Surgically Induced Astigmatism and Corneal Higher Order Aberrations in Microcoaxial and Conventional Cataract Surgery

PURPOSE: To compare surgically induced astigmatism (SIA) and some corneal higher order aberrations in patients who underwent microcoaxial cataract surgery (MCCS) or conventional cataract surgery. METHODS: A prospective randomized study included 60 eyes of 55 patients. Thirty eyes received MCCS using a 2.2mm clear corneal incision (group 1), and 30 eyes received conventional cataract surgery using a 2.8 mm clear corneal incision (group 2). SIA and corneal higher order aberrations were measured with a Keratometer (Humphrey, Zeiss) and i-Trace (Tracey Technologies) preoperatively, and at 1 and 3 months after cataract surgery. SIA was analyzed vectorially using the Alpins method. RESULTS: There was no significant difference in preoperative UCVA or BCVA between the two groups. At 1 month and 3 months after surgery, SIA in group 1 was less than that in group 2, but this difference was not significant. There was no statistically significant difference in postoperative change of corneal higher order aberrations in each group at 1 month or 3 months after surgery, and there was no statistically significant difference in corneal higher order aberrations between the two groups preoperatively, at 1 month, or 3 months after surgery. CONCLUSIONS: There was no significant difference in SIA and corneal higher order aberrations between the two groups.

Reproducibility of IntraLASIK Flap Thickness Measured with Optical Coherence Tomography

PURPOSE: To investigate the relationship among optical coherence tomography (OCT), ultrasound pachymetry, and Orbscan in central corneal thickness measurement and to evaluate the reproducibility of flap thickness using an IntraLase femtosecond laser. METHODS: Central corneal thickness was measured by OCT, ultrasound pachymetry, and Orbscan in 59 eyes of 30 patients before LASIK. After IntraLASIK, the corneal flap thickness measured using OCT was compared with the intended corneal flap thickness. RESULTS: Central corneal thickness measured by OCT was thinner than that measured by other instruments preoperatively, but there was no significant difference among these methods (p>0.01), and corneal thickness values obtained by ultrasound pachymetry and Orbscan correlated well with those obtained by OCT (r ranged from 0.804 to 0.889, p0.01). CONCLUSIONS: OCT is a relatively accurate instrument for measuring corneal thickness and can easily measure the corneal flap thickness after LASIK. Compared with the results of a previous study, the mean measured flap thickness in this study was more reproducible with the IntraLase femtosecond laser.

The Potential Role of the Retinal Acuity Meter For Predicting Visual Outcome after Cataract Surgery

PURPOSE: To investigate the accuracy and usefulness of the retinal acuity meter (RAM) in predicting visual acuity after cataract surgery. METHODS: We randomly selected 47 eyes from 43 patients who underwent cataract surgery in our clinic. Preoperative BCVA and 3 month postoperative BCVA were measured by the Snellen chart, and we recorded the preoperative visual acuity by RAM. We also grouped the patients according to diabetic retinopathy and preoperative BCVA 20/100. By comparing the expected visual acuity by RAM with actual postoperative BCVA values, we analyzed the accuracy of the RAM's predictability after surgery. The cataract types and macular disease were taken under consideration when analyzing our results. RESULTS: Of the 47 eyes in our study, the postoperative Snellen visual acuity was predictable within three lines (90.9%) in 11 eyes with diabetic retinopathy and without macular disease. In the 36 eyes without diabetic retinopathy, the postoperative Snellen visual acuity was predictable within three lines (91.6%) of the cases. In both groups, the preoperative RAM acuity and postoperative BCVA were significantly correlated (R2=0.692, R2=0.812, p<0.05). In 41 eyes with preoperative BCVA 20/100 or more, the postoperative Snellen visual acuity was highly predictable in 95.1% (R2=0.763, p<0.05). However, in 6 eyes with preoperative BCVA levels less than 20/100, the postoperative Snellen visual acuity was not predictable (66.6 %). In the patients with both nucleosclerosis and posterior subcapsular opacity and in the patients with additional cortical opacity, the postoperative BCVA differed from the preoperative RAM acuity by more than three lines on the Snellen chart. CONCLUSIONS: RAM is useful in predicting postoperative visual acuity in cataract patients, but may be unreliable in the patients with combined cataract forms or with preoperative BCVAs less than 20/100.

