Evaluation of corneal endothelial cell damage after vitreoretinal surgery: comparison of different endotamponades

Effect of the Presence of Silicone Oil in the Anterior Chamber After Complicated Retinal Detachment Surgery on Corneal Morphology by In Vivo Confocal Microscopy

PURPOSE

This study evaluated the corneal endothelium, stromal keratocytes, subbasal nerve number and density in patients with silicone oil transferred to the anterior camera after pseudophakic complicated retinal detachment surgery by in vivo laser scanning confocal microscopy (IVLSCM).

METHODS

Sequential measurements were made by IVLSCM between 3-6 months after surgery in two groups of patients: a) with silicon oil migration (Group 1) and without silicone oil migration (Group 2).

RESULTS

A total of 63 cases (Group 1: 32 and Group 2: 31) were examined. The mean ages of patients were 65 ± 12 and 61 ± 11 and M/F ratio was 18/14 and 17/14, respectively. Mean intraocular pressures were 16.60 ± 4.60 and 15.75 ± 5.70 mm Hg, respectively. Changes were detected by IVLSCM mostly on the superior part of the cornea. A significant decrease in endothelial cell density and the number was detected in group 1 (2072 ± 116.2 cells/mm2 vs 2752 ± 512.3 cells/mm2; p < 0.001). Significant increases in posterior keratocyte density and stromal hyperreflective deposits were observed in group 1 (887 ± 45.8 cells/mm2 vs 725 ± 65.8 cells/mm2; p < 0.001). A significant negative correlation was observed between the size of stromal deposits and endothelial cell density (r=-0.758; p < 0.001). The number and density of corneal subbasal nerves were significantly lower in group 1 (1.8 ± 0.8 and 4.8 ± 1.2 vs 420 ± 101 and 701 ± 112 µm/square; p < 0.001).

CONCLUSION

IVLSCM is a useful tool for the early detection of corneal abnormalities caused by silicone oil injection. This study verified silicone oil's detrimental effect on the corneal endothelium and revealed stromal changes in the anterior chamber, which we believe can be also been associated with the presence of silicone oil.

Clinical Application of Foldable Capsular Vitreous Bodies in the Treatment of Severe Ocular Trauma and Silicone Oil Dependent Eyes

Purpose

This study aimed to assess the application of a foldable capsular vitreous body (FCVB) in the treatment of severe ocular trauma and silicone oil (SO) dependent eyes.

Methods

A retrospective analysis was performed on the clinical application of FCVB in the treatment of severe ocular trauma and SO dependent eyes. The results of best-corrected visual acuity and intraocular pressure (IOP) evaluation, B-scan ultrasonography or color Doppler ultrasonography, ultrasound biomicroscopy, and anterior segment photography were recorded during follow-up. A paired t-test was used to compare the difference in IOP before and after FCVB implantation.

Results

Seven eyes of seven patients were included in the 6-month follow-up. In all cases, B-scan ultrasonography and ultrasound biomicroscopy showed that FCVB adapted closely to the globe wall and ciliary body, thus supporting the retina. Visual acuity did not improve, except in one case from LP to HM. The mean ± SD IOP was 8.5 ± 1.90 mm·Hg prior to FCVB implantation and 10.43 ± 0.98 mm·Hg after implantation, with no significant difference between these measurements (P=0.095). Five of the seven patients developed differing degrees of corneal opacity and keratopathy.

Conclusions

FCVB implantation may be a safe and effective method for the treatment of severe ocular trauma and SO dependent eyes. However, FCVB cannot prevent the phthisis of the traumatic eyes. In addition, corneal opacity and keratopathy are potentially serious complications after surgery. Appropriate case selection and proper surgical timing are required for further investigation.

Retinal and Corneal Changes Associated with Intraocular Silicone Oil Tamponade

Silicone oils (SO) are used as long-term intraocular tamponades and have an irreplaceable role in vitreoretinal surgery. They can, however, be associated with multiple and potentially severe complications, involving different ocular tissues, in particular retina and cornea. Recent advances in ophthalmic imaging have allowed the precise characterization of retinal and corneal microstructural changes, at a subclinical level. This detailed analysis of SO-related retinal and corneal changes has improved our understanding of their pathogenesis and offer the potential for optimized monitoring and management of patients with SO-filled eyes. This review aims to provide clinicians and ophthalmic scientists with an updated and comprehensive overview of the corneal and retinal changes associated with SO tamponade.

