Novel Angiographic Classification of Polypoidal Choroidal Vasculopathy and Impact on 5-Year Visual Outcomes
Narrative Responses:
Purpose
Polypoidal choroidal vasculopathy (PCV) has high prevalence among Asians, with variable clinical course and visual prognosis, suggesting the existence of clinical subtypes. We describe a novel classification system for PCV based on indocyanine-green (ICG) angiography, and correlate it with clinical outcomes.
Methods
Interventional longitudinal 5-year study of 112 consecutive patients with PCV. Images were independently graded by two Consultant ophthalmologists. Risk factors for clinical outcomes were analysed using multivariate analysis.
Results
Three distinct PCV subtypes were seen: Type I (inter-connecting channels)–25%; Type II (branching vascular network)–26.2%; Type III (active leakage)–48.8%. The ICG subtypes correlated with specific, differentiating pathologic features which were consistently demonstrated on OCT. At all review periods, the highest rate of moderate visual loss occurred in Type III PCV, followed by Types II and I (41.2% vs. 11.1% vs. 0% at 5 years). Good visual outcomes (≥6/12) were highest in Type I, compared to Types II and III (83.3% vs. 62.5% vs. 20%, p=0.034). Independent risk factors for visual outcomes were PCV subtype (odds ratio [OR] 2.84, p=0.025) and age (OR 0.91, p=0.022).
Conclusion
We have established a novel classification system for PCV based on angiography and anatomy. The clinical and visual outcomes are reliably predicted by this classification, demonstrating that PCV consists of distinct, previously unrecognized, clinical subtypes instead of a single disease entity as originally believed. This classification system has potential application in clinical practice and multicenter randomized trials.