Phaco-chop Technique Research Articles

Evaluation of direct chop and stop-and-chop phacoemulsification techniques in moderate-grade cataract patients

Abstract AIMS: To compare direct chop and stop-and-chop phacoemulsification techniques in grade 3 and grade 4 cataract patients. DESIGN: A prospective randomized trial done for 1 year conducted in a tertiary care hospital on 100 eyes of 100 patients. MATERIALS AND METHODS: After taking informed consent, patients with nuclear cataract grade 3 and grade 4 according to Lens Opacities Classification System III without any coexisting corneal pathology, glaucoma, and traumatic cataracts were enrolled in the study. They were randomly grouped into group 1 (n = 50) patients undergoing phacoemulsification by direct chop technique and group 2 (n = 50) patients undergoing phacoemulsification by stop-and-chop technique. They were compared on parameters of endothelial cell count, central corneal thickness (CCT), and best corrected visual acuity (VA; BCVA) they were followed up on postoperative days 1, 7, 14, and 28. STATISTICAL ANALYSIS: Data are described in terms of mean and standard deviation, frequencies (number of cases), and relative frequencies (percentages) as appropriate. All analyses are completed using MS Excel. RESULT: The endothelial cell loss average at the end of 4 weeks postoperatively was higher in group 2 than in group 1 and this was statistically significant. The average CCT did not change between the two groups. The best corrected VA between the two groups was the same. CONCLUSIONS: The phaco chop techniques have evolved to have better endothelial cell counts postoperatively and minimize the use of ultrasound energy. This study over 1 year concludes that the direct chop technique of nucleotomy had better endothelial cell count postoperatively than the stop-and-chop method of nucleotomy. There is no statistically significant difference in CCT in both techniques.

Comparison between two-hole-assisted phaco-chop and stop-and-chop techniques for nuclear disassembly in residents’ cataract surgery

Abstract PURPOSE: The purpose of this study was to evaluate the safety of the novel two-hole-assisted phaco-chop technique as a transition between stop-and-chop and direct-chop techniques and to compare its phacoemulsification parameters with the stop-and-chop technique. METHODS: A prospective quasi-experimental study was conducted at Al-Shifa Trust Eye Hospital, Rawalpindi, Pakistan. One hundred and three patients (103 eyes), aged 18 years and above, with nuclear sclerosis (NS)+2, NS +3, +4, cortical, and posterior subcapsular cataracts (WHO Cataract Grading Group) were included, whereas patients with uveitis, glaucoma, traumatic cataracts, small pupils, zonular weakness, lens subluxation, small palpebral fissures, soft cataracts (NS + 1), and posterior polar cataracts were excluded from the study. The stop-and-chop technique was performed in 58 (56.3%) patients, whereas the two-hole-assisted chop technique in the rest. Ultrasound time (UST), total surgical time, and volume of balanced salt solution (BSS) delivered were recorded. RESULTS: The mean age of the participants was 65.12 ± 8.85 years. The comparison of the two techniques revealed no statistically significant difference in the UST (P = 0.723), volume of BSS used (P = 0.102), and total surgery time (P = 0.517). However, a significant positive correlation between cataract grade and UST (Spearman’s r = 0.888, P < 0.001), BSS volume delivered (Spearman’s r = 0.831, P < 0.001), and surgery time (Spearman’s r = 0.846, P < 0.001) was observed. Moreover, the UST comparison between cataract grades revealed a significant difference between the three groups (F = 185.09 P < 0.001). P < 0.05 was considered statistically significant. CONCLUSION: The two-hole-assisted phaco chop is a safe and efficient transitional technique between stop-and-chop and direct-chop techniques for nuclear disassembly in cataract surgery performed by resident surgeons. In addition, the phacoemulsification parameters of the two-hole-assisted chop technique are comparable with the stop-and-chop technique.

Phaco-Chop versus Divide-and-Conquer in Patients Who Underwent Cataract Surgery: A Systematic Review and Meta-Analysis.

