Primary angle-closure glaucoma(PACG)is highly prevalent in Chinese population,and some PACG has more serious conditions with persistent elevated intraocular pressure(IOP).The results of previous animal experiments showed that as IOP gradually increased,aqueous humor gradually diffused backwards.Previous clinical studies revealed that PACG is often accompanied by zonu-lopathy,vitreous zonule rupture and intravitreal fluid accumulation.We speculate that in some PACG,due to the closure of the anterior chamber angle,the aqueous misdirection happens.The aqueous flows backwards into the space between the lens zonular,into retrolental space,and even into the anterior vitreous body,pushing the lens-iris diaphragm forward,and further increasing the aqueous outflow re-sistance.A vicious cycle has formed,leading to refractory elevated IOP.Meanwhile,the anatomical abnormalities caused by aqueous misdirection also explain the increased risk of intraoperative complications and more challenging treatment in PACG patients with ele-vated IOP.(Ophthalmol CHN,2024,33:178-181)