Analysis of Positional Relationships of Various Centers in Cataract Surgery

PURPOSE: To analyze the positional relationships of various centers in patients undergoing femtosecond laser-assisted cataract surgery (FLACS). METHODS: The locations of the pupil center (PC), limbal center (LC) and lens center were analyzed in each patient using optical coherence tomography during FLACS in 35 eyes of 35 patients. Using the preoperative corneal aberrometry device, angle kappa and the location of the visual axis (VA) were calculated. After acquiring the relative horizontal and vertical coordinates of each center, the distance and location among each center were compared. The relative location and distance of each center were statistically evaluated. RESULTS: The distance from the PC to the lens center was 0.147 ± 0.103 mm, that from the LC to the lens center was 0.205 ± 0.104 mm, and that from the VA to the lens center was 0.296 ± 0.198 mm. The distance from the PC to the VA was 0.283 ± 0.161 mm, that from the LC to the VA was 0.362 ± 0.153 mm, and that from the lens center to the VA was 0.296 ± 0.198 mm. Among the various centers, the PC was the closest to the lens center, whereas the LC and VA were the farthest. Based on the location of the lens center, the PC, LC, and VA exhibited differences in the X and Y coordinate positions (vertical p = 0.004, horizontal p < 0.001). Among them, the LC was significantly inferior and temporal compared to the PC (vertical p = 0.026, horizontal p = 0.023). Based on the location of the VA, the respective locations of the PC, LC and lens center in two dimensions did not significantly differ (vertical p = 0.310, horizontal p = 0.926). CONCLUSIONS: This study demonstrated the positional and locational relationships between the centers regarding FLACS. The locations of the PC, LC, and VA were different from the lens center with the PC being the closest. Surgeons should be aware of these positional relationships, especially in FLACS.

Myopic Shift after Implantation of a Novel Diffractive Trifocal Intraocular Lens in Korean Eyes

PURPOSE: To evaluate the clinical outcomes of cataract surgery using novel diffractive trifocal intraocular lenses (IOLs) in Koreans. METHODS: This was a retrospective, consecutive, interventional study of cataract surgery using POD FineVision IOL implantation. Complete ophthalmologic examinations were performed preoperatively and postoperatively. Defocus curves were assessed over a range of +1.5 to −4.0 diopters in 0.5-diopter steps at one month postoperatively. Uncorrected distant visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, corrected distant visual acuity, distant-corrected intermediate visual acuity, and distant-corrected near visual acuity were assessed one month postoperatively, and manifest refraction was performed during every visit. RESULTS: The study analyzed 31 eyes in 20 patients. There were statistically significant improvements in uncorrected distance visual acuity, uncorrected intermediate visual acuity, uncorrected near visual acuity, corrected distance visual acuity, distance-corrected intermediate visual acuity, and distance-corrected near visual acuity (p < 0.001). The final postoperative refractive outcomes showed statistically significant myopic shifts compared to the target refraction based on SRK/T, SRK-II, Haigis, and Hoffer Q formulas (p < 0.001). CONCLUSIONS: POD FineVision IOLs provide stable visual restoration with improvements of near and intermediate vision in presbyopic eyes. POD FineVision IOLs show myopic shift in a Korean population; therefore, surgeons should be cautious when selecting IOL power in such patients.

Validity of Tono-pachymetry for Measuring Corrected Intraocular Pressure in Non-surgical and Post-photorefractive Keratectomy Eyes