Cataract surgery is one of the most frequently performed eye surgeries worldwide, and among several techniques, phacoemulsification has become the standard of care due to its safety and efficiency. We evaluated the advantages and disadvantages of two phacoemulsification techniques: phaco-chop and divide-and-conquer. PubMed, Cochrane, Embase, and Web of Science databases were queried for randomized controlled trial (RCT), prospective and retrospective studies that compared the phaco-chop technique over the divide-and-conquer technique and reported the outcomes of (1) Endothelial cell count change (ECC); (2) Ultrasound time (UST); (3) Cumulated dissipated energy (CDE); (4) Surgery time; and (5) Phacoemulsification time (PT). Heterogeneity was examined with I2 statistics. A random-effects model was used for outcomes with high heterogeneity. Nine final studies, (6 prospective RCTs and 3 observational), comprising 837 patients undergoing phacoemulsification. 435 (51.9%) underwent the phaco-chop technique, and 405 (48.1%) underwent divide-and-conquer. Overall, the phaco-chop technique was associated with several advantages: a significant difference in ECC change postoperatively (Mean Difference [MD] -221.67 Cell/mm2; 95% Confidence Interval [CI] -401.68 to -41.66; p < 0.02; I2=73%); a shorter UST (MD -51.16 sec; 95% CI -99.4 to -2.79; p = 0.04; I2=98%); reduced CDE (MD -8.68 units; 95% CI -12.76 to -4.60; p < 0.01; I2=84%); a lower PT (MD -55.09 sec; 95% CI -99.29 to -12.90; p = 0.01; I2=100). There were no significant differences in surgery time (MD -3.86 min; 95% CI -9.55 to 1.83; p = 0.18; I2=99%). The phaco-chop technique proved to cause fewer hazards to the corneal endothelium, with less delivered intraocular ultrasound energy when compared to the divide-and-conquer technique.

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

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. 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. 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). 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.

Chop and tumble nucleotomy - A technique for safe nuclear emulsification in posterior polar cataract.

A modified phaco chop technique for nuclear emulsification in posterior polar cataracts with nuclear sclerosis that avoids hydrodissection or nuclear rotation has been described. After performing a vertical chop maneuver to divide the nucleus, two pie-shaped nuclear fragments are removed from either side of the initial chop. The remaining nuclear fragments are then sequentially tumbled toward the center using the second instrument and emulsified while maintaining an intact epinuclear shell, which safeguards the fragile posterior capsule. The technique was successfully performed in 62 eyes of 54 patients with posterior polar cataract and grade II-IV nuclear sclerosis. The Chop and Tumble nucleotomy is a safe and effective technique for phacoemulsification in posterior polar cataracts with nuclear sclerosis, where hydrodissection and nuclear rotation are typically avoided.

The Stop and Press Technique; an Occlusion Free Stop-and-Chop Technique in Cataract Patients with Soft to Moderate Nuclei.

The stop-and-chop technique, which involves occlusion and chopping using vacuum to stabilize the nucleus, is an excellent combination of the divide-and-conquer and phaco-chop techniques. However, effectively chopping an un-solid (soft to moderate) nucleus is not easy, since the optimal vacuum to hold an un-solid nucleus is often associated with breaking of occlusion and aspiration of the nucleus. We modified the stop-and-chop technique such that occlusion and tight nucleus holding using ultrasound (US) power is not necessary. After completing the central groove and cracking the nucleus into two hemi-sections, the right nucleus half is chopped without nucleus rotation and occlusion. The right hemi-nucleus is stabilized by pressing against the right sac with the US tip without occlusion. Since this technique can reduce the risk of nucleus perforation and posterior capsular rupture, the surgeons can place the US tip firmly in a deep position, which provide safe and efficient nucleus division.

Eye-Related Factors That Can Be Associated With the Plane of Phacoemulsification.

