Dye-enhanced cataract surgery. Part 1: anterior capsule staining for capsulorhexis in advanced/white cataract

Achieving successful capsulorhexis in intumescent white mature cataracts to prevent Argentinian flag sign - A new multifaceted approach to meet the challenge

Purpose:

To present a case series of intumescent white cataract cases managed by a new surgical technique to attain a single stage Continuous Curvilinear Capsulorhexis (CCC).

Methods:

The series included 60 eyes of 60 patients with white cataract which underwent preoperative anterior chamber depth, lens thickness and ultrasonographic A-scan for intralenticular spikes. A partial size main port (~1.8mm) is created as the first entry into the anterior chamber (AC). A 30-gauge needle of insulin syringe entered through a limbal stab incision is used to decompress the anterior and posterior intralenticular compartments. Following which a standard size, one stage capsulorhexis was performed in a trypan blue stained capsule using microcapsulorhexis forceps entered through the partial sized trapezoidal main port. The main port was secondarily enlarged for phacoemulsification.

Results:

Based on the intraoperative findings, 43 eyes were categorized as Intumescent type-1 cataracts i.e., with presence of actual liquefied cortex aspirated using 30-gauge needle and 17 eyes as Intumescent type-2 cataracts, i.e., presence of swollen lens without any obvious liquefied cortex. Standard size, circular and centred CCC was achieved in 100% of the cases and no Argentinean flag sign was noted. Surgeon perceived raised intralenticular pressure in 41% of the cases in type-1 subset and 61% cases in type-2 subset (P-0.06). Posterior capsular plaque was observed in 22% of the cases, adherent cortex in 25% and anterior capsular plaque in 5% of the cases. At 6weeks follow up 92% patients had best corrected visual acuity of 20/40 or better.

Conclusion:

A multi-layered approach can help in attaining successful CCC in cases of white mature cataract with high intralenticular pressure.

Real-time intraoperative dynamics of white cataract-intraoperative optical coherence tomography-guided classification and management

PURPOSE

To evaluate morphological characteristics and intraoperative dynamics of different types of white cataract using intraoperative optical coherence tomography (iOCT).

SETTING

Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi, India.

DESIGN

Prospective interventional study.

METHODS

Fifty eyes with white cataract undergoing phacoemulsification were evaluated. The primary outcome measure was the classification of white cataract based on morphology and intraoperative dynamics on iOCT. The secondary outcome measure was rhexis-related complications.

RESULTS

Four types of white cataract were identified based on iOCT-type I (9 eyes), type II (3 eyes), type III (24 eyes), and type IV (14 eyes). Type I had regularly arranged lamellar cortical fibers, type II had continuous hyperreflective bands of cortical fibers with intralenticular clefts, type III had intralenticular clefts combined with areas of homogenous ground-glass appearance, and type IV had homogenous ground-glass appearance of the anterior lens cortex. Capsulorhexis in type I cataract was uneventful. In type II cataract, cortical bulge was observed in the anterior chamber on creating the initial nick, indicating raised intralenticular pressure (ILP) with an imminent risk of rhexis extension. A bimanual irrigation/aspiration was performed until lowering of ILP was observed on iOCT. In types III and IV, fluid release was observed on initiation of rhexis leading to partial (type III) or complete (type IV) lowering of ILP, with a mild-moderate risk of capsulorhexis extension. A continuous curvilinear capsulorhexis was achieved in all cases, with no case of posterior capsular tear or vitreous loss.

CONCLUSIONS

Intraoperative OCT helped elucidate intraoperative dynamics of the spectrum of white cataracts and facilitates completion of capsulorhexis.

Capsule milking: Modification of capsulorhexis technique for intumescent cataract

We describe a single-stage modification of the continuous curvilinear capsulorhexis that facilitates creation of a well-sized round and centered capsulorhexis in an intumescent cataract. This is done without special instrumentation. The modification is based on overcoming the problem of high intralenticular pressure. It involves physically flattening the central anterior capsule, specifically over the site of puncture, simultaneous puncture and aspiration for decompression, followed by flattening of the midperiphery of the lens where the capsulorhexis can be safely initiated. This minimizes the tendency of capsulorhexis runaway and allows 1-stage creation of a well-sized capsule opening for phacoemulsification.

Evaluation of equine corneal endothelium after exposure to 0.05% brilliant blue - an in vitro study

ABSTRACT The aim of this study was to evaluate the immediate effects of 0.05% brilliant blue on corneal endothelium of horses. Thirty-eight corneas of 19 horses, male or female, of different ages were studied. Corneas were randomly divided into two groups. Group 1: Corneal endothelium was covered with 0.3mL of brilliant blue 0.05% for 60 seconds followed by rinsing with a balanced salt solution. Group 2: Corneal endothelium was covered with BSS for 60 seconds. The corneas were excised with an 8mm trephine and prepared to analyze posterior endothelial surface using a light microscope (24 corneas) and a scanning electron microscope (14 corneas). The equine posterior corneal endothelium surface observed by optical microscopy and scanning electron microscopy revealed a continuous layer of polygonal cells of uniform size and shape in both the control and treatment groups. Due to non-normal residuals at ANOVA mean comparison, a generalized linear model was utilized at 5% level of significance. The chi-square test stated that treatment and control group were not different statistically. The 0.05% brilliant blue did not cause damage to equine corneal endothelium.

