Femtosecond Laser-assisted Cataract Surgery in Patients With Marfan Syndrome and Subluxated Lens

Femtosecond laser-assisted cataract surgery for complex cataracts - A review

Since its inception in 2009, femtosecond laser-assisted cataract surgery (FLACS) has become an alternative to conventional phacoemulsification cataract surgery (CPCS). Clinical studies were unable to demonstrate superior visual outcomes, but revealed reduced endothelial cell loss. More recently, the cost-effectiveness of FLACS over CPCS in routine cataract surgeries has been challenged. However, the unique abilities of FLACS to customize anterior capsulotomies precisely, soften and fragment the nucleus without capsular bag stress, and create corneal incisions may have special utility in complex cataract and less-common scenarios. In this article, we review the unique role of FLACS in complex cataract surgeries and how it could play a role to improve the safety and predictability of nonroutine cataract surgery.

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.

Two-Year Follow-Up of Clinical Efficacy of Femtosecond Laser, Modified Capsular Tension Ring, and Iris Hook-Assisted Surgical Treatment of Lens Subluxation in Patients with Elevated Intraocular Pressure

Purpose

To evaluate the outcomes of femtosecond laser, modified capsular tension ring, and iris hook-assisted surgical treatment of lens subluxation in patients with elevated intraocular pressure (IOP).

Methods

Fifteen patients with lens subluxation and elevated IOP were enrolled in this study. All patients underwent femtosecond-laser-assisted cataract surgery/phacoemulsification/intraocular lens implantation/modified capsular tension ring (MCTR) implantation with iris hook assistance. Uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), IOP, number of glaucoma medication complications, endothelial cell density (ECD), and tilt of the lens were recorded before and after surgery. All patients were observed for 24 months postoperatively.

Results

UCVA and BCVA increased significantly at 1 month, 6 months, 12 months, and 24 months, compared with preoperative UCVA and BCVA (P < 0.001). IOP significantly decreased at 1 month, 3 months, 6 months, 12 months, and 24 months, compared with preoperative IOP (P < 0.001). 3 patients received glaucoma medications to control IOP after surgery. All medications were discontinued at 3 months postoperatively. Conjunctival redness or hemorrhage was observed in 11 patients (73.3%); transient corneal edema was observed in 3 patients (20.0%); and posterior capsule opacification occurred in 1 patient (6.67%). The ECD and tilt of the lens are within an acceptable range.

Conclusion

The combined use of a femtosecond laser, MCTR, and iris hooks is an effective and safe method for treating patients with lens subluxation and elevated IOP.

Limited pars-plana vitrectomy for optimizing surgical outcome in subluxated cataracts undergoing femtosecond laser-assisted cataract surgery

We propose a technique for combined femto laser-assisted cataract surgery (FLACS) and limited vitrectomy from the pars-plana site for optimization of surgical results in subluxated cataracts. FLACS creates a free-floating, customised capsulotomy, minimizes stress on compromised zonules, and prechops the nucleus, effectively reducing the ultrasonic power as well as the forces required to chop the nucleus. The area of zonular dehiscence creates a direct communication between the irrigation fluid and the anterior vitreous, leading to its hydration. Trans-limbal vitrectomy creates a continuum between the liquefied vitreous and the main wound, leading to further vitreous loss, and exaggeration of the zonular weakness, while pars-plana vitrectomy avoids this by cutting the liquefied vitreous, near its attachment, thereby preventing further hydration and causing lesser stress to the zonules. A combination of these procedures, along with a capsule support device, gives favorable surgical outcomes in moderate to severe subluxations.

Cataract: Advances in surgery and whether surgery remains the only treatment in future

Background

Cataract is the world's leading eye disease that causes blindness. The prevalence of cataract aged 40 years and older is approximately 11.8%-18.8%. Currently, surgery is the only way to treat cataracts.

