Incidence and management of elevated intraocular pressure after silicone oil injection

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.

Prediction model for elevated intraocular pressure risk after silicone oil filling based on clinical features

Background

To evaluate risk factors and further develop prediction models for intraocular pressure elevation (IOP) after vitreoretinal surgery with silicone oil tamponade to support clinical management.

Methods

A retrospective study analyzed 1,061 eyes of 1,061 consecutive patients that presented to the Jiangsu Province Hospital between December 2015 and December 2020, the IOP was measured from the preoperative visit and at the 1-week, 1-month, 3-month, and 6-month visits, and the final postoperative visit before silicone oil removal. Four machine learning methods were used to carried out the prediction of IOP elevation: Decision Tree, Logistic Regression, Random Forest, and Gradient-Boosted Decision Trees (GBDT) based on features including demographic and clinical characteristics, preoperative factors and surgical factors. Predictors were selected based on the p-value of the univariate analysis.

Results

Elevated intraocular pressure developed in 26.01% of the eyes postoperatively. Elevated intraocular pressure primarily occurred within 1-2 weeks after surgery. Additionally, the majority of IOP values were distributed around 25-40 mmHg. GBDT utilizing features with p-values less than 0.5 from the hypothesis testing demonstrated the best predictive performance for 0.7944 in accuracy. The analysis revealed that age, sex, hypertension, diabetes, myopia, retinal detachment, lens status and biological parameters have predictive value.

Conclusion

Age, sex, hypertension, diabetes, myopia, retinal detachment, lens status and biological parameters have influence on postoperative intraocular pressure elevation for patients with silicone oil tamponade after pars plana vitrectomy. The prediction model showed promising accuracy for the occurrence of IOP elevation. This may have some reference significance for reducing the incidence of high intraocular pressure after pars plana vitrectomy combined with silicone oil filling.

Inferior implant of XEN63 Gel stent in a refractory open-angle glaucoma due to silicone oil tamponade: A case report

BACKGROUND

To discuss the efficacy of an inferior implant of XEN 63 gel stent in a patient with refractory glaucoma after trabeculectomy failure and vitreoretinal surgery with silicone oil tamponade.

CASE DESCRIPTION

We report the case of a 73-year-old man with a history of refractory open glaucoma with trabeculectomy failure. He experienced recurrent retinal detachments with silicone oil tamponade, with uncontrolled intra-ocular pressure (IOP) after silicone oil removal. Due to the presence of oil emulsion in the anterior chamber, the chosen location for XEN 63 implantation was the infero-temporal quadrant. Mild hyphema and vitreous hemorrhage were seen post-operatively, but were self-limiting. At week 1, the intraocular pressure was 8 mmHg with a well-formed bleb seen in anterior segment optical coherence tomography (AS-OCT). At 6 month follow up, the patient maintained a IOP of 12 mmHg without topical hypotensive drugs. Slit lamp examination revealed a widespread, developed bleb with no signs of inflammation.

CONCLUSION

In this case of refractory glaucoma in a vitrectomized eye with previous oil tamponade, the inferior placement of the XEN 63 gel stent delivered an adequate intraocular pressure even at 6-months follow up, with a diffuse functional infero-nasal bleb seen with AS-OCT.

Functional and structural outcomes and complications after pars plana vitrectomy for severe features of proliferative diabetic retinopathy in type 1 and type 2 diabetes mellitus

PURPOSE

To evaluate the functional and structural outcomes as well as postoperative complications after pars plana vitrectomy (PPV) for severe features of proliferative diabetic retinopathy (PDR) in type 1 and type 2 diabetes mellitus (DM) patients.

METHODS

Twenty two eyes of type 1 diabetics (DM1 group) and 27 eyes of type 2 diabetics (DM2 group) were included. Best corrected visual acuity (BCVA), intraocular pressure (IOP), postoperative structural changes in optical coherence tomography (OCT) and postoperative complications such as recurrent vitreous haemorrhage, diabetic macular oedema, secondary glaucoma and persistent tractional retinal detachment (TRD) were assessed and compared between the two groups.

RESULTS

Complete reattachment of retina was achieved in 88.9% from the DM1 group and in 95.5% from the DM2 group and remained attached in follow-up. BCVA in DM2 group was significantly lower preoperatively (p = 0.04). Mean postoperative BCVA significantly improved in both studied groups, but it was more evident in eyes of type 2 diabetics compared to type 1 diabetics. In eyes in the DM1 group there was perceptible stabilisation of BCVA. Poor visual acuity or lack of improvement in BCVA in the DM1 group was related to preoperative subretinal haemorrhage in macular region, and TRD involving macula, whereas in the DM2 group-to preoperative subretinal haemorrhage and neovascular glaucoma. The postoperative structural changes (disruption of EZ and ELM) were observed more often in DM2 group, but had the greatest impact on BCVA in eyes of type 1 DM. Complications after PPV for PDR were rare and hadn't a significant influence on the final functional outcomes in both groups.

CONCLUSIONS

Functional improvement after PPV for severe features of proliferative diabetic retinopathy were more noticeable in patients with type 2 DM. Postoperative structural changes had more negative impact on BCVA in type 1 diabetics.

Use of Heavy Silicon Oil as Intraocular Tamponade for Inferior Retinal Detachment Complicated by Proliferative Vitreoretinopathy: A Multicentric Experience

INTRODUCTION

This is a multicentric study on the use of heavy silicon oil (HSO) as an intraocular tamponade for inferior retinal detachment (RD) complicated by proliferative vitreoretinopathy (PVR).

METHODS

139 eyes treated for RD with PVR were included in the study. 10 (7.2%) were affected by primary RD with inferior PVR, while 129 (92.8%) were affected by recurrent RD with inferior PVR. 102 eyes (73.9%) had received a silicon oil (SO) tamponade in a previous intervention prior to receiving HSO. Mean follow-up was 36.5 (standard deviation = 32.3) months.

RESULTS

The median interval between HSO injection and removal was 4 months (interquartile range: 3). At the time of HSO removal, the retina was attached in 120 eyes (87.6%), whereas in 17 eyes (12.4%), it had re-detached while the HSO was in situ. 32 eyes (23.2%) showed recurrent RD. A subsequent RD relapse was observed in 14.2% of cases with no RD at the time of HSO removal, and in 88.2% if an RD was present at the time of HSO removal. Advancing age showed a positive association with retinal attachment at the end of follow-up, while the risk of RD relapse at the end of the follow-up showed a significant negative association with HSO tamponade duration and with the use of SO rather than air or gas as post-HSO tamponade materials. Mean best corrected visual acuity was 1.1 logarithm of minimum angle of resolution at all follow-up time points. 56 cases (40.3%) needed treatment for elevated intraocular pressure (IOP), with which no clinically relevant variables were associated during follow-up.

CONCLUSION

HSO represents a safe and effective tamponade in cases of inferior RD with PVR. The presence of RD at the time of HSO removal is a negative prognostic factor for the development of a subsequent RD relapse. According to our findings, in cases of RD at the time of HSO removal, a short-term tamponade should definitely be avoided, in favor of SO. Special attention must be paid to the risk of IOP elevation, and patients should be closely monitored.

