Pars Plana Vitrectomy

Inside the eye, the void between the lens and the retina is filled with vitreous humor, which is a clear, viscous substance. Besides holding the retina in place, vitreous humor gives shape to the eye. However, there are various eye problems like macular hole, eye floaters, proliferative diabetic retinopathy, traumatic eye injuries, retinal detachment, macular pucker and vitreous hemorrhage, that necessitate partial or complete removal of vitreous humor. Such surgical removal of vitreous humor is called vitrectomy.

Once the vitreous humor is removed, the space is filled with gases or liquid silicone, so as to hold the retina in place. Vitrectomy procedures are classified into two main types - anterior vitrectomy and pars plana vitrectomy. The basic difference between them is that the former procedure involves partial or complete removal of vitreous humor from the anterior parts of the eye, whereas the latter involves deeper areas of the eye.

What is Pars Plana Vitrectomy

In this surgical procedure, the tubular surgical instruments are inserted into the eyes through the pars plana, which is the ciliary body that is located near the meeting point of iris and sclera. Pars plana is around four millimeters in length. It is believed to be a safe place for making incisions, as pars plana has no specific function in post-fetal eyes. So, vitrectomy procedures that make incisions through pars plana came to be known as pars plana vitrectomy. Like mentioned above, this surgery is usually done to remove vitreous humor from deeper areas.

Vitrectomy is mostly done as an outpatient procedure and sometimes an overnight hospital stay may be required. The surgery is done under general anesthesia and the affected eye will be held open with the help of a special speculum. Three incisions are made through the pars plana for insertion of instruments. One of the incisions are used to insert a tube that supply fluid that replaces the removed vitreous humor. This maintains the eye pressure and keeps it inflated during the vitrectomy procedure. Another tubular device is used to cut the vitreous humor into fine bits and suck it out. The third incision is used to insert a high intensity fiber optic light source that will light up the interior of the eye, so that the surgeon will get a clear view. The surgeon uses a special operating microscope with contact lenses, and this device allows him/her to get a clear view of the inner eye parts at different magnifications.

Usually, a pars plana vitrectomy take around one to two hours. In some complex cases involving additional surgical steps, more time will be required. In normal cases, recovery time is said to be around four to six weeks and the person has to strictly follow the doctor's instructions regarding aftercare, which may vary from one person to another. It has been observed that complications include eye infection, retinal detachment, glaucoma, cataract and bleeding. Even vision loss may happen in some cases.

In short, pars plana vitrectomy is a surgical procedure that involves removal of vitreous humor. It is recommended for those with eye problems like macular hole, retinal detachment, diabetic retinopathy and traumatic eye injuries. It is always advisable to have a clear idea about the possible risks and complications, before resorting to this method of treatment.