DIFFERENT SURGICAL MODALITIES FOR MANAGEMENT OF PERSISTENT GLAUCOMA AFTER SILICONE OIL REMOVAL IN VITRECTOMIZED EYES: One Year Comparative Study

Risk Factors and Management of Intraocular Pressure Elevation After Vitrectomy Combined with Silicone Oil Tamponade

Silicone oil has emerged as the common option for intraocular tamponade during complicated retina vitrectomy. However, the postoperative elevation of intraocular pressure (IOP), influenced by numerous factors, remains a significant and frequently encountered complication that poses a potential threat to vision. Extensive research has been conducted to investigate the risk factors associated with elevated IOP following silicone oil tamponade, including silicone oil viscosity, preoperative high IOP, diabetes, and lens status. This comprehensive review aims to gather and summarize the current research findings regarding the risk factors contributing to IOP elevation following silicone oil tamponade, as well as the optimal management strategies for secondary glaucoma. The analysis includes the physicochemical properties of silicone oil, preoperative and intraoperative risk factors, and the effective management of secondary glaucoma. Enhancing our understanding of the primary factors associated with silicone oil-induced IOP elevation will facilitate the guidance of timely and appropriate interventions.

Surgical Treatment in Silicone Oil-Associated Glaucoma

Glaucoma is a vision threatening, not uncommon complication of eyes that have undergone pars plana vitrectomy with silicone oil endotamponade. Although most patients respond well to medical antiglaucoma therapy, there are refractory cases where surgery is required to control the intraocular pressure. This review, following a comprehensive literature search in the Medline database, aims to present the most important surgical techniques currently in use for glaucoma associated with silicone oil endotamponade and their indication depending on the mechanism of glaucoma. In cases of pupillary block, the presence of a patent iridotomy or iridectomy must be ensured, either by laser or surgically. When silicone oil is in excess and whenever the retinal status permits it, partial or complete removal of the silicone oil should be performed. Trabeculectomy has shown higher failure rates and more complications in these cases compared to other indications, so alternate methods are warranted. For very high intraocular pressures, glaucoma drainage devices and transscleral cyclophotocoagulation are the most used options, with good efficacy and safety profiles, although rarely they may have serious complications. The Ex-PRESS mini shunt has shown excellent results and lower rates of complications. For less important IOP elevations, minimally invasive glaucoma surgery and selective laser trabeculoplasty may be used, either alone or in conjunction with other methods.

Outcomes of Gonioscopy-assisted Transluminal Trabeculotomy in Vitrectomized Patients With Secondary Glaucoma After Silicone Oil Removal

PRCIS

The present study demonstrates that surgical success rates of gonioscopy-assisted transluminal trabeculotomy (GATT) with a target intraocular pressure (IOP)≤21 mm Hg are 93.3% (for qualified success) and 26.7% (for complete success) in vitrectomized patients exhibiting secondary open-angle glaucoma (SOAG) after silicone oil (SO) removal, for an average follow-up of 37.5 months.

PURPOSE

To report the long-term outcomes of GATT in vitrectomized patients exhibiting SOAG after SO removal.

SETTING

Retrospective case-series study.

PATIENT POPULATION

This retrospective case-series study enrolled vitrectomized patients who underwent uneventful GATT surgery between May 2014 and May 2019 at Gazi University Hospital for the treatment of medically uncontrolled SOAG after SO removal.

MAIN OUTCOME MEASURES

At baseline and at each postoperative visit, a detailed ophthalmic examination consisting of slit-lamp biomicroscopy, indirect ophthalmoscopy, macular optical coherence tomography, and Goldmann applanation tonometry was performed in all patients. Baseline demographic and clinical characteristics, duration between pars plana vitrectomy and SO removal, duration between SO removal and onset of SOAG, follow-up time, need for antiglaucoma medication, visual acuity, and IOP measurements were noted. Surgical success was defined as an IOP≤21 and ≥6 mm Hg with (qualified success) and without (complete success) IOP-lowering medication.