Techniques of anterior capsulotomy in cataract surgery

Optimal outcomes of a cataract surgery largely depend on the successful performance of an anterior capsulotomy. It is one of the most important steps of modern cataract surgery which reduces the risk of capsular tears and ensures postoperative stable intraocular lens (IOL). Anterior capsulotomy is considered ideal if it is round, continuous, well-centered, and overlaps the implanted IOL around its circumference. If any of these features is missing, it can be a cause of impedance for desired surgical and visual outcomes. Manual can opener and manual capsulorhexis are the routine standard techniques employed for manual extracapsular cataract extraction and phacoemulsification, respectively. Recent increasing use of femtosecond laser cataract surgery has allowed cataract surgeons to obviate inherent inaccuracies of manual anterior capsulotomy techniques. There is an ongoing quest to find an ideal, risk free, and surgeon-friendly technique of anterior capsulotomy that can be employed for surgery in all types of cataracts.

Vital Dyes in Vitreomacular Surgery

Vital dyes contain complex molecules with chromophores that stain living tissues and have greatly enhanced identification and removal of transparent vitreoretinal tissues during surgery. Several "chromovitrectomy" dyes are frequently used by vitreoretinal specialists, including indocyanine green, trypan blue, brilliant blue G, and triamcinolone acetonide; other dyes are also under investigation. Trypan Blue was approved by the U.S. Food and Drug Administration (FDA) for epiretinal membrane removal, and preservative-free triamcinolone acetonide was approved by the FDA for intraocular use. However, currently available chromovitrectomy dyes have their limitations, and of particular concern for some of them is the possibility for acute and chronic toxicity to the neurosensory retina and retinal pigmented epithelium. The potentially irreversible acute toxicity and other limitations, such as lack of long-term safety profiles, highlight the need for further advancements. [Ophthalmic Surg Lasers Imaging Retina. 2018;49:788-798.].

Long-term results of surgical excision of conjunctival retention cyst using trypan blue with methylcellulose

Purpose

Conjunctival retention cysts may recur if not completely removed. However, the cyst wall often ruptures during surgical excision, making complete removal difficult. In order to ensure complete cyst excision, we used a method of staining the inner cyst wall using trypan blue augmented by Methyl cellulose.

Observation

Interventional study. Staining was performed by injecting trypan blue using an insulin needle. Then the needle was kept in place and methyl cellulose was injected to make the cyst content viscous to avoid its collapse after removing the needle. By using this technique, it was possible to excise the lesion as a whole. Three patients were included (unilateral). Two patients had cysts that were secondary to trachoma and were followed for up to 2 years without recurrence. A third patient had a conjunctival cyst following strabismus surgery was not successfully removed.

Conclusion

This method is simple and effective for complete excision of conjunctival retention cysts exception for cysts post strabismus surgery.

Comparative analysis of brilliant blue G and an intracameral illuminator in assisting visualization of the anterior capsule in eyes with vitreous hemorrhage

PURPOSE

To compare the safety and efficacy of 0.025 mg/mL brilliant blue G (BBG) and an intracameral illuminator for visualizing the anterior capsule.

SETTING

University-based tertiary referral center, South Korea.

DESIGN

Retrospective cases series.

METHODS

The medical records of patients with vitreous hemorrhage for which they had pars plana vitrectomy and cataract surgery were retrospectively reviewed. The patients were classified into 2 groups. The BBG group comprised patients having capsule staining with BBG. The illuminator group comprised patients who had capsulorhexis assisted with an intracameral illuminator. The status of the endothelial cells was analyzed.

RESULTS

There were 27 eyes in the BBG group and 35 eyes in the illuminator group. In the BBG group, endothelial cell density (ECD) was reduced 3 months after surgery (10.6% loss) (P = .003). The illuminator group had no significant loss (1.5% loss) (P = .264). The ECD loss was greater in the BBG group than the illuminator group 3 months after surgery (P = .01). There was no statistically significant difference in the coefficient of variation of cell area or percentage of hexagonal cells between the 2 groups.

CONCLUSIONS

The ECD loss was higher in eyes with 0.025 mg/mL BBG staining than in eyes using an intracameral illuminator. Further studies are necessary to establish the safety profile of BBG on the endothelium.

FINANCIAL DISCLOSURE

None of the authors has a financial or proprietary interest in any material or method mentioned.

Open-Sky Capsulorrhexis in Triple Procedure: With or without Trypan Blue?

PURPOSE

To establish the beneficial effects of trypan blue 0.1% capsule staining in open-sky capsulorrhexis during triple procedure.

METHODS

Patients who underwent penetrating keratoplasty (PK) with phacoemulsification and intraocular lens (IOL) implantation were divided into two groups. Group 1 consisted of 31 eyes of 26 patients with a mean age 64.4 +/- 6.9 years and anterior lens capsule was stained with trypan blue 0.1% to perform open-sky capsulorrhexis. In Group 2, capsulorhexis was performed without staining of the anterior capsule in 19 eyes of 17 patients with a mean age 60.6 +/- 5.3 years. The rates of complete capsulorrhexis and intra- and postoperative capsule-related complications were compared between the groups.

RESULTS

The most common diagnosis before PK was corneal opacification in both groups. Open-sky capsulorrhexis was not completed in 3 eyes (9.6%) in Group 1 and in 9 eyes (47.3%) in Group 2. The rates of incomplete capsulorrhexis, posterior capsule tear, and transscleral fixation IOL implantation were higher in Group 2 (for each, p < 0.05). The diameters of capsulorrhexis were smaller than 4.5 mm in one eye in Group 1 and in two eyes in Group 2, and larger than 6.5 mm in two eyes in Group 1 and in three eyes in Group 2. Malposition of IOL, zonular dialysis, retinal detachment, and pupil capture were only observed in eyes in Group 2. In the follow-up period, there were no adverse reactions due to application of trypan blue in Group 1.

CONCLUSIONS

Trypan blue staining of the anterior capsule during triple procedure helps the surgeon perform open-sky capsulorrhexis more easily and safely and in proper dimensions, provides positive effects on the other steps of the surgery, and decreases the rate of posterior capsule tear formation.

Modified 30 G needle trypan blue staining technique under air for a uniform and consistent anterior capsule staining

PURPOSE

To describe a trypan blue dye staining technique under air, a modification of the previously described 30 G needle under-air technique.

DESIGN

This is a prospective, randomized study of 1,000 eyes of 952 patients undergoing phacoemulsification in a private practice setting from January 2015 to August 2016. Three variants as a modification of the previously known 30 G needle technique are described. In our technique, after injecting one drop of the dye under air, the needle is kept in the anterior chamber (AC) for 15 seconds. In the second variation, along with the additional hold time, 0.05 mL air is injected prior to dye injection to deepen the AC in eyes with shallow ACs or in cases with increased posterior pressure. The third variation is the selective painting approach in which more than one drop is injected for a homogenous staining.

MAIN OUTCOME MEASURES

The main outcome measures were safety and reproducibility of the technique along with homogeneity and uniformity of the anterior capsule staining.

RESULTS

AC remained stable during the hold time of 15 seconds with no egress of air. No iatrogenic trauma occurred in any of the cases. All cases had a homogeneously stained anterior capsule. The staining intensity was excellent in 80.8% of the eyes and good in 19.2% of the eyes.

CONCLUSION

This is a safe, simple, and cost-effective technique which achieves consistent, uniform, and reproducible staining. It overcomes the shortcomings of the known 30 G needle technique.

Effects of intracameral brilliant blue on the corneal endothelium of swine: in vitro study

Abstract: The aim was to investigate the ultrastructural changes in the corneal endothelium of pigs induced by intracameral 0.05% brilliant blue. Twenty swine corneas were separated into two groups, the right eye bulbs (control group) and the left eye bulbs (experimental group) of the same animal. All the eye bulbs were evaluated with specular microscopy. The cornea of the right eye bulbs was excised and in the left eye bulbs 0.2ml of 0.05% brilliant blue vital dye (OPTH-blue±) was injected into the anterior chamber, where it remained for one minute. Then the anterior chamber was cleaned with a balanced salt solution injection and the cornea was excised too. All the corneas were evaluated by scanning electron microscopy to evaluate the changes on the endothelium caused by the brilliant blue dye. There were no significant differences between the right corneal endothelium cells and the left corneal endothelium cells with scanning electron microscopy after intracameral use of 0.05% brilliant blue dye. The 0.05% brilliant blue dye concentration did not cause deleterious effects for the swine corneal endothelium after intracameral use and can be a choice for safe staining of the anterior capsule of the lens in cataract surgery.

Under-air staining of the anterior capsule using Trypan blue with a 30 G needle

The original technique of staining the anterior capsule of the lens with Trypan blue involves the injection of an air bubble in the anterior chamber. A drawback of this technique is the possible instability of the anterior chamber caused by the sudden exit of air when the dye is injected with the cannula through the side-port incision. Other staining techniques that use viscoelastic substances to increase the stability of the anterior chamber and to dose the injected dye have been described. The authors present an under-air staining technique of the anterior capsule using one drop of Trypan blue injected with a 30 G needle through the peripheral cornea. This procedure prevents the air bubble from escaping the anterior chamber and allows fast and selective staining of the capsule.

Comparison of capsulorhexis resistance to tearing with and without trypan blue dye using a mechanized tensile strength model

PURPOSE

To evaluate the influence of trypan blue staining on capsulorhexis tear resistance using a model for mechanical measurement of the entire capsular bag of fresh human cadaver eyes.

SETTING

John A. Moran Eye Center, University of Utah, Salt Lake City, Utah, USA.

DESIGN

Experimental study.

METHODS

After the cornea and iris were removed, a 5.0 to 5.5 mm anterior continuous curvilinear capsulorhexis (CCC) was created; the capsule in study eyes was stained with trypan blue. The nucleus was hydroexpressed and the capsular bag was evacuated by irrigation/aspiration. Two metal shoetree-shaped fixtures were implanted separately in the capsular bag and assembled using a screw nut. After zonulectomy, the fixture-capsular bag assembly was removed from the eye and loaded onto a mechanized tester. The fixtures were separated at a velocity of 7.0 mm/min in 0.15 μm intervals to stretch the capsulorhexis to its rupture point. A graph was generated for each eye.

RESULTS

Ten study eyes were compared with 23 control eyes. The groups were comparable in donor age, time from death, and CCC diameter. The mean rupture load was 0.40 Newton (N) ± 0.13 (SD) in the trypan blue group and 0.39 ± 0.16 N in the control group (P=.94). The mean extension was 5.70 ± 0.99 mm and 5.85 ± 1.17 mm, respectively (P=.74).

CONCLUSIONS

There was no difference in CCC strength between trypan blue-stained capsules and control capsules. Staining with trypan blue did not reduce CCC tear resistance.

FINANCIAL DISCLOSURE

No author has a financial or proprietary interest in any material or method mentioned.

Unintentional staining of the posterior lens capsule with trypan blue dye during phacoemulsification: case report

We report a complication related to the use of trypan blue during capsular staining of the anterior lens capsule during phacoemulsification surgery. In phacoemulsification surgery of the left eye, trypan blue was injected using an air bubble technique. Unintentionally, trypan blue was administered under high pressure, dispersing the dye through the zonules leading to staining of the posterior capsule. This caused a temporary disturbance of visual acuity during the postoperative period.

Trypan blue dye for anterior segment surgeries

Use of vital dyes in ophthalmic surgery has gained increased importance in the past few years. Trypan blue (TB) has been a popular choice among anterior segment surgeons mainly due to its safety, ease of availability, and remarkable ability to enable an easy surgery in difficult situations mostly related to visibility of the targeted tissue. It is being used in cataract surgery since nearly a decade and its utilization has been extended to other anterior segment surgeries like trabeculectomy and corneal transplantation. This review will discuss the techniques and outcome of TB dye-assisted anterior segment surgeries.

Retinal nerve fiber layer thickness evaluation after trypan blue-assisted macular surgery

PURPOSE

The purpose of this study was to evaluate retinal nerve fiber layer (RNFL) thickness changes in eyes undergoing trypan blue-assisted macular surgery using optical coherence tomography-3. This is a prospective noncomparative, interventional, and observational case series of 35 eyes of 35 consecutive patients (15 eyes with macular hole, 14 eyes with idiopathic macular pucker, and 6 eyes with tractional diabetic macular edema) who underwent pars plana vitrectomy and peeling of the epiretinal membrane and/or internal limiting membrane assisted with 0.1 mL of 0.15% trypan blue.

METHODS

The quantitative analysis of the peripapillary RNFL by optical coherence tomography was performed before surgery and 6 months postoperatively in both eyes of the same patient. The main outcome measures were significant changes in RNFL thickness (overall and by quadrant).

RESULTS

Optical coherence tomography assessment of the macular status at 6 months postoperatively showed closure of all macular holes and improvement in foveal contour in all cases of macular pucker or most cases of diabetic macular edema. Dissociated RNFL at the area of internal limiting membrane removal was observed in 9 eyes. No statistical significant changes in the mean RNFL thickness overall or by quadrant were observed after surgery.

CONCLUSION

Trypan blue-assisted peeling of macular epiretinal membranes and/or internal limiting membrane does not induce significant changes in RNFL thickness as measured by optical coherence tomography-3. Internal limiting membrane peeling may induce visible changes of the inner retinal surface possibly because of microdefects on macular nerve fiber layers.

Ability of new vital dyes to stain intraocular membranes and tissues in ocular surgery

PURPOSE

To evaluate the ability of novel dyes to stain lens capsule (LC), internal limiting membrane (ILM), epiretinal membrane (ERM), and vitreous.

DESIGN

Experimental study in animal and human donor eyes.

