Mehmet Ozgur Zengin

The effect of nicotine on choroidal thickness

Purpose To investigate the effect of nicotine on choroidal thickness using optical coherence tomography (OCT). Design Prospective, case–control study. Methods Sixteen young, healthy subjects and 16 age and gender matched control cases were included in this study; 4 mg nicotine gum was given to the study group and placebo gum to the control group. All participants underwent OCT scanning with a high-speed and resolution spectral-domain OCT device (3D OCT 2000, Topcon, Japan) at baseline, and 1 h following nicotine or placebo administration. The measurements were taken in the morning (10:00–12:00 hours) to avoid diurnal fluctuation. Results The median foveal choroidal thickness at baseline was 337.00 μm (IQR 84.50), which decreased to 311.00 μm (IQR 78.00) at 1 h following oral nicotine intake (p=0.001). The median choroidal thickness was also significantly decreased at five other extrafoveal points (p<0.05 for all). In the control group, the median baseline choroidal thickness at the fovea was 330.50 μm (IQR 104.25), and was 332.00 μm (IQR 103.75) at 1 h (p=0.271). Conclusions Nicotine causes a significant decrease in choroidal thickness following oral intake. This acute decrease might be a result of reduced ocular blood flow due to the vasoconstrictive effect of nicotine.

The Effect of ND:YAG Laser Posterior Capsulotomy Size on Refraction, Intraocular Pressure, and Macular Thickness.

Purpose. The aim of this study is to examine the influence of capsulotomy size on, spherical equivalent (SE), intraocular pressure (IOP), and macular thickness. Materials and Methods. Sixty-eight patients were examined preoperatively and 1, 4, and 12 weeks after Nd:YAG capsulotomy. Patients were divided into two groups based on the postoperative capsulotomy size. Changes in SE, IOP, and macular thickness were compared between two groups. Results. We found a higher hyperopic shift in large capsulotomy group. In both groups 1 and 2, IOP increased 1 week postoperatively. Intraocular pressure rise in group 2 was higher than in group 1. Both groups had increased macular thickness at 1 week postoperatively. The degree of macular thickening was similar in group 1 and group 2. Comment. Patients who underwent a larger capsulotomy have a higher hyperopic shift and IOP elevation. Rise in macular thickness was similar in large and small capsulotomy groups.

Retinal nerve fiber layer thickness changes in obstructive sleep apnea syndrome: one year follow-up results.

AIM To investigate the retinal nerve fiber layer (RNFL) thickness changes in patients with obstructive sleep apnea syndrome (OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography (3D-OCT-2000 Spectral domain). METHODS After polysomnographic study, all subjects (64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations, patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study. Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up 12mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index (AHI). RESULTS Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12(th) mo. Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects (P<0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness (P<0.05). CONCLUSION The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.

The return of the jedi: comparison of the outcomes of endolaser dacryocystorhinostomy and endonasal dacryocystorhinostomy

External dacryocystorhinostomy (DCR) is considered to be the gold standard treatment of primary acquired nasolacrimal duct obstruction. A better understanding of the endoscopic anatomy of the lacrimal sac has increased the success rate of endonasal DCR. Laser DCR has become popular in recent years and has a success rate comparable with those of other endonasal techniques. The aim of this study was to compare the surgical results of endonasal DCR (EDCR) and endonasal laser DCR (ELDCR).

Optic nerve and dura mater involvement as the first sign of multiple myeloma

Purpose To report a case of optic nerve and dura mater involvement as the first sign of multiple myeloma. Methods Case report. Results A 43-year-old woman presented with a headache and decreased vision in both eyes. Ophthalmic examination revealed anterior uveitis and subretinal mass around the optic nerves with accompanying disc edema bilaterally. Magnetic resonance imaging showed dural and optic nerve infiltration with tram-track enhancement in the optic nerve sheath. The diagnosis of multiple myeloma was made as a result of systemic investigations. The patient underwent systemic chemotherapy and cranial radiotherapy. After treatment, the patients headache disappeared, the papilledema regressed, and the ocular findings improved but complete recovery could not be achieved because of fibrous subretinal tissue and degenerative changes of the optic nerve. Conclusions Neurologic and ophthalmic involvement in multiple myeloma may appear as the first manifestation of disease. The correct diagnosis is important because it can be life-saving.

Correlation of intraocular pressure with central corneal thickness in premature and full-term newborns

Purpose To evaluate the relation of central corneal thickness (CCT) and intraocular pressure (IOP) in preterm and full-term newborns. Methods The study included preterm infants who were admitted to the neonatal intensive care unit. A group of consecutive full-term newborns served as control group. Linear and multiple regression analysis were carried out to assess the association of IOP with sex, gestational/postconceptional age, birthweight, mean oxygenation time, stages of retinopathy of prematurity (ROP), and CCT. Linear and multiple regression analysis were also carried out to assess the association of CCT with sex, