Phacoemulsification of white mature cataracts

Application of Femtosecond Laser in Challenging Cataract Cases

Femtosecond laser can provide precise and customized incision of ocular tissue with excellent accuracy and predictability. Thus, femtosecond laser-assisted cataract surgery (FLACS) can theoretically enhance the safety and efficacy of cataract surgery by providing reproducible and reliable clear corneal incision, limbal relaxing incision, anterior capsulotomy, and lens fragmentation. However, thus far, the superiority of the anatomical and visual outcomes of FLACS over those of conventional cataract surgery have been unclear. Nevertheless, studies have indicated that FLACS can potentially be helpful in improving the safety of cataract surgery in challenging situations, such as zonular weakness, preexisting capsular tear, white cataract, shallow anterior chamber, and pediatric cataracts, which may contribute to enhanced visual and anatomical outcomes. In this review, we provide a summary of the application of femtosecond laser in general cataract cases. In addition, we introduce the application of FLACS in the abovementioned challenging situations and discuss the results of studies regarding the safety and outcome of FLACS in these challenging cases.

A safe and successful capsulorhexis technique for the intumescent cataracts; modified two-stage continuous curvilinear capsulorhexis

BACKGROUND

Capsulorhexis is the most important step in intumescent cataract due to the high risk of radial extension of the capsular tear during the cataract surgery. The aim of this study is to present modified the two-stage capsulorhexis technique for intumescent cataract.

MATERIALS AND METHODS

The two-stage capsulorhexis technique was used in this study. A small size capsulorhexis approximately 1.5-2 mm diameter was created in the first stage. Liquefied cortex was aspirated with a 25 G cannula to equalize anterior chamber pressure and intracapsular pressure after the small size capsulorhexis. In the second stage, a 5-6 mm capsulorhexis size was performed for a safe phacoemulsification.

RESULTS

A total of 73 consecutive patients with intumescent cataract were evaluated in this study. There were 39 male cases and 34 female cases. Mean age was 66 years ± 8 (between 53 and 84 years). A well centered complete continuous curvilinear capsulorhexis approximately 5-6 mm size was achieved in 72 of 73 cases (98.6%). Peripheral extension of capsulorhexis occurred in one eye during the second stage capsulorhexis. In this case, the capsule was cut with Vannas scissors and the capsulorhexis was completed. The rest of surgery was continued with a standard procedure and in-the-bag IOL implantation was done.

CONCLUSIONS

This technique facilitates the creation of a safe capsulorhexis compared to the one-stage capsulorhexis technique. Surgeons may consider this technique to perform a safe phacoemulsification in the intumescent cataracts.

Novel nucleus management technique in hypermature morgagnian cataracts with liquified cortex during phacoemulsification

PURPOSE

To describe a novel nucleus management technique of variable size mobile nucleus in Hypermature Morgagnian cataracts.

METHODS

In this technique, under topical anesthesia, temporal tunnel incision and capsulorhexis were performed, and the capsular bag was inflated with 2% w/v hydroxypropylmethylcellulose. A chopper and phacoemulsification probe were used to consciously nudge the nucleus towards the capsular periphery (fornix) to immobilize the floating nucleus against the capsular bag recess. Firm nuclear impaling was achieved using longitudinal power in linear mode (range 0-70%), 650 mmHg vacuum, and aspiration flow rate of 42 ml/min. The nucleus was chopped by direct chop technique, total separation achieved, and fragments emulsified. Primary outcome measures included ease of nuclear holding, iatrogenic zonular stress/damage, posterior capsule tear, and endothelial cell loss.

RESULTS

This technique was performed in 29 consecutive cases from June 2019 - December 2021, and no intraoperative or postoperative complications were noted. The average phacoemulsification time and cumulative dissipated energy (CDE) were nearly similar in all cases.

CONCLUSION

This technique would make phacoemulsification much safer in eyes with hypermature cataract and liquified cortex with lower complication rates and maintenance of better endothelial integrity.

Why Use Ultrashort Pulses in Ophthalmology and Which Factors Affect Cut Quality

The power density of femtosecond lasers and exposure time to the tissue are crucial for a successful procedure in terms of safety and precision. The reduction of the pulse duration allows reducing the quantity of the energy to be delivered to the tissue for disruption with strongly diminished mechanical and thermal collateral damage. The cutting effect of ultra-short pulses is very precise, minimally traumatic, safe, and predictable. Future developments will lead to further energy reductions to achieve optical breakdowns. However, the pulse length cannot be shortened arbitrarily because below 100 fs nonlinear effects can change the process in an unfavorable way. Compared to manual-conventional cataract surgery, femtosecond laser-assisted cataract surgery (FLACS) shows many advantages in clinical application, especially with regard to precision and tissue protection. The femtosecond laser has become particularly important and has made the overall procedure safer when we deal with complex cataract cases such as subluxated lenses. We provide an overview of the evolution of femtosecond laser technology for use in refractive and cataract surgeries. This article describes the advantages of available laser platforms with ultrashort pulses and mainly focuses on the technical and physical backgrounds of ophthalmic surgery technologies.