PURPOSE: To assess the validity of central corneal thickness (CCT) and corrected intraocular pressure (IOP) values obtained by tono-pachymetry in non-surgical and post-photorefractive keratectomy (PRK) eyes. METHODS: For the study, 108 young healthy participants and 108 patients who had PRK were enrolled. Measurements were randomly performed by tono-pachymetry, ultrasonic (US) pachymetry, and Goldmann applanation tonometry (GAT). CCT measurement by tono-pachymetry was compared to that of US pachymetry. The corrected IOP value obtained by tono-pachymetry was compared to that obtained by US pachymetry and GAT. The corrected IOP from US pachymetry and GAT was calculated using the identical compensation formula built into the tono-pachymetry. Bland-Altman plot and paired t-test were conducted to evaluate the between-method agreements. RESULTS: The mean CCT measurement using tono-pachymetry was significantly greater by 7.3 µm in non-surgical eyes (p < 0.001) and 17.8 µm in post-PRK eyes (p < 0.001) compared with US pachymetry. Differences were significant in both Bland-Altman plotand paired t-test. The mean difference of corrected IOP values obtained by tono-pachymetry and calculated from measurements by US pachymetry and GAT was 0.33 ± 0.87 mmHg in non-surgical eyes and 0.57 ± 1.08 mmHg in post-PRK eyes. The differences in the Bland-Altman plot were not significant. CONCLUSIONS: The CCT measurement determined using tono-pachymetrywas significantly thicker than that of US pachymetry. The difference in CCT was greater in post-PRK eyes than in non-surgical eyes. However, the corrected IOP value obtained by tono-pachymetry showed reasonable agreement with that calculated from US pachymetry and GAT measurements.

Management of Complication after Hyperopic Laser-assisted in-situ Keratomileusis

PURPOSE: We present a case of a patient who underwent corneal refractive surgery to improve their corrected visual acuity due to a complication of hyperopic laser-assisted in-situ keratomileusis (LASIK). CASE SUMMARY: The patient complained of decreased vision after hyperopic LASIK surgery 12 years prior. The corrected distance visual acuity (CDVA) was 20/200 in the right eye and 20/32 in the left, with manifested refractions of +1.25 +2.00 × 90 and -0.25 +2.00 × 80, respectively. The patient had a with-the-rule astigmatism. The values of corneal and total spherical aberration, which can be determined as coefficients of the Zernike polynomials, were respectively -1.027 µm and -0.773 µm in the right eye and -0.965 µm and -0.881 µm in the left eye. Slit lamp biomicroscopy revealed no remarkable findings. We performed surface ablation surgery to flatten the central cornea of the patient's right eye. At 12 months after surgery, the CDVA of the patient's right eye was 20/30 and the negative corneal spherical aberration was reduced. CONCLUSIONS: Corneal refractive surgery to reduce negative corneal spherical aberration by flattening the central cornea is one of possible treatment options for the reduced corrected distance visual acuity after hyperopic LASIK.

Clinical Outcomes of Cataract Surgery Using Nasal Clear Corneal Incision: Safety and Efficacy

PURPOSE: To compare the safety and efficacy of cataract surgery using nasal clear corneal incision (CCI) versus superior or temporal CCIs in Korean patients. METHODS: A retrospective comparative study was conducted. Patients underwent cataract surgery using CCI performed by 3 surgeons between January 2012 and December 2013.The patients were divided into the following 3 groups based on CCI direction: nasal CCIs (group I), superior CCIs (Group II), and temporal CCIs (Group III). To assess usability, surgically induced astigmatism (SIA), best-corrected visual acuity (BCVA), intraocular pressure (IOP), keratometry reading, and refractive errors at baseline and 1 month after surgery were compared. Operation times were compared between groups. To assess safety, intraoperative complications and wound stability were compared. RESULTS: A total of 1,374 eyes (Group I, 283 eyes; Group II, 587 eyes; Group III, 504 eyes) were included in the present study. The SIA was not significantly different among the 3 groups. The postoperative mean BCVA, IOP, keratometry reading and spherical equivalent as well as the mean operation times were not significantly different between the 3 groups (14.04 ± 3.79 vs. 13.80 ± 3.27 vs. 13.80 ± 3.70; p = 0.473). The rate of intraocular complications and incidence of corneal wound suture were not significantly different between the 3 groups (1.7% vs. 3.2% vs. 2.3%; p = 0.378). CONCLUSIONS: The safety and efficacy of cataract surgery using nasal CCI were not significantly different compared with the use of temporal or superior CCI. Our results showed that cataract surgery using nasal CCI can be performed safely and conveniently in Korean patients.

