Sir,

We would like to congratulate P O'Reilly and S Beatty on reporting their initial experiences with 25-gauge transconjunctival sutureless vitrectomy. It is behoven on us as surgeons to clearly demonstrate an advance in patient's experience or improvement in postoperative outcomes before introducing surgical innovations to our routine practise. This article adds to the evidence we require to make this judgement in the case of 25-gauge vitrectomy.

Given that the authors observed postoperative hypotony in 25.6% cases (n=10) and postoperative haemorrhage in 10.3% cases (posterior segment haemorrhage and hyphaema), we cannot agree with their conclusion that ‘TSV 25M vitrectomy is a safe and effective procedure’. In addition, this paper does not present sufficient evidence to support a further claim that ‘transconjunctival sutureless vitrectomy does not compromise the surgical or visual outcome of internal posterior segment surgery’.

A retrospective study of this nature is likely to reflect a selection bias towards the inclusion of uncomplicated cases suitable for training a surgeon in a new technique. Despite this, postoperative hypotony was common necessitating daily review of the patient. Any possible gains in comfort or decreased surgical time are thus outweighed by the very real inconvenience and cost of daily review for both patients and staff.

Further clarification on the cause of postoperative haemorrhage in this study is also required. We note that the presenting complaint was vitreous haemorrhage in ten cases and it would be important to know whether postoperative haemorrhage occurred exclusively in this group.

Finally, the authors alluded to the possible risk of endophthalmitis following postoperative hypotony. Concerns about an increased rate of endophthalmitis following 25-gauge vitrectomy have already been raised in the literature.1, 2, 3 This study presents the results from 39 eyes and larger numbers would be required to determine if the risk of endophthalmitis is increased, and therefore whether this technique really is as safe as the authors' claim.

In conclusion, we would caution surgeons to examine the evidence carefully before replacing current practise with a technique that has yet to demonstrate a real improvement in long-term patient outcomes.