The benefits and drawbacks of femtosecond laser-assisted cataract surgery

INTRODUCTION

Since the introduction, femtosecond laser-assisted cataract surgery was believed to revolutionize cataract surgery. However, the judgment of clinical benefit was found to be far more complex than initially might have been thought. The aim of this review was to analyze the benefits and drawbacks of femtosecond laser-assisted cataract surgery compared with traditional phacoemulsification cataract surgery.

METHODS

PubMed and the Web of Science were used to search the medical literature. The following keywords were searched in various combinations: femtosecond laser, femtosecond laser-assisted cataract surgery, phacoemulsification cataract surgery, FLACS.

RESULTS

The benefits of femtosecond laser-assisted cataract surgery include lower cumulated phacoemulsification time and endothelial cell loss, perfect centration of the capsulotomy, and opportunity to perform precise femtosecond-assisted arcuate keratotomy incisions. The major disadvantages of femtosecond laser-assisted cataract surgery are high cost of the laser and the disposables for surgery, femtosecond laser-assisted cataract surgery-specific intraoperative capsular complications, as well as the risk of intraoperative miosis and the learning curve.

CONCLUSION

Femtosecond laser-assisted cataract surgery seems to be beneficial in some groups of patients, that is, with low baseline endothelial cell count, or those planning to receive multifocal intraocular lens. Nevertheless, having considered that the advantages of femtosecond laser-assisted cataract surgery might not be clear in every routine case, it cannot be considered as cost-effective.

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.

Precision pulse capsulotomy in challenging cataract surgery cases

Purpose

To evaluate the use of the precision pulse capsulotomy (PPC) device for challenging cataract surgery cases.

Patients and methods

This single-center retrospective case series study comprised of 43 eyes (from 35 patients) that were challenging cataract surgery cases with poorly dilated pupils, anterior subcapsular opacity, white cataract, brunescent cataract, and corneal opacity. This was  conducted at the Busan Sungmo Eye Hospital (Busan, Republic of Korea) to assess the performance of the PPC device through a 2.2-mm clear corneal incision width, followed by the phacoemulsification technique and intracapsular intraocular lens fixation. The main outcome measurement was the anterior capsulotomy performance of the PPC device and the development of intraoperative complications. At postoperative 2 months, visual acuity, endothelial cell count, and refractive error were measured.

Results

No cases of anterior capsule tears or tags occurred. All 43 eyes received circular, 360-degree, free-floating, and appropriately sized anterior capsulotomies. During 2 months of follow up, no postoperative complications occurred in association with the PPC device.

Conclusion

The PPC device facilitated the creation of a precise, round, appropriately sized anterior capsulotomy in challenging cataract surgery cases. Further investigations are required to understand the long-term safety and efficacy of the PPC device.

Advances in capsulorhexis

PURPOSE OF REVIEW

Continuous curvilinear manual capsulorhexis is currently the standard of cataract surgery. In the past several years, new technologies have been developed to improve the consistency and safety of capsulorhexis creation. This article reviews the most recent technologies in capsulotomy formation and their advantages and disadvantages.

RECENT FINDINGS

Guidance devices, femtosecond laser capsulotomy and precision pulse capsulotomy improve the centration, circularity and precision of anterior capsulorhexis and capsulotomy. These developments show particular promise for complex cataract surgeries, though clinical data on the refractive outcomes and complication rates of these technologies are currently limited and warrant additional investigation.

SUMMARY

New technological advances in capsulorhexis help surgeons achieve a more ideal capsulotomy geometry. Whether this translates into more predictable refractive outcomes and safer surgeries remains an area of future study.

A multipronged approach to prevent Argentinian flag sign in intumescent cataracts

In this communication, we describe a technique for creation of a single stage, adequately sized capsulorrhexis in intumescent cataracts by depressurizing the anterior and posterior intralenticular compartments in a nonleaky anterior chamber (AC) to prevent capsulorrhexis extension and Argentina flag sign. Initially, an incomplete main-port incision is made by the partial entry of a 2.2-mm keratome. A cohesive dispersive ophthalmic viscosurgical device (OVD) is injected into AC. Standard side-port incisions are made, followed by anterior capsular staining. The fluid cortex in anterior intralenticular compartment is aspirated by puncturing anterior capsule in the center using a 30-gauge needle entered through a separate limbal stab incision. The nucleus edge is gently tipped posteriorly with the needle tip to release the fluid from posterior intralenticular compartment also and as much fluid aspirated as possible. OVD is again injected and capsulorrhexis is performed in a single stage using micro-capsulorrhexis forceps.

Femtosecond laser-assisted cataract surgery for the white cataract

Aim

To report the capsulotomy and lens fragmentation outcomes of white cataracts managed with the femtosecond laser (FL).