Comparison of Intracorneal Inlay for Presbyopia Correction: Hydrogel and Small-Aperture Inlays with a Six- Months Follow-Up

PURPOSE: To study the safety and efficacy of corneal reshaping and small-aperture inlays and compare the clinical results. METHODS: From February 2014 to November 2014, 22 corneal reshaping inlays were inserted at Asan Medical Center and from October 2012 to March 2013, 26 small-aperture inlay surgeries were performed: 6 eyes at Asan Medical Center and 20 eyes at Samsung Medical Center. The preoperative and postoperative parameters were reviewed retrospectively and included monocular uncorrected distance visual acuity (UDVA; log MAR), uncorrected near visual acuity (UNVA; log MAR), refraction and corneal curvature based on automated refractor keratometry, reading distance and patient satisfaction. RESULTS: In the hydrogel inlay group, preoperative mean monocular UNVA was 0.83 +/- 0.05 and monocular UDVA 0.07 +/- 0.03. At 6 months, mean monocular UNVA was 0.23 +/- 0.05 and UDVA 0.05 +/- 0.02. The most preferred mean reading distance in the hydrogel inlay group was 39.38 +/- 3.18 cm. In the small-aperture inlay group, preoperative mean monocular UNVA was 0.4 +/- 0.06 and monocular uncorrected visual acuity 0.27 +/- 0.04. At 6 months, mean monocular UNVA was 0.11 +/- 0.02 and UDVA 0.09 +/- 0.05 and the most preferred mean reading distance was 44.23 +/- 5.17 cm. Although 85% of patients in the corneal reshaping inlay group were satisfied or very satisfied, only 20% of patients in the small-aperture inlay group were satisfied. CONCLUSIONS: Both inlays are considered good options for correcting presbyopia. However, postoperative satisfaction score was higher and less glare symptoms were reported in the hydrogel inlay group.

Comparison of Clinical Outcomes after Various Techniques of Intraocular Lens Dislocation Correction

PURPOSE: To compare clinical outcomes of various surgical methods of intraocular lens dislocation correction surgery. METHODS: We retrospectively analyzed the medical records of patients who underwent intraocular lens dislocation correction surgery with and without vitrectomy by two seasoned surgeons, and compared postoperative best corrected visual acuity and spherical equivalent. Clinical outcomes of secondary intraocular lens insertion after primary intraocular lens removal and primary intraocular lens reposition were compared among the cases without vitrectomy. RESULTS: Dislocated intraocular lens correction without vitrectomy showed better postoperative visual acuity compared to procedures with vitrectomy (0.35 +/- 0.37 vs. 0.54 +/- 0.18; t-test, p = 0.001), but there were no significant differences in spherical equivalent (1.30 +/- 1.10 vs. 1.80 +/- 1.57; p = 0.24) between cases with and without vitrectomy. In comparing primary intraocular lens reposition and secondary intraocular lens insertion among the cases without vitrectomy, the outcomes did not show significant differences in best corrected visual acuity (0.28 +/- 0.40 vs. 0.40 +/- 0.37; p = 0.38) or spherical equivalent (1.66 +/- 1.43 vs. 1.07 +/- 0.79; p = 0.19). In comparing secondary intraocular lens insertion into the capsular bag and fixation to the sclera, iris and iris sulcus, the outcomes did not show significant differences in best corrected visual acuity (p = 0.49) or spherical equivalent (p = 0.33). CONCLUSIONS: The various intraocular lens correction methods examined did not show clinically significant differences in best corrected visual acuity and spherical equivalent when performed by experienced surgeons, except for better postoperative best corrected visual acuity in cases without vitrectomy compared to cases with vitrectomy.

Surgical treatment of presbyopia

Presbyopia is the progressive reduction in the ability to focus on near objects, and as an age-related condition, the prevalence of presbyopia is expected to increase with the aging of society. A number of corneal surgical procedures are available for the treatment of presbyopia, including monovision laser in situ keratomileusis (LASIK)/laser-assisted subepithelial keratomileusis (LASEK), conductive keratoplasty, presbyopic LASIK, and corneal inlay. Implantation of presbyopia-correcting intraocular lenses (IOLs), such as refractive/diffractive IOLs or accommodating IOLs, is also an option. Despite the variety of treatment options available, a perfect solution has yet to be developed and patients may present with visual or optical complications such as halos, glare, or decreased contrast sensitivity. As such, careful selection and customization of treatment is essential, based on patients' individual needs and requirements for vision.

Lower Energy to Make a Corneal Flap with a 60 kHz Femtosecond Laser Reduces Flap Inflammation and Corneal Stromal Cell Death But Weakens Flap Adhesion

PURPOSE: To compare corneal flaps created in rabbits with a 60 kHz femtosecond (FS) laser using different levels of raster energy and to measure early inflammation, corneal stromal cell death, and late postoperative adhesion strength. METHODS: Sixty rabbits were divided into three groups of 20 each. A flap 110 micrometer thick and 9.0 mm in diameter was made in one eye of each rabbit at raster energies of 0.7 microJ, 1.1 microJ, and 2.4 microJ. Histopathological evaluation for inflammation and apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed at 4 and 24 hours after flap creation. The adhesion strength of the flaps was measured with a tension meter at 1 and 3 months. RESULTS: Twenty four hours after flap creation, the 2.4 microJ group had more inflammatory and CD11b-positive cells than the 0.7 and 1.1 microJ groups. The number of TUNEL-positive cells increased with raster energy at 4 and 24 hours. The grams of force (gf) needed to detach the flaps at 3 months was significantly higher in 2.4 microJ group (170 gf) than in 0.7 microJ group (97.5 gf) and 1.1 microJ group (100 gf, p = 0.03). CONCLUSIONS: Using raster energy lower than 1.1 microJ to make a flap with a 60 kHz FS laser decreases inflammatory cell infiltration and corneal stromal cell death in the central cornea but may result in a weaker flap than using higher raster energy (2.4 microJ).

Clinical Characteristics of Glaucomatous Subjects Treated with Refractive Corneal Ablation Surgery

PURPOSE: To evaluate the clinical characteristics of newly diagnosed glaucomatous subjects who had a history of refractive corneal ablation surgery (RCAS). METHODS: Sixty-eight glaucomatous subjects who had a history of RCAS and 68 age- and visual field (VF) mean deviation-matched glaucomatous subjects with no history of RCAS were included. Intraocular pressure (IOP), central corneal thickness (CCT), VF, and retinal nerve fiber layer thickness determined by optical coherence tomography were assessed. Parameters were compared between patients with and without a history of RCAS. Between-eye comparisons in the same participant (more advanced vs. less-advanced eye, in terms of glaucoma severity) were performed in the RCAS group. RESULTS: With similar levels of glaucoma severity, those with a history of RCAS showed significantly lower baseline IOP and a thinner CCT than the eyes of individuals without a RCAS history (13.6 vs. 18.7 mmHg, 490.5 vs. 551.7 micrometer, all p < 0.001). However, the extent of IOP reduction after anti-glaucoma medication did not significantly differ between the two groups (17% vs. 24.3%, p = 0.144). In the between-eye comparisons of individual participants in the RCAS group, the more advanced eyes were more myopic than the less-advanced eyes (-1.84 vs. -0.58 diopter, p = 0.003). CONCLUSIONS: Eyes with a history of RCAS showed a similar level of IOP reduction as eyes without such a history after anti-glaucoma medication. Our finding that the more advanced eyes were more myopic than the less-advanced eyes in the same participant may suggest an association between glaucoma severity and myopic regression.

