<prompt> Mannitol decreases the intraocular pressure by ?Withdrawing water from vitreousIncreasing uveoscleral outflowIncreasing aqueous through trabecular meshworkInhibiting the enzyme carbonic anhydrase in the ciliary body  <response>: Ans. is a i.e., Withdrawing water from vitreous By osmotic action mannitol encourages movement of water from aqueous humour -- decrease. Mannitol is used in angle closure narrow angle, acute congestive glaucoma. Treatment of acute congestive glaucoma o Definitive therapy is surgery laser iridotomy Drugs are used to decrease the i.o.t. during an acute attack. o Approch is : Sta i.v. mannitol or i.v. acetazolamide When i.o.t. stas falling, sta topical pilocarpine or b -blocker timolol. Apraclonidinelatanoprost may be added. Once i.o.t. is reduced, surgery is done. 