Clinical outcomes of Ahmed glaucoma valve in anterior chamber versus ciliary sulcus.

PurposeTo evaluate the outcomes of Ahmed glaucoma valve (AGV) tube insertion through the anterior chamber angle (ACA) or through the ciliary sulcus (CS).Patients and methodsIn this case-control study, we retrospectively reviewed the charts of consecutive glaucoma patients who had undergone AGV implantation either through the ACA or the CS between March 2009 and December 2014. The main outcome measures were intraocular pressure (IOP), number of glaucoma medications prescribed, best corrected visual acuity (BCVA), glaucoma type, success rate, complications, and survival ratios. Statistical analysis was carried out using SPSS.ResultsThere were 68 eyes in the ACA group and 35 eyes in the CS group. There were no significant differences between the groups for age, sex, laterality, IOP, preoperative glaucoma medication number, BCVA or glaucoma type (P>0.05). The postoperative follow-up period was 27.2±16.5 months and 30.2±17.7 months for the ACA and the CS groups (P=0.28); IOP values were significantly reduced at the last visit to 16.4±7.2 mm Hg and 14.4±6.8 mm Hg. The difference in the last-visit IOP between the groups was not significant (P=0.06), but the IOP reduction ratio was higher in the CS group (P=0.03). There was no significant difference in the number of postoperative medications (P=0.18). Postoperative complications were similar, but the incidence of flat anterior chamber was higher in the ACA group (P=0.05).ConclusionsThe use of an AGV can control IOP in the majority of cases whether placed in the ACA or the CS. The IOP reduction ratio seemed to be higher in the CS group.

Hyperthyroidism and severity of orbital disease do not change the central corneal thickness in Graves' ophthalmopathy.

PURPOSE: To investigate whether the central corneal thickness (CCT) shows alterations in Graves disease and Graves ophthalmopathy (GO) cases according to the disease severity and hormonal status of the patients. METHODS: A total of 150 patients (62 male, 88 female) with Graves disease and 32 control subjects (11 male, 21 female) were included in the study. The patients were divided into six groups according to the severity of orbital involvement and thyroid hormone status. Best-corrected visual acuity, pupillary responses, color vision, biomicroscopy, CCT, intraocular pressure, and funduscopy were performed, and proptosis was measured with Hertel exophthalmometry in all patients. RESULTS: CCT values of patients with Graves disease and patients with GO with hyperthyroid or euthyroid hormonal status showed no statistical difference among themselves and versus control subjects (p>0.05). CONCLUSIONS: Hyperthyroidism or severity of orbital disease does not affect the CCT.

Hyperthyroidism and severity of orbital disease do not change the central corneal thickness in Graves'' ophthalmopathy.

PURPOSE: To investigate whether the central corneal thickness (CCT) shows alterations in Graves disease and Graves ophthalmopathy (GO) cases according to the disease severity and hormonal status of the patients. METHODS: A total of 150 patients (62 male, 88 female) with Graves disease and 32 control subjects (11 male, 21 female) were included in the study. The patients were divided into six groups according to the severity of orbital involvement and thyroid hormone status. Best-corrected visual acuity, pupillary responses, color vision, biomicroscopy, CCT, intraocular pressure, and funduscopy were performed, and proptosis was measured with Hertel exophthalmometry in all patients. RESULTS: CCT values of patients with Graves disease and patients with GO with hyperthyroid or euthyroid hormonal status showed no statistical difference among themselves and versus control subjects (p>0.05). CONCLUSIONS: Hyperthyroidism or severity of orbital disease does not affect the CCT.

Changes in intraocular pressure and corneal and retinal nerve fiber layer thicknesses in hypothyroidism.

