Radiological evaluation of superior mesenteric artery syndrome: are aortomesenteric angle and distance measurements reliable?

Year 2025, Volume: 19 Issue: 1, 24 - 29, 30.04.2025

Eren Çamur , Berkay Ersöz , Bilal Egemen Çifçi , Mustafa Dağlı

Abstract

Objectives: To evaluate the interobserver and intraobserver consistency of aortomesenteric angle (AMA) and aortomesenteric distance (AMD) measurements in diagnosing superior mesenteric artery syndrome (SMAS), and to assess their reliability as diagnostic parameters.
Methods: This retrospective study analyzed 200 abdominal CT scans of patients (124 females, 76 males; aged 17–42) with a preliminary diagnosis of SMAS between May 2021 and March 2024. AMA and AMD were measured on sagittal and oblique-sagittal images by three radiologists at two different times, independently and blinded to clinical data. Intraobserver and interobserver variability was evaluated using nonparametric statistical tests, with p<0.05 considered significant. Diagnostic thresholds were set at 22° for AMA and 8 mm for AMD.
Results: AMA measurements showed significant interobserver and intraobserver variability (p<0.05), while AMD measurements were reproducible and consistent (p>0.05). Variability in AMA led to diagnostic discrepancies in 9.1–10.4% of cases, compared to only 0.5–1.2% for AMD. These results indicate that AMA is less reliable and prone to user-dependent errors, whereas AMD offers greater diagnostic accuracy.
Conclusion: AMA measurements are influenced by factors such as patient positioning and respiratory phase, contributing to their inconsistency. AMD, in contrast, demonstrates low variability and high reliability, making it a more robust parameter in SMAS diagnosis. The study emphasizes the need to prioritize AMD over AMA in the diagnostic workflow for SMAS. AMD is a consistent and reliable parameter for SMAS diagnosis, while AMA demonstrates significant variability and potential for misdiagnosis.

Keywords

Aortomesenteric angle, aortomesenteric distance, computed tomography, reliability, superior mesenteric artery, syndrome

References

• Mathenge N, Osiro S, Rodriguez II, Salib C, Tubbs RS, Loukas M. Superior mesenteric artery syndrome and its associated gastrointestinal implications. Clin Anat 2014;27:1244–52.
• Kingham TP, Shen R, Ren C. Laparoscopic treatment of superior mesenteric artery syndrome. JSLS 2004;8:376–9.
• Mandarry MT, Zhao L, Zhang C, Wei ZQ. A comprehensive review of superior mesenteric artery syndrome. European Surgery 2010;42:229–36.
• Caterine S, Patil NS, Takrouri H, Issenman RM, Stein NR, Donnellan J, Yikilmaz A. Understanding the diagnosis of superior mesenteric artery syndrome: analysis of the location of duodenal impression on upper gastrointestinal studies. Pediatr Radiol 2023;53:2633–41.
• Lamba R, Tanner DT, Sekhon S, McGahan JP, Corwin MT, Lall CG. Multidetector CT of vascular compression syndromes in the abdomen and pelvis. Radiographics 2014;34:93–115.
• Unal B, Aktaş A, Kemal G, Bilgili Y, Güliter S, Daphan C, Aydinuraz K. Superior mesenteric artery syndrome: CT and ultrasonography findings. Diagn Interv Radiol 2005;11:90–5.
• Farina R, Foti PV, Cocuzza G, Costanzo V, Costanzo G, Conti A, Torcitto A, Pennisi M. Wilkie’s syndrome. J Ultrasound 2017;20:339–42.
• Yale SH, Tekiner H, Yale ES. Historical terminology and superior mesenteric artery syndrome. Int J Surg Case Rep 2020;67:282–3.
• Forte A, Santarpia L, Venetucci P, Barbato A. Aorto-mesenteric compass syndrome (Wilkie’s syndrome) in the differential diagnosis of chronic abdominal pain. BMJ Case Rep 2023;16:e254157.
• Applegate GR, Cohen AJ. Dynamic CT in superior mesenteric artery syndrome. J Comput Assist Tomogr 1988;12:976–80.
• Santer R, Young C, Rossi T, Riddlesberger MM. Computed tomography in superior mesenteric artery syndrome. Pediatr Radiol 1991;21:154–5.
• Agrawal GA, Johnson PT, Fishman EK. Multidetector row CT of superior mesenteric artery syndrome. J Clin Gastroenterol 2007;41:62–5.
• Ozkurt H, Cenker MM, Bas N, Erturk SM, Basak M. Measurement of the distance and angle between the aorta and superior mesenteric artery: normal values in different BMI categories. Surg Radiol Anat 2007;29:595–9.
• Makary MS, Rajan A, Aquino AM, Chamarthi SK. Clinical and radiologic considerations for idiopathic superior mesenteric artery syndrome. Cureus 2017;9:e1822.
• Arthurs OJ, Mehta U, Set PAK. Nutcracker and SMA syndromes: what is the normal SMA angle in children? Eur J Radiol 2012;81:e854–61.
• Horton KM, Fishman EK. Volume-rendered 3D CT of the mesenteric vasculature: normal anatomy, anatomic variants, and pathologic conditions. Radiographics 2002;22:161–72.
• Konen E, Amitai M, Apter S, Garniek A, Gayer G, Nass S, Itzchak Y, Konen E, Amitai M, Apter S, Garniek A, Gayer G, Nass S, Itzchak Y. CT angiography of superior mesenteric artery syndrome. AJR Am J Roentgenol 1998;171:1279–81.
• Kane KE, Koons AL. The aortomesenteric angle as an aid in diagnosing superior mesenteric artery syndrome. Clin Pract Cases Emerg Med 2017;1:140.