Toklu Enes, Altinisik Muhammed, Elbay Ahmet, Koytak Arif
Departmentof Ophthalmology, Kemalpasa State Hospital, İzmir 35730, Turkey.
Department of Ophthalmology, Faculty of Medicine, Manisa Celal Bayar University, Manisa 45040, Turkey.
Int J Ophthalmol. 2020 Nov 18;13(11):1745-1752. doi: 10.18240/ijo.2020.11.10. eCollection 2020.
To compare changes in anterior segment topography and axial length (AL) evaluated with Pentacam and IOL Master after pars plana vitrectomy (PPV) performed with and without vitreous base shaving.
This prospective study included patients who underwent PPV or phacoemulsification+PPV (Phaco+PPV) for various indications. Patients who underwent total posterior hyaloid detachment and excessive vitreous base shaving with scleral indentation were referred to as complete PPV (c-PPV). The patients whom posterior hyaloid was separated as far as the posterior arcades and vitreous base shaving with scleral depression was not performed were classified as the partial PPV (p-PPV) group. All patients underwent detailed ophthalmologic examinations preoperatively and 1wk, 1, and 3mo postoperatively. Changes in the anterior chamber depth (ACD), anterior chamber volume (ACV), iridocorneal angle (ICA), central corneal thickness (CCT), and keratometric measurements (K and K) were evaluated with Pentacam HR. Changes in the AL measurements were analyzed with IOL Master.
A significant increase in ACD was observed in c-PPV cases (=0.02), but this increase was not significant in the p-PPV group (=0.053). In contrast, ICA increased significantly in the c-PPV group (=0.02) but decreased in the p-PPV group (=0.09). BCVA was significantly improved in the c-PPV group from week 1 (<0.001) while the increase in the p-PPV group reached significance at 3mo (=0.035). CCT increased in the first week and later returned to baseline in both groups. No significant differences in the other parameters were observed between the groups, and there were no significant changes in intraocular pressure, ACV, AL, K or K values (>0.05 for all).
Incomplete posterior hyaloid excision and not removing the vitreous base in PPV surgeries may create a more stable anterior chamber, thus preventing the downward movement of the lens-iris diaphragm, and may cause ciliary body retraction, thereby reducing ICA. Awareness of these effects can provide some amount of guidance to physicians in selecting the appropriate PPV procedure and preempting surgical complications.
比较在有或没有玻璃体基底部切除的扁平部玻璃体切除术（PPV）后，使用Pentacam和IOL Master评估的眼前节形态和眼轴长度（AL）的变化。
这项前瞻性研究纳入了因各种适应症接受PPV或超声乳化+PPV（Phaco+PPV）的患者。接受完全后玻璃体脱离和巩膜压陷下过度玻璃体基底部切除的患者被称为完全PPV（c-PPV）。后玻璃体分离至后弓状静脉且未进行巩膜压迫下玻璃体基底部切除的患者被分类为部分PPV（p-PPV）组。所有患者在术前以及术后1周、1个月和3个月接受详细的眼科检查。使用Pentacam HR评估前房深度（ACD）、前房容积（ACV）、虹膜角膜角（ICA）、中央角膜厚度（CCT）和角膜曲率测量值（K和K）的变化。使用IOL Master分析AL测量值的变化。
在c-PPV病例中观察到ACD显著增加（=0.02），但在p-PPV组中这种增加不显著（=0.053）。相反，c-PPV组的ICA显著增加（=0.02），而p-PPV组则下降（=0.09）。c-PPV组的最佳矫正视力（BCVA）从第1周起显著改善（<0.001），而p-PPV组在3个月时增加达到显著水平（=0.035）。两组的CCT在第1周均增加，随后恢复至基线水平。两组之间在其他参数上未观察到显著差异，眼压、ACV、AL、K或K值也均无显著变化（所有均>0.05）。
PPV手术中后玻璃体切除不完全且未切除玻璃体基底部可能会使前房更稳定，从而防止晶状体-虹膜隔向下移动，并可能导致睫状体后缩，进而减小ICA。了解这些影响可为医生选择合适的PPV手术及预防手术并发症提供一定指导。