Main Text

From early intracapsular cataract extraction to extracapsular cataract extraction, to current phacoemulsification cataract surgery, the incision ranges from 12 to 3 ​mm, and sometimes to even 1.8 ​mm or less, and the revolution in cataract surgery is ongoing. Cataract surgery has transformed from vision recovery to refractive surgery, leading to the era of refractive cataract surgery, and premium intraocular lenses (IOLs) such as toric IOLs, multifocal IOLs, and extended depth-of-focus IOLs are being increasingly used to meet the individual needs of patients. With its advantages of providing better visual acuity and causing fewer complications, phacoemulsification is currently the mainstream cataract surgery technique worldwide. However, patient expectations for the safety and accuracy of the operation are continually increasing. Femtosecond laser-assisted cataract surgery (FLACS) has entered the public's field of vision. FLACS is a combination of new laser technology and artificial intelligence to replace fine manual clear corneal incision, capsulorhexis, and nuclear pre-fragmentation, providing new alternative technologies for patients and ophthalmologists. As FLACS matures, it is being increasingly applied in complex cases; however, some think it is not cost-effective. Although more than 26 million cataract surgeries are performed each year, there is still a gap in the prevalence of cataracts, especially in developing countries. Although cataract surgery is a nearly ideal procedure and complications are manageable, both patients and doctors dream of using drugs to cure cataracts. Is surgery really the only way to treat cataracts in the future? It has been verified by animal experiments that lanosterol therapy in rabbits and dogs could make cataract severity alleviated and lens transparency partially recovered. Although there is still much to learn about cataract reversal, this groundbreaking work provided a new strategy for the prevention and treatment of cataracts.

Conclusions

Although cataract surgery is nearly ideal, it is still insufficient, we expect the prospects for cataract drugs to be bright.

[Surgical treatment of hypermature cataract in patients with lens subluxation and small pupil]

Studying the possibilities of hybrid (femtosecond laser-assisted) phacoemulsification in complicated situations is a relevant problem in cataract surgery.

PURPOSE

To develop a technique for hybrid (femtosecond laser-assisted) phacoemulsification in patients with a combination of hypermature cataract, small pupil and lens subluxation.

MATERIAL AND METHODS

Hybrid (femtosecond laser-assisted) phacoemulsification of hypermature cataracts was performed in 36 patients (36 eyes) aged 63 to 78 years with grade I-II lens subluxation in combination with small pupil. The initial circular femtolaser capsulotomy was performed within the small pupil using the VICTUS system (Technolas Perfect Vision, Germany). After dilating the pupil with retractor hooks, the capsulorhexis was manually expanded to the required diameter.

RESULTS

In all cases, the resulting capsulorhexis had a regular round shape with a smooth edge, without radial ruptures. This made it possible to apply modern methods of fixation and centration of the capsular bag in case of lens subluxation and to perform intracapsular implantation of an intraocular lens (IOL). Complete intracapsular fixation of the IOL with optics edge fully covered by the edge of the capsulorhexis in the postoperative period was achieved in 34 (94.4%) cases. In 2 (5.6%) cases in the postoperative period, the edge of the capsulorhexis exceeded the edge of the IOL optics. The loss of corneal endothelial cells 3 months after surgery was 8.8±1.9%.

CONCLUSION

The use of the proposed combined technique of capsulorhexis made it possible to perform the most physiologically appropriate intracapsular IOL implantation in all patients with hypermature cataract, small pupil and lens subluxation.

[Femtosecond laser-assisted phacoemulsification of hypermature cataract in patients with lens subluxation]

Studying the modern capabilities of femtosecond laser in the treatment of complicated cataracts is a topical problem in cataract surgery.

PURPOSE

To develop a technique for femtosecond laser-assisted phacoemulsification of hypermature cataract in patients with degree I-II lens subluxation.

MATERIAL AND METHODS

Phacoemulsification of hypermature cataract with comorbid lens subluxation was performed in 78 patients (78 eyes) divided into two groups. In the 1st group (45 eyes), capsulorhexis was performed using a femtosecond laser. Patients of the 2nd group (33 eyes) underwent manual capsulorhexis. The study assessed the possible frequency of using modern methods of capsular bag fixation and complete all-in-the-bag intraocular lens (IOL) implantation, as well as the number of various types of intraoperative capsular bag ruptures.

RESULTS

In all patients of the 1st group, capsulorhexis of the correct round shape and the required diameter was achieved, allowing the use of modern methods of fixation and centering of the capsular bag. Insignificant tear of the edge of the capsulorhexis after IOL implantation was detected only in 1 (2.2%) patient. Vitreous prolapse was noted in 1 (2.2%) case. In the 2nd group, manual technique resulted in oval capsulorhexis with a smooth edge, allowing the use of modern methods of fixation of the capsular bag only in 7 (21.2%) cases. Vitreous prolapse was noted in 4 (12.1%) cases. The complete in-the-bag IOL implantation was possible in 44 (97.8%) cases in the 1st group and only in 7 (21.2%) in the 2nd group.

CONCLUSION

The use of femtosecond laser in patients with hypermature cataract and lens subluxation allows achieving capsulorhexis of ideally round shape with a smooth edge. This creates the necessary conditions for the use of modern methods of fixation of the capsular bag and provides the possibility of complete all-in-the-bag IOL implantation.

