Many cases of stage 4 ROP will decompensate over time and develop into complex combined traction and rhegmatogenous retinal detachments. Needless to say they are tough to fix. They do not respond to the usual techniques for other combined retinal detachments. In my practice I see many cases after multiple failed surgeries. The standard of care is followed and it is commonly a failure because of surgical rule #2. (This comes from being a fellowship mentor for too many years) Surgical techniques developed and refined within the context of one disease or pathologic condition give unpredictable results when applied to a different disease.
I thought I might share my hard won techniques developed in treatment of late ROP because they are my best. I hope that they help. Feel free to ask more details about what is unclear. Regarding technical proficiency, I assume the surgeon is well experienced with high intensity combined cases from diabetes, PVR and trauma. Surgical brilliance at the 23ga and 25 ga cases that are fun do little to prepare the surgeon technically in this because they are overly specialized and refined for other diseases. For example the range of instruments and surgical maneuvers are limited. I really do love ERM, primary retinal detachment, macular hole, vitreous hemrrhage etc., but infact, the approaches for late ROP are very different then the usual surgical retina case. The location of pathology is peripheral, primary avascular retina is different even from proliferative sickle-cell disease, the growth of fibrous proliferation from the retina vessels is similair to diabetes, the vitreous attachments are quite variable. Most confusing is that the endpoint is different.
Adult ROP is a very important part of my practice. All eyes with fibrous residua are at increased life-long high risk of retina detachment and need to be monitored at least 3-4 times annually. There are a few issues: first, how to treat the rd; second, how to prevent the rd; third, the post-cataract surgery risk; fourth, dwindling vision from chronic detachment; fifth, navigating risk of residual TRD. I will deal with the first issue in this post. Even this is a work in progress and I expect to revise parts in the coming weeks.
Observations:
Minor TRDs away from the macula may be stable for a long period and should only be approached with extreme care, and only when the risk of surgery is less than the risk of observation. Check out the post on treatment decisions.
Late ROP is not like PVR because the membranes do not peel off and the vitreous can be quite tightly adherent. The subretinal membranes also are much tighter.
Late ROP not like typical TRD in PDR because the fibrous proliferation has broader connection and cannot be completely removed. Also the avscular retina anteriorly may stetch and break. Aggressive removal will leave a difficult combination of breaks and residual traction which is unstable.
The surgery for late ROP is similair to 1970s or early 1980s TRD surgery when there was no laser and you needed to release traction and allow the retina to relax and reattach.
#1 The traction cannot be completely removed
#2 Retinectomy will result in failure from hypotony
#3 Retinotomy may be impossible to free of vitreous or fibrous proliferation and cause failure
#4 This should not be treated as a night case emergency by the surgeon on call.
The key to my success comes from doing the least amount of surgery possible and considering incremental surgery over weeks depending on the retinal response instead of jumping into the mode of "extreme vitreous surgery". LESS IS MORE for this group. This is tricky since the only hard endpoint, a completely flattened retina, is likely to lead to failure. Inexperienced surgeons may be confused because soft endpoints that are difficult to identify. The correct endpoint is adequate retinal mobilization and closure of the break.
Option 1: If there is an identifiable break that is treatable with a buckle, a purely external scleral buckle will yield an excellent result. Personally, I strongly prefer nondrainage scleral buckles, but I would assume drainage is fine as long as it is uncomplicated.
Unfortunately such a break is not discovered. I presume it to be peripheral just beyond or posterior to the junction of the vascular and avascular retina or along the area of traction from the residual anterior traction. Try Option 2
Option 2:
A. I place an equatorial band #240 around the eye.
I prefer sutures not belt loops because these eyes are categorized as abnormal and I am unsure about the scleral integrity and thickness.
B. Examine the anterior retina to find an entry site that will avoid the lens and the anteriorly dragged retina. I will place my ports wherever it is safe. It is a balance between ease of surgery and safety.
