Sequelae of Endoscopic Inguinal Hernia Repair : Incidence, evaluation and management

Abstract

The endoscopic preperitoneal technique (TEP) is an appealing inguinal hernia repair technique, theoretically superior to other approaches. In practice some problems remain unsolved. Real incidences of chronic postoperative inguinal pain (CPIP) and other important sequelae of endoscopic hernia repair are unknown. A clear work-up algorithm to assess the type of pain and to subsequently treat it accordingly is currently not available. The discussion about superiority of a lightweight mesh for endoscopic repair is ongoing and finally, publications about treatment recommendations for women with an inguinal hernia are scarce. CPIP is the most important sequel after inguinal hernia repair which can be caused by nerve damage (neuropathic pain) or inflammatory induced (nociceptive) pain. A new algorithm to diagnose the type of pain and then select the appropriate therapy was designed and analysed in this thesis. Patients with the diagnosis of neuropathic pain could be filtered out and treated successfully in 83%. The incidence of CPIP after TEP is lower compared to open anterior repair and the cause is thought to be inflammation related. It is unclear whether the diagnostic tools used for the assessment of CPIP are appropriate for patients after TEP. We evaluated the role of MRI in those patients and demonstrated that MRI was of little help to identify a specific cause of inguinal hernia repair-related pain. However, MRI can reassure patients by showing adequate position of the mesh with no abnormalities other than minor fibrosis. MRI is also useful to identify non-operation-related causes of groin pain. To design appropriate algorithms for the assessment and treatment of CPIP after TEP, detailed and well-designed data assessing the natural time course of groin pain are important. In this thesis we described the incidence and course of inguinal pain over time following TEP hernia repair in detail and concluded that most pain after TEP fades out after three to six months and less than 1 % of the patients reported clinical relevant pain at one year postoperatively. CPIP and discomfort can be caused by fibrosis resulting after the inflammatory reaction of the implanted mesh. We performed a large randomized clinical trial to compare CPIP and mesh feeling after TEP with a lightweight Ultrapro or a heavyweight Prolene mesh. Three months after TEP repair, there were no significant differences between the two meshes regarding the incidence of CPIP, mesh feeling or any other endpoint. At one and two years postoperatively we observed a higher incidence of clinically relevant pain and more recurrences in the lightweight mesh group compared to the heavyweight group. Finally we described the results of endoscopic inguinal hernia repair in women. To diagnose the correct hernia type preoperatively is difficult. This is confirmed by a high incidence of femoral hernias in women. As endoscopic hernia repair offers the opportunity to identify all hernia subtypes intra-operatively, this technique is recommended as the most appropriate treatment.