25-Gauge pars plana vitrectomy combined with air tamponade for primary rhegmatogenous retinal detachment

OBJECTIVE

This study was performed to evaluate the outcomes of 25-gauge (25-G) pars plana vitrectomy (PPV) with air tamponade for primary rhegmatogenous retinal detachment (RRD).

METHODS

This retrospective consecutive case series included 126 eyes of 125 patients with primary RRD who underwent 25-G PPV with air tamponade. The patients were followed up for at least 6 months following surgery. The main outcome measures were the primary and final anatomical success rates and postoperative complications.

RESULTS

The mean age of the 125 patients (80 men and 45 women) was 53.7 ± 10.0 years. The mean follow-up period was 8.3 ± 2.2 months (range, 6-18 months). Twenty-four eyes (19.0%) presented with high myopia, and 13 eyes (10.3%) were pseudophakic. Of the 126 eyes, 37 (29.4%) had inferior breaks, 2 (1.6%) had choroidal detachment, and 86 (68.3%) had macular detachment. The single- and final-operation success rates were 96.0% and 100%, respectively. Postoperative complications included macular hole formation in two eyes. During follow-up, secondary cataract surgery was performed in 27 (23.9%) of the 113 phakic eyes.

CONCLUSION

25-G PPV with air tamponade is effective and safe in treating selected patients with primary RRD with a high anatomical success rate.

Silicone oil residual after vitrectomy for rhegmatogenous retinal detachment

OBJECTIVE

To explore the presence of residual emulsified silicone oil (SO) droplets in patients with rhegmatogenous retinal detachment (RRD) and their possible risk factors.

METHODS

Patients who underwent primary pars plana vitrectomy with SO injection for RRD and SO removal at the same eye centre were included. Approximately 10 weeks after SO removal, B-scan ultrasonography was performed, and using ImageJ, the silicone oil index (SOI) was measured, and its possible correlations with other clinical factors were explored.

RESULTS

A total of 101 eyes were included. Residual SO particles were found in all the patients (100%), and the mean SOI was 4.04% ± 5.16% (range 0.06%-19.88%). Multiple linear regression revealed that, among all the clinical factors, axial length (AL) and ocular hypertension (intraocular pressure (IOP) > 21 mmHg or the use of antiglaucoma medications) before SO removal were positively and significantly associated with the SOI (all P < 0.05). Patients with ocular hypertension after SO removal had a higher SOI, a longer SO duration, a higher IOP before SO removal and a longer AL than those without (all P < 0.05).

CONCLUSIONS

Patients with a larger AL and higher IOP before SO removal were more prone to have more residual SO droplets, which might in turn lead to an elevated IOP. In these eyes, thorough irrigation or repeated fluid-air exchange might be necessary.

Air Tamponade for Rhegmatogenous Retinal Detachment With Inferior Breaks After 25-Gauge Pars Plana Vitrectomy: Technique and Outcome

To evaluate the outcomes of 25-guage (G) pars plana vitrectomy (PPV) with air tamponade for rhegmatogenous retinal detachment (RRD) with inferior breaks. This retrospective consecutive case series included fifty-two eyes of fifty-two RRD patients with inferior breaks who underwent 25-G PPV with air tamponade. These patients were followed up for at least 6 months following surgery. Primary and final anatomical success rates and postoperative complications were the main outcome measures. The mean age of the patients (39 men and 13 women) was 51.8 ± 11.8 years. There were 49 primary RRDs (94.2%) and three recurrent RRDs (5.8%). The mean follow-up period was 8.2 ± 1.6 months (range: 6–13 months). Sixteen eyes (30.8%) presented with high myopia, and six eyes (11.5%) were pseudophakic. Proliferative vitreous retinopathy grade was C1 in four eyes (7.7%). Of the 52 eyes, two (3.8%) were complicated with choroidal detachment, and forty (76.9%) had the macula detached. The single- and final-operation success rates were 96.2% and 100%, respectively. During follow-up, secondary cataract surgery was performed in eight eyes (17.4%) of the 46 phakic eyes. 25-G PPV with air tamponade is effective in treating selected RRD patients with inferior breaks. Patients can benefit from early visual recovery and less complications.

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.

Characteristics of Silicone Oil Emulsification After Vitrectomy for Rhegmatogenous Retinal Detachment: An Ultrasound Biomicroscopy Study

Purpose: To investigate the characteristics of silicone oil (SO) emulsification after vitrectomy for rhegmatogenous retinal detachment (RRD) and possible correlations with clinical factors.

Methods: Patients who underwent primary pars plana vitrectomy with SO injection for RRD followed by SO removal at the Eye and ENT Hospital of Fudan University between January 2016 and January 2020 were included. Ultrasound biomicroscopy (UBM) images of the anterior segment were taken before SO removal. Eight signs of SO emulsification in the UBM images were graded as 1 (present) or 0 (not present) and the grades for all signs in each eye were summed. Correlations between SO emulsification grade and clinical factors were determined.

Results: A total of 118 patients (118 eyes) were enrolled in this study. Emulsified SO particles were found in all 118 eyes (100%). The eight signs were more frequently detected in the superior part of the eye. The mean total SO emulsification grade was 19.99 ± 12.98 (range: 1–36). Younger age and male (both P < 0.05) were associated with higher total SO emulsification grade. Patients with intraocular pressure (IOP) > 21 mmHg or the use of antiglaucoma medications at the time of SO removal had a higher total SO emulsification grade, were younger, and were more frequently male (all P < 0.05) than patients without ocular hypertension.

Conclusions: UBM could play an important role in the diagnosis and grading of SO emulsification. Younger patients and males are more prone to SO emulsification, which may lead to elevated IOP.

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.

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.

Analysis of the Changes in Retinal Thickness in Eyes Undergoing Vitrectomy with Silicone Oil Tamponade

Purpose: To investigate changes in the retinal layer thickness in rhegmatogenous retinal detachment (RRD) and intraocular foreign body (IOFB) patients undergoing successful pars plana vitrectomy (PPV) with silicone oil tamponade. Methods: This retrospective study included 28 eyes of 28 patients (RRD: 24 patients; IOFB: 4 patients) that were successfully repaired with PPV with silicone oil tamponade. The thickness measurements of the total retina, retinal nerve fiber layer (RNFL), and ganglion cell-inner plexiform layer (GC-IPL) were performed with swept-source optical coherence tomography in nine Early Treatment Diabetic Retinopathy Study subfields, using the wide three-dimensional mode before and after silicone oil tamponade removal. The measurements were compared and differences were analyzed with respect to normal fellow eyes. Results: The RNFL and GC-IPL thickness measurements decreased remarkably as the silicone oil tamponade period progressed, compared with the thickness of the total retinal layer. The average thicknesses of the total retina, RNFL, and GC-IPL were significantly greater in eyes in which the silicone oil had been removed than in those in which the silicone oil remained. Conclusions: Silicone oil tamponade can change the thickness of the retina layer. The longer the silicone oil is tamponaded, the more significant the reduction in thickness of the inner retinal layer.

