The Amsterdam Debates
Vitrectomy methods, uveitis work-ups topics of spirited debates
The Amsterdam Retina Debate has become a veritable institution within EURETINA, appearing every year to cater to host experts willing to debate controversial or unresolved topics that have no obvious “right” or “wrong” answer.
Chaired by Professor Sarit Lesnik-Oberstein of the Netherlands, this year’s debate took place at the 19th Annual EURETINA Congress in Paris. It treated delegates to two separate battles: the first concerned the relative merits of cryotherapy versus laser in vitrectomy, while the second considered the extent to which extensive investigation is needed in uveitis cases.
Arguing against the statement, “Cryotherapy is Superior to Laser in Vitrectomy,” Paul Sullivan, Moorfields Eye Hospital, London, United Kingdom, started with a 77% majority in the pre-debate voting.
“Numerous randomised controlled trials have shown no significant difference between cryotherapy and laser, but does this mean that they are equally effective?” asked Dr Sullivan. “In order to prove the superiority of one over the other, we would need a sample size of at least 868 eyes,” making such a study unlikely.
To make his case, Dr Sullivan focused on what he considers the inferior safety profile of cryotherapy. “Whereas retinal laser affects only the retina and the underlying retinal pigment epithelium, cryotherapy, which must be applied exteriorly, damages the conjunctiva, sclera, choroid and retina.”
Dr Sullivan also highlighted the serious dangers of severe overtreatment due to the difficulty of visualising recently treated regions. “I have also seen eyes in which the optic nerve and the macula had been frozen and thus scarred, leading to profound vision loss,” although he admitted that these were rare complications and generally only occurred in the hands of very inexperienced surgeons.
“Indirectly, cryotherapy both promotes inflammation and enhances intravitreal dispersion of viable retinal pigment epithelial cells, both of which are thought to increase the risk of proliferative vitreoretinopathy (PVR),” he said.
Rumana Hussain, St Paul’s Eye Unit, Liverpool, United Kingdom, argued against the topic’s current consensus. She started by countering Dr Sullivan’s safety concerns, referring to the book he wrote on vitreoretinal surgery, in which he states that “cryotherapy is safe and effective”. She also cited the risk of lens touch and the possibility of laser over-treatment, leading to retinal necrosis and new retinal breaks.
Dr Hussain then highlighted the therapeutic advantages. “Laser can’t be used in the presence of subretinal fluid, it is difficult to use for blonde fundi and it cannot be used to treat adequately in the presence of lens or media opacities,” she said.
“Cryotherapy’s applications extend from retinal detachment repair to the treatment of more difficult entities like vasoproliferative tumours.”
Despite a lively, entertaining and well-researched defence of cryotherapy, the audience stuck with their pre-debate opinions and selected laser as the superior modality for retinal treatment.
UVEITIS: HOW MUCH INVESTIGATION NEEDED?
The second debate, “Uveitis Always Needs Extensive Investigation”, pitted Lisa Faia MD, Associated Retinal Consultants, Michigan, USA, against Emmanuel Ramos de Carvalho, Moorfields Eye Hospital, London, United Kingdom.
Prior to the debate, delegates voted against the notion that uveitis always needs to be extensively investigated. Dr Faia argued convincingly against the “shotgun approach”.
“There is no single, pre-determined work-up for the uveitis patient. Instead, testing for each individual should be focused and efficient, and based on the ocular examination, patient history and associated signs and symptoms.”
She cited stress to the doctor, patient and healthcare system that could be incurred by unnecessary testing.
“False positives cause patient anxiety, such as in a case in which a patient who was referred to me had become convinced that he had lupus simply because an unnecessary test of his ANA was borderline positive,” said Dr Faia.
In addition, unnecessary testing can be expensive, and we are morally obligated to follow up on false positives with additional testing.
Dr Faia emphasised that extensive testing is warranted when the diagnosis remains unknown, when the disease does not respond to treatment as predicted, or when new symptoms arise.
Dr Ramos de Carvalho maintained that the relative rarity of uveitis warranted a maximal approach to get to a correct diagnosis.
“Otherwise, we risk missing severe diseases in individual patients. We are only able to make a specific diagnosis in 61% of anterior uveitis cases and 15% of intermediate uveitis cases.”
In posterior uveitis, even though tough a specific diagnosis can be made in 78%, the other 22% could represent very dangerous associated pathology, so further investigations are crucial.
“There is a wrong assumption amongst ophthalmologists that uveitis typically is a manifestation of ‘something else’ and the ‘something else’ must be identified, regardless of cost,” said Dr Ramos de Carvalho. He believes that doctors should investigate solely whenever it is felt that uveitis could be a manifestation of a serious systemic disease.
“Starting with a thorough examination, we can proceed to an intelligent differential diagnosis and selected investigations to arrive at the correct diagnosis and deliver the appropriate treatment.”
In the end, the audience agreed with Dr Faia.
Paul Sullivan: Paul.Sullivan@moorfields.nhs.uk
Rumana Hussain: Rumana.email@example.com
Lisa Faia: firstname.lastname@example.org
Emmanuel Ramos de Carvalho: email@example.com