Three-Dimensional Heads-up Cataract Surgery Using Femtosecond Laser: Efficiency, Efficacy, Safety, and Medical Education-A Randomized Clinical Trial

Light as a drug: prospective randomized evaluation and comparison of the effect of decreased illumination on visual recovery after cataract surgery

PURPOSE

To compare the effect of decreased illumination on the rate of postoperative visual recovery, and the incidence of cystoid macular edema (CME) with surgical visualization achieved with a traditional analog operating microscope compared with a 3D digital visualization system.

SETTING

Ambulatory surgery center, New York.

DESIGN

Prospective, randomized, consecutive, single-surgeon series.

METHODS

Patients undergoing routine cataract surgery were randomized into either (1) visualization through the binoculars of a standard operating microscope ("traditional group") or (2) visualization through a 3D digital visualization system affixed to the same operating microscope ("digital group"). Note was made in each case of light intensity used, light exposure time, cumulative dissipated energy (CDE), femtosecond laser use, preoperative medical and ocular conditions, intraoperative and/or postoperative complications, and preoperative and postoperative visual acuities and optical coherence tomography confirmed CME.

RESULTS

The study comprised 118 eyes in the traditional group and 96 eyes in the digital group. There were no differences in preoperative visual acuity, light exposure time, CDE, or femtosecond laser use between groups, but the light intensity used in the digital group was significantly less (19.5% ± 0.5%) than in the traditional group (48.6% ± 0.6%; P < .001). Furthermore, the digital group achieved a better decimal postoperative day 1 visual acuity (0.60 ± 0.03) with less rates of CME (2.1%) when compared with that of the traditional group (0.51 ± 0.02, P = .03; and 9.2%, P = .03), respectively.

CONCLUSIONS

Visual recovery and CME rates were significantly better in patients who underwent cataract surgery assisted by the 3D digital visualization platform without an increase in complications or surgical time.

Comparison of posterior capsule rupture rates during phacoemulsification using 3D heads-up visualization system and traditional microscopes

PURPOSE

To compare the posterior capsule rupture (PCR) rates of cataract surgery using a traditional ophthalmic surgical microscope (OSM) and a 3D heads-up visualization system (HUVS).

SETTING

Single tertiary referral center.

DESIGN

Retrospective study.

METHODS

This study included 10 101 eyes that underwent phacoemulsification cataract surgery. Surgeries were performed using either 3D HUVS (1964 eyes, performed by 2 surgeons, HUVS group) or traditional OSM (8137 eyes, performed by 6 surgeons, OSM group) from February 2018 to June 2022. Data were collected based on the diagnosis-related group system, and the rate of PCR requiring vitrectomy and the surgical time were evaluated.

RESULTS

The PCR rates were not significantly different between the OSM (n = 63; 0.7%) and HUVS (n = 19; 0.9%, P = .392) groups. The mean surgical time was significantly longer in the HUVS group (14.7 ± 10.6 minutes) than in the OSM group (12.9 ± 9.9 minutes, P < .001). In the 3D HUVS group, there were no PCR cases among the initial 100 patients. In both groups, no significant difference was observed in the PCR rates over time. Although the difference was not statistically significant, the PCR rate decreased over time in the HUVS group.

CONCLUSIONS

The results indicate that 3D HUVS-based cataract surgery performed by experienced cataract surgeons had a PCR rate similar to that of traditional OSM-based surgery during the 4-year study period. Although the surgical time was slightly longer with 3D HUVS, cataract surgery using 3D HUVS can be performed safely by experienced surgeons.

Comparison of three-dimensional heads-up system versus traditional microscopic system in medical education for vitreoretinal surgeries: a prospective study

BACKGROUND

To compare the value and efficiency of the three-dimensional (3D) heads-up surgical system and traditional microscopic (TM) system in teaching and learning vitreoretinal surgeries.

METHODS

Twenty ophthalmologists and scrub nurses were recruited as teachers, and 45 junior ophthalmology residents and trainee doctors, trainee nurses, and medical students were recruited as observers. Each teacher and observer were assigned to both a 3D-assisted and TM-assisted vitreoretinal surgery and then asked to complete satisfaction questionnaires for both surgical systems at the end of each surgery.

RESULTS

The 3D heads-up surgical system was rated significantly higher in most of the subscales and overall satisfaction score by both teachers and observers (P < 0.05). However, ratings for instrument adjustment were significantly higher in the TM group compared to the 3D group for junior ophthalmology residents and trainee doctors (6.1 ± 1.7 vs. 8.8 ± 1.1, P < 0.001).

CONCLUSIONS

The 3D heads-up surgical system has great didactical value in the medical education of vitreoretinal surgeries, but it is important to consider the specific needs of different learners when choosing between the two systems.

TRIAL REGISTRATION

Not applicable.