Suction Break During Femtosecond Laser-Assisted Cataract Surgery and Misplaced Laser Beam Delivery to the Corneal Layers

A 68-year-old man with senile cataract underwent femtosecond laser-assisted cataract surgery (FLACS) in his left eye. Only anterior capsulotomy and lens fragmentation were planned with a femtosecond laser. Docking of the patient interface and anterior capsulotomy were completed without any complications. During the lens fragmentation process, the patient could not resist the temptation to squeeze his eyes shut, which caused excessive pressure from the eyelids. As the procedure proceeded, a bubble was formed at the edge of the patient interface and became increasingly larger. In addition, wrinkles in the conjunctiva were observed. As the lens fragmentation was approaching the final stage, the surgeon was reluctant to release the foot pedal to stop the laser emission. Finally, the patient interface lost adhesion to the cornea. Owing to the high repetition rate of the laser, the laser beam slipped into the corneal layers. Under an operating microscope, a grid-pattern laser beam trace was observed in the peripheral part of the cornea. As posterior capsule rupture occurred during the lens removal process, IOL insertion was no longer a suitable option. Therefore, scleral fixation of the implanted intraocular lens was performed without any unexpected events. One year postoperatively, the laser beam trace in the corneal layers could still be identified by slit-lamp examination. Nonetheless, since the laser beam trace was limited to the peripheral part of the cornea, and there was no damage to the central cornea, the visual acuity was 20/20. FLACS has significant benefits, especially in challenging cases of cataract surgery, and has well-established built-in safeguards for complications. However, this case study indicates the possibility of a suction break during laser emission and the preoperative risk factors. It demonstrates that recognizing the signs of suction break is necessary to avoid misplacement of the laser beam on the corneal layers.

Comparison of Femtosecond Laser-Assisted Cataract Surgery and Conventional Phacoemulsification in Shallow Anterior Chambers and Glaucoma

Purpose

To compare femtosecond laser-assisted cataract surgery (FLACS) versus conventional phacoemulsification in shallow anterior chamber cataract patients with glaucoma or zonulysis.

Methods

This was a single-center retrospective review of cataract surgeries in shallow anterior chamber and glaucoma patients between January 2016 and December 2018 in which a LenSx femtosecond laser was used. The outcome measures included pre- and postoperative uncorrected and corrected distance visual acuity (UDVA and CDVA), intraocular pressure (IOP), endothelial cell density (ECD), endothelial cell loss (ECL), and object scatter index (OSI).

Results

One hundred and six eyes of 106 patients with a mean anterior chamber depth of 1.54 ± 0.51 mm were included in this study. Among them, 26 (23.2%) had zonulysis and 18 eyes had capsular tension ring implantation in general. The percentage of capsular tension ring implantation was statistically significantly lower in the FLACS group (P = 0.027). The UDVA, CDVA, ECD, and IOP were not statistically significant between the two groups at all time points. The postoperative ECL and OSI of the FLACS group was better than those of the conventional group (P < 0.01).

Conclusions

FLACS can reduce ECL and improve visual quality compared to the conventional phacoemulsification in shallow anterior chamber patients. Also, it has the trend of reducing the use of capsular tension rings in subluxated cataracts. It is an ideal choice for patients with complicated cataract such as with shallow anterior chambers, glaucoma, and zonulysis.

Femtosecond laser-assisted cataract surgery in a spherophakic lens: An unusual case report

RATIONALE

Spherophakia is a rare diagnosis which is often associated with a shallow anterior chamber, angle-closure glaucoma, lens subluxation, and lenticular myopia. When cataracts occur with subluxation of the lens, vision is often markedly affected. This often presents surgeons with a unique challenge of maintaining good visual outcomes while minimizing potential complications.

PATIENT CONCERNS

A 48-year-old female was referred for ophthalmological assessment due to decreased vision in the left eye. In the left eye, the best-corrected visual acuity at distance was 20/125 with manifest refraction of -6.5D + (-0.75) D × 118°. The slit lamp examination showed iridodonesis and a significant nuclear cataract (C3N3) with tremor in the left eye. After pupil dilation, a subluxated lens, weak zonules, and "fake golden ring" within the lens was noted.

DIAGNOSIS

Due to the patient's symptoms, examination results, she was diagnosed with cataract, subluxation of the lens and spherophakia in left eye.

INTERVENTIONS

The patient underwent an uneventful femtosecond laser-assisted cataract surgery (Alcon Fort Worth, TX). The laser was able to perform a circular free-floating anterior capsulotomy and easy lens fragmentation.