Complications in Retinal Surgery: A Review of Corneal Changes Following Vitreoretinal Procedures

Purpose:

The purpose of this article is to discuss the early- and late-onset corneal complications that can occur following vitreoretinal surgery.

Methods:

A systematic review of the literature was conducted using PubMed and Google Scholar databases. Articles detailing the clinical findings and the associations between surgical techniques, irrigating solutions, and microsurgical instruments used for vitreoretinal surgery and postoperative corneal complications were included in this review.

Results:

Vitreoretinal surgery can be associated with corneal complications such as persistent corneal epithelial defects, neurotrophic keratopathy, band keratopathy, ocular surface disruption, and endothelial cell damage. Risk factors for the development of cornea complications after posterior segment surgery include history of uncontrolled diabetes mellitus, aphakia or pseudophakia, disrupted anterior lens capsule integrity, use of irrigating solutions without appropriate buffers, use of contact viewing lenses intraoperatively, intraocular gases or silicone oil after vitrectomy, and prolonged duration of surgery.

Conclusions:

Corneal complications secondary to vitreoretinal surgery are multifactorial, but more commonly arise in diabetic patients, those with preexisting ocular comorbidities, and under certain surgical-related conditions. Special pre-, peri-, and postoperative considerations, with a focus on early identification and management of risk factors, are required to help decrease the incidence of corneal complications.

Return to the Operating Room After Repair of Rhegmatogenous Retinal Detachment

Purpose

To report the rate of all-cause returns to the operating room (OR) after surgery for rhegmatogenous retinal detachment (RRD).

Patients and Methods

This was a retrospective consecutive case series; 1278 eyes underwent RRD repair from 1/1/2014 to 12/31/2016 at a tertiary care center. A total of 507 eyes returned to the OR. Surgical indication, procedure, number of reoperations, and final vision were recorded.

Results

At least one secondary procedure was performed in 24.9% at 6 months, 34.7% at 1 year, and 39.7% as of last follow-up. The most common indications for reoperation were cataract (43.9%) and recurrent RRD (12.8%). Cornea, glaucoma, and oculoplastic issues were rare (each <1.1%). There was no association between final visual outcome and number of reoperations (p > 0.05). SB/PPV had the highest rate of return to OR (p < 0.001) but lowest rate of recurrent RRD (p = 0.007).

Conclusion

To our knowledge, there are no other large studies that examine all-cause returns to the OR after primary RRD repair. This study provides important risk-benefit and prognostic information to patients undergoing RRD repair.

ENDOTHELIAL CELL LOSS AFTER PARS PLANA VITRECTOMY

AIMS

To analyse the changes in endothelial cell density (ECD) after pars plana vitrectomy (PPV) and to identify the factors implicated.

PATIENTS AND METHODS

This was a prospective, consecutive, and non-randomised, case-control study. All 23-gauge vitrectomies were performed by a single surgeon at a tertiary centre. ECD was measured at baseline before surgery and on postoperative Days 30, 90, and 180. The fellow eye was used as the control eye. The primary outcome was a change in ECD after PPV.

RESULTS

Seventeen patients were included in this study. The mean age of the patients was 65 years. The mean ECD count at baseline was 2340 cells/mm2. The median ECD loss in the vitrectomised eye was 3.6 %, 4.0 %, and 4.7 % at Days 30, 90, and 180, respectively, compared to +1.94 %, +0.75 %, +1.01 %, respectively, in the control eye. The relative risk of ECD loss after PPV was 2.48 (C.I. 1.05-5.85, p = 0.0247). The pseudophakic eyes lost more ECD than the phakic eyes, but this was not statistically significant. There were no significant differences in diagnosis, age, surgical time, or tamponade used after surgery.

