It has been noted in various studies that scleral sutures become necessary in case of incompetent sclerotomies even after wound massage when undergoing 23G vitrectomy.15 These sutures may lead to higher incidence of post operative astigmatism.16 This surgically induced astigmatism is temporary and usually returns back to preoperative values at four months post op.17,18
Such port leaks may lead to hypotony, infections, choroidal detachments and loss of effective tamponade.22,23 Surgeons are now more keen to apply sutures to visibly incompetent sclerotomies even with smaller gauge vitrectomies to avoid these potential complications.
Modified 20 gauge sutureless single step sclerotomies for pars plana vitrectomy.
(9.) Theelen T, Verbeek AM, Tilanus MA, van den Biesen PR.A novel technique for self-sealing, wedge shaped pars plana sclerotomies and its features in ultrasound biomicroscopy and clinical outcome.
Eckardt10 in 2005 introduced 23 gauge TSVS which offer angled self sealing tunnel sclerotomies
maintained through trocar canulae throughout surgery period.
Standard 20G vitrectomy surgery requires conjunctival incisions and sclerotomies of 0.89 mm diameter.
Placing the sclerotomies closer to the horizontal meridian reduces the need to rotate instruments significantly for peripheral and superior access and avoids displacement of the infusion as the eye is rotated inferiorly .
Microincisional scleral tunnel entry radial to the limbus leaves more room for future sclerotomies than conventional 20G incisions running parallel to limbus, preventing coalescing of wounds in repeat surgeries.
Valved cannulas address the problem of high flow from the infusion through open cannulas during instrument exchange due to IOP compensation features, which can lead to a "fountain effect" at the open cannulas and dislodge plugs, or cause vitreous or retinal incarceration at the sclerotomies .
A spectral-domain OCT system (RTVue, Optovue Inc., Fremont, CA) with a corneal adaptor module (CAM) was used to image the sclerotomies on postoperative days 1, 7, and 30.
Thirty 25-gauge sclerotomies of ten eyes and thirty-six 23-gauge sclerotomies of 12 eyes were analyzed.
Chen first described sutureless self-sealing sclerotomies in 1996 .