OUTCOMES

There were no postoperative complications. At 3 months postoperatively, the uncorrected visual acuity was 20/25, and the manifest refraction was -0.25 D - 0.75 D × 148° with the corrected distance visual acuity of 20/16.

LESSONS

Femtosecond laser-assisted cataract surgery is an effective approach for cataract surgery in patients with subluxated and spherophakic lenses, with the benefits of causing minimal further zonular damage and easy lens fragmentation.

[Application of femtosecond laser technology in the management of subluxated lens]

OBJECTIVE

To evaluate the application of femtosecond laser technology in the management of subluxated lens.

METHODS

We retrospectively analyzed the data of the patients with subluxated lens undergoing femtosecond laser- assisted surgery at the Cataract Center of Guangzhou Aier Eye Hospital between March, 2017 and May, 2019. The LenSx femtosecond laser-assisted cataract surgery system was used to perform capsulotomy and lens fragmentation. According to the patients' eye condition, anterior vitrectomy was performed and capsular retractors was used. After phacoemulsification, I/A and insertion of the tension rings, the intraocular lens (IOL) was implanted into the capsular bag. The perioperative data, complications, visual acuity and intraocular pressure after the operation were recorded, and the stability of the capsular bag and IOLs were assessed.

RESULTS

We analyzed the data of 25 cases (29 eyes) of subluxated lens, including 16 (16 eyes; 55.17%) as the result of traumatic lens subluxation, 5 (9 eyes; 31.03%) of Mafan syndromes, 1 case (1 eye; 3.45%) of high myopia and 3 cases (3 eyes; 10.34%) of unknown causes. Thirteen 13 eyes (44.83%) showed mild subluxation, 7 (24.14%) had moderate subluxation, and 9 (31.03%) had severe subluxation. Femtosecond laser- assisted capsulorhexis, lens fragmentation and phacoemulsification were successfully completed for 29 eyes, of which 28 eyes (96.55%) retained the complete capsular bag and with successful implantation of the capsular tension devices and IOLs. Nine eyes (31.03%) were treated with anterior segment vitrectomy; iris hooks were used for 2 eyes (6.90%) and capsular bag hooks for 9 eyes (31.03%). The best corrected visual acuity was significantly improved in 29 eyes after operation (P &lt; 0.05). At 1 month after the surgery, 26 eyes (89.66%) showed stably centered IOLs, 2 eyes (6.90%) showed slight tilt of the IOLs, and 3 eyes (10.34%) had anterior capsular contraction. The intraoperative complications included subconjunctival hemorrhage (75.87%), incomplete capsulotomy (17.24%) and contracted pupils (13.79%).

CONCLUSIONS

The application of femtosecond laser assisted technology enhances the surgical safety and effectiveness for subluxated lens, facilitates the choice of individualized surgical options, and promotes maximum recovery of the patients' visual function.

[Femtosecond laser-assisted cataract surgery and conventional phacoemulsification cataract surgery in patients with lens subluxation]

PURPOSE

To analyze the results of femtosecond laser-assisted cataract surgery (FLACS) and conventional phacoemulsification cataract surgery (CPCS) in patients with 1-2 degree lens subluxation.

MATERIAL AND METHODS

The follow-up involved 86 patients (89 eyes). The 1^st group comprised 34 patients (35 eyes) that underwent FLACS; the 2^nd group included 52 patients (54 eyes) who underwent CPCS.

RESULTS

At day four of the follow-up central corneal thickness was significantly lower after FLACS (p_m-u=0.024), but the difference did not remain statistically reliable by 1.5 months after the surgery. At discharge day and 4 months after the surgery uncorrected visual acuity (UCVA) after FLACS reliably exceeded UCVA of the 2^nd group patients (p_m-u=0.00) with mean UCVA being 0.61±0.29 and 0.42±0.25 respectively. Internal higher order aberrations (HOA) in 5.0 mm zone in the 1^st group decreased by 4 times and amounted to 0.236±0.06 μm, in the 2^nd group increased by 4.1 times and was 4.606±8.16 μm; the difference between the groups was statistically significant (p_m-u<0.001). Mean endothelial cells density after FLACS was 2551.91±321.55 cells/mm², after CPCS - 2352.35±436.68 cells/mm² (p_m-u<0.005). Complications after FLACS included 2 cases (5.71%) of posterior capsular rupture and 1 case (2.8%) of post-op corneal edema; patients after CPCS had 6 (11.1%) and 12 (22.2%) complication cases respectively.

