[Use of silicone oil in vitreal hemorrhage complicating proliferated diabetic retinopathy]

A pilot study of viscoelastic agent to prevent recurrent vitreous hemorrhage after vitrectomy for proliferative diabetic retinopathy

BACKGROUND

To evaluate the possibilty of preventing recurrent vitreous hemorrhage (RVH) after vitrectomy in proliferative diabetic retinopathy (PDR) patients with unabsorbed vitreous hemorrhage (VH) by intravitreal injection of viscoelastic agent (VA) at the end of the surgery and compared its effect with triamcinolone acetonide (TA).

METHODS

This was a pilot prospective, observational study. PDR patients with VH who underwent vitrectomy were assigned to 3 groups according to the tamponade applicated at the end of the surgery, including VA group (intravitreally injected 1 ml VA if the retina was prone to bleed during the operation), TA group (intravitreally injected 2 mg TA when there was much exudates), or balanced salt solution (BSS) group (no tamponade). Then postoperative follow-up was performed routinely until 6 months after surgery. The primary outcome was the incidence of RVH, secondary outcome were the best-corrected visual acuity (BCVA) and introcular pressure (IOP). Cataract formation and other complication were also assessed.

RESULTS

A total of 68 eyes, from 68 patients, were included. 18,18,32 eyes were enrolled in the VA group, TA group and BSS group, respectively. The integral incidence of RVH after vitrectomy was 5.6%, 5.6% and 12.5% respectively (P = 0.602). There was no early RVH in VA or TA group, whereas 3 early RVHs were identified in BSS group, however there was no significant difference (P = 0.171). Every group had one late RVH case. In all groups, final BCVA showed significant improvement compared to baseline. BCVA at any postoperative visit showed no significant differences among 3 groups. Mean IOP was higher 1 week after surgery in VA group compared with the other groups; however, in other times the differences were not significant. No cataract formation and other complication was noted in 3 groups.

CONCLUSION

Intravitreal injection of VA or TA at the end of vitrectomy for PDR patients with unabsorbed VH tend to reduce the incidence of early RVH after vitrectomy similarly. As VA was preferred to applicate in the eyes that were prone to bleed, intravitreal injection of VA at the end of vitrectomy might be a promising method for preventing RVH in PDR patients.

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.

Silicone oil removal: post-operative complications

PURPOSE

To describe the characteristics, outcomes and complications of eyes after silicone oil removal.

METHODS

Retrospective case series of eyes that underwent oil removal between 2012 and 2016 at The Institute of Ophthalmology and Visual Science. Visual acuity (VA), intraocular pressure (IOP) and rates of retinal re-detachment, hypotony, ocular hypertension, corneal decompensation, cystoid macular edema (CME) and cataract progression were evaluated.

RESULTS

Totally, 101 eyes of 99 patients (65% male, average age 47.2 years) were identified. Oil tamponade had been used for retinal detachment (RD) repair in all eyes; 15 eyes had also undergone an open globe repair previously. The most common vitreous substitutes used after oil removal were balanced salt solution (BSS) and air in 90% of eyes. The average time of oil tamponade before removal was 9.46 months. The average logMAR VA before oil removal was 1.7 which improved to an average of 1.4 post-operatively. The average IOP pre-operatively was 16.1 mm Hg, which decreased to an average of 14.8 mm Hg post-operatively. Complications after oil removal, included retinal re-detachment (6.9%), hypotony (7.9%), ocular hypertension (12.9%), corneal decompensation (9.9%), CME (2%) and cataract progression (68%).

CONCLUSION

This study showed an overall improvement in VA and decrease in IOP after oil removal. Cataract progression was the most common complication.

Predictors and Outcomes of Vitrectomy and Silicone Oil Injection in Advanced Diabetic Retinopathy

PURPOSE

To evaluate visual and anatomical results and identify factors that influence vitrectomy and silicone oil (SO) injection outcomes in proliferative diabetic retinopathy (PDR).

METHODS

This retrospective study included 236 eyes with PDR that were undergoing vitrectomy and SO injection with >3-month follow-up. The primary outcomes were final best-corrected visual acuity (BCVA) and retinal attachment rate.

RESULTS

At the final visit (mean, 88 ± 58 weeks), complete, partial, and no retinal attachment were observed in 86.9%, 10.6%, and 2.5% of patients, respectively. A total of 155 eyes had experienced SO removal, while 81 had SO in place. The mean initial BCVA was 1.9 ± 0.7 logarithm of the minimum angle of resolution (logMAR) and significantly improved to 1.7 ± 0.8 logMAR (p = 0.001). Initial macular detachment (adjusted odds ratio [AOR], 0.25), development of iatrogenic break (AOR, 0.25), and use of heavy SO (AOR, 0.13) were independently associated with a lower risk of final retinal attachment, and SO removal was associated with a higher incidence (AOR, 7.55). Better baseline BCVA was associated with a higher risk of final BCVA ≥20 / 200.

CONCLUSIONS

Despite an encouraging outcome based on anatomical data in advanced PDR treated with vitrectomy and SO, the functional prognosis was not satisfying for patients. Eyes with better vision at baseline had a more favorable prognosis, whereas eyes with initial macular detachment, intraoperative iatrogenic break, or heavy SO showed more unfavorable outcomes. In selected cases, extending the time of SO use did not worsen the prognosis.

[Long-term use of silicone oil: indications and tolerance]

PURPOSE

The aim of this study was to analyze the indications and the effect of permanently maintaining silicone oil in the treatment of certain cases of vitreoretinal pathology.

PATIENTS AND METHODS

Twenty-seven cases seen from January 2002 to December 2008 were retrospectively studied. Silicone oil was kept in the eyes for more than 2years. The surgical file was analyzed in all cases. The evaluation criteria were ocular pressure, emulsification, cataract, corneal dystrophy, and the functional response of the retina and optic nerve. Ultrasound echography (12 MHz), magnetic resonance imaging, and electrophysiological explorations (visual evoked potential and electroretinography) were performed.

RESULTS

Twenty-seven eyes of 27 patients were included in this study. The main reasons for maintaining long-term silicone oil are recurrent vitreous hemorrhage, retinal detachment with severe proliferative vitreoretinopathy, and penetrating injury. The patients were distributed into two groups: group 1 included patients with both functional and anatomic failure, group 2 patients had achieved ambulatory vision. Follow-up ranged from 27 to 72months. Cataract incidence was approximately 91% in group 2. Emulsification was noted without high pressure in 50% of the cases in group 1. High pressure averaged 31.8% in group 2. Keratopathy was observed in 9% of the cases in group 2. Intraorbital migration of silicone oil was found in one case. The visual field was improved in 77% of the cases in group 2.

CONCLUSION

This study provided interesting insights into certain clinical situations in which silicone oil has to be maintained permanently. The complications stem not only from the presence of silicone oil, but also from the preoperative status of the eye and the vitreoretinal surgery.