Lower Energy to Make a Corneal Flap with a 60 kHz Femtosecond Laser Reduces Flap Inflammation and Corneal Stromal Cell Death But Weakens Flap Adhesion

PURPOSE: To compare corneal flaps created in rabbits with a 60 kHz femtosecond (FS) laser using different levels of raster energy and to measure early inflammation, corneal stromal cell death, and late postoperative adhesion strength. METHODS: Sixty rabbits were divided into three groups of 20 each. A flap 110 micrometer thick and 9.0 mm in diameter was made in one eye of each rabbit at raster energies of 0.7 microJ, 1.1 microJ, and 2.4 microJ. Histopathological evaluation for inflammation and apoptosis using terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining was performed at 4 and 24 hours after flap creation. The adhesion strength of the flaps was measured with a tension meter at 1 and 3 months. RESULTS: Twenty four hours after flap creation, the 2.4 microJ group had more inflammatory and CD11b-positive cells than the 0.7 and 1.1 microJ groups. The number of TUNEL-positive cells increased with raster energy at 4 and 24 hours. The grams of force (gf) needed to detach the flaps at 3 months was significantly higher in 2.4 microJ group (170 gf) than in 0.7 microJ group (97.5 gf) and 1.1 microJ group (100 gf, p = 0.03). CONCLUSIONS: Using raster energy lower than 1.1 microJ to make a flap with a 60 kHz FS laser decreases inflammatory cell infiltration and corneal stromal cell death in the central cornea but may result in a weaker flap than using higher raster energy (2.4 microJ).

Comparison of Surgical Parameters and Outcomes According to the Phacoemulsification Technique

PURPOSE: To compare intraoperative parameters and postoperative results between divide-and-conquer and multiple phaco-chop technique. METHODS: Two different techniques were performed by one operator on the patients with bilateral cataract. One eye was phacoemulsified by divide-and-conquer technique (D eye), and the other was performed by multiple phaco-chop technique (M eye). Changes of central corneal thickness during the operation, total phaco-time and phaco-energy were measured. RESULTS: Total 29 patients were included. The change of central corneal thickness were 8.4 +/- 11.8 microm in D eye and 11.5 +/- 16.7 microm in M eye, which showed no significant difference (p = 0.350) and total phaco-time were 70.1 +/- 32.9 seconds in D eye and 71.1 +/- 55.0 seconds in M eye, which also showed no significant difference (p = 0.689). However, phaco-energy were 12.4 +/- 8.3 power x s in D eye and 8.4 +/- 9.9 power x s in M eye, and this result showed significantly larger energy when using divide-and-conquer technique (p < 0.001). CONCLUSIONS: There was no significant difference in change of central corneal thickness and phaco-time between two techniques, divide-and-conquer and multiple phaco-chop technique. However, significantly smaller phaco energy was used by multiple phaco-chop technique compared with divide-and-conquer technique.

Clinical Characteristics of Glaucomatous Subjects Treated with Refractive Corneal Ablation Surgery

PURPOSE: To evaluate the clinical characteristics of newly diagnosed glaucomatous subjects who had a history of refractive corneal ablation surgery (RCAS). METHODS: Sixty-eight glaucomatous subjects who had a history of RCAS and 68 age- and visual field (VF) mean deviation-matched glaucomatous subjects with no history of RCAS were included. Intraocular pressure (IOP), central corneal thickness (CCT), VF, and retinal nerve fiber layer thickness determined by optical coherence tomography were assessed. Parameters were compared between patients with and without a history of RCAS. Between-eye comparisons in the same participant (more advanced vs. less-advanced eye, in terms of glaucoma severity) were performed in the RCAS group. RESULTS: With similar levels of glaucoma severity, those with a history of RCAS showed significantly lower baseline IOP and a thinner CCT than the eyes of individuals without a RCAS history (13.6 vs. 18.7 mmHg, 490.5 vs. 551.7 micrometer, all p < 0.001). However, the extent of IOP reduction after anti-glaucoma medication did not significantly differ between the two groups (17% vs. 24.3%, p = 0.144). In the between-eye comparisons of individual participants in the RCAS group, the more advanced eyes were more myopic than the less-advanced eyes (-1.84 vs. -0.58 diopter, p = 0.003). CONCLUSIONS: Eyes with a history of RCAS showed a similar level of IOP reduction as eyes without such a history after anti-glaucoma medication. Our finding that the more advanced eyes were more myopic than the less-advanced eyes in the same participant may suggest an association between glaucoma severity and myopic regression.

