Software-based assessment of postoperative rotation of toric intraocular lens.

A specially designed grid and software used to assess the postoperative rotation of a toric intraocular lens (IOL) are described. Postoperatively, a digital retroillumination image of the patient is taken and this image is superimposed on the grid. The software determines the center of the IOL. A prominent episcleral vessel is identified, and the axis of the toric IOL and the episcleral vessel are documented using the grid. These values act as references for aligning the images taken during the follow-up period.

DisCoVisc versus the soft-shell technique using Viscoat and Provisc in phacoemulsification: randomized clinical trial.

PURPOSE: To compare the effects and outcomes of DisCoVisc (hyaluronic acid 1.6%-chondroitin sulfate 4.0%) with those of the soft-shell technique using Viscoat (sodium hyaluronate 3.0%-chondroitin sulfate 4.0%) and Provisc (sodium hyaluronate 1.0%) in phacoemulsification. SETTING: Iladevi Cataract & IOL Research Centre, Ahmedabad, India. METHODS: This prospective randomized clinical trial comprised 100 eyes having phacoemulsification by the same surgeon using a standardized technique. Eyes were randomly assigned to DisCoVisc (Group 1) or Viscoat and Provisc (Group 2). Preoperative and postoperative examinations included absolute change in pachymetry, percentage difference in endothelial cell density (ECD) and coefficient of variation (CV), and anterior segment inflammation. RESULTS: The mean postoperative central corneal thickness (CCT) in Group 1 and Group 2 was 590.96+/-46.05 microm and 586.94+/-50.57 microm, respectively, at 1 day; 554.14+/-35.45 microm and 551.65+/-37.69 microm, respectively, at 7 days; and 533.74+/-29.12 microm and 536.44+/-35.59 microm, respectively, at 1 month. The between-group differences in CCT were not statistically significant. At 3 months, the mean ECD was 2427.06+/-243.26 cells/mm2 and 2475.30+/-222.83 cells/mm2, respectively, and the mean CV, 42.38+/-7.94 cells/mm2 and 41.66+/-7.71 cells/mm2, respectively. There was no significant difference in the mean ECD between preoperatively and 3 months postoperatively or in corneal thickness between preoperatively and 1, 7, and 30 days postoperatively. CONCLUSION: A single injection of DisCoVisc was effective, and its postoperative outcomes were comparable to those of combined Viscoat and Provisc.

Comparative quantification of ingress of trypan blue into the anterior chamber after microcoaxial, standard coaxial, and bimanual phacoemulsification: randomized clinical trial.

PURPOSE: To compare ocular surface fluid ingress into the anterior chamber at the end of microcoaxial, standard coaxial, and bimanual phacoemulsification using trypan blue as the quantifying tracer. SETTING: Iladevi Cataract and IOL Research Centre, Ahmedabad, India. METHODS: This prospective randomized observational study comprised 180 consecutive patients who had microcoaxial, standard coaxial, or bimanual phacoemulsification. Trypan blue was applied over the conjunctival surface, and the amount of ingress was assessed after cortex removal (time point 1) and at the end of the surgery after intraocular lens insertion and stromal hydration (time point 2). Logs of dilution were used for statistical analysis. RESULTS: At time point 1, a statistically significant difference was observed in the ingress of trypan blue in the aqueous aspirate. The bimanual group had the highest ingress and the microcoaxial group, the lowest. The amount of ingress in the standard coaxial group fell between the other 2 groups (P< .001). At time point 2, there was no statistically significant difference between the microcoaxial group and the standard coaxial group (P = 1.00); however, in the bimanual group, trypan blue ingress was statistically significantly higher than in the other 2 groups (P< .001). CONCLUSION: At both time points, trypan blue ingress was statistically significantly higher in the bimanual group than in the standard coaxial and microcoaxial groups. At time point 2, there was no statistically significant difference between the standard coaxial and microcoaxial groups.

Histomorphological and immunofluorescence evaluation of bimanual and coaxial phacoemulsification incisions in rabbits.

PURPOSE: To compare the changes in the histomorphology and immunofluorescence of collagen type I in clear corneal incisions (CCIs) at the end of bimanual and coaxial phacoemulsification in rabbits. SETTING: Iladevi Cataract and IOL Research Centre, Ahmedabad, India. METHODS: In this randomized study, the left eye of 30 rabbits had bimanual phacoemulsification through 1.2 mm CCIs for phaco tip access accompanied by an additional 1.4 mm incision for irrigating chopper access or coaxial phacoemulsification through a 2.6 mm single-plane CCI. The right eyes acted as controls. Samples collected at the end of surgery were processed for histomorphology using periodic acid-Schiff-hematoxylin staining and immunofluorescence localization of type I collagen. RESULTS: Incisions exposed to bimanual phacoemulsification had loss of epithelium, stromal fiber shrinkage, keratocyte nuclei fragmentation and condensation, ragged tunnel margins, and Descemet membrane and endothelial cell loss. The changes were minimal or absent in incisions exposed to coaxial phacoemulsification. Immunofluorescence showed a loss of parallel arrangement of type I collagen fibers in bimanual phacoemulsification incisions, while the fibers were well preserved in coaxial phacoemulsification incisions. The changes were more prominent in the roof of the incision tunnel than in the floor. CONCLUSIONS: Corneal incisions for bimanual phacoemulsification were more prone to damage than those for coaxial phacoemulsification. This may be attributed to the absence of a sleeve, which places the incision tunnel in direct contact with the metal phaco tip.