Methods

Outcomes of a prospective, observational consecutive case series of white cataracts (June 2012–November 2016) that underwent FL-assisted cataract surgery (FLACS) (Victus, Bausch+Lomb, Munich, Germany) at the Singapore National Eye Centre were audited. Data collected: patient demographics, type of white cataract, levelness of docking, anterior capsule position following laser, completeness of capsulotomy and fragmentation, best-corrected visual acuity (BCVA) at 1 month, intraoperative complications. Outcome measures: capsulotomy integrity, fragmentation capability and BCVA at 1 month.

Results

58 eyes of 54 patients underwent FLACS. White cataract types included dry white (24 eyes), intumescent (28 eyes) and Morgagnian (6 eyes). Docking was level in 22 eyes (38.6%). Following FL, the anterior capsule level dropped in 20 eyes (34.5%). Incomplete capsulotomies occurred in 10 eyes (17.2%). Lens fragmentation attempted in 38 eyes was effective or partially effective in 31 eyes (81.6%). No anterior or posterior capsule tears occurred. LogMAR BCVA at 1 month was 0.073 (SD 0.09). Risk factors for incomplete capsulotomy were Morgagnian cataract and lens thickness (multiple logistic regression, p<0.01 and p=0.03, respectively).

Conclusion

The main complication of FLACS in white cataracts was incomplete capsulotomy (17.2%), significantly associated with Morgagnian cataracts and increased lens thickness. Lens fragmentation was effected in four-fifths of white cataracts but should be avoided in Morgagnian cataracts due to possible overlap of the lens fragmentation plan and the anterior capsule.

Femtosecond laser-assisted versus phacoemulsification for cataract extraction and intraocular lens implantation: clinical outcomes review

PURPOSE OF REVIEW

Femtosecond laser-assisted cataract surgery (FLACS) has gained popularity in recent years with the new technology suggesting potential improvements in clinical and safety outcomes over conventional phacoemulsification cataract surgery (PCS). A decade since the advent of FLACS has given time and experience for laser technology to develop in maturity, and better quality evidence to become available. This review evaluates current evidence on the clinical and safety outcomes for FLACS in comparison to PCS.

RECENT FINDINGS

FLACS technology continues to improve and with it our confidence in tackling more complex patient indications. Concurrently other new technologies such as precision pulse capsulotomy also look to deliver the biomechanically ideal 5.2 mm capsulotomy, particularly as there remain suggestions from large studies and meta-analyses of raised capsular complications with FLACS compared with PCS and IOL technology responding to advantages of a consistent capsulotomy. Visual benefits of FLACS over and above PCS also remain to be conclusively demonstrated, with equivalence but not superiority. Economic modelling continues to indicate that FLACS remains 'not' cost-effective.

SUMMARY

FLACS can be considered non-inferior to conventional PCS in term of safety and clinical outcomes. However, FLACS has yet to demonstrate an overall cost-benefit to the patient.

Update and clinical utility of the LenSx femtosecond laser in cataract surgery

The introduction of femtosecond lasers to cataract surgery has been the major disruptive technology introduced into ophthalmic surgery in the last decade. Femtosecond laser cataract surgery (FLACS) integrates high-resolution anterior segment imaging with a femtosecond laser allowing key steps of cataract surgery to be performed with computer-guided laser accuracy, precision, and reproducibility. Since the introduction of FLACS, there have been significant advances in laser software and hardware as well as surgeon experience, with over 250 articles published in the peer-reviewed literature. This review examines the published evidence relating to the LenSx platform and discusses surgical techniques, indications, safety, and clinical results.

Assessment of intraoperative complications in intumescent cataract surgery using 2 ophthalmic viscosurgical devices and trypan blue staining

PURPOSE

To evaluate intraoperative complications during capsulorhexis and phacoemulsification in intumescent white cataracts using 2 ophthalmic viscosurgical device (OVD) techniques.

SETTING

Ruhr University Eye Clinic, Bochum, Germany.

DESIGN

Case series.

METHODS

Patients with eyes with intumescent white cataract were recruited and placed in 2 groups. After capsule staining using trypan blue, a central indentation of the anterior lens capsule was created in the eyes in Group 1 using a medium-viscosity OVD (Healon 1.0%) and in the eyes in Group 2 using both medium-viscosity (1.0%) and high-viscosity (2.3%) OVDs. Then a continuous curvilinear capsulorhexis (CCC) was performed. The outcomes measured were the horizontal and vertical diameters of the CCC, the deviation from the target diameter, and intraoperative complications.

RESULTS

In Group 1 (21 eyes), deviation from the target CCC diameter occurred in 12 eyes (10 oversized, 2 undersized), and in Group 2 (20 eyes) deviation occurred in 6 eyes (4 oversized, 2 undersized). In Group 1, capsule tears appeared in 2 eyes and in 1 eye, the procedure had to be converted to extracapsular cataract extraction with anterior vitrectomy. In Group 2, there were no capsule tears.

CONCLUSION

Using 2 different OVDs and placing the high-viscosity OVD centrally led to safe indentation of the anterior lens capsule and reduced the risk for CCC enlargement and capsule tear during surgery.

FINANCIAL DISCLOSURE

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

Femtosecond laser-assisted cataract surgery--current status and future directions

Femtosecond laser-assisted cataract surgery (FLACS) putatively offers several advantages over conventional phacoemulsification. We review the current status of FLACS and discuss the evolution of femtosecond lasers in cataract surgery and the currently available femtosecond laser platforms. We summarize the outcomes of FLACS for corneal wound creation, limbal relaxing incisions, capsulotomy, and lens fragmentation. We discuss surgical planning, preoperative considerations, clinical experiences including the learning curve and postoperative outcomes with FLACS, and also the cost effectiveness of FLACS. We present the intraoperative complications and management of challenging cases where FLACS offers an advantage and also speculate on the future directions with FLACS. Further advancements in laser technology to refine its efficacy, advancement in intraocular lens design to harness the potential benefits of FLACS, and a reduction in cost are needed to establish a clear superiority over conventional phacoemulsification.

Cataract

Cataract is the leading cause of reversible blindness and visual impairment globally. Blindness from cataract is more common in populations with low socioeconomic status and in developing countries than in developed countries. The only treatment for cataract is surgery. Phacoemulsification is the gold standard for cataract surgery in the developed world, whereas manual small incision cataract surgery is used frequently in developing countries. In general, the outcomes of surgery are good and complications, such as endophthalmitis, often can be prevented or have good ouctomes if properly managed. Femtosecond laser-assisted cataract surgery, an advanced technology, can automate several steps; initial data show no superiority of this approach over current techniques, but the results of many large clinical trials are pending. The greatest challenge remains the growing 'backlog' of patients with cataract blindness in the developing world because of lack of access to affordable surgery. Efforts aimed at training additional cataract surgeons in these countries do not keep pace with the increasing demand associated with ageing population demographics. In the absence of strategie that can prevent or delay cataract formation, it is important to focus efforts and resources on developing models for efficient delivery of cataract surgical services in underserved regions. For an illustrated summary of this Primer, visit: http://go.nature.com/eQkKll.

Laser-assisted mini-capsulotomy: a new technique for intumescent white cataracts

PURPOSE

To describe a new two-step femtosecond laser-assisted technique for intumescent white cataracts.

METHODS

In 6 eyes with intumescent white cataracts, a laser-assisted mini-capsulotomy was performed first to release the intralenticular pressure. In the next step, the fluid milky lens material was removed from the anterior chamber before the eyes were re-docked to the laser system and a second larger anterior capsulotomy (4.5-mm diameter) was performed. Finally, the cataractous lens material was removed followed by intraocular lens implantation in the capsular bag.

RESULTS

In all cases, the laser system was able to identify and cut the anterior capsule without complications. Small residual tissue bridges were recognized after laser-assisted mini-capsulotomy in 2 eyes and solved with the dimple-down maneuver. The second, larger capsulotomy demonstrated satisfactory quality and a 360° overlap on the intraocular lens' optic was achieved in all cases.

CONCLUSIONS

This novel technique for intumescent white cataracts using a two-step laser-assisted mini-capsulotomy has the potential to avoid complications.

Femtosecond laser cataract surgery: challenging cases

PURPOSE OF REVIEW

Emerging data in the peer-reviewed literature indicate that femtosecond laser-assisted cataract surgery (LCS) is a well tolerated and effective alternative to conventional phacoemulsification. Initial reports have largely been based on findings from an optimal patient selection. As confidence with the technology has grown, clinical indications have expanded and the benefit of LCS in high-risk patients with complex cataracts is increasingly being considered.

RECENT FINDINGS

We discuss challenging cataract surgery cases, citing the currently available literature alongside experience from over 3000 completed LCS cases at our centre.

SUMMARY

Current experience is limited. However, LCS platforms are continuously evolving and improving. The results collected to date would suggest that the precision and safety offered by LCS may improve outcomes in these challenging cases.

Primary posterior capsular opacification in Indian rural population undergoing cataract surgery for hypermature senile cataract

AIM

To find out the incidence of primary posterior capsular opacification (PCO) in rural patients with a hypermature senile cataract undergoing cataract surgery.

SETTINGS

Tertiary eye care center in central India.

DESIGN

Prospective, observational, noncomparative study.

MATERIALS AND METHODS

Two-hundred eyes of 200 patients presenting with a hypermature cataract underwent manual small incision cataract surgery. A single surgeon performed all surgeries under peribulbar anesthesia. After cortical clean-up, the capsular bag was inflated with viscoelastic. The presence or absence of opacity on the posterior lens capsule and location was noted. Postoperative follow-up was done for visual acuity and need for neodymium-doped yttrium aluminum garnet (ND:YAG) laser capsulotomy.

