Local dry vitrectomy combined with segmental scleral buckling for the management of rhegmatogenous retinal detachment with vitreous traction

Purpose: To demonstrate combined local dry vitrectomy and segmental scleral buckling for the (RRD) with vitreous traction in patients at high-risk for proliferative vitreoretinopathy (PVR). Methods: Seven eyes of 7 patients were retrospectively studied, including 3 retinal dialysis, 3 retinal detachment (RD) with peripheral retinal holes and 1 RD with giant tear. All patients exhibited local vitreous traction and a high risk for PVR. Dry local vitrectomy without regular infusion was performed to remove the vitreous traction. Viscoelastic fluid was injected into the vitreous cavity if needed. Segmental scleral buckling was performed accordingly. Demographic information, preoperative and postoperative complications, and outcomes were recorded. Results: The mean age of the patients at presentation was 22.43±14.28 years old. All seven patients obtained retinal reattachment after a single surgical intervention. Postoperative visual acuity was improved in all patients. None of them developed complications, except for temporary mildly increased intraocular pressure in 2 cases. Conclusions: Combined local dry vitrectomy and segmental scleral buckling is effective for patients of RRD with local vitreous traction. The technique avoids many complications associated with regular surgery and was minimally invasive to both the external and internal eye.


Background
Rhegmatogenous retinal detachment (RRD) can be surgically treated using scleral buckling, and/or pars plana vitrectomy (PPV). In patients at high risk for proliferative vitreoretinopathy (PVR) with RRD caused by vitreous traction, performing segmental scleral buckling alone poses a significant surgical challenge because persistent vitreous traction may lead to failure of the surgery [1]. However, regular vitrectomy has some potential complications, such as cataract, especially in young patients.
Vitrectomy surgery may result in more diffuse vitreous-base disruption if the vitreous base is shaved over the peripheral retina and pars plana during aggressive vitreous removal [2]. The objective of this article is to introduce a modified technique that combines local dry vitrectomy (without regular infusion) and segmental scleral buckling, and to demonstrate the applicability of managing RRD with local vitreous traction in patients at high risk for PVR, especially young patients not suitable for regular vitrectomy.

Patients and Methods
Institutional review board approval was obtained for this retrospective review. The indications for this combined surgery were partial rhegmatogenous retinal detachment with local vitreous traction around the retinal hole or tear with preoperative PVR B. No one had posterior vitreous detachment (PVD) preoperatively. The following situations would be considered but not mandatory when making the decision, such as young age, macula-on status, good preoperative visual acuity of the operated eye and poor visual acuity of the fellow eye. All surgeries were performed by one surgeon (P.Z.). All patients underwent a comprehensive ophthalmic examination before surgical intervention, including clinical history, review of systems, measurement of best-corrected visual acuity (BCVA) and intraocular pressure (IOP), fundus photography, B scan, slit-lamp, and indirect biomicroscopy. The informed consent was obtained from all participants or his/her legal guardians if under 18 years.

1.
Conjunctival incision for segmental scleral buckling was made according to the range and location of the retinal breaks. If the retinal hole was small, minimal in situ radial conjunctival incision (5 to 6 mm) would be made [3]. If the retinal break or dialysis was extensive, the conjunctiva would be dissected at the limbus accordingly. Transconjunctival traction sutures were placed under the rectus muscles.

Discussion
Surgical approaches for low-to-moderate complexity RDs have been well studied [1,4,5]. The most common cause of surgical failure in RRD is PVR. However, less is known about surgical outcomes in patients at high risk for PVR. This study presented a new technique involving combined local dry vitrectomy and segmental scleral buckling in RRD patients with local vitreous traction and a high risk for PVR.
Scleral buckling is an ophthalmic surgical technique that has been successfully used to repair RRDs for over 60 years. Scleral buckling has an important role in the repair of certain categories of RRDs.
These include detachments in young phakic patients, detachments associated with dialysis, and also in conjunction with vitrectomy in patients who sustain trauma or have developed PVR [6]. However, in patients of RRD with vitreous traction, who are also at high risk for PVR, performing segmental scleral buckling alone poses a significant surgical challenge because persistent vitreous traction may lead to failure of the surgery. For patients at high risk for PVR, PPV-scleral buckling has been associated with significantly higher rates of anatomical success compared with PPV alone [1].
Combining local dry vitrectomy and segmental scleral buckling were performed in these eyes. It has been established that vitrectomy is a risk factor for complicated cataract surgery and IOL dislocation. The main cause for nuclear cataracts after vitrectomy most probably is oxidative stress.
Oxygen in the avascular lens is provided by diffusion, meaning that the surrounding oxygen content is crucial for the oxygen content within the lens. The partial oxygen pressure is highly elevated in the . None of our patients has experienced a complicated postoperative cataract, which has a high incidence in patients after regular vitrectomy [2]. This is especially important in young patients.
However, two patients exhibited mildly increased IOP one to two weeks postoperatively (cases 3 and 4), which returned to normal two to three weeks after the operation. When performing dry vitrectomy, viscoelastic solution was injected to maintain IOP instead of the regular infusion to avoid overly disturbing the vitreous. The reason for the temporarily increased IOP may be due to the migration of the viscoelastic solution from the vitreous cavity into the anterior chamber via the fragile zonule. The IOP may return to normal after the absorbance of viscoelastic solution.
Limitations of this study include a relatively small sample size and its retrospective design.
Moreover, this was only a single surgeon's experience and, therefore, the results may not be universally applicable. A larger prospective cohort study involving multiple surgeons would be needed to assess the true success and complication rates of this technique.
In summary, combined local dry vitrectomy and segmental scleral buckling was a highly successful method of managing RRD with local vitreous traction in patients at high risk for PVR, especially in young patients. Careful preoperative and intraoperative planning should be undertaken to achieve minimal invasiveness and the best postoperative visual results.