METHODS

Thirteen dyes, methyl violet, crystal violet, eosin Y, sudan black B, methylene blue, toluidine blue, light green, indigo carmine, fast green, congo red, evans blue, brilliant blue, and bromophenol blue, were injected onto the LC and ILM of enucleated porcine eyes. The vitreous was stained with 2 mL of dyes for 1 minute. Six dyes (indigo carmine, evans blue, fast green, light green, bromophenol blue, and brilliant blue) were selected for experiments in human donor eyes and freshly removed ERM.

RESULTS

In the porcine eyes, ILM staining with methylene blue, toluidine blue, indigo carmine, evans blue, bromophenol blue, and fast green was moderate, and methyl violet, crystal violet, brilliant blue, or sudan black resulted in strong staining. Methyl violet, crystal violet, sudan black, toluidine blue, and methylene blue caused histologic damage in porcine retinas. Vitreous examination revealed moderate staining with congo red, crystal violet, fast green, eosin Y, methylene blue, toluidine blue, brilliant blue, bromophenol blue, and methyl violet and strong staining with light green and evans blue. ERMs showed strong staining with 0.5% evans blue and moderate staining with 0.5% light green, fast green, brilliant blue, and bromophenol blue. Evaluation of donor eyes disclosed moderate staining with evans blue, light green, and bromophenol blue and strong staining with 0.5% brilliant blue. Moderate or strong staining of the vitreous occurred with most dyes. LC evaluation showed moderate staining with 0.5% evans blue, fast green, and brilliant blue, whereas 0.5% light green produced strong LC staining.

CONCLUSIONS

Brilliant blue shows the best ILM staining, whereas bromophenol blue, evans blue, and light green also stain ILM. Most dyes bind well to LC, vitreous, and ERM.

Toxicity of Indocyanine Green (ICG) in Combination with Light on Retinal Pigment Epithelial Cells and Neurosensory Retinal Cells

PURPOSE

To evaluate the toxicity of indocyanine green (ICG) in combination with light.

METHODS

Human retinal pigment epithelial cells (ARPE-19) and rat neurosensory retinal cells (R28) were treated with four different concentrations of ICG in combination with light exposure. Cell viability, mitochondrial function, and DNA synthesis were measured.

RESULTS

All concentrations of ICG with 10 min of light exposure caused a significant decrease in mitochondrial dehydrogenase activity in R28 and ARPE-19 cells. ICG without light exposure did not decrease mitochondrial dehydrogenase activity. In both cell lines, [(3)H]thymidine incorporation was increased when treated with ICG with or without light. R28 cells did not show any significant decrease in cell viability.

CONCLUSIONS

The duration of light was a significant factor in ICG toxicity. ICG needs to be used with caution as it decreases the mitochondrial dehydrogenase activity and increases the DNA synthesis in retinal cells, markers for cell toxicity and dysfunction.

Automated vitrector-assisted iridectomy and phacoemulsification in eyes with coexisting cataract and adherent leucomas

PURPOSE

To describe a surgical technique as an alternative to allograft corneal transplantation for management of cases with cataract and corneal opacity.

METHODS

Seven eyes of seven patients with adherent leucomas and cataract underwent phacoemulsification with intraocular lens (IOL) implantation. An automated vitrector was used to release the adherent leucoma and create an optical iridectomy at the start of surgery. Phacoemulsification with IOL implantation was performed in all eyes. The release of the iris adherence along with creation of an optical iridectomy improved visualization during phacoemulsification.

RESULTS

Phacoemulsification and IOL implantation could be performed successfully in all seven eyes. The median best-corrected visual acuity (BCVA) improved from 1/60 (range: (light perception) 6/36) preoperatively to 6/18 (range: 6/36-6/12) at last follow-up (average: 41 days).

CONCLUSIONS

This surgical technique is a viable option in cases with partial corneal opacification with coexisting cataract.

Indocyanine green-assisted phacoemulsification in cases of complicated or simple advanced cataracts

BACKGROUND/PURPOSE

During phacoemulsification for advanced cataracts, particularly when complicated by anterior segment abnormalities, capsulorhexis is very difficult and carries a high risk of complications. This study investigated the efficacy and safety of indocyanine green (ICG)-assisted phacoemulsification in complicated or simple advanced cataracts.

METHODS

Thirty-two patients (35 eyes) underwent phacoemulsification for complicated advanced cataracts (group 1) or simple advanced (mature/hypermature) cataracts (group 2). Anterior segment abnormalities (corneal opacity, small pupil, or glaucoma) in group 1 complicated phacoemulsification. In both groups, 0.5% ICG was used for capsulorhexis, and subsequent procedures were performed in the same routine manner.