RESULTS

Primary PCO occurred in 76 eyes (incidence of 38%). It was peripheral in 58 eyes (76.3%) and central in 18 eyes (23.7%). At 6 weeks postoperatively, best corrected visual acuity for eyes with central primary PCO (n = 18) was 0.2-0.3 logMAR and 0-0.2 logMAR for eyes with peripheral primary PCO (n = 58). Best corrected visual acuity at the 6- and 12-month follow-up was 0-0.2 logMAR in both groups. Fibrotic primary PCO was seen in four patients. No predilection for the development of primary PCO to a particular quadrant of posterior capsule was observed. At 1 year postoperatively, eleven (14.5%) patients required ND:YAG laser capsulotomy, six (7.90%) of whom underwent ND:YAG laser capsulotomy at the 6-month follow-up. Seven patients with central primary PCO and four patients with peripheral primary PCO required ND:YAG laser capsulotomy.

CONCLUSION

A high incidence of primary PCO was noted in rural patients with a hypermature senile cataract undergoing cataract surgery. No serious intraoperative complications were noted. Visual outcome at 1-year follow-up was satisfactory. Need for early ND:YAG laser posterior capsulotomy should be explained to these patients before cataract surgery. No post ND:YAG capsulotomy complications were noted in any patient.

Results of coaxial phacoemulsification through a 1.8-mm microincision in hard cataracts

BACKGROUND AND OBJECTIVE

To assess the results of coaxial phacoemulsification through 1.8-mm coaxial microincision cataract surgery (C-MICS) phacoemulsification with foldable intraocular lens implantation in eyes with hard cataracts in comparison to eyes with soft cataracts.

PATIENTS AND METHODS

Group 1 consisted of 40 eyes of 40 patients with hard cataracts (grade ≥ 4, Lens Opacities Classification System III scale) and group 2 consisted of 45 eyes of 45 patients with non-mature cataracts (grade ≤ 2, Lens Opacities Classification System III scale). All surgeries were performed by two experienced surgeons under topical and intracameral anesthesia. Examinations were performed preoperatively and 1 month after the surgery. Examined parameters included distance-corrected visual acuity (DCVA), autorefractometry, keratometry, tonometry, endothelial cell counts, and biomicroscopy of the anterior and posterior segment. Surgically induced astigmatism was calculated with vector analysis.

RESULTS

Mean DCVA was 0.16 ± 0.16 preoperatively and 0.92 ± 0.21 postoperatively in group 1 (P < .05) and 0.62 ± 0.18 preoperatively and 0.97 ± 0.08 postoperatively in group 2 (P < .05). Mean surgically induced astigmatism was 0.48 ± 0.44 in group 1 and 0.53 ± 0.38 in group 2 (P > .05). Mean endothelial cell loss was 11.37% ± 12.87% in group 1 and 2.87% ± 9.66% in group 2 (P < .05).

CONCLUSION

Although density of cataract has an unfavorable influence on early postoperative corneal endothelial cell loss, it did not significantly influence final DCVA and surgically induced astigmatism. C-MICS is a safe and effective method of treatment of cataracts, including cataracts with hard nuclei, and usually leads to good functional outcomes.

Phacoemulsification versus manual small-incision cataract surgery for white cataract

PURPOSE

To compare the safety and efficacy of phacoemulsification and manual small-incision cataract surgery (SICS) to treat white cataracts in southern India.

SETTING

Aravind Eye Hospital, Pondicherry, India.

DESIGN

Randomized prospective study.

METHODS

Consecutive patients with white cataract were randomly assigned to have phacoemulsification or manual SICS by 1 of 3 surgeons experienced in both techniques. Surgical complications, operative time, uncorrected (UDVA) and corrected (CDVA) distance visual acuities, and surgically induced astigmatism were compared.

RESULTS

On the first postoperative day, the UDVA was comparable in the 2 groups (P = .805) and the manual SICS group had less corneal edema (10.2%) than the phacoemulsification group (18.7%) (P = .047). At 6 weeks, the UDVA was 20/60 or better in 99 patients (87.6%) in the phacoemulsification group and 96 patients (82.0%) in the manual SICS group (P = .10) and the CDVA was 20/60 or better in 112 (99.0%) and 115 (98.2%), respectively (P = .59). The mean time was statistically significantly shorter in the manual SICS group (8.8 minutes ± 3.4 [SD]) than in the phacoemulsification group (12.2 ± 4.6 minutes) (P<.001). Posterior capsule rupture occurred in 3 eyes (2.2%) in the phacoemulsification group and 2 eyes (1.4%) in the manual SICS group (P = .681).

CONCLUSIONS

Both techniques achieved excellent visual outcomes with low complication rates. Because manual SICS is significantly faster, less expensive, and less technology-dependent than phacoemulsification, it may be a more appropriate technique in eyes with mature cataract in the developing world.

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.

[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.

[Phacoemulsification in eyes with white cataracts: results and complications]

PURPOSE

To compare visual acuity and complications in phacoemulsification in eyes with white cataract and in eyes with immature senile cataract.

PATIENTS AND METHODS

This was a prospective study on 36 eyes in 34 patients with white cataract (group 1) and 36 eyes in 36 patients with immature senile cataract (group 2).