Purpose: To evaluate the effect of eye-related factors such as biometric and surgical parameters, nuclear sclerosis (NS) grade, and pupil and capsulorhexis diameters on the plane of phacoemulsification (PP).Material and Methods: This prospective study included 328 eyes of 328 patients who underwent phacoemulsification surgery. The phaco-chop technique was performed in all patients and changes in PP that occurred during surgery were recorded. Patients were grouped as follows: Group 1, > 75% of lens nucleus emulsified in the capsular bag; Group 2, > 75% of lens nucleus emulsified at the pupillary plane; and Group 3, > 50% of lens nucleus emulsified in the anterior chamber. The association between PP and eye-related factors was evaluated.Results: There were 153 patients (46.7 %) in Group 1, 104 patients (31.7 %) in Group 2 and 71 patients (21.6 %) in Group 3. The factors associated with PP were anterior chamber depth (ACD) (p = 0.020) and NS grade (p = 0.028). No significant relationship was detected between PP and age, surgical parameters or other biometric values. Moreover, PP was found to be more anterior in patients with soft cataracts and deeper ACD values (p values were 0.002 and 0.036, respectively).Conclusion: The present study has reported that PP may move to more anterior, as softer cataracts may increase the fear of posterior capsule rent. Moreover, PP may move to more posterior due to shallow anterior chambers or high-grade cataracts that could potentially increase the fear of endothelial injury.

Application of prechop technique in phacoemulsification for cataract patients with highly liquefied vitreous: a retrospective study

BackgroundPhacoemulsification using phaco-chop technique has many challenging features in cataract patients with highly liquefied vitreous. This study aimed to compare the intraoperative parameters and safety between prechop technique and traditional phaco-chop in phacoemulsification for these patients.MethodsA total of 54 eyes of 54 patients with high myopia-related or post-vitrectomy cataract that underwent phacoemulsification combined with intraocular lens implantation were included in this retrospective study. Of them, 25 eyes that received manual prechop were included in the prechop group, and 29 eyes with best match of age, axial length and nuclear opalescence (NO) that received standardized phaco-chop were included as the control group. The intraoperative complications and surgery parameters were compared between groups.ResultsNo surgical complications were observed in the prechop group, while 2 eyes with posterior capsular rupture and 1 eye with a broken ciliary zonule (10.3%) were found in the control group. There was no significant difference in phaco time, average energy, and cumulative dissipated energy (CDE) between groups (all P > 0.05), but for hard nuclear cataracts with NO grading ≥ 5, prechop group required less phaco time (P = 0.008) and CDE (P = 0.029). There were significant correlations between phaco time vs. NO (r = 0.762 vs. 0.581, both P < 0.005) and CDE vs. NO (r = 0.717 vs. 0.668, both P < 0.001) in the prechop group and control group, respectively.ConclusionsThe prechop technique which seemed to have less intraoperative complications, reduced phaco time and CDE compared to standardized phaco-chop might be a good alternative for cataract patients with highly liquefied or vitrectomized vitreous, especially those with hard nuclear cataracts.

Comparison of corneal endothelial changes following phacoemulsification in diabetic and non-diabetic patients.

Purpose:To study corneal endothelial changes post phacoemulsification in diabetic and non-diabetic patients.Methods:A comparative, prospective, observational study was conducted on 100 diabetic and 100 non-diabetics who underwent phacoemulsification. All patients were operated by the same surgeon by using the phaco chop technique to exclude any surgeon-related bias. Endothelial cell count, CCT, and coefficient of variance (CV) were measured with a specular microscope along with BCVA preoperatively and at 1 week, 4 weeks, and 3 months postoperatively. For statistical analysis, data were analyzed by using SPSS (version 27.0; SPSS Inc., Chicago, IL, USA). Data were summarized as mean and standard deviation for numerical variables and count and percentages for categorical variables. Chi square test, independent sample T test, and paired T test were used to compare the data. P ≤ 0.05 was considered statistically significant.Results:Postoperatively at 1 week, 4-week, and 3 months follow-up intervals, the mean endothelial cell count and coefficient of variance were significantly higher, and the mean percentage of hexagonal cells was significantly lower in non diabetic as compared to the diabetic group. A significant difference in mean central corneal thickness of the two groups was observed at 1-week and 4-weeks postoperative intervals; at both these intervals, the mean value was significantly higher in non diabetic as compared to the non-diabetic group. However, at 3-months post-operative interval, the difference between the two groups was not significant statistically. Mean BCVA values were significantly higher in diabetic as compared to the diabetic group at all three follow-up intervals.Conclusion:The findings of the present study show that endothelial cell characteristics are adversely affected in diabetic eyes as compared to non-diabetic patients undergoing phacoemulsification; this might also have an effect on the visual outcomes.

