Multicenter Evaluation of Time, Operational, and Economic Efficiencies of a New Preloaded Intraocular Lens Delivery System versus Manual Intraocular Lens Delivery

In vivo comparison of implantation behavior and laboratory analysis of two preloaded intraocular lens injectors

PURPOSE

We evaluated implantation behavior and injector damage of two different IOL injector systems, the Multisert and the AutonoMe.

DESIGN

Prospective, randomized, comparative study with laboratory investigation.

METHODS

We examined used injectors from 48 bilateral cataract cases and assessed video recordings of each Implantation. All eyes were intraindividually randomized for treatment with one of the two IOL injectors. Implantation videos were reviewed for inadvertent events and the time for different implantation steps was determined. The injector nozzle tips were examined using light and scanning electron microscopy (SEM). Damage was graded using the Heidelberg Score for IOL injector damage (HeiScore). Three months postoperatively, IOLs were assessed for material changes.

RESULTS

Implantation was without critical events in 96 of 96 eyes. Mean implantation time was 41.90 ± 7.11 s with the Multisert and 52.22 ± 12.06 s with the AutonoMe. In the AutonoMe group, we observed 4 eyes (8.3%) with a failed docking attempt, 28 eyes (58.3%) with a haptic adherence, one case (2.1%) of straight leading haptic and 2 cases (4.2%) of intrawound IOL manipulation. There were no events observed in the Multisert group. The mean HeiScore values were 0.87 ± 0.61 and 3.68 ± 0.47 for the AutonoMe and Multisert. 3 months postoperatively, IOL material changes were absent.

CONCLUSIONS

Both injectors allowed safe and controlled implantation. Using Multisert, implantation behavior was more consistent. The injectors showed different damage profiles with a higher damage score for the Multisert.The study is registered at the German Clinical Trials Register (Deutsches Register Klinischer Studien; reference number: DRKS00007837).

Clinical Evaluation of a Hydrophobic Intraocular Lens Using a Preloaded Automated Injector in a Korean Population

Purpose

This study assessed post-market clinical outcomes of the Clareon monofocal intraocular lens (IOL) preloaded in the AutonoMe Delivery System in a real-world setting of Korean patients.

Methods

This prospective, multicenter, single-arm study in Korea was conducted from July 2020 to December 2021. Patients were ≥20 years old with unilateral or bilateral cataracts who received Clareon IOLs (CNA0T0) preloaded in an automated injector system. Best corrected distance visual acuity (BCDVA) and uncorrected distance visual acuity (UCDVA) were evaluated under photopic conditions. Surgeon delivery system preference was assessed using a survey questionnaire. Glistenings, surface haze, adverse events, posterior capsule opacification (PCO), and Nd:YAG capsulotomy rates were also assessed during the 12-month postoperative follow-up.

Results

Mean ± SD monocular BCDVA was 0.02 ± 0.11 and 0.00 ± 0.10 logMAR at 1 month and 12 months, respectively. BCDVA of 0.2 logMAR or better was achieved by 94.4% and 99.1% of eyes at 1 month and 12 months after implantation, respectively. Mean monocular UCDVA was 0.11 ± 0.14 and 0.07 ± 0.13 logMAR at 1 month and 12 months, respectively. UCDVA of 0.3 logMAR or better was achieved by 97.4% of eyes at 12 months after implantation. Preparation of the automated injector system was rated as "very easy" or "easy" and CNA0T0 IOL delivery was rated as "very controllable" or "controllable" by all surgeons. Only grade 0 glistenings and no surface haze were observed during the 12-month follow-up. No clinically significant PCO or Nd:YAG capsulotomy were reported throughout the study; clinically nonsignificant PCO was reported in 23% of eyes.

Conclusion

This 12-month real-world study of the CNA0T0 IOL and the automated injector system demonstrated excellent visual outcomes and high surgeon satisfaction.

