Review of manual small-incision cataract surgery

Evaluation of Parameters and Nozzle Tip Damage after Clinical Use of Three Hydrophilic Intraocular Lens Injector Models

Purpose

To assess the nozzle tip damage and the parameters of three different hydrophilic intraocular lens (IOL) injector models.

Methods

After routine cataract surgeries at the University Eye Hospital Heidelberg, all the used IOL injectors were collected from the operating room and sent to our laboratory. Nozzle tip damage was assessed under a microscope and graded as follows: no damage (grade 0), slight scratches (1), deep scratches (2), extensions (3), cracks (4), and bursts (5). Each damage grade was assigned a score from 0 to 5, and the total damage score for each injector system was calculated and compared. Nozzle tip parameters (diameters and areas), plunger tip parameters, and tip angles were also measured in each model.

Results

The damage scores were (median, Q3-Q1): 1 (1-1) for Accuject, 1 (1-1) for Bluemixs, and 1 (1-1) for RayOne. There was no statistically significant difference in the damage scores between the study groups (P > 0.05). The outer cross-sectional vertical and horizontal diameters were 1.69 and 1.69 mm for Accuject, 1.69 and 1.69 mm for Bluemixs, and 1.70 and 1.71 mm for RayOne. Plunger tip areas were 0.78 mm2 for Accjuect, 0.74 mm2 for Bluemixs, and 0.43 mm2 for RayOne. Plunger tip area/inner cross-sectional area of the nozzle tip (%) was 31.2% for RayOne, 66.7% for Accuject, and 63.8% for Bluemixs. The tip angles for three injector models were 56° (Accuject), 56° (Bluemixs), and 44° (RayOne).

Conclusions

All the injector models showed mild to moderate damage to the nozzle tip after IOL implantation, even with smaller diameter tips. RayOne resulted in the lowest ratio between plunger tip area and inner cross-sectional area of the nozzle tip and a better distribution of damage categories than the other two groups. All three injector models had relatively small tip parameters. If smaller incisions are required in certain patients, smaller tip parameters should be considered.

Outcomes of "Complex" Cataract Surgeries Performed by Long-Term Glaucoma Fellows in a Tertiary Eye Centre from Eastern India

Purpose

To evaluate the outcomes of operating on "complex cataracts" by the glaucoma fellows.

Patients and Methods

This was a retrospective study done at a tertiary referral eye care centre in eastern India. After obtaining IRB approval, a retrospective chart review of all patients who underwent "complex" cataract surgery by one of four long-term (2 years) glaucoma fellows between January 2016 and November 2020 was conducted. 'Complex' was defined as cataracts complicated with pseudoexfoliation syndrome, phacodonesis with or without blunt ocular trauma, posterior polar cataract, small pupil, co-existent corneal opacity or uveal coloboma, post-glaucoma filtering surgery, post-vitreoretinal surgery, co-existent glaucoma or post-laser iridotomy and monocular patients.

Results

Out of a total of 677 eyes done by the glaucoma fellows during the study period, 83 eyes had complex cataract surgery and completed the six-week post-operative follow-up. Intraoperative surgical complications like posterior capsular rent or vitreous loss were noted in 36 of the cases. Thirty of the eyes were left aphakic. Despite a high rate of complications, the LogMAR best-corrected visual acuity (mean ± standard deviation) improved from the preoperative level of 1.7 (±0.5) to 1.0 (± 0.8) at post-operative six weeks, significant at p < 0.001. As far as the surgeon's experience was concerned-less than or more than a year since joining the fellowship-there was statistically no difference in the final visual acuity. The group with greater experience had shorter surgical time and lesser complications though this difference was not statistically significant.

Conclusion

This is the first study in the literature reporting the outcomes of "complex" cataract surgery performed by glaucoma fellows. Though high rates of postoperative complications were noted in this study, the mean best-corrected visual acuity improved significantly in all eyes after the surgery.

Twelve month outcome of manual small-incision cataract surgery in Assiut, Egypt: A retrospective study with a large sample size

BACKGROUND

To assess the visual outcome of manual small-incision cataract surgery (MSICS) as well as safety, cost, and time of the procedure.

PATIENTS AND METHODS

A retrospective study involving candidates for cataract surgery with baseline-corrected distance visual acuity (CDVA) ≤20/120. Visual acuity (VA) was the primary outcome measure while surgical complications, cost, and time of surgery were the secondary outcome measures. Follow-up visits were scheduled at 1 day, 1 week, 1 month, and at 6 and 12 months following surgery.

RESULTS

The study enrolled 3007 patients with a mean age of 66.45 ± 17.3 years. Out of 3007 patients, 2774 (92.2%) were legally blind before surgery (CDVA <20/200) which was significantly reduced to 55 patients (1.9%) by 1 month following surgery. Uncorrected distance visual acuity was 20/60 or better in 2098 eyes (69.8%) at 1 month, in 2035 eyes (67.7%) at 6 months, and in 2017 eyes (67.1%) at 12 months. The posterior capsular rupture was the most common intraoperative complication. Corneal edema was the most common immediate postoperative complication while the development of posterior capsular opacification was the leading cause for later impaired VA. The mean cost was approximately equivalent to 20 US dollars. The median duration of surgery was 10 min.