If needed, open the pupil with hooks without removal of the crystalline lens to find safe entry. The lens is really good to keep if at all possible
My favorite sclerotomy distribution for difficult cases is superior temporal infusion and directly temporal active port and superior nasal active port. This gives a large angle between the instruments and best access to the superior retina. But sometimes the sclerotomy placements are all nasal, superior or whatever. My sclerotomy location can be anywhere from 1-3.5 posterior to limbus. Keep the lens in place, if you are in contact with the lens try to pressing movements against the lens rather than stabbing or shearing movements.
Use the Volk quadrasperic lens and a diffusion light pipe attached to a bright light source to get the best peripheral view. The BIOM limits the peripheral view by a critical 20 degrees in these cases, so you need an excellent assistant. The light pipe allows viewing in the zone of the lightpipe sclerotomy and is an excellent improvement in viewing. Use of the directional light does reveal vitreous strands and may be helpful.
Again, avoid lensectomies because the intact zonule and crystalline lens significantly reduces complications from oil filled vitreous.
I enter carefully with a curved scissors and do limited safe fibrous tissue and condensed vitreous laminectomy. I prefer the Synergetic or DutchOphthalmic curved scissors. I rather leave traction than cause a break. Mild surgery can be followed by an increment without much problem, but aggressive surgery sets-off a oozing of fibrin and membrane proliferation that compounds the complexity. Breaks are poorly tolerated.
I avoid retinotomies or retinectomies, but flatten the retina as much as possible with air-fluid exchange (or PFO) and then fill the vitreous with oil. If the retina is pretty flat one can use the infrared laser with low energy and long duration to get uptake deep (less than 450 mw is usually safe but this is just experience based) whitening is not needed
Since there is no obvious subretina drainage the retina may not be flat at the end of the case and laser may not done. That is for later after the RPE pump removes the rhegmatogenously related subretinal fluid. The goal is just to get back to better not to flatten the retina. The oil is like the gas bubble in pneumatic retinopexy.
Keep the closing pressure soft around 5 mm hg
I often insist on face down position for a week; except for transport, food and toilette. The TV, computer and games can be used in face down position.
I treat the pressure and wait for attachment. I do EUAs frequently to get a high quality exams to treat imperfections and treat with laser 360 degrees (again infrared at long duration low energy when the retina attaches).
If the minimalist approach fails after a couple months I will consider more aggressive approach, but the best results are definitely with minimal intervention.
Subretinal bands in these cases are left alone initially because they are very tightly adherent in many cases and relax over time if not too close to a break.
If the kid develops a cataract I try to not treat it until the retina is attached and laser is complete. When laser is complete and confirmed I wait 3 months for laser adhesion maturation
Sometimes there is severe posterior synechia and high pressure, then I ask a glaucoma person to laser in a PI.
Option 3:
More Aggresive surgery:
The lens must be removed occasionally, and post-op the inferior PI of Ando often closes because of fibrin. I use high dose systemic steroids for 4 days and lots of drops. Facedown position. I warn the parents that the kid might get strange with high dose steroids and to tolerate the edginess.
Retinotomy may be needed. Preventing air from going into the subretinal space in the face of an incompletely relesed traction near a retinoctomy may be accomplished using a technique I saw visiting Dr H Kono and H. Hayashi in Fukoka, Japan. A barier of healon is place over the break prior to the completion of the air-fluid exchange and the excahnge is completed with low air pressure with an effort to minimize displacement of the Healon then oil is instilled.
Retinectomies may be needed and they require surgical maintenance because of the fibrin which leads to traction develops at the edge. Hypotony and long-term silicone oil becomes likely, prognosis is now poor.
Falciform fold cannot be opened and flattened they can be freed peripherally and pressed down, the fold can be treated with laser through the double leaf of retina and will frequently adhere.
This is a new topic for me and I would appreciate the comments of colleagues.
My heartfelt wishes to all the patients and surgeons. I hope my advise is helpful and reduces suffering.
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