A Counter Prechop Technique Using a Modified Universal Prechopper in Combination with or without Using a Universal Chopper.

PurposeTo introduce an alternative prechop technique without or with the use of a modified universal chopper (AE-2591, HI Kim chopper, ASICO, Inc. USA).MethodsPatients who underwent cataract surgery using the phaco-chop technique and the modified prechop technique have been grouped and reviewed retrospectively. Endothelial cell count (ECC) and central corneal thickness (CCT) measured 7 days pre-operatively, and 1 month and 3 months post-operatively, were compared between the two groups. In modified prechop technique, a narrow 1.7 mm neck prechopper (AE-4298, HI Kim-Inamura chopper, ASICO, Inc., USA) was used with universal chopper (AE-2591, HI Kim chopper, ASICO, Inc., USA) as an additional device for grade 4 and above cataracts or without it for grade 2 to 3 cataracts. Details of the surgical technique is further described in the Method section.ResultsA total of 104 eyes in the modified prechop group and 97 eyes in the phaco-chop group were enrolled in the study. Pre-operative nuclear opacity, ECC, and CCT as well as post-operative ECC (absolute value and the loss) and CCT (absolute value and the change) throughout the follow-up between the two groups did not show statistically significant differences.ConclusionCounter prechop technique using the modified prechopper and universal chopper is a safe, easy, and versatile surgical technique that can be applied broadly in a wide range of cases with various complexities, including LOCS lll N1 to N6 nuclei, hypermature cataracts, small pupils, and fragile suspensory zonular ligaments, with post-operative result not inferior to that of the conventional technique.

A comparative study of divide and conquer, stop and chop and phaco chop techniques of nucleotomy in phacoemulsification

Phacoemulsification is a variant of extracapsular cataract extraction surgery which is the gold standard treatment modality for cataract surgery nowadays. The common nucleotomy techniques of phacoemulsification are divide and conquer, stop and chop and phaco chop.Aim of this studyto compare different techniques of nucleotomy during phacoemulsification with respect to corneal endothelial cell loss, central corneal thickness (CCT) and comment on their merits and demerits. 60 patients undergoing cataract surgery by phacoemulsification were randomly divided into three groups of 20 each (Group A, B and C) who underwent nucleotomy by divide and conquer, stop and chop and phaco chop technique respectively. The preoperative endothelial cell density and central corneal thickness were recorded using Topcon SP3000P non-contrast specular microscope. All patients were followed up at 1, 4 and 12week after surgery and evaluated for vision, slit lamp examination, endothelial cell count and central corneal thickness.The age group of patients studied was 50-80 years, where maximum number of patients were in 51-60 years age group. Out of 60 patients, most common morphological type of cataract was nuclear (40%) cataract followed by cortico-nuclear (36.67%) cataract. After 1 week of surgery, drop in endothelial cell density was 7.06% in Group A, 6.49% in Group B and 6.84% in Group C patients. A further slight decrease in endothelial cell count was recorded during 4week and on final follow up visit at 12 weeks after cataract surgery, there was an endothelial cell loss of 9.51%, 10.9% and 11% in Group A, B and C respectively. The central corneal thickness at 1postoperative week increased by 2.75%, 2.35% and 2.20% in group A, B and C respectively. Further evaluation of CCT at 4and 12 week after surgery showed the values to be almost same as preoperative values. The rate of complications, which mainly included postoperative keratitis, mild anterior uveitis and cystoid macular edema, were found to be almost the same in all the three study groups.All the three nucleotomy techniques of phacoemulsification i.e divide and conquer, stop and chop and phaco chop are equally efficacious in terms of CCT changes, endothelial cell loss and complications rate in the hands of an experienced surgeon.

