Quantitative evaluation of anterior chamber changes after iridotomy using Pentacam anterior segment analyzer.

PURPOSE: To evaluate changes in anterior chamber morphology with the Pentacam anterior segment analyzer and gonioscopy after laser peripheral iridotomy (LPI) in patients with primary angle closure glaucoma and narrow angle and to compare central corneal thickness measurements performed with Pentacam and ultrasound pachymetry. METHODS: Twenty eyes of 20 patients were enrolled in this prospective interventional study. Before and after LPI, volume, angle, and central and peripheral depth of anterior chamber was quantified with Pentacam. Central corneal thickness was measured with Pentacam and ultrasound pachymetry. RESULTS: Mean central corneal thickness as measured with Pentacam pachymetry was slightly lower than the measurements provided by ultrasonic pachymetry (551.9 microm, range 509-659, versus 556.8 microm, range 520-644) (p=0.93) with an intraclass correlation coefficient of 0.92. Anterior chamber angle increased from 20.32 (standard deviation [SD] 4.2) to 22.31 degrees (SD 3.9). Anterior chamber central depth increased significantly from 1.79 mm (SD 0.22) to 1.85 mm (SD 0.21) and volume changed from 72.18 mm (SD 16.82) to 89.12 mm (SD 12.3), p=0.001. Gonioscopy showed that Shaffer angle widened significantly in all quadrants. Mean intraocular pressure changed from 20.8 mmHg to 18.3 mmHg after LPI (p<0.05). CONCLUSIONS: In patients with primary angle closure glaucoma and narrow angles, anterior chamber volume, angle, and central and peripheral depth, measured with Pentacam, increase significantly after LPI.

Efficacy of Ologen matrix implant in Ahmed Glaucoma Valve Implantation.

To determine the efficacy and safety of the Ologen collagen matrix adjunctive to Ahmed valve surgery. A randomized prospective multicentre clinical trial involving 58 patients that were followed for one year. Conventional surgery with Ahmed valve was performed in 31 eyes (Control group/CG) and in 27 Ologen (Ologen group/OG) was placed over the valve's plate. Baseline data: age, corneal thickness, intraocular pressure(IOP) and antiglaucoma medications.Postoperative data (days 1, 7 and months 1, 3, 6 and 12): IOP, antiglaucoma medications, visual acuity and complications were recorded. Frequency of hypertensive phase, complete and qualified success and survival rate were studied. No differences were found between CG and OG in the baseline data. The only difference between groups was a significantly lower IOP at day 1. No other differences were found in the follow-up between groups. Hypertensive phase (56%CG and 55%OG, p = 0,947), complete success 28,6%CG and 30,4%OG (p = 0,88) and qualified success 96,4% and 95,9%(p = 0,794). Survival rates at 1 year were 76,7%(CG) and 69,2%(OG)(p = 0,531). 38,7% of patients in the CG suffered some complication during follow-up and 61,5% in OG(p = 0,086). Ologen does not increase safety or efficacy in Ahmed valve surgery at one-year follow-up. This is the first study that shows no benefit of Ologen adjunctive to this surgery.

Differences in Corneal Biomechanics in Nonpenetrating Deep Sclerectomy and Deep Sclerectomy Reconverted into Trabeculectomy.

PURPOSE: To evaluate the differences in intraocular pressure (IOP) and in corneal biomechanics in eyes with uneventful nonpenetrating deep sclerectomy (NPDS) in 1 eye and with intended deep sclerectomy reconverted into trabeculectomy (RIT) in the fellow eye of the same patient. PARTICIPANTS: Forty eyes of 20 patients with both types of glaucoma surgery and more than 6 months of follow-up, and 31 eyes of 50 controls. METHODS: IOP was assessed with Goldmann applanation tonometry (GAT), ocular response analizer (ORA), and dynamic contour tonometer (DCT). Student t test for independent samples and a univariate generalized estimating equations model were used to analyze the results. MAIN OUTCOME MEASURES: Overall, no significant differences were found between IOP of NPDS and RIT eyes when measured with 3 tonometers. RESULTS: Although NPDS showed lower values of IOP measured with GAT and ORA, RIT presented lower IOP if DCT is the chosen tonometry. Biomechanically, NPDS eyes had higher corneal hysteresis (CH) and corneal resistance factor (CRF). When compared with control patients, eyes that underwent glaucoma surgery had lower IOP using GAT, DCT and ORA (P<0.001, 0.315, and 0.260, respectively), and lower CRF (P<0.001). CONCLUSIONS: Eyes with NPDS tended to have higher values of CH and CRF and lower IOP than RIT eyes, as measured with 3 of 4 tonometry methods; these differences did not reach statistical significance.

Prospective evaluation of preoperative factors associated with successful mitomycin C needling of failed filtration blebs.

PURPOSE: To study the long-term effectiveness and factors involved in successful needling of failed filtration blebs with mitomycin C (MMC). MATERIALS AND METHODS: We conducted a prospective, nonrandomized comparative trial that included 34 consecutive patients (34 eyes) who underwent mitomycin C needling of a failed filtering bleb after trabeculectomy followed by a 0.01 mL injection of mitomycin C (0.2 mg/ml). The success of the needling revision was defined as absolute if the intraocular pressure (IOP) was < 21 mm Hg without antiglaucoma medications and qualified if the IOP was < 21 mm Hg with antiglaucoma medications. Preoperative and perioperative factors were evaluated for an association with postoperative success using Kaplan-Meier survival analysis. RESULTS: The mean follow-up was 14.2 +/- 9.8 months. The mean preoperative IOP was 25.5 +/- 4.4 mm Hg, which decreased to 11.1, 13.4, 15.8, 16.7, 14.9, 14.1, 13.9, and 13 on postoperative day 1, postoperative week 1, and after 1, 3, 6, 9, 12, and 24 months, respectively (P = 0.001 for each comparison). At the final visit, success was absolute in 15 eyes (44.1%) and qualified in 14 eyes (41.2%). The success rates were 90% and 75% at 1 and 2 years, respectively. The success of the needling procedure was highly correlated with glaucoma filtration surgery performed less than 4 months previously (Kaplan-Meier analysis, log-rank test P = 0.006). CONCLUSIONS: Mitomycin C needling revision appears to have a high long-term success rate. Surgery performed less than 4 months previously contributes to the success of the initial mitomycin C needling procedure.