The idea of removing Hunner lesions to improve symptoms is not new. Guy Hunner himself found that resection of lesions was one means to obtain symptom remission, although mostly short-lived so he gave up this kind of treatment. TUR was on trial more recently [1, 2] but this kind of surgery was not accepted when we started our first series. Initially, when applying TUR our goals were twofold: to obtain sufficient tissue to permit a reliable and sufficiently detailed histopathological diagnosis, and also to establish whether careful resection of lesions actually could help patients. At this stage there was some skepticism, with questions like: if you have an ulcer and by an operation create an even bigger ulcer, how is it possible that such a measure would make any improvement? There are reasonable explanations, though [3, 4]: peripheral denervation with removal of inflamed nerve endings, reduction of aggregates of potent inflammatory mediators and elimination of epithelial mast cell recruiting factors as well as epithelial and subepithelial mast cells might cause disease remission. In this context it is worth noting that perineural localization of inflammatory cells is a very typical feature in classic interstitial cystitis [5]. At the initial stage there was also much uncertainty about what Hunner lesions really look like [6] and certainly about their prevalence. Prevalence was thought to be in the range of 5–10% of subjects with bladder pain while in our series it is around 50% [7, 8]. Recent reports indicate that the use of cystoscopy and bladder distension as a routine in BPS/IC—or lack of such routine—is decisive for the number of patients with Hunner lesion you detect or miss. In centers where the traditional way of diagnostics was not abandoned prevalence similar to ours has been reported. Fortunately, the role of cystoscopy is now increasingly appreciated worldwide [9, 10].

The electrical settings were on the lowest intensity possible, still effective for resection, and there was only pin-point coagulation of bleeding vessels with no coagulation over large surfaces, with the intention to minimize development of scar tissue that could promote bladder contracture [3]. That makes the operation technically challenging and now and then also time-consuming since, based on experience, it is important to identify all lesions and remove all involved areas including the peripheral edema zone; completeness is crucial for the result. That is a limitation of this technique since it takes a very experienced surgeon to perform mostly multiple, wide resections over the entire bladder area, typically including the dome, on thin-walled bladders. Simple coagulation of lesions is much easier but carries its own downside, since radical wide coagulation in an organ prone to contraction seems risky. It is reasonable to believe that the result of TUR would be better and more durable, with less risk of inducing bladder contracture, although admittedly a reasoning of probability since at this stage there are no comparative studies. It is also worth noting that in a recent large series coagulation did not result in bladder volume decrease [11]. When comparing various reports duration of symptom relief seems to be longer following TUR.

The hitherto largest series [4] confirm the remarkable efficacy of this treatment, 92 of 103 patients having remission of symptoms after TUR, and long-term relief. Ablative treatment has stood the test of time and is today standard treatment with no need of justification as first line treatment of classic interstitial cystitis (ESSIC type 3C) [12].