Two-hole assisted phaco-chop technique: a more efficient method for safe nucleofractis vertical chopping

PurposeTo evaluate the use of the two-hole technique in augmenting the efficiency of surgeons-in-training when performing the phaco-chop technique. We hypothesized that drilling two holes in opposite angles to each other adjacent to the capsulorhexis would mimic a new lens equator. The phaco-tip and the chopper can be inserted into these holes at appropriate depths and may sandwich and fracture the lens more easily than conventional methods.Methods The two-hole technique described above was performed by three first-year surgeons before they performed the standard phaco-chop technique. We collected data of their first 8 cases and analyzed a total of 64 cases: 16, divide-and-conquer; 24, two-hole method; 24, phaco-chop. The main outcome measures included the cumulative dissipated energy (CDE) and case ultrasound time (UST) with different phacoemulsification techniques.Results The young practicing surgeons eventually performed the standard phaco-chop more safely after repeated practice using the two-hole method. The drilling of holes enabled deep and effortless impaling of the nucleus. Although there was no significant difference in the CDE among the techniques, there was a significant difference in the UST (P < 0.05). ConclusionThe two-hole method enabled surgeons-in-training to acquire standard phaco-chop skills more efficiently. However, further studies with higher statistical power will be needed to validate these findings. Additionally, a variation of this technique, the four-hole method, is applicable even for experienced surgeons in cases of a hardened nucleus.

Phaco chop versus stop and chop nucleotomy techniques: A comparative evaluation

To perform a comparative evaluation of phaco chop versus stop and chop nucleotomy techniques in phacoemulsification. Materials and Methods: 60 patients with uncomplicated senile cataract were included in this study which were randomly divided into phaco chop group (group 1) and stop and chop group. (group 2) with 30 patients each and each group had 10 patients each of nuclear sclerosis grade II, III and IV. The main parameters were effective phaco time, total balanced salt solution used, total phacoemulsification power, intraoperative complications and postoperative visual acuity on day 1, 1st week and 3rd week. Results: The mean effective phacoemulsification time was 30.33±3.77 seconds in group 1 and 31.63 ± 4.22 seconds in group 2. The mean total phacoemulsification power in group 1 was 38.97 ± 4.33% whereas 41.93 ± 7.09 % in group 2. The mean total BSSV used in group 1 was 111.67 ± 13.86 ml whereas 113.17 ± 19.94 ml in group 2. The difference between the two groups was not significant. All patients received BCVA of 6/6 in both the groups after 3 weeks. Conclusion: The stop and chop technique and phaco chop technique are equally efficacious for nuclear cracking in patients in terms of visual acuity but if we compare according to nuclear grading, stop and chop technique requires more phaco power, phaco time and balanced salt solution which can lead to higher endothelial cell loss in grade IV nuclear cataract. Keywords: Cataract, Nucleotomy, Phacoemulsification, Phaco chop, Stop and Chop.