RESULTS

In group 1, mean preoperative visual acuity was 1/100 and mean postoperative visual acuity was 5/10 at 1 month. Posterior capsule tears occurred in four eyes (11%). In group 2, mean preoperative visual acuity was 2/10 and mean postoperative visual acuity was 7/10 at 1 month. No posterior capsule tear was observed. The preoperative visual acuity was significantly lower in group 1 (p=1.8x10(-14)). Postoperative visual acuities were not significantly different between the two groups (p=0.07). The increase in visual acuity was significantly higher in group 1 (p=2.2x10(-11)).

DISCUSSION

Our study shows that white cataract is not a risk factor of poor postoperative visual acuity and the increase in visual acuity is greater in the white cataract group than in the immature cataract group.

CONCLUSION

The results of phacoemulsification in white cataracts are satisfactory in spite of a high rate of posterior capsule rupture in our study.

Safety and Efficacy of Micro-Incisional Cataract Surgery with Bimanual Phacoemulsification for White Mature Cataract

BACKGROUND

To evaluate the safety and efficacy of micro-incisional cataract surgery (MICS) with bimanual phacoemulsification for the management of white mature cataract.

METHODS

Twenty-five eyes in 25 patients with mature cataract were prospectively recruited to undergo MICS with bimanual phacoemulsification. Serial changes in best-corrected visual acuity (BCVA), central corneal thickness (CCT) and endothelial cell density (ECD) were compared using the Wilcoxon signed-rank test.

RESULTS

MICS was successfully performed in 24 (96%) of the 25 eyes, with 1 eye requiring conversion to extracapsular cataract extraction due to radial tear during continuous curvilinear capsulorhexis. The median preoperative BCVA was hand movement. On day 1 postoperatively, the median BCVA improved to 0.6 (p < 0.001 compared with baseline). All patients had BCVA of 0.6 or better at 3 months after surgery (p < 0.001 compared with baseline). The mean increase in CCT at day 1 and week 1 postoperatively was 11.5 and 7.1%, respectively. The change in mean CCT was no longer significant at month 3 postoperatively (p = 0.82). The mean reduction in ECD at 3 months postoperatively was 7.8% (p = 0.037). None of the patients developed any postoperative complications.

CONCLUSIONS

MICS with bimanual phacoemulsification appeared to be a promising alterative for the management of white mature cataract.

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 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.

Comparing the efficacy and safety of phacoemulsification in white mature and other types of senile cataracts

AIM

To compare the intraoperative difficulty and postoperative outcome in patients who have white mature cataract in one eye and other types of senile cataract in the other eye undergoing clear corneal phacoemulsification and foldable intraocular lens implantation.

METHODS

82 patients who had white mature cataract in one eye, posterior subcapsular, cortical, nuclear, or mixed type cataract in the other eye were enrolled in this prospective study. Postoperative outcomes, intraoperative difficulties related to capsulorhexis, and phacoemulsification were analysed between the two groups of eyes. Postoperative examinations were done at 1 day, 1 week, 1 and 3 months.

RESULTS

Postoperative visual acuity, central corneal thickness, intraocular pressure, and rate of posterior capsule rupture were not significantly different between the two group of eyes (p>0.05). Mean effective phaco time, frequency of postoperative corneal oedema and posterior capsular plaque were found to be significantly higher in the mature cataract group (p<0.05).

CONCLUSIONS

A one stage, 5 mm continuous capsulorhexis was achieved using trypan blue and generous amounts of retentive viscoelastic agent in eyes with white mature cataract. Intraoperative difficulties and postoperative outcome of clear corneal incision phacoemulsification surgery and foldable intraocular lens implantation were similar in white mature and other types of senile cataract. Topical anaesthesia in phacoemulsification of eyes with white mature cataract is safe and well tolerated.

A histological analysis of lens capsules stained with trypan blue for capsulorrhexis in phacoemulsification cataract surgery

PURPOSE

Staining of anterior lens capsules with dye to facilitate completion of continuous curvilinear capsulorrhexis is now being used more frequently in phacoemulsification of white and mature cataracts with poor red reflexes. This study examined the histological characteristics of anterior lens capsules stained with trypan blue. The layer(s) of the lens capsule that stained with dye and the extent of accumulation of dye in these layers of the lens capsule were determined. To the best of our knowledge this has not been described before.

METHODS

A series of 10 stained lens capsules were analysed histologically. The dye used in this study consisted of a standard sterile, noninflammatory, nonpyrogenic, 2 ml solution containing 0.6 mg/ml of trypan blue. Following capsulorrhexis, samples were sent to the laboratory for histological analysis. Frozen sections (8 microm) were prepared and examined with the light microscope. All 10 capsules were cut by frozen section to preserve trypan blue staining (which would be leached by processing) and then subjected to immunohistochemistry for collagen IV. Immunohistochemical analysis using markers for type IV collagen were done on formalin-fixed specimens for morphological comparison with the frozen sections. A counterstain highlighted the epithelium.

RESULTS

Continuous curvilinear capsulorrhexis was successfully and easily completed in all cases without any complications. Frozen section analysis using light microscopy demonstrated accumulation of trypan blue dye in the basement membrane of the lens capsule. Staining was concentrated in the portion of the membrane adjacent to the lens epithelium. The lens epithelium could not be clearly identified on the frozen sections. Consequently, immunohistochemical analysis with markers for type IV collagen was performed. A counterstain highlighted the epithelium. This confirmed that the layer staining with trypan blue was the basement membrane, a consistent feature on all the specimens.

