This pilot clinical study preliminarily demonstrated that FCB scleral buckling is a feasible treatment alternative for retinal reattachment in some complex RRD cases when patients refuse PPV surgery. Considering a previous exploratory clinical study that used this technique to treat simple RRD, we suggest that FCB scleral buckling may represent an innovative surgical method to improve general RRD management .
From the postoperative examination results of five patients, it is clear that external FCB exerted pressure on the sclera and retina, and that its location was not easily changed by ocular movement during the postoperative observation period. Combined with subretinal fluid release, transscleral cryotherapy, and retinal photocoagulation, FCB scleral buckling surgery greatly improved the BCVA of the five patients compared to before surgery, indicating that this innovative surgical method supports retinal reattachment and restores function. The retina was successfully reattached after surgery in all the patients.
For Patient 2, postoperative examination showed a small amount of subretinal fluid in the upper peripheral fundus; therefore, we conducted intravitreal gas injection on the tenth postoperative day to promote close attachment of the retina. The second day after intravitreal gas injection, the retina was fully reattached. Postoperative OCT of Patient 5 showed that the neuroepithelial retina was still slightly detached, which may be due to the patient’s long period of retinal detachment, viscous subretinal fluid, and severe PVR proliferation cord. However, a relatively common scenario in patients who undergo retinal reattachment is the slow absorption of viscous subretinal fluid and full reattachment. Considering the severe retinal detachment in all five patients, combined with the special case of high myopia, intraocular lens, or PVR, we show that FCB scleral buckling is effective in the treatment of complex RRD.
None of the five patients experienced severe adverse events, such as endophthalmitis, cardiovascular events, or other systemic reactions. Moreover, there were no acute high IOP events caused by FCB scleral buckling, nor were there episodes of severe postoperative bleeding or extreme discomfort. However, it should be noted that Patient 3 developed diplopia after the operation, which did not resolve after fluid was released from the FCB, but continued until the FCB was removed. This may have occurred because the FCVB influenced the extraocular muscles, especially since it was located under the rectus in accordance with the patient’s retinal detachment and hole location. However, the complication was resolved by removing the FCVB, indicating that its influence on the extraocular muscles is reversible. Because the FCB balloon is not continuously implanted under the conjunctiva, diplopia may occur in some patients, but with the removal of the balloon, this issue will resolve. Therefore, with these few complications and using the 3/n rule, we are confident that the true complication rate of FCB scleral buckling is no more than 60% .
FCB scleral buckling is an improvement of traditional external scleral surgery, compared to which it might possess advantages and avoid some shortcomings. In external scleral surgery, the fundus image is inverted through an indirect ophthalmoscope and the magnification is small, making it difficult to perform and master. In addition, post-eyeball anesthesia is needed to increase the risk of puncturing the eyeball. Moreover, the sclera needs to be exposed by repeatedly pulling the muscle, thus inducing pain in the patient and introducing a high risk of the occurrence of the oculocardiac reflex. In contrast, in FCB scleral buckling, all these procedures are conducted under a microscope and involve fewer muscles, making it less invasive and easier to perform. Only Patient 2 in this study received local surface infiltration anesthesia, which may indicate that this surgery is especially suitable for the elderly, young children, nervous patients, patients in poor health, and even pregnant women.
This type of surgery also has a larger pressure range, usually covering the hole and surrounding the detached retina. Although the spherical pressure generated by the FCVB and its indwelling time can be controlled, we tentatively used FCB scleral buckling to treat some complex RRD patients, although these patients should have received PPV surgery but refused. As a type of external scleral surgery, FCB scleral buckling has the common advantages of external scleral surgery and could avoid some disadvantages of PPV surgery, such as increased risk of PVR and epiretinal membranes as well as low oxygen distribution in the vitreous, which could further accelerate cataracts in phakic eyes and damage trabecular meshwork cells [11–16]. FCB scleral buckling could also avoid optic nerve atrophy, disruption of ciliary body secretion induced by silicone oil injection, and other complications caused by PPV surgery [13, 22–29].
This study showed that FCB scleral buckling can be a feasible, effective, and safe alternative to retinal reattachment in some complex RRD cases when patients refuse PPV surgery. However, certain shortcomings of this surgery should not be neglected: it is relatively difficult to fix if the FCVB is located under the muscle, and patients with an FCVB are at risk of developing temporary diplopia, although this can be relieved by releasing some water from the balloon. Additionally, the current study design has some limitations, notably a small number of subjects, lack of a control group, and no comparison with conventional treatment strategies. Accordingly, a large-scale randomized study controlled with PPV should be conducted to further confirm the efficacy and safety of FCB scleral buckling.
In summary, this study showed that FCB scleral buckling is a simple, easy to learn, less invasive, and less complicated alternative for treating some complex RRD cases when patients refuse PPV surgery. These promising results grant us the confidence to conduct large-scale multicenter clinical trials to further verify the efficacy and safety of FCB sclera buckling.