CONCLUSION

FLACS is the safer and more effective surgery choice for patients with 1-2 degree lens subluxation in comparison with CPCS; it decreases the risk of possible complications and provides faster postoperative rehabilitation.

Femtosecond laser-assisted cataract surgery in patients with zonular weakness

Purpose

To present the clinical value of femtosecond laser assisted cataract surgery (FLACS) in eyes with compromised zonules.

Observations

We present two cases of femtosecond laser assisted cataract surgery (FLACS) in eyes with compromised zonules. Three eyes from two patients with zonular weakness and cataract underwent FLACS (Alcon LenSx Lasers Inc., Aliso Viejo, CA). One patient underwent bilateral FLACS in the setting of spherophakia with zonular weakness. The other patient had Marfan's syndrome with associated ectopia lentis. Laser assisted capsulotomy was achieved in all eyes. One eye had vitreous prolapse during surgery and required an iris-sutured lens. All eyes had a postoperative corrected distance visual acuity of 20/25 or better.

Conclusions and Importance

FLACS is a safe and effective alternative to conventional phacoemulsification cataract surgery in patients with zonular weakness.

The advantages of femtosecond laser-assisted cataract surgery for zonulopathy

Zonulopathy is a major concern if found during cataract surgery as it can cause further complications. Such complications may occur during continuous curvilinear capsulorhexis (CCC), lens fragmentation and intraocular lens (IOL) implantation. Femtosecond laser-assisted cataract surgery (FLACS) devices, such as the LenSX (Alcon Laboratories) are advantageous because they can detect the area and largest point of zonulopathy via anterior segment optical coherent tomography (AS-OCT) before the manual part of the procedure. CCC and lens fragmentation can also minimize further zonular stress. A symmetrical CCC is ideal for IOL implantation in the sulcus with optic capture. In the present study, we did not detect significant zonular dehiscence preoperatively in either of the eyes of our 68-year-old patient when using AS-OCT (CASIA2 Tomey). However, LenSx AS-OCT revealed zonular dehiscence in both eyes, perioperatively. We created CCC and lens fragmentation without causing stress to the zonules. In the subsequent manual part of procedure, we found zonular dehiscence in the same area as indicated by LenSx AS-OCT, which extended to approximately 200° in the right eye and 180° in the left. After lens fragmentation by LenSx, we successfully removed the lens without further zonular dialysis. However, zonular dialysis (>180°) in the right eye was too large to insert an IOL, either in the capsule or the sulcus. Therefore, we performed scleral IOL implantation. In the left eye, we avoided using capsular tension ring (CTR) for IOL placement to avoid further iatrogenic damage to the zonule. Instead, an IOL was inserted into the sulcus with optic capture to reduce the possibility of further stress to the zonula and phimosis. Post-surgically, the patient regained good eyesight in both eyes. This case illustrates the advantages of FLACS in addressing zonulopathy. The consistent creation of CCC and lens fragmentation by FLACS may increase success rates, even in unexpectedly challenging cases.

Femtosecond laser-assisted successful management of subluxated cataractous lens with vitreous in anterior chamber

Femtosecond laser-assisted cataract surgery was performed in a case of posttraumatic cataract with six clock hours subluxation and vitreous in the anterior chamber (AC). Femtosecond laser pretreatment allowed a closed-chamber creation of corneal incisions, capsulotomy, and lens fragmentation with minimal sudden lens-diaphragm movements and zonular stress. Integrated imaging systems allowed customization of the size and position of capsulotomy and nuclear fragmentation, based on the extent and site of subluxation. Presence of vitreous in AC did not hamper femtosecond laser application. Triamcinolone-assisted vitrectomy was performed before phacoemulsification and after implanting the intraocular lens (IOL). Postoperative uncorrected visual acuity was 20/20 with a stable IOL.

[Morphological and clinical aspects of anterior capsulotomy in femtosecond laser-assisted cataract surgery]

The review covers morphological and clinical aspects of femtosecond laser-assisted anterior capsulotomy in cataract surgery. Literature data suggests that femtosecond laser-assisted capsulotomy is more accurate in size, shape, and centration than manual. Femtosecond laser-assisted anterior capsulotomy improves the accuracy of IOL positioning within the capsular bag.