PURPOSE: To evaluate the changes in intraocular pressure (IOP), corneal thickness (CT), and retinal nerve fiber layer thickness (RNFLT) in patients with hypothyroidism before and after treatment. METHODS: A complete ophthalmic examination including visual acuity, IOP, anterior segment, and fundus examination together with CT and RNFLT measurements were performed for each patient with newly diagnosed hypothyroidism, at the initial diagnosis and the third and ninth months of the L-thyroxine treatment. Wilcoxon signed rank test and Spearman's correlation test were used for statistical evaluation of the results. RESULTS: A total of 56 eyes of 28 patients were included in the study. The mean IOP and CT values were found to decrease with medical treatment (p = 0.000). There was no significant change in any of the RNFLT parameters measured with scanning laser polarimeter after L-thyroxine treatment (Wilcoxon, p > 0.05). The change in IOP levels was not correlated with the change in thyroid hormone levels (Spearman's correlation test, p > 0.05). The mean increase in serum free T3 and serum free T4 levels and the mean decrease in serum TSH levels at the ninth month of the therapy were found to be correlated with the decrease in CT in the left eyes (Spearman's correlation test, R > 0.4 and p < 0.05). CONCLUSIONS: Hypothyroidism seems to cause a reversible increase in CT and IOP. IOP changes may be secondary to CT changes. RNFLT parameters measured with scanning laser polarimeter do not seem to be affected by hypothyroidism. When the CT is taken into account and the IOPs corrected for CT, the prevalence of glaucoma in hypothyroidism may not be as high as previously reported. This issue should be taken into account while assessing glaucoma in patients with hypothyroidism.

Changes in intraocular pressure and corneal and retinal nerve fiber layer thicknesses in hypothyroidism.

PURPOSE: To evaluate the changes in intraocular pressure (IOP), corneal thickness (CT), and retinal nerve fiber layer thickness (RNFLT) in patients with hypothyroidism before and after treatment. METHODS: A complete ophthalmic examination including visual acuity, IOP, anterior segment, and fundus examination together with CT and RNFLT measurements were performed for each patient with newly diagnosed hypothyroidism, at the initial diagnosis and the third and ninth months of the L-thyroxine treatment. Wilcoxon signed rank test and Spearman's correlation test were used for statistical evaluation of the results. RESULTS: A total of 56 eyes of 28 patients were included in the study. The mean IOP and CT values were found to decrease with medical treatment (p=0.000). There was no significant change in any of the RNFLT parameters measured with scanning laser polarimeter after L-thyroxine treatment (Wilcoxon, p>0.05). The change in IOP levels was not correlated with the change in thyroid hormone levels (Spearman's correlation test, p>0.05). The mean increase in serum free T3 and serum free T4 levels and the mean decrease in serum TSH levels at the ninth month of the therapy were found to be correlated with the decrease in CT in the left eyes (Spearman's correlation test, R>0.4 and p<0.05). CONCLUSIONS: Hypothyroidism seems to cause a reversible increase in CT and IOP. IOP changes may be secondary to CT changes. RNFLT parameters measured with scanning laser polarimeter do not seem to be affected by hypothyroidism. When the CT is taken into account and the IOPs corrected for CT, the prevalence of glaucoma in hypothyroidism may not be as high as previously reported. This issue should be taken into account while assessing glaucoma in patients with hypothyroidism. (Eur J Ophthalmol 2005; 15: 556-61).

Assessment of retinal nerve fiber layer thickness with NFA-GDx following successful scleral buckling surgery.

PURPOSE: To assess the effect of retinal detachment (RD) on retinal nerve fiber layer (RNFL) thickness by using a scanning laser polarimeter (NFA-GDx) after successful scleral buckling surgery for the treatment of rhegmatogenous RD. METHODS: Consecutive patients who had successful scleral buckling surgery in one eye were assessed for RNFL thickness by using NFA-GDx prospectively. Fellow healthy eyes of the patients formed the control group. Eyes with RD surgery were compared with the control group with respect to three variables (superior average, inferior average, and average thickness) of NFA-GDx by using two-sampled t-test. Additionally, a possible effect of duration of RD on RNFL thickness was assessed with a correlation test. RESULTS: The study group consisted of 16 patients with a mean age of 49.8 years. The mean duration of RD was 28 days. Although the retardation values in operated eyes were less than that of the control eyes, the difference was not statistically significant (p > 0.05). However, these three values were seen to increase with increased duration of detachment and this correlation was statistically significant (R > 0.5, p < 0.03). CONCLUSIONS: RD seemed to cause minimal or no change in RNFL thickness as determined by GDx variables. The positive correlation between RNFL thickness and duration of RD, however, may be because of the proliferated Muller cells in eyes with RD, which may be responsible for some of the retardation measurements, which may be even more prominent in longstanding RD cases. This needs to be supported by further studies in larger patient groups with longer duration of RD and with histopathologic studies.

Assessment of nerve fiber layer in diabetic patients with scanning laser polarimetry.