CONCLUSIONS

Routine pars plana vitrectomy had an impact on the corneal endothelial cells until Day 180 post-op. The phakic status was slightly protective against ECD loss after PPV, although it was not statistically significant. The pathophysiology of corneal cell damage after routine PPV remains unclear. Further studies are required to confirm these findings.

Optimization of Contact Lenses for Corneal Protection During Vitreoretinal Surgery

OBJECTIVES

To optimize parameters of contact lenses (CLs) and evaluate their ability to protect the cornea during vitreoretinal surgery.

METHODS

We compared the protective effects of balanced saline solution, viscoelastic agent, and CLs on rabbit corneas under conditions simulating vitreoretinal surgery. We evaluated CLs of different thicknesses and compared the protective effects of polymethyl methacrylate (PMMA) and gas-permeable fluorosilicone acrylate (XO) lenses on the corneas of rabbits and patients with severe proliferative diabetic retinopathy (PDR). The corneal fluorescein staining score (FSS) was measured to compare the protective effects of CLs.

RESULTS

The FSS was significantly lower in the PMMA group than in the balanced saline solution and viscoelastic agent groups. The thickness of the PMMA lenses had no significant effect on the FSS. The FSS was significantly higher in the PMMA group than in the XO group. In patients with PDR, on day 1 after vitreoretinal surgery, the FSS was significantly higher in the PMMA group than in the XO group, although no significant difference was observed on postoperative day 7.

CONCLUSION

The XO lens offers better corneal protection during noncontact wide-angle vitreoretinal surgery and protects the corneal epithelium more efficiently during vitrectomy in patients with PDR, irrespective of its thickness.

Changing Indications for Corneal Transplantations in Southern Taiwan From 2008 to 2018

OBJECTIVES

To investigate the changing indications for corneal transplantations in southern Taiwan from 2008 to 2018 and compare the results with those of other previous studies.

METHODS

We retrospectively reviewed the records of patients who underwent corneal transplantations from January 2008 to December 2018 at Kaohsiung Veterans General Hospital. The patients' age, sex, indication for corneal transplantation, and the surgical technique were recorded and analyzed.

RESULTS

In total, 336 patients (421 eyes) were included in our study from January 1, 2008, to December 31, 2018. The mean age was 63.6±15.3 years; 371 penetrating keratoplasty (88.1%), 35 deep anterior lamellar keratoplasty (8.3%), and 15 Descemet-stripping automated endothelial keratoplasty (3.6%) were performed. The leading indication for corneal transplantation was regraft (n=103, 24.5%), followed by bullous keratopathy (n=82, 19.5%), corneal scar and opacity (n=79, 18.8%), keratitis (n=59, 14.0%), corneal dystrophy (n=58, 13.8%), other indications (n=26, 6.2%), and keratoconus (n=14, 3.3%).

CONCLUSION

The indications for corneal transplantations changed with time in Taiwan. Regraft was the leading indication, but there was a decreasing trend over time. The proportion of bullous keratopathy increased significantly over the past decade and is the second most common indication, similar to the most developed countries. Both corneal scar and opacity, and keratitis showed a decreasing trend of occurrence compared with a previous study in Taiwan. The proportion of keratoconus remained low, making it the least common indication for corneal transplantation.

Status of corneal endothelial cells in the presence of silicone oil in the anterior chamber

To evaluate corneal endothelium damage with silicone oil (SO) presence in the anterior chamber after pars plana vitrectomy. We investigated the medical records of consecutive 54 eyes of 53 patients undergoing SO removal after pars plana vitrectomy with SO tamponade at Saitama Medical Center, Jichi Medical University, Japan. We recorded SO tamponade retention period, anterior chamber SO with gonioscope, area of SO attachment to the corneal endothelium before SO removal surgery, and the lens status. We then retrospectively investigated the correlation between SO presence in the anterior chamber and the decrease rate of corneal endothelial cell (CEC) density during SO tamponade. The average decrease rate of CEC density was 7.6 (0–38.1) %. The correlation between SO tamponade retention period and decrease rate of CEC density was high (p = 0.0001). However, there was no correlation between anterior chamber SO under gonioscope, SO attaching area, and lens status with the decrease rate of CEC density (p = 0.11, p = 0.93, p = 0.16). No correlation was observed between CEC loss and the existence of anterior chamber SO, although CEC decrease rate was relatively high after a long SO tamponade period. These findings suggest that SO presence in the anterior chamber may not directly injure CEC.

