Peripheral corneal relaxing incisions based on anterior keratometry from Scheimpflug tomography versus Placido topography during standard cataract surgery.

AIM: To compare the outcomes of peripheral corneal relaxing incisions (PCRIs) based on standardized nomogram using keratometry from Scheimpflug and Placido machines during standard cataract surgery and to assess the astigmatism neutralization potential of PCRIs. METHODS: In this prospective, comparative case series of eyes with keratometric astigmatism between 0.75D to 2.5D, undergoing routine cataract surgery, PCRIs were performed using standardized nomogram and keratometric data from either Scheimpflug or Placido machines. A single eye of 42 consecutive patients was recruited in each group. Data on pre- and postoperative uncorrected distance visual acuity (UDVA), corrected DVA (CDVA), keratometry and refraction were assessed at 10 weeks postoperatively. Refractive and keratometric J0 J45 vectors were also analyzed. RESULTS: Data on 41 and 39 eyes were available in each group, respectively. There was a significant reduction in keratometric astigmatism in both groups. However, between Scheimpflug and Placido groups, there was no difference in postoperative logMAR UDVA [0.15 ± 0.18 vs 0.14 ± 0.16, p = 0.82] and CDVA [0.11 ± 0.11 vs 0.09 ± 0.10, p = 0.58], postoperative spherical equivalent [-0.34D ± 0.40D vs -0.50D ± 0.43D, p = 0.11], keratometric J0 [-0.03 ± 0.39 vs 0.01 ± 0.85, p = 0.67] and J45 [-0.03 ± 0.41 vs 0.01 ± 0.86, p = 0.65] and refractive J0 [0.05 ± 0.46 vs -0.03 ± 0.92, p = 0.47)] and J45 [-0.06 ± 0.49 vs -0.03 ± 0.99, p = 0.82] vectors, reduction of keratometric astigmatism [-0.40D ± 0.55D vs -0.35D ± 1.24D, p = 0.75] and the keratometric astigmatism neutralization potential [38.56 % ± 29.71 % vs 52.66 % ± 44.06 %, p = 0.12]. - CONCLUSIONS: Although PCRIs performed using Scheimpflug or Placido keratometry reduced the keratometric astigmatism significantly during standard cataract surgery. The astigmatic neutralization potentials of PCRIs comparing these two groups were not significantly different and remain low during the early postoperative period.

Posteriorly enclavated iris claw intraocular lens for aphakia: long-term corneal endothelial safety study.

PURPOSE: To report 2 years follow-up experience, corneal endothelial cell loss results, and A constant used in retroiridis-fixated iris-claw aphakic intraocular lens (IOL) secondary implantation to correct aphakia in eyes without adequate capsule support. METHODS: In this prospective, interventional, clinical case series, 16 consecutive eyes of 14 patients (13 adults and 1 child) underwent retroiridis implantation of Artisan iris-claw aphakic IOL (Ophtec BV, Groningen, the Netherlands). Outcome measures included spherical equivalent (SE) of refractive error, uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA) expressed as the logarithm of the minimum angle of resolution (logMAR), endothelial cell density (ECD), and complications, including raised intraocular pressure (IOP) and pigment dispersion. RESULTS: All eyes were followed up for 2 years postoperatively. Postoperative SE of refractive error was between -1.25 and +1.63 D in all eyes at last follow-up. The mean CDVA was 0.27 ± 0.30 logMAR preoperatively and 0.13 ± 0.21 logMAR at 2 years postoperatively (p = 0.0188). Postoperative UDVA mean was 0.31 ± 0.26 logMAR at last follow-up. Preoperative manual ECD mean of 2269 ± 611 cells/mm2 decreased postoperatively to 2002 ± 532 cells/mm2 at 2 years (p = 0.0005) (mean endothelial cell loss of 11.9 ± 2.0%). No intraoperative complications occurred. There was no significant postoperative IOP increase throughout the follow-up. Iris pigment precipitates on the IOLs occurred in 1 eye (6.3%). No other serious complications occurred. CONCLUSIONS: Two-year results show that retroiridis-fixated iris-claw aphakic IOL implantation is an effective and safe method with regards to corneal endothelial cell loss, and a new A constant is suggested.

Femtosecond laser-assisted lamellar keratoplasty (FSLK) for anterior corneal stromal diseases.