Trabeculectomy with OloGen versus Mitomycin C for the Treatment of Silicone Oil-Induced Glaucoma

AIM

To compare the intraocular pressure-lowering effect and success rate of trabeculectomy with OloGen to that of trabeculectomy with mitomycin C (MMC) in cases of silicone oil-induced glaucoma.

MATERIALS AND METHODS

Forty eyes of forty patients with elevated intraocular pressure (IOP) after vitrectomy and silicone oil injection (followed by silicone oil removal) were assigned to two groups. Group A included 20 cases who underwent trabeculectomy with OloGen, while group B cases contained 20 cases undergoing trabeculectomy with MMC. The follow-up period was 24 months. Patients enrolled had IOP > 21 mmHg despite being on antiglaucoma medications.

RESULTS

The mean postoperative IOP reduction was lower in group A than in group B at all follow-up visits, but this difference was not statistically significant (p > 0.05). Moreover, group A and B patients were found to be similar as regards the need for postoperative antiglaucoma medications on all follow-up visits. The Kaplan-Meier survival analysis curves for the two groups revealed slightly higher success rates in group B than in group A. However, these differences were not statistically significant for both qualified success (IOP ≤ 21 mmHg with or without antiglaucoma medications) and complete success (IOP ≤ 21 mmHg without antiglaucoma medications). There was no significant difference in the postoperative complication rate between the two groups.

CONCLUSION

OloGen implant lowers IOP to a similar extent as MMC when combined with trabeculectomy for the treatment of silicone oil-induced glaucoma, and with comparable success rates. The rate of postoperative complications is similar for OloGen implantation and MMC.

Silicone Oil Droplets in the Schlemm's Canal: A Surprise during Prolene Hemi-gonioscopy-assisted Transluminal Trabeculotomy (Hemi-GATT)

Aim and objective

To report a case with emulsified silicone oil (SO) droplets in the Schlemm's canal (SC), encountered during prolene hemi-gonioscopy-assisted transluminal trabeculotomy (hemi-GATT).

Background

In cases with a history of previous pars plana vitrectomy (PPV) with SO tamponade and then SO removal; glaucoma might occur secondary to the presence of emulsified SO droplets. Minimal invasive glaucoma surgeries targeting trabecular meshwork such as GATT surgery might be an ideal treatment option in these cases.

Case description

A 57-year-old man presented with uncontrolled intraocular pressure (IOP) and topical anti-glaucoma drug intolerance in his left eye. The patient had a history of PPV with SO tamponade and then intravitreal SO removal 5 years ago. He had a history of Ahmed glaucoma valve (AGV) implantation 2 years ago for the treatment of secondary glaucoma but he was still using topical anti-glaucoma medication. However, IOP was measured as 17 in the left eye. Hemi-gonioscopy-assisted transluminal trabeculotomy was performed successfully to get the patient off medication. During the surgery, SC was full of SO droplets.

Conclusion

The presence of SO droplets in the SC might contribute to the development of secondary glaucoma after PPV and SO removal. This might be another surgical indication for GATT surgery in these risky eyes.

How to cite this article

Aktas Z, Bölük CE, Gurelik G. Silicone Oil Droplets in the Schlemm's Canal: A Surprise during Prolene Hemi-gonioscopy-assisted Transluminal Trabeculotomy (Hemi-GATT). J Curr Glaucoma Pract 2021;15(1):40–43.

Intraocular pressure change with face-down positioning after macular hole surgery

This study evaluated changes in intraocular pressure (IOP) with face-down positioning (FDP) following surgical treatment of idiopathic macular hole. We retrospectively reviewed the records of 130 patients diagnosed with idiopathic macular hole who underwent pars plana vitrectomy (PPV) with intravitreal gas injection after fluid-gas exchange. We analyzed IOP changes in both eyes following FDP over the course of 7 days. The mean IOP of the operated eyes was 14.98±2.95 mmHg preoperatively and 16.82±3.12 and 15.57±6.10 mmHg on postoperative days 2 and 7, respectively. In contralateral eyes, the mean IOP changed from 14.78±3.15 mmHg preoperatively to 16.27±1.87 and 14.40±4.14 mmHg on postoperative days 2 and 7, respectively. On postoperative day 2, the IOP increased in both eyes compared to the preoperative values, but the increase was significant only in operated eyes (p = 0.039). In contralateral eyes, the IOP on postoperative day 7 was significantly decreased compared with that on postoperative day 2 (p = 0.021) and in eyes with an axial length ≥ 23.0 mm, compared with the preoperative values (p = 0.042). The IOP of the operated eyes on postoperative day 7 was higher than that of the contralateral eyes (p = 0.039). Based on a short-term follow-up, FDP after PPV with intravitreal gas tamponade for the treatment of idiopathic macular hole may cause IOP elevation not only in the operated, but also in the contralateral eyes; the IOP increase in contralateral eyes was not as significant as that in operated eyes and was not maintained over 7 days after surgery; the IOP change seems to be affected by axial length and lens status.

Individualized transscleral cyclophotocoagulation as the initial surgical intervention for medically uncontrolled glaucoma after blunt trauma

AIM

To investigate the safety and feasibility of individualized transscleral cyclophotocoagulation (TSCPC) as the initial non-incisional surgical intervention for medically uncontrolled glaucoma after blunt trauma.

METHODS

The therapy records were reviewed of medically uncontrolled traumatic glaucoma after blunt trauma treated with TSCPC in a single hospital between January 2014 and December 2018. Thirty-one patients (31 eyes) received individualized TSCPC after ultrasound biomicroscopy and gonioscopy examination to localize and quantify the injured quadrants of the anterior chamber angle. In addition to the number of IOP lowing drugs, visual acuity (VA), IOP, inflammation and hemorrhage in the anterior chamber were analyzed at 1 day, 3 weeks and 3 months after operation, respectively. Success was defined as the IOP was not more than 21 mmHg.

RESULTS

Compared with the data of pre-operation, constituent ratio of VA had no significant difference at 3 weeks (χ² = 0.56, p > 0.75). At 3 months the average IOP was 22.2 ± 6.8 mmHg, which was significantly lower than that of pre-operation (46.6 ± 5.6 mmHg) (t = 19.818, p < 0.001). No IOP lowing drug was needed in 12 eyes, and more than three kinds of drugs were still needed in five eyes. The average number of medications decreased to 1.2 ± 1.2 (χ² = 93.496, p < 0.001). The complete success rate was 38.7% and the relative success rate (combined with no more than two kinds of drugs) was 83.9% at 3 months.

CONCLUSIONS

Individualized TSCPC could be applied as an initial non-incisional surgical intervention to treat traumatic glaucoma refractory to the medicine therapy.

