Trypan blue injection into the capsular bag during phacoemulsification: Initial postoperative posterior capsule opacification results

Recurrent Posterior Capsular Opacification in Adults: A Case Report and an Overview of Literature

Posterior capsular opacification (PCO), also known as "secondary cataract", is a common complication following cataract surgery that can significantly impair visual acuity. The incidence of PCO varies widely in the literature, influenced by intraocular lens (IOL) type and patient risk factors. Neodymium-doped yttrium-aluminum-garnet (YAG) laser posterior capsulotomy is the standard treatment for PCO-related visual impairment. Recurrence of PCO after initial treatment with YAG capsulotomy, though more common in children, is rare in adults. Its underlying pathophysiological mechanisms are similar to that of primary PCO, which includes proliferation, migration, and/or clustering of lens epithelial cells (LECs), with subsequent reclosure of the posterior aperture. Potential risk factors for PCO recurrence that have been speculated through a comprehensive search of the current literature include younger age, female sex, high myopia, diabetes, vitrectomized status, uveitis, low-diopter IOLs, and certain IOL types with higher water content. We present a case of recurrent PCO in a highly myopic 48-year-old male following cataract surgery and implantable collamer lens (ICL) explantation who received a hydrophobic acrylic lens with 4% water content. Surgical techniques that may reduce recurrent PCO occurrence and appropriate postoperative care are emphasized to assist surgeons in their approach to patients at high-risk for this complication.

Comparative histomorphologic study of basement membrane side staining and additional epithelial side staining of the anterior lens capsule with Trypan Blue

PURPOSE

To compare the histomorphologic changes on the anterior lens capsule by both epithelial and basement membrane side staining to those of only basement membrane side staining of the anterior lens capsule with Trypan Blue (TB).

METHODS

A cross-sectional study was done on 72 samples from patients who underwent cataract surgery between April 2021 and September 2022. After capsulorhexis of the TB-stained capsule, it was made into two halves externally and one half labeled as controls (sample A). The other half was immediately stained further with TB on the epithelial side and was taken as cases (sample B). Samples were analyzed for lens epithelial cells and basement membrane changes.

RESULTS

The loss of intactness of lens epithelial cells, partial or complete detachment of lens epithelial cells, degeneration of lens epithelial cells, and basement edema were significantly higher in cases compared to controls, whereas intactness of the basement membrane did not show any statistical significance between the two groups. There was a statistically significant decrease in cell density in cases compared to controls.

CONCLUSION

Staining the epithelial side of the capsular bag with TB is more detrimental to lens epithelial cells and paves the way for a further study of staining the capsular bag before intra-ocular lens implantation to reduce the incidence of posterior capsule opacification.

Lens Epithelial Cell Removal in Routine Phacoemulsification: Is It Worth the Bother?

PURPOSE

To review the literature on crystalline lens epithelial cell (LEC) removal in routine phacoemulsification and determine whether it should be incorporated as part of a surgeon's standard technique.

DESIGN

Perspective.

METHODS

Expert commentary with video demonstrations on techniques of removal of LECs and associated potential complications. Discussion incorporates the importance of LEC removal, a review of techniques to prevent posterior capsular opacification (PCO), and the effects of intraocular lens design on LEC proliferation and PCO.

RESULTS

The evidence suggests that LEC removal should be routinely performed as it can be carried out safely and with considerable short- and long-term benefits for patients. With effective cleanup, there is reduced anterior capsule opacification, fibrosis, and decentration of the capsular bag as well as reduced rates of posterior capsular opacification. Techniques for removal are easy to learn, with very low complication rates, and can reduce the risk of the long-term need for technically complex procedures such as intraocular lens explantation.

CONCLUSIONS

LEC removal from both the anterior and posterior capsule is part of a continuous, incremental improvement of cataract surgery and should be introduced to ophthalmology trainees during their formative years as part of their regular cataract surgery armamentarium.

The effects of trypan blue use on the corneal endothelium during cataract surgery in patients with pseudoexfoliation syndrome (PEX)

PURPOSE

In the present clinical study, it was aimed to investigate the possible effects of Trypan blue (TB) use on the corneal endothelium during cataract surgery in eyes with pseudoexfoliation syndrome (PEX) during a three-month follow-up period using the contralateral eye control design.

