Macular edema after uncomplicated cataract surgery: a role for phacoemulsification energy and vitreoretinal interface status?

Virtual reality simulation and real-life training programs for cataract surgery: a scoping review of the literature

BACKGROUND

Cataract surgery requires a high level of dexterity and experience to avoid serious intra- and post-operative complications. Proper surgical training and evaluation during the learning phase are crucial to promote safety in the operating room (OR). This scoping review aims to report cataract surgery training efficacy for patient safety and trainee satisfaction in the OR when using virtual reality simulators (EyeSi [Haag-Streit, Heidelberg, Germany] or HelpMeSee [HelpMeSee foundation, Jersey city, New Jersey, United States]) or supervised surgical training on actual patients programs in residents.

METHODS

An online article search in the PubMed database was performed to identify studies proposing OR performance assessment after virtual-reality simulation (EyeSi or HelpMeSee) or supervised surgical training on actual patients programs. Outcome assessment was primarily based on patient safety (i.e., intra- and post- operative complications, OR performance, operating time) and secondarily based on trainee satisfaction (i.e., subjective assessment).

RESULTS

We reviewed 18 articles, involving 1515 participants. There were 13 using the EyeSi simulator, with 10 studies conducted in high-income countries (59%). One study used the HelpMeSee simulator and was conducted in India. The four remaining studies reported supervised surgical training on actual patients, mostly conducted in low- middle- income countries. Training programs greatly differed between studies and the level of certainty was considered low. Only four studies were randomized clinical trials. There were 17 studies (94%) proposing patient safety assessments, mainly through intraoperative complication reports (67%). Significant safety improvements were found in 80% of comparative virtual reality simulation studies. All three supervised surgery studies were observational and reported a high amount of cataract surgeries performed by trainees. However, intraoperative complication rates appeared to be higher than in virtual reality simulation studies. Trainee satisfaction was rarely assessed (17%) and did not correlate with training outcomes.

CONCLUSIONS

Patient safety assessment in the OR remains a major concern when evaluating the efficacy of a training program. Virtual reality simulation appears to lead to safer outcomes compared to that of supervised surgical training on actual patients alone, which encourages its use prior to performing real cases. However, actual training programs need to be more consistent, while maintaining a balance between financial, cultural, geographical, and accessibility factors.

Safety and Efficacy of Prostaglandin Analogues in the Immediate Postoperative Period after Uneventful Phacoemulsification

Prostaglandin analogues (PGAs) have been associated with the development of pseudophakic macular edema (PME) in complicated cataract cases, but evidence on their effects in uncomplicated phacoemulsification remains controversial. This two-arm, prospective, randomised study included patients with glaucoma or ocular hypertension under PGA monotherapy who were scheduled for cataract surgery. The first group continued PGA use (PGA-on), while the second discontinued PGAs for the first postoperative month and reinitiated use afterwards (PGA-off). Topical non-steroidal anti-inflammatory drugs (NSAIDs) were routinely administered to all patients during the first postoperative month. The patients were followed up for three months and the primary outcome was PME development. Secondary outcomes were corrected distance visual acuity (CDVA), central and average macular thickness (CMT and AMT), and intraocular pressure (IOP). The analysis included 22 eyes in the PGA-on group and 33 eyes in the PGA-off group. No patient developed PME. CDVA was not significantly different between the two groups (p = 0.83). CMT and AMT showed a small but statistically significant increase until the end of follow-up (p < 0.001). Mean IOP values had no significant differences between the groups at each visit (p > 0.05). At the end of follow-up, the IOP values were significantly lower than baseline in both groups (p < 0.001). In conclusion, PGA administration with concomitant topical NSAIDs appears to be a safe practice in the early postoperative period of uncomplicated phacoemulsification.

Technical failure rates for biometry between swept-source and older-generation optical coherence methods: a review and meta-analysis

PURPOSE

Precise ocular measurements are fundamental for achieving excellent target refraction following both cataract surgery and refractive lens exchange. Biometry devices with swept-source optical coherence tomography (SS-OCT) employ longer wavelengths (1055-1300 nm) in order to have better penetration through opaque lenses than those with partial coherence interferometry (PCI) or low-coherence optical reflectometry (LCOR) methods. However, to date a pooled analysis showing the technical failure rate (TFR) between the methods has not been published. The aim of this study was to compare the TFR in SS-OCT and in PCI/LCOR biometry.