Intraocular pressure changes during and after silicone oil endotamponade (Review)

Silicone oil (SIO) has rapidly become an indispensable adjunct in vitreoretinal surgery. Constant improvements in purity and also in viscosity have not totally prevented specific complications that may occur during endotamponade. Results of in vitro studies that suggested that higher viscosity silicone oil might be superior in terms of stability and safety are confirmed in real life only if endotamponade lasts for more than 6 months. Intraocular pressure changes induced by the silicone oil endotamponade or oil extraction are documented from its very first use and are potentially threatening vision. The purpose of this review is to update current knowledge on the incidence, risk factors, pathogenesis, and management of secondary silicone oil glaucoma. Also, in a retrospective evaluation on cases with complex retinal detachments that underwent 23G vitrectomy and high viscosity SIO endotamponade, we have noticed that a considerable number of cases developed significant intraocular pressure changes during SIO endotamponade and after SIO removal, especially in early postoperative period.

Supine positioning after vitrectomy for rhegmatogenous retinal detachments with inferior retinal breaks

Background

To evaluate the effectiveness of face up position (FUP) following pars plana vitrectomy (PPV) and silicone oil injection in cases of rhegmatogenous retinal detachment (RRD) with multiple peripheral and inferior breaks.

Method

Thirty-two eyes of 32 patients with RRD due to multiple peripheral breaks were managed with PPV and silicone oil as endotamponade. Postoperatively, all patients were instructed to assume face up (supine) position for at least 10 days. Silicone oil was removed 3 to 6 months postoperatively in eyes with attached retina and the patients were followed up for 6 months.

Results

Thirty eyes (94%) got a successful attachment of the retina and remained attached after silicone oil removal. One case showed lower redetachment under silicone oil while the other case showed recurrent RRD after silicone oil removal.

Conclusion

Although postoperative FUP is not a popular one, it is effective in the treatment of RRD with peripheral breaks whatever the number or the distribution of these breaks. This may in some way or another change the traditional trends of postoperative positioning after vitrectomy for RRD.

Gonioscopy-assisted Transluminal Trabeculotomy (GATT) in Patients With Secondary Open-Angle Glaucoma Following Vitreoretinal Surgery

PURPOSE

To examine the short-term efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) in a series of patients who developed glaucoma following vitreoretinal surgery.

PATIENTS AND METHODS

Retrospective case series of consecutive patients aged above 18 years with secondary open-angle glaucoma following vitreoretinal surgery who had undergone GATT between January 2015 and June 2019. Eyes were excluded if there is<1 month of follow-up or glaucoma before vitreoretinal surgery.

RESULTS

Eight eyes of 8 patients were included, with age range 18 to 72 years (median 43.5 y). Mean pretreatment intraocular pressure (IOP) was 32.7±5.1 mm Hg with a mean of 4.8±0.9 medications. Following GATT, mean IOP improved to 13.6±1.8 mm Hg (P<0.001) with a reduction to 1.6±1.4 medications after a mean follow-up of 8.6 months (range 1 to 25 mo). Five of the 8 eye (62.5%) had silicone oil in the vitreous cavity during GATT, none of which had concurrent oil removal.

CONCLUSIONS

GATT is a safe and effective procedure for eyes with secondary open-angle glaucoma following vitreoretinal surgery. Further studies are needed to elucidate long-term benefits of angle surgery on eyes with high pressure following vitreoretinal surgery.

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.

Incidence and risk factors for intraocular pressure rise after transconjunctival vitrectomy

Purpose

To study the incidence and risk factors of raised intraocular pressures (IOPs) in the follow-up of transconjunctival sutureless vitrectomy (TSV).

Methods

A retrospective observational study was performed on 635 patients who underwent TSV under a single surgeon. The IOPs were recorded using a calibrated non-contact tonometer at seven postoperative visits, viz., day 1, 7 and 1, 3, 6 months, and 1 day and 1 month following silicone oil removal.

Results

IOP rise was seen in 24.25% (154) out of the 635 eyes studied. Among patients under 50 years of age, 37.73% had an IOP rise, compared to 21.55% above 50 years (Odds Ratio 2.206). Among males, 30.32% had an IOP rise, as compared to 15.98% females (OR 2.287). In eyes with retinal detachment, 49.16% had raised IOP (OR 5.435), and 24.05% with proliferative diabetic retinopathy (OR 1.780), as opposed to 15.38% with macular hole and 12.32% with epiretinal membrane. This was statistically significant (P < 0.001). In eyes with silicone oil, 34.9% developed a rise in IOP (OR 2.738) as compared to 11.94% of other surgeries (OR 0.697). This was statistically significant (P < 0.001).

Conclusion

We observed an increase in IOP postoperatively, more in those under 50 years, males and patients undergoing surgery for RD and PDR.

Efficacy And Safety Of Travoprost Versus Timolol To Treat Early-Onset Ocular Hypertension Secondary To Vitrectomy: A Randomized Trial

Purpose

To evaluate the efficacy and safety of travoprost 0.004% versus timolol 0.5% as an initial intraocular pressure (IOP)-lowering medication for ocular hypertension secondary to vitrectomy.

Patients and methods

We performed a randomized, controlled, observer-blinded clinical trial in the Eye & ENT Hospital of Fudan University in China. This trial was registered at www.chictr.org.cn (ChICTR1800014942) before patient enrollment. Seventy-nine adults with IOP of 25–45 mmHg secondary to vitrectomy in the latest one month were enrolled and randomized to receive travoprost 0.004% or timolol 0.5%. More drugs were administered to patients with IOP > 25 mmHg during follow-up.

Results

The mean IOP reduction at day 1 was −10.97 mmHg in the timolol group and −15.02 mmHg in the travoprost group (P = 0.006); no significant difference was observed between the groups at later time points. The number of IOP-lowering medications at day 21 was 0.64 in the timolol group and 1.15 in the travoprost group (P = 0.038), while no significant differences were observed at other time points. The proportion of single IOP-lowering medications used during the 4-week follow-up was 72.73% in the timolol group and 68.42% in the travoprost group (P = 0.692). Inflammation scores were not significantly different in the two groups at any time point. Increased ocular hyperemia occurred in 8 patients (19%) in the travoprost group and none in the timolol group (P = 0.005). There were no significant differences in other adverse events between the two groups. After logistic regression model analysis, IOP ≥ 30 mmHg, inflammation score ≥ 2, and silicone oil as tamponade were found to be the factors with significant effects on the number of IOP-lowering medications used during the 4-week follow-up.

Conclusion

Travoprost and timolol have similar efficacy and safety for treating ocular hypertension secondary to vitrectomy.

Safety and efficacy of paediatric silicone Ahmed glaucoma valve (AGV) in adult eyes with post-VR surgery glaucoma

PURPOSE

To compare the safety and efficacy of the FP8 AGV (paediatric) with the standard FP7 AGV in adult post-vitreoretinal (VR) surgery glaucoma.

METHODS

We included 45 consecutive eyes with post-VR surgery glaucoma implanted with either FP8 (n = 28) or FP7 (n = 17) AGV between 2008 and 2016. The data analysed included visual acuity (VA), intraocular pressure (IOP), complications, interventions, and outcomes.