OBJECTIVES: To evaluate the effects of diabetes mellitus, diabetic retinopathy and degree of blood glucose (BG) regulation on retinal nerve fiber layer (RNFL) thickness by using a scanning laser polarimeter (NFA-GDx). METHODS: We prospectively assessed RNFL thickness in four groups of patients, who were all age matched. Diabetic patients without diabetic retinopathy were grouped according to their BG regulation level into two, as: BG-regulated group (BG <140 mg/dl, HbA1c <8%, fructosamine <285 micromol/l, TG <200 mg/dl, n = 50), and BG-non-regulated group (BG = 140-250 mg/dl, HbA1c >8%, fructosamine >285 micromol/l, TG >200 mg/dl, n = 44). A group of patients with nonproliferative diabetic retinopathy (NPDR) formed the 3rd group (n = 41). The 4th group consisted of healthy subjects and acted as a control group (n = 50). Symmetry, superior maximum, ellipse modulation and the average thickness variables of NFA-GDx were used for the assessment. ANOVA test was used for the statistical analysis of variables between groups. RESULTS: The mean superior maximum and ellipse modulation values were statistically significantly lower than the control group in BG-non-regulated and NPDR groups (P < 0.05). The average thickness value was also statistically significantly lower than the control group in NPDR group. These values in the BG-regulated group were not statistically significantly different from the control group (P > 0.05). CONCLUSIONS: This is the first clinical study demonstrating the effects of diabetic glucose regulation level on RNFL by using NFA-GDx. RNFL thickness was seen to decrease with development of diabetic retinopathy and with impairment of metabolic regulation. This issue should be taken into account while assessing RNFL in diabetic glaucomatous patients.

Nerve fiber layer assessment with scanning laser polarimetry in glaucoma patients and glaucoma suspects.

PURPOSE: To investigate whether scanning laser polarimeter can differentiate glaucoma and suspected glaucoma patients from normals. METHODS: Polarimetric measurements were obtained using the nerve fiber analyzer (NFA)-I from 80 eyes of patients with glaucoma with mostly moderate glaucomatous optic nerve damage (37 eyes with primary open angle glaucoma, 21 with normal tension glaucoma, 17 with pseudoexfoliative glaucoma, 3 with angle closure glaucoma, and 2 with juvenile glaucoma), 53 eyes of patients suspected of glaucoma based on disc appearance, and from age-matched healthy volunteers as control groups. Ratios (superior/nasal, inferior/nasal, superior/inferior) were used for assessing nerve fiber layer (NFL) thickness. Student's t-test and linear regression analysis were used for statistical analysis. RESULTS: Both the glaucoma patients and glaucoma suspects had significantly lower NFL ratios (mean S/N 2.34 +/- 0.47, I/N 2.46 +/- 0.52, S/I 0.94 +/- 0.18) than the control groups (respectively 2.88 +/- 0.48, 2.88 +/- 0.48, 1.00 +/- 0.13) (p<0.05). There was an ample overlap between the patient groups and the normals. The superior and inferior NFL ratios in glaucoma patients gradually decreased as the mean defect in visual field increased (linear regression analysis, p<0.05). CONCLUSIONS: The NFL of glaucomatous eyes and eyes suspected of glaucoma based on disc appearance was significantly less thick than normals. NFA-I detects pathological abnormalities in some patients with glaucomatous optic nerve damage and normal visual fields as measured by conventional achromatic computerized perimetry. NFA-I, however, is unable to distinguish these patients from normals, at least using these parameters, because of the considerable overlap.

Pars plana lensectomy with double-capsule-supported intraocular lens implantation in children.

An alternative technique to manage pediatric cataracts comprises a pars plana lensectomy and anterior vitrectomy with anterior and posterior capsulotomies and posterior chamber heparin-surface-modified intraocular lens (IOL) implantation in the ciliary sulcus through a scleral tunnel. The surgical results in 7 eyes of 6 consecutive patients between 3.5 and 12.0 years old with developmental or traumatic cataract who had surgery using this technique were evaluated prospectively. Follow-up ranged from 12 to 19 months. All 7 eyes maintained a clear pupillary axis and a well-centered IOL from immediately after surgery to the last follow-up. Final best corrected visual acuity was 20/40 or better in 71% of cases.

Scanning laser polarimetry in normal subjects and patients with myopia.

AIMS: To examine the changes in the retinal nerve fibre layer (NFL) thickness with age and myopia in normal population. METHODS: Retinal nerve fibre layer thickness was measured with a scanning laser polarimeter (NFA-I) in 180 normal subjects of varying age (range 7-83 years) and in 110 eyes of 85 patients with myopia of varying degrees (range -1.00 to -15.00D). They were all voluntary Anatolian people. Superior to nasal (S/N), inferior to nasal (I/N), and the superior to inferior (S/I) ratios were used for the assessment of retinal NFL thickness. RESULTS: The mean superior NFL ratio was 2.96 and the mean inferior NFL ratio was 2.93 in normal subjects. There was a gradual decrease in NFL ratio with increasing age (simple regression analysis, p<0.05). The mean S/I ratio was 1.01 with a large variation. In patients with myopia, the mean superior NFL ratio was 2.60 and the mean inferior NFL ratio was 2.72. Superior and inferior NFL retardations, and S/I ratio in myopic patients were significantly (15.5%, 10.8%, and 4.9% respectively) lower than that of age matched normals (t test, p<0.05). There was also a gradual decrease in NFL thickness with increasing degree of myopia (simple regression analysis, p<0.05). CONCLUSIONS: Nomograms we obtained for retinal NFL thickness may serve as reference points for the assessment of normal Anatolian people and myopic patients in future studies. NFL thicknesses gradually decreased with increasing age. Patients with myopia had significantly lower NFL thicknesses than normal subjects and, although weakened by wide age range of myopic group, there is a linear relation between severity of myopia and NFL thickness in myopic patients.

Photorefractive keratectomy for visual rehabilitation of anisometropia induced by retinal detachment surgery.

PURPOSE: To evaluate the efficacy of unilateral photorefractive keratectomy to correct anisometropia induced by retinal detachment surgery. METHODS: Photorefractive keratectomy was performed in 10 eyes of 10 patients with anisometropia induced by previous retinal detachment surgery. The Aesculap Meditec MEL 60 excimer laser was used. RESULTS: Preoperative mean spherical equivalent refraction was -5.20 D. Mean postoperative spherical equivalent refraction was -0.25 D after a mean follow-up of 12.9 months. Mean preoperative spherical equivalent refraction difference between two eyes of 4.87 D was decreased to a mean 0.60 D postoperatively (t-test, P < .0001). All patients were free of anisometropic symptoms after laser surgery. CONCLUSION: Unilateral photorefractive keratectomy seems to be an effective method to correct anisometropia induced by conventional retinal detachment surgery, especially for patients with spectacle and contact lens intolerance.

Scanning laser polarimetry in corneal topographic changes after photorefractive keratectomy.

PURPOSE: To examine whether, or not, corneal topographic changes after excimer laser photorefractive keratectomy (PRK) for myopia and myopic astigmatism have any influence on measurements of the retinal nerve fiber layer (NFL) with scanning laser polarimetry. METHODS: Retinal NFL thicknesses were determined by scanning laser polarimetry in 17 eyes of 13 patients with myopia and myopic astigmatism before and after PRK. Total ablation depth ranged from 26 to 71 microm. We used the relative ratios for superior and inferior NFL thicknesses which were calculated by dividing the NFL values of respective regions by the nasal value. RESULTS: The mean superior NFL ratio measured was 3.02 +/- 0.92 preoperatively, and 3.00 +/- 0.76 postoperatively. The mean inferior NFL ratio was 2.95 +/- 0.75 preoperatively, and 2.99 +/- 0.66 postoperatively. There was no statistically significant difference between preoperative and postoperative NFL measurements (Wilcoxon signed rank test, p > 0.05). CONCLUSIONS: Corneal topographic changes after PRK have no significant influence on NFL measurements by scanning laser polarimetry. Our results suggest that scanning laser polarimetry can be used as a reliable method for retinal NFL thickness measurements even after excimer laser PRK.

The effect of EGb 761 on retinal lipid peroxidation and glutathione peroxidase level in experimental lens induced uveitis.

An acute lens-induced necrotizing intraocular inflammation was produced in pigmented guinea pigs. Treatment of these animals by 100 mg/kg/day EGb 761 a free oxygen radical scavenger for 10 days, reduced retinal lipid peroxidation (p > 0.05) and increased the retinal glutathione peroxidase level (p > 0.05). Although not significantly, these findings suggest that EGb 761 could be combined with other antiinflammatory drugs and may be beneficial in the treatment of uveitis.