Berati Hasanreisoglu

Photorefractive keratectomy for post-penetrating keratoplasty myopia and astigmatism

Purpose: To determine the safety, effectiveness, and predictability of photorefractive keratectomy (PRK) for the correction of myopia and astigmatism after penetrating keratoplasty. Setting: Gazi University, Medical School, Department of Ophthalmology, Ankara, Turkey. Methods: Photorefractive keratectomy was performed in 16 eyes of 16 patients with postkeratoplasty myopia and astigmatism who were unable to wear glasses due to anisometropia and were contact lens intolerant. They were examined for uncorrected visual acuity (UCVA), best spectacle‐corrected visual acuity (BSCVA), and corneal transplant integrity before and after surgery. Results: The mean follow‐up after PRK was 26.0 months ± 15.7 (SD) (range 12 to 63 months). The mean preoperative spherical equivalent refraction of −4.47 ± 1.39 diopters (D) was −3.39 ± 1.84 D (P > .05) at the last postoperative visit and the mean preoperative cylinder of −5.62 ± 2.88 D was −3.23 ± 1.70 D (P < .05); refractive regression correlated with the amount of ablation performed. The BSCVA decreased in 3 eyes (18.8%), and the UCVA decreased in 2 (12.5%). Six eyes (37.5%) had grade 2 to 3 haze, which resolved spontaneously in 4 eyes within a relatively long time but caused a decrease in BSCVA in 2 (12.5%). Two of the eyes (12.5%) had a rejection episode after PRK and were successfully treated with topical steroids. Conclusions: Photorefractive keratectomy to correct postkeratoplasty myopia and astigmatism appears to be less effective and less predictable than PRK for naturally occurring myopia and astigmatism. Corneal haze and refractive regression are more prevalent, and patient satisfaction is not good.

Balanced orbital decompression combined with fat removal in Graves ophthalmopathy: do we really need to remove the third wall?

Purpose To compare the reduction of proptosis and the incidence of new-onset diplopia after 3-wall (medial, lateral, and inferior) orbital decompression versus balanced medial and lateral wall decompression combined with orbital fat excision in patients with Graves ophthalmopathy. Methods Three-wall orbital decompression including medial, inferior, and lateral walls was performed in 13 eyes of 7 patients (group 1), and balanced medial and lateral wall decompression combined with fat removal was performed in 18 eyes of 11 patients (group 2). A transnasal endoscopic approach was used for medial wall removal. A lateral canthotomy incision combined with a short upper eyelid incision was used for extended lateral wall removal, and this was combined with an inferior conjunctival fornix incision when floor decompression was performed. Results The mean reduction of proptosis was 6.9±1.6 mm and 6.5±1.3 mm in the first and second groups, respectively; the difference was not statistically significant (P =0.37). After 3-wall decompression, 57.1% of the patients had permanent new-onset diplopia (group 1), whereas none of the patients had permanent postoperative diplopia after balanced medial and lateral wall decompression combined with fat removal (group 2). The difference in permanent new-onset postoperative diplopia between two groups was statistically significant (P <0.001). Conclusions Balanced medial and lateral wall decompression combined with orbital fat removal provides an effective reduction in proptosis and reduces the incidence of postoperative permanent diplopia when compared with 3-wall decompression. This technique may eliminate the need for orbital floor excision.

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

Objective 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 μmol/l, TG <200 mg/dl, n = 50), and BG-non-regulated group (BG = 140–250 mg/dl, HbA1c >8%, fructosamine >285 μmol/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.

Optical Coherence Tomographic Assessment of Diabetic Macular Edema: Comparison with Fluorescein Angiographic and Clinical Findings

Purpose: To compare the optical coherence tomographic (OCT) features with clinical and fluorescein angiographic (FA) findings in patients with diabetic retinopathy. Methods: In a retrospective study ophthalmologic examination together with FA and OCT images were obtained from 195 eyes of 110 patients with different stages of diabetic retinopathy and OCT images were obtained from 40 eyes of 20 control subjects. Fluorescein leakage characteristics were organized into five groups: no leakage (1), focal (2), diffuse (3), combined focal + diffuse leakage (4) and cystoid (5). The Pearson correlation test was used to test the correlation between visual acuity and central foveal thickness and ANOVA was used for the statistical comparison between the groups. Results: The OCT images demonstrated retinal swelling in 66.1% of eyes, cystoid macular edema (CME) in 11.8% of eyes, serous foveal detachment + swelling in 6.2% of eyes, serous foveal detachment + swelling + CME in 3.6% of eyes and normal foveal structure in 12.3% of eyes. The best-corrected visual acuity was significantly correlated with central foveal thickness (r: –0.528, p < 0.01). There was 77% agreement between clinical examination and OCT results. CME was detected with OCT in 15.4% of eyes in our study, 40% of which was not detected with slit-lamp biomicroscopy and 63.3% of which was not evident in FA. None of the serous foveal detachments could be detected during slit-lamp biomicroscopy or FA. Conclusions: OCT-3 provided objective documentation of foveal structural changes in eyes with diabetic retinopathy. Best-corrected visual acuity provided a significant correlation with the retinal thickness at the central fovea. These results indicate that OCT can facilitate deciding on the treatment protocol (surgical or medical) and follow-up of diabetic patients, which is especially important in the early stages of diabetic maculopathy when the structural changes are not yet evident with slit-lamp biomicroscopy or angiographically.

Nonpenetrating glaucoma surgery: meta-analysis of recent results.

PurposeTo evaluate the efficacy of nonpenetrating glaucoma surgery for open angle glaucoma with respect to target intraocular pressure (IOP) and severity of glaucoma. Materials and MethodsA literature search with the terms “nonpenetrating glaucoma surgery, deep sclerectomy (DS), viscocanalostomy (VC), and open angle glaucoma” was carried out for the reports in the last 5 years. Studies encompassing only combined glaucoma and cataract surgery were excluded. Measurement of effectiveness was determined on the basis of achievement of target IOP. Data related to postoperative goniopuncture and needling with antimetabolite application were noted. ResultsThe percentage of cases achieving ≤21 mm Hg was 48.6% after primary DS, 68.7% after DS with implant, 67.1% after DS with antimetabolite, 51.1% after primary VC, and 36.8% after VC with antimetabolite or implant. Visual field parameters were almost exclusively not available; whereas cup/disk ratio and target IOP lower than 21 mm Hg were available in very few reports. With lower set IOP targets, the rates of success varied between 35% and 86% for DS, and between 10% and 67% for VC. The mean follow-up of the studies were mostly in the range of 3 years. ConclusionsNonpenetrating glaucoma surgery seems to provide IOP reduction into the high teens. Its potential to achieve lower target IOPs seems to be low. Longer-term studies, with data related to glaucoma severity and proper target IOPs are required.

Results of photorefractive keratectomy in keratoconus suspects at 4 years.

PURPOSE We studied the long-term results of photorefractive keratectomy (PRK) in keratoconus suspects detected by videokeratography (TMS). METHODS Bilateral inferior corneal steepening was detected in 6 candidates for PRK presenting with moderate myopia or astigmatism. Mean follow-up was 44.5 +/- 4.4 months (range, 38 to 54 mo). Mean spherical equivalent refraction was -5.18 +/- 1.60 D (mean sphere, -4.73 D; mean cyclinder, -0.92 D) which was stable for at least the preceding year. The quantitative measurement of inferior corneal steepening (I-S value) was greater than +1.60 (mean, 1.83 +/- 0.11) in all eyes. An Aesculap Meditec Mel 60 excimer laser was used for the PRK procedures and mean follow-up was 44.5 months. Postoperative pachymetric measurements were also performed in 6 eyes. RESULTS Postoperative uncorrected visual acuity was 20/20 in 8 eyes (66.6%) and 20/32 or better in all eyes with a mean postoperative spherical equivalent refraction of -0.70 +/- 0.74 D (mean sphere, -0.63 D; mean cyclinder, -0.39 D). Five eyes (41.6%) were within +/- 0.50 D spherical equivalent refraction. Inferior steepening was associated with thinning of the inferior cornea which was statistically significantly thinner than the superior thickness (Students t-test, P < .05). There were no wound healing problems or any sign that the excimer laser adversely affected the cornea during follow-up. CONCLUSIONS Photorefractive keratectomy seems to be a safe procedure for reducing or eliminating myopia or astigmatism in keratoconus suspect eyes-most probably forme fruste keratoconus-with a stable refraction, but this may be different in eyes with early keratoconus, known to be a progressive disease.

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 (ttest, 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.

Postoperative 5‐fluorouracil versus intraoperative mitomycin C in high‐risk glaucoma filtering surgery: extended follow up

Purpose: To compare the long‐term efficacy and safety of postoperative subconjunctival 5‐fluorouracil (5‐FU) injections with that of intraoperative mitomycin C (MMC) in eyes at high risk for failure of trabeculectomy.

Alterations in ocular surface and corneal thickness in relation to metabolic control in patients with chronic renal failure

Aim:  Ocular surface changes and ocular symptoms may be encountered in patients with chronic renal failure (CRF) undergoing haemodialysis. The ocular surface changes and its relationship with metabolic control in CRF patients were aimed to be emphasized in this study.

The effect of blood glucose regulation on retinal nerve fiber layer thickness in diabetic patients.

Purpose: To evaluate the effect of blood glucose (BG) regulation on the retinal nerve fiber layer (RNFL) in diabetic patients by using a scanning laser polarimeter (NFA-GDx). Methods: We prospectively assessed RNFL thickness in diabetic patients and an age-matched control group. Patients without diabetic retinopathy, with BG >250 mg/dl, HbA1c >8%, fructosamine >285 µmol/l and triglyceride >200 mg/dl were included in the study. RNFL assessment was performed before and after metabolic regulation of diabetes. Symmetry, superior maximum, ellipse modulation and the average thickness variables of NFA-GDx were used for the assessment. Mann-Whitney U and Wilcoxon tests were used for the statistical analysis. Results: A total of 40 diabetic patients were included in the study and a repeat RNFL examination could be performed in 22 of them following regulation of BG levels. None of the GDx variables were significantly different between pre- and postregulation measurements (p > 0.05, Wilcoxon test). The mean superior maximum, ellipse modulation and average thickness values of the diabetic group were significantly lower than the control group (p < 0.05, Mann-Whitney U-test). Conclusions: Poor metabolic control of diabetes mellitus adversely affects the thickness of RNFL and this effect does not seem to be acute since it was not reversed by short-term BG regulation. This issue needs to be kept in mind when assessing glaucomatous progress in diabetic patients.