Purpose: We report our experience with the use of US and CT in postoperative complications of inguinal hernioplasty using a prosthetic polypropylene mesh.
Materials and methods: This study was divided into two parts. In the first we evaluated the in-vitro sonographic and CT appearance of a fragment of prosthetic mesh. In the second, we retrospectively reviewed the imaging findings in 31 patients (aged 42 to 75 years) examined after inguinal hernia repair between December 2000 and December 2002. Seventeen hernias had been repaired with a laparoscopic approach, and the others with the anterior tension-free technique proposed by Lichtenstein (12 cases) and Trabucco (2 cases). Sonography was performed to assess suspected complications between the second and the fourth postoperative day. Both high-resolution 7.5-10 MHz linear transducers and a 3.5 MHz convex probe were employed to ensure complete evaluation of superficial and deep structures. Eight obese patients also underwent CT for confirmation of the US results.
Results: At sonography the prosthetic mesh appeared as a linear hyperechoic image measuring about 2 mm in thickness, with posterior acoustic shadow and a finely irregular surface. Only one of the 17 patients examined after laparoscopic inguinal hernioplasty had a seroma; in the other 14 repaired with the anterior tension-free technique we identified 2 abscesses, 3 seromas, 2 "foldings" of the prosthetic mesh, and 2 mesh displacements with associated recurrence of hernia. CT confirmed the US results as to the presence of fluid collections, and visualised the prosthetic mesh in only 2/8 cases.
Conclusions: Sonography is a useful means of assessing postoperative changes in laparoscopic and in anterior tension-free hernia repair. It can differentiate these complications from recurrences of hernia. Colour-Doppler US can also correctly detect normal blood flow of the testes. Sonography is the only technique that can easily demonstrate the prosthetic mesh in the abdominal wall.