Gabi Shemesh

HYPERHOMOCYSTINEMIA IN PSEUDOEXFOLIATION GLAUCOMA

PurposeTo determine the prevalence of hyperhomocystinemia in patients with pseudoexfoliation glaucoma. Patients and MethodsThis prospective study included 30 patients with glaucoma and 30 age-matched controls with no history of ocular disease who were undergoing routine physical checkups. Plasma homocysteine levels of all the study participants were determined using high-performance liquid chromatography, and values exceeding 15 &mgr;mol/L were considered elevated. ResultsThe mean plasma homocysteine level was 16.80 ± 3.20 and 12.39 ± 1.97 &mgr;mol/L in glaucoma patients and controls, respectively (P <0.0001). Fifteen glaucoma patients (50%) had hyperhomocystinemia compared with 3 controls (10%) (P = 0.0015). ConclusionHyperhomocystinemia may be associated with pseudoexfoliation glaucoma, which may partially explain the increased risk of vascular diseases among patients with pseudoexfoliation syndrome.

Predictability of Corneal flap thickness in laser in situ keratomileusis using three different microkeratomes

PURPOSE To compare the accuracy and consistency of corneal flap thickness in the right and left eye created by three different widely used microkeratomes during consecutive laser in situ keratomileusis (LASIK). METHODS Corneal thickness of 132 eyes of 66 patients was measured preoperatively and intraoperatively. Corneal flap thickness was calculated by subtracting the corneal stromal thickness from the total corneal thickness. Three different microkeratomes were used for creating the corneal flap: Chiron Automated Corneal Shaper (ACS), Baush and Lomb Surgical Hansatome, and Nidek MK 2000 microkeratomes. The same surgeon performed all procedures on the right eye first and then on the left eye using the same blade and the same surgical technique. RESULTS Mean corneal flap thickness created by the ACS (160-microm depth setting) microkeratome was 128.30 +/- 12.57 microm in the right eye and 122.96 +/- 13.30 microm in the left eye. The Hansatome (160-microm depth plate) microkeratome created a flap of mean 141.16 +/- 20.11 microm in the right eye and 120.95 +/- 26.95 microm in the left eye, and the Nidek MK 2000 (130-microm depth plate) microkeratome created a flap of 127.25 +/- 4.12 microm in the right eye and 127.54 +/- 3.7 microm in the left eye. CONCLUSION Corneal flap thickness tended to be considerably thinner than expected on both eyes using the ACS and Hansatome. With the ACS and Hansatome, the difference in corneal flap thickness between the first and second operated eye was statistically significant. With the Nidek MK 2000 microkeratome, there was no statistically significant difference between the first and second operated eye and measurements were close to desired corneal flap thickness. Intraoperative pachymetry is recommended for every LASIK procedure.

Effect of brimonidine tartrate 0.2% ophthalmic solution on pupil size.

Purpose: To evaluate the effect of brimonidine tartrate 0.2% ophthalmic solution on pupil size under scotopic and photopic luminance conditions in persons considering laser refractive surgery. Setting: Ophthalmic Health Center, Tel Aviv, Israel. Methods: The pupil size was measured in 36 eyes of 36 participants under scotopic and photopic conditions using the Colvard pupillometer (Oasis Medical) before and after brimonidine tartrate drops were administered. The pupil size was subsequently measured after 30 minutes and 4 and 6 hours. Results: No difference was found in pupil size before brimonidine tartrate instillation in eyes with light or dark irides. Before instillation, the mean photopic pupil size was 4.81 mm ± 0.54 (SD) (range 4.0 to 6.0 mm). At 30 minutes, all pupils became miotic, with a mean size of 3.77 ± 0.51 mm (range 3.0 to 5.0 mm) (P<.0001). After 6 hours, 27.8% of the pupils had returned to their previous size. Before brimonidine tartrate administration, the mean scotopic pupil size was 6.22 ± 0.73 mm (range 5.0 to 8.0 mm). There was significant miosis to 4.57 ± 0.84 mm (range 3.0 to 6.5 mm) (P<.0001) that continued for at least 6 hours. The miotic effect of brimonidine tartrate was stronger in eyes with light irides. Conclusions: Brimonidine tartrate caused significant miosis, especially under scotopic conditions, most likely from its &agr;‐2 adrenergic effect. Under photopic luminance conditions, the miotic effect was pronounced.

C-reactive Protein Levels in Normal Tension Glaucoma

To determine C-reactive protein (CRP) levels in patients with normal tension glaucoma (NTG). Methods:This study included 20 cases with NTG and 30 controls, with no history of ocular disease. Plasma CRP levels of all the study participants were determined using a highly sensitive CRP kit. Results:Twenty cases (11 males, 9 females, mean age 69 ± 5 years) with NTG and 30 age-matched controls (15 males, 15 females, mean age 68 ± 6) were evaluated. Both groups had similar demographic parameters (age, sex, BMI). Plasma CRP levels were significantly higher in the NTG cases than in controls (median [range], 3.20 [0.17-8.4] mg/dL compared with 0.5 [0.1-3.2], P < 0.001). The mean plasma CRP level was significantly elevated in the NTG cases compared with the controls (3.21 ± 0.6 mg/dL and 0.85 ± 0.17 mg/dL, respectively, P < 0 0.01). Conclusion:Our findings suggest that higher CRP levels may be associated with NTG. It is possible that a vascular inflammatory process is involved in the etiology of this glaucoma.