RESULTS

Group 1 included 15 patients (17 eyes) with a mean age of 60.0 years. Group 2 included 17 patients (18 eyes) with a mean age of 69.4 years (p<0.05). Continuous curvilinear capsulorhexis was completed in all eyes in group 2, but radial tears occurred in four (23.5%) eyes in group 1 (p<0.05). Phacoemulsification was performed uneventfully in all eyes in both groups. Postoperative complications (corneal edema, vitreous prolapse, posterior capsule opacity, elevated intraocular pressure) were seen in five (27.8%) eyes in group 1 and four (23.5%) eyes in group 2 (p>0.05). None of these were attributed to the use of ICG. Visual acuity improved in all eyes in group 2, but in only 11 (64.7%) in group 1 (p<0.01).

CONCLUSION

ICG-assisted phacoemulsification is safe and helpful for complicated or simple advanced cataracts. Differences between the two groups in patient age, intraoperative complications, and visual outcome could be explained by differences in the cause(s) of advanced cataracts.

Subtle signs of anterior vitreous face disturbance during posterior capsulorhexis in pediatric cataract surgery

In 4 patients with congenital cataract, subtle signs of anterior vitreous face (AVF) disturbance were documented during posterior continuous curvilinear capsulorhexis. The signs were vitreous strands in the anterior chamber, vitreous strands attached to the capsule flap, and distortion of the anterior and posterior capsulorhexis margins; the latter is considered a pathognomonic sign of AVF disturbance. As a result of the early recognition, modifications to the cataract surgery technique were made.

[Trypan blue capsule staining for phacoemulsification in white cataract]

OBJECTIVE

To study the results of phacoemulsification in eyes with white cataract using trypan blue for capsule staining.

PATIENTS AND METHODS

Thirty patients who had white cataract were included in this prospective study. They had phacoemulsification and continuous curvilinear capsulorhexis using trypan blue. Intraoperative problems related to capsulorhexis and phacoemulsification as well as postoperative outcomes where analyzed. Postoperative examinations were done at 1 day, 1 week, and 1, 3, 6, and 12 months. The mean follow-up was 10 months.

RESULTS

Complet capsulorhexis was achieved in 26 cases. Intraoperative complications included incomplet capsulorhexis in four cases (13.3%) and conversion to a conventional extraction technique in two cases. There were no cases of posterior capsular tear. Twenty-eight eyes (93.3%) had a final best corrected visual acuity at 8/10 or better. Postoperative complications included moderate transient corneal edema in six cases (20%) and iritis in three cases (10%). There were no complications related to the use of trypan blue.

CONCLUSION

Phacoemulsification using trypan blue was safe and effective in managing white cataract and had a high success rate.

Corneal Edema and Permanent Blue Discoloration of a Silicone Intraocular Lens by Methylene Blue

BACKGROUND AND OBJECTIVE

To report a silicone intraocular lens (IOL) stained blue by inadvertent intraoperative use of methylene blue instead of trypan blue and the results of experimental staining of various lens materials with different concentrations of the same dye.

MATERIALS AND METHODS

A "blue dye" was used to enhance visualization during capsulorhexis in a patient undergoing phacoemulsification with implantation of a three-piece silicone lens. Postoperatively, the patient presented with corneal edema and a discolored IOL. Various IOL materials were experimentally stained using methylene blue. Sixteen lenses (4 silicone, 4 hydrophobic acrylic, 4 hydrophilic acrylic, and 4 polymethylmethacrylate) were immersed in 0.5 mL of methylene blue at concentrations of 1%, 0.1%, 0.01%, and 0.001%. These lenses were grossly and microscopically evaluated for discoloration 6 and 24 hours after immersion.

RESULTS

The corneal edema resolved within 1 month after the initial surgical procedure. After explantation, gross and microscopic analyses of the explanted silicone lens revealed that its surface and internal substance had been permanently stained blue. In the experimental study, all of the lenses except the polymethylmethacrylate lenses were permanently stained by methylene blue. The hydrophilic acrylic lenses showed the most intense blue staining in all dye concentrations.

CONCLUSIONS

This is the first clinicopathological report of IOL discoloration due to intraocular use of methylene blue. This and other tissue dyes may be commonly found among surgical supplies in the operating room and due diligence is necessary to avoid mistaking these dyes for those commonly used during ocular surgery.

Effect of trypan blue staining on the density and viability of lens epithelial cells in white cataract

PURPOSE

To assess the effect of anterior capsule staining with trypan blue 0.0125% on the density and viability of the lens epithelial cells (LECs).

SETTING

Iladevi Cataract and IOL Research Center, Ahmedabad, India.

METHODS

This randomized prospective study comprised 40 eyes having phacoemulsification for white mature cataract. Patients were randomized to have the anterior capsule stained with 0.1 mL trypan blue 0.0125% solution before the anterior capsulorhexis (Group 1, n = 20) or to have no anterior capsule staining before the anterior capsulorhexis (Group 2, n = 20). The density and viability of LECs were analyzed. The first 20 samples (10 from Group 1, 10 from Group 2) were stained with hematoxylin-eosin for cell density analysis using image-analysis software. The remaining 20 samples (10 from each group) were stained with a solution containing 0.5 microM calcein AM and 5 microM propidium iodide for 10 minutes at 37 degrees C for viability assay.

