Comparison of microscopic illumination between a three-dimensional heads-up system and eyepiece in cataract surgery

Relationship between Image Quality and Reproducibility of Surgical Images in 3D Digital Surgery

Objectives: Ophthalmic three-dimensional (3D) digital surgery can reproduce high-definition surgical images; however, 3D digital surgery is limited by recording capacities. We examined the relationship between the minimum image quality required to reproduce surgical images and recording capacity. Methods: Patients who underwent simultaneous vitrectomy and cataract surgery by the same surgeon using a 3D digital surgery system at Juntendo University Urayasu Hospital between February and October 2021 were evaluated. Various quality (Q) and frame rate (FR) settings were used for each case. Four vitreous surgeons evaluated the reproducibility of recorded images of macular manipulation for epiretinal membrane (ERM) and macular hole (MH) cases and those of peripheral retinal manipulation for rhegmatogenous retinal detachment (RRD) cases. The video bitrate and minimum settings required to reproduce surgical images and factors affecting surgical image reproducibility were examined. Results: A total of 129 eyes of 129 patients were observed. The minimum image quality required to reproduce surgical images was 11.67 Mbps. The Q and FR for periretinal processing and Q for macular manipulation affected surgical image reproducibility (p = 0.025, p = 0.019, and p = 0.07, respectively). The minimum recording settings required to obtain highly reproducible images were Q = 3 and FR = 40. The total file size for vitrectomy video recordings with these settings was as compact as 3.17 GB for 28 min. Conclusions: During 3D digital surgery, highly reproducible surgical images can be obtained with a small storage capacity using settings of at least Q = 3 and FR = 40.

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.

Application of three-dimensional visualization technology in phacoemulsification benefits the dry eye symptoms of patients after cataract surgery

Purpose

To investigate the effects of the three-dimension visualization system on dry eye in patients after cataract phacoemulsification.

Methods

Seventy-one patients (104 eyes) were enrolled in this study and assigned to the conventional microscopic group (CM group) or three-dimension group (3D group). Ocular Surface Disease Index, The Schirmer I test (SIt), lipid layer thickness (LLT), noninvasive tear breakup time (NIBUT) and other factors associated with dry eye were recorded before and 1 week and 1 month after surgery. The operation time and intraoperative light intensity (ILI) were also recorded.

Results

The ILI in the 3D group was significantly lower than that in the CM group (33% vs. 60%, p < 0.01). There was an interaction (group and time) effect for first NIBUT (NIBUT-F), average NIBUT (NIBUT-Ave), tear meniscus height (TMH) and the score of eye redness (Pinteraction < 0.05). The main effects of group on SIt, LLT, NIBUT-F, NIBUT-Ave and the score of eye redness were significant (Pgroup < 0.05). In the CM group, SIt, LLT, NIBUT-F, NIBUT-Ave, TMH were lower than those of the 3D group, the score of eye redness was higher than that of the 3D group at 1 week and 1 month after surgery (all p < 0.05). The changes in NIBUT-F and NIBUT-Ave between before surgery and 1 week after surgery showed negative correlations with ILI (p < 0.01).

Conclusion

Compared with microscopic surgery, the 3D visualization system can provide better tear film stability for patients after cataract surgery.

3D visualization system and standard operating microscope for ease of visualization and surgeon comfort during phacoemulsification surgery

PURPOSE

To compare the ease of visualization and comfort of the surgeon during phacoemulsification surgery using NGENUITY® 3D (NG) visualization system and standard operating microscope (SOM).

METHODS

In this prospective, randomized, single-blind, single-center study, patients undergoing phacoemulsification surgery by one of the five surgeons were randomly assigned to two groups based on the visualization modality-NG and SOM. Ease of visualization and comfort of the surgeon was assessed using a 27-parameter in-house Surgeon Comfort Score questionnaire.

RESULTS

A total of 224 phacoemulsification with intraocular lens implantations were performed in senile immature cataract (SIMC, n = 174) and mature cataract patients (MC, n = 50). Surgeon's ease of visualization (4.92-5.00) and hand-eye coordination score (4.97-5.00) were comparable between the NG- and SOM-groups. Postoperative neck discomfort was lower in both the groups, with a relatively lower discomfort in the NG-group (score: 1.04 vs 1.56). The Spearman rank correlation coefficient (r) between illumination of the operation theatre room and the surgical field revealed a weak negative correlation for most of the patients in the NG-group, and a positive correlation for patients in the SOM-group. No correlation was obtained between brightness of the surgical field and comfort with the surgical field brightness.