The efficacy of selective laser trabeculoplasty versus argon laser trabeculoplasty in pseudophakic glaucoma patients

Introduction: This study evaluated and compared the efficacy of selective laser trabeculoplasty (SLT) and argon laser trabeculoplasty (ALT) in terms of intraocular pressure (IOP)-lowering effects in pseudophakic patients at various time points after treatment. The primary aim was to compare the efficacy of SLT and ALT in reducing the IOP of pseudophakic glaucoma patients who recently underwent successful cataract extraction surgery. The secondary endpoint was to determine the percentage of SLT and ALT patients whose IOP was successfully reduced by at least 15% from baseline. Patients and methods: This study was a follow-up of a prospective randomized clinical trial. Fifty-two eyes from 52 glaucoma patients with uncontrolled IOP who had previously undergone successful phacoemulsification-assisted cataract excision surgery with intracapsular lens implantation were randomly assigned to treatment with either ALT (n = 30) or SLT (n = 22). Fifteen patients were excluded due to adverse events encountered during the study, leaving a total of 18 and 19 patients in the ALT and SLT groups, respectively. IOP measurements were carried out at scheduled intervals until 12 months post-laser treatment. Results: There were no significant differences in the IOP-lowering effects between the two methods at any time point during the follow-up period. The greatest differences between the two groups were observed at 1 week posttreatment and at the 3-month time point, but neither reached a level of significance. At the final checkup, the mean IOP reduction from baseline was 3.23 mmHg in the ALT group and 4.30 mmHg in the SLT group (P = 0.269). At that visit, six (35.3%) patients in the ALT group and 15 (75%) patients in the SLT group had a reduction of ≥15% from their baseline IOP. Conclusion: SLT and ALT are equally effective in their IOP-lowering capabilities in new pseudophakic glaucoma patients during the first 12 months after treatment.

Pressure Phosphene Tonometry Versus Goldmann Applanation Tonometry for Measuring Intraocular Pressure Before and After LASIK

PURPOSE To compare pressure phosphene tonometry with Goldmann applanation tonometry for measuring intraocular pressure (IOP) before and after LASIK. METHODS Forty-three (18 men and 25 women) consecutive healthy patients underwent complete pre- and postoperative LASIK ophthalmologic assessments including manifest and cycloplegic refraction, keratometry, and central corneal thickness. Three repetitive sets of pressure phosphene tonometry and Goldmann applanation tonometry measurements were performed the day before and 3 months following uneventful LASIK. RESULTS Mean preoperative spherical equivalent refraction was -4.70 +/- 2.50 diopters (D) (range: -1.50 to -12.90 D) and mean preoperative keratometry was 43.95 +/- 1.08 D. After LASIK, spherical equivalent refraction was +0.23 +/- 0.11 D and mean keratometry was 39.46 +/- 2.28 D. Preoperative pressure phosphene tonometry (12.16 +/- 1.58 mmHg) and Goldmann applanation tonometry (12.01 +/- 1.55 mmHg) IOP measurements were similar. Postoperative IOP was 10.30 +/- 1.16 mmHg with Goldmann applanation tonometry and 12.20 +/- 1.62 mmHg with pressure phosphene tonometry. The postoperative IOP difference between Goldmann applanation tonometry and pressure phosphene tonometry was 0.15 +/- 1.12 mmHg (P = .41). The mean change in pachymetry after LASIK was 68.73 +/- 73 microm. The change in Goldmann applanation between preoperative and postoperative LASIK values was 1.71 +/- 1.43 mmHg (P < .0001), a change that was strongly correlated with changes in corneal thickness (R = 0.75, P < .0001) and keratometry (R = 0.72, P < .0001). No such correlations were found with pressure phosphene tonometry. CONCLUSIONS Goldmann applanation tonometry-measured IOP decrease after LASIK is strongly correlated with a decrease in central corneal thickness and changes in keratometry, whereas pressure phosphene tonometry-measured IOP is independent of corneal thickness. Pressure phosphene tonometry appears to be a more reliable method for recording tonometry in these patients.

Comparison of corneal flap thickness between primary and fellow eyes using three microkeratomes.