RESULTS

The mean cell density in Group 1 (with staining) was 3533.15 cells/mm(2) +/- 664.01 (SD). This was significantly lower than the mean of 4235.59 +/- 414.93 cells/mm(2) in Group 2 (no staining) (P = .01). The mean capsule area covered with LECs (80.75% +/- 8.04% versus 94.63% +/- 3.78%) and the mean live LECs in the covered area (51.69% +/- 11.54% versus 68.67% +/- 9.15%) were also significantly lower in Group 1 (P = .002).

CONCLUSION

Staining the anterior capsule with trypan blue affected the density and viability of LECs.

A comparison of the effectiveness of four biostains in enhancing visualization of the vitreous

PURPOSE

To compare the effectiveness of four biostains in vitreous staining as a means to facilitate clean anterior vitrectomy.

MATERIALS AND METHODS

Four biostains (fluorescein, indocyanine green, trypan blue, and triamcinolone acetonide) were used to stain the transparent vitreous of human cadaver and monkey cadaver eyes. Results were compared and recorded by digital photography and videography.

RESULTS

Of the four biostains, triamcinolone acetonide best highlighted the vitreous. Although fluorescein, indocyanine green, and trypan blue also produced acceptable vitreous staining, the surrounding ocular structures were slightly stained as well.

CONCLUSION

All four biostains enhanced visualization of the vitreous. However, triamcinolone acetonide best highlighted the vitreous.

Updates on the Surgical Management of Paediatric Cataract with Primary Intraocular Lens Implantation

With the advent of modern surgical techniques, paediatric cataract has become much more manageable. Intraocular lens (IOL) implantation is the standard of care for patients over the age of 2 years. The use of IOL in young infants is still controversial. In addition, there are still unresolved issues, such as the minimum age at which IOL can be safely implanted, IOL power selection and IOL power calculation. The current trends in the management of the above challenges are discussed. Although numerous reports on the prevention and management of posterior capsule opacification have been published, there are ongoing intensive debates and research. Long-term postoperative complications like glaucoma and rhegmatogenous retinal detachment are problems that cannot be overemphasised and these issues are also reviewed. Key words: Congenital cataract, Intraocular lens, Posterior capsule opacification

Capsule Staining as an Adjunct to Cataract Surgery

OBJECTIVE

This document evaluates currently available data in the published literature to answer the question of whether the use of dye such as indocyanine green or trypan blue to stain the lens capsule to improve visualization is safe and effective as an adjunct to cataract surgery.

METHODS

Literature searches conducted in March 2003 and May 2004 retrieved 139 citations. The panel members reviewed the abstracts and selected 47 of possible clinical relevance for review. An additional 14 articles were identified for evaluation. Of the 61 articles reviewed, the panel members selected 36 for the panel methodologist to review and rate according to the strength of the evidence. A level I rating was assigned to properly conducted, well-designed, randomized clinical trials; a level II rating was assigned to well-designed cohort and case-control studies; and a level III rating was assigned to case series and case reports.

RESULTS

There is level III evidence that indocyanine green, trypan blue, and fluorescein are each effective in staining the lens capsule and that indocyanine green and trypan blue provide better ease of use and visualization of the capsule than fluoroscein. There is level II evidence that staining the capsule is helpful in completing capsulorrhexis and that it is helpful for pediatric patients under age 5 years and in cases of white cataract. The overall surgical advantage of a completed continuous curvilinear capsulorrhexis using dye has not been demonstrated, but this may be related to the outcome measures chosen rather than a failure to confer advantage. There are substantial data indicating that trypan blue 0.1% is not toxic to the cornea. There are limited data suggesting that indocyanine green 0.125% to 0.5% is not toxic to anterior segment structures.

CONCLUSIONS

There are data confirming that dye is safe and effective as an adjunct for capsule visualization in cataract surgery. It is reasonable to use dye when inadequate capsule visualization may compromise the outcome in cataract surgery. More studies are needed to confirm a lack of toxicity of indocyanine green and trypan blue, particularly in the event of posterior segment or longer duration exposure.

Retained posterior segment indocyanine green dye after phacoemulsification

We describe a patient who had indocyanine green (ICG) staining of the anterior capsule for phacoemulsification of a traumatic cataract. Intraoperatively, the ICG extended into the posterior segment. Postoperatively, the patient developed ICG toxicity to the retina and had a vitrectomy to remove the ICG. We believe ICG extended into the vitreous through an area of zonular dehiscence.

Capsular staining: recent developments

PURPOSE OF REVIEW

This paper reviews the recent literature regarding anterior capsular staining.

RECENT FINDINGS

Safety and efficacy of dyes used in facilitating visualization of the anterior capsule during phacoemulsification are compared. Advantages of using different techniques for injection of the dyes are discussed.

