Browsing by Author "Erkin, EF"
Now showing 1 - 11 of 11
Results Per Page
Sort Options
Item Unilateral refractive keratotomy for anisometropiaMaden, A; Erkin, EF; Oner, FHBACKGROUND: In anisometropia, the asymmetry of refractive error produces disparity of image magnification (aniseikonia) that can create visual discomfort, especially when asymmetry is 3.00 diopters or more. METHODS: A prospective study of 20 eyes of 20 patients between 18 and 61 years of age who underwent unilateral radial and/or transverse keratotomy was conducted; results of at least 12 months follow-up are presented. The efficacy of keratotomy was evaluated by the following criteria: 1) change in spherical and cylindrical refraction, 2) decrease in refraction difference between two eyes of each patient, 3) change in spectacle-corrected visual acuity, and 4) change in binocular vision functions and asthenopic complaints. RESULTS: Mean decrease in spherical refractive error was 3.66 +/- 1.58 D (range, 1.25 to 7.50 D) and 2.08 +/- 0.81 D (range, 1.00 to 3.50 D) in astigmatic refraction. The mean refraction difference between two eyes was 4.90 +/- 2.20 D preoperatively, and this difference regressed to 1.79 +/- 1.42 D postoperatively. Spectacle-corrected visual acuity increased in seven eyes (35%), remained the same in 12 eyes (60%) and decreased in one eye (5%). All patients reported relief of asthenopic complaints. Fusion amplitudes increased in 12 (60%) patients. Stereoscopic vision improved in five (25%) patients. CONCLUSION: Monocular refractive keratotomy can significantly decrease anisometropia.Item Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patientsErkin, EF; Çelik, P; Kayikçioglu, Ö; Deveci, HM; Sakar, AAims: To investigate the cardiovascular and respiratory effects of topical latanoprost 0.005% and topical betaxolol 0.25% monotherapy in newly diagnosed glaucoma patients. Methods: Forty newly diagnosed glaucoma patients were enrolled in this prospective, observer-masked, randomized, parallel study. Patients received either latanoprost 0.005% or betaxolol 0.25% for a duration of 3 months. Baseline evaluation included intraocular pressure (IOP) measurement and cardiorespiratory examinations including pulse rate, systolic and diastolic blood pressure measurements and spirometry. These measurements were repeated after 3 months. Results: Both latanoprost and betaxolol reduced IOP significantly (p = 0.001). After 3 months of therapy, the mean pulse rate, systolic and diastolic blood pressure values of the betaxolol group were reduced (p = 0.027, p = 0.07 and p = 0.016, respectively). No significant changes occurred in the cardiovascular measurements of the latanoprost group (p > 0.05). There were no significant changes in any of the spirometric measurements tested for both groups (p > 0.05). Conclusion: Both latanoprost and betaxolol are safe concerning respiratory functions. Betaxolol may cause small changes in the cardiovascular system, suggesting that blood pressure and pulse rates should be checked before and in regular intervals after prescribing it for the elderly. Latanoprost seems to be a safe medication in view of absence of systemic cardiovascular and respiratory side effects. Copyright (c) 2006 S. Karger AG, BaselItem Penetration of amikacin into aqueous humor of rabbitsErkin, EF; Günenç, Ü; Öner, FH; Gelal, A; Erkin, Y; Güven, HAmikacin is an aminoglycoside antibiotic that has poor corneal penetration due to its hydrophilic properties. The purpose of this study was to compare and evaluate the penetration of amikacin sulfate into aqueous humor of the rabbit eye when applied by different routes and concentrations, namely 100 or 250 mg/ml topical fortified amikacin eye drops, 100 or 250 mg/ml amikacin-embedded soft contact lenses and 25 mg subconjunctival amikacin injection. One hour after application, amikacin was not detectable in any of the 100 mg/ml concentration groups. High levels of amikacin above the minimum inhibitory concentration for susceptible bacteria were detected when applied subconjunctivally and by 250 mg/ mi topical fortified routes. Topical fortified amikacin 250 mg/ml reached the highest value in the aqueous (p < 0.05). Our results point out the poor corneal penetration of amikacin in standard concentrations from the intact rabbit cornea and that subconjunctival injections might provide satisfactory penetration. Copyright (C) 2001 S. Karger AG, Basel.Item The influence of religious fasting on basal tear secretion and tear break-up timeKayikçioglu, Ö; Erkin, EF; Erakgün, TMuslims abstain from food and drink from dawn to sunset during the holy month of Ramadan. An extended strict fasting may influence tear secretion and quality. We investigated changes in basal tear secretion (BTS) and tear break-up time (BUT) at the beginning and at the end of fasting on 32 healthy male patients with a mean age of 22.3 +/- 2.9 years. Body weight and urine specific gravity were also determined to assess