PURPOSE To compare corneal flap thickness created in laser in situ keratomileusis (LASIK) in primary (right) and fellow (left) eyes (same blade for both eyes) using three microkeratomes. METHODS The corneal thickness of 132 eyes (66 patients) was measured preoperatively and intraoperatively after flap creation. Corneal flap thickness was calculated by subtracting stromal bed thickness from total corneal thickness. Three microkeratomes were used: Nidek MK-2000, Bausch and Lomb Surgical Hansatome, and the Chiron Automated Corneal Shaper (ACS). Each patient had both corneas cut by one microkeratome and one blade at the same session. RESULTS Mean corneal flap thickness created in primary eyes was 128.30 +/- 12.57 microm (range 105 to 147 microm) for the ACS (160-microm plate and 8.5-mm ring) and 122.96 +/- 13.30 microm (range 86 to 140 microm) for fellow eyes; Hansatome (160-microm plate and 8.5-mm ring): 141.16 +/- 20.11 microm (range 101 to 169 microm) in primary eyes and 120.95 +/- 26.95 microm (range 107 to 151 microm) in fellow eyes; Nidek (130-microm plate and 8.5-mm ring): 127.25 +/- 4.12 microm (range 116 to 134 microm) in primary eyes and 127.54 +/- 3.7 microm (range 119 to 134 microm) in fellow eyes. The corneal flap in the ACS and Hansatome microkeratomes was always thicker in the primary than the fellow eye, using the same blade for both eyes. No significant difference was found using the Nidek microkeratome. CONCLUSION Corneal flap thickness tended to be thinner in fellow eyes than in primary eyes for the ACS and Hanstome microkeratomes. The Nidek microkeratome results were closer to specified corneal flap thickness than the ACS and Hanstome microkeratomes.

Standard Trabeculectomy and Ex-PRESS Miniature Glaucoma Shunt: A Comparative Study and Literature Review

Purpose:The aim of this study was to compare the efficacy and safety between standard trabeculectomy and the Ex-PRESS shunt implantation. Methods:A retrospective review of the records of 100 eyes of 100 patients who underwent trabeculectomy or Ex-PRESS shunt implantation between July 2010 and June 2012 was conducted. Of these, 61 (61%) eyes underwent trabeculectomy and 39 (39%) eyes underwent Ex-PRESS shunt implantation. Demographic information, glaucoma type, surgical details, preoperative, and postoperative data including intraocular pressure (IOP), number of medications, reoperation, and occurrence of any complications were recorded. Results:No differences in IOP reduction or number of postoperative IOP-lowering medications were demonstrated between the 2 procedures. Success rates were 86.9% for trabeculectomy and 84.6% for Ex-PRESS shunt. Rates of failure and hypotony were not significantly different between the groups. No parameter was correlated with success or failure of any procedure. Conclusions:Standard trabeculectomy and Ex-PRESS shunt have similar efficacy and safety profiles. As the Ex-PRESS shunt is considerably more expensive, its use may be unjustified, especially as a primary procedure.

Measurements of intraocular pressure by Goldmann tonometry, Tonopen XL, and the transpalpebral tonometer, TGDc-01, after penetrating keratoplasty: a comparativye study.

Purpose: The aim of this study was to compare intraocular pressure (IOP) measurements obtained by Goldmann tonometry (GT), the Tonopen XL, and a new transpalpebral tonometer, TGDc-01, in eyes that had undergone penetrating keratoplasty (PKP). Methods: IOP was measured in post-PKP eyes by means of GT, Tonopen XL, and TGDc-01. Central corneal thickness measurements were also obtained for all eyes. Results: Forty-five eyes of 43 patients were enrolled in the study. The mean IOP difference (±SD) was −0.42 ± 5.83 mm Hg between GT and Tonopen and 3.20 ± 7.55 mm Hg between GT and TGDc-01. The correlation coefficient was 0.84 between GT and Tonopen XL (P < 0.001) and 0.71 between GT and TGDc-01 (P < 0.001). Overall 2-way analysis of variance between the means showed no significant differences between the 3 devices (P = 0.077). Conclusions: A closer agreement was found between GT and Tonopen XL in post-PKP eyes. TGDc-01 yielded lower IOP readings than the other 2 devices. It remains uncertain whether this new transpalpebral tonometer is simply inaccurate or whether avoiding contact with the corneal graft by measuring IOP through the eyelid enables it to provide more accurate IOP readings than those obtained by transcorneal techniques.

The efficacy and safety of once-daily versus once-weekly latanoprost treatment for increased intraocular pressure.

We evaluated the efficacy and safety of latanoprost eye drops once-weekly, compared to once-daily for improving patient compliance. Twenty (20) patients (11 women and 9 men), 12 with ocular hypertension and 8 with early glaucoma, were studied after washout of the antiglaucoma treatment. One (1) group was treated with latanoprost once-daily (control). The other group was treated once-weekly (study group). Intraocular pressure (IOP) was measured at baseline and on the 2nd, 4th, 6th, and 9th day after the last drop in the study group, and for 3 months on the same schedule thereafter. The mean baseline IOP was 24.3 +/- 3.9 mmHg in the study group (range, 18-29) and 24.4 +/- 4.4 mmHg in the control group (range, 17-32). The average IOP at all time points of post-treatment was 17.7 +/- 1.5 mmHg (range, 14-23) and 16.9 +/- 2.30 mmHg (range, 13-21), respectively. Latanoprost significantly lowered IOP in both groups (study group, p = 0.005; controls, p = 0.0019). The difference between post-treatment IOP was insignificant in both groups at each time point. The study group had fewer minor side effects than the control group (1/10 versus 6/10, respectively). Latanoprost treatment once-weekly was as effective, and bore fewer minor side effects, as once-daily treatment after 3 months of follow-up.