[Specular microscopy findings in active uveitis]

PURPOSE

To study the effect of ocular inflammation in active uveitis on the corneal endothelium.

MATERIALS AND METHODS

This is a prospective cross-sectional study involving 63 eyes of 38 patients with active newly-diagnosed uveitis. Eighty-four eyes of 42 non-uveitic subjects served as a control group. All patients underwent detailed ophthalmic examination, laser flare photometry, and non-contact specular microscopy. Eyes with uveitis had a follow-up visit at one month after initiation of treatment, including laser flare photometry and specular microscopy.

RESULTS

The mean age of the active uveitis patients was 33 (range: 9-67 years) with 21 men (55%) and 17 women (45%). For the uveitis patients at baseline, the mean flare value was 32ph/ms (range: 15-100ph/ms) with flare photometry value ≥50ph/ms in 13 eyes (21%) and<50ph/ms in 50 eyes (79%). At baseline, cell density (CD) of the uveitis patients was similar to CD in control eyes (p꞊0.16). The percent of hexagonality was significantly lower (p<0.0001), and the coefficient of variance (CV) (p<0.0001) and central corneal thickness (CCT) (p<0.0001) were significantly higher than in the control group. After one month, there was a significant decrease in flare photometry values (p<0.0001), with a mean flare value of 14.5ph/ms (range: 4-60ph/ms). In the active uveitis group, the overall results of specular microscopy did not significantly vary between the initial examination and the 1-month examination. For eyes with flare photometry value ≥50ph/ms at baseline, CD and hexagonal cell count significantly increased on the 1-month examination (p꞊0.01 and p꞊0.02 respectively), while CV and CCT decreased significantly at the one-month follow-up visit (p꞊0.007/p꞊0.03 respectively). For eyes with flare photometry value at baseline <50ph/ms, there was no significant differences in specular microscopy results between the initial examination and the 1-month examination.

CONCLUSIONS

In eyes with newly-diagnosed uveitis and active anterior chamber inflammation, specular microscopy shows transient qualitative abnormalities of the corneal endothelium that depend on the severity of the anterior chamber inflammation as measured by the laser flare meter.

Endothelial corneal cell damage after pars plana vitrectomy: analogy of different intraocular tamponade agents

A reduction in the corneal endothelial cells multitude after anterior pole intervention is well established in numerous researches, but there are few articles that follow the impact of vitreoretinal interventions on the cornea, especially when endotamponade agents are used. The assessment of the endothelial corneal cells is needed since it facilitates the personal evaluation of the functional endothelial stock. Specular microscopy investigation offers a scale of the functional strength of the endothelium of cornea, which is vital before all intraocular interventions.

Endotamponade agents are very suitable and important tools in the surgical treatment of retinal detachment, but their use must be differentiated depending on the uniqueness of each patient. This research shows corneal endothelial damages caused by intraocular tamponade agents of different types in the case of pars plana vitrectomy for cases of multitude retinal detachments. The purpose of the research was to determine the changes that appear in the endothelium of the cornea and to deal with the results when different tamponade agents are used in the surgical cure for retinal detachment. Specular endothelial corneal microscopy records were achieved and the modifications of the following parameters revealed corneal implication: mean endothelial cell densities, average cell area, coefficient of variation, hexagonality and corneal center thickness. On the first day and at three months postoperatively, a statistically significant reduction was observed for the CV, MCD, and HEX parameters (p 0.001), but no statistically significant difference of the two endotamponade agents (for MCD, p=0.15; for CV, p=0.63; for HEX, p=0.93) was noticed. AVG parameter had a statistically significant decrease (p 0.001) and there was also a statistically significant difference of the two endotamponade agents (p=0.03), patients with gas tamponade presenting a superior result. On the first day and at three months postoperatively, the corneal center thickness presented a statistically significant increase (p 0.001) and there was a statistically significant difference between the two endotamponade agents (p=0.03), patients with gas endotamponade presenting a superior result. In conclusion, using the intraocular tamponade agents helps reestablish the functional-anatomical recovery of the retina after surgery, but their special indication must be well-established for each case of retinal detachment.

