I would like to congratulate Dr. Zendejas and colleagues for reporting their recent series on the role of prophylaxis during unilateral TEP repair, intended to prevent further development of contralateral metachronous inguinal hernia [1]. Out of a large cohort of 638 patients with a pre-operative diagnosis of unilateral hernia, an incidental hernia was discovered on the contralateral side on 206 occasions (32%) and therefore repaired with mesh at the same time. The remaining patients, who had only unilateral inguinal repair during their bilateral groin exploration and no history of previous contralateral hernia repair, comprised this study cohort. With a median follow-up of almost 6 years, the risk of developing a metachronous hernia at 1, 5 and 10 years on the previously “healthy” side was 1.6, 5.9 and 11.8% respectively, or a yearly risk of just above 1%. Interestingly, in this sub-group of patients, the repair was open in 56.7%, laparoscopic trans-abdominal preperitoneal (TAPP) in 33.3% and repeat TEP in only 10%. As the authors state, the TEP approach can be quite challenging in a previously dissected Weld and therefore unlikely to be proposed as the Wrst choice of treatment. In other words, after systematic exploration of both groins for unilateral hernia repair, only a small number of those who will eventually develop a metachronous inguinal hernia will be oVered this technique again. This is regrettable knowing that TEP carries a much lower risk of chronic groin pain than open repair [2], and reduced morbidity when compared to TAPP [3]. Unfortunately, there is not much discussion about this aspect of the problem in Dr. Zendejas’s paper and I would like, therefore, to share some useful ideas. In my practice, I have set up a new policy consisting of performing pre-operative ultrasonography of the groin considered “normal” where no evidence of inguinal hernia could be clinically demonstrated [4]. As such, the chance of Wnding an associated contralateral hernia, weakness of the groin or the presence of a cord lipoma is around 30% (personal unpublished data). For those with positive ultrasonographic Wndings, a bilateral TEP mesh repair will be oVered and the remaining 70% will receive only unilateral exploration of the aVected groin, leaving the other side untouched. Should any of these patients subsequently develop a metachronous inguinal hernia, I would then recommend a repeat TEP approach as the Wrst treatment of choice. Over the last 18 months, I have completed ten repeat TEP repair of a metachronous inguinal hernia without any need for conversion or added morbidity. Although this is quite a small number, a 100% success rate suggests that, in experienced hands, a repeat TEP approach is certainly feasible in previously “virgin” pre-peritoneal space. In conclusion, I believe that if a laparoscopic surgeon chooses to systematically explore both groins in any patient with a pre-operative diagnosis of unilateral hernia, he should always place a prosthetic mesh on the contralateral side irrespective of the surgical Wndings. If, on the contrary, he prefers the safe and quite reliable option of a pre-operative ultrasonography of the “normal” groin, should this investigation be unremarkable only a unilateral dissection of the pre-peritoneal space should be performed and the pathological side repaired, leaving the other groin untouched as this does not compromise the chance of success of a repeat TEP approach. C. R. Berney (&) Bankstown-Lidcombe Hospital, Bankstown NSW 2200, Australia e-mail: berneycr@hotmail.com