Evaluation of corneal endothelial cell changes in diabetic patients before and after phacoemulsification surgery: A comparative study

Aim: The study was conducted to evaluate and compare the changes in corneal endothelial cell count density (ECD) and Central corneal thickness (CCT) between diabetic and non diabetic population before and after phacoemulsification surgery. Settings and Design: This prospective, comparative, interventional study was carried out at government medical college and attached group of hospitals, a tertiary eye care centre in Rajasthan, India. Materials and Methods: A total of 50 patients with type II diabetes mellitus (age group 30-80 years) and 50 age matched healthy patients of senile cataract with clear cornea without any other ocular pathology were non-randomly selected for Phacoemulsification surgery (phaco) after detailed preoperative assessment. All patients were operated by the same surgeon with phaco chop technique to exclude any surgeon’s related bias. Endothelial cell count, CCT and Coefficient of Variance (CV) was measured with specular microscope pre-operatively and postoperatively at day 1st, 7th, 15th, 1 month, and 3 months serially. Result: Postoperatively, the mean ECD was decreased in both the groups but loss of endothelial cell count was significantly more in diabetic population as compare to non diabetic groups at day 1, day 7, day 15, 1 month and 3 months. CCT was increased on first post-operative day in both the groups, subsequently decreased and then returned back to about same as pre-operative state after 1 month. But postoperatively, the change in mean CCT was not significant between both groups. The difference in % CV was significantly higher in diabetic group as compared to non diabetic group postoperatively. Conclusion: The corneal endothelial cell changes were significantly high in diabetic population as compared to nondiabetic patients. The ECD loss, increase in mean CCT and % CV were more in diabetic population as compared to non diabetic. And patients with diabetes showed slower recovery in endothelial healing as compared to non diabet

Comparison of power-free-chop and phaco-chop techniques for moderate nuclei

BackgroundTo compare the intraoperative and postoperative effects of power-free-chop and phaco-chop techniques for moderate nuclei in phacoemulsification surgery.MethodsSixty patients were evaluated in 2 groups. The power-free-chop technique was performed in Group 1 (30 eyes), and the phaco-chop technique was performed in Group 2 (30 eyes). There were no significant differences between these 2 groups. The cumulative dissipated energy (CDE), time to achieve maximum vision, corneal thickness variation, and time to return to the preoperative values were collected. All parameters were statistically compared in these 2 groups by using the chi-square test and the independent-sample t-test.ResultsThe CDE was 5.53 ± 1.92 J in Group 1 and 7.02 ± 1.77 J in Group 2. After the operation, the mean time to recover to the maximum vision was 2.80 ± 1.42 days in Group 1 and 3.80 ± 1.92 days in Group 2. The mean postoperative corneal thickness increased 36.9 ± 14.74 μm in Group 1 and 46.20 ± 20.67 μm in Group 2. The mean time to return to preoperative pachymetry values was 3.73 ± 1.70 days and 4.83 ± 2.11 days in Group 1 and Group 2, respectively. There were significant differences in these parameters between the groups.ConclusionsThe power-free-chop technique had fewer negative effects on the corneal endothelium, as less ultrasound power was used for moderate nucleus cases. This can accelerate the functional healing process and the return to preoperative physiologic values.

Evaluation of the Corneal Thickness and Endothelial Changes Following Uncomplicated Phacoemulsification in Diabetic and Non-Diabetic Patients by Pentacam and Specular Microscopy

Background: Diabetes mellitus (DM) is an important health problem that induces unrestful complications. It causes significant morbidity owing to specific microvascular complications such as diabetic retinopathy, diabetic cataract, diabetic keratopathy, and diabetic optic nerve diseases. Patients and Methods: This is a prospective, comparative case series study assessing the corneal endothelial status in 20 diabetics and 20 non diabetics before, after 1 day, 1 week and 1 month of uneventful phacoemulsification using phaco-chop technique. Central corneal thickness (CCT), as well as endothelial cell density (ECD), coefficient of variation (CV) and percentage of polymegathism or hexagonality were measured by specular microscopy. The corneal thickness at 0, 2 and 4 mm from center of the cornea and corneal volume at 3, 5 and 7 mm from the center of the cornea. Changes were compared between both groups using pentacam in the same follow up period. Results: Preoperative CCT was found to be significantly higher in diabetic than in non-diabetic group. ECD and CV were insignificantly higher in diabetics in contrast with the percentage of hexagonality, which was found to be insignificantly lower preoperatively. Diabetics showed insignificant higher loss in endothelial cell count as compared to non-diabetics. Furthermore, the diabetics showed a slower recovery trend in the endothelial healing response as evidenced by lower change in the CV%. Postoperative CCT measurements demonstrated no significant variations between groups evidenced by specular microscopy as well as changes in corneal thickness and volume evidenced by pentacam. Conclusion: The present study revealed no significant differences between preoperative and postoperative values neither in terms of mean ECD values, nor in corneal thickness and corneal volume between diabetic patients and nondiabetic patients undergoing phacoemulsification employing phaco-chop technique.