Nano-Indentation to Determine Mechanical Properties of Intraocular Lenses: Evaluating Penetration Depth, Material Stiffness, and Elastic Moduli

INTRODUCTION

Intraocular lenses (IOL) should remain in the eye for life after implantation into the capsular bag during cataract surgery. The material must meet various requirements. It is crucial that the material has the best biocompatibility, and it should be flexible and soft for best possible implantation process but also sufficiently stable and stiff for good centering in the eye and posterior capsule opacification prevention.

METHODS

In this laboratory experiment, we used nano-indentation for the mechanical assessment of three hydrophobic acrylic (A, B, C), three hydrophilic acrylic (D, E, F), and one silicone (G) intraocular lens. We wanted to determine whether some react more sensitively to touching/handling than others. The indentation elastic modulus and the creep were obtained from the force displacement curve. For measuring penetration depth and testing of possible damage to the intraocular lenses, the samples were measured at room temperature. A 200-µm-diameter ruby spherical tipped indenter was used for all the tests. Indentations were made to three different maximum loads, namely 5 mN (milli Newton), 15 mN, and 30 mN and repeated three times.

RESULTS

The lowest penetration depth (12 µm) was observed with IOL B. However, IOL A, D, and F showed similar low penetration depths (20, 18, and 23 µm, respectively). Lenses C and E showed slightly higher penetration depths of 36 and 39 µm, respectively. The silicone lens (G) showed the greatest penetration depth of 54.6 µm at a maximum load of 5 mN. With higher maximal loads (15 and 30 mN) the penetration depth increased significantly. Lens C, however, showed the same results at both 15 and 30 mN with no increase of penetration depth. This seems to fit well with the material and manufacturing process of the lens (lathe-cut). During the holding time of 30 s at constant force all six acrylic lenses showed a significant increase of the creep (CIT 21-43%). Lens G showed the smallest creep with 14%. The mean indentation modulus (EIT) values ranged from 1 to 37 MPa. IOL B had the largest EIT of 37 MPa, which could be caused by the low water content.

CONCLUSION

It was found that results correlate very well with the water content of the material in the first place. The manufacturing process (molded versus lathe-cut) seems to play another important role. Since all included acrylic lenses are very similar, it was not surprising that the measured differences are marginal. Even though hydrophobic materials with lower water content showed higher relative stiffness, penetration and defects can also occur with these. The surgeon and scrub nurse should always be aware that macroscopic changes are difficult to detect but that defects could theoretically lead to clinical effects. The principle of not touching the center of the IOL optic at any time should be taken seriously.

Preferred cataract surgery practices in Malaysia: a survey based study

BACKGROUND

To describe the preferred cataract surgery practices among Malaysian ophthalmologists and medical officers in comparison with the recommended practices.

METHODS

An online questionnaire was sent out in April 2021, to Malaysian Ophthalmologists and medical officers who perform cataract surgeries. The questions were focused on the preferred cataract surgery practices of the participants. All data obtained were collected, tabulated and analysed.

RESULTS

A total of 173 participants responded to the online questionnaire. 55% of the participants were within 31-40 years of age. 56.1% preferred peristaltic pump over venturi system. 91.3% of participants practised povidone iodine instillation to the conjunctival sac. With regards to the main wound incision, more than half of the surgeons (50.3%) preferred fixed superior incision and 72.3% of them preferred 2.75 mm microkeratome blade. Most of the participants (63%) were inclined towards C-Loop clear intraocular lens (IOL) with a single-handed push preloaded system. 78.6% of the surgeons routinely use carbachol in their cataract surgery.

CONCLUSIONS

This survey provides some insight into the current practices among Malaysian ophthalmologists. Most of the practices are in line with international guidelines for preventing postoperative endophthalmitis. This article could help trainees and ophthalmologists benchmark and observe the common cataract surgery practices among their seniors and peers in Malaysia.

