There are several categories of retinal detachment: RHEGMATOGENOUS, TRACTIONAL, and SEROUS.
Rhegmatogenous retinal detachments
Rhegmatogenous retinal detachments happen because of a hole or tear in the retina, usually in the peripheral retina. Holes or tears, in turn, can happen because of pulling by the liquifying vitreous gel (a normal aging change) or can be traumatic. Once a tear is formed, fluid can get underneath the retina, and cause it to detach. The portion of the retina that is detached does not have normal vision and is often described by patients as “a veil coming over the vision”.
There are several ways in which retinal detachments can be repaired, depending of many factors such as the age of the patient, the location, distribution and number of retinal breaks, among others.
Some retinal detachments necessitate the combination of a scleral buckle and vitrectomy. Your retina specialist will examine you and tailor an individualized surgical plan.
An important factor in the visual prognosis of patients with a rhegmatogenous retinal detachment is involvement of the macula, the central bull’s-eye of the retina. Patients in whom the macula is not involved with the detachment at the time of diagnosis, usually have preserved central vision and have a better prognosis for excellent vision post operatively. Once the macula is detached and central vision affected, the prognosis for recovery of central vision is more guarded, though patients often regain excellent visual acuity.
Tractional detachments are commonly seen in diabetes but can occur in other retinal diseases that are characterized by loss of the normal blood supply to the retina over time.
In diabetes, the high sugar content of the blood causes structural changes to occur in the retina. Over time, the peripheral retina (which is responsible for one’s peripheral vision) becomes ischemic, or without normal blood supply. In response, various biochemical cascades are activated, causing the formation of new blood vessels. These blood vessels grow in a disorderly fashion, often into the vitreous cavity and can frequently bleed. If the disease continues to progress without treatment, these new, abnormal vessels regress, leaving behind scar tissue which can pull on the retina and elevate it, causing a tractional retinal detachment.
Tractional retinal detachments are repaired by releasing the scar tissue and traction on the retina, allowing the retina to settle back into its anatomic position. Because there must be advanced retinopathy to develop a tractional retinal detachment, even when such detachments are repaired successfully, vision may be limited because of long standing impaired circulation in the retina.
Serous retinal detachments
Serous retinal detachments are the accumulation of fluid under the retina, without a full thickness break in the retinal tissue itself.
Serous retinal detachments can be associated with diseases such as Central Serous Chorioretinopathy or inflammatory and infectious diseases of the retina. Tumors in the retina or choroid can also present with an accompanying serous retinal detachment.
Often, serous retinal detachments are treated by addressing the underlying cause of the subretinal fluid, though there are cases when serous detachments of the retina need to be surgically drained.