Intra-abdominal adhesions in ultrasound. Part I: The visceroperitoneal bordeline, anatomy and the method of examination

Andrzej Smereczyński1, Teresa Starzyńska1, Katarzyna Kołaczyk2, Stefania Bojko3, Maria Gałdyńska3, Elżbieta Bernatowicz3, Anna Walecka2

Affiliation and address for correspondence
J Ultrason 2012; 12 (51): 472–478

It needs to be emphasized that ultrasonography is a primary test performed in order to evaluate the abdominal wall and structures located in their vicinity. It allows for the determination of the anatomy and lesions in this localization. Thorough knowledge concerning the ultrasound anatomy of the tested structures constitutes a basis of all diagnostic successes. Therefore, this part of the article is devoted to this subject matter. The possibility to diagnose intra-abdominal adhesions with ultrasound is underestimated and rarely used. The aim of this paper is to discuss and document the ultrasound anatomy of the posterior surface of the abdominal wall as well as to present techniques directed at the detection of adhesions, in particular the visceroperitoneal ones. The posterior surface of the abdominal wall constitutes an extensive tissue area of complex structure, with folds and ligaments surrounded by various amounts of the epiperitoneal fat. In some places, this tissue separates the components of the fascia and peritoneum complex. The ultrasound manifestation of this complex is two hyperechogenic lines placed parallelly to each other in the places where they are not separated by the accumulated adipose tissue. Another factor which separates the peritoneum from the viscera is of dynamic character. It is a so-called visceral slide induced by easy or deep breathing. Its size should not be lower than 1 cm and the deflections gradually and symmetrically diminish from the epigastric to hypogastric region. Last but not least, the evaluation of the reciprocal relation of the abdominal wall with viscera may be aided by rhythmical manual compressions on the abdominal wall (ballottement sign) performed below the applied ultrasound transducer. During this test, the size of the visceral slide in relation to the abdominal wall is observed. The maneuver is usually performed in uncooperative patients or those with shallow breath. The authors’ own experiences indicate that the effectiveness of the test is increased when lower extremities are moderately bent. This relaxes the muscle tension in the anterior wall of the abdomen. To assess the condition of these structures, linear transducers with the frequency of 5–9 MHz prove the most appropriate. In obese patients, a convex transducer with the frequency of 3.5–5 MHz also may be used. The acoustic focus should be set on the borderline of the abdominal wall and viscera and in order to visualize the changes it might be helpful to use harmonic, compound and XRes imaging. When examining the abdominal wall, the cross and longitudinal sections should be made. The complete evaluation of the visceroperitoneal borderline includes nine segments – three in the epigastrium, three in the mid-abdomen and three in the hypogastrium.

anatomy, visceroperitoneal complex, epiperitoneal fat, visceral slide test, ultrasound