Application of different phacoemulsification and chopping techniques in hard nuclear cataract surgery / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To analyze the efficacy of bevel-up phaco chop versus bevel-down phaco drill in the treatment of hard nuclear cataract and the influence on corneal endothelium.<p>METHODS: Between August 2018 and April 2020, 94 patients(104 eyes)with hard(grade Ⅳ-Ⅴ)nuclear cataract treated with phacoemulsification were enrolled in this retrospective study. Among them, 50 eyes treated by bevel-up phaco chop were included in the control group, while 54 eyes treated by phaco drill technique were included in the observation group. The time of using ultrasound, ultrasonic energy and accumulated energy complex parameter in the two groups were recorded. The best corrected visual acuity(BCVA)in 7d, corneal endothelial cell count in 2mo, the proportions of normal hexagonal cells and the degree of corneal edema in 7d were compared between the two groups.<p>RESULTS: The time of using ultrasound, ultrasonic energy and accumulated energy complex parameter of the observation group were shorter and lower than those of the control group(<i>P</i><0.05). The BCVA of both groups increased after operation, and the observation group had higher BCVA than the control group at the same time(<i>P</i><0.05). In 1 and 2mo, the corneal endothelial cell counts and the proportions of normal hexagonal cells in both groups were lower than those before operation. Meanwhile, the corneal endothelial cell count and the proportions of normal hexagonal cells in the observation group were higher than those in the control group(<i>P</i><0.05). Besides, corneal edema was milder in the observation group than in the control group at 24h and 7d after operation(<i>P</i><0.05).<p>CONCLUSION: Compared with bevel-up phaco chop, phaco drill can significantly shorten the time of using ultrasound, reduce ultrasound energy, promote visual recovery, and reduce corneal endothelial cell damage.

Short-term Change of Corneal Endothelium after Phacoemulsificatin using Phaco-drill Technique

Phaco-drill technuque, is a method of phacoemulsifying cataractous lens with a bevel down position of phacotip, thus concentrating vacuum and ultrasonic power on center of the lens. This enables the phacoemulsification to be completed with a lower setting of energy. In this study, we evaluated the efficacy of the phaco-drill technique by measuring corneal endothelial cell damage. Since August 1997, we examined 170 patients who had under-gone phacoemulsification using phaco-drill technique, for uncorrected visual acuity, number, shape and size of corneal endothelial cell, and corneal thickness before and 2 months after surgery. the mean visual acuity was 0.26+/-0.24 before operation,and the mean visual acuity at 1 day and 2 months postlperatively was 0.59+/-0.32 and 0.82+/-0.26, respectively. The mean time of phacoemulsification was 58+/-41 seconds, and the average power(surgeon mode)was 8.6+/-0.26%. Mean volume of irrigating solution used in the operation was 116.12+/-52.10cc and that of aspirated solution was 63.34+/-30.37cc. The number of endothelial cells decreased from 2450+/-308.6 cell/mm2 before operation to 2234+/-372.2 cell/mm2 2 months after operation(9.2% decrease). The size of endothelial cells increased from 33.78+/-5.53/micrometer(2) before operation to 34.70+/-5.79/micrometer(2) 2 months after the operation(2.7% increase). The regularity of the cells (hexagonality) showed a decrease of 3%, from 57.47+/-10.16 before operation to 55.81+/-10.49% 2 months after the operation. The corneal thickness increased from 528+/- 36micrometer before operation to 590+/-8micrometer 1 dat(11.7% increase) and 531+/-4micrometer(0.5% increase) after the operation. From the results of this study we suggested that phaco-drill technique might be one of effective methods of phacoemulsification for less damage of corneal endothelial cells and less fluid consumption.

Phacoemulsification by Phaco-Drill Method with Microseal Phaco Tip

Phacoemulsification has been regarded as a preferable extracapsular cataract extraction due to rapid improvement of vicual acuity and small amount of surgically induced astigmatism. Since its introduction in 1967 by Kelman, the technique of phacoemulsification has been developed from sculpting method to divide and conquer and chopping methods by several cataract surgeons. The efficacy of phaco-drill techniquer with Microseal type phaco tip, developed by C-K Joo was evaluated in this study. 563 eyes were operated on by Joo from April, 1995 to April, 1996. The cataractous lenses were divided into NO2Inuclear opacity), NO3, NO4, and NO5 according to the Lens Opacification Classification System(LOCS) III and the number of each were 140, 207, 125 and 91, respectively. Rapid impr- ovement of uncorrected visual acuity was noted at postoperative on day; 0.5-0.6 in NO2, 0.4-0.5 in NO3, and 0.3-0.4 in NO4 and NO5. The average consumption of irrigating solution during the operations was under 100ml in most cases. The average real action(%, sec) of phacoemulsifications calculated as power x time was increased from 538 in NO2 to 3747 in NO5 depending on the severity of lens opacity. Combination of phaco-drill and chopping technique was used in 67 cases of NO5. Posterior capsule rupture occurred in 15 cases(2.66%). In this study we confirmed that phaco-drill technique with the phaco tip beveled down is a safe and efficient phacoemulsifying technique and be combined with the chopping technique.