Retinal tears are closed by laser treatment or cryotherapy, and detached retinas are reattached surgically.Even after treatment, it can take months for the body to clear all of the blood from the vitreous. In cases of vitreous hemorrhage due to detached retina, long-standing vitreous hemorrhage with a duration of more than 2–3 months, or cases associated with rubeosis iridis or glaucoma, a vitrectomy may be necessary to remove the standing blood in the vitreous. References


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In the early 1990s Dutch scientists Arnold Reuser and Ans van der Ploeg were able to show that using alpha-glucosidase containing phosphorylated mannose residues purified from bovine testes increased the enzymes activity in normal mouse muscles.Later in 1998, Dr. Yuan-Tsong Chen and colleagues at Duke University, using the enzyme produced in Chinese Hamster Ovary cells  demonstrated for the first time that the enzyme can clear the glycogen and improved the muscle function in Pompe disease quail. The results of the work at Duke were impressive with one treated bird recovering to the point of being able to fly again.This was followed by production of clinical grade alpha-glucosidase in Chinese hamster ovary (CHO) cells and in the milk of transgenic rabbits. This work eventually culminated in the start of clinical trials with the first clinical trial including 4 babies receiving enzyme from rabbit milk at Erasmus MC Sophia Childrens Hospital and 3 babies receiving enzyme grown in CHO cells at Duke University in 1999. The currently approved Myozyme is manufactured by Genzyme Corp. in Cambridge, Massachusetts. Its development was a complex process. Genzyme first partnered with Pharming Group NV who had managed to produce acid alpha-glucosidase from the milk of transgenic rabbits. They also partnered with a second group based at Duke University using Chinese hamster ovary cells. In 2001, Genzyme acquired Novazyme which was also working on this enzyme. Genzyme also had its own product (Myozyme) grown in CHO cells under development.