RESULTS

A total of 15 patients had a history of pars plana vitrectomy with 1000 centistoke SO tamponade before the GATT surgery. GATT was performed in all patients with SOAG after SO removal. The mean age and follow-up of the patients were 53.6±11.8 years (range, 34 to 72 y) and 37.5±15.1 months (range, 12 to 61 mo), respectively. The average duration of SO tamponade in the vitreous cavity was 7.5±1.6 months (range, 5 to 10 mo). The average duration between the SO removal and the development of SOAG was 14.1±13.2 months (range, 2 to 46 mo). The mean IOP decreased from 31.0±4.1 mm Hg at baseline to 15.6±4.6 mm Hg at final visit. The mean final logMAR BCVA was 0.92±0.58 (range, 2 to 0.045). Qualified surgical success was achieved in 14 (93.3%) patients, whereas complete success was achieved in only 4 (26.7%) patients (P<0.001).

CONCLUSIONS

GATT seems to be safe and successful procedure for controlling IOP in patients exhibiting SOAG after SO removal. However, most patients may require antiglaucoma medication during the follow-up, particularly within the first 2 postoperative years.

Combined Trabeculotomy-Trabeculectomy Versus Trabeculectomy for Treatment of Silicone Oil-induced Ocular Hypertension

PRCIS

Combined trabeculotomy-trabeculectomy (CTT) has a significantly better hypotensive effect than trabeculectomy and a higher success rate in cases of silicone oil-induced ocular hypertension.

PURPOSE

To compare the ocular hypotensive effect of CTT with mitomycin-C (MMC) to that of trabeculectomy with MMC in cases of silicone oil-induced ocular hypertension.

PATIENTS AND METHODS

Thirty eyes of 30 patients with high intraocular pressure (IOP) after vitrectomy and silicone oil injection (followed by silicone oil removal) were randomly allocated to 2 groups in this randomized trial. Group A was composed of 15 cases who underwent combined CTT with MMC while group B cases contained 15 cases undergoing trabeculectomy with MMC. Patients were followed up for 12 months. We included patients above 18 years old, having performed vitrectomy and silicone oil injection followed by oil removal, and having IOP >21 mm Hg uncontrollable by antiglaucoma medications.

RESULTS

The postoperative IOP drop was significantly greater in group A than in group B at all follow up visits (P<0.05). Compared with preoperative IOP, both surgeries produced a significantly lower postoperative IOP at all follow-up visits (P<0.05). For group A, complete success rates (IOP≤21 mm Hg without ocular hypotensive medications) and qualified success rates (IOP≤21 mm Hg with or without ocular hypotensive medications) were both higher than for group B.

CONCLUSION

Both surgeries effectively reduce IOP in cases of silicone oil-induced ocular hypertension, but CTT has a significantly better hypotensive effect and a higher success rate on the long-term.

Slow Coagulation Transscleral Cyclophotocoagulation for Postvitrectomy Patients With Silicone Oil-induced Glaucoma

PRECIS

Slow coagulation transscleral cyclophotocoagulation (TSCPC) is an effective and safe glaucoma surgery in patients with medically uncontrolled silicone oil (SO)-induced glaucoma.

PURPOSE

The purpose of this study was to report the outcomes of slow coagulation continuous wave TSCPC in patients with medically uncontrolled secondary glaucoma following pars plana vitrectomy (PPV) and intravitreal SO injection.

PATIENTS AND METHODS

This retrospective study enrolled patients with medically uncontrolled glaucoma secondary to PPV with SO injection who underwent TSCPC using slow coagulation TSCPC settings (power of 1250 mW and duration of 4 s). The primary outcome measure was surgical success at 12 months. Surgical success was defined as an intraocular pressure 6 to 21 mm Hg and reduced ≥20% from baseline, no reoperation for glaucoma, and no loss of light perception vision. Secondary outcome measures included number of glaucoma medications, visual acuity changes, and surgical complications.

RESULTS

A total of 18 eyes of 18 patients were included in the study. The mean age and follow-up of the patients were 51.94±14.5 years and 16.3±3.5 months, respectively. The mean intraocular pressure decreased from 29.7±9.6 mm Hg preoperatively to 14.6±6.5 mm Hg at 12 months postoperatively (P<0.001). Glaucoma medications were reduced from 4.2±0.9 at baseline to 1.9±1.3 at 12 months after TSCPC (P<0.001). A nonsignificant change of logarithm of the minimum angle of resolution visual acuity was observed at 12 months (P=0.722). The success rate at 12 months was 72.2%. No major complications were reported during the first year of follow-up.