Simultaneous pupil expansion and displacement for femtosecond laser-assisted cataract surgery in patients with lens ectopia

We describe a new approach for cataract surgery in ectopia lentis associated with an inadequately dilated pupil. A Malyugin ring 2.0 is first positioned in the eye to expand the pupil. One of the ring coils is then temporarily sutured to the limbal area with 10-0 polypropylene. With this maneuver, the pupillary expansion ring is placed in alignment with the center of the ectopic lens. Femtosecond laser anterior capsulotomy and lens fragmentation is then performed. Next, the temporary suture is released, a capsular hook(s) is placed to support the lens, and the lens is emulsified. A modified capsular tension ring is then inserted and sutured to the ciliary sulcus to center the capsular bag and the intraocular lens is implanted. This new technique for patients with insufficiently dilated pupils associated with ectopia lentis has the potential to improve surgical results and minimize complications in selected cases.

Femtosecond laser-assisted cataract surgery in a public teaching hospital setting

Background

To evaluate the efficiency and practicality of femtosecond laser assisted cataract surgery (FLACS) in a public teaching hospital setting using a mobile FLACS system compared to conventional phacoemulsification cataract surgery (CPCS).

Methods

Ninety eyes from 90 patients underwent either FLACS or CPCS (45 in each group). Cataracts were graded using the Lens Opacities Classification System III system. Outcome measures included total surgery duration, femtosecond laser treatment time, vacuum time (VT), total phacoemulsification time (TPT) and total phacoemulsification power (TPP).

Results

No differences were observed in the preoperative mean cataract grades and co-morbidities. FLACS took longer than CPCS with a mean difference of 5.2 ± 4.5 min (range: 0–18.8 min). The average femtosecond laser treatment time was 4.3 ± 3.4 min (range: 1–15.5 min). The VT was 2.51 ± 0.45 min (range: 1.59–4.10 min). Although not significant, TPT in FLACS showed a trend towards improvement (mean 1.0 ± 0.6 s; range: 0.1–2.4 s) compared to CPCS (mean 1.2 ± 0.6 min; range: 0.5–2.5 min). Whereas, TPP was significantly less in FLACS (mean 17.9 ± 5.0%; range: 5–27%) compared to CPCS (mean 20.3 ± 4.1%; range: 12.0–28.7%)(p = 0.031).

Conclusions

The mobile FLACS system housed in the same operating room increased the surgical duration by 5.2 min. The average VT was 2.51 min, which was lower in comparison to published experience using non-mobile FLACS systems.

Modified technique of endocapsular lens aspiration for severely subluxated lenses

PurposeSeverely subluxated crystalline lenses pose a difficult situation to anterior segment surgeons and can only be managed surgically by removal of the lens as well as the capsular bag. Several techniques have been described in literature for the management of such cases. We describe a modified technique of endocapsular lens aspiration by the limbal route for lens extraction through small incisions on the cornea.Patients and methodsThirty-two eyes of 16 consecutive patients with severely subluxated crystalline lenses were recruited in the study. All eyes underwent a modified technique of lens aspiration within the capsular bag using a single instrument, vitrectomy cutter, and irrigation cannula, followed by sacrificing of the capsular bag. The patients were either left aphakic or implanted with an open loop anterior chamber intraocular lens (ACIOL Kelman Multiflex) and prospectively followed up for a period of 3 months.ResultsThe mean age of the patients was 9 years 3 months±3 years (range 5-15 yrs). All eyes underwent complete lens aspiration within the capsular bag with no dislocation of the lens matter. ACIOL was inserted in 22 eyes (68.7%) and 10 eyes (31.2%) were left aphakic. All the surgeries were uneventful. The mean best corrected visual acuity (BCVA) at 3 months post surgery was 0.47±0.11 logMAR which was significantly better than pre-operative BCVA (P=0.001). The percentage endothelial cell loss at 3 months was 7.1%. There was no evidence of glaucoma, corneal decompensation, or retinal detachment. The astigmatism which increased from 1.45D±086 preoperatively to 3.76D±2.02 1 week post-operatively due to sutures reduced to 1.97D±0.81 post suture removal at 3 months.ConclusionThe modified technique of endocapsular lens aspiration proves to be a simple and effective method of removal of the lens-capsular bag complex in severely subluxated lenses.

Current and effective advantages of femto phacoemulsification

PURPOSE OF REVIEW

The purpose is to review the current and effective advantages of femtosecond laser-assisted cataract surgery (FLACS).

RECENT FINDINGS

FLACS has advantages over manual phacoemulsification in its precision, and predictability and may be especially advantageous in difficult situations such as shallow anterior chamber, subluxated cataracts, white cataracts, and so on. However, the femtosecond capsulorhexis may not be as strong as a manual rhexis. Laser-induced miosis is also a potential disadvantage.