RESULTS

Mean age (p = 0.24), mean baseline VA (p = 0.77), preoperative IOP (p = 0.41), number of antiglaucoma medications (p = 0.92), and previous surgeries (p = 0.16) were comparable in the two groups. The number of eyes with previous belt buckle was significantly higher (p < 0.001) in the FP8 group (17/28) compared with the FP7 group (2/17), indicating space constraint and scarred conjunctiva. The median follow-up (25th, 75th percentile) was 14.7 (9.1, 25.3) months in the FP7 and 9.8 (6.4, 34.7) months in the FP8 groups (p = 0.62). Postoperatively, the median VA (p = 0.24), the mean IOP at final follow-up (p = 0.15), and median number of AGM (p = 0.99) were comparable in both the groups. The median percentage drop in IOP (95% confidence interval) with the FP7 implant was 55% (43.70%) and with FP8 implant was 53.8% (25, 73), (p = 0.20). None in the FP7 group failed, while three eyes in the FP8 group failed. During the study period, two eyes in the FP8 group had tube exposure that was surgically managed. None of the eyes had implant exposure or loss of light perception.

CONCLUSION

Use of the paediatric FP8 AGV in adult post-VR surgery glaucoma eyes with severe conjunctival scarring and limited subconjunctival space resulted in reasonable IOP control compared with the standard FP7 AGV implant. There were no eyes with implant extrusion.

The effect of multiple vitrectomies and its indications on intraocular pressure

Background

To assess the relationship between different indications for trans pars plana vitrectomies (PPV’s) and the intraocular pressure (IOP), and the effect of multiple PPV’s on the IOP. We also examined whether there were differences in the number of IOP-lowering medications or surgeries before and after PPV.

Methods

A retrospective study including all patients that underwent at least one PPV in the period from 2001 till 2014 at our clinic. Medical records of all patients were reviewed and clinically relevant data were entered in a database. Generalized estimating equations models for repeated measurements were used to examine the effect of the number of PPV’s on the IOP and on the risk of undergoing glaucoma surgery, for each of the indications for PPV.

Results

Of 1072 PPV’s 447 eyes fulfilled the inclusion criteria. The IOP increased with 3.0 mmHg after a PPV with indication retinal detachment (p < 0.001), but remained stable after PPV for epiretinal membrane (p = 0.555), macular hole (p = 0.695), and vitreous hemorrhage (p = 0.787). At the end of the follow-up period the number of IOP-lowering medications was significantly higher compared to baseline, except in the macular hole group (p = 0.103). Also, the number of eyes that underwent glaucoma surgery was significantly higher compared to the fellow (not-operated) eyes (p < 0.001). There was a significant association between the number of PPV’s and the final IOP for the indication retinal detachment (p = 0.009), and between the number of PPV’s and glaucoma surgery (odds ratio [95% confidence interval]: 2.60 [1.62–4.15]).

Conclusions

The IOP rises significantly after PPV with indication retinal detachment. This association was not found for other indications for PPV. Also, the risk of IOP-lowering surgeries was higher after PPV, but not different between the PPV indications. The IOP should be monitored carefully after PPV, since there may be a higher risk of secondary glaucoma.

Estimating three-dimensional outflow and pressure gradients within the human eye

In this paper we set the previously reported pressure-dependent, ordinary differential equation outflow model by Smith and Gardiner for the human eye, into a new three-dimensional (3D) porous media outflow model of the eye, and calibrate model parameters using data reported in the literature. Assuming normal outflow through anterior pathways, we test the ability of 3D flow model to predict the pressure elevation with a silicone oil tamponade. Then assuming outflow across the retinal pigment epithelium is normal, we test the ability of the 3D model to predict the pressure elevation in Schwartz-Matsuo syndrome. For the first time we find the flow model can successfully model both conditions, which helps to build confidence in the validity and accuracy of the 3D pressure-dependent outflow model proposed here. We employ this flow model to estimate the translaminar pressure gradient within the optic nerve head of a normal eye in both the upright and supine postures, and during the day and at night. Based on a ratio of estimated and measured pressure gradients, we define a factor of safety against acute interruption of axonal transport at the laminar cribrosa. Using a completely independent method, based on the behaviour of dynein molecular motors, we compute the factor of safety against stalling the dynein molecule motors, and so compromising retrograde axonal transport. We show these two independent methods for estimating factors of safety agree reasonably well and appear to be consistent. Taken together, the new 3D pressure-dependent outflow model proves itself to capable of providing a useful modeling platform for analyzing eye behaviour in a variety of physiological and clinically useful contexts, including IOP elevation in Schwartz-Matsuo syndrome and with silicone oil tamponade, and potentially for risk assessment for optic glaucomatous neuropathy.

Influence of Vitrectomy-related Factors on the Outcome of Ahmed Glaucoma Valve Implantation

Purpose

To evaluate the outcome of Ahmed glaucoma valve (AGV) implantation in eyes with refractory secondary glaucoma following pars plana vitrectomy (PPV) and the associated prognostic factors.

Methods

A total of 146 eyes in 146 patients who underwent AGV implantation after PPV (followed up for ≥1 year) were included. AGV implantation was considered successful when the intraocular pressure (IOP) was 6 to 21 mmHg regardless of using IOP-lowering medication. The hazard ratios (HRs) associated with surgical failure were determined with Cox proportional analysis.

Results

The most common cause for PPV was complications of proliferative diabetic retinopathy (50%). The mean and peak IOPs between PPV and AGV implantation were 26.9 ± 6.6 and 35.9 ± 10.2 mmHg, respectively. AGV implantation was performed on average 18.7 months after PPV, and its overall success rate was 80.1% during a mean follow-up period of 43.6 months. In multivariate analyses, rubeosis observed before AGV implantation (HR, 4.07; 95% confidence interval, 1.57 to 10.6; p = 0.004) and higher peak IOP before AGV (HR, 1.04; 95% confidence interval, 1.00 to 1.07; p = 0.034) were predictive of failure. However, no PPV-related factors were associated with the surgical outcome of AGV implantation.

Conclusions

The outcome of AGV implantation is good in refractory glaucoma following PPV. Rubeosis after PPV and higher peak IOP before AGV are risk factors for poor outcomes. Patients who undergo PPV should be followed for the development of rubeosis and IOP control.

Air tamponade and without heavy liquid usage in pars plana vitrectomy for rhegmatogenous retinal detachment repair

AIM

To report the results of rhegmatogenous retinal detachment (RRD) repair after pars plana vitrectomy (PPV) without operative use of heavy liquid, and utilizing air tamponade in selected cases.

METHODS

RRD patients without severity of proliferative vitreoretinopathy C₂ or more underwent PPV without operative use of heavy liquid, and utilizing air tamponade were consecutively enrolled. Alternative postoperative facedown position or lateral position was required for 3-5d.

RESULTS

Totally 36 eyes of 36 patients (24 males, 66.7%) aged 53.8±10.9y underwent this modified surgery. The mean number of retinal break was 2.1±1.3. Most of the eyes (29, 80.6%) had retinal detachment involving more than one quadrant. Twenty-two (61.1%) eyes with cataract had combined phacoemulsification and intraocular lens implantation. The mean follow up time was 4.6±1.8mo. Two eyes with retinal redetachment underwent a second retinal repair surgery with silicone oil tamponade, yielding the primary reattachment rate to 94.4% (34/36). Six (16.7%) eyes had intraocular pressure higher than 25 mm Hg. The visual acuity (logMAR) improved from 0.98±0.74 preoperatively to 0.52±0.31 postoperatively (P<0.001).