SUMMARY

Trypan Blue and Indocyanine Green appear to be most effective in staining the anterior capsule with the highest safety profile. Injection strategies should be aimed at reducing uncontrolled dispersion especially into the vitreous.

A prospective study on trypan blue capsule staining under air vs under viscoelastic

AIM

To compare the safety and effectiveness of trypan blue capsule staining under air vs under viscoelastic.

METHODS

A total of 52 consecutive patients planned for phacoemulsification of white mature cataract were randomly assigned to trypan blue staining under air or under viscoelastic. Perioperative changes in best-corrected visual acuity (BCVA), central corneal thickness (CCT), and endothelial cell density (ECD) were compared between the two groups. The differences in operating and phacoemulsification times, staining pattern, and complications between the two groups were also recorded.

RESULTS

Phacoemulsification of white mature cataract was performed in 50 (96%) eyes. The median preoperative BCVA was hand movement. No significant differences in the baseline characteristics were found between the two groups. At 3 months after phacoemulsification, the median BCVA improved to 0.8. The mean CCT returned to preoperative level by 1 month postoperatively and the mean ECD loss was 11.9% 3 months postoperatively. No significant differences in median BCVA, mean phacoemulsification and operation times, mean CCT, and mean ECD were found between the two groups.

CONCLUSIONS

Trypan blue staining of the anterior lens capsule under air or under viscoelastic were similarly effective and safe methods for the phacoemulsification of white mature cataract.

Visualization of Conjunctival Cyst Using Healon V and Trypan Blue

PURPOSE

To report a new modified method using the mixture of an ophthalmic viscosurgical devices (Healon V) and trypan blue solution to facilitate complete removal of a conjunctival cyst.

METHOD

A 54-year-old woman was referred to us for removal of a conjunctival cyst in her right eye. To achieve a complete removal of the conjunctival cyst, a mixture of Healon V and trypan blue solution was injected through a 27-gauge needle into the cyst.

RESULTS

This new technique achieved excellent visualization with an easy and complete resection of the cyst.

CONCLUSIONS

The mixture of Healon V and trypan blue is effective in delineating the capsule while preserving its integrity during removal. Such a technique may also have a role in facilitating visualization and excision of other cystic conjunctival lesions.

Photodynamic actions of indocyanine green and trypan blue on human lens epithelial cells in vitro

PURPOSE

The purpose of this study was to evaluate the toxicity and photodynamic activity of indocyanine green (ICG) and trypan blue (TryB) on cultured human lensepithelial cells (LECs).

DESIGN

Experimental study.

METHODS

Lens epithelial cell viability was assessed after treatment with ICG and TryB concentrations ranging from 0.025 to 5.0 mg/ml, and exposure to 806 nm diode laser.

RESULTS

At ICG concentrations below 0.5 mg/ml, there was > or =75% cell viability; at higher ICG concentrations there was dose-dependent cytotoxicity in addition to loss of cellular viability due to ICG photosensitization. TryB had little cytotoxicity to the LECs: >80% cells were viable irrespective of the dye concentration or laser treatment.

CONCLUSIONS

These data indicate that ICG may have application as a photosensitizer in the selective eradication of residual LECs after cataract surgery to reduce the incidence of posterior capsule opacification.

Comparison of dyes for cataract surgery. Part 1: cytotoxicity to corneal endothelial cells in a rabbit model

PURPOSE

To investigate the corneal endothelial cytotoxicity of dyes for capsule staining in cataract surgery.

SETTING

Department of Ophthalmology and Institute of Clinical Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.

METHODS

Cultured corneal endothelial cells of New Zealand white rabbits were exposed for 1 minute to 1 of the following dyes (various concentrations): indocyanine green (ICG), methylene blue (MB), gentian violet (GV), trypan blue (TB), and fluorescein sodium (FS). The degree of cell damage was determined by in vitro staining with TB and comparison with results in a control group. The effect of longer exposure (up to 10 minutes) to ICG 0.25% was also investigated. Structural changes in corneal endothelial cells after dye exposure were evaluated by light microscopy and transmission electron microscopy (TEM).

RESULTS

Indocyanine green 0.25%, MB 0.20%, GV 0.01%, TB 0.40%, and FS 10% did not induce significant damage to corneal endothelial cells. Significant cytotoxicity was observed with the following or higher dye concentrations: ICG 0.50%, MB 0.50%, and GV 0.10%. Exposure to ICG 0.25% for 1 to 10 minutes showed a trend toward cytotoxicity after 10 minutes. On TEM, corneal endothelial cells that had been exposed to ICG 0.50% showed remarkable organelle swelling and disruption, electron-dense granules, and cell lysis.

CONCLUSION

One minute of exposure to ICG 0.25%, MB 0.20%, GV 0.01%, TB 0.40%, and FS 10% appeared to be safe as determined by no cytotoxic effects on rabbit corneal endothelial cells in culture.