arteries. Intracraneal arteries can also be involved. Also multiple...

Findings and procedure details

Slavin et al described fiveangiographic appearence of SAM, with a radiological sign associated. All the radiological signs are shown in the images in this section. Arterial dilatation: muscular lysis with fibrin deposit in the outer layer. Single aneurysm:destruction of the internal elastic lamina, progresses towards the intima in a segmental way. Multiple aneurysm:multiple segmental aneurysms with areas of normal vascular wall. Morphology in "string of beads". Dissecting hematomas:separation between the external elastic lamina and the adventitia. Arterial stenosis and occlusion:repair phenomena and fibrosis. Diagnosis SAM...

Conclusion

Take home points Even thoughhistology remains the gold standard,diagnosis can be established based on clinicalpresentationand imaging. Angiography with or without computed tomography can be diagnostic showing segmental narrowing and dilatation or aneurysm as the "string of beads" appearence. Fibromuscular dysplasiacan also present similar findings and is an important differential diagnosis,but it mainly develops in young to middle-aged women Becauseof the rarity of SAM, no standard treatment has been developed;endovascular management and open surgery have been reported, being both controversial.

Personal information

References

Horsley-Silva et al.Segmental arterial mediolysis: a case of mistaken hemorrhagic pancreatitis and review of the literature. JOP2014 Jan 10;15(1):72-7. doi: 10.6092/1590-8577/2036. Christine P. Chao. Segmental Arterial mediolysis. Seminars in interventional radiology/volume 26, number 3 2009 Richard E. Slavin. Segmental arterial mediolysis: course, sequelae, prognosis,and pathologic–radiologic correlation. Cardiovascular Pathology 18 (2009) 352–360. Kinan Alhalabi , Christine Menias, Robert Hines, Ihsan Mamoun, Sailendra Naidu. Imaging and clinical findings in segmentalarterial mediolysis (SAM). Abdom Radiol (2016)DOI: 10.1007/s00261-016-0887-4 Sanjeeva P. Kalva, Bhanusupriya Somarouthu,,Michael R. Jaff, Stephan Wicky,. Segmental Arterial...