Use of imaging for pre- and post-operative characterisation of ventral hernia: systematic review

Objective: Complex ventral hernia (CVH) repair is performed increasingly, exacerbated by the obesity epidemic. Imaging can characterise hernia morphology and diagnose recurrence. By systematic review we investigated the extent to which studies employ imaging. Methods: The PubMed database was searched for studies of ventral hernia repair from January 1995 to March 2016. Hernias of all size were eligible. Independent reviewers screened articles and extracted data from selected studies related to study design, use of pre- and post-operative hernia imaging and the proportion of subjects imaged. The review was registered: PROSPERO CRD42016043071. Results: 15,771 records were identified initially. 174 full-texts were examined and 158 ultimately included in the systematic review [31 randomised controlled trials (RCT s); 32 cohort studies; 95 retrospective cohort studies]. 31,874 subjects were reported overall. Only 19 (12%) studies employed pre-operative imaging for hernia characterisation and 46 (29%) post-operatively [equating to 511 (2%) of all pre-operative subjects and 1123 (4%) post-operative]. Furthermore, most studies employing imaging did not do so in all subjects: Just 6 (4%) of the 158 studies used imaging in all subjects pre-operatively and just 4 (3%) post-operatively, i.e. imaging was usually applied to a proportion of patients only. Moreover, the exact proportion was frequently not specified. Studies using imaging frequently stated that "imaging", "radiography" or "radiology" was used but did not specify the modality precisely nor the proportion of subjects imaged. Conclusion: Despite the ability to characterise ventral hernia morphology and recurrence with precision, most indexed studies do not employ imaging. Where imaging is used, data are often reported incompletely. Advances in knowledge: (1) This systematic review is the first to focus on the use of imaging in surgical studies of ventral hernia repair. (2) Studies of ventral hernia repair rarely use imaging, either to characterise hernias pre-operatively or to diagnose recurrence, despite the latter being the primary outcome of most studies. (3) Failure to use imaging will result in incomplete hernia characterisation and underestimate recurrence rates in studies of surgical repair.