CONCLUSION

The success rate of this modified retinal repair surgery is comparable with traditional surgery. This technique can be considered for certain retinal detachment patients, since its apparent advantages included lower surgical complications, reduced surgery expenditure, shorter time for postoperative facedown position, and avoiding silicone oil removal surgery.

Goniosynechialysis for secondary angle closure glaucoma in aphakic patient after pars plana vitrectomy

Purpose

To report the effectiveness of Goniosynechialysis (GSL) treating elevated intraocular pressure (IOP) in an aphakic eye with peripheral anterior synechiae (PAS) formation after vitrectomy.

Observations

A 39-year-old gentleman with history of lamellar keratoplasty for corneal ectasia and blunt trauma to the right eye necessitating vitrectomy and lensectomy presented to our glaucoma unit with a secondary angle closure and an IOP of 50 mmHg. This was successfully treated with GSL and one year after surgery, the patient maintains a normal IOP without the use of medication.

Conclusions and importance

GSL may successfully restore angle integrity in aphakic patients following vitreoretinal surgery and avoid the need for a glaucoma drainage device.

Ahmed Glaucoma Valves versus EX-PRESS Devices in Glaucoma Secondary to Silicone Oil Emulsification

Objective

To evaluate and compare the clinical effects of Ahmed glaucoma valves (AGVs) and EX-PRESS implants on glaucoma secondary to silicone oil (SO) emulsification.

Methods

A retrospective case-series study was designed. A total of 23 eyes with late intraocular pressure (IOP) elevation secondary to SO emulsification were included in the study. Antiglaucoma surgery with implantation of AGVs or EX-PRESS devices was performed. Pre- and postoperative ocular parameters were recorded at each visit during a 1-year follow-up period. The rates of complete success (IOP < 21 mmHg without medication) and qualified success (IOP < 21 mmHg with ≤3 glaucoma medications) were analyzed.

Results

A total of 14 eyes underwent AGV implantation, and 9 underwent EX-PRESS implantation. The mean IOP and number of medications used at the last follow-up decreased significantly compared with that before surgery (P < 0.001). The total success rate for all eyes including complete success (7/23) and qualified success (7/23) was 60.9% (14/23) at 1 year. The total success rate in the AGV group was 78.6% (11/14), whereas it was 33.3% (3/9) in the EX-PRESS group; the difference between the 2 groups was significant (P < 0.05).

Conclusion

For glaucoma secondary to SO emulsification, glaucoma implants could be effective at lowering IOP, and AGVs might produce better outcomes than EX-PRESS devices.

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

PURPOSE

Aim of this study was to compare outcome of four different surgical modalities for management of persistent glaucoma after silicone oil removal in vitrectomized eyes.

METHODS

This is a prospective comparative study, carried out on a cohort of 41 eyes (41 patients). Patients were randomly allocated to Group A (trabeculectomy), Group B (deep sclerectomy), Group C (Ahmed valve), or Group D (Ex-Press Minishunt). Postoperatively, all patients were followed regularly at 1 day, 1 week, 1, 3, and 6 months, and 1 year for intraocular pressure evaluation.

RESULTS

Postoperatively, there was significant drop in intraocular pressure in each group, and significant difference between the four groups regarding drop and percentage drop in intraocular pressure, with Group C showing the highest mean percentage drop in intraocular pressure, whereas Group B with the least. Success rate was 100% with Ex-Press minishunt, 80% with Ahmed valve, and 50% for each of trabeculectomy and deep sclerectomy. Hypotony occurred in 50% with Ahmed valve and 40% with trabeculectomy, whereas glaucoma occurred in 50% with deep sclerectomy and 30% with trabeculectomy.

CONCLUSION

For controlling persistent glaucoma after silicone oil removal in our work, Ex-Press minishunt had the highest complete success rate with no postoperative complications.

Intraocular pressure 1 year after vitrectomy in eyes without a history of glaucoma or ocular hypertension

Objective

The aim of this study was to investigate the incidence, risk factors, and treatment of elevated intraocular pressure (IOP) 1 year after vitrectomy in eyes without a history of glaucoma or ocular hypertension.

Patients and methods

This retrospective study comprised 256 eyes from 256 consecutive patients without a history of glaucoma or ocular hypertension who underwent vitrectomy and were followed up for 1 year. The incidence of elevated IOP at 1 year after vitrectomy was calculated. We compared the characteristics of patients with or without elevated IOP to identify possible risk factors for elevated IOP. The treatments used to control IOP were recorded and analyzed.

Results

A total of 50 patients (19.5%) had elevated IOP after vitrectomy at the 1-year follow-up. Tamponade was a significant risk factor for elevated IOP (P<0.05). The cumulative rates of elevated IOP in eyes with air, balanced salt solution, sulfur hexafluoride, perfluoropropane (C3F8), and silicone oil as the tamponade were 0, 10.8%, 5.9%, 19.8%, and 28.4%, respectively (P<0.05). About 68% of cases of elevated IOP occurred within 1 month after vitrectomy. At 1 year after vitrectomy, 29 patients (58.0%) had stopped their IOP-lowering drugs and 21 (42.0%) patients were continuing these drugs. About 65% of ocular hypertension patients who received silicone oil tamponade had not stopped IOP-lowering drugs; this rate was significantly greater than that of ocular hypertension patients who received C3F8 tamponade (18.2%, P<0.05).

Conclusion

Elevated IOP is a common complication after vitrectomy. Silicone oil tamponade was associated with greater risk of elevated IOP and had long-term effects on IOP. Drugs and surgery were used to control IOP, and some patients required long-term IOP-lowering therapy.

EFFECT OF BODY POSITION ON INTRAOCULAR PRESSURE IN SILICONE OIL TAMPONADE EYES

PURPOSE

To investigate the effect of body position on intraocular pressure (IOP) in silicone oil tamponade eyes.

METHODS

This prospective study included 18 eyes from 18 silicone oil tamponade patients and 24 eyes from 24 healthy subjects. Intraocular pressures were measured by Accupen Applanation Tonometer sitting with face forward, sitting with face down, supine, nondependent lateral decubitus, dependent lateral decubitus, and prone positions. The IOPs in each position and the magnitudes of IOP change were compared between the silicone oil and normal groups.

RESULTS

In both groups, the IOPs in sitting positions were significantly lower than that of each recumbent position. The IOPs were highest in prone among all positions. No significant difference was found between IOPs of each group in each position. Between both groups, the IOP elevations in each position had no statistical difference compared with sitting with face forward.

CONCLUSION

The IOP is lowest in the sitting position and highest in the prone position in both silicone oil and normal groups. Between both groups, the amount of IOP elevations is equivalent in each position compared with sitting with face forward. Ophthalmologists should be aware that IOP is higher in the prone position and that it should be monitored accordingly.

Trabeculectomy Versus Ex-Press Glaucoma Filtration Device in Silicomacrophagocytic Open Angle Glaucoma Secondary to Silicone Oil Emulsification

Purpose:

To compare the outcomes of Ex-PRESS device implantation versus trabeculectomy in patients with ocular hypertension after pars plana vitrectomy and silicone oil injection (SOI).

