Corneal endothelial damage in phacoemulsification using an anterior chamber maintainer compared with using an ophthalmic viscosurgical device

Examination of Vitreolenticular Interface in Relation to Different Phacoemulsification Parameters in Early and Late Postoperative Period

Background: The surgical parameters of phacoemulsification can significantly impact the behavior of the anterior hyaloid membrane (AHM). Methods: In this prospective study, anterior segment optical coherence tomography was used to examine the attachment or detachment of the AHM of 82 eyes after uneventful phacoemulsification preoperatively and postoperatively over 1 year. The impacts of the capsulorhexis' size, number of hydrodissections, nuclear sclerosis grade, cumulative dissipated energy (CDE), ultrasonic time, total surgical time, weakness of zonular fibers, presence of lens materials in Berger's space (LM-BS), and fluid usage were investigated in relation to the behavior of the AHM. Results: A significant linear trend regarding anterior vitreous detachment (AVD) was observed in the presence of zonular weakness and high CDE at all postoperative times (p ≤ 0.024 and p ≤ 0.005, respectively). Similarly, AVD was observed at 1-month, 3-month, and 1-year follow-ups in cases of high nuclear sclerosis grades (p ≤ 0.044) and high fluid usage (p ≤ 0.021). A significant correlation was observed in the group of LM-BS as the zonular weakness value increased (OR: 0.085; 95% CI: 0.017 to 0.420; p = 0.002), and the fluid usage was also significantly higher (OR: 1.049; 95% CI: 1.003-1.096; p = 0.037). Conclusions: Zonular weakness, high CDE, a hard nucleus, and high fluid usage are risk factors for postoperative AVD.

Cumulative Dissipated Energy (CDE) in Three Phaco-Fragmentation Techniques for Dense Cataract Removal

Purpose

To determine the energy expenditure in phacoemulsification surgery expressed as cumulative dissipated energy (CDE) among the divide and conquer, ultrachopper-assisted divide and conquer, and phaco-chop techniques for dense cataract removal.

Patients and Methods

The clinical data were obtained from the medical charts of dense cataracts patients undergoing routine phacoemulsification employing any of three phaco-fragmentation techniques, including divide and conquer using the Kelman 0.9 mm tip, the ultrachopper tip, and the phaco-chop technique using the Kelman 0.9 mm tip. Cumulated dissipated energy (CDE), longitudinal ultrasound time (UST), and endothelial cell loss were compared among groups at the one-month postoperative.

Results

Surgeries from 90 eyes were analyzed, among whom the conventional divide-and-conquer technique group included 30 patients, 32 in the ultrachopper group, and 28 in the phaco-chop technique group. The average CDE in the conventional divide and conquer group was 44.52 ± 23.00, the ultrachopper technique was 43.27 ± 23.18, and 20.11 ± 11.06 in the phaco-chop group. Phaco-fragmentation chop demonstrated significantly lower CDE than the other techniques (p= <0.0001). The phaco-chop technique showed statistically significantly lower CDE when compared to the other two groups (p=<0.0001) with 93.96 ± 39.71 seconds. There were no statistically significant differences in postoperative endothelial cell density between groups (p=0.4916).

Conclusion

The use of the phaco-chop technique in hard cataract phacoemulsification represents a lower energy expenditure than divide and conquer and ultrachopper techniques; nevertheless, no differences regarding endothelial density loss were evidenced.

Comparative evaluation of the results of phacoemulsification using domestic and foreign viscoelastics