CONCLUSION

MSICS is a safe, cost-effective, and time-saving technique for improving the vision of cataract patients in areas with high cataract surgery volume and limited facilities.

Re-inventing the straight incision with a single central suture in manual small-incision cataract surgery to minimize surgically induced astigmatism

Purpose

To calculate the surgically induced astigmatism (SIA) in MSICS through a superiorly placed straight scleral incision closed with a single, central, perpendicular 10-0 polyamide suture and to document any suture-related complaints and complications.

Methods

A retrospective, hospital-based study was carried out in 50 cases of uncomplicated senile cataract (&gt;50 year) with nuclear sclerosis ≥ grade 4, "with the rule" astigmatism who underwent MSICS through a superior, straight incision with a single, central, perpendicular 10-0 nylon suture. Patients with "against the rule" astigmatism, keratoconus, pre-existing corneal opacity, astigmatism &gt;2D, distorted or oblique mires, and previous ocular surgeries and unwilling to participate were excluded.

Results

The mean age of the patients was 64.81 + 2.824 years, with a male: female ratio of 1.38:1. The mean SIA at day 7, week 6, and 12 weeks was 0.539 + 0.118, 0.529 + 0.134, and 0.524 + 0.129, respectively. Only 6 patients (12%) complained of foreign body sensation. No patient developed any suture-related complications.

Conclusion

SIA is significantly reduced in straight incision by applying a single, central, and perpendicular 10-0 polyamide suture, as compared to a straight incision without a suture.

Endoexpression technique of nucleus delivery in manual small-incision cataract surgery

Manual small-incision cataract surgery (MSICS) is a cost-effective alternative to phacoemulsification and extracapsular cataract extraction (ECCE) for cataract surgery. The surgical technique in MSICS is heterogeneous, and the maximum variation exists in incision and nucleus delivery techniques. Many studies on various incisions are available, and most of them are dedicated to surgically induced astigmatism (SIA), utility, and visual outcomes. The nucleus delivery techniques have less-extensive literature available. They can be divided into "pulling" techniques like phacosandwich technique, fish hook technique, and vectis delivery and "pushing" techniques like viscoexpression or hydroexpression with irrigating vectis/Blumenthal's MiniNuc technique. Postoperative surgical-induced astigmatism is comparable in all techniques. The authors describe a pushing technique which does not raise the pressure of the anterior chamber and can be utilized with variable-sized and irregularly shaped nuclear fragments. It has universal application, especially when the size of the incision is getting smaller in MSICS and phacofragmentation is being used as an adjunct to reduce the incision size. It can be used in situations like posterior polar cataracts, where pressure variations in the anterior chamber can be dangerous.

Snare assisted manual small-incision cataract surgery: Single solution for any grade of cataract

Cataract surgery is constantly evolving with new techniques, machines, and procedures entering the lexicon. With the modernization, the cost of surgery is increasing with respect to the surgeon, patient, and the society. Early rehabilitation with modern minimal access techniques reduces the societal cost of intervention. Manual small-incision surgery is simple, safer, and cheaper when contrasted with the cost and steep learning curve of machine-driven surgeries. A nucleus of a normal size is 6 mm, which can be bisected; 3 mm longitudinal fragments can be removed through 3.5 to 4.5 mm incision, and a large nucleus of 9.0 mm can trisected and removed through 3.5 to 4.5 mm. The limbal tunnel incision is 3.5 mm, which is close to 2.8 mm phacoincision, so it gives all the advantages of modern phacosurgery. The search of an ideal technique for manual phaco-fragmentation leads us to this specially designed snare (designed by the first author AS) which can tackle any grade nucleus. The nucleus can be bisected or trisected with ease. The technique has been around for 2 decades. There is a small learning curve. The complications are few and can be minimized with practice and simulation. It is a safe, valid, repeatable, and generalizable surgical procedure.

Evaluation of cautery in manual small-incision cataract surgery

Purpose

Manual small-incision cataract surgery (MSICS) has a major role in tackling cataract blindness in our country. Cauterization of sclera is one of the important steps performed in MSICS to have bloodless field during surgery. Only few studies have addressed the effect of cautery on post-operative astigmatism. The present study is designed to evaluate the effect of cautery on surgically induced astigmatism in Indian patients.

Methods

The study was designed as a prospective randomized trial conducted in a tertiary health care institution over a period of 2 years. A total of 150 eyes were randomized into two groups. The study group (Group 1, n = 75) underwent MSICS with cauterization using wetfield bipolar cautery with 4 amperes power. In the control group (Group 2, n = 75), no cauterization was performed. Surgically induced astigmatism was calculated using Naesers polar value method and compared between these two groups up to 60 days post-operatively.

Results

Data from 150 eyes were available for evaluation. The net post-operative astigmatic value was 1.01 ± 0.21, 1.04 ± 0.19, and 1.03 ± 0.22 D on the 1^st, 7^th, and 30^th post-operative days, respectively, showing a stable trend in patients undergoing cauterization. In Group 2, the net post-operative astigmatic values observed were 0.47 ± 0.11 D, 0.54 ± 0.10, and 0.54 ± 0.09 D on the 1^st, 7^th, and 30^th post-operative days, respectively. The mean value of surgically induced astigmatism at 2 months post-operatively with and without cautery was 0.60 ± 0.20 D at 90° and 0.47 ± 0.10 D at 90°. The difference was not statistically significant (P = 0.08).

Conclusion

The results of this study show that the use of cautery in MSICS is not associated with a higher surgically induced post-operative astigmatism. The magnitude of surgically induced astigmatism decreases with time.

Comparison of the outcomes of phacoemulsification and manual small-incision cataract surgery in posterior polar cataract - A retrospective study

Purpose

To compare the visual outcomes and intraoperative complications between phacoemulsification and manual small-incision cataract surgery (MSICS) in cases of posterior polar cataract (PPC).

Methods

A retrospective study was carried out involving 142 patients (164 eyes) with PPC who underwent cataract surgery between January and December 2017. Data collected include the demographic details, preoperative uncorrected visual acuity (UCVA), best corrected visual acuity (BCVA), type of cataract, intraocular pressure, anterior and posterior segment findings, type of surgery performed, intraoperative complications, postoperative UCVA on the first day, UCVA and BCVA at 1 month after surgery, complications, and resurgery details.

Results

In total, 90 patients (107 eyes) underwent phacoemulsification, and 52 patients (57 eyes) underwent MSICS. There was no significant difference in the mean age, sex, and type of PPC between the two groups (P = 0.326, 0.852, and 0.220, respectively). Patients who underwent phacoemulsification had significantly better preoperative BCVA (P = 0.002). The BCVA on first postoperative day and 1 month after surgery was better in the phacoemulsification group than in the MSICS group (P &lt; 0.001 and 0.002, respectively). The overall incidence of posterior capsular rupture (PCR) was 11.6%, which included the 10.3% in phacoemulsification and 14.0% in MSICS. There was, however, no significant difference in the rates of PCR between the two groups (P = 0.506).

Conclusion

Phacoemulsification delivered better postoperative visual outcomes than MSICS in PPC patients, whereas the complication rates were similar between the two groups.

Factors affecting surgically induced astigmatism in manual small-incision cataract surgery

Cataract is the most common cause of avoidable blindness in the world. While cataract surgery is continually evolving, manual small-incision cataract surgery (MSICS) still remains highly relevant, especially with the threat of the coronavirus disease 2019 (COVID-19) still looming large over the world. MSICS today has a renewed significance, since it does not involve the use of any advanced machinery and relies mainly on easily sterilizable instruments, thereby making it a safe and inexpensive option. A self-sealing valvular tunnel entry forms the basis of MSICS, and proper positioning and construction of the tunnel is imperative to the success of the surgery. With more and more people demanding spectacle independence after surgery, it becomes important to have a thorough understanding of the factors that may influence surgically induced astigmatism in MSICS. These include the incision location, size and shape, configuration of the sclero-corneal tunnel, pre-existing ocular pathology, role of sutures, amongst others. With proper knowledge, many of these factors can be modulated to achieve best results.

Comparison of corneal endothelial cell loss during manual small-incision cataract surgery using viscoelastic-assisted nucleus removal versus continuous balanced salt solution plus technique - Randomized controlled trial

Purpose

The purpose of this study was to compare and analyze the endothelial cell loss during manual small-incision cataract surgery (MSICS) using the viscoelastic-assisted nucleus removal versus basal salt solution plus technique.

Methods

This was a prospective randomized trial of 204 patients who underwent MSICS using viscoelastic-assisted nucleus removal (Group 1- OVD) versus basal salt solution plus technique (Group 2- BSS) at a tertiary eye care hospital in North India from January 2018 to 2021. Of these 204 patients, 103 (50.5%) and 101 (49.5%) were allocated to Group 1 and 2, respectively. The parameters assessed were detailed history, demographics, and anterior and posterior segment details. Visual acuity, intraocular pressure (IOP), keratometry, pachymetry, and endothelial cell density were evaluated preoperatively and postoperatively on day 1 and 30.

