There are two times when a patient needs vitrectomy eye surgery for diabetic retinopathy. Patients with either a vitreous hemorrhage and/or a diabetic retinal detachment will require a vitrectomy.
Both occur when the diabetic retinopathy has advanced to “proliferative diabetic retinopathy.” By definition, abnormal blood vessels, called neovascularization have developed somewhere on the retina.
Neither case requires emergency surgery.
Neovascularization, the abnormal blood vessels, is very fragile. These delicate blood vessels have grown somewhere inside the eye; usually on the surface of the retina.
There are 3 types of neovascular tissue named based on the location; neovascularization elsewhere (NVE), neovascularization of the disc (NVD) or neovascularization on the iris (NVI).
Regardless, just remember proliferative diabetic retinopathy, by definition, means abnormal blood vessels are somewhere in the eye!
At times, these delicate blood vessels may bleed and cause a vitreous hemorrhage. Blood accumulates inside the eye and blocks the vision. Patients can’t see “out” and doctors can’t see “in.”
Though the vision loss can be dramatic, and as long as nothing else could have caused the bleeding (i.e. a retinal tear can also cause a vitreous hemorrhage), we usually wait for the blood to clear. This may take several weeks or longer.
If the blood doesn’t clear, a vitrectomy is needed to remove the blood not absorbed by mother nature.
Untreated neovascular tissue may “proliferate” or grow inside the eye. The tissue may creep along the surface of the retina much the same way ivy grows along the ground…moving slowly from one point to another.
With time, the NV may contract and start to detach the retina. This type of “traction” retinal detachment is different than retinal detachments sustained by non-diabetic patients.
A retinal detachment caused by diabetes requires vitrectomy surgery to physically cut away or remove the offending tissue pulling up on the retina.
What Does This Mean?
In both cases, laser treatment (panretinal photocoagulation or PRP) is needed to stop the neovascularization.
In the case of a vitreous hemorrhage, if the blood is not absorbed, laser can be performed at the same time as the operation. If the blood does absorb, laser treatment can be performed in the office.
For patients with a diabetic retinal detachment; however, an operation is often the best and only choice.
With routine eye examination, the neovascular tissue is often detected before bleeding or retinal detachment has occurred. Treatment can be initiated, operations avoided, and vision preserved!