SUMMARY

There may be increased surgeon confidence and patient satisfaction with FLACS and it may be friendlier to the internal structures of the eye. However, it is not superior to manual phacoemulsification in terms of primary outcomes such as visual and refractive outcomes or overall complications. Further refinements in technology may be needed to give it distinct advantages over manual phacoemulsification and to make it the norm in cataract surgery.

Management of Severely Subluxated Cataracts Using Femtosecond Laser-Assisted Cataract Surgery

PURPOSE

To assess the role of femtosecond laser technology in the management of severely subluxated cataracts.

DESIGN

Retrospective, interventional case series.

METHODS

All eyes with subluxated cataract seen between July 2012 and June 2015 were assessed for suitability for femtosecond laser-assisted cataract surgery, with the use of capsular tension devices. Participants with subluxated cataracts of at least 6 clock hours of zonular weakness were included in the study. Data collected included patient demographics, preoperative and postoperative best-corrected visual acuity (BCVA), nuclear density, extent of zonular weakness, completeness of capsulotomy, and complications. Poor visual outcome was defined as BCVA of worse than 20/40. Main outcome measure was the retention of the capsular bag.

RESULTS

Of the 72 eyes with subluxated cataracts undergoing surgery during the study period, 47 eyes of 47 patients were eligible for analysis. Mean age of the patients was 60.7 years (standard deviation [SD] 13.2 years). The majority were male (32, 68.1%) and Chinese (38, 80.8%). The mean duration of follow-up was 8 months (SD 5.6 months). The main identifiable cause of lens subluxation was trauma (11 eyes). Almost two thirds (30 eyes) had more than 9 clock hours of zonular weakness. Seventy percent of cataracts (33) were nuclear sclerosis grade 3 and above. The capsular bag was preserved in 43 eyes (91.5%). The intraocular lens was stable and centered at the last follow-up in all these 43 eyes. An anterior capsule tear occurred in 6 eyes, all of which had cataracts of nuclear sclerosis grade 3 and above, with posterior extension occurring in 3 eyes. Primary posterior capsule rupture occurred in 1 eye. At 1 month 37 eyes (80.4%) had a BCVA of 20/40 or better. There was significant improvement in BCVA at 1 month (mean of 0.92 logMAR units [SD 0.88] to 0.22 [SD 0.38] [P < .001, paired samples t test]), which was maintained at 1 year.

CONCLUSIONS

Selected cases of severely subluxated cataracts may be managed using femtosecond laser technology to perform the capsulotomy and nuclear fragmentation, with successful preservation of the capsular bag in 90% of eligible cases, especially in eyes with soft cataracts.

Safety of femtosecond laser-assisted cataract surgery: assessment of aqueous humour and lens capsule

PURPOSE

To investigate the effect of femtosecond laser-assisted cataract surgery (FLACS) on aqueous humour and lens capsule.

METHODS

This prospective randomized comparative study enrolled 19 eyes that underwent FLACS as the trial group and 20 eyes that underwent conventional phacoemulsification as the control group. The femtosecond laser platform (LLS-fs 3D; LensAR, Orlando, FL, USA) was used to generate capsulotomy (laser energy 8 μJ) and lens fragmentation (laser energy 10 μJ). Morphology of the cutting edge and cells of anterior capsule was assessed by light microscopy. The proteins in the aqueous humour were identified by mass spectrometry (Ultraflex III TOF/TOF; Bruker Dalton, Bremen, Germany). Electrolyte in the aqueous humour was detected by a chemistry analyzer (Aeroset Clinical Chemistry Analyzer; Abbott Laboratories, Abbott Park, IL, USA).

RESULTS

The cutting edge of anterior capsule was saw-tooth-shaped under magnification of 200× and 400× in the trial group, while it was smooth in the control group. Intact cells were found in the boundary area next to the cutting edge of anterior capsule in both groups. β-Crystallin B1, γ-crystallin S and transferrin were detected in the aqueous humour in the trial group. The concentrations of K⁺ , Na⁺ and Cl^- in the aqueous humour in the trial group differed significantly from those in the control group (p = 0.02, 0.03 and 0.04, respectively).

CONCLUSION

Femtosecond laser-assisted cataract surgery (FLACS) causes release of transferrin and crystallin from lens to aqueous humour and results in significant changes in the concentrations of K⁺ , Na⁺ and Cl^- in aqueous humour. However, these changes due to FLACS have no clinical significance or toxicity.

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.

