New biomarker holds promise in treating vitreomacular traction disorders. Dermot McGrath reports from the EURETINA 2021 Virtual Congress.
The extent of preoperative traction is the most significant predictive factor for the success of ocriplasmin therapy in vitreomacular traction (VMT) disorders, according to a study presented at the 2021 congress.
“We found the optimal cut-off value of the VMT diameter for ocriplasmin therapy could be statistically defined as 480 μm and may thus be a new quantitative biomarker to predict treatment success,” Sami Al-Nawaiseh MD said.
Further factors with significant predictive influence on outcomes included age, lens status, hypertension, and absence of diabetes mellitus.
Vitreomacular traction is characterised by anomalous posterior vitreous detachment accompanied by anatomic distortion of the fovea, which may include pseudocysts, macular schisis, cystoid macular oedema, and subretinal fluid. The current classification for vitreomacular traction is set by the International Vitreomacular Traction Study Group, explained Dr Al-Nawaiseh, and can be subclassified by the diameter of vitreous attachment to the macular surface as measured by OCT.
Approved by the US FDA in 2012, ocriplasmin works by dissolving the proteins that link the vitreous to the macula, resulting in posterior detachment of the vitreous from the retina. Dr Al-Nawaiseh’s retrospective, consecutive, interventional study included 106 patients with symptomatic VMT with a deformed foveal contour. All of the patients received ocriplasmin through intravitreal injection. Exclusion criteria included diagnosis of full-thickness macular hole, presence of other vitreoretinal pathologies such as epiretinal membrane, and missing or substandard OCT images.
Among the grouped risk factors analysed, phakic patients had a higher success rate than pseudophakic patients. Hypertension and diabetes mellitus type 2 absence also had a significant influence on the resolution of the VMT. For the continuous factors, patients with younger age and a smaller adhesion diameter before injection were shown to be predictive of anatomical success, Dr Al-Nawaiseh said.
“The statistically optimal threshold value for the adhesion size was 480 μm. Eyes below this limit had a 6.84-fold better chance of VMT resolution compared to eyes with a larger adhesion diameter,” he said.
Looking at the results in more detail, Dr Al-Nawaiseh said the overall success rate in this cohort was 60.4%. Broken down by traction diameter, this equated to 0% success for VMT greater than 1,500 μm, 64% for focal VMT less than 1,500 μm, and 76.5% for VMT less than 480 μm.
Comparing the results to earlier studies in the scientific literature, most of which reported a success rate in the range of 42% to 46%, Dr Al-Nawaiseh said patient selection was key to obtaining optimal outcomes.
“I think this emphasises the importance of rigorous patient selection as many of the earlier studies included patients with epiretinal membranes and other macular comorbidities,” he said.