CONCLUSIONS

Similar ease of visualization was experienced by the surgeons using NG- and SOM-system. Neck discomfort postsurgery was numerically lower in the NG-group, although not significant. Additionally, the NG-system permitted the safe performance of phacoemulsification using a lower surgical field illumination.

Use of a three-dimensional head-mounted digital visualization platform in cataract surgery

OBJECTIVE

To report preliminary experience using the BeyeonicsOne (Beyeonics Vision, Haifa, Israel) digital visualization platform and the utilization of its three-dimensional (3D) head-mounted display (HMD) in cataract surgery.

METHODS

An interventional case series including patients who underwent cataract surgery using the 3D HMD platform at the Tel Aviv Medical Center. The system uses the HMD unit to display high-resolution real-time 3D surgical field images. Collected data included patient demographics, ocular comorbidities, risk factors for complex cataract surgery, cataract grading, preoperative and postoperative best-corrected visual acuity (BCVA), and intra- and postoperative complications.

RESULTS

In total, 60 eyes of 60 subjects (mean age 73.1 ± 8.4 years) were included. Mean preoperative BCVA was 0.40 ± 0.30 logMAR (Snellen equivalent ~20/50) and improved to 0.10 ± 0.10 logMAR (Snellen equivalent ~20/25, p < 0.001). None of the patients suffered BCVA loss. All procedures and follow-ups were uneventful except for one case of a posterior capsular tear and one case of post-surgical cystoid macular edema.

CONCLUSION

The visualization platform and its embedded 3D head-mounted display can be easily used in routine cataract surgery with the added benefits of improved ergonomics, high picture quality and enhanced image control.

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.

Evaluation of new approach to enhance visualization performance in cataract surgery: 3D visualization system with coaxial illumination

PURPOSE

To evaluate the visualization performance of different approaches, including the 3D visualization system with coaxial illumination and the 3D system or microscope with standard illumination.

SETTING

Fuzhou Eye Hospital, Fuzhou City, China.

DESIGN

Cross-sectional study.

METHODS

This 2-part performance assessment for visualization composed of an objective analysis using surgical video images and a subjective survey collecting feedback from surgeons. Data of each eye were obtained with 3 approaches: standard operating microscope with standard illumination (SOM-S), 3D visualization system with standard illumination (3D-S), and 3D visualization system with coaxial illumination (3D-C).

RESULTS

112 eyes (107 cases) and 6 cataract surgeons were involved. The red reflex value was markedly greater in the 3D-C approach compared with other 2 approaches ( P < .001). Compared with the SOM-S approach, the red reflex increased by 55%, 57%, and 53% in the 3D-C approach, corresponding to nuclear grades of II, III, and IV, respectively. In the questionnaire survey, red reflex scores were consistently significantly higher in the 3D-C approach than those in the others ( P < .001). Depth of field was enhanced in both 3D approaches compared with the SOM-S approach ( P < .05). The only minor advantage of the SOM system over the 3D-C approach was in the surrounding field clarity score, and the difference was not statistically significant ( P = 1.000).

CONCLUSIONS

The 3D-C approach significantly increased the red reflex in both objective and subjective assessments. Surgeon responses also showed a superior performance for the 3D-C approach.

Magnification and Refocusing Comparison in Cataract Surgery Using a Heads-Up Three-Dimensional Visualization System versus Conventional Binocular Microscopy

Purpose

To compare magnification and refocusing during phacoemulsification with the NGENUITY® 3-D Visualization System (3-D) versus the conventional microscope (CM) OPMI LUMERA 700.

Setting

This study was performed in the Department of Anterior Segment of the Fundación Hospital Nuestra Señora de la Luz.

Design

Prospective, randomized, cross-sectional, multi-surgeon, and comparative study.

Methods

This study enrolled 100 patients (eyes) scheduled for phacoemulsification to measure the number of times changes in focusing and magnification were needed during cataract surgery.

Results

Our study included 100 patients. From the endpoints evaluated, "zoom-in" showed statistically significant differences for all of the four predefined cataract surgery steps (means: Step 1, 0.38 (CM) vs 0.08 (3-D); Step 2, 0.36 (CM) vs 0.06 (3-D); Step 3, 0.54 (CM) vs 0.22 (3-D); Step 4, 0.56 (CM) vs 0.24 (3-D); all comparisons, p <0.05). In Step 4, there was a statistically significant increased use of "focus-out" for the 3-D system (mean 0.16 (CM) vs 0.58 (3-D); p <0.05). "Focus-in" and "zoom-out" showed no group differences for all steps. The duration of surgery with the 3-D system was longer at each step and overall. The percentage of light intensity did not show a statistically significant difference between both systems, with a mean of 99.45 for CM vs 98.43% for the heads-up system.