Materials and Methods:

Twenty-six consecutive eyes with ocular hypertension after pars plana vitrectomy and SOI were included in this study and randomized to one of two groups: A group treated with Ex-PRESS (model P50) placed under a scleral flap (Ex-PRESS group), and a group treated with trabeculectomy (trabeculectomy group). Complete success (intraocular pressure [IOP] <21 mmHg without medication) and qualified success rates (IOP <21 mmHg with one or two glaucoma medications) at 2 years postoperatively were analyzed. Between-groups comparison was performed with the Mann-Whitney U-test for continuous variables, and Fischer exact test for categorical data. Success rates between groups were compared using Kaplan-Meier life analysis and the log-rank test. P < 0.05 was considered statistically significant.

Results:

In the Ex-PRESS group, complete success was achieved in 73% eyes and qualified success in 81.8% of eyes. In the trabeculectomy group, complete success was achieved in 40% and qualified success was achieved in 60% of eyes. The difference in mean IOP between groups was statistically significant from the 3^rd postoperative month onward (P = 0.007 at 3 months, P = 0.003 at 6 months, and P = 0.03 at 24 months).

Conclusion:

Ex-PRESS implantation was more effective than trabeculectomy in controlling IOP in ocular hypertensives after pars plana vitrectomy and SOI, but the surgical technique may require improvement.

Goldmann Applanation Tonometry versus Dynamic Contour Tonometry after Vitrectomy with Silicone Oil Endotamponade

PURPOSE

To evaluate the agreement of intraocular pressure (IOP) measurements using dynamic contour tonometry (DCT) and Goldmann applanation tonometry (GAT) in eyes after vitrectomy with silicone oil endotamponade and controls.

METHODS

In this prospective comparative study, IOP was measured with GAT and DCT in 30 eyes with oil endotamponade 1-3 days after vitrectomy and 40 untreated controls. In addition, ocular pulse amplitude (OPA), corneal pachymetry (CCT), and axial length (AL) were measured.

RESULTS

GAT values in the oil group were significantly higher compared to control eyes (mean GAT oil 13.6 ± 5.1 mmHg; mean GAT control 10.8 ± 2.1 mmHg; p = 0.003). There was no significant difference in DCT measurements (mean DCT oil 12.0 ± 4.1 mmHg; mean DCT control 11.9 ± 2.9 mmHg; p = 0.9). This led to a significant difference of GAT-DCT between the oil and control group (mean difference of GAT-DCT oil 1.6 ± 4.7 mmHg; mean difference of GAT-DCT control -1.1 ± 2.6 mmHg; p = 0.004). The difference between GAT and DCT was negatively correlated with the mean IOP measured by both methods (r = -0.36, p = 0.02) and positively correlated with CCT only in the control group (r = 0.36, p = 0.02), as well as to AL only in the oil group (r = 0.46, p = 0.01). The OPA did not differ significantly between groups.

CONCLUSION

GAT and DCT showed a good agreement in control eyes. The difference of GAT and DCT is significantly changed in eyes after vitrectomy with silicone oil endotamponade. Our findings suggest that GAT overestimates IOP in this situation.

Development of ocular hypertension secondary to tamponade with light versus heavy silicone oil: A systematic review

Aim:

The intraocular silicone oil (SO) tamponades used in the treatment of retinal detachment (RD) have been associated with a difference ocular hypertension (OH) rate. To clarify, if this complication was associated to use of standard SO (SSO) versus heavy SO (HSO), we performed a systematic review and meta-analysis of comparative study between two kind of SO (standard or light vs. heavy) for the treatment of RD and macular hole, without restriction to study design.

Materials and Methods:

The methodological quality of two randomized clinical trials (RCTs) were evaluated using the criteria given in the Cochrane Handbook for Systematic Reviews of Intervention, while three non-RCTs were assessed with the Newcastle-Ottawa Scale and Strengthening the Reporting of Observational Studies in Epidemiology checklists. We calculated Mantel-Haenszel risk ratio (RR) with 95% confidence intervals (95% CIs). The primary outcome was the rate of patients with OH treated with SSO compared to HSO.

Results:

There were a higher number of rates of OH in HSO compared to SSO. This difference was statistically significant with the fixed effect model (Mantel-Haenszel RR; 1.55; 95% CI, 1.06–2.28; P = 0.02) while there was not significative difference with the random effect model (Mantel-Haenszel RR; 1.51; 95% CI, 0.98–2.33; P = 0.06).

Conclusion:

We noted a trend that points out a higher OH rate in HSO group compared to SSO, but this finding, due to the small size and variable design of studies, needs to be confirmed in well-designed and large size RCTs.

Long-term outcomes of glaucoma drainage devices for glaucoma post-vitreoretinal surgery with silicone oil insertion: a prospective evaluation

PURPOSE

To evaluate long-term success of the Ahmed glaucoma valve (AGV) for refractory glaucoma after vitreoretinal surgery with silicone oil insertion.

METHODS

Prospective non-comparative evaluation of patients who underwent AGV insertion for management of post-vitreoretinal surgery glaucoma, post-silicone oil removal. Intraocular pressure (IOP), visual acuity, and glaucomatous neuropathy status were evaluated preoperatively and at multiple follow-up visits postoperatively. Success, using Kaplan-Meier analysis, was determined at the 12-month follow-up visit and at the last follow-up. Factors associated with failure were analysed.

RESULTS

Twenty-seven eyes of 27 patients with a mean age of 28.3 ± 15.2 years underwent a superior AGV implantation. The average follow-up after AGV implantation was 17.11 ± 8.36 months (range: 9-60 months). Kaplan-Meier survival analysis revealed a 62 % success at 12 months and 37 % at 5 years. A 48 % rate of complications was noted, 22 % of which were vision-threatening. Factors analysed, including patient age, interval between vitreoretinal surgery and silicone oil removal, interval between vitreoretinal surgery and AGV implantation, and phakic status, were not found to be associated with higher failure rates.

CONCLUSION

Long-term success of AGV implantation for glaucoma after vitreoretinal surgery with silicone oil insertion is better than that reported for trabeculectomy, though complication rates remain high.

Passive removal of silicone oil through 23 gauge transconjunctival sutureless vitrectomy system

Objective:

To study the outcomes of passive removal of silicone oil by 23 Gauge Transconjunctival Sutureless Vitrectomy System.

Methods:

This prospective, consecutive case series study was conducted at Ophthalmology Department Unit I, Dow University of Health Sciences, Civil Hospital Karachi from January 2011 to December 2014. Only psuedophakic eyes with silicone oil temponade were selected. Main outcome measures were intra ocular pressure, time taken for removal of silicone oil, per operative and post operative complications. Pre and post operative IOP was compared by using two-tailed paired t-test and mean values with standard deviation were computed using difference of 95% confidence interval. Chi square test was applied for correlation of different variables. P-value of less than 0.05 was considered statistically significant.

