Use of 25% sulfur hexafluoride gas mixture may minimize short-term postoperative hypotony in sutureless 25-gauge pars plana vitrectomy surgery

Expansile gas concentration in primary pseudophakic retinal detachment repair, effect on intraocular pressure and outcomes; the Manchester Pseudophakic Retinal Detachment Study

PURPOSE

To investigate the effect of isovolumetric and expansile gas tamponade concentrations on single surgery anatomical success (SSAS) and day 1 intraocular pressure (IOPD1) following pars plana vitrectomy (PPV) for mild-moderate complexity primary pseudophakic rhegmatogenous retinal detachment (PRD).

METHODS

We conducted a single-centre retrospective continuous and comparative study on eyes that had undergone small-gauge PPV using isovolumetric versus expansile gas for PRD repair between 2011 and 2020 at a single tertiary vitreoretinal centre in UK. We performed propensity score matching (PSM) using preoperative findings as covariates to account for relevant confounders. Significant risk factors such as proliferative vitreoretinopathy C or giant retinal tears were excluded.

RESULTS

From 456 eyes, PSM analysis matched 240 eyes with 120 in each group. The median (interquartile range) follow-up was 96 (59 to 218) days. The SSAS was 229/240 (95.8%) overall; 115/120 (95.8%) and 114/120 (95.0%) in isovolumetric and expansile groups, respectively (p = 1.000). Relative to the isovolumetric group, the expansile group had lower proportion of eyes with IOP ≤ 21 mmHg (odds ratio, 95% confidence interval, 0.40 [0.23-0.68], p < 0.001); but significantly higher number of eyes with IOP ≥ 22 mmHg (2.53 [1.48-4.34], p < 0.001), ≥ 25 mmHg (2.77 [1.43-5.33], p < 0.001), ≥ 30 mmHg (2.90 [1.28-6.58], p = 0.006) and ≥ 40 mmHg (p = 0.029, isovolumetric: 0 [0%] vs expansile group: 6 [5%]). There was only one case of hypotony (≤ 5 mmHg) 1/240 (0.4%) which occurred in the expansile group.

CONCLUSIONS

Expansile gas concentration does not impact SSAS but is associated with significantly raised IOPD1 with no reduction in hypotony rates following PPV for primary PRD.

Examining the Necessity of Postoperative Day-1 Review After Pars Plana Vitrectomy: A Meta-Analysis

BACKGROUND AND OBJECTIVES

This study aimed to evaluate the necessity of the postoperative day-1 (POD1) review after pars plana vitrectomy.

PATIENTS AND METHODS

The analysis included available literature that documented medical and surgical interventions performed on POD1 review after pars plana vitrectomy. A meta-analysis of proportions was conducted using a binomial-normal model to analyze three data sets consisting of all interventions, medical interventions, and surgical interventions. Heterogeneity and publication bias analyses were performed.

RESULTS

POD1 reviews of 2,262 patients across 14 studies were examined to yield a total POD1 intervention rate estimate of 4.7% (95% confidence interval [CI], 3.0-13.9). When stratified by medical or surgical intervention, the intervention rate estimates were 4.1% (95% CI, 1.4-11.6) and 0.7% (95% CI, 0.3-1.3), respectively. The most common complication requiring postoperative intervention was elevated intraocular pressure.

CONCLUSION

Given the wide confidence intervals of the estimated intervention rates, variability in postoperative practices, and range of interventions performed, the POD1 review cannot be discarded in its entirety. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:513-518.].

Treatment-Emergent Adverse Events in Gene Therapy Trials for Inherited Retinal Diseases: A Narrative Review

Patient safety is a primary priority in the conduction of retinal gene therapy trials. An understanding of risk factors and mitigation strategies for post-procedure complications is crucial for the optimization of gene therapy clinical trial protocols. In this review, we synthesize the literature on ocular delivery methods, vector platforms, and treatment-emergent adverse effects in recent gene therapy clinical trials for inherited retinal diseases.

Vitrectomy without prone positioning for rhegmatogenous retinal detachments in eyes with inferior retinal breaks

Purpose

To compare the anatomic and functional outcomes of pars plana vitrectomy (PPV) for treating rhegmatogenous retinal detachments (RRDs) between two groups with and without postoperative prone positioning.

Methods

This retrospective cohort study included 142 eyes of 142 patients with a primary RRD. All patients underwent PPV with 20% sulfur hexafluoride gas tamponade and were divided into two groups: the groups that did and did not maintain a prone position postoperatively. All patients were followed for more than 3 months. The main outcome measures were the best-corrected visual acuity (BCVA), retinal reattachment rate, and postoperative complications.

Results

Sixty-five eyes were included in the prone position group and 77 eyes in the group without prone positioning; the respective initial reattachment rates were 83.1% and 96.1%, a difference that reach significance (p = 0.011). In the eyes with inferior breaks, the initial reattachment rate was 94.7% (18 eyes) without prone positioning, which was significantly (p = 0.036) better than the 60% (6 eyes) initial reattachment rate in the group with prone positioning. In the eyes without inferior breaks, there was no significant difference in the initial reattachment rates between the two groups. The BCVAs at the 3-month postoperative visit did not differ significantly between the two groups. An epiretinal membrane (ERM) was observed postoperatively in 10 (13.0%) eyes in the group without prone positioning; no ERMs were seen postoperatively in eyes in which the internal limiting membrane (ILM) was peeled during PPV.

Conclusions

PPV without postoperative prone positioning is associated with a higher reattachment rate in eyes with a RRD, especially those with inferior retinal breaks. PPV with postoperative supine and lateral positioning might be beneficial to manage RRDs associated with inferior retinal breaks if ILM peeling is performed intraoperatively.

Comparison of 25-gauge sutureless vitrectomy and 20-gauge vitrectomy in the treatment of posterior capsule opacification in pseudophakic children

AIM

To compare the effectiveness and safety of pars plana capsulotomy and vitrectomy using 25-gauge tansconjunctival sutureless vitrectomy system and 20-gauge vitrectomy system for posterior capsule opacification (PCO) in pseudophakic children.

METHODS

Retrospectively study. Pars plana capsulotomy and vitrectomy using 25-gauge sutureless vitrectomy system was performed for PCO in the study group (32 eyes). Patients in the control group (34 eyes) underwent capsulotomy and vitrectomy using standard 20-gauge vitrectomy system, providing a comparison between 2 groups with regard to preoperative and postoperative best corrected visual acuity (BCVA), intraocular pressure (IOP), and intraoperative and postoperative complications. The two groups were performed consequentially. The patients ages ranged from 2 to 13y (means: 6.61±2.73y). Surgical technique, intraoperative and postoperative complications, visual acuity, IOP, and recurrent PCO were recorded.

RESULTS

The surgical procedure was performed uneventfully in all patients. Visual acuity improved significantly in both groups. BCVA improved in 22 eyes (81.5%) in the study group and in 28 eyes (87.5%) in the control group. There was no statistical difference of visual acuity that were attainable in two groups (H=0.115, P=0.909). Mean postoperative IOP showed no significant difference between the groups at 1wk. All sort of PCO were accomplished by 20-gauge system, while 25-gauge system was effective for pearls style and 2 grade of fibrous PCO, and was insufficient to grade 3 of PCO. In the study group two cases were not accomplished by 25-gauge system while 20-gauge system conquered them. Compared with the control group, mean operative time for opening and closing the sclerotomy in the study group was considerably reduced. The mean follow-up was 38.2mo (range: 8-79mo). During the follow-up period, no incision leakage, corneal edema, vitreous loss, IOL damage, retinal detachment, recurrent PCO, or other complications were noted.

CONCLUSION

Pars plana capsulotomy and vitrectomy using 25-gauge transconjunctival sutureless vitrectomy appeared to be a safe and effective approach for PCO in pseudophakic children. Combined sutureless surgery needed shorter setup time for sclerotomy and caused less surgical trauma than combined surgery with 20-gauge vitrectomy. Therefore, this type of procedure would be a good option for selected cases with PCO in pseudophakic children.