Conclusion

The heads-up 3-D system is a safe option that offers excellent magnification for anterior segment visualization. The surgical time is longer, but adjusting settings like light intensity and brightness may facilitate some surgical steps early in the learning curve.

Comparing microscope light-associated glare and comfort between heads-up 3D digital and conventional microscopes in cataract surgery: a randomised, multicentre, single-blind, controlled trial

OBJECTIVE

To compare subjective levels of comfort and visual experiences related to microscope light in patients undergoing their first cataract surgery with topical anaesthesia using a digital microscope (the NGENUITY three-dimensional (3D) visualisation system) or a conventional microscope.

METHODS AND ANALYSIS

A prospective, randomised, single-blinded, parallel-group, multicentre, interventional study. Patients (n=128) were randomly assigned to one of two treatment groups: the experimental group (n=63) had surgery using the digital microscope and the control group (n=65) had surgery with a conventional microscope. The primary outcome was patients' subjective experience of glare from the microscope light during surgery on a numerical scale from 0 to 10. Key secondary outcomes were patients' subjective levels of comfort and visual experiences related to the microscope light.

RESULTS

The experimental group reported significantly lower levels of glare; median levels were 1.0 (0.0-4.0) for the experimental group vs 3.0 (0.0-6.0) for the control group (p=0.027). They also reported higher levels of comfort; median ratings were 8.0 (6.5-10.0) in the experimental group and 7.0 (5.0-9.0) in controls (p=0.026). There were no group differences in ratings of subjective pain or visual disturbances. Median microscope light intensity was lower in the experimental group than controls; 3425.0 (2296.0-4300.0) Lux vs 24 279.0 (16 000.0-26 500.0) Lux (p<0.0001), respectively.

CONCLUSION

Compared with conventional microscopes, the NGENUITY 3D visualisation system allows surgeons to operate with lower levels of light exposure, resulting in significantly less glare and improved comfort in patients undergoing cataract surgery.

TRIAL REGISTRATION NUMBER

NCT05085314.

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.

Comparison of novel digital microscope using integrated intraoperative OCT with Ngenuity 3D visualization system in phacoemulsification

OBJECTIVE

To compare surgical efficiency, visual and physical comfort, and safety profile of the ARTEVO 800 Digital Microscope (Carl Zeiss Meditec AG, Jena, Germany) and the Ngenuity 3D Visualization System (Alcon Laboratories Inc, Fort Worth, TX) in cataract surgery.

DESIGN

Cross-sectional study.

PARTICIPANTS

One hundred consecutive phacoemulsification cataract surgeries performed by five surgeons from June 1, 2020, to November 1, 2020.

METHODS

For each case, the surgeons answered a 2-section questionnaire (before and after intervention) to collect data on cataract severity or grade, surgical risk, chosen three-dimensional (3D) visualization system, surgical complications, and the visual or physical discomfort experienced during the procedure.

RESULTS

Each of the 5 surgeons performed 20 surgeries (N = 100) using either the ARTEVO 800 Digital Microscope (N = 50) or the Ngenuity Visualization System (N = 50). Mean duration of the surgical procedure was 17.07 ± 4.80 minutes, and none of the surgeons ever switched to the classical microscope. In addition, 40% of surgeries were considered at low risk, 30% at intermediate risk, and 30% at high risk. The Zoom, Focus, and XY commands were used 1-3 times, respectively, during 76 (p = 0.34), 73 (p = 0.49), and 76 (p = 0.64) interventions. Surgical uncertainty and operative fluency were similar using both systems (p = 0.53 and p = 0.19). We observed 14 intraoperative complications, 9 using Ngenuity and 5 using the ARTEVO 800. Surgeon's visual comfort (p = 0.79), colour or brightness perception (p = 0.82), and visual impairment (p = 0.62) during surgery were similar for both systems. Headache, backache, and other musculoskeletal problems were reported, respectively, after 14 (p = 0.79), 11 (p = 0.99), and 8 (p = 0.44) procedures.