Results

The mean age of the patients was 64.5 ± 8.2 years (range 48-82 years). There were 129 (63.2%) males and 75 (36.8%) females. The mean LogMAR visual acuity for both groups on day 1 (Group 1- 0.3 ± 0.1, Group 2- 0.5 ± 0.2) and day 30 (Group 1- 0.1 ± 0.2, Group 2- 0.1 ± 0.1) was statistically significant (P &lt; 0.001), and the mean IOP value showed a statistically significant value (P &lt; 0.009) on day 1 in Group 2 (15.0 ± 2.4 mmHg) and on day 30 (P &lt; 0.001) in both the groups (Group 1- 13.6 ± 1.8 mmHg, Group 2- 13.5 ± 2 mmHg). The horizontal and vertical k values also showed a statistically significant difference on day 1 and day 30 (P &lt; 0.001). The mean percentage change of central corneal thickness (CCT) in Group 1 was 17.7% and in Group 2 was 17.4% on day 1, and it was 1.1% on day 30 in both the groups, which was statistically significant (P &lt; 0.001) compared to preoperative values. The percentage change in endothelial cell density on day 1 was 9% in Group 1 and 4.6% in Group 2, which was statistically significant (P &lt; 0.001). On day 30, it was 9.7% and 4.8%, respectively, which was statistically significant (P &lt; 0.001).

Conclusion

Our study highlights statistically significant endothelial cell loss with viscoelastic-assisted nuclear delivery compared to BSS-assisted nuclear delivery during MSICS in a short follow-up of 1 month. The CCT values showed a slight increase, and the keratometry and IOP were unaffected compared to the preoperative parameters in both the groups.

Evolution of manual small-incision cataract surgery from 8 mm to 2 mm - A comprehensive review

Cataract is the most common cause of reversible blindness worldwide, accounting for approximately 50% of blindness worldwide. Cataract surgery is the most common surgical procedure performed in routine ophthalmic practice. It has undergone tremendous evolution, and the incision size has progressively reduced from 10-12 mm in extracapsular cataract surgery (ECCE) to 6-8 mm for manual small-incision cataract surgery (MSICS) and 2.2-2.8 mm in phacoemulsification. In a developing country like India, with a massive backlog of cataract, everyone cannot afford private surgery like phacoemulsification. Moreover, annual maintenance of the machine, cost of foldable IOLs, need for greater skill, learning curve, and difficulty in performing the surgery in mature and brown cataracts are other barriers. Due to these factors, MSICS is the surgery of choice in the developing world, with profound societal and economic benefits and similar visual recovery compared to phacoemulsification. During the last two decades, MSICS gained popularity in developing countries and has undergone tremendous advances. This article aims to review the various techniques of MSICS and how the surgery has evolved over the years, particularly focusing on the current technique of 2-mm MSICS.

Overcoming the impact of physiologic tremors in ophthalmology

PURPOSE

Ophthalmic surgery involves the manipulation of micron-level sized structures such as the internal limiting membrane where tactile sensation is practically absent. All humans have physiologic tremors that are of low amplitude and not discernible to the naked eye; they do not adversely affect the majority of the population's daily functioning. However, during microsurgery, such tremors can be problematic. In this review, we focus on the impact of physiological tremors on ophthalmic microsurgery and offer a comparative discussion on the impact of such tremors on other surgical specialties.

METHODS

A single investigator used the MEDLINE database (via PubMed) to search for and identify articles for inclusion in this systematic review. Ten key factors were identified as potentially having an impact on tremor amplitude: beta-blockers, muscle fatigue, robotic systems, handheld tools/micromanipulators, armrests/wrist supports, caffeine, diet, sleep deprivation, consuming alcohol, and workouts (exercise). These key terms were then searched using the advanced Boolean search tool and operators (i.e., AND, OR) available on PubMed: (*keyword*) AND (surgeon tremor OR microsurgery tremor OR hand steadiness OR simulator score).

RESULTS

Ten studies attempted to quantify the baseline severity of operator physiologic tremor. Approximately 89% of studies accessing the impact of tremors on performance in regards to surgical metrics reported an improvement in performance compared to 57% of studies concluding that tremor elimination was of benefit when considering procedural outcomes.

CONCLUSIONS

Robotic technology, new instruments, exoskeletons, technique modifications, and lifestyle factors have all demonstrated the potential to assist in overcoming tremors in ophthalmology.

Visual Outcome Following Manual Small Incision Cataract Surgery at a Tertiary Center in South India

Introduction

Cataract being one of the leading causes of avertible blindness has been found to be quite prevalent in developing countries like India. The National Programme for Control of Blindness (NPCB) aims at reducing blindness due to cataract via cataract control programs. The most commonly performed surgery is the manual small incision cataract surgery (MSICS).

Aim

The aim of this study was to determine the visual acuity and outcome in patients who underwent MSICS in a tertiary hospital in south India.

Methodology

A prospective longitudinal interventional study was conducted in a tertiary hospital in Karnataka, India, over a period of nine months. A total of 105 eyes underwent MSICS and were followed up for one month to assess their postoperative visual outcome and complications, if any. During this period, they were started on antibiotic + steroid combination eyedrops, which were tapered over four weeks.

