A 57-year-old female with a past ocular history of degenerative retinoschisis presented complaining of seeing a “pop of ink” and flashes in her right eye vision starting 1 week prior with a progressive increase in floaters. Right eye (OD) clinical exam revealed a Snellen visual acuity (VA) of 20/40, inferotemporal visual field defect by confrontational exam, and mild nuclear sclerosis on anterior segment exam. Posterior segment exam showed a superotemporal retinal detachment subtending approximately 4 clock hours and extending posteriorly within the superior vascular arcade, with visible inner retinal holes peripherally at approximately 2-o'clock and outer retinal hole more posterior to these. Left eye (OS) exam was unremarkable with VA of 20/20. Optical coherence tomography (OCT) of the right macula showed an extended retinal detachment within the arcades and attached fovea (Figure 1A). Surgical treatment options were discussed, and the patient elected to proceed with cryotherapy and PR. The patient was prepped and draped in the minor procedure room. Subconjunctival injection of lidocaine 2% with epinephrine 1:10,000 was given superonasally and superotemporally for local anesthesia. Transscleral cryotherapy was applied to the inner and outer retinoschisis breaks. Intravitreal injection of SF6 gas (0.6 mL of 100% concentration) was introduced through the superotemporal quadrant, followed by anterior chamber paracentesis using a 30-gauge needle on a TB syringe. Optic nerve head perfusion and a single gas bubble present in the vitreous cavity were confirmed by indirect ophthalmoscopy. The eye was patched, and the patient maintained a face-down position for 6 hours before repositioning in a “steamroller” technique to bring the gas bubble against the inner retinal breaks. At the 1-week postoperative visit, VA OD was 20/60, intraocular pressure (IOP) was 12 mm Hg, and on exam, the retina was attached with 20% to 25% gas bubble fill (Figure 2A). At the 1-month postoperative visit, the gas bubble was fully resorbed, and the retina remained attached (Figure 2B). At the 4-month visit, VA OD was 20/30, and OCT showed healthy foveal contour with distinguished retinal layers (Figure 1B).
(A) Optical coherence tomography (OCT) demonstrating extended retinal detachment within the arcades and attached fovea on initial presentation. (B) OCT demonstrating healthy foveal contour with distinguished retinal layers at the 4-month postoperative visit.
(A) Widefield fundus photo of the right eye (OD) at the 1-week postoperative visit demonstrating attached retina and approximately 20% to 25% gas bubble fill. (B) Widefield fundus photo OD at the 1-month postoperative visit demonstrating attached retina, chorioretinal scar corresponding to cryotherapy treatment area, resolving vitreous hemorrhage, and fully resorbed gas bubble.
Retinoschisis-related retinal detachment can be a challenging condition to repair surgically. Some authors prefer a scleral buckle technique with or without SRF drainage or cryotherapy to repair associated retinal breaks,8 whereas others prefer to proceed with PPV where a retinotomy may be needed if the inner and outer retinoschisis breaks are not apposing each other.6,9 Stem et al. reported a single-surgery success rate of 65% for repair of this condition using scleral buckle, vitrectomy, or a combination of both, without PR.3
Cryotherapy for retinal detachment is applied to the sclera overlying the area of retinal breaks to create chorioretinal inflammation, whereas PR is a minimally invasive procedure that utilizes a gas bubble injected into the vitreous cavity to occlude the retinal break. For this technique to be effective the gas bubble must remain positioned correctly long enough for the retinal breaks to form chorioretinal adhesion and scarring.10 Animal studies have shown that a strong chorioretinal scar may need up to 1 week to form when using cryotherapy.11
In select patients, authors reported successful repairs of retinoschisis-related detachments by various techniques including cryopexy, SRF drainage, and intraocular gas injection,9 whereas some may add suturing of the sclera at the injection site.12 The proposed minimally invasive technique does not include drainage of SRF, thus avoiding the associated risks of iatrogenic full thickness retinal breaks, subretinal hemorrhage, and retinal or vitreous incarceration at the drainage site. In addition, it can be performed in a minor surgical procedure room, which minimizes the health system resources needed for the repair.
Other investigators proposed treating the inner retinal break with transscleral cryotherapy and injection of filtered air, then treating the outer retinal break with laser photocoagulation the following day.13 Knowing that air bubbles usually resorb quickly (< 6 days), patients may have increased risk of retinal redetachment if the outer retinal breaks are not treated properly the following day with laser due to poor view, ferning of the natural lens, or persistent SRF preventing laser uptake. We propose cryotherapy for both outer and inner retinal breaks in the same session since the patient is already undergoing the procedure and the use of SF6 gas instead of air, which will allow enough time for SRF to resorb and for a strong chorioretinal scar to form.
Suzuki et al. reported a repair of progressive retinal detachment in senile retinoschisis with PR using perfluoropropane (C3F8) gas and closing the retinal tears with argon laser 2 days after the gas injection.14 However, retinal breaks can be easily missed when viewed through the gas bubble once the retina is flat. The proposed technique utilizes cryotherapy which may allow for better delineation of retinal breaks margins, as well as a simpler single-day procedure. In addition, this technique utilizes SF6 gas, which forms a larger bubble as compared to C3F8 gas, allowing for larger steamrolling if needed and better early coverage of the targeted outer and inner retinal breaks to ensure SRF resorption. It lasts long enough to allow time for chorioretinal scar formation compared to air, but resorbs sooner than C3F8 gas, which avoids the increased risk associated with induced vitreoretinal traction.
Selection criteria for a successful outcome with this technique include: 1) retinal detachment with superiorly located retinal breaks, 2) no proliferative vitreoretinopathy present, 3) patient's ability to maintain the required head position, and 4) the ability to manage possible complications, including retinal redetachment, increased IOP, and endophthalmitis. Additionally, although not required, the presence of a detached posterior hyaloid is preferred to minimize the risk of inducing new retinal breaks.
A limitation of this technique includes the risk of epiretinal membrane formation associated with cryotherapy.15 Acceleration of cataract formation is another limitation known to occur with intravitreal gas presence.10 In addition, anterior chamber tap in phakic patients may be complicated with iatrogenic cataract if the needle touches the anterior lens capsule.
In conclusion, this minimally invasive technique, when combined with proper patient selection, may offer complete repair in a single session, and minimize treatment burden in treating retinoschisis-related retinal detachment.