Clinical Outcome of in-the-Bag Single-Piece Aspheric Intraocular Lens Implantation after Microincision Cataract Surgery

PURPOSE: To evaluate the stability and optical performance of the newly developed single-piece aspheric intraocular lens (IOL) by comparing the clinical outcome of the aspheric IOL with the new optic profile design (HOYA iSert, HOYA iMics) and the aspheric IOL (Akreos MI60), which has been proven effective and safe. METHODS: iSert, iMics, and MI60 were inserted into 55 eyes, 60 eyes, and 50 eyes, respectively, after microincision phacoemulsification cataract surgery. Best corrected visual acuity (BCVA), refraction in spherical equivalent, anterior chamber depth (ACD), total higher order aberration (HOA), contrast sensitivity, and surgically induced astigmatism (SIA) were measured and each IOL was evaluated on the functional stability, anterior-posterior stability, centration in the capsular bag, and quality of vision. RESULTS: No statistical differences in preoperative and postoperative BCVA among the 3 IOL groups were observed, however, MI60 showed significant myopic shift postoperatively. Anterior-posterior stability assessed with postoperative change in refractive error and ACD was slightly lower in the MI60 group. In terms of vision quality, while total aberration, total HOA, coma aberration, and contrast sensitivity for the 3 IOLs were not different significantly, spherical aberration of the MI60 group was higher than the other groups at 6 months postoperative. SIA was significantly increased in eyes implanted with iSert than in eyes with iMics or MI60 at 1 month postoperatively, however, the differences were no longer evident after 3 months postoperatively. CONCLUSIONS: The new aspheric IOLs, iSert and iMics, showed good stability and visual outcome equal to MI60 at the 6-month postoperative follow-up.

Comparison of Six-Month Outcomes in Eyes with Two Hydrophilic Aspheric Intraocular Lenses after Cataract Surgery

PURPOSE: To compare the six-month clinical outcomes of Tek-Lens II model 872 (Tekia, Inc.) and Akreos MI-60 (Bausch & Lomb, Inc.) hydrophilic aspheric intraocular lenses (IOLs) implanted in-the-bag. METHODS: After phacoemulsification was performed by a single surgeon (JY Kim), two different hydrophilic aspheric IOLs were implanted: the Tek-Lens II IOL in 57 eyes and the MI60 IOL in 49 eyes. The best corrected visual acuity (BCVA), refractive error (RE), total high-order aberration (HOA), anterior chamber depth (ACD), and contrast sensitivity (CS) were measured preoperatively and one, three, and six months postoperatively. All parameters were analyzed using the independent t-test to compare the two IOL groups. RESULTS: There was no significant difference in the BCVA, RE, or HOA between the two groups at any of the follow-up visits. Three months postoperatively, the ACD of the TEK-Lens II group as measured by corneal topography was significantly shallower than that of the MI60 group (3.67 +/- 0.52 mm vs. 4.10 +/- 0.40 mm; p = 0.008), and most of the photopic CS in the Tek-Lens II group was significantly higher than that in the MI60 group (all p < 0.05). CONCLUSIONS: The Tek-Lens II IOL showed comparable clinical outcomes with a proven hydrophilic aspheric IOL for the postoperative six months.