Quality assessment and comparison of two- and three-dimensional YouTube videos as additional educational tools for cataract surgery: "METAVERSE"

BACKGROUND

To compare the content and quality of 3D YouTube videos with 2Ds as additional educational tools for phacoemulsification surgery.

METHODS

This cross-sectional study included 2D and side-by-side 3D phacoemulsification videos found on YouTube by searching for "phacoemulsification," "phaco," and "cataract." Data was collected on video length (min), time since upload (days), number of views, likes, dislikes, cataract type, chop technique, and visualization system. Video popularity and interaction were calculated by video power index, interaction index, and viewing rate. Two senior ophthalmologists (SOs) and two ophthalmology residents (ORs) evaluated videos using the DISCERN, global quality score (GQS), and usefulness scoring systems. Inter-rater reliability was assessed using intra-class correlation coefficient (ICC).

RESULTS

A total of 457 videos were screened, with 85 in 2D and 85 in 3D deemed appropriate for analysis. 2D videos received significantly more views, likes, dislikes, days since upload, video power index, and viewing rate than 3Ds (p < 0.001). Video length and interaction index in 3D videos were significantly greater than in 2Ds (p < 0.001). All video scoring systems revealed that 3D videos outperformed 2Ds in ORs (p < 0.05). ICC confirmed good inter-rater reliability agreement even at the lowest value (SOs: 0.924, 95% CI, 0.910-0.937; ORs: 0.892, 95% CI, 0.878-0.908).

CONCLUSIONS

3D YouTube videos as additional educational tools could help not only SOs but also ORs fully comprehend the breadth and depth of ocular surgeries, particularly phacoemulsification, by improving depth perception. They can also be used to review previously learned procedures, observe new ones, and recall old ones.

The Implementation of Glasses-free 3D Display in ICL Surgery: A Pilot Study

PURPOSE

To compare the efficacy and safety of the glasses-free three-dimensional (3D) display and conventional optical microscope in Implantable Collamer Lens (ICL; STAAR Surgical) surgery.

METHODS

This randomized controlled trial enrolled 51 eyes of 26 patients who received ICL surgery. After random allocation, patients received surgery under either a glasses-free 3D display (16 eyes) or a conventional optical microscope (35 eyes). The surgical duration, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), intraocular pressure, vault, postoperative manifest refraction spherical equivalent (MRSE), and complications were evaluated.

RESULTS

Mean surgical time was 5.04 ± 2.74 minutes for the glasses-free 3D group and 4.65 ± 2.63 minutes for the conventional microscope group (P = .639). Postoperative UDVA was -0.02 ± 0.04 and -0.04 ± 0.05 logMAR (P = .169), CDVA was -0.03 ± 0.04 and -0.02 ± 0.05 logMAR (P = .434), and IOP was 17.01 ± 3.15 and 14.82 ± 2.20 mm Hg (P = .055) at 1 month of follow-up, respectively. Vault was 562.86 ± 192.89 and 520.18 ± 215.19 µm, and MRSE was +0.25 ± 0.21 and +0.10 ± 0.51 diopters, respectively, at 1 month postoperatively; all were comparable between the glasses-free 3D group and conventional microscope group (all P > .05). No complication occurred in both groups.

CONCLUSIONS

The glasses-free 3D group achieved similar efficacy and safety compared to the conventional microscope group, and glasses-free 3D surgery is expected to show a significant advantage in clinical and medical education. [J Refract Surg. 2023;39(9):612-619.].

Evolution of operating microscopes and development of 3D visualization systems for intraocular surgery

The recent development of high-resolution, heads-up, 3D visualization microscopy systems has provided new technical and visualization options for ophthalmic surgeons. In this review, we explore the evolution of microscope technologies, the science behind modern 3D visualization microscopy systems, and the practical benefits (as well as disadvantages) that these systems provide over conventional microscopes for intraocular surgical practice. Overall, modern 3D visualization systems reduce the requirements for artificial illumination and provide enhanced visualization and resolution of ocular structures, improving ergonomics, and facilitating a superior educational experience. Even when considering their disadvantages, such as those related to technical feasibility, 3D visualization systems have an overall positive benefit/risk ratio. It is hoped these systems will be adopted into routine clinical practice, pending further clinical evidence on the benefits they may provide on clinical outcomes.

Three-Dimensional Visualization System for Vitreoretinal Surgery: Results from a Monocentric Experience and Comparison with Conventional Surgery

PURPOSE

To describe the experience of our centre (Careggi University Hospital, Florence, Italy) in using a heads-up three-dimensional (3D) surgical viewing system in vitreoretinal surgery, making a comparison with the conventional microscope surgery.

