In general, the decision to remove the lens for a glass excision surgery is based on the degree of clouding of the lens and whether or not it interferes with the wave excision surgery. The full name of a bolectomy is a vitrectomy, and as the name implies, the vitreous body is removed. The vitreous is a jelly-like tissue when young that gradually liquefies with age, and some patients experience vitreous hemorrhage and clouding. The vitreous body serves primarily as a filler for the eye. The vitreous body needs to be removed due to a number of diseases such as retinal detachment and vitreous hemorrhage. If the patient has clear crystals, the vitrectomy does not need to remove the crystals at the same time. If the crystals are cloudy and cataracts occur, it is best to remove the crystals at the same time as the vitrectomy. Generally, vitrectomy is a more complicated surgery in ophthalmology, and it is recommended to go to a regular hospital for the surgery.