The effect of phacoemulsification of bilateral cataracts, performed at different intervals, on the macular area of the retina

Purpose. A comprehensive assessment of the state of macular retina after phacoemulsification of two eyes performed at different intervals between operations according to optical coherence tomography (OCT) data. Materials and methods. We examined 93 patients (186 eyes) aged 65.7 ± 1.6 years with bilateral age cataract after phacoemulsification of both eyes performed at different intervals between the operations: 1–5 days — 22 patients (44 eyes), 1–3 weeks — 31 patients (62 eyes), 4 or more weeks — 40 patients (80 eyes). Before surgery, visual acuity of the first eye was, on average, 0.38 ± 0.05, while that of the second eye averaged 0.41 ± 0.05. The operations were performed on the «Infiniti Vision System» (Alcon) phacoemulsifier by Ozil technology through a corneal tunnel 2.2 mm long by one and the same surgeon with no complications. The Phaco chop technique was used. All patients underwent retinal examination by Optovue Avante OPT (OPTOVUE, USA) according to the scanning Protocol Raster and, partly, by Retina map (including central retinal thickness and volume of the macula in the 5 mm zone) before the operation, and 1, 2, 4, 12 weeks after surgery, on both eyes. Results. Before surgery, the average central retinal thickness and the volume of the retina in the area of 5 mm, in both operated eyes were almost identical: the first eye revealed 271.0 ± 7.5 μm, and 5.625 ± 0.040 mm3, the second one revealed 270.0 ± 8.5 μm, and 5.628 ± 0.040 mm3. In the postoperative period, the results showed no statistically significant differences (p &gt; 0.05) between the central retinal thickness and volume in the 5 mm zone before and after surgery in both eyes, regardless of the intervals between operations. Conclusion. The absence of a significant difference in the macular retina response to surgery, confirmed by OCT data, indicated the safety of operations on both eyes regardless of the intervals between them.

Scoop and chop - A modified phaco-chop technique for pseudoexfoliation and cataract.

PURPOSE:The purpose is to evaluate the results of the modified direct phaco-chop technique of cataract surgery in eyes with pseudoexfoliation.METHODS:All patients with pseudoexfoliation and visually significant cataract with normal intraocular pressure (IOP) and optic nerve that underwent cataract surgery by the same surgeon using Infiniti®, OZil® Torsional handpiece (Alcon Labs), were included for this retrospective hospital-based study. Direct vertical or horizontal chop technique was used in all cases with parameters set as required for quadrant removal with high vacuum after the initial cleanup of cortex under the capsulorhexis. To allow better visualization of the hardness of the nucleus core, the sides of the lens were scooped out a central well with vacuum with maximum chopping done centrally within the rhexis as the first step to enable better assessment of the depth of burying the chopper for direct chop. Intraoperative details recorded and analyzed included ultrasound time and cumulative dissipated energy. The mean visual acuity and IOP before and after surgery were recorded at 1 day, 1 week, and 1 month. Complications during or after surgery were noted.RESULTS:A total of 138 patients with a mean age of 62 ± 6.7 years underwent phachop technique of phacoemulsification for nuclear cataract grades of nuclear sclerosis 2–4 with significant improvement in visual acuity from baseline (0.26) to 3 months (0.82), P < 0.001. The mean ultrasound torsional amplitude and cumulative dissipated energy (CDE) were greater for brown cataract of grading >3, P = 0.02. A total of 8 patients had intraoperative zonular dialysis in 1 quadrant (none in >1 quadrant), which was not associated with intraoperative vitreous prolapse in 6 eyes.CONCLUSIONS:Direct modified phaco-chop technique may be a safe technique in pseudoexfoliation due to minimal zonular stress with successful outcomes and reduced complications.