Comparative Assessment of Clinical Results in Various Acrylate IOLs

PURPOSE: To assess the clinical results of various acrylic intraocular lenses (IOLs) after cataract surgery with respect to the tilting and decentration of IOLs, postoperative high-order (HO) aberration, and duration to gain of refractive stability. METHODS: This prospective study comprised 60 eyes of 53 patients after uneventful cataract surgery with IOLs implantation. Patients were randomized into four groups of 15 eyes each based on IOLs type: MA60BM, SA60AT, AR40e, or Akreos. We analyzed the extent of IOL decentration, tilting and the difference between preoperative predictive refraction and postoperative actual refraction at 1 day, 1 week, 1 month and 2 months after surgery. The postoperative HO aberration was determined at 2 months after surgery. RESULTS The extent of IOL decentration and tilting was not statistically significant among any of the groups (p>0.05). The spherical aberrations, the triangular coma aberrations and HO RMS values were, however, statistically significantly different among the groups (p<0.05). Refractive stability was gained by 2 months in all four groups, but the four IOLs differed in the time to refractive stability: 2 months in the MA60BM group, 1 month in the SA60AT group, 1 day in the AR40e group, and 1 week in the Akreos Adapt group. CONCLUSIONS: All four acrylic IOLs provided satisfactory postoperative results, but there were differences in the time to gain of refractive stability and HO aberration between the four IOLs. These results suggest that a surgeon could achieve a better clinical outcome after cataract surgery by selecting the most suitable IOL for his intention.

Comparative Assessment of Clinical Results in Various Acrylate IOLs

PURPOSE: To assess the clinical results of various acrylic intraocular lenses (IOLs) after cataract surgery with respect to the tilting and decentration of IOLs, postoperative high-order (HO) aberration, and duration to gain of refractive stability. METHODS: This prospective study comprised 60 eyes of 53 patients after uneventful cataract surgery with IOLs implantation. Patients were randomized into four groups of 15 eyes each based on IOLs type: MA60BM, SA60AT, AR40e, or Akreos. We analyzed the extent of IOL decentration, tilting and the difference between preoperative predictive refraction and postoperative actual refraction at 1 day, 1 week, 1 month and 2 months after surgery. The postoperative HO aberration was determined at 2 months after surgery. RESULTS The extent of IOL decentration and tilting was not statistically significant among any of the groups (p>0.05). The spherical aberrations, the triangular coma aberrations and HO RMS values were, however, statistically significantly different among the groups (p<0.05). Refractive stability was gained by 2 months in all four groups, but the four IOLs differed in the time to refractive stability: 2 months in the MA60BM group, 1 month in the SA60AT group, 1 day in the AR40e group, and 1 week in the Akreos Adapt group. CONCLUSIONS: All four acrylic IOLs provided satisfactory postoperative results, but there were differences in the time to gain of refractive stability and HO aberration between the four IOLs. These results suggest that a surgeon could achieve a better clinical outcome after cataract surgery by selecting the most suitable IOL for his intention.

The Clinical Results of Hydrophobic Single-Piece Acrylic Intraocular Lenses after Cataract Surgery