CONCLUSION

Trypan blue selectively stains the basement membrane of the anterior lens capsule. There is a concentration of dye in the basement membrane adjacent to the lens epithelial cell layer. The lens cortex does not appear clinically to stain with trypan blue. This enables surgeons to distinguish the lens capsule from the cortex and provides sufficient contrast for successful completion of continuous curvilinear capsulorrhexis during cataract surgery.

Trypan blue as an adjunct for safe phacoemulsification in eyes with white cataract

PURPOSE

To assess the feasibility, risks, and postoperative outcomes of phacoemulsification with posterior chamber intraocular lens (PC IOL) implantation in cases of white cataract with the use of trypan blue as an adjunct for performing continuous curvilinear capsulorhexis (CCC) in the absence of a red reflex.

SETTING

Dr. Agarwal's Eye Hospital, Chennai, India.

METHODS

This prospective study comprised 52 eyes of 52 patients with white cataract that had phacoemulsification through a clear corneal temporal incision with PC IOL implantation. In all the cases, trypan blue was used under air to stain the anterior lens capsule and the karate-chop technique was used to emulsify the nucleus. The mean follow-up was 192.2 days.

RESULTS

Trypan blue adequately stained the anterior lens capsule in all cases. The CCC was completed uneventfully in 96.15% eyes; 3.85% of cases had to be converted to a conventional extraction technique because of the loss of the CCC. The mean phacoemulsification time was 2.2 minutes. Intraocular complications included incomplete capsulorhexis (3.85%) and pupillary miosis (3.80%). Postoperatively, 3 eyes (5.77%) had corneal edema (striate keratopathy) and 1 eye (1.9%) had fibrin in the anterior chamber. Five eyes (9.61%) had more than 2+ cells and flare at 2 weeks. All responded well to intensive topical and subconjunctival steroids. There were no cases of endophthalmitis. The mean central endothelial cell loss, measured in 37 eyes, was 8.5%. Of the 4 eyes (7.69%) that had increased intraocular pressure (IOP) postoperatively, all responded well to medications and the IOP was normal by the second postoperative week. Fifty eyes (96.16%) had a final best corrected visual acuity of 20/30 or better. In 2 cases, the final visual acuity was worse than 20/200 because of preexisting posterior segment pathology.

CONCLUSION

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

Bimanual Sinskey hook technique to enlarge a preexisting capsulorhexis

We describe a technique of enlarging a small primary capsulorhexis. Two Sinskey hooks are introduced through the side ports. One hook is placed above the anterior capsulorhexis margin with its tip pointing down, and the other is placed beneath the anterior capsulorhexis margin with its tip pointing up. A small nick is made between the tips of the 2 hooks, and the capsulorhexis is extended with a Utrata capsulorhexis forceps. This technique does not require additional instrumentation, impart zonular stress, or disturb wound architecture or integrity.

Indocyanine green staining in traumatic cataract

We report the first case of indocyanine green (ICG) being used in an eye with an anterior capsule that was not completely intact. We found that ICG seems to have a selective affinity for the anterior capsule over cortical lens material. The patient had a corneal perforation with a wire and developed endophthalmitis requiring pars plana vitrectomy with intravitreal antibiotics. He subsequently developed a white traumatic cataract with an anterior capsule tear. Five months after the injury, he had cataract extraction. Indocyanine green was used to better visualize the anterior capsule before capsulotomy. The anterior capsule stained green, but the cortical material exposed to ICG did not stain.

Gentian violet solution for staining the anterior capsule

PURPOSE

To evaluate the histopathological changes after injecting gentian violet solution into the anterior chamber of rats and to describe a technique that uses gentian violet to allow a clear view of the anterior capsule during continuous curvilinear capsulorhexis (CCC) in human eyes with white mature cataract.

SETTING

Department of Ophthalmology, University of Dicle, Diyarbakir, Turkey.

METHODS

In this masked, experimental study (first stage), 0.05 mL of gentian violet 0.01% or 0.001% solution or balanced salt solution (BSS) (control group) was injected into the anterior chamber of 30 eyes of 30 Wistar albino rats. One, 24, and 48 hours after injection, 4 eyes in each group and 2 eyes in the control group were enucleated, and histopathological examination was performed. In the second stage, these solutions were used for staining the anterior capsule in the 18 human eyes with white mature cataract. The success rate of CCC and intraoperative and postoperative complications were evaluated.

RESULTS

Histopathological examination revealed no pathology in any group. A CCC was completed in all cases. No intraoperative or postoperative complications were observed in human eyes except mild corneal edema and mild inflammatory reaction in the anterior chamber that improved within 1 week. Mean follow-up was 3.4 months. Visualization of the anterior capsule was better with gentian violet 0.01% solution.