Clinical Outcomes of Aspheric 1-Piece (Tecnis(R) ZCB00) and 3-Piece (Tecnis(R) ZA9003) Aspheric Intraocular Lens for 12 Months

PURPOSE: To evaluate the postoperative outcome of Tecnis(R) ZCB00 1-Piece acrylic intraocular lens (IOL), the new single piece, aspheric IOL until 12 months. METHODS: Sixty eyes undergone cataract surgery using two different IOLs; The Tecnis(R) ZCB00 1-Piece Acrylic IOL (30 eyes) and the Tecnis(R) ZA9003 3-Piece Acrylic IOL (30 eyes). Cataract surgery was performed in the same period. All complicated cases were excluded. Best corrected visual acuity (BCVA), refractive error, photopic and mesopic contrast sensitivity, total high order aberration, spherical aberration and anterior chamber depth were measured preoperatively and at 1, 6 and 12 months after surgery. RESULTS: There were no statistically significant differences between two groups in BCVA, refractive error, total high order aberration and spherical aberration all the time after surgery. Both groups have negative ocular spherical aberration until 12 months after surgery. 1-piece and 3-piece groups had different tendency in axial movement. But there were no statistically significant differences in anterior chamber depth measured at 1 week, 1, 6 and 12 months after surgery. There was no statistically significant difference in contrast sensitivity at 1, 6 and 12 months after surgery. CONCLUSIONS: The Tecnis(R) ZCB00 1-Piece acrylic intraocular lens (IOL) showed comparable clinical outcomes to the Tecnis(R) ZA9003 3-Piece acrylic intraocular lens (IOL) until 12 months after cataract surgery. 1-piece and 3-piece IOL group had different tendency in axial movement. However, refraction remained stable during 12 months after surgery. Mostly, both IOL groups had negative ocular spherical aberration during whole follow-up period.

Estimation of Corneal Spherical Aberration from Topography

PURPOSE: To formulate an equation to estimate corneal spherical aberration using Orbscan (Bausch & Lomb Surgical, Rochester, NY, USA) parameters. METHODS: The study was carried out retrospectively. The participants were 76 eyes of 76 senile cataract patients with the mean age of 57.37 +/- 17.63 years. Both Orbscan and KR-1W (Topcon Corp, Tokyo, Japan) were taken as preoperative examinations. Correlation analysis between various parameters from Orbscan and corneal spherical aberrations for a 6 mm pupil by KR-1W was performed. And multivariable linear regression was performed with the significantly correlated Orbscan parameters from the correlation analysis. RESULTS: The mean corneal spherical aberration from KR-1W system was 0.25 +/- 0.08 microm. As a result of the multivariable linear regression, we could generate following equations. If the Q-value was available, estimated corneal spherical aberration = 0.389 x Q-value + (0.022 x Axial power 3 mm) - 0.633 (R2 = 0.436). If the Q-value was not available, estimated corneal spherical aberration = 0.184 x (Mean power 5 mm - Mean power 3 mm) + (0.02 x Axial power 3 mm) - 0.563 (R2 = 0.429). By using the equations, 93.4-94.7% of subjects were in the error range of 0.10 microm. CONCLUSIONS: Even when equipped with Orbscan only, an appropriate aspheric intraocular lens can be selected using the estimated corneal apherical aberration by the equations.

