Incarcerated Spigelian Hernia
LLQ Abdominal pain • Xray of the Week 2018
An 83 yo F presented to the Emergency Department with suspected diverticulitis. What is the diagnosis?
Figure 1. Axial (A) and coronal (B) non-contrast CT of the abdomen and pelvis.
Figure 2. Axial (A) and sagittal (B) non-contrast CT of the abdomen and pelvis. Red arrow: Spigelian hernia with surrounding mesenteric fat stranding indicative of incarceration and small amount of fluid. Green arrow: lateral border of the rectus abdominis muscle.
Figure 3. Axial non-contrast CT of the pelvis. Right sided Spigelian hernia containing only mesenteric fat.
Discussion:
Spigelian hernia is a rare abdominal hernia, which accounts for about 1% of ventral hernias. The peak incidence is in the 4th to 7th decades. The orifice of a Spigelian hernia is located in the Spigelian fascia, between the lateral border of the rectus abdominis muscle and the semilunar line, through the transversus abdominis aponeurosis. As seen in this case, there is a high risk of bowel incarceration and strangulation. (Fig. 1-2)
The most common symptom is pain which varies depending on the location and contents of the hernia. Since the hernia lies deep to a muscle and there frequently is no abdominal wall bulge, it is difficult to diagnose clinically.
CT is usually diagnostic, demonstrating a hernia sac protruding through the linea semilunaris containing bowel or fat.(Fig. 1-3) Sonography may suggest the diagnosis with a complex mass in the anterolateral aspect of the abdominal wall, which may contain fluid or gas-filled loops of bowel. Treatment is surgical and there is a low risk of recurrence.
References:
1. Spangen L. Spigelian hernia. World J Surg. 1989;13 (5): 573-80.
2. Harrison LA, Keesling CA, Martin NL et-al. Abdominal wall hernias: review of herniography and correlation with cross-sectional imaging. Radiographics. 1995;15 (2): 315-32.
3. Mittal T, Kumar V, Khullar R et-al. Diagnosis and management of Spigelian hernia: A review of literature and our experience. J Minim Access Surg. 2008;4 (4): 95-98.
4. Rettenbacher T, Hollerweger A, Macheiner P, et al. Abdominal Wall Hernias: Cross-Sectional Imaging Signs of Incarceration Determined with Sonography AJR Am J Roentgenol. 2001;177 (5): 1061-1066
5. Kirby, R. Strangulated Spigelian hernia. Postgraduate Medical Journal (1987) 63, 51-52
6. Stabile Ianora AA, Midiri M, Vinci R, et al. Abdominal wall hernias: imaging with spiral CT. European Radiology. June 2000, Volume 10, Issue 6, pp 914–919
7. Aguirre DA, Casola G, Sirlin C. Abdominal wall hernias: MDCT findings. AJR Am J Roentgenol. 2004;183 (3): 681-90.
Kevin M. Rice, MD is president of Global Radiology CME and serves as the Chief of staff and Chair of the Radiology Department of Valley Presbyterian Hospital in Los Angeles, California and is a radiologist with Renaissance Imaging Medical Associates. Dr. Rice's passion for state of the art radiology and teaching includes acting as a guest lecturer at UCLA. Dr. Rice co-founded Global Radiology CME with Natalie Rice to provide innovative radiology education at exciting international destinations, with the world's foremost authorities in their field. In 2016, Dr. Rice was nominated and became a semifinalist for a "Minnie" award for the Most Effective Radiology Educator.
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