Current Situation and Challenges in Vitreous Substitutes

Vitreo-retinal disorders constitute a significant portion of treatable ocular diseases. These pathologies often require vitreo-retinal surgery and, as a consequence, the use of vitreous substitutes. Nowadays, the vitreous substitutes that are used in clinical practice are mainly divided into gases (air, SF₆ , C₂ F₆ , C₃ F₈ ) and liquids (perfluorocarbon liquids, silicone oils, and heavy silicone oils). There are specific advantages and drawbacks to each of these, which determine their clinical indications. However, developing the ideal biomaterial for vitreous substitution continues to be one of the most important challenges in ophthalmology, and a multidisciplinary approach is required. In this sense, recent research has focused on the development of biocompatible, biodegradable, and injectable hydrogels (natural, synthetic, and smart), which also act as medium and long-term internal tamponade agents. This comprehensive review aims to cover the main characteristics and indications for use of the extensive range of vitreous substitutes that are currently used in clinical practice, before going on to describe the hydrogels that have been developed recently and which have emerged as promising biomaterials for vitreous substitution.

Long-term outcome of scleral-fixated intraocular lens implantation without conjunctival peritomies and sclerotomy in ocular trauma patients

Background

To investigate the long-term outcomes and complications of scleral-fixated intraocular lens (SFIOL) implantation without conjunctival peritomies and sclerotomy in patients with a history of ocular trauma with inadequate capsular support during primary pars plana vitrectomy or silicone oil removal.

Methods

Records of ocular trauma patients who underwent implantation of SFIOL without conjunctival peritomies and sclerotomy during primary pars plana vitrectomy or silicone oil removal.

Results

Sixty-nine eyes of 69 patients were included in this study. The median follow-up period was 34 months (range, 6–99 months). The average patient age at the time of surgery was 44 years old (range, 4–80 years). At the end of follow-up, the preoperative mean of best corrected visual acuity (BCVA) was 0.79 ± 0.86 log of the minimum angle of resolution (logMAR), which improved 0.20 ± 0.26 logMAR postoperatively (P = 0.01). BCVA improved or remained unchanged in 64 eyes (92.8%), VA decreased two lines in five eyes (7.2%). Early postoperative complications included transient corneal edema in seven eyes (10.1%), minor vitreous hemorrhage in four eyes (5.8%), transient elevated intraocular pressure (IOP) in one eye (1.4%), and hypotony in three eyes (4.3%). Late postoperative complications included persistent elevated IOP in five eyes (7.2%), epiretinal membrane formation in three eyes (4.3%), and cystoid macular edema noted in one eye (1.4%).

Conclusions

Use of a scleral-fixated intraocular lens implantation without conjunctival peritomies and sclerotomy in ocular trauma patients during either primary pars plana vitrectomy or second silicone oil removal is a valuable approach for the management of traumatic aphakia in the absence of capsular support.

Electronic supplementary material

The online version of this article (10.1186/s12886-019-1172-4) contains supplementary material, which is available to authorized users.

Chandelier-assisted scleral buckling using wide angle viewing contact lens for pseudophakic retinal detachment repair

AIM

To evaluate a modified technique for scleral buckling (SB) in pseudophakic retinal detachment (RD).

METHODS

A retrospective non-comparative study included 21 consecutive eyes with uncomplicated pseudophakic RD that was repaired by chandelier assisted SB using wide angle viewing (WAV) contact lens. Segmental tire alone was used in 5 eyes (23.81%), and combined with encircling band in 7 eyes (33.33%). Radial sponge alone was used in 3 eyes (14.29%) and combined with encircling band in 6 eyes (28.57%).