CONCLUSION

Slow coagulation TSCPC had high efficacy and minimal complications when used as an initial glaucoma surgical procedure in patients with SO-induced glaucoma.

Outcome of Surgical Management of Glaucoma Following Complex Retinal Detachment Repair With Silicone Oil Tamponade: Drainage Implant Versus Cyclophotocoagulation

PRéCIS:: Glaucoma drainage devices (GDDs) are effective for the management of silicone oil-induced glaucoma. Although cyclophotocoagulation (CPC) has the advantage of shorter operative time and repeatability, it carries a higher risk of failure, blindness, and phthisis.

BACKGROUND/AIMS

To compare the surgical outcome of GDD implantation and diode laser CPC in the management of refractory glaucoma following vitrectomy with silicone oil (SO) injection.

MATERIALS AND METHODS

In total, 56 eyes with refractory glaucoma after SO tamponade that underwent either CPC or GDD implantation were retrospectively evaluated. All patients underwent a complete ophthalmic examination and intraocular pressure (IOP) measurement at baseline and 1 day, 1 week, 1, 3, 6, and 12 months postoperatively. The rates of complete success and qualified success (for IOP between ≥5 and ≤21 mm Hg) were analyzed.

RESULTS

A total of 17 eyes underwent GDD implantation and 39 eyes underwent CPC. The preoperative IOP was 35.7±7.9 mm Hg and 27.8±8.4 mm Hg for the CPC and GDD groups, respectively (P=0.001), with a worse baseline visual acuity (P=0.01) and a higher proportion of SO-filled eyes in the CPC group (P<0.01). The IOP at 1 year postoperatively was 23.5±11.5 mm Hg and 15.3±5.9 mm Hg for the CPC and GDD group, respectively (P=0.01). Both groups achieved a reduction in IOP and number of medications at 1 year (P<0.001). The success rate in the GDD group was 94.1% (16/17), and 53.8% (21/39) in the CPC group at 12 months (P<0.005). Five eyes and 1 eye lost light perception vision in the CPC and GDD groups, respectively.

CONCLUSIONS

GDD implantation may carry a higher surgical success rate than CPC. However, CPC retains the advantage of being technically easier and repeatable.

Intraocular Pressure Rise Linked to Silicone Oil in Retinal Surgery: A Review

Silicone oil represents the main choice for intraocular tamponade in cases of complicated retinal detachment surgery. The intraocular pressure of an eye filled with silicone oil could increase, driven by a variety of different forces, according to several mechanisms. Two main conditions have been highlighted, depending on the onset: early hypertension or late glaucoma. The different types of silicone oils and their physico-chemical properties are varied and may play a role in the determination of intraocular pressure rise. The current body of literature allows for the illustration and categorization of the incidence and risk factors, as well as the pathogenesis and the management of the early postoperative hypertension subtended by an open- and closed-angle, along with the late onset silicone oil-induced glaucoma. Understanding the leading actors on the stage of ocular pressure elevation concurrently with silicone oil application for retinal surgery could help in guiding the timely and appropriate course of treatment.

Pars plana Ex-Press mini shunt for management of persistent glaucoma in vitrectomized eyes: A novel technique

PURPOSE

To evaluate the safety and efficacy of a novel approach to implant Ex-Press mini shunt via the pars plana under a scleral flap in pseudophakic or aphakic, vitrectomized patients with secondary refractory glaucoma.

METHODS

A prospective interventional case series of three patients with secondary glaucoma after pars plana vitrectomy. Intraocular pressure was not controlled by silicone oil removal, if the patient was siliconized, nor the maximum medical treatment. Ex-Press mini shunt via the pars plana was implanted. We evaluated the control of intraocular pressure and the development of intraoperative and postoperative complications.

