Retinal Detachment

Retinal detachment is a disorder of the eye in which the retina peels away from its underlying layer of support tissue. Initial detachment may be localized, but without rapid treatment the entire retina may detach, leading to vision loss and blindness. It is a medical emergency.

The retina is a thin layer of light-sensitive tissue on the back wall of the eye. The optical system of the eye focuses light on the retina much like light is focused on the film in a camera. The retina translates that focused image into neural impulses and sends them to the brain via the optic nerve. Occasionally, posterior vitreous detachment, injury or trauma to the eye or head may cause a small tear in the retina. The tear allows vitreous fluid to seep through it under the retina, and peel it away like a bubble in wallpaper.

A rhegmatogenous retinal detachment occurs due to a hole, tear, or break in the retina that allows fluid to pass from the vitreous space into the subretinal space between the sensory retina and the retinal pigment epithelium.

Treatment

There are several methods of treating a detached retina which all depend on finding and closing the holes (tears) which have formed in the retina.

Cryotherapy (freezing) and laser photocoagulation are treatments used to create a scar/adhesion around the retinal hole to prevent fluid from entering the hole and accumulating behind the retina and exacerbating the retinal detachment. Cryopexy and photocoagulation are generally interchangeable. However, cryopexy is generally used in instances where there is a lot of fluid behind the hole; laser retinopexy will not take.

Scleral Buckle surgery

Scleral buckle surgery is an established treatment in which the eye surgeon sews one or more silicone bands (bands, tyres) to the outside of the eyeball. The bands push the wall of the eye inward against the retinal hole, closing the hole and allowing the retina to re-attach. The bands do not usually have to be removed. The most common side effect of a scleral operation is myopic shift. That is, the operated eye will be more short sighted after the operation. Radial scleral buckle indicated to U-shaped tears or Fishmouth tears and posterior breaks. Circumferential scleral buckle indicated to multiple breaks, anterior breaks and wide breaks. Encircling buckles indicated to breaks more than 2 quadrant of retinal area, lattice degeration located on more than 2 quadrant of retinal area, undetecable breaks, proliferative vitreous retinopathy and inexperienced surgeon.

Pneumatic Retinopexy

This operation is generally performed in the doctor’s office under local anesthesia. It is another method of repairing a retinal detachment in which a gas bubble (SF6 or C3F8 gas) is injected into the eye after which laser or freezing treatment is applied to the retinal hole. The patient’s head is then positioned so that the bubble rests against the retinal hole. Patients may have to keep their heads tilted for several days to keep the gas bubble in contact with the retinal hole. The surface tension of the air/water interface seals the hole in the retina, and allows the retinal pigment epithelium to pump the subretinal space dry and pull the retina back into place. This strict positioning requirement makes the treatment of the retinal holes and detachments that occurs in the lower part of the eyeball impractical. This procedure is usually combined with cryopexy or laser photocoagulation.

Vitrectomy

Vitrectomy is an increasingly used treatment for retinal detachment in countries with modern healthcare systems. It involves the removal of the vitreous gel and is usually combined with filling the eye with a gas bubble (SF6 or C3F8 gas). An advantage of this operation is that there is no myopic shift after the operation. A disadvantage is that a vitrectomy always leads to more rapid progression of a cataract in the operated eye. In many places vitrectomy is the most commonly performed operation for the treatment of retinal detachment.

Ignipuncture

Ignipuncture is an outdated procedure that involves cauterization of the retina with a very hot pointed instrument. It was pioneered and named by Jules Gonin in the early 1900s.

After treatment, patients gradually regain their vision over a period of a few weeks, although the visual acuity may not be as good as it was prior to the detachment, particularly if the macula was involved in the area of the detachment. However, if left untreated, total blindness could occur in a matter of days.