Keratometric alterations following the 25‐gauge transconjunctival sutureless pars plana vitrectomy versus the conventional pars plana vitrectomy

Analysis of Changes in Corneal Topography after 27-Gauge Transconjunctival Microincision Vitrectomy Combined with Cataract Surgery

Purpose

To investigate changes in the corneal shape before and after vitrectomy, over a period of time, using a 27-gauge system.

Methods

Forty-five eyes underwent a combination of cataract surgery and vitrectomy. The surgeries were performed using a 27-gauge transconjunctival vitrectomy system, in which the corneal topography could be performed up to three months after the surgery. The surgeries were performed for an epiretinal membrane in 11 eyes, a macular hole in 14 eyes, and rhegmatogenous retinal detachment in 20 eyes. All of the surgeries were performed by the same surgeon, and in all cases, a 4-port 27-gauge vitrectomy device was used. Cataract surgery in all patients was performed with a 2.4 mm corneoscleral incision at 11 o'clock. The surgeries were performed without suturing the operative wound in all cases. Corneal topography was performed using a TMS-4 topographer (Tomey Corporation, Tokyo, Japan). The examinations were performed the day before and 1 day, 1 week, 1 month, and 3 months after the surgery. The results of corneal topography for the spherical, regular astigmatic, asymmetric, and high-order irregular astigmatic components were compared before and after surgery.

Results

No significant differences were seen in any of the components in the epiretinal membrane group, but significant differences were seen in the asymmetric components and the high-order irregular astigmatic components between the macular hole and rhegmatogenous retinal detachment groups (p < 0.05). There were no significant changes in intraocular pressure on any measurement time in the postoperative period compared to preoperative intraocular pressure.

Conclusion

Irregular astigmatism was seen after surgery when 27-gauge vitrectomy with a 4-port system was performed together with cataract surgery with a 2.4 mm incision.

Changes in the anterior segment of the eye following uncomplicated pars plana vitrectomy. A review

Pars plana vitrectomy is currently the most common technique used in retinal surgery. Although primarily involving the posterior segment of the eye it also affects the anterior segment. As this is a less published topic, the aim of this paper was to review the literature on changes in the anterior segment after uncomplicated pars plana vitrectomy using data based literature search. The conclusions are that even in otherwise ophthalmologically healthy patients, complications may occur in the anterior segment. Surgeons need to pay utmost attention in glaucoma patients and in those with endothelial insufficiency who are at highest risk of complications. He/she must also correctly plan a potential cataract surgery if not already done earlier. From the literature, most of the changes in the anterior segment after uncomplicated PPV are found to be temporary.

Refractive shift of silicone oil tamponade in pseudophakic eye

Background

Refraction change of silicone oil (SO) tamponade in phakic and aphakic eye has been studied thoroughly; however, it is rarely studied in pseudophakic eye. In this paper we aimed to deduce a theoretical formula predicting refractive shift of silicone oil tamponade in pseudophakic eye and compared it with clinical findings.

Method

A theoretical formula was deduced through strict geometric optical principles under the Helmholtz Schematic eye model. Pre/postoperative refractive status of patients who previously underwent phacoemulsification, intraocular lens (IOL) implant, vitrectomy, SO tamponade and required SO extraction was studied.

Results

Twenty-six patients (27 eyes, 13 males and 13 females) were studied. Refractive error of SO-off was -1.88 ± 2.73D, and of SO-in was 2.02 ± 3.90. Refractive shift of SO tamponade was -3.90 ± 1.74D. Refractive shift was significantly associated with refractive power of IOL (r = -0.7903, p < 0.0001, Pearson correlation test) and anterior chamber distance (ACD, r = 0.3840, p = 0.0480, Pearson correlation test). Theoretical refractive shift was -4.10 ± 1.51D, and there was no significant difference between the theoretical and the clinical refractive shift (p = 0.3329, Paired T test).

Conclusions

Refractive shift of SO tamponade in pseudophakic eye correlates with refractive power of implanted IOL and ACD, and strong correlation between theoretical formula and clinical findings was detected.

Electronic supplementary material

The online version of this article (doi:10.1186/s12886-016-0243-z) contains supplementary material, which is available to authorized users.

Comparison of Conjunctival Cytological Alterations following Conventional and Sutureless Sclerotomies

PURPOSE

To assess the alterations in conjunctival impression cytology following 23-gauge transconjunctival sutureless versus conventional pars plana vitrectomy.

PATIENTS AND METHODS

Sixty consecutive patients were enrolled in the study. Conjunctival impression cytology was performed on 30 eyes (of 30 subjects) with 23-gauge transconjunctival sutureless vitrectomy and on 30 eyes (of 30 subjects) with conventional vitrectomy. Conjunctival impression cytology was performed preoperatively on the 1st day and in the 3rd month after the surgery. Impression cytology specimens of each group were graded and scored using a range of 0-3 according to Nelson's method.

RESULTS

In the conventional pars plana vitrectomy group, statistically significant alterations in the conjunctival impression cytology were detected on the 1st postoperative day (p = 0.001) and in the 3rd postoperative month (p = 0.001), whereas in the 23-gauge transconjunctival sutureless pars plana vitrectomy group, statistically significant changes were observed on the 1st postoperative day. However, no significant changes were observed in the following 3 postoperative months (p = 0.08).

CONCLUSION

The properties of impression cytology were altered in the early postoperative period after sutureless and conventional vitrectomy. These changes were improved in the sutureless vitrectomy group only. Sutureless vitrectomy also had an advantageous effect on the conjunctival cytological changes and conjunctival structure.

Study of intraocular pressure after 23-gauge and 25-gauge pars plana vitrectomy randomized to fluid versus air fill

PURPOSE

To determine if a difference in intraocular pressure (IOP) exists after small-gauge pars plana vitrectomy randomized to fluid versus 80% sterile air fill.

METHODS

Ninety-two eyes undergoing 23-gauge and 25-gauge transconjunctival pars plana vitrectomy were randomized to fluid versus air fill, and IOP was measured at 5 different time points.

RESULTS

There is no difference in the mean IOP for eyes undergoing small-gauge pars plana vitrectomy randomized to fluid versus air fill after vitrectomy. Using 23-gauge instrumentation, the mean immediate and 2-hour postoperative IOPs were statistically lower than the mean preoperative IOP. The mean Postoperative Day 1 and Week 1 IOPs were statistically higher than the mean immediate postoperative IOP. Using 25-gauge instrumentation, the mean IOP was not statistically different at any time points in the 2 groups. When comparing 23-gauge with 25-gauge instrumentation, the immediate postoperative IOP was statistically lower and the rate of suture closure for sclerotomies was higher for 23-gauge vitrectomy.

CONCLUSION

When performing 23-gauge or 25-gauge pars plana vitrectomy, there was no difference in mean IOP for fluid- versus air-filled eyes. However, the mean IOP in the immediate postoperative period was statistically lower, and there was a higher rate of suture closure for 23-gauge compared with 25-gauge instrumentation.