Results

Results were assessed based on visual grading categorized by the World Health Organization (WHO). A total of 103 (98.1%) patients had good vision, i.e., visual acuity of 6/6 - 6/18, followed by two (1.9%) who had moderate vision i.e., visual acuity of <6/18 - 3/60, and none were blind or with visual acuity of <3/60. Complications seen intraoperatively in two patients (1.9%) were iris prolapse and posterior capsular rent, respectively, and postoperatively one (0.95%) patient showed hyphema with inferior haptic in the anterior chamber.

Conclusion

This study proves that a good visual outcome with a low complication rate can be achieved after MSICS with posterior chamber intraocular lens implantation.

Cataract Surgery Numbers in U.S. Ophthalmology Residency Programs: An ACGME Case Log Analysis

PURPOSE

To describe and assess the cataract experience of ophthalmology residents throughout the United States (U.S.).

METHODS

Cataract procedures logged by graduating ophthalmology residents nationwide and published by the Accreditation Council for Graduate Medical Education (ACGME) from 2009 to 2020 were analyzed using linear regression on log-transformed response variables with robust variance.

RESULTS

As primary surgeon, average numbers logged for phacoemulsification increased yearly by an average of 4.1% prior to 2019 and then decreased by 22.1% in 2019 for an overall average yearly increase of 2.9% (95% CI: 0.5, 5.4%, p = .03), non-phacoemulsification extracapsular extraction decreased yearly by an average of 4.6% (95% CI: -7.7, -1.5%, p = .01), other cataract/intraocular lens surgeries decreased yearly by an average of 8.4% (95% CI: -10.1, -6.6%, p < .001), anterior vitrectomies decreased yearly by an average of 12.5% (95% CI: -14.9, -10.1%, p < .001), and laser capsulotomies increased yearly by an average of 6.0% prior to 2019 and then decreased by 3.0% for an overall average yearly increase of 5.3% (95% CI: 4.5, 6.2%, p < .001). As assistant, average numbers logged in all ACGME minimum categories showed decreasing trends.

CONCLUSIONS

Over the last decade, the average numbers of phacoemulsification and laser capsulotomies logged by residents as primary surgeon increased while other ACGME cataract minimum procedures decreased. Surgical volume in 2019-20 was lower due to the coronavirus disease-19 pandemic but higher than from 2009 to 2013.

Phacoemulsification: Proposals for Improvement in Its Application

A cataract is defined as opacity of the crystalline lens. It is currently one of the most prevalent ocular pathologies and is generally associated with aging. The most common treatment for cataracts is surgery. Cataract surgery is a quick and painless process, is very effective, and has few risks. The operation consists of removing the opacified lens and replacing it with an intraocular lens. The most common intraocular lens removal procedure that is currently used is phacoemulsification. The energy applied in this process is generated by ultrasonic waves, which are mechanical waves with a frequency higher than 20 kHz. A great deal of research on the different ways to perform the stages of this surgical procedure and the analysis of the possible side effects of the operation has been published, but there is little information on the technical characteristics, the intensities applied, and the use of ultrasound-emitting (U/S) equipment for cataract removal. More studies on the method and depth of absorption of ultrasonic waves in our visual system when performing the phacoemulsification procedure are needed. It would be advisable for health authorities and medical professionals to develop guidelines for the handling and use of ultrasonic wave-emitting equipment, such as those that exist for ultrasound and physiotherapy. This could help us to reduce undesirable effects after the operation.

Anterior Subconjunctival Anesthesia for Manual Small Incision Cataract Surgery: A Randomized Controlled Trial

Purpose:

To compare the effectiveness of anterior subconjunctival anesthesia (ASCA) with sub-tenon's anesthesia (STA) for manual small incision cataract surgery (MSICS), regarding pain, akinesia, surgeon comfort, and complications.

Methods:

This trial randomized 164 patients into two groups. Group 1 received ASCA, and Group 2 received STA. MSICS was performed on all patients. Any complications of anesthesia were noted before starting surgery. Patient ocular motility during surgery was scored between 0 and 4 based on the number of directions of gaze in which movement persisted. Following surgery, patients scored pain felt during surgery on a visual pain-score analog, and the surgeon graded for “discomfort” felt during surgery from 0 (Nil) to 4 (additional anesthesia needed).

Results:

Chemosis due to anesthesia and persistence of ocular motility in all four gaze directions were seen in all 82 patients of Group 1, but these did not prevent the surgeon from performing MSICS. Seventy-seven patients (94%) in Group 1 and 79 (96.4%) in Group 2 had no or mild pain during surgery. The surgeon had moderate-to-severe discomfort in 14 (17.2%) Group 1 patients and 3 (3.6%) Group 2 patients, most of whom had deep-set eyes or exhibited excessive eye movements. Two patients in Group 1 and one patient in Group 2 were converted to peribulbar block.

Conclusion:

ASCA is a safe and effective alternative for performing MSICS. It does not induce akinesia but provides adequate anesthesia for the surgery in most patients, except those with deep-set eyes, especially if displaying increased anxiety.

The impact of limbus detection, arcus lipoides and limbal vessels on the primary patency of clear cornea incisions in femtosecond laser-assisted cataract surgery

PURPOSE

To analyse the factors influencing the primary patency of clear corneal incisions in femtosecond laser-assisted cataract surgery (FLACS).

