啥叫occlusive, one as non-occlusive ？ 谁给翻译一下，看不懂。

The American Society of Retina Specialists (ASRS) Research and Safety in Therapeutics (ReST) Committee collaborated with Apellis Pharmaceuticals to investigate the reported retinal vasculitis events. Out of the six reported cases, two were confirmed as occlusive, one as non-occlusive and the remaining three were undetermined due to limited information. These events occurred between 7 and 13 days after the initial administration of Syfovre, with no specific lots implicated.