RESULTS

During 1-year follow-up, control of intraocular pressure was achieved; 14, 15, and 15 mmHg at the 3 months, and 15, 15, and 16 mmHg at the 6 months in our three cases without antiglaucoma treatment and 16, 16, and 18 with single antiglaucoma medication at 1 year. Blebs were posterior and diffuse. No complications were encountered intraoperatively or postoperatively. Ultrasound biomicroscopy showed suprachoroidal posterior lake of fluid as an additional filtration route without any choroidal or retinal complication.

CONCLUSION

Implantation of Ex-Press mini shunt via the pars plana in aphakic or pseudophakic, vitrectomized eyes is a promising, safe, and effective technique in patients with secondary glaucoma.

Trabeculectomy and EX-PRESS Implantation in Open-Angle Glaucoma: An Updated Meta-Analysis of Randomized Controlled Trials

Purpose

Accumulating studies comparing the efficacy and safety of trabeculectomy and EX-PRESS implantation in open-angle glaucoma (OAG) report inconsistent findings. Thus, we conducted the updated meta-analysis to clarify the issue.

Methods

Randomized controlled trials (RCTs) were selected through search of databases PubMed, Web of Science, Embase, and the Cochrane Library from their inception up until November 2018. The pooled mean difference (MD) for intraocular pressure reduction (IOPR) and antiglaucoma medication reduction, odds ratio (OR) for operative success, complication, and postoperative intervention was calculated using the random effects model.

Results

8 RCTs were enrolled, including 223 eyes in the EX-PRESS group and 217 eyes in the trabeculectomy group. EX-PRESS device implantation had a better IOPR% at 12 months postoperatively (MD = 8.9, 95% confidence interval (CI) = 2.5-15.3, P=0.006). There was no statistically significant difference in the antiglaucoma medication reduction (MD = 6.01, 95% CI = -4.13-16.15, P=0.25) and qualified success (P > 0.05). Statistically higher complete success at 1 year postoperatively was found in the EX-PRESS group (OR = 3.26, 95% CI = 1.24-8.55, P=0.02). EX-PRESS was associated with a lower frequency of increased IOP (OR = 0.15, 95% CI = 0.03-0.93, P=0.04) and hyphema (OR = 0.20, 95% CI = 0.05-0.74, P=0.02). Less postoperative intervention was needed in the EX-PRESS group (OR = 0.43, 95% CI = 0.20-0.94, P=0.04).

Conclusion

For OAG patients, EX-PRESS implantation provided better efficacy in IOP control and complete success at 1 year postoperatively, with fewer increased IOP and hyphema as well as postoperative interventions. EX-PRESS device and trabeculectomy were similar in the qualified success and antiglaucoma medication reduction.

Reporting Harm in Glaucoma Surgical Trials: Systematic Review and a Consensus-Derived New Classification System

PURPOSE

To evaluate the standards of harm reporting for glaucoma surgical trials and to develop a classification system for reporting surgical complication severity.

DESIGN

Systematic review and Delphi consensus method.

METHODS

Systematic review of glaucoma surgical trials published from January 2010 until July 2017 with a quality assessment against the CONSORT checklist for harm. A Delphi method was employed to generate consensus grading (interquartile range ≤ 2) among international glaucoma experts (n = 43) on severity of glaucoma surgical complications, and specifically for trabeculectomy and aqueous shunt complications, from 1 (no clinical significance) to 10 (most severe complication).

RESULTS

Forty-seven studies were eligible. The items of the CONSORT checklist for harm that were most frequently missing were use of a validated instrument to report severity (0%), withdrawals due to harm, and subgroup analyses, both reported in 3 publications (6.4%). Most glaucoma experts participating in the Delphi process (80%) completed the second round, and consensus was achieved for all but 1 complication. The least severe complications (graded 2) were "transient loss of vision," "early low intraocular pressure," "choroidal detachment anterior to equator," "small layered hyphema < 1 mm," and "increased lens opacity not clinically significant." The most severe complications (graded 10) were "endophthalmitis" and "permanent severe loss of vision (hand movements or worse)."

CONCLUSIONS

Glaucoma surgical randomized controlled trials report frequency of complications, but their severity is rarely reported. The quality of harm reporting is poor. We propose the use of a newly developed system of classification for assessing the severity of surgical complications based on consensus.