Usefulness of the Twinkling Artifact in Identifying Implanted Mesh After Inguinal Hernia Repair

Objectives-Implanted mesh for inguinal hernia repair is often difficult to visualize with gray scale sonography and may present without the knowledge of the sonographer. We sought to evaluate the utility of the twinkling artifact produced by inguinal mesh to assist in mesh identification. Methods-Two reviewers evaluated focused sonographic examinations of 44 inguinal regions, 24 of which had implanted inguinal mesh. The sonographic examinations consisted of static gray scale and color Doppler images with both linear and curvilinear array transducers. The presence of the twinkling artifact and visibility of the mesh were graded on a 4-point visibility scale. Results-Inguinal mesh was not easily identified on gray scale imaging using either the curvilinear array (P=.5) or linear array (P=.5) transducer. The mesh was definitely seen in 3 of 24 inguinal regions using the linear array transducer and 2 of 24 inguinal regions using the curvilinear array transducer. In 79% of inguinal regions with mesh, the twinkling artifact was produced with the curvilinear array transducer only. The artifact was not elicited when using the linear array transducer. With the use of the curvilinear array transducer and the presence of the twinkling artifact, there was a significant chance of correctly identifying the presence of mesh (P<.005) in the entire study group. Conclusions-Standard gray scale imaging alone is not reliable when identifying inguinal mesh. The twinkling artifact was present in 79% of inguinal regions with mesh when evaluated with a low-frequency curvilinear array transducer.