Results:

Out of 79 patients who underwent passive ROSO, 38 (48.1%) were males. Mean age of patients was 47.5±7.1 (sd) years. Mean time taken for passive ROSO was 7.31±2.41 (sd) minutes. Pre and post operative intra ocular pressure shows statistically significant (p=0.000) decrease in IOP. Retinal redetachment found in 13 (16.5%) cases during follow up period.

Conclusion:

Passive removal of silicone oil with 23 G suture less vitrectomy system is safe and effective in terms of less per operative and post operative complications. In this simple technique, there is less tissue trauma and little time consumed so it provides more comfort to patients and surgeons as well.

Glaucoma management after vitreoretinal surgeries

PURPOSE OF REVIEW

The surgical management of retinal disorders, including scleral buckling procedures, pars plana vitrectomy, and intravitreal injections of gas or silicone oil, can lead to short-term elevations in intraocular pressure (IOP) and ultimately long-term glaucomatous damage if not treated in a timely manner. Glaucoma in these cases is commonly refractory to conventional therapies. This review highlights the treatment strategies for glaucoma in eyes that have previously undergone vitreoretinal surgery.

RECENT FINDINGS

Although medical therapy is often used initially to control a temporary rise in IOP, laser and surgical therapy may be required to treat sustained IOP elevation and subsequent glaucomatous damage in eyes that have undergone intraocular surgery for retinal disorders. Glaucoma drainage devices are an important treatment modality, particularly when there is high risk of failure with filtering surgery.

SUMMARY

Previous vitreoretinal surgery is a known risk factor for the development of glaucoma. Treatment is usually initiated with medical therapy, however, surgical intervention is frequently required to control IOP and prevent progressive glaucomatous damage in patients with refractory glaucoma.

Long-term Follow-up of a Case of Gold Shunt Surgery for Refractory Silicone Oil-induced Glaucoma

Purpose:

To report the first case of gold shunt surgery for treatment of silicone oil–induced refractory glaucoma in a tertiary care academic center, with 5-year follow-up.

Design:

The study design is a case report.

Participants:

The participant was a patient who underwent gold shunt surgery.

Methods:

Institutional Research Ethics Board approval for the study was obtained. A diabetic patient was referred for refractory glaucoma with a history of proliferative diabetic retinal detachment, and surgery with silicone oil. She was uncontrolled on maximal medical therapy and following informed consent, gold shunt surgery was performed. Ocular outcomes and number of medications were reviewed over a 5-year period.

Results:

Following uncomplicated surgery, intraocular pressure was reduced from 41 to 14 mm Hg, and the number of medications was reduced from 4 to 1. Glaucomatous optic neuropathy remained stable.

Conclusions:

Gold shunt surgery in this challenging case of silicone oil refractory glaucoma provided long-term intraocular pressure control and reduced need for medication over a 5-year period.

Apoptosis Factors of Lens Epithelial Cells Responsible for Cataractogenesis in Vitrectomized Eyes with Silicone Oil Tamponade

Background

The aim of this study was to determine the expression of apoptotic factors Bax, Bcl-2, and Caspase-3 in lens epithelial cells (LECs) from cataracts secondary to pars plana vitrectomy with silicone oil (SO) tamponade. We also investigated the impact of SO emulsification on the expression of apoptotic factors.

Material/Methods

Anterior capsulotomy specimens of 20 eyes in 20 patients with cataract secondary to SO tamponade (Group 2), were collected. Another 20 eyes of 20 patients with age-related cataract (Group 1) were recruited as controls. The anterior capsule specimens were obtained from the patients during cataract surgery, frozen and later analyzed with respect to immunohistochemical stains of Bax, Bcl-2, and Caspase-3 using a confocal microscope.

Results

Age, sex, and laterality did not show any difference between the 2 groups. There was a greater increase in Bax and Caspase-3 expression in LEC in Group 2 than in Group 1 (P_Bax<0.0001, P_Caspase-3<0.0001). The Bcl-2 expression decreased in Group 2, although the difference was not significant (P=0.616). The changes of apoptosis factors are not associated to SO emulsification (P_Bax=0.354, P_Bcl-2=0.728, P_Caspase-3=0.939).

Conclusions

The caspase-3-dependent apoptosis of LECs increased in complicated cataract patients with SO endotamponade. The Bax played a critical role in regulating apoptosis of LECs in vitrectomized eyes with SO tamponade. The SO emulsification had no significant impact on the expression of apoptosis factors.

Glaucoma drainage device surgery after vitreoretinal surgery: incidence and risk factors

PURPOSE

The initial success of vitreoretinal surgery can be annihilated by an acceleration of preexisting glaucoma or the development of secondary glaucoma. Aim of this study was to determine the incidence of and risk factors for medically uncontrollable glaucoma after vitreoretinal surgery.

METHODS

Case-control study amongst patients who underwent vitreoretinal surgery at the University Medical Center Groningen between 1991 and 2011 (in total 14,942 interventions). Cases were all patients who received a glaucoma drainage device after vitreoretinal surgery. Controls were a subset of the patients who underwent vitreoretinal surgery without a subsequent drainage device. Cases and controls were matched (three controls per case) with regard to the year of the (first) vitreoretinal intervention. The incidence rate was calculated from the number of cases and the number of person-years corresponding to all vitreoretinal interventions performed in the study period. Risk factors were analysed with logistic regression.

RESULTS

Ninety-five cases were identified after a follow-up of 101,961 person-years (one per 1000 person-years). Cases were younger (p = 0.017), were more often men (p = 0.035), underwent more interventions (p < 0.001) or were treated with silicone oil (p = 0.021), had a higher intra-ocular pressure 1 week after the intervention (p < 0.001) and had more often a history of glaucoma or ocular hypertension (p < 0.001).

CONCLUSION

Glaucoma after vitreoretinal surgery that requires a glaucoma drainage device is not very common and patients who need a device differ from those who do not. This gives the opportunity to monitor certain subgroups more closely.

Aqueous misdirection following pars plana vitrectomy and silicone oil injection

Purpose

To report a retrospective series of seven phakic eyes of seven patients suffering from a malignant glaucoma-like syndrome following pars plana vitrectomy and silicone oil (SO) injection.

Materials and methods

Seven eyes with retinal detachment treated with pars plana vitrectomy with or without scleral buckling with SO tamponade. This was followed by cataract extraction to manage the elevated intraocular pressure (IOP).

Results

This was a retrospective review of seven cases that received pars plana vitrectomy and SO with or without scleral buckling for different causes of retinal detachment (three were rhegmatogenous and four were tractional). After a period ranging from 1 week to 1 month, they presented with malignant glaucoma-like manifestations; high IOP, shallow axial anterior chamber, and remarkable decrease of visual acuity. Atropine eye drops and anti-glaucoma medical treatment (topical and systemic) had been tried but failed to improve the condition. Dramatic decrease of IOP and deepening of the axial anterior chamber was observed in all cases in the first postoperative day after phacoemulsification and posterior chamber foldable intraocular lens implantation with posterior capsulotomy.

Conclusion

Aqueous misdirection syndrome may be observed following pars plana vitrectomy and SO tamponade. This must be differentiated from other causes of post vitrectomy glaucoma. Cataract extraction with posterior capsulotomy controls the condition.