CONCLUSION

Both the Ngenuity 3D Visualization System (Alcon Laboratories Inc) and the ARTEVO 800 Digital Microscope (Carl Zeiss Meditec AG) provided comparable operative speed and overall surgical comfort during cataract surgery.

Image sharpening algorithms improve clarity of surgical field during 3D heads-up surgery

BACKGROUND

Image-sharpening algorithms with color adjustments enable real-time processing of the surgical field with a delay of 4 msec for heads-up surgery using digital three-dimensional displays. The aim of this study was to investigate the usefulness of the algorithms with the Artevo 800^® digital microscope.

METHODS

Seven vitreoretinal surgeons evaluated the effects of image-sharpening processing on the clarity of the surgical field with the Artevo 800^® system that is used for cataract and vitreous surgeries. The scorings were made on a 10-point scale for anterior capsulotomy, phacoemulsification, cortex aspiration, core vitrectomy, and peeling of an epiretinal membrane or an internal limiting membrane. In addition, the images during the internal limiting membrane peeling were processed with or without color adjustments. We also evaluated the skewness (asymmetry in the distribution of the pixels) and kurtosis (sharpness in the distribution of the pixel) of the images to evaluate the contrast with each intensity of image-sharpening.

RESULTS

Our results showed that the mean visibility score increased significantly from 4.9 ± 0.5 at 0% (original image) to 6.6 ± 0.5 at 25% intensity of the image-sharpening algorithm (P < 0.01). The visibility scores of the internal limiting membrane increased significantly from 0% (6.8 ± 0.3, no color adjustments) to 50% after the color adjustments (7.4 ± 0.4, P = 0.012). The mean skewness decreased significantly from 0.83 ± 2.02 at 0% (original source) to 0.55 ± 1.36 at 25% intensity of the image-sharpening algorithm (P = 0.01). The mean kurtosis decreased significantly from 0.93 ± 2.14 at 0% (original image) to 0.60 ± 1.44 at 25% intensity of the image-sharpening algorithm (P = 0.02).

CONCLUSIONS

We conclude that the image-sharpening algorithms can improve the clarity of the surgical field during 3D heads-up surgery by decreasing the skewness and kurtosis.

TRIAL REGISTRATION

This was a prospective clinical study performed at a single academic institution, and the procedures used were approved by the Institutional Review Committee of the Kyorin University School of Medicine (reference number, 1904). The procedures also conformed to the tenets of the Declaration of Helsinki.

Surgery-related characteristics, efficacy, safety and surgical team satisfaction of three-dimensional heads-up system versus traditional microscopic equipment for various vitreoretinal diseases

PURPOSE

To compare the three-dimensional (3D) heads-up surgery with the traditional microscopic (TM) surgery for various vitreoretinal diseases.

METHODS

A medical record review of patients that underwent 3D heads-up or TM vitreoretinal surgeries was performed from May 2020 to October 2021 in this retrospective case-control study. Main outcome measures included surgery-related characteristics, efficacy, safety, and satisfaction feedback from the surgical team.

RESULTS

A total of 220 (47.6%) and 242 (52.4%) eyes were included in the 3D and TM groups, respectively. The 3D heads-up system significantly benefits delicate surgical steps, like the epiretinal membrane (ERM) peeling for ERM and internal limiting membrane peeling for idiopathic macular holes (P < 0.05). The 3D heads-up system could facilitate a significantly better visual outcome for pathologic myopic foveoschisis (P = 0.049), while no difference by TM surgery (P = 0.45). For the satisfaction feedback, the 3D heads-up system was rated significantly higher in most subscales and the overall score (P < 0.05). The surgeons' ratings on operating accuracy and the first assistants' rating on operating accuracy and operation cooperation were significantly higher in the TM group than in the 3D group (P < 0.05). Besides that, the 3D heads-up surgery was comparable with TM surgery in the surgery-related characteristics, choice of tamponades, postoperative VA, primary anatomic success, and perioperative complications (P > 0.05).

CONCLUSION

The efficacy and safety of the 3D heads-up surgery were generally comparable to the TM surgery. The 3D heads-up system could significantly benefit delicate surgical steps and achieve better surgical team satisfaction.

