Department of Ophthalmology, University Hospital Principe de Asturias, Alcalá de Henares (Madrid), Spain.
Invest Ophthalmol Vis Sci. 2013 Jun 26;54(6):4366-71. doi: 10.1167/iovs.13-12008.
To evaluate the influence that vitreous incarceration may exert on the presence of postoperative conjunctival blebs over sclerotomies after transconjunctival sutureless vitrectomy (TSV). Blebs are formed by incisional leakage due to incompetent closure.
Experimental study in which 23-gauge TSV was performed in 146 cadaveric pig eyes. Once the vitrectomy was finished, triamcinolone was injected inside the vitreous cavity for staining residual vitreous, one of the superior cannulas was extracted over the light probe, and the other cannula was removed with the plug inserted. Postoperative conjunctival blebs in superior sclerotomies were assessed by anterior-segment optical coherence tomography (AS-OCT) in a masked fashion; nondetectable blebs were classified as grade 0 (B0), thin bleb (≤half scleral thickness) as grade 1 (B1), and thick bleb (>half scleral thickness) as grade 2 (B2). Postoperative incisional vitreous entrapment was evaluated by slit-lamp photographs in a masked way; no incarceration was classified as grade 0 (V0), thin incarceration as grade 1 (V1), and thick incarceration as grade 2 (V2).
Conjunctival blebs were found in 13.7% of the sclerotomies (11.3% bleb-B1, 2.4% bleb-B2). Vitreous incarceration was found in 96.5% of the sclerotomies without bleb (B0), 81.8% of the incisions with bleb-B1, and 14.3% of the wounds with bleb-B2. Vitreous incarceration was significantly associated with the absence of conjunctival bleb (P < 0.001).
Vitreous incarceration in sclerotomies is related to less incisional leakage in our experimental model. Maneuvers that reduce vitreous entrapment, such as the interposition of a nonhollow probe during the cannula extraction, could decrease the sclerotomy closure competency.
评估玻璃体嵌顿对经结膜无缝合玻璃体切除术后巩膜切口处术后结膜泡形成的影响。结膜泡是由于切口漏液导致闭合不全而形成的。
本实验研究采用 23 号穿刺套管进行了 146 例猪眼尸体的经结膜无缝合玻璃体切除术。玻璃体切除完成后，向玻璃体腔注射曲安奈德染色残余玻璃体，将其中一个上通道套管从光探头上方拔出，将另一个套管连同插入的塞子一起拔出。采用眼前节光学相干断层扫描（AS-OCT）对上方巩膜切口的术后结膜泡进行盲法评估；不可检测到的结膜泡被归类为 0 级（B0），薄的结膜泡（≤半巩膜厚度）为 1 级（B1），厚的结膜泡（>半巩膜厚度）为 2 级（B2）。通过裂隙灯照片对术后切口处玻璃体嵌顿进行盲法评估；无嵌顿为 0 级（V0），薄的嵌顿为 1 级（V1），厚的嵌顿为 2 级（V2）。
13.7%的巩膜切口处发现结膜泡（11.3%结膜泡 B1，2.4%结膜泡 B2）。无结膜泡（B0）的巩膜切口处发现玻璃体嵌顿 96.5%，结膜泡 B1 的切口处发现玻璃体嵌顿 81.8%，结膜泡 B2 的切口处发现玻璃体嵌顿 14.3%。玻璃体嵌顿与无结膜泡显著相关（P<0.001）。
在我们的实验模型中，玻璃体嵌顿于巩膜切口处与切口漏液减少相关。减少玻璃体嵌顿的操作，如在套管拔出过程中插入非空心探头，可能会降低巩膜切口的闭合能力。