METHODS

In this prospective single-centre study, the graphical user interfaces of 159 patients undergoing femtosecond laser-assisted cataract surgery were documented by video. Subsequently, the quality of limbus detection along with the incidence of vessels and an arcus lipoides were assessed by a grading system and analysed in relation to the primary patency of the incisions. In particular, the differences between a superior and a temporal main incision were analysed.

RESULTS

The designed grading system could be applied in all cases without any problems. Limbus detection was highly inhomogeneous but had no influence on the patency of the incisions (46.3% poor, 18.4% moderate, 35.1% good). The characteristics of the arcus lipoides had little influence on the patency of the main incisions. Pronounced vascular ingrowth caused more tissue bridges but did not reduce the patency of the incisions. Temporal access was generally easier to open than a superior one (97.1% versus 88.9%).

CONCLUSION

We showed a patency rate of superior FLACS incisions of over 97% with the Femto LDV Z8 in our study. Temporal main incision is preferable to superior main incision in more difficult situations. The new grading system is suitable for further studies to provide information on the quality of the incision.

Resident Performed Sutureless Manual Small Incision Cataract Surgery (MSICS): Outcomes

Purpose

To show the surgical and visual outcomes of a resident-performed manual small incision cataract surgery.

Study Type

Retrospective observational case series.

Study Setting

Ruby Eye Hospital.

Materials and Methods

Manual small incision cataract surgery was performed on 339 uncomplicated cataract cases by three in-house residents. Preoperative visual acuity and vision with a pinhole were meticulously noted in the record sheets. All patients underwent thorough preoperative evaluation with the help of a slit lamp. Eyes with corneal guttae, un-dilated pupils, pseudo-exfoliation, raised intraocular pressure and posterior segment abnormalities were excluded from the study. The mean patient age was 59 years (min: 47 years and max: 85 years). Forty-seven percent were males, and the rest were females. The mean uncorrected preoperative visual acuity recorded was 1.3 logMAR units (max: 1 and min: 1.6, Std dev: 0.4). Forty-two percent of the eyes had dense nuclear cataracts (≥ Nuclear Sclerosis grade III from LOCS II).

Results

The mean postoperative visual acuity recorded was 0.4 logMAR units [standard deviation 0.3 logMAR units (max: 1 and min: 0.1 p-value <0.001)]. Forty-three cases (12.6%) had tunnel-related complications (premature entry/button hole). Thirty-six cases (10.6%) had iatrogenic prolapse of the iris tissue. Eight cases (2.3%) had a runaway capsulorhexis, while 18 cases (5.3%) had iatrogenic posterior capsular rupture. Two cases (0.58%) had a large zonular dialysis. Ten cases (2.9%) were retaken to the operating room again for repeat intervention.

Conclusion

The ophthalmic resident learning curve for manual small incision cataract surgery is steep, unlike what is reported in the literature. A good training program with a special emphasis on wound construction is of paramount importance for future residents.

Simulating Outcomes of Cataract Surgery: Important Advances in Ophthalmology

As the human eye ages, the crystalline lens stiffens (presbyopia) and opacifies (cataract), requiring its replacement with an artificial lens [intraocular lens (IOL)]. Cataract surgery is the most frequently performed surgical procedure in the world. The increase in IOL designs has not been paralleled in practice by a sophistication in IOL selection methods, which rely on limited anatomical measurements of the eye and the surgeon's interpretation of the patient's needs and expectations. We propose that the future of IOL selection will be guided by 3D quantitative imaging of the crystalline lens to map lens opacities, anticipate IOL position, and develop fully customized eye models for ray-tracing-based IOL selection. Conversely, visual simulators (in which IOL designs are programmed in active elements) allow patients to experience prospective vision before surgery and to make more informed decisions about which IOL to choose. Quantitative imaging and optical and visual simulations of postsurgery outcomes will allow optimal treatments to be selected for a patient undergoing modern cataract surgery.

The visual outcomes and complications of manual small incision cataract surgery and phacoemulsification: long term results

Objective: To compare visual outcomes and complications between manual small incision cataract surgery (MSICS) and phacoemulsification.

Methods: A retrospective study was conducted in the tertiary care center. A total of 1281 cases underwent manual small incision cataract surgery and phacoemulsification from January 2014 to December 2016. The postoperative best corrected visual acuity (BCVA) along with the rates of complications were compared between both groups.