Efficacy and Safety of Femtosecond Laser-Assisted Cataract Surgery Compared with Manual Cataract Surgery: A Meta-Analysis of 14 567 Eyes

TOPIC

To investigate the efficacy and safety of femtosecond laser-assisted cataract surgery (FLACS) relative to manual cataract surgery (MCS).

CLINICAL RELEVANCE

It is unclear whether FLACS is more efficacious and safe relative to MCS.

METHODS

A literature search of MEDLINE, EMBASE, and Scopus from 2007 to March 2016 was conducted. Studies containing both FLACS and MCS arms that reported on relevant efficacy and/or safety parameters were included. Weighted mean differences (WMDs) and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated.

RESULTS

From 2802 screened articles, 14 567 eyes from 15 randomized controlled trials and 22 observational cohort studies were included. For primary visual and refractive outcomes, no statistically significant difference was detected between FLACS and MCS in uncorrected distance visual acuity (WMD, -0.02; 95% CI, -0.04 to 0.01; P = 0.19), corrected distance visual acuity (WMD, -0.01; 95% CI, -0.02 to 0.01; P = 0.26), and mean absolute error (WMD, -0.02; 95% CI, -0.07 to 0.04; P = 0.57). In terms of secondary surgical end points, there was a statistically significant difference in favor of FLACS over MCS for effective phacoemulsification time (WMD, -3.03; 95% CI, -3.80 to -2.25; P < 0.001), capsulotomy circularity (WMD, 0.16; 95% CI, 0.11-0.21; P < 0.001), postoperative central corneal thickness (WMD, -6.37; 95% CI, -11.88 to -0.86; P = 0.02), and corneal endothelial cell reduction (WMD, -55.43; 95% CI, -95.18 to -15.69; P = 0.006). There was no statistically significant difference between FLACS and MCS for total surgery time (WMD, 1.25; 95% CI, -0.08 to 2.59; P = 0.07), capsulotomy circularity using a second formula (WMD, 0.05; 95% CI, -0.01 to 0.12; P = 0.10), and corneal endothelial cell count (WMD, 73.39; 95% CI, -6.28 to 153.07; P = 0.07). As well, there was a significantly higher concentration of prostaglandins after FLACS relative to MCS (WMD, 198.34; 95% CI, 129.99-266.69; P < 0.001). Analysis of safety parameters revealed that there were no statistically significant differences in the incidence of overall complications between FLACS and MCS (RR, 2.15; 95% CI, 0.74 to 6.23; P = 0.16); however, posterior capsular tears were significantly more common in FLACS versus MCS (RR, 3.73; 95% CI, 1.50-9.25; P = 0.005).

CONCLUSIONS

There were no statistically significant differences detected between FLACS and MCS in terms of patient-important visual and refractive outcomes and overall complications. Although FLACS did show a statistically significant difference for several secondary surgical outcomes, it was associated with higher prostaglandin concentrations and higher rates of posterior capsular tears.

Phacoaspiration with a Cionni ring versus pars plana lensectomy, vitrectomy and sutureless transscleral IOL fixation in pediatric patients with a subluxated lens

PURPOSE

To compare outcomes of phacoaspiration (PA) with Cionni ring-assisted posterior-chamber intraocular lens implantation (PCIOL) versus pars plana lensectomy (PPL) with anterior vitrectomy (AV) and sutureless transscleral fixation of the IOL (TSFIOL) assisted with fibrin glue in the management of a subluxated lens.

METHODS

In this prospective and comparative interventional study, one eye of children with a bilateral subluxated lens was randomized to undergo PA with PCIOL using a Cionni ring (group A: n = 14 eyes), and the other eye underwent PPL + AV with glue-assisted TSFIOL (group B: n = 14 eyes). The outcome measures included best-corrected visual acuity (BCVA) in logMAR units and rates of complications at 12-month follow-up visits.

RESULTS

28 eyes of 14 children (age: 8.06 ± 4.49 years) were included in the study. BCVA improved from preoperative value of 1.21 to 0.4 (p = 0.001) in group A and from 1.53 to 0.31 (p = 0.001) in group B at month 12. There was no significant difference in the BCVA on comparing the two groups at month 12 (p > 0.411). Postoperative complications in group A included corneal edema (two eyes), Cionni hook capture (one eye), elevated IOP (one eye), and posterior capsular opacification (five eyes). In group B, corneal edema was seen in two eyes, hypotony in one eye, vitreous hemorrhage in one eye and pupillary optic capture in four eyes.

CONCLUSION

Head-to-head comparison of the two techniques demonstrates no significant difference in the rates of complications at month 12. The decision to choose either technique may be based on the operating surgeon's skill, experience and preference.