METHODS

This prospective, randomised controlled, individual cohort study included 92 eyes of 46 patients with bilateral PEX and cataracts. While 1% TB was applied to one eye of the patients before capsulorhexis (study group), it was not applied to the other eye (control group). Both groups were compared preoperatively and postoperatively in terms of endothelial cell density (ECD), endothelial cell loss (%), pleomorphism, polymegathism and central corneal thickness (CCT) using specular microscopy.

RESULTS

Preoperative corneal ECD was measured as 2362.56 ± 253.27 in the study group, 2380.84 ± 220.54 in the control group, and 2145.58 ± 221.71 in the study group and 2184.97 ± 200.94 cells/mm² in the control group in the postoperative 3rd-month follow-up (p = 0.71 and = 0.37, respectively). In addition, there were no significant differences between the two groups in terms of the percentage of hexagonal cells, coefficient of variation (CV), and CCT both preoperatively and postoperatively 3 months later (p = 0.78, =0.39, =0.95 preoperatively and p = 0.31, =0.26, =0.83 postoperatively, respectively).

CONCLUSION

This study demonstrated that the injection of 1% TB into the anterior chamber for staining the anterior capsule during cataract surgery did not cause significant corneal endothelial changes at postoperative 3^rd months, despite the increased fragility of corneal endothelial cells in patients with PEX.

Research Progress of Drug Prophylaxis for Lens Capsule Opacification after Cataract Surgery

Phacoemulsification combined with intraocular lens (IOL) implantation is the international standard operation procedure for cataract and has been generalized worldwide. However, lens capsule opacification, one of the common complications after cataract surgery, impacts the recovery of patients' visual function to a large extent. Lens capsule opacification has two types, anterior capsule opacification (ACO) and posterior capsule opacification (PCO), according to the location. There is not an accepted approach to treat ACO. Nd : YAG laser capsulotomy, the common treatment of PCO, can effectively improve the vision, but may cause a series of complications and is inappropriate for children who are too young to cooperate with this treatment. It is generally known that the responses of lens epithelial cells (LECs) after cataract surgery, including cell proliferation, migration, and epithelial-mesenchymal transition (EMT), play a key role in the pathogenesis of lens capsule opacification. Scholars found that substantial drugs can reduce the occurrence of lens capsule opacification by inhibiting, clearing, or killing LECs, and made great efforts as well as innovations on the exploration of drug species or modes of administration. This article is a systematic interpretation and elaboration about how to prevent lens capsule opacification after cataract surgery via different drugs.

Rotation versus non-rotation of intraocular lens for prevention of posterior capsular opacification

Purpose:

To study the effect of rotation of intraocular lens (IOL) on posterior capsular opacification (PCO) in eyes with phacoemulsification.

Methods:

This was a prospective, comparative, randomized case series. One eye of each patient was randomized to one of two groups. The 360-degree rotation of IOL was carried out after its placement in the capsular bag (rotation group). The control group had no rotation of IOL. PCO was analyzed by an independent observer on EPCO computer analysis system at 6, 12, 24, and 36 months.

Results:

The study included 50 patients (100 eyes) with senile cataracts scheduled for phacoemulsification and IOL implantation. The median age in 2 groups was 66 years. 25% quartile age in both the group was 62 years (P = 0.06). There were 30 males, and 20 females. The median PCO score at 6, 12 and 24 months was significantly low in the rotation group (0.15, 0.13, 0.22) compared to the control group (0.22, 0.23, 0.25). There was no significant difference in PCO score between the two groups from 24-36 months. The median PCO score at 36 months was 0.2 in both the groups. At the end of three years, 4 eyes (8%) in the rotation group, and 10 eyes (20%) in the control group needed Nd:YAG capsulotomy (P = 0.04).

Conclusion:

Rotation of IOL in the capsular bag decreases PCO and Nd:YAG capsulotomy rate.

Determination of trypan blue efficacy in the mitigation of ex vivo canine PCO formation

PURPOSE

To determine whether trypan blue (TB) reduces canine lens epithelial cell (LEC) or corneal endothelial cell (CEC) viability in vitro; if cell death is noted, to subsequently evaluate the molecular mechanism.