The impact of preloaded intraocular lens implantation system (TECNIS iTec®) in routine cataract surgery in China: a time-motion analysis

OBJECTIVE

To evaluate the impact on surgical efficiency and labor time cost of preloaded intraocular lens (IOL) implantation system compared with manual IOL implantation system in age-related cataract surgery in China.

METHODS

This study was an observational, multicenter, prospective time-motion analysis. IOL preparation time, operation time, cleaning time, number and cost of cataract surgeries in eight participating hospitals were collected. The linear mixed model was used to explore factors associated with the difference in operation time between the preloaded IOL implantation system and the manual IOL implantation system. A time-motion model was constructed to convert the operation time cost saved by using preloaded IOL into economic benefits from hospital and social perspective, respectively.

RESULTS

There were 2,591 cases included in the study (preloaded IOL: 1,591 cases; manual IOL: 1,000 cases). The preloaded IOL implantation system was significant time-saving in both preparation time and operation time compared to the manual IOL implantation system (25.48s vs. 47.04s, P < 0.001 and 353.84s vs. 367.46s, P = 0.004, respectively). An average total of 35.18s can be saved by using preloaded IOL per procedure. The results of linear mixed model showed that the type of IOL was the main factor leading to the difference in preparation time between preloaded IOL and manual IOL implantation system. By switching from manual IOL to preloaded IOL, the model projected additional 392 surgeries can be performed each year and an increase in revenue of $565,282 per hospital, a 9% increase from hospital perspective. And the annual productivity loss saved by using preloaded IOL was $3,006 in eight hospitals from perspective of society.

CONCLUSION

Compared with manual IOL implantation system, the preloaded IOL implantation system reduces lens preparation time and operation time, which increases potential surgical volume and revenue, and reduces the loss of work productivity. This study provides real-world evidence to support the advantages of the preloaded IOL implantation system in improving efficiency of ophthalmic surgery in China.

CONTEMPORARY PRACTICES IN CATARACT SURGERY - SUBJECTIVE PREFERENCES OF CZECH CATARACT SURGEONS

AIMS

The aim of the work was to find out the current subjective preferences of Czech cataract surgeons in terms of individual procedures, techniques and materials used during cataract surgery.

MATERIAL AND METHODS

This study was conducted in the form of a questionnaire (online, a total of 44 questions). The survey respondents were members of the Czech Society of Refractive and Cataract Surgery. Questions 1-10 concerned the characteristics of the respondent (age, number of operations performed, type of workplace, etc.). Questions 11-20 focused on the surgical procedure used by the specific surgeon (anaesthesia, viscomaterial, position of the main incision, use of antibiotics at the end of the operation, etc.). Questions 21-34 concerned the type of intraocular lens used. Lastly, in questions 35-44, respondents were asked about their individual preferences if cataract surgery were to be performed on them.

RESULTS

The questionnaire was fully or partially completed by 72 surgeons (26% of the originally approached subjects). Most of the respondents were experienced surgeons, 74.5% of them have been performing surgeries for more than 10 years, out of which 55.5% perform more than 500 operations per year. The average age of the respondents was 50 years. 65.3% of surgeons use hydroxypropylmethylcellulose during surgery, 74% do not use a femtosecond laser for surgery, 50% never perform posterior circular capsulorhexia, and 98% apply antibiotics to the anterior chamber at the end of surgery. Surgeons predominantly use hydrophobic (80.8%), aspherical (72.3%), clear (54.3%), single-focal (97.9%) and non-preloaded (78.3%) lenses. However, if they were not limited or restricted in any way in their choice, they would prefer aspherical lenses (94.6%), multifocal or extended-focus lenses (78%) and preloaded lenses (96.8%).

CONCLUSION

The subjective preferences of Czech cataract surgeons are relatively variable regarding the individual steps. Often the procedures used do not always correspond with the actual preferences of the surgeon. On the contrary, there is almost complete unity in the steps recommended by professional societies (intracameral antibiotics at the end of the operation).