Even among the small number of ophthalmologists who specialize in pediatric retina, consensus hasn’t emerged on whether, how, or when eyes with stage 5 retinopathy of prematurity (ROP) should undergo surgery. At issue is the poor anatomical and visual prognosis of stage 5, which is characterized by total retinal detachment in the shape of a closed funnel.
Early in my career, when I first began treating children with ROP, I performed surgeries in stage 5 cases but stopped for a period of time, believing that the procedures weren’t accomplishing much. However, months and even years later I had opportunities to reexamine many of the children on whom I had operated and many I hadn’t. Comparing the two groups, I saw the benefits of light perception vision that the surgeries had accomplished. The children’s parents and families often told me how significant it was in their lives. Light perception allows the children to know whether it’s day or night and whether to sleep or wake. It also allows them to better orient themselves as they perceive their surroundings, for example, a nearby door or window. For children who have never been able to see details, this type of vision helps them to ambulate and orient themselves to time and space. Once that became clear to me, I reversed my previous decision and began performing the surgeries again (Figure 1).
Indications for Surgery
Knowing how important light perception can be for a child with ROP, I’m usually inclined to recommend surgery in cases that have progressed to stage 5. I do, however, consider a decompensated cornea a contraindication. Other surgeons may disagree, but in cases where the detached retina has pushed the lens forward into the cornea and decompensated the tissue, I personally don’t think putting the eye through a vitrectomy as well as a cornea transplant is beneficial. While cases this advanced are less and less common in the United States, I see them relatively frequently when patients come from other regions, such as Latin America, the Middle East, or Asia. In many developing countries, awareness of ROP among ophthalmologists and pediatricians remains low. As long as a patient with stage 5 disease reaches me before the cornea decompensates, I believe operating on both eyes or at least one eye is beneficial.
Surgical Goals and Challenges
Because the retina is completely detached in stage 5 ROP, the goal of surgical intervention is to achieve at least partial reattachment. This may enable light perception, and it may also prolong the survival of the eye itself by preventing phthisis. Because of the neovascularization and fibrovascular proliferation that has occurred in stage 5 ROP eyes, the funnel retinal detachments are typically tractional rather than rhegmatogenous. The more vitreous that can be released during surgery, the more likely at least some of the retina will reattach.
I perform a three-port procedure, entirely through the limbus, using 25-gauge short instrumentation. Because of the detached retina’s push forward, the anterior chamber can be quite shallow. Once the chamber is infused, I usually use viscoelastic to help stabilize it. I like to enlarge the iris by cutting it with the vitrector. This prevents complications from adhesion or pupillary synechiae. Next, I perform a lensectomy, removing the lenticular material and the entire capsular bag.
The challenge at this point is determining where to begin removing the sheath of vitreous that has formed in a circumferential and radial pattern and closed the funnel anteriorly. Failure to find the correct plane for opening the funnel and unintentionally engaging retinal tissue renders the surgery a failure. Often, it’s necessary to dissect several layers of membrane to open the funnel. Once inside the funnel, the goal is to remove as much vitreous and membranes as possible without creating a rhegmatogenous component. Once a rhegmatogenous component occurs, the surgical success drops significantly. At the end of a successful case, I like to instill viscoelastic for stabilization and rigidity for closing the eye. At the end of surgery, the retina is opposed to the scleral wall; therefore, laser is not possible or recommended. With time, once the traction is removed, the retina reattaches without the need for vitreous substitutes.
For these cases, I like to use the Constellation Vision System (Alcon) with very few instruments other than the vitrector and the needle of the trocars. A 25+ Short vitrectomy pack (Alcon), designed specifically for small eyes, is now available. It includes a stiffer, shorter probe (18 mm) and an endoilluminator (14 mm). The shorter, stiffer probe is very helpful, especially when performing anterior work. Working in such small eyes, with limited exposure and space for instrumentation, the stiffness and shortness of the instruments works to the surgeon’s advantage. In such small eyes, longer, more flexible instruments are difficult to control and they tend to crowd the eye, bend, and interfere with the viewing system.
Following surgery for stage 5 ROP, I recommend that dorzolomide eyedrops be instilled twice a day for IOP control. I also prescribe atropine to be used twice a day. After the initial postoperative visits at 1 day and 1 week, I like to see patients every 6 months to monitor whether the retina is flattening and check for potential problems, which may include redetachment, vitreous bleeding, or secondary glaucoma. I like to document the progress with digital retinal photography in clinic.
A Difficult But Important Surgery
For surgeons who haven’t operated on stage 5 ROP eyes, it’s difficult to conceptualize how the surgery can actually lead to a flattening and reattachment of the retina and the capability of light perception. Given my practice focus and location, I’ve been able to follow many of my post-op patients for many years. Being in practice for 17 years in Miami has allowed me to see the visual development of these patients. Seeing the results, I’m confident that had I not done something for these children, most would be in complete darkness. ■