Miyake-Apple view of inner side of sclerotomy during microincision vitrectomy surgery

Abstract

. Purpose: To examine the inner surface of the sclerotomy during microincision vitrectomy surgery by Miyake‐Apple view. Methods: The anterior half of porcine eyes was attached to a transparent acrylic plate with cyanoacrylate glue. Then, either a 23‐gauge or a 25‐gauge trocar‐cannula was inserted through the sclera obliquely. The inner surface of the entrance site was observed posteriorly by Miyake‐Apple view. These images were compared with the endoscopic view of two patients who underwent vitreous surgery for an epiretinal membrane. Results: When the trocar‐cannula was inserted obliquely, the Miyake‐Apple view showed that the ciliary epithelium at the sclerotomy site was stretched. When the trocar‐cannula was inserted vertically, the ciliary epithelium was folded, and the folds remained even after the trocar was removed. Vitreous strands were seen incarcerated into the sclerotomy site. In human eyes, a folding of the ciliary epithelium was not clearly seen with the endoscopic view but the incarcerated vitreous was seen. Conclusion: The Miyake‐Apple view provided a precise, in vivo, observation of the inner surface of the entry site. It disclosed the morphological stress on the ciliary epithelium by the sclerotomy.

Influence of the Interposition of a Nonhollow Probe during Cannula Extraction on Sclerotomy Vitreous Incarceration in Sutureless Vitrectomy

“…In fact, we found vitreous strands in practically all the sclerotomies analyzed (93.2% and 95.8%, depending on the incisional subgroup evaluated), as had been previously described by other studies that used an endoscopic video probe 10 or an external video camera system (MiyakeApple exploration). 11 Therefore, regardless of the element inserted through the cannula during its extraction, and in spite of performing intense vitreous shaving around the incision sites during the operation, it was not possible to leave the perisclerotomy region free of vitreous in almost any sclerotomy after the vitrectomy. This high rate of vitreous incarceration may be caused by the inserted cannulas, which protrude 2 to 3 mm into the vitreous cavity, possibly impeding complete clearing of the vitreous that surrounds the cannula.…”

“…Nevertheless, our results are similar to those observed in human research. 10,11 The important outcome of our study is the relative difference in vitreous entrapment grade detected in sclerotomies whose cannulas were extracted with the light pipe or the plug inserted.…”

“…2,3 Since the implantation of the TSV, numerous studies have analyzed different aspects of the sclerotomies such as the presence of incisional vitreous incarceration. [4][5][6][7][8][9][10][11] This vitreous entrapment may work as an incisional plug, favoring postoperative sclerotomy closure; however, it has been also related to some postoperative complications, such as peripheral retinal tears as a result of postoperative vitreous contraction, [12][13][14] acute endophthalmitis due to the presence of incisional vitreous wick that may facilitate the entry of bacteria into the vitreous cavity, 15 and fibrovascular proliferation that is considered a major risk factor for recurring vitreous hemorrhage in diabetic patients. 16 Previously, some authors have described different maneuvers aimed to reduce this postoperative vitreous incarceration.…”

Intraoperative endoscopic observation of sclerotomy site after cannula removal for 23-gauge vitrectomy

“…Reported incidence rates for vitreous incarceration at the sclerotomy site of microincision sutureless vitrectomy are variable 11,13,24,28–33. Using ultrasound biomicroscopy, Gutfleisch et al30 reported that the incidence of vitreous incarceration decreased from 40% to 20% at the sclerotomy sites using a 23-gauge two-step system compared with a sclerotomy site using a 23-gauge one-step system; in their study, the cannulas were simply removed.…”

“…In a study of sclerotomy sites in rabbits,32 vitreous incarceration occurred in 59.4% of cases. Inoue et al33 found vitreous strands incarcerated at the sclerotomy site in porcine eyes by Miyake-Apple view and in human eyes using endoscopy. These inconsistencies in incidence rates for vitreous incarceration may be due to the different surgical techniques used and the differences between human eyes and experimental models.…”