METHODS

PubMed and Scopus were used to search the medical literature as of Feb 1, 2022. The following keywords were used in various combinations: optical biometry, partial coherence interferometry, low-coherence optical reflectometry, swept-source optical coherence tomography. Only clinical studies referring to patients undergoing routine cataract surgery, and employing at least two (PCI or LCOR vs. SS-OCT) optical methods for optical biometry in the same cohort of patients were included.

RESULTS

Fourteen studies were included in the final analysis, which presented results of 2,459 eyes of at least 1,853 patients. The overall TFR of all included studies was 5.47% (95% confidence interval [CI]: 3.66-8.08%; overall I² = 91.49%). The TFR was significantly different among the three methods (p < 0.001): 15.72% for PCI (95% CI: 10.73-22.46%; I² = 99.62%), 6.88% for LCOR (95% CI: 3.26-13.92%; I² = 86.44%), and 1.51% for SS-OCT (95% CI: 0.94-2.41%; I² = 24.64%). The pooled TFR for infrared methods (PCI and LCOR) was 11.12% (95% CI: 8.45-14.52%; I² = 78.28%), and was also significantly different to that of SS-OCT: 1.51% (95% CI: 0.94-2.41%; I² = 24.64%; p < 0.001).

CONCLUSIONS

A meta-analysis of the TFR of different biometry methods highlighted that SS-OCT biometry resulted in significantly decreased TFR compared to PCI/LCOR devices.

Changes in chorioretinal flow index after cataract surgery: an optical coherence tomography angiography study

PURPOSE

Pseudophakic cystoid macular edema (CME) occurs in up to 2% of uneventful cataract surgeries. This study evaluates changes in macular blood flow succeeding uneventful phacoemulsification cataract extraction among otherwise visually healthy subjects.

METHODS

This prospective study included 18 eyes of 18 patients undergoing routine phacoemulsification. Optical coherence tomography angiography (OCT-A) was performed using the Angio-Retina 6 × 6 mm protocol with the XR Avanti Angio-Vue system (Optovue Inc., Fremont, California) prior to the surgery and 4-8 weeks thereafter. Exclusion criteria included motion artifacts, segmentation errors and signal strength index (SSI) < 40. The main outcome measure was change in flow index (FI) measured in all 4 retinal segmentation layers within an area of 1 mm diameter around the foveal center.

RESULTS

Following surgery, a significant increase in SSI (46.65 ± 8.62 versus 53.12 ± 8.07, p = 0.01), superficial plexus FI (0.98 ± 0.23 versus 1.16 ± 0.16, p = 0.02) and deep plexus FI (0.54 ± 0.46 versus 0.93 ± 0.39, p = 0.01) was found. No significant changes were noted in the outer retina or the choriocapillaris.

CONCLUSION

The study demonstrates a significant increase in FI in the superficial and deep retinal plexus following uneventful cataract surgery, with the greatest changes occurring in the latter. These findings corroborate evidence from structural imaging and support the vascular etiology of pseudophakic CME.

Intravitreal fluocinolone acetonide implant for chronic postoperative cystoid macular edema - two years results

PURPOSE

We report visual and anatomical outcomes of chronic postoperative macular edema treated with a fluocinolone acetonide intravitreal implant.

METHOD

Retrospective study of chronic, post-surgical CME treated with a fluocinolone acetonide intravitreal implant. Best registered visual acuity (BRVA), central retinal thickness (CRT), and Goldmann tonometry intraocular pressure (IOP) were assessed over 24 months. The need for IOP lowering treatment, top-up therapy during follow-up, and complications were also assessed.

RESULTS

We analyzed 16 consecutive eyes of 16 patients with chronic, post-surgical CME treated with fluocinolone acetonide intravitreal implant. Surgical indications included cataract surgery, vitrectomy plus membrane peeling and combined phaco-vitrectomy. Baseline mean BRVA of 0.8 ± 0.65 logMAR improved to 0.60 ± 0.4 logMAR (p = 0.02) at 12 months and to 0.7 ± 0.5 logMAR (p = 0.32) at 24 months. At month 12, BRVA improved in 11 eyes, stabilized in 4 eyes, and decreased in 1 eye. At month 24, VA remained improved in 5 eyes, remained stabilized in 5 eyes, and decreased in 1 eye. Mean CRT decreased from 524 ± 132 μm at baseline to 389 μm at month 3, 347 μm at month 6, 355 ± 106 μm (p = 0.0003) at month 12, and 313 ± 83 μm (p = 0.0001) at month 24. At 12 months, CRT improved in 13 eyes and remained unchanged in 2 eyes. At 24 months, CRT improved further in 8 eyes, and stabilized in 3 eyes. Increased IOP (≥21 mmHg) was observed only in 4 eyes, all successfully managed with topical medication. No further side effects were observed in any patient.

CONCLUSION

Visual and anatomic improvements were achieved by a single fluocinolone acetonide implant with few side effects up to 24 months in CME eyes with a long and heavy prior treatment history.

An Assessment of Cataract Severity Based on Antioxidant Status and Ascorbic Acid Levels in Aqueous Humor

Cataract is the leading cause of blindness throughout the world. Currently, the cataract severity evaluation is based on the subjective LOCS III guideline. To ameliorate the evaluation system and develop an objective and quantitative analysis, we investigated the relationships among aqueous humor total antioxidant capacity (AqTAC), ascorbic acid (AqAA) concentration, and cataract severity. In this study, we enrolled 130 cataract patients who underwent phacoemulsification between April 2019 and March 2020. The AqTAC and AqAA were measured by our own developed TAC assay and commercially available kit. Cataract severity was recorded by nuclear opalescence (NO) and cortical cataract (CC) degree according to LOCS III. Cumulative dissipated energy (CDE) during phacoemulsification was recorded to verify the severity of the cataract. As a result, we found a moderate correlation between AqTAC and CDE (p < 0.001). In addition, we found AqTAC independently associated with the CDE when analyzed by multivariate linear regression (p < 0.001). AqTAC also negatively correlated to cataract severity when measured by NO and CC (p = 0.012 in NO grade 3 vs. grade 1; p = 0.012 in CC grade 2 vs. grade 1; p < 0.001 in CC grade 3 vs. grade 1). We further found AqAA provided 71.9 ± 13.5% of AqTAC, and showed a high correlation (rho = 0.79, p < 0.001). In conclusion, we found a significant correlation between AqTAC/AqAA and cataract severity measured by CDE. The correlation was superior to the correlation between LOCS III and CDE. Aqueous humor TAC owns the potential to assess cataracts in an objective and quantitative way.

Phase IV clinical study to evaluate the effects of an intracameral combined mydriatic and anesthetic agent and standard topical mydriatics and anesthetics on the ocular surface after cataract surgery

PURPOSE

To compare intracameral and topical mydriatics and anesthetics in cataract surgery.

SETTING

Institute of Ocular Microsurgery, Barcelona, Spain.

DESIGN

Phase IV, open-label, randomized, single-center study.

METHODS

Patients were randomized in a 1:1 ratio to receive intracameral mydriatic-anesthetic (Mydrane/Fydrane) and anesthetic eyedrops or control (topical eyedrops only). The other treatment was administered for the second cataract surgery. Assessments were performed at presurgery and immediately postsurgery, at 12 to 36 hours postsurgery (day 1), and 7 days postsurgery. The primary endpoint was the change from baseline in corneal/conjunctival surface staining. The secondary endpoints included assessments of epithelial alterations, point-spread function, ocular surface disease index, conjunctival hyperemia, vision breakup time, ocular symptoms/signs, adverse events (AEs), corrected distance visual acuity, intraocular pressure, patient/investigator satisfaction, and procedure time.

RESULTS

A total of 50 patients undergoing sequential cataract surgery in both eyes were included. Baseline assessments were similar in each group. The difference between Fydrane and control groups for the change from baseline at day 1 in corneal and conjunctival surface staining was not statistically significant. For Fydrane, postoperative epithelial alterations were fewer at day 1 (P < .005), folliculopapillary reaction was less frequent (P < .05), some ocular symptoms were less frequent and milder (P < .05), length of procedure was shorter (P < .001), and patient and investigator satisfaction were better (P < .05). There were few AEs in both groups.

CONCLUSIONS

Fydrane reduced ocular surface damage by decreasing corneal epithelial and conjunctival toxicity with faster recovery of surface integrity compared with topical eyedrops, improved patient and investigator satisfaction, and reduced procedure time.

PREOPERATIVE VITREORETINAL INTERFACE ABNORMALITIES ON SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY AS RISK FACTOR FOR PSEUDOPHAKIC CYSTOID MACULAR EDEMA AFTER PHACOEMULSIFICATION

PURPOSE

We assessed the role of vitreoretinal interface status in the development of pseudophakic cystoid macular edema (PCME) after cataract surgery.

METHODS

Prospective cohort study in which 112 patients (112 eyes) scheduled for cataract surgery were selected at random to undergo spectral domain optical coherence tomography (OCT) within 1 week preoperatively and at 1 and 3 months postoperatively. Spectral domain OCT macular images included no vitreoretinal contact, focal and diffuse vitreomacular adhesion, focal and diffuse vitreomacular traction, epiretinal membrane, macular hole, and macular edema.

RESULTS

The incidence of PCME was 11.6% (13 eyes), all of them being diagnosed at 1 month, and 7 eyes resolved at 3 months. The only risk factor for PCME was detection of nonsurgical epiretinal membrane by spectral domain OCT before phacoemulsification, being developed in 5 of 16 eyes (χ = 0.08, odds ratio 4.53, 95% confidence interval 1.28-16.13). Other variables such as posterior vitreous detachment, subfoveal choroidal thickness, diabetes, or hypertension were not significantly associated with PCME.

CONCLUSION

In this cohort, preoperative detection of epiretinal membrane by spectral domain OCT was a risk factor for PCME after cataract extraction. It is recommended to perform a spectral domain OCT before cataract surgery because the presence of an epiretinal membrane may be passed unnoticed by fundus examination.

Incidence of Irvine Gass Syndrome after Phacoemulsification with Spectral-Domain Optical Coherence Tomography

Purpose: Incidence of significant and non-significant macular edema found using spectral-domain optical coherence tomography (SD-OCT) following cataract surgery.Methods: Prospective, cohort series conducted at the Croix Rousse University Hospital. Significant macular edema (SME) was defined as the presence of fluid with an increase of 30% or more in central subfield macular thickness compared to baseline on SD-OCT at 6 weeks and non-significant macula edema (NSME) as an increase of less than 30%.Results: Nine hundred and twenty-eight eyes in 638 patients were included in the study. Incidence of Irvine Gass (IG) syndrome was 9%, 2.3% of patients presented SME, 6.8% NSME. Epiretinal membrane, diabetes, and capsular rupture were significantly associated with a risk of IG. The risk of developing IG in the fellow eye was 23% in cases of IG in the first eye. In total 8.4% of all included patients developed chronic IG (duration of more than 6 months).Conclusion: This study reports the incidence of IG during 6 months of surgical activity at a French university hospital center.

Evaluation of the efficacy and safety of a standardised intracameral combination of mydriatics and anaesthetics for cataract surgery

Background/aims

To compare the efficacy and safety of intracameral (IC) administration at the beginning of cataract surgery, of Mydrane, a standardised ophthalmic combination of tropicamide 0.02%, phenylephrine 0.31% and lidocaine 1%, to a standard topical regimen.

Methods

In this international phase III, prospective, randomised study, the selected eye of 555 patients undergoing phacoemulsification with intraocular lens (IOL) implantation received 200 μL of Mydrane (Mydrane group) just after the first incision or a topical regimen of one drop each of tropicamide 0.5% and phenylephrine 10% repeated three times (reference group). The primary efficacy variable was achievement of capsulorhexis without additional mydriatics. The non-inferiority of Mydrane to the topical regimen was tested. The main outcome measures were pupil size, patient perception of ocular discomfort and safety.

Results

Capsulorhexis without additional mydriatics was performed in 98.9% of patients and 94.7% in the Mydrane and reference groups, respectively. Both groups achieved adequate mydriasis (>7 mm) during capsulorhexis, phacoemulsification and IOL insertion. IOL insertion was classified as ‘routine’ in a statistically greater number of eyes in the Mydrane group compared with the reference group (p=0.047). Patients in the Mydrane group reported statistically greater comfort than the reference group before IOL insertion (p=0.034). Safety data were similar between groups.

Conclusions

Mydrane is an effective and safe alternative to standard eye drops for initiating and maintaining intraoperative mydriasis and analgesia. Patients who received IC Mydrane were significantly more comfortable before IOL insertion than the reference group. Surgeons found IOL insertion less technically challenging with IC Mydrane.

Trial registration number

NCT02101359; Results.