Effects of image-sharpening algorithm on surgical field visibility during 3D heads-up surgery for vitreoretinal diseases

We conducted clinical and experimental studies to investigate the effects of image-sharpening algorithms and color adjustments, which enabled real-time processing of live surgical images with a delay of 0.004 s. The images were processed with image-sharpening intensities of 0%, 12.5%, 25%, and 50% during cataract surgery, vitrectomy, peeling of epiretinal membrane, and peeling of internal limiting membrane (ILM) with the Ngenuity 3D visualization system. In addition, the images obtained with a yellow filter during the ILM peeling were processed with color adjustments. Five vitreoretinal surgeons scored the clarity of the images on a 10-point scale. The images of a 1951 United States Air Force grating target placed in no fluid (control), saline, and 0.1% and 1% milk solution were evaluated. The results showed that the mean visibility score increased significantly from 5.0 ± 0.6 at 0% to 6.4 ± 0.6 at 12.5%, 7.3 ± 0.7 at 25%, and 7.5 ± 0.9 at 50% (P < 0.001). The visibility scores during ILM peeling improved significantly with color adjustments (P = 0.005). In the experimental study, the contrast of the grating targets blurred by the 0.1% and 1% milk solution increased significantly by the image-sharpening procedure. We conclude that the image-sharpening algorithms and color adjustments improved the intraoperative visibility of 3D heads-up surgery.

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).

Cognitive workload, complications and visual outcomes of phacoemulsification cataract surgery: Three-dimensional versus conventional microscope

PURPOSE

To compare the surgical workload, complications, and visual outcomes using the three-dimensional visualization system with the conventional microscope in phacoemulsification cataract surgery.

DESIGN

Prospective, non-randomized, open-label interventional study.

METHODS

All patients underwent phacoemulsification cataract surgery using the three-dimensional visualization system or conventional microscope.

RESULTS

Of the 203 eyes, 80 underwent surgery with the three-dimensional system while 123 underwent with the conventional microscope. No difference was noted in the total surgical duration, complication rates, and visual outcomes between the two groups. However, capsulorhexis was significantly faster using the conventional microscope while posterior chamber intraocular lens insertion was quicker using the three-dimensional system. In terms of cognitive workload comparison, no difference was seen in the surgeons' heart rate, oxygen saturation levels, and surgery task load index total workload score and workload score for all six dimensions of the questionnaire, between the three-dimensional system and conventional microscope groups. As compared to baseline, the heart rate increased significantly during all surgical steps and at the end in both groups. When compared to baseline, the oxygen saturation levels were significantly raised during capsulorhexis, irrigation, and aspiration and posterior chamber intraocular lens insertion and at the end of the surgery in the three-dimensional group and during incision and at the end of the surgery in the conventional microscope group.

CONCLUSIONS

The duration of surgery, complications, and visual acuity outcomes remain unaffected while performing phacoemulsification cataract surgeries with the three-dimensional viewing system when compared to the conventional microscopes. Moreover, the surgeons' cognitive workload too remains unaffected while utilizing this revolutionary three-dimensional surgical technology.

Initial experience with three-dimensional heads-up display system for cataract surgery - A comparative study

Purpose:

To compare the complication rates, surgical time and learning curve using the 3-D Heads up display system in comparison with the conventional microscope for routine cataract surgery.

Methods:

Consecutive consenting adults with uncomplicated cataract were offered phacoemulsification using the 3-D Heads up display system (ARTEVO 800 Carl Zeiss Meditec) or the conventional microscope (Zeiss Lumera 700) by two experienced surgeons. Surgical time, measured from start of corneal incision to removal of microscope from the surgical field and complication rates were compared between the groups.

Results:

Of the 343 eyes enrolled, 100 (29%) underwent surgery using the 3-D Heads up display system. The surgical time for 3-D Heads up display system was significantly higher in the 3-D group (8.4 ± 2.1 vs. 6.5 ± 1.8 minutes, P < 0.001). There were no group differences in surgical complications (2% in 3-D vs. 2.5% in conventional microscope, P = 0.28). Comparing across 4 quartiles within the 3-D group, the mean surgical time was slightly higher during the 1^st quartile (n = 25, 9.1 ± 1.9 minutes) compared to the last quartile (n = 25, 8.2 ± 1.9 minutes) (p = 0.17). Complications in the 3-D group occurred only in the initial 50% of cases. Seven (7%) cases in the 3-D group were converted to conventional binocular microscope of which 3 each were due to difficulty in depth perception and low illumination while one was due to intraoperative pupillary constriction.

Conclusion:

Phacoemulsification with the 3-D Heads up display system takes longer time but offers excellent visualization, ergonomics and safety compared to conventional microscopes. Experienced surgeons should be able to adapt easily after their first 50 surgeries.