PURPOSE: To report the results of the clinical use of single-piece acrylic intraocular lenses (IOLs; AcrySof(R), SA60AT, Alcon) compared with three-piece acrylic IOLs (AcrySof(R), MA60BM, Alcon) after cataract surgery. METHODS: We retrospectively analyzed data of the extent of IOL decentration and tilting measured with Scheimpflug camera (EAS-1000 anterior eye segment analysis system, Nidek) at 1 week, 1 month and 2 months after surgery, the difference in the preoperative predictive refraction and the postoperative actual refraction, and the higher order RMS (root mean square) value with WASCA wavefront analyzer (Carl Zeiss Meditec, Germany) between the two groups (SA60AT group: N=30 , MA60BM group: N=30). RESULTS: The extent of IOL decentration was statistically insignificant in both groups (p>0.05), but the amount of IOL tilting in the SA60AT group was significantly less than that in the MA60BM group at 1 week, 1 month and 2 months postoperatively (p<0.05). There was no statistically significant difference in the preoperative predictive refraction and the postoperative actual refraction between the two groups. The triangular coma aberrations and the higher order (HO) RMS values were, however, significantly less in the SA60AT group (p<0.05). CONCLUSIONS: The SA60AT IOLs provided a better postoperative centration and a smaller HO RMS value than the MA60BM IOLs. Based on these results, we expect that SA60AT IOLs will provide a better clinical outcome in the aspect of quality of vision.

The Role of Nuclear Factor Kappa B on Lens Epithelial Cells after Ultraviolet B Irradiation

PURPOSE: This study was performed to determine the role of nuclear factor kappa B (NF-kappa B) on the lens epithelial cell death after ultraviolet (UV) irradiation. METHODS: Simian virus 40 transfected human lens epithelial cells (HLE B-3 cells) were used in this study. UVB located at 10cm from the bottom was irradiated during 1, 2, 3 and 4 minutes. To measure the cytotoxicity MTT assay was used. Translocation of NF-kappa B was examined by immunocytochemistry with anti NF-kappa B p65 antibody and electrophoretic mobility shift assay (EMSA). To confirm the role of NF-kappa B, the cells were pretreated with sulfasalazine, a specific inhibitor of NF-kappa B, for 30 minutes before irradiation, and cytotoxicity and translocation of NF-kappa B were evaluated. RESULTS: UV irradiation produced a progressive cytotoxic effect in cultured HLE B-3 cells after 1 minute and maximum cytotoxicity was reached after 3 minutes irradiation. When HLE B-3 cells were irradiated with UVB, the translocation of NF-kappa B was observed in immunocytochemistry. These translocations were peaked 6 hours after UV irradiation in EMSA. In HLE B-3 cells pretreated with sulfasalazine, the translocation of NF-kappa B was blocked. The cellular death after UV irradiation was markedly blocked by sulfasalazine. UV irradiation can translocate NF-kappa B and sulfasalazine is a useful blocking agent in this pathway. In addition, sulfasalazine can prevent cellular death after UV irradiation. CONCLUSIONS: These findings suggest that NF-kappa B plays an important role in cellular death after UV irradiation.

A Case of Juvenile Xanthogranuloma of the Corneoscleral Limbus

PURPOSE: Juvenile xanthogranuloma usually affects the anterior uvea before the age of 1 year, and it may less frequently involve the corneoscleral limbus. We report a case of juvenile xanthogranuloma of the corneoscleral limbus in a 7-year-old boy. METHODS: A 7-year-old boy was referred for the evaluation of a painless limbal mass in the left eye, noticed 1 month previously. On examination, the visual acuity was 16/20 (OD) and 10/20 (OS) without correction, and the corrected visual acuity was 20/20 in both eyes. The other ocular findings were normal, except for an elevated, well circumscribed, smooth surfaced mass measured 9x6 mm at the upper temporal corneoscleral limbus of the left eye. After the excision of the mass, the frozen biopsy and the immunohistochemical staining for CD68 and S100 protein were performed. RESULTS: The lesion consisted of a red-brown, vascular, and raised mass. Histopathologically, there was a chronic granulomatous inflammation with stromal fibrosis, which included many giant cells immunoreactive for CD68 and S100 protein. There was no evidence of recurrence during follow-up period of 5 months and 20 months. CONCLUSIONS: The case was diagnosed as juvenile xanthogranuloma by the clinical and histopathologic findings. The juvenile xanthogranuloma of the corneoscleral limbal involvement is very rare and it can be treated with the surgical excision for the purpose of improvement of cosmetic problems without any recurrence. It seems to have very good prognosis when completely excised.