METHODS

We retrospectively analyzed data taken from 240 patients (240 eyes) with surgical macular diseases (macular hole and epiretinal membrane), retinal detachment or vitreous hemorrhage who underwent vitreoretinal surgeries, by means of the NGENUITY 3D Visualization System (Alcon Laboratories Inc., Fort Worth, TX, USA), in comparison with 210 patients (210 eyes) who underwent vitreoretinal surgeries performed using a conventional microscope. All surgeries were performed with standardized procedures by the same surgeons. We analyzed data over a follow-up period of 6 months, comparing the surgical outcomes (best-corrected visual acuity, anatomical success rate and postoperative complication rate) between the two groups.

RESULTS

the 3D group included 74 patients with retinal detachment, 78 with epiretinal membrane, 64 with macular hole and 24 with vitreous hemorrhage. There were no significant differences in the demographic and clinical characteristics between the 3D group and the conventional group. We found no significant differences in outcome measures at three and six months follow-up between the two groups (p-value ≥ 0.05 for all comparisons). Surgery durations were similar between the two groups.

CONCLUSIONS

In our experience, a heads-up 3D surgical viewing system provided comparable functional and anatomical outcomes in comparison with conventional microscope surgery, proving to be a valuable tool for vitreoretinal surgery in the treatment of different retinal diseases.

Three-dimensional heads-up system assisted pars plana vitrectomy and subretinal recombinant tissue plasminogen activator injection for submacular hemorrhage

BACKGROUND

To evaluate the outcomes of three-dimensional (3D) heads-up system assisted pars plana vitrectomy (PPV) and subretinal injection of recombinant tissue plasminogen activator (rt-PA) for submacular hemorrhage (SMH).

METHODS

Medical records of SMH patients who underwent 3D heads-up system assisted-PPV and subretinal injection of rt-PA from June 2021 to January 2022 were reviewed. The main outcomes included best-corrected visual acuity (BCVA), SMH absorption, and perioperative complications.

RESULTS

We finally included 18 SMH eyes, most of which happened secondary to polypoidal choroidal vasculopathy (PCV) (10, 55.56%), followed by retinal arterial microaneurysm (RAM) (5, 27.78%), traumatic retinopathy (2, 11.11%) and neovascular age-related macular degeneration (nAMD) (1, 5.56%). The greatest linear dimension (GLD) and height of SMH were 6538.17 ± 2533.11 μm and 937.36 ± 420.21 μm, respectively. After an average postoperative follow-up period of 131.06 ± 38.96 days, patients' BCVA improved significantly from 1.85 ± 0.62 to 1.14 ± 0.82 logMAR (P < 0.05). SMH was completely and partially absorbed in 9 (50.00%) and 6 (33.33%) eyes, with no occurrence of iatrogenic retinal break. However, 4 additional PPVs were performed to manage the postoperative SMH and/or vitreous hemorrhage (VH) recurrence (2, 11.11%) and retinal detachment (RD) occurrence (2, 11.11%). Preoperative BCVA was significantly correlated with postoperative BCVA in multiple linear regression analysis (P < 0.05), and hemorrhagic pigment epithelial detachment (PED) was significantly correlated with SMH and VH recurrence in univariate binary logistic regression analysis (P < 0.05).

CONCLUSIONS

The 3D heads-up system assisted-PPV and subretinal injection of rt-PA were efficacious in eliminating SMH and improving visual prognosis with satisfactory safety profile, while caution should be taken for PCV patients with hemorrhagic PED and massive SMH.

Three-Dimensional Heads-up Display in Cataract Surgery: A Review

Intraocular visualization in cataract surgery is currently achieved using the ophthalmic surgical microscope (OSM). Three-dimensional (3D) heads-up display is a burgeoning intraocular visualization technique for cataract surgery, which projects the surgical view to a 3D monitor. A number of theoretical advantages of this system over the OSM have been proposed. 3D visualization is reported to provide improved depth perception and the heads-up display promotes a more ergonomic surgical position while providing an enhanced view for the entire surgical team. The modern OSMs, however, already allow for safe and efficient cataract surgery, and 3D heads-up display visualization is limited by a steep learning curve. We critically review the literature around 3D heads-up display cataract surgery and compare its safety profile to traditional visualization techniques.