Our objective was to study the outcome of femtosecond-assisted lamellar keratoplasty (FSLK) in stromal corneal diseases. This is a retrospective chart review of 17 patients (20 eyes) who underwent FSLK for anterior corneal pathologies. Main outcome measures were refractive results following FSLK, complications, and graft survival. Mean follow-up time was 42 ± 15 (7-58) months. Preoperative best spectacle-corrected visual acuity (BSCVA) was ≤20/40 in 17 eyes. Postoperative BSCVA ≥ 20/40 was achieved in 12/14 at 12 months, 11/12 at 24 months, and 10/12 eyes at 36 months; postoperative BSCVA ≥ 20/25 was achieved in 8/14, 8/12, and 5/12 eyes at 12, 24, and 36 months, respectively. One eye had vertical gas break through the epithelium during the FSLK. One eye had postoperative epithelial rejection and two eyes had stromal rejection treated successfully with topical steroids. Another eye had epithelial ingrowth that was not progressive; however, the same eye developed bacterial keratitis and scarred graft 32 months post-FSLK. One eye had graft dehiscence and one eye developed excessive interface fibrosis. Five out of 20 grafts failed due to the recurrence of the original disease (3), corneal scarring (1), and excessive interface fibrosis (1). FSLK provides many advantages over conventional PK and DALK, with faster visual rehabilitation and emmetropization of the manifest refraction rather than inducing ametropia and irregular astigmatism.

Intraocular pressure control with Ahmed glaucoma drainage device in patients with cicatricial ocular surface disease-associated or aniridia-related glaucoma.

To analyze the control of intraocular pressure (IOP) with an Ahmed glaucoma drainage device (AGDD) in two groups of glaucoma patients--one with cicatricial ocular surface disease (COSD) and one with aniridia. This is a retrospective comparative case series of nine patients (11 eyes) with COSD and six patients (8 eyes) with aniridia who underwent AGDD surgery to control IOP. The main outcome measure in both groups was stability of IOP between 6 and 21 mmHg. Mean IOP decreased significantly in both groups after AGDD surgery (29.6 ± 8.7 vs 14.7 ± 2.5, p = 0.008 in the COSD group; 26.3 ± 8.2 vs 15.3 ± 5.8, p = 0.008 in the aniridia group). Over a mean post-surgery follow-up of 37.1 months in the COSD group, we managed to control IOP in nine eyes; IOP control was successful in 87 % of eyes at 12 months and 58 % of eyes at 26 months. Over a mean post-surgery follow-up of 37.4 months in the aniridia group, we managed to control the IOP in seven eyes; IOP control was successful in 87 % of eyes at 12 months. AGDD surgery had no significant deleterious effect on visual acuity in either group. A severe complication occurred in one eye (1/8) in the aniridia group (lost vision due to retinal detachment) and in one eye (1/11) in the COSD group (tube exposure). AGDD surgery is effective in controlling IOP and has a low complication rate in COSD and aniridia patients; however, some of the complications are severe and prompt management is needed to prevent deleterious results.

Intraocular pressure control and corneal graft survival after implantation of Ahmed valve device in high-risk penetrating keratoplasty.

PURPOSE: To analyze the control of intraocular pressure (IOP) and corneal graft survival after implantation of Ahmed glaucoma device (AGD) in eyes that had high-risk penetrating keratoplasty (PK). METHODS: This is a retrospective noncomparative case series of 59 eyes that had high-risk PK and underwent AGD insertion. The primary outcome measures are the control of IOP between 6 and 21 mm Hg and corneal graft survival. The secondary outcome measures are risk factors associated with IOP control and corneal graft survival. RESULTS: The mean IOP reduced significantly after the AGD procedure (26.45 ± 6.8 mm Hg preoperatively vs. 16.85 ± 7.4 mm Hg, 16.95 ± 4.6 mm Hg, 17.97 ± 5.7 mm Hg, 15.78 ± 5.2 mm Hg, and 15.59 ± 5.5 mm Hg, at 1 month, 6 months, 1 year, 2 years, and at the last follow-up postoperatively; P < 0.0001). Over a median follow-up of 78 months (range, 9-175 months) after AGD insertion, IOP control was successful in 44 eyes (75.8%). IOP control was successful in 96% of the eyes at 1 year, 87% at 2 years, 83% at 3 years, and 83% at 5 years. The percentage of clear corneal grafts after 1, 2, 3, and 5 years following the AGD insertion were 87%, 77%, 65%, and 47%, respectively. Further surgery after AGD insertion was associated with 1.79 times greater risk of failure of IOP control. CONCLUSIONS: AGD was effective in controlling the IOP associated with high-risk PK over a 5-year period. Postvalve surgery doubles the risk of failure of IOP control.

Comparison of equivalent keratometric indices on Scheimpflug tomography with Placido-based topography system at different optical zones.