Results: Five hundred and twenty-one patients (40.67%) and 760 patients (59.33%) were subjected by staff members and residents, respectively. Altogether, 689 cases (53.79%) were subjected to MSICS technique and 592 cases (46.21%) to phacoemulsification. The MSICS group had significantly harder cataract (cataract grading ≥ 4+ :31.64% vs. 7.77%; p<0.001). One month postoperatively, good visual outcome (BCVA ≥ 6 /18) in the phacoemulsification group was higher than that in the MSICS group (86.33% vs. 72.12%, p<0.001). The risk factor for poor outcome (post-operative BCVA < 6 /60 in both groups) was the presence of associated ocular pathologies. The intraoperative and perioperative complications rates were higher in the MSICS group (16.55% vs. 6.6%, p<0.001). The most common complications were hyphema (4.35%), posterior capsule ruptures (4.21%), and prolapsed iris (3.05%). Long-term postoperative complication rates were higher in the phacoemulsification group (9.29% vs. 21.28%, p<0.001). The most common complication was posterior capsule opacity (8.71% vs. 20.44%, p<0.001). Pseudophakic bullous keratopathy (PBK) was similar in both groups (0.29% vs. 0.17%, p=1.00).

Conclusion: The number of patients who had experienced good visual outcomes was higher in the phacoemulsification group. However, for both groups, no significant differences were found on the long-term complication rate.

Reasons for explantation of phakic intraocular lenses and associated perioperative complications: cross-sectional explant registry analysis

Background

We discuss the safety, since their introduction, of phakic intraocular lenses (pIOLs) to correct refractive errors in healthy eyes. We investigated the reasons for pIOL explantation and the associated perioperative complications.

Methods

This retrospective, cross-sectional study included 69 pIOLs, explanted at a single tertiary center between July 2005 and March 2020: 34 angle-supported (G1), 28 iris-fixated (G2) and seven posterior chamber (G3) pIOLs. Case data including the reason for explantation was taken from the patient records. Intra- and postoperative complications were evaluated for an association with the pIOL.

Results

The mean duration in the eye was 10.4 (0.2–28) years. Cataractogenesis and subsequent surgery that required pIOL explantation was the reason in 42% of all cases. In 22%, cataract in combination with endothelial damage prompted explantation, with 26, 18 and 14% for G1, G2 and G3 respectively. The second most common reasons were corneal damage alone in the angle-supported group (26%), IOL subluxation in the iris-fixated group (18%), and photopic disturbance in the posterior chamber group (29%). In 68% of all explantations, the surgical course was unremarkable, while in the remaining cases perioperative complications were associated with the lens in 45.7%.

Conclusion

Overall, the need for cataract surgery was the most common reason for pIOL explantation. Corneal complications were more frequent in the angle-supported pIOLs and their removal was associated with higher rates of complication compared to the other groups.

Misalignment and tilt effect on aspheric intraocular lens designs after a corneal refractive surgery

PURPOSE

To numerically evaluate and compare the tolerance to misalignment and tilt of aspheric intraocular lenses (IOLs) designed for three eyes: with standard cornea and with simulated corneas after myopic and hyperopic laser ablation surgery.

METHODS

Three aspheric IOLs of +20.00 diopter (D) with different spherical aberration (SA) ([Formula: see text]) values have been designed using a theoretical model eye. Drastic changes on the theoretical eye anterior corneal asphericity have been performed to simulate myopic and hyperopic refractive surgeries. The effect of IOL misalignment and tilt on the image quality has been evaluated using a commercial optical software design for the three eye models. Image quality was assessed from the modulation transfer function (MTF), root mean square (RMS) values of defocus, astigmatism, coma and spherical aberration ([Formula: see text]), and retinal images obtained from a visual simulator using an aleatory optotype of 0.00 LogMar visual acuity (VA).

RESULTS

IOL misalignment and tilt reduced MTF values in general, and increased wavefront aberrations errors. Aberration-free IOLs maintained best the MTF values when misalignments were applied, together with good on-axis optical quality. IOLs with negative SA ([Formula: see text]) correction decreased the MTF value under 0.43 for misalignments values higher than 0.50 mm with the three corneas. The effect of misalignment on RMS astigmatism and coma was correlated with the IOL SA ([Formula: see text]) and with the three corneas.

CONCLUSIONS

This theoretical study shows that the largest degradation in image quality arises for the IOL with the highest amount of spherical aberration ([Formula: see text]). Moreover, it has been found that the aspherical design has a more influential role in misalignment tolerance than in tilt tolerance.

Modified manual small incision cataract surgery technique for phacoemulsification-trained surgeons

Purpose:

To present the technique and outcomes of a modified manual small incision cataract surgery designed for the phacoemulsification surgeons who are learning to perform manual small incision cataract surgery.

Methods:

This was a retrospective, single-centred, comparative study. We included all the patients who underwent the modified manual small incision cataract surgery for visually significant cataract at Singapore National Eye Centre. All surgeries were performed by either a senior phaco-trained surgeon (M.A.) who had performed more than 500 manual small incision cataract surgery or a junior phaco-trained surgeon (D.C.) who had performed around 500 phacoemulsification but never performed any manual small incision cataract surgery. The main modification of this technique lies in the creation of an additional phaco-like main wound at 90° to the scleral tunnel wound, with most surgical steps performed through this additional wound. The outcomes were analysed and compared between the senior and junior surgeons. The main outcome measures were visual outcome and major intraoperative complications such as posterior capsular rupture and zonular dialysis.