METHODS

Cellular viability was determined using a lactate dehydrogenase (LDH) assay. In TB-treated LECs, caspase 3/7 activity was assessed to evaluate apoptosis; autophagy was evaluated using immunoblotting against LC3 and p62. To evaluate the effects of TB on ex vivo posterior capsule opacification (PCO), following mock cataract surgery, lens capsules were treated with TB and subsequently maintained in culture to determine LEC migration and proliferation.

RESULTS

Following acute exposure, TB did not significantly reduce LEC or CEC viability at any of the concentrations tested. Increased caspase 3/7 activity was found in LEC cultures treated with TB for an extended period of time; no change in LC3 or p62 expression was noted. Ex vivo PCO formation was not significantly altered by TB treatment.

CONCLUSIONS

Acute exposure to TB did not reduce LEC or CEC viability, and only longer exposure to TB was able to initiate apoptosis. Treatment with intraocular TB at the time of cataract surgery is likely safe to the CECs but will not prevent PCO formation.

Effect of intraoperative trypan blue on lens epithelial cells - Histomorphological analysis

Introduction

Trypan Blue is an acid azo dye commonly used as a stain to distinguish viable from non-viable cells. It is a vital stain used intra operatively during cataract surgery to stain the external surface of the anterior lens capsule for better visualization.

Aim

To analyze the histomorphological effects of trypan blue on Lens Epithelial cells and the Basement Membrane on direct exposure by staining the internal surface of the anterior lens capsule during Small Incision Cataract Surgery.

Methods

Analytical cross sectional case control study. Anterior capsule specimens of 14 Patients undergoing small incision cataract surgery at Department of Ophthalmology, Govt Medical College Hospital, Thrissur were studied. Two specimens of anterior capsule taken from the same eye form the case and control. Control specimen (sample A) was removed first, after the routine external staining with trypan blue 0.06% (w/v) for 10 seconds. The stain was washed off by balanced salt solution in every case. Then trypan blue was injected under the remaining anterior capsule and case (Test) specimen (sample B) was obtained after direct contact of trypan blue to the internal surface (lens epithelial cells) for 1 minute. Histomorphological (qualitative and quantitative) examination of both specimens done.

Results

Qualitative data analysis was done by EPI INFO software.v.7. Intactness of LECs throughout the length was statistically significant in Sample A (p = 0.000027). Partial and complete detachment of Lens Epithelial Cells, degeneration, and nuclear smudging were significantly higher in Sample B. Qualitative analysis of the basement membrane showed significant edema of the basement membrane in sample B. Basement membrane splitting observed in sample B was not statistically significant. Quantitative data analyzed using independent t test. There was a statistically significant decrease in cell density in sample B with p value less than 0.05.

Discussion

Our study demonstrated that direct staining of the internal surface of anterior capsule with trypan blue affected LECs and the basement membrane. There were reduction in cell density, irreversible degeneration of Lens Epithelial Cells and basement membrane edema. Hence treating the internal surface of capsular bag with trypan blue may reduce incidence of Posterior capsular opacification.

Safety of Trypan Blue Capsule Staining to Corneal Endothelium in Patients with Diabetic Retinopathy

Purpose

To study the potential corneal endothelial cell toxicity of trypan blue (TB) when used for phacoemulsification to stain the anterior capsule in patients with diabetic retinopathy.

Methods

This was a single-center, prospective, randomized, individual cohort study. One eye in each patient with diabetic retinopathy underwent phacoemulsification without trypan blue capsule staining (control eye), while the other eye underwent phacoemulsification with trypan blue capsule staining (study eye). Both eyes underwent intraocular lens implantation. Preoperative and four-week postoperative quantitative and qualitative morphometric endothelial cell analyses of the cornea were performed using noncontact specular microscopy.