RESULTS

Primary success rate was (90.48%). External drainage of subretinal fluid was performed in 8 eyes (38.1%). Intraoperative complications included vitreous prolapse at chandelier sclerotomy site in 4 eyes (19.05%) and localized subretinal hemorrhage at drainage site in one eye (4.76%). No case of intraocular lens (IOL) displacement, retinal incarceration or iatrogenic retinal tear was detected. Postoperative complications included choroidal detachment in one eye (4.76%), elevated intraocular pressure in 2 eyes (9.52%), epiretinal membrane formation in one eye (4.76%) and proliferative vitreoretinopathy in 3 eyes (14.29%). Mean postoperative corrected distance visual acuity was 0.7±0.3 logMAR units.

CONCLUSION

Chandelier-assisted SB using WAV contact lens is a reliable technique for repairing selected cases of simple pseudophakic RD.

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

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

Complications Associated with the Use of Expandable Gases in Vitrectomy

Intraocular gases have been used in vitreoretinal surgery for over 40 years. The aim of this study was to review the complications related to the use of expandable gases in vitrectomy and their management. A PubMed, Cochrane Library, and Embase search was conducted using the terms "intraocular gas" and "vitrectomy for retinal detachment." Of the articles retrieved by this method, all publications in English and abstracts of non-English publications were reviewed. Intraocular pressure elevation was reported in up to 58.9% patients after vitrectomy with expandable gas administration for retinal detachment. Vitreoretinal surgery is known to induce cataract development. With that, cataract progression is associated with lens exposure to intraocular gas, the duration of such exposure, patient's age, and the magnitude of vitreous removal. With intraocular gas, the posterior surface of the lens becomes a strongly refractive factor, resulting in high myopia and temporary vision impairment. Other complications related to the use of expandable gases include anterior chamber and subconjunctival gas displacement. Single reports on subretinal and cranial gas migration were published. In vitrectomy for uncomplicated retinal detachments, attempts to shift from expandable gases towards air are observed. Nevertheless, gas tamponade remains a reasonable choice for patients suffering from retinal detachment.

Change in central corneal thickness, corneal endothelial cell density, anterior chamber depth and axial length after repair of rhegmatogenous retinal detachment

Objective

To compare the effects of Pars Plana Vitrectomy (PPV) and Scleral Buckling (SB) with reference to Central Corneal Thickness (CCT), Corneal Endothelial-Cell Density (CED), Anterior Chamber Depth (ACD) and Axial Length (AL) in repair of Rhegmatogenous Retinal Detachment (RRD).

Methods

This comparative cross sectional analytical study was conducted at Armed Forces Institute of Ophthalmology (AFIO), Rawalpindi from July 2013 to July 2015. A total of 69 eyes of 69 patients which underwent repair of RRD by either PPV or SB were analyzed to compare mean change in CCT, CED, ACD and AL between two groups.

Results

Mean age of patients was 56.23±5.22 years. Mean pre-operative CCT, CED, ACD and AL in PPV group was 533.06±13.28µm, 2231.67±164.57Cells/mm², 3.37±0.18mm and 23.66±0.76mm respectively. Mean post-operative CCT, CED, ACD and AL in PPV group was 534.81±11.83µm, 2037.19±167.83 Cells/mm², 3.24±0.13mm and 23.88±0.80mm respectively. Change in CED, ACD and AL from pre-operative value after PPV was statistically significant (p<0.001). Mean pre-operative CCT, CED, ACD and AL in SB group was 530.73±12.59 µm, 2161.79±161.96 Cells/mm², 3.343±0.14mm and 23.67±0.82mm respectively. Mean post-operative CCT, CED, ACD and AL in SB group was 532.76±7.74 µm, 2158.27±156.58 Cells/mm², 3.24±0.10mmand 25.71±0.86mm respectively. Change in ACD and AL from pre-operative value after SB was statistically significant (p<0.001). Mean change of CED, ACD and AL between two groups was also statistically significant (p<0.001).

Conclusion

Rhegmatogenous retinal detachment repair causes ocular changes, with significantly more decrease in corneal endothelial cell density after pars plana vitrectomy, and more increase in anterior chamber depth and axial length after scleral buckling.