CONCLUSIONS

Gentian violet solutions at 0.01% and 0.001% concentrations had no evident toxic effect that caused significant histopathological changes. The staining technique was practical and helped the surgeon visualize the anterior capsule. However, gentian violet may have adverse effects that lead to corneal edema.

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

PURPOSE

To evaluate anterior capsule staining using 3 dyes to perform continuous curvilinear capsulorhexis (CCC) in postmortem human eyes with advanced/white cataract.

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

In experimental closed-system surgery, CCC was performed in 12 postmortem human eyes with cataract after the anterior capsule was stained with 3 capsule dyes (fluorescein sodium 2%, indocyanine green [ICG] 0.5%, and trypan blue 0.1%). Two commonly used techniques for capsule staining were also compared: staining within an air bubble and intracameral subcapsular injection of dye.

RESULTS

In all globes, CCC was uneventful using the 3 dyes and with both techniques. With the intracameral subcapsular injection, the dye remained trapped in the subcapsular space in contact with the posterior surface of the anterior capsule, allowing enough time to perform any maneuver. The staining provided by ICG, at the concentration used, was slightly superior to that of the other dyes. Leakage of fluorescein sodium into the vitreous cavity was seen using the Miyake-Apple posterior video/photographic technique.

CONCLUSION

Intracameral subcapsular injection of ICG allowed the easiest recognition of the capsular flap by staining the posterior surface of the anterior capsule and without leaking into the vitreous cavity.

Dye-enhanced cataract surgery. Part 2: learning critical steps of phacoemulsification

PURPOSE

To use capsule dyes to enhance visualization to learn and perform various critical steps of the phacoemulsification procedure in a laboratory setting using postmortem human eyes.

SETTING

Center for Research on Ocular Therapeutics and Biodevices, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA.

METHODS

Indocyanine green 0.5% (ICG) and trypan blue 0.1% were used to enhance visualization for performing critical steps of phacoemulsification in 8 human eyes obtained postmortem. All eyes were prepared according to the Miyake-Apple posterior video technique. After a continuous curvilinear capsulorhexis (CCC) was made, the dyes were used to enhance visualization for hydrodissection, hydrodelineation, and various maneuvers for nuclear emulsification and cortical cleanup. In 8 eyes, all the aforementioned steps were performed without using dye (control group).

RESULTS

Both dyes helped enhance visualization during the critical steps of phacoemulsification. The use of a dye solution instead of balanced salt solution (BSS) for hydrodissection/delineation helped localize the complete plane of cleavage between the capsule and cortex and the nucleus-epinucleus complex. During various nuclear sculpting maneuvers, the use of dye helped visualization of the position of the phaco tip and its relation to the posterior capsule. It also helped localize remaining cortical fibers, facilitating complete cleaning of the capsular bag.

CONCLUSIONS

Dye-enhanced cataract surgery was useful in learning various critical steps of phacoemulsification in a wet laboratory setting.

Ultrasonographic classification and phacoemulsification of white senile cataracts

OBJECTIVE

To classify the white senile cataracts and report the results of phacoemulsification of white cataracts.

DESIGN

Prospective, noncomparative case series.

PARTICIPANTS

One hundred eyes were included.

INTERVENTION

White cataracts were examined biomicroscopically before surgery, and their acoustic structure was analyzed with standardized A-scan echography. White cataract surgery was performed with phacoemulsification via a superior temporal near-limbus corneal approach using a bimanual divide-and-conquer or stop-and-chop technique. Patients were followed after surgery for a period of 9 months.

MAIN OUTCOMES MEASURES

The A-scan acoustic structure of white cataracts; successful accomplishment of capsulorrhexis; mean phacoemulsification time, power, and energy; intraoperative and postoperative complications of phacoemulsification; and visual acuity at 9 months after surgery.

RESULTS

White senile cataracts were categorized into three different types. Type I included intumescent, white cataracts with cortex liquefaction and high internal acoustic reflections (44 eyes), type II included white cataracts with voluminous nuclei, little amount of whitish solid cortex, and low internal acoustic reflections (49 eyes), and type III included white cataracts with fibrosed anterior capsule and low internal echospikes (7 eyes). Circular capsulorrhexis was completed in 79 eyes and was significantly less successful in eyes with type I intumescent, white cataracts compared with type II white cataracts (P = 0.0034). Mean phacoemulsification time and energy were higher in type II and type III white cataracts. Posterior capsule rupture occurred in ten eyes, and three of these eyes were complicated by vitreous loss. In 95 eyes, the posterior chamber lens was implanted in the capsular bag and in five eyes in the sulcus. After surgery, a transient corneal edema developed in 31 eyes. At the final 6-month examination, the mean postoperative visual acuity was 20/30.

CONCLUSION

Current phacoemulsification techniques can safely manage eyes with senile white cataracts. The increased risk of difficulty with continuous capsulorrhexis in type-I and type-III white cataracts and the substantial nuclear hardness in type-II and mainly type-III white cataracts would suggest that current phacoemulsification techniques might not be as successful in these patients as they are in ordinary earlier cataracts.