AIM: To compare Holladay equivalent keratometric indices on Scheimpflug tomographer and keratometry on Placido topographer at different optical zones. METHODS: In this observational study, 50 right eyes of 50 patients were recruited. All patients were scanned on both machines. Data on K1, K2, mean keratometry (Km) and meridian of steepest keratometry (MoSK) were collected for central 3 mm and 5 mm optical zones from Holladay Equivalent keratometry report on Scheimpflug tomographer and keratometric data from Placido topographer. Difference (Diff(S-P)) in Km and MoSK were calculated by subtracting corresponding values of Placido from Scheimpflug scans. Concordance was evaluated using paired t tests, the Pearson correlation and Bland-Altman analyses. RESULTS: Comparing 3 mm vs 5 mm optical zones on each machine, there was no significant difference in Km and MoSK values but Km showed good correlation unlike MoSK. Comparing Scheimpflug versus Placido, Km showed good correlation at all scan sizes, unlike MoSK. 95% limits of agreement between the machines for Km was -1.20D to 1.08D(3 mm) and -1.46D to 1.23D(5 mm); whereas, for MoSK it was -83.05 to 85.82°s(3 mm) and -107.9 to 77.48°s(5 mm) respectively. The Diff(S-P) for Km at 3 mm (-0.45±0.79) was significantly less than that at 5 mm (-0.10±0.70) (p<0.01) whereas Diff(S-P) for MoSK were not significantly different at both optical zones. CONCLUSIONS: Mean keratometry correlated well between Scheimpflug and Placido scans. Axes showed poor correlation between optical zones on same machine and between the machines with same optical zone. Scheimpflug showed flatter keratometry at smaller optical zone. These machines cannot be used interchangeably in refractive surgery.

Outcomes of pseudophakic toric intraocular lens implantation in Keratoconic eyes with cataract.

PURPOSE: To evaluate the outcomes of pseudophakic toric intraocular lens (IOL) implantation in eyes with stable keratoconus and cataract. METHODS: Retrospective, noncomparative, case series of 12 eyes from 9 patients (mean age: 63.4±3.5 years) with stable mild to moderate keratoconus and cataract who underwent pseudophakic toric IOL implantation (AT TORBI 709M, AcriTec). Uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), manifest refraction, keratometric findings, adverse events, and postoperative complications were recorded for all eyes. RESULTS: Mean postoperative follow-up was 9.0+8.8 months. At last postoperative follow-up, UDVA was 20/40 or better in 75% and CDVA was 20/40 or better in 83.3% of eyes. Postoperative mean refractive sphere (pre- vs postoperative: -4.80±5.60 vs 0.30±0.50 diopters [D]) and cylinder (pre- vs postoperative: 3.00+1.00 D vs 0.70+0.80 D) were significantly better (P<.01 for both). No intra- or postoperative complications occurred. No eyes had progression of keratoconus or significant IOL rotation at postoperative follow-up. CONCLUSIONS: Pseudophakic toric IOLs are an effective option and provide good vision in eyes with stable mild to moderate keratoconus and cataract.

Endothelial keratoplasty: case selection in the learning curve.

PURPOSE: Many corneal surgeons are making the transition from penetrating keratoplasty to endothelial keratoplasty techniques such as Descemet's stripping endothelial keratoplasty and Descemet's stripping automated endothelial keratoplasty in the routine treatment of corneal endothelial failure. Donor dislocation is the commonest complication of these newer techniques. We set out to determine whether preoperative lens/iris diaphragm integrity might influence the rate of donor dislocation and whether donor endothelial failure was more common after surgical intervention for donor dislocation. DESIGN: A retrospective multisurgeon comparative case series from a large teaching and referral center. PARTICIPANTS: Ninety-three eyes of 85 patients: consecutive cases of Descemet's stripping endothelial keratoplasty (n = 77) or Descemet's stripping automated endothelial keratoplasty (n = 16) performed between March 2004 and January 2007. METHODS: A retrospective review of case notes. MAIN OUTCOME MEASURES: The number of eyes with an open communication between the anterior and posterior chambers (an iridectomy or lens capsular defect not covered by a posterior chamber intraocular lens), the number of eyes requiring surgical intervention to correct donor dislocation, and the number of eyes with donor endothelial failure within the follow-up period. RESULTS: Complete data sets were available for analysis in 89 eyes. The median follow-up interval at the time of the audit was 7 months (range 1-34 months). Donor dislocation was significantly more common (P = 0.017) in eyes with an open communication between the anterior and posterior chambers, occurring in 11 of 25 cases (44%) versus 12 of 64 cases (19%) with an intact iris/lens diaphragm. Early endothelial failure was significantly more common (P = 0.011) in cases requiring additional surgical intervention for donor dislocation, occurring in 6 of 21 cases (29%) after successful surgical reattachment of a dislocated donor disc versus 4 of 67 cases (6%) in which no additional intervention was required. CONCLUSIONS: Donor dislocation after endothelial keratoplasty is more common in cases with an open communication between the anterior and posterior chambers. The risk of donor endothelial failure is increased in cases of donor dislocation. Trainee surgeons and surgeons in making the transition from penetrating keratoplasty should initially select cases with an intact lens/iris diaphragm.

Management of angle-supported intraocular lens and iridectomy in Descemet-stripping endothelial keratoplasty.

PROBLEM: Effective tamponade of a Descemet-stripping endothelial keratoplasty graft with a gas bubble requires that there is no route for the bubble to escape into the posterior chamber. SOLUTION: Exchange the angle-supported anterior-chamber intraocular lens (IOL) for an iris-enclaved Artisan IOL and position the IOL haptics over the peripheral iridectomy to occlude it to the extent that no gas can pass.