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Hypotony-Free Closure of Infusion Sclerotomy Using a Slit-Modified Trocar in 23-Gauge Vitrectomy for Proliferative
Goran Marić1, Danny A Mammo2, Ante Vukojević1
1Department of Ophthalmology, University Hospital Center Sestre Milosrdnice, Vinogradska Cesta 29, 10000 Zagreb, Croatia.
Purpose:
The aim of this study is to describe a slit-modified 23-gauge infusion trocar designed to enable early postoperative hypotony-free sclerotomy closure by allowing scleral suturing prior to complete trocar removal, and to report initial clinical outcomes in eyes with proliferative diabetic retinopathy with or without vitreous hemorrhage (PDR + H and PDR).
Methods:
A standard 23-gauge metallic (titanium) trocar was modified by creating a longitudinal slit that permitted passage of a suture needle while the trocar remained partially engaged within the scleral tunnel. At the end of pars plana vitrectomy, a transscleral suture was placed through the slit with the knot prepared prior to trocar removal, followed by simultaneous trocar extraction and suture tightening. Eighteen consecutive patients undergoing vitrectomy for PDR (fourteen with vitreous hemorrhage [PDR + H]; four without) were included. Intraocular pressure (IOP) was recorded preoperatively, immediately after sclerotomy closure (postoperative baseline), and at 8 and 24 h postoperatively. The study was designed as an exploratory pilot feasibility and safety evaluation of a slit-modified infusion trocar in 23-gauge vitrectomy. The primary outcomes were postoperative IOP stability and wound leakage. Secondary outcomes included early hypotony, postoperative hemorrhage, choroidal effusion, and the need for additional suturing.
Results:
All procedures were completed without intraoperative complications. The mean IOP was 14.83 ± 2.50 mmHg preoperatively, 13.33 ± 1.53 mmHg immediately after closure, 14.17 ± 3.01 mmHg at 8 h, and 15.17 ± 1.79 mmHg at 24 h. No cases of wound leakage or early postoperative hypotony were observed in either subgroup. One eye exhibited a transient IOP increase at 8 h; no choroidal effusion, postoperative hemorrhage, or need for secondary suturing occurred. Endotamponade consisted of balanced salt solution (BSS) in eight eyes, SF6 in seven eyes, silicone oil in two eyes, and air in one eye.
Conclusions:
The slit-modified infusion trocar enables secure, hypotony-free closure of the infusion sclerotomy by eliminating the open-wound interval during trocar removal. This simple biomedical device modification provides stable early postoperative IOP across different tamponade agents and appears safe and feasible in high-risk eyes with PDR.
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