Visual Function and Patient Satisfaction in Pseudophakic Monovision

PURPOSE: To evaluate visual performance as well as patient satisfaction and to explore factors associated with clinical outcomes in pseudophakic monovision acquired after bilateral phacoemulsification and sequential monofocal intraocular lens (IOL) implantation. METHODS: The present retrospective study examined patients with pseudophakic monovision. Preoperative and postoperative binocular uncorrected distant visual acuity (UCDVA), uncorrected near visual acuity (UCNVA), refractive errors and postoperative near stereopsis were measured. Postoperative measurements were obtained at least 6 months after the fellow eye surgery. Patient satisfaction and independence from glasses were evaluated using a questionnaire. RESULTS: Preoperative and postoperative binocular UCDVA, UCNVA, and differences in spherical equivalent refractive error were statistically significant. Postoperative near stereopsis was 107.1 arcsec. Questionnaire responses showed that 71.4% of patients were less dependent on glasses and 85.7% were satisfied with the postoperative visual performance. Various designs of monovision, such as crossed monovision or customized minimonovision with moderate myopic defocus showed the same level of patient satisfaction. Patients who were older than 60 years or had poorer preoperative binocular UCDVA showed higher satisfaction. CONCLUSIONS: Pseudophakic monovision is an effective approach for managing loss of accommodation after cataract surgery, especially in patients older than 60 years.

Clinical Outcomes after Combined Ahmed Glaucoma Valve Implantation and Penetrating Keratoplasty or Pars Plana Vitrectomy

PURPOSE: To evaluate whether a combination of penetrating keratoplasty (PKP) or pars plana vitrectomy (PPV) and Ahmed glaucoma valve (AGV) implantation affords a level of success similar to that of AGV implantation alone. METHODS: Eighteen eyes underwent simultaneous PPV and AGV, 14 eyes with PKP and AGV and 30 eyes with AGV implantation alone were evaluated. Success was defined as attainment of an intraocular pressure (IOP) >5 and <22 mmHg, with or without use of anti-glaucoma medication. Kaplan-Meier survival analysis was performed to compare cumulative survival between the combined surgery groups and the AGV implantation-alone group. Cox proportional hazard regression analysis was conducted to identify factors predictive of success in each of the three groups. RESULTS: Mean (+/-standard deviation) preoperative IOP was 30.2 +/- 10.2 mmHg in the PKP + AGV, 35.2 +/- 9.8 mmHg in the PPV + AGV, and 36.2 +/- 10.1 mmHg in the AGV implantation-alone group. The cumulative success rate at 18 months was 66.9%, 73.2%, and 70.8% in the three groups, respectively. Neither combined surgery group differed significantly in terms of cumulative success rate compared with the AGV implantation-alone group (p = 0.556, p = 0.487, respectively). The mean number of preoperative anti-glaucoma medications prescribed was significantly associated with success in the PKP + AGV implantation group (hazard ratio, 2.942; p = 0.024). CONCLUSIONS: Either PKP or PPV performed in conjunction with AGV implantation afforded similar success rates compared to patients treated with AGV implantation alone. Therefore, in patients with refractory glaucoma who have underlying corneal or retinal pathology requiring treatment with PKP or PPV, AGV implantation can be performed simultaneously.

Long-term Clinical Outcomes of Femtosecond LASER-Assisted Descemet's Stripping Endothelial Keratoplasty

PURPOSE: To evaluate the long-term clinical outcomes of femtosecond LASER-assisted Descemet's stripping endothelial keratoplasty (DSEK). METHODS: The clinical results of endothelial keratopathy from 11 consecutive patients who were followed up for at least 12 months after femtosecond LASER-assisted DSEK were retrospectively analyzed. The best corrected visual acuities (BCVA), manifest refractions, intraocular pressures, and perioperative complications were evaluated preoperatively and up to 24 months after the femtosecond LASER-assisted DSEK. RESULTS: The average follow-up period was 18 months. Postoperative visual acuity had significantly improved from 1.26 (logMAR) to 0.80 (logMAR) at 3 months (p < 0.05) and this change was maintained during postoperative follow-up. All eyes underwent successful transplantation and the donor discs were well-attached. The mean endothelial cell density continued to decrease during the follow-up period. The donor-recipient stromal interface was the area where varying degree of haziness and birefringent particles were found. CONCLUSIONS: The femtosecond LASER-assisted DSEK was effective in creating an endothelial donor disc which resulted in rapid visual recovery and low surgically-induced astigmatism. However, the operation caused rapid decrease in endothelial cell density which requires continuing further consideration by the physician.