Three-Dimensional Heads-Up vs. Standard Operating Microscope for Cataract Surgery: A Systematic Review and Meta-Analysis

Background: The surgical time duration, the postoperative best-corrected visual acuity (BCVA), and the incidence rate of intraoperative complications, alongside the vision and posturing parameters, were estimated by systematic review and meta-analysis to compare the three-dimensional (3D) heads-up visualization system (HUVS) and standard operating microscope (SOM) in cataract surgery. Methods: A literature search was conducted using PubMed, Embase, and Scopus on 26 June 2022. The weighted mean difference (WMD) was used to present postoperative BCVA and the mean surgical time duration, whereas the risk ratio (RR) was used to present the incidence rate of intraoperative complications. Publication bias was evaluated with Egger’s test. The Cochrane Collaboration’s Tool for randomized clinical trials, the methodological index for non-randomized, and the Newcastle-Ottawa Scale were used to assess the risk of bias. The research has been registered with the PROSPERO database (identifier, CRD42022339186). Results: In the meta-analysis of five studies with 1021 participants, the pooled weighted mean difference (WMD) of the postoperative BCVA showed no significant difference between patients who underwent HUVS versus SOM cataract surgery (WMD = −0.01, 95% confidence interval (CI): −0.01 −0.02). In the meta-analysis of nine studies with 5505 participants, the pooled WMD of mean surgical time duration revealed no significant difference between patients who underwent HUVS versus SOM cataract surgery (WMD = 0.17, 95% CI: −0.43–0.76). In the meta-analysis of nine studies with 8609 participants, the pooled risk RR associated with intraoperative complications was 1.00 (95% CI, 1.00–1.01). Conclusions: 3D HUVS and SOM provide comparable surgical time duration, postoperative BCVA, and incidence rate of intraoperative complications.

Comparison of Three-Dimensional Surgical System Versus Binocular Microscope for Clear Corneal Incision in Cataract Surgery

INTRODUCTION

To compare surgical outcomes of 2.2 mm clear corneal incision (CCI) between a three-dimensional (3D) visualization system and traditional binocular microscope (BM) for phacoemulsification and intraocular lens implantation surgery.

METHODS

In this randomized controlled clinical study, 60 eyes with age-related cataracts were divided into two groups receiving cataract surgery using either a 3D vision system (n = 30 eyes) (3D group) or a binocular microscope (n = 30 eyes) (BM group). We recorded and statistically analyzed surgical parameters and pre- and postoperative ocular parameters. Primary outcomes included the change in endothelial cell density (ECD) and CCI architecture, and secondary outcomes comprised other ocular parameters and surgical parameters. All procedures complied with the tenets of the Declaration of Helsinki.

RESULTS

Of the 60 eyes randomly assigned between January 5, 2021, and May 9, 2021, 55 (26 eyes in the 3D group and 29 eyes in the BM group) were analyzed. The ECD loss rate was 8.1% in the 3D group and 12.3% in the BM group, but the difference was not statistically significant. Local detachment of Descemet's membrane was seen in 50% (13 eyes, 3D group) and 51.6% (15 eyes, BM group), wound gaping at the endothelial side in 15.4% (four eyes, 3D group) and 10.3% (four eyes, BM group), gaping at the epithelial side in 11.5% (three eyes, 3D group) and 6.9% (two eyes, BM group), and misalignment of the incision in 3.4% (one eye, BM group) 1 day after surgery. These abnormalities improved with time. There was no difference between the 3D group and BM group in terms of other ocular parameters or surgical parameters before and after surgery.

CONCLUSIONS

Using the 3D surgical system for phacoemulsification and IOL implantation surgery seems to result in similar ECD and CCI conditions as using a conventional binocular microscope.

TRIAL REGISTRATION

The protocol was registered on ClinicalTrials.gov (NCT04839250).

Active-fluidics versus gravity-fluidics system in phacoemulsification for age-related cataract (AGSPC): study protocol for a prospective, randomised, double-blind, controlled clinical trial

INTRODUCTION

The active-fluidics system is a new irrigation system of phacoemulsification that automatically detects and maintains stable intraocular pressure at the set value. This trial is designed to compare the efficacy, visual outcomes, safety and patients' subjective perceptions of cataract surgery with the active-fluidics system and gravity-fluidics system.

METHODS AND ANALYSIS

This trial will recruit 110 patients with age-related cataract at the Chinese People's Liberation Army (PLA) General Hospital (Beijing, China) and they will be randomly assigned to the active-fluidics group and gravity-fluidics group in a ratio of 1:1 to have phacoemulsification. Patients will be followed up at 1 day, 1 week, 1 month and 3 months postoperatively. The primary outcomes are the cumulative dissipated energy and best corrected visual acuity. Secondary outcomes include: estimated fluid usage, U/S time, total aspiration time, intraocular pressure, corneal endothelium parameters, retinal thickness, macular superficial vessel density, pain scores, scores of the Cataract surgery Patient-Reported Outcome Measures Questionnaire and the complication rates. The data will be independently analysed by the statistical team, who will be masked for the allocation information as participants are.

ETHICS AND DISSEMINATION

This study was approved by the Ethics Committee of Chinese PLA General Hospital (approval no. S2021-068-01). Informed consent will be obtained from each participant. All the results will be published in peer-reviewed journals and used for scholarly communication or technical guidance. Protocol version 1.0.

TRIAL REGISTRATION NUMBER

Chinese Clinical Trial Registry (ChiCTR2100044409).