A Comparative Study of Central Corneal Thickness and Endothelial Cell Density after Phacoemulsification by ‘Phaco-chop’ and ‘Divide and Conquer’ Techniques

Introduction: Phacoemulsification was introduced by Kelman in 1967. It is one of the most important innovations in ophthalmology. This has now been accepted as gold standard surgical procedure for management of cataract. Divide and conquer technique, described by Gimbel, was the first nucleofractis cracking technique developed. Phoc-chop technique was presented by Kunihiro Nagahara in 1993 at the meeting of America Society of Cataract and Refractive Surgery. Aim: To compare the Central Corneal Thickness (CCT) and endothelial cell density after phacoemulsification by ‘phaco-chop’ and ‘divide and conquer’ techniques. Materials and Methods: The study included 100 patients divided into two groups, each including 50 patients; Group A, where Divide and Conquer was performed, and in Group B Phaco-chop was performed. The mean Absolute PhacoTime (APT), mean Endothelial Cell Count (ECC), mean Endothelial Cell Loss (ECL), corneal thickness and the visual acuity were reported in the two groups both preoperative and postoperative. Results: The mean APT in group A was 27.12±10.15 seconds, and in group B was 16.58±5.11 seconds (p=0.0001). The mean ECC at sixth week postoperative in group A was 2102. 14 cells/mm2 and in group B it was 2365.38 cells/mm2 (p=0.003). There was statistically significant ECL following sixth week postoperatively 16.22% in divide and conquer group and 8.51% in phaco-chop group (p-value=0.0001). A significant increase in the CCT was observed at the immediate postoperative week among the two studied groups; 3.16% in group A and 2.34% in group B, which was statistically significant. The postoperative CCT pachymetry values were returned to near preoperative values at one and a half months postoperative. Conclusion: The phaco-chop technique utilises less phaco time and energy without significant effect on the final surgical outcome. Significant and equal ECL occurs after the two studied techniques. APT and nuclear grade have a positive correlation with higher ECL. CCT increases significantly and equally postoperatively following the two techniques.

Comparison of Phaco-chop and Divide and Conquer Methods in Grade 3-4 Cataract Patients

Purpose: To compare the outcomes of Grade3-4 cataract surgery performed with 2 phacoemulsification techniques (phaco-chop and divide-and-conquer).&#x0D; Setting: Ministry of Health Tuzla State Hospital, Istanbul, Turkey.&#x0D; Design: Prospective randomized clinical trial.&#x0D; Methods: This is prospective and randomized(double blind) study cataract surgery using two different techniques of nuclear fragmentation performed at the Tuzla State Hospital.100 patients eye with nuclear density from grade 3 to 4 were randomly subdivided into 2 groups (phaco-chop and divide-and-conquer). Intraoperative measurements included Phaco time (PT), effective phaco time(EPT), mean phaco power(MPP). Clinical measurements included preoperative and postoperative 1.day , 7. day, 30. day, and 60.day corrected distance visual acuity(BCVA), time to achieve BCVA, corneal edema rate and time to disappear corneal edema.&#x0D; Results: Intraoperative measurements showed significantly less PT, EPT, and corneal edema with the phaco-chop technique than divide-and-conquer techniques in the grade 3-4 cataract density group (P&lt;0.05).&#x0D; Conclusions: 2 techniques may be effective for cataract surgery in mild and moderate cataracts. However, in eyes with hard cataract the phaco-chop technique can be more effective for lens removal, with less Phaco time and corneal edema, then the divide-and-conquer technique.&#x0D; Financial Disclosure: No author has a financial or proprietary interest in any material, method or device mentioned.