The clinical efficacy of preoperative flash visual evoked potential (VEP) for mature cataracts without a response to pattern VEP

BACKGROUND

This study aims to assess the effectiveness of the preoperative flash visual evoked potential (VEP) test in predicting postoperative visual acuity for monocular mature cataract cases when compared to the contralateral normal eye.

METHODS

The study included 60 patients, each with a monocular mature cataract diagnosis, who underwent preoperative flash VEP testing showing no pattern VEP response. Subsequently, phacoemulsification was performed. The relationship between the flash VEP test latency values (P1, N2, P2) and amplitude value (N2-P2), and the degree of visual acuity recovery 3 months post-cataract surgery, was evaluated using the LogMAR scale. Furthermore, a linear regression analysis was conducted to explore the connection between preoperative flash VEP components and postoperative visual acuity.

RESULTS

The average age of the patients was 65.4 ± 13.6 years, with a range of 43 to 87 years. The study included 36 males and 24 females. A significant disparity in visual acuity was observed between the preoperative and 3-month postoperative stages (p < 0.001). The preoperative flash VEP test for mature cataracts revealed significant delays in P1, N2, and P2 latency, as well as a reduction in N2-P2 amplitude potential when compared to the contralateral normal eye (p < 0.001). Notably, delayed P2 latency and reduced N2-P2 amplitude potential were particularly indicative of poor visual acuity prognosis after cataract surgery in the multiple regression analysis (p < 0.05). The N2-P2 amplitude potential was the important value that exhibited statistically significant results, with an area under the curve (AUC) of 80% sensitivity and 88% specificity, using a cutoff value of 6.07 μV.

CONCLUSIONS

In cases of monocular mature cataract, a reduction in N2-P2 amplitude potential compared to the contralateral normal eye emerged as the most reliable predictor of postoperative visual prognosis following cataract surgery.

Comparative Study of Safety Outcomes Following Nucleus Disassembly with and without the miLOOP Lens Fragmentation Device During Cataract Surgery

Purpose

To determine the effect of a microinterventional lens prefragmentation wire loop device (miLOOP®; Carl Zeiss Meditec AG, Oberkochen, Germany), on adverse events (AEs), cumulative dispersed energy (CDE), and vision outcomes when used before phacoemulsification of high-grade mature cataracts.

Setting

Three ambulatory surgical centers in the Peoria, IL region.

Design

Retrospective comparative consecutive case series; single-surgeon.

Methods

Patient outcomes were compared before and after introduction of miLOOP-assisted lens fragmentation prior to phacoemulsification during cataract surgeries performed 2016‒2020. The primary outcome was intraoperative AE rate/type. Secondary outcomes included ultrasound cumulative dispersed energy (CDE) administered during phacoemulsification, postoperative AEs, and best-corrected visual acuity (BCVA).

Results

Data from 765 subjects (mean age 72.9 years; 1025 eyes) comprised 524 conventional lens disassembly (Control) eyes and 501 Device eyes. One hundred percent of the cataracts in both groups were advanced WHO Grade 3+ nuclei. Significantly fewer intraoperative AEs occurred in the Device group versus Controls (2.2% and 6.3% of eyes, respectively; p=0.0011). Postoperative AE rates were comparable between groups (Controls=2.9%, Device=3.5%). Mean CDE from ultrasound was significantly reduced by 21% when the microfilament loop device was used for nuclear disassembly (9.6±5.2 CDE units) versus Controls (11.6±6.4 CDE units; p<0.0001). Median postoperative BCVA was 20/25 Snellen (0.091 logMAR) in both groups. More than 70% of both Control and Device eyes had postoperative BCVA better than 20/30 Snellen.

Conclusion

Microinterventional lens fragmentation was associated with lower ultrasound energy use and improved intraoperative safety than traditional unassisted surgery of advanced high-grade cataracts, while maintaining similarly acceptable postoperative complication rates and BCVA functional outcomes.

Trends in cataract surgical treatment within the Brazilian national public health system over a 20-year period: Implications for Universal Eye Health as a global public health goal

Cataract is a highly prevalent, treatable, and sight threatening condition considered one of the main focuses of public health policies addressing visual impairment and blindness towards Universal Eye Health. We aimed to investigate the trends on number of cataract surgical procedures performed through the Brazilian national health system (SUS) from 2000 to 2019 while also evaluating costs associated with it. The Brazilian Public Health System Information Database (DATASUS) was used as the primary data source for procedures including extracapsular cataract extraction (ECCE) and phacoemulsification. Trends along the years were evaluated through generalized linear models. A total of 8,424,521 cataract procedures were performed from 2000 to 2019, with a significant increase along the years from 228,145 in 2000 to 663,186 in 2019 (p<0.001), a cataract surgical procedure rate change from 13.15 to 32.28 procedures per 10,000 people. It was observed a significant increase on the number of phacoemulsification (p<0.001) and a significant decrease on the number of ECCE (p<0.001). A shift on the predominant technique has occurred between 2007 and 2008 with phacoemulsification increasing its percentual representativity from 34.3% to 69.7% of all procedures, reaching 96.1% in 2019. Phacoemulsification costs per procedure increased 30.5% from from USD$119.00 to USD$155.33 (p = 0.007) and the ECCE costs per procedure increased 29.1% from USD$78.57 to USD$101.43 (p = 0.001). There is an increasing trend of procedures related to cataract treatment performed through SUS along the 20-years period and a switch on the technique predominance from ECCE to phacoemulsification was observed after 2007. The costs associated with both techniques have increased but have not followed the country's overall inflation. Data derived from DATASUS is important to understand the overall panorama of ocular health offered by the national health system and to provide information to guide healthcare leaders on management and planning of public health policies within the system.

Population-Based Cataract Surgery Complications and Their Impact on Visual Status in the Brazilian Amazon Region

PURPOSE

To investigate cataract surgery prevalence, complications, visual outcomes, and coverage in a population of older adults from the Brazilian Amazon region.

DESIGN

Population-based cross-sectional study.

METHODS

Individuals ≥45 years of age from urban and rural areas of Parintins City, Brazil, were identified by cluster random sampling. Participants underwent ophthalmic examination, including uncorrected visual acuity, acuity with presenting correction (APC), and best-corrected visual acuity (BCVA) from each eye. In those with previous cataract surgery, surgical technique and complications including its contribution to vision impairment were noted. The association of surgical complications and surgical coverage with sociodemographic variables was assessed by multiple logistic regression.

RESULTS

A total of 2,384 persons were determined to be eligible, and 2,041 (85.6%) were examined. Overall, prevalence of cataract surgery was 8.6%, with 11.3% urban and 5.0% rural. Surgical complications were associated with males, older age, and urban residency and were found in 60.4%, with posterior capsule opacification in 29.6% and posterior capsule rupture in 16.3%. Among the 270 eyes having cataract surgery, APC ≥20/32 was found in 44.4%, APC 20/40 to 20/63 in 20.8%, APC <20/63 to 20/200 in 14.4%, APC <20/200 to 20/400 in 2.6%, and APC <20/400 in 17.8%. Low surgical coverage was found with 57.9% of those with visual impairment due to cataract not being treated surgically.

CONCLUSIONS

Although a reasonable prevalence of cataract surgery was found, a high complication rate, poor visual outcomes, and low cataract surgery coverage indicated that actions to improve quality and appropriate postsurgical management should be planned and implemented by public health authorities.