Glaucoma treatment devices are disclosed. In various example, the glaucoma treatment devices include multiple microporous layers arranged together to form a microporous body configured to help facilitate evacuation of fluid from a fluid-filled body cavity, and reabsorption of the evacuated aqueous humor by the body through tissue surrounding the glaucoma treatment device. In some examples, the glaucoma treatment device includes one or more portions configured to resist cellular ingrowth, and one or more portions configured to permit cellular ingrowth.