A diverse range of topics from the role of blood flow in diabetic retinopathy to a new pipeline treatment for central retinal artery occlusion and an update on the risk of vasculitis after brolucizumab injections were some of the key themes covered in the EURETINA research session.
Chaired by Prof Reinier Schlingemann and Prof Martin Zinkernagel, the session opened with Tim Curtis PhD exploring how blood flow to the retina constitutes a potentially underestimated factor in the development of diabetic retinopathy. Prof Curtis has developed a non-diabetic animal model to test the hypothesis that defective autoregulation triggers the development of the vision threatening complications of diabetes by causing damage and retinal ischemia. “These animals are non-diabetic yet they exhibit defective retinal blood flow autoregulation and go on to develop a range of progressive retinal abnormalities that closely resemble what we see in diabetic retinopathy. We think that this work is really helping to further support this hypothesis that autoregulatory deficits are likely to be involved in the pathogenesis of diabetic retinopathy,” he said.
Anne Hege Aamodt MD discussed a new study of the drug tenecteplase in central retinal artery occlusion (CRAO). The study rationale stems from the updated understanding of ischemic stroke as an “episode of neurological dysfunction caused by focal, cerebral, spinal or retinal infarction,” she explained. The broad aim of the project is to assess the effect of systemic tissue plasminogen activator tenecteplase versus placebo administered within 4.5 hours of CRAO onset in patients admitted to the participating hospitals in Europe. The main endpoint is the proportion of patients with better than 0.7 logMAR visual acuity 30 (±5) days after treatment, representing an improvement in visual acuity of at least 0.3 logMAR, equal to at least 15 letters/three lines on a visual acuity chart. In addition, the study will access differences in visual field parameters and patient reported outcome measures between the groups. She noted that the study is based on a broad collaboration and interaction between leading ophthalmologists and neurologists in European centres.
Jordi Monés MD, PhD discussed the latest data to emerge from an independent safety review committee review of investigator-reported cases of intraocular inflammation (IOI), endophthalmitis, and retinal arterial occlusion in the phase 3 HAWK and HARRIER trials of brolucizumab versus aflibercept in neovascular age-related macular degeneration (nAMD). In the review, 50 brolucizumab-treated eyes were considered to have definite/probable drug-related events within the spectrum of IOI, retinal vasculitis, and/or vascular occlusion. On the basis of these cases, the incidence of definite/probable IOI was 4.6%. There were 8 cases (incidence 0.74%) of at least moderate visual acuity loss (≥15 ETDRS letters) in eyes with IOI (7 in eyes with IOI + vasculitis + occlusion). Of the 8 cases, 5 experienced their first IOI-related event within 3 months of the first brolucizumab injection (increasing to 7/8 within 6 months). The incidence of IOI in aflibercept-treated eyes was 1.1%, with at least moderate visual acuity loss in 0.14%. Dr Mones said that large patient series in real world scenarios have also shown similar numbers and emphasised that even previous brolucizumab injections without inflammation are no guarantee that subsequent injections will be safe.
The intriguing question of whether nystagmus is a retinal disease was then discussed by Maarten Kamermans PhD, who outlined his hypothesis that congenital nystagmus, involuntary oscillating small eye movements, actually results from primary deficits in the retina. “There is a causal relation between retinal ganglion cell oscillations and eye-movement oscillations. Furthermore, AII amacrine cells (ACs) are the retinal oscillators driving nystagmus and it is highly likely that other forms of infantile nystagmus have the same retinal cause,” he said.
In the final talk of the session, H. Nida Sen MD looked at the diagnostic challenges involved in primary vitreoretinal lymphoma (PVRL). She noted that the diagnosis of PVRL is frequently delayed, it is often misdiagnosed as uveitis and is the ocular cancer with the highest mortality rate in ophthalmology. She showed how a variety of cellular, molecular and systems-based approaches can be used to improve diagnosis.
All registered attendees will be able to view this session via playback on the virtual platform.