Ingress of bacterial inoculum into the anterior chamber after bimanual and microcoaxial phacoemulsification in rabbits.

PURPOSE: To compare the amount of bacterial ingress from the ocular surface into the anterior chamber at the end of bimanual and microcoaxial phacoemulsification in rabbits. SETTING: Iladevi Cataract & IOL Research Centre, Raghudeep Eye Clinic, Memnagar, Ahmedabad, India. METHODS: This randomized study comprised 40 eyes of 20 rabbits. Rabbits had microcoaxial phacoemulsification through a 2.2 mm single-plane clear corneal incision or bimanual phacoemulsification through a clear corneal 1.2 mm incision for phaco tip access accompanied by an additional 1.4 mm incision for irrigating chopper access. At the end of lens removal, 0.5 mL of culture suspension of Staphylococcus epidermidis (105 colony-forming units [CFU]/mL) was instilled on the ocular surface and kept for 2 minutes. Next, 0.1 mL of aqueous fluid was collected from the anterior chamber and subjected to a microbial viable count. RESULTS: The microcoaxial group had statistically significantly lower ingress of bacteria than the bimanual group (250.0 CFU/mL and 1538.1 CFU/mL, respectively) (P<.002) irrespective of the presence or absence of wound distortion. CONCLUSION: Bacterial ingress occurred in both groups, although it was statistically significantly higher in the bimanual group.

Contrast sensitivity and glare disability after implantation of AcrySof IQ Natural aspherical intraocular lens: prospective randomized masked clinical trial.

PURPOSE: To evaluate contrast sensitivity and glare disability after implantation of an AcrySof IQ Natural SN60WF aspherical intraocular lens (IOL) (Alcon Laboratories). SETTING: Iladevi Cataract & IOL Research Centre, Ahmedabad, India. METHODS: One hundred twenty consecutive patients who had phacoemulsification in a prospective triple-masked trial were randomized to receive an AcrySof SA60AT IOL (40 eyes), AcrySof Natural SN60AT IOL (40 eyes), or AcrySof IQ SN60WF IOL (40 eyes). At 3 months, contrast sensitivity was measured using the CSV-1000E contrast sensitivity chart test face (Vector Vision) at 3, 6, 12, and 18 cycles per degrees (cpd) under photopic conditions (85 cd/m(2)) and mesopic conditions (2.7 cd/m(2)) with 4.0 mm and 6.0 mm fixed central apertures, with and without glare. The Kruskal-Wallis test was used and a pair-wise comparison performed. The main outcome measure was the difference in contrast sensitivity between IOLs at each spatial frequency. RESULTS: The best corrected visual acuity was similar between the 3 IOL groups (P = .6). The AcrySof IQ group had significantly higher contrast sensitivity at 18 cpd under photopic conditions (P = .008); at 3, 6, 12, and 18 cpd during mesopic testing with a 4.0 mm aperture without glare (P = .018, P = .011, P = .007, and P = .0001, respectively) and with glare (P = .003, P = .006, P = .005, and P = .004, respectively); and at all spatial frequencies during mesopic testing with a 6.0 mm aperture without glare (P = .018, P = .006, P = .009, and P = .0001, respectively) and with glare (P = .019, P = .002, P = .01, and P = .017, respectively). CONCLUSION: Eyes with the AcrySof IQ SN60WF IOL had significantly higher contrast sensitivity than eyes with an AcrySof SA60AT or AcrySof Natural SN60AT IOL at all spatial frequencies during mesopic testing (with and without glare) with 4.0 and 6.0 mm artificial pupil.

Effect of stromal hydration of clear corneal incisions: quantifying ingress of trypan blue into the anterior chamber after phacoemulsification.

PURPOSE: To use trypan blue as a quantifiable ingress tracer to determine whether stromal hydration reduces ocular surface fluid ingress at the end of phacoemulsification. SETTING: Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, India. METHODS: A prospective randomized study included 80 eyes having phacoemulsification through 2.2 mm incisions. These eyes were divided into 2 equal groups: 1 had stromal hydration (surgery completed by injecting fortified balanced salt solution [BSS Plus] to hydrate the lateral walls and internal entry of incision) and the other had no stromal hydration. One half milliliter of 0.0125% sterile trypan blue was instilled on the ocular surface and allowed to remain for 2 minutes. One-tenth milliliter of aqueous fluid was aspirated from the anterior chamber, and its optical density was measured using ultraviolet spectrophotometry. Logs of dilution of trypan blue were used for statistical analysis using the nonparametric Mann-Whitney U test. RESULTS: There was a statistically significant decrease and difference between groups in mean dilution of trypan blue in the aqueous aspirate (P<.001). The mean was 1:11,337 in the stromal hydration group and 1:220 in the no stromal hydration group. Logs of mean dilution of trypan blue had statistically significant lower values in the stromal hydration group than in the no stromal hydration group (3.21 and 2.14, respectively) (P<.001). CONCLUSIONS: Stromal hydration of clear corneal incisions reduced ingress into the anterior chamber of the trypan blue instilled on the ocular surface. Clinically, these findings may have a beneficial effect in reducing the risk for postoperative endophthalmitis.