Results

There were no significant differences in endothelial cell density (mean ± SD for the study group: 2506.74 ± 413.99 cells/mm²; mean ± SD for the control eyes: 2466.34 ± 369.12 cells/mm²; P=0.316) or endothelial cell density (CD) loss% (mean CD loss% was 7.23 ± 13.31 for the study eyes and 9.94 ± 9.36 for the control eyes; P=0.157) four weeks after the operation. Additionally, no significant differences were seen in the percentage of hexagonal cells, coefficient of variation, or corneal thickness between the two groups preoperatively and 4 weeks postoperatively.

Conclusions

Direct administration of trypan blue into the anterior chamber for staining of the anterior capsule during cataract surgery did not result in any significant corneal endothelial changes on specular microscopy in patients with severe nonproliferative diabetic retinopathy or high-risk proliferative diabetic retinopathy at 4 weeks postoperatively. This trial is registered with NCT03755752.

Long-term results of trypan blue dye irrigation in the capsular bag to prevent posterior capsule opacification: A randomized trial

Purpose:

To study the effect of capsular bag irrigation of trypan blue dye (0.06%) on posterior capsular opacification (PCO) in eyes undergoing phacoemulsification.

Methods:

This was a randomized, trial conducted at a tertiary eye care center in central India. The study included 50 patients (100 eyes) with senile cataracts who were scheduled for phacoemulsification and intraocular lens (IOL) implantation and were willing to undergo bilateral cataract surgery. One eye of each patient was randomized to one of two groups. The dye group received 0.2 ml of trypan blue injected in the capsular bag after cortical cleanup under air. The control group (other eye of the same patient) received 0.2 ml of balanced salt solution injected in a similar manner. PCO in the central 3 mm area of IOL optic was analyzed by a masked observer using an evaluation of PCO software computer analysis system at 6, 12, 24, and 36 months.

Results:

The average age of patients was 62.05 ± 6.22 in the dye group and 64.92 ± 7.16 years in the control group. The mean PCO score at 6 months was significantly lower in the dye group (0.10 ± 0.15) than in the control group (0.22 ± 0.30). There were no significant differences in the PCO scores between the two groups from 12 to 36 months. At the end of 3 years, eight eyes in the dye group and seven in the control group required YAG capsulotomy (P = 0.21).

Conclusion:

Capsular bag irrigation of trypan blue dye decreased the PCO score at 6 months, but it had no effect at 36 months.

Prevention of posterior capsular opacification

Posterior capsular opacification (PCO) is a common complication of cataract surgery. The development of PCO is due to a combination of the processes of proliferation, migration, and transdifferentiation of residual lens epithelial cells (LECs) on the lens capsule. In the past decades, various forms of PCO prevention have been examined, including adjustments of techniques and intraocular lens materials, pharmacological treatments, and prevention by interfering with biological processes in LECs. The only method so far that seems effective is the implantation of an intraocular lens with sharp edged optics to mechanically prevent PCO formation. In this review, current knowledge of the prevention of PCO will be described. We illustrate the biological pathways underlying PCO formation and the various approaches to interfere with the biological processes to prevent PCO. In this type of prevention, the use of nanotechnological advances can play a role.

Posterior Capsule Opacification After Phacoemulsification: Annual Review

PURPOSE

The purpose of this article is to provide a clinical update on posterior capsule opacification (PCO) after phacoemulsification by reviewing the literature from the last 12 months.

DESIGN

This article is a literature review.

METHODS

The authors conducted a 1-year literature search in the English language on PCO using PubMed. The period used to conduct the literature search was from January 1, 2013, to January 1, 2014. The following search terms were used during the PubMed search: phacoemulsification, microcoaxial incision, posterior capsule opacification, long-term evaluation of intraocular lens (IOL) implantation, IOL edge design and material, surgical technique, anterior capsule overlap on the IOL optic, diabetes mellitus, myopia, pseudoexfoliation, retinitis pigmentosa, uveitis, and neodymium: yttrium-aluminum-garnet laser capsulotomy.

RESULTS

This review incorporates original articles that provided fresh insights and updates on PCO. Particular attention was paid to observational, randomized, controlled clinical trials, as well as analyses of larger cohorts with a prospective and retrospective study design. Letters to the editor, unpublished works, experimental trials and abstracts were not considered.

CONCLUSIONS

This annual review provides a brief update on PCO that might be of interest to the practicing clinical ophthalmologist.