Results:

A total of 132 cases were included; 102 (77.3%) and 30 (22.7%) cases were performed by the senior and junior surgeons, respectively. Pre-operatively, 85.6% eyes had best-corrected visual acuity of counting fingers or worse. Postoperatively, the visual outcome at 1 month was similar between the senior and junior surgeons, with 68.7% eyes achieving a best-corrected visual acuity of ⩾6/12 (p = 0.17). No posterior capsular rupture, zonular dialysis or endophthalmitis was observed during the study period.

Conclusions:

This modified technique may serve as a useful transition technique for the phaco-trained surgeons to develop skills in manual small incision cataract surgery, with demonstrable good visual outcome and safety.

Are high-efficiency particulate air (HEPA) filters and laminar air flow necessary in operating rooms to control acute post-operative endophthalmitis?

Purpose

To compare the five-year incidence of acute post-operative endophthalmitis following cataract surgery, between centers with and without laminar air flow and high-efficiency particulate air (HEPA) filters in operating rooms.

Methods

Retrospective analysis of medical records of patients operated in a single network of a tertiary and four secondary hospitals across north India. Cases of endophthalmitis were identified from the records between January 2013 and June 2018. Protocols and consumables were standardized across all hospitals. The only infrastructural difference being the presence of laminar air flow and high energy particulate air filters in operating rooms of the tertiary center. The type of surgery, along with the demographic and socio-economic details, were captured and analyzed, using z-test for proportions and logistic regression.

Results

Out of 88,297 cataract surgeries conducted, 36 cases of endophthalmitis were reported. The incidence of endophthalmitis across the network was estimated to be 0.041%, (95% CI: 0.027 to 0.054). There was no statistically significant difference between the incidence of POE at the tertiary (0.042%) and secondary centers (0.039%). Certain risk factors for high endophthalmitis incidence were identified, namely patients undergoing small incision cataract surgery and belonging to lower socio-economic status. However, for both factors the difference was not statistically significant.

Conclusion

The five-year incidence of acute post-operative endophthalmitis in our network was found comparable to the best reported in literature. Incidence at secondary centers, without laminar air flow and high energy particulate air filters was found comparable to that in the tertiary center having these facilities.

Punctum and canalicular anatomy for hydrogel-based intracanalicular insert technology

Aim: Despite advances in cataract surgery, postoperative ocular inflammation and pain occurs. To address compliance issues with topical corticosteroid administration, a hydrogel-based dexamethasone insert was developed for intracanalicular administration. The objective is to understand the anatomy to best administer the insert and learn how the anatomy and hydrogel properties help retain the insert in the canaliculus over time. Materials & methods: Human cadavers (n = 5) were dissected to assess dimensions of punctum and canaliculus as part of drug discovery and development. Results & conclusions: Mean measures for punctal diameter was 0.5 ± 0 mm and vertical canaliculi length was 2.4 ± 0.5 mm and width was 1.6 ± 0.5 mm. Vertical canalicular width was larger than the punctal opening, a critical understanding for placing and retaining intracanalicular inserts.

Shortened cataract surgery by standardisation of the perioperative protocol according to the Joint Commission International accreditation: a retrospective observational study

OBJECTIVES

To investigate the impact of standardisation of the perioperative protocol based on the Joint Commission International (JCI) accreditation guidelines for operating time in cataract surgery.

DESIGN

Retrospective observational study.

SETTING

Single centre in Japan.

PARTICIPANTS

Between March 2014 and June 2016, 3127 patients underwent cataract surgery under topical anaesthesia including 2581 and 546 patients before and after JCI accreditation, respectively.

PRIMARY AND SECONDARY OUTCOMES

We compared three time periods, comprising the preprocedure/surgery time (pre-PT), PT and post-PT, and total PT (TPT) of cataract surgery between patients before and after JCI accreditation, by regression analysis adjusted for age, sex and cataract surgery-associated confounders.

RESULTS

The main outcomes were pre-PT, PT, post-PT and TPT. Pre-PT (19.8±10.5 vs 13.9±8.5 min, p<0.001) and post-PT (3.5±4.6 vs 2.6±2.1 min, p<0.001) significantly decreased after JCI accreditation, while PT did not significantly change (16.8±6.7 vs 16.2±6.3 min, p=0.065). Consequently, TPT decreased on average by 7.3 min per person after JCI accreditation (40.1±13.4 vs 32.8±10.9 min, p<0.001). After adjusting for confounders, pre-PT (β=-5.82 min, 95% CI -6.75 to -4.88), PT (β=-0.76 min, 95% CI -1.34 to -1.71), post-PT (β=-0.85 min, 95% CI -1.24 to -0.45) and TPT (β=-7.43 min, 95% CI -8.61 to -6.24) were significantly shortened after JCI accreditation.

CONCLUSION

Perioperative protocol standardisation, based on JCI accreditation, shortened TPT in cataract surgery under local anaesthesia.