the extent of dehydration due to fasting. Each case lost 0.1-1.25 kg of body weight while urine specific gravity changes were statistically insignificant. Mean BTS amount was 19.9 +/- 10.9 mm at the initial examination and 19.7 +/- 11.5 mm at the end of fasting (p=0.9). BUT values were 20.1 +/- 9.3 sec at the beginning of fasting and 23.5 +/- 14.9 sec at the end of fasting (p=0.19). We found that religious fasting in the winter season does not seem to affect BTS and BUT values in healthy individuals.Item Keratitis complicated by endophthalmitis 3 years after astigmatic keratotomyErkin, EF; Durak, I; Ferliel, S; Maden, AEndophthalmitis after keratotomy is rare and usually occurs soon after surgery. A 56-year-old woman with mild dry-eye symptoms developed keratitis complicated by endophthalmitis 3 years after astigmatic keratotomy (AK). The keratitis lasted for less than 1 day in the upper keratotomy incision. Corneal cultures yielded Pseudomonas aeruginosa. Keratitis progressed to endophthalmitis 1 day after the detection of keratitis. The inflammation was controlled with intravitreal, subconjunctival, topical, and systemic antibiotics. This case demonstrates the potential risk of endophthalmitis developing very shortly after late keratitis of AK incisions. Vigorous, early treatment and close follow-up seem justifiable in any keratitis associated with a keratotomy incision.Item Pattern reversal visual evoked potentials in different reproductive stages of femalesYilmaz, H; Mavioglu, H; Erkin, EF; Oksel, F; Lacin, SEstrogens increase after puberty and remain at high levels in the reproductive period and decrease with menopause. These changes occuring in the level of estrogens affect dopamine metabolism indirectly by causing changes in cathecholamine sensitivity of the brain. To assess the role of estrogens on the formation of pattern reversal evoked potentials (PRVEPs), three groups of patients were considered: prepubertal group, reproductive age group and postmenopausal group. PRVEPs of all subjects were recorded. Mean latency was shortest in the reproductive age. While no statistical difference was present between the mean latencies of prepubertal and the reproductive period groups, the mean latencies of both of these groups were statistically significantly shorter than that of the postmenopausal group(p<0.005).Item Trypan blue staining of the anterior capsule under an air bubble with a modified cannulaToprak, AB; Erkin, EF; Guler, CTo attain good visibility of the anterior capsule in the advanced or white cataract, trypan blue 0.1% is used to stain the anterior capsule. The dye is usually injected under an air bubble. However, it is difficult to inject the dye properly due to capillary forces. An ordinary anterior chamber cannula was modified and its coverage area increased to facilitate the staining of the anterior capsule under an air bubble. The anterior capsule was stained properly by using the modified cannula in all of the cases.Item Axial length measurement and asteroid hyalosisErkin, EF; Tarhan, S; Öztürk, FPurpose: To evaluate the effect of asteroid hyalosis on automated and manual A-scan axial length measurements. Setting: Celal Bayar University School of Medicine, Manisa, Turkey. Methods: A case-control study comprised 15 patients with unilateral asteroid hyalosis. The uninvolved eyes were used as controls. Axial length measurements by manual and automated A-scan biometry were performed in both eyes. The main outcome measures were comparisons between manual and automated measurements in asteroid hyalosis eyes with those in control eyes and the assessment of density of asteroid bodies on B-scan photographs. Results: Statistical analysis revealed no significant differences between axial lengths of asteroid hyalosis eyes and those in control eyes with automated (P = .524) or manual (P = .163) methods. Using automated biometry, 1 patient (7%) had a false (6.23 mm) short axial length measurement in the eye with asteroid hyalosis. There were no significant correlations between manual versus automated measurement differences and the density of the asteroid bodies. Conclusion: The axial length of the eye without asteroid hyalosis can be used to calculate intraocular lens power if the patient has no history of clinical anisometropia. (C) 1999 ASCRS and ESCRS.Item Visual evoked potentials in pregnancyYilmaz, H; Erkin, EF; Mavioglu, H; Sungurtekin, ÜPregnancy is a period when the estrogen/progesterone ratio rises considerably because of the passage of estrogen from the placenta. These changes in the level of estrogen during pregnancy increase the sensitivity of the central nervous system to cathecholamines. As a result, the sensitivity of the receptors in both the visual cortex and the inner plexiform layer of the retina to dopamine increases, and transmission in the optic pathways becomes faster. Inspired by this knowledge, we studied monocular pattern-reversal visual evoked potentials (PRVEPs) in both eyes of 30 pregnant women in the first trimester and 30 healthy nonpregnant women in the reproductive age. Mean P-100 latency of pregnant women was significantly shorter than mean P-100 latency of nonpregnant women (p<0.001). Mean P-100 amplitude values were higher in pregnant women, although not statistically significant (p>0.05). Plasma estrogen and progesterone levels of pregnant women showed a negative correlation with PRVEP latencies, but a positive correlation with PRVEP amplitudes. In conclusion, this study supports the impression that changes in the levels of sex steroids affect the formation of PRVEPs by their actions on the central nervous system. The increase in estrogen during pregnancy seems to facilitate neural transmission in the optic pathways. Rise in the estrogen-progesterone level might be responsible for the shorter PRVEPs latencies in pregnant women.Item Effects of betaxolol and latanoprost on ocular blood flow and visual fields in patients with primary open-angle glaucomaErkin, EF; Tarhan, S; Kayikçioglu, ÖR; Deveci, H; Güler, C; Göktan, CPURPOSE. To evaluate the effects of betaxolol and latanoprost on ocular blood flow and visual fields in patients with primary open-angle glaucoma (POAG) by means of an observer-masked, prospective clinical study. METHODS. Thirty-two patients with newly diagnosed POAG were included in the study. The patients were randomized into two groups. The first group was treated with betaxolol 0.50% twice daily and the second group with latanoprost 0.005% once daily. Baseline and posttreatment examinations on the first and third months of treatment included intraocularpressure (IOP) measurement, automated visual field testing, and ocular blood flow assessment. For evaluation of visual fields, mean defect and pattern standard deviation indices were used. Ocular blood flow was assessed by means of color Doppler imaging of the central retinal artery (CRA) and the temporal short posterior ciliary artery (PCA). For each vessel, peak systolic (PSV) and end-diastolic (EDV) blood flow velocities were measured and resistivity index (RI) calculated. RESULTS. After exclusion of one noncompliant patient, the study was completed with 31 eyes of 31 patients. Both drugs significantly reduced IOP (p<0.05). The mean IOP lowering effect of latanoprost was significantly higher than that of betaxolol (p=0.03). Visual field indices exhibited no significant changes in either group (p>0.05). There were no significant changes in PSV or EDV measurements of CRA or PCA in either group (p>0.05). RI decreased in both CRA and PCA with both drugs. The mean changes between baseline and 3 month blood flow measurements were not significantly different between betaxolol and latanoprost (p>0.05). CONCLUSIONS. Over a treatment period of 3 months, both betaxolol and latanoprost tended to improve ocular blood flow without one of them being superior to the other The results suggest that the direct (non IOP-dependent)influence on ocular circulation is better for betaxolol than for latanoprost. In addition, neither drug caused significant generalized improvements in visual fields during this period.Item Fluorescein dye disappearance test in patients with different degrees of epiphoraToprak, AB; Erkin, EF; Kayikçioglu, Ö; Seymenoglu, G; Güler, C; Unlu, HHPURPOSE. To assess the diagnostic efficacy of a modification of the fluorescein dye disappearance test (DDT) in patients with different degrees of epiphora. METHODS. DDT was performed by instilling a drop of 2% fluorescein in the eye. Schirmer tear test strips were placed in the lower conjunctival fornix, after 3 and 10 minutes. The colour dilution on the strips was compared to a scale with known standards and the most closely comparable colour dilution was chosen and recorded as the visual scale test (VST) grade of the strip. The grey-scale value (GV) of each strip was calculated by computer image analysis. The control group comprised 44 patients, mean age 44.8 years (SD 7.5, range 30-60). There were 13 patients in group 1 with moderate epiphora; mean age was 44.2 years (SD 9.5, range 30-60). There were 17 patients in group 2 with severe epiphora; mean age was 48.3 years (SD 7.7, range 37-60). RESULTS. VST and GV differed significantly between controls and group 1 patients at 3 minutes (p=0.002, p=0.001), and between controls and group 2 patients at 3 minutes (p<0.001, p<0.001). There was no difference between groups 1 and 2 patients in VST and GV at 3 minutes. The differences were highly significant between controls and group 1 at 10 minutes (p=0.001, p=0.007), and between controls and group 2 at 10 minutes (p<0.001, p<0.001). The differences in GV and VST between groups 1 and 2 were significant at 10 minutes (p=0.026, p=0.018). CONCLUSIONS. This modified DDT permits identification of different degrees of epiphora in a non-invasive manner, it can therefore be used to evaluate the outcome of different treatment strategies.