BACKGROUND: Phacoemulsification, being the safest technique, is the golden standard of cataract surgery worldwide. However, as any surgery, it is accompanied by inevitable damage to intraocular structures. The most prevalent among them is the loss of corneal endothelial cells. In order to prevent these complications, various viscoelastics with particular features and characteristics are widely used. AIM: To compare the anatomical and functional state of ocular structures after standard phacoemulsification with monofocal posterior chamber intraocular lens (IOL) implantation using domestic (Kogevisc and Adgevisc) and foreign (Viscoat and Amvisc Plus) viscoelastics. MATERIALS AND METHODS: 60 cataract patients (60 eyes) were included in the clinical study, which were divided into two equal groups. In the first group (30 patients, 30 eyes), Adgevisc and Kogevisc (Solofarm, Russia) were used during the procedure. The mean age of the patients was 66 11 years. In the second group (30 patients, 30 eyes), Viscoat (Alcon) and Amvisc Plus (BauschLomb) were used. The mean age of the patients was 69.03 10.44 years. All patients underwent phacoemulsification with the implantation of the AcrySof IOL (model SA60AT, Alcon) according to the standard technique. Visual acuity, IOP level, CCT, corneal endothelial cell density were assessed. All studies were performed before surgery, the next day, 7 days and 1 month after surgery. RESULTS: In patients of the second group, on the 1st (p 0.05) and 7th day (p 0.01) after surgery, a statistically significant increase in IOP was revealed compared to the first group. The central cornea thickness in the early postoperative period was higher in patients of the second group, however, it was not statistically significant. The loss of corneal endothelial cells 1 month after surgery was 8.5 7.0% (p 0.01) in the first group and 6.6 6.4% in the second group (p 0.01). The mean value of endothelial cell loss in patients of the first group was higher, however, it was not statistically significant. The best corrected visual acuity in both groups at all stages of follow-up after surgery (days 1, 7 and 30) was comparable, there was no significant difference between the groups. CONCLUSIONS: The clinical efficacy of domestic adhesive and cohesive viscoelastics Adgevisc and Kogevisc (Solofarm, Russia) in phacoemulsification using the soft-shell technique is comparable to the foreign analogues Viscoat (Alcon) and Amvisc Plus (Bausch Lomb), which is confirmed by the absence of statistically significant differences in the studied parameters of the postoperative state of ocular structures and explained by their similar composition, molecular weight and viscosity.

Effect of Anterior Chamber Instability during Phacoemulsification Combined with Intraocular Lens Implantation

Purpose

To determine the incidence of anterior chamber (AC) instability during phacoemulsification (phaco) combined with intraocular lens implantation and investigate its effect on intraocular tissues.

Methods

Among the 248 enrolled eyes, 121 and 127 eyes were categorized into the irrigation and nonirrigation groups, respectively, depending on the use of a self-made anterior chamber maintainer (ACM) during phaco. AC stability was evaluated using operating microscopy and intraoperative optical coherence tomography (iOCT). Slit-lamp examination of AC flare and cells was performed 1 day postoperatively. Corrected distance visual acuity (CDVA), intraocular pressure (IOP), endothelial cell density (ECD), central corneal thickness (CCT), posterior vitreous detachment (PVD), and central foveal thickness (CFT) were evaluated preoperatively and at 1 week, 1 month, and 3 months postoperatively.

Results

There was good consistency in AC stability evaluation between operating microscopy and iOCT. The incidence of AC instability was significantly different between groups after the phaco and irrigation/aspiration tips were withdrawn from the AC (P < 0.001). At 1 day postoperatively, after excluding eyes in which the AC could not be visualized, AC cell grades were significantly lower in the irrigation group (P = 0.014). There was no significant difference in CDVA, IOP, ECD, and CCT between groups during the 3-month follow-up (P > 0.05). At 1 month and 3 months postoperatively, PVD occurred in 8 (16.3%) and 14 (28.6%) eyes and in 22 (40.7%) and 37 (68.5%) eyes in the irrigation and nonirrigation groups, respectively (P = 0.006 and P < 0.001). CFT was significantly higher in the nonirrigation group at 1 and 3 months postoperatively (P = 0.018 and P = 0.010).

Conclusions

Both operating microscopy and iOCT are efficient for AC stability evaluation. When the phaco and I/A tips were withdrawn from the AC, there was frequent instability. Intraoperative AC instability can increase surgery-induced inflammation and lead to postoperative complications such as PVD, retinal detachment, and macular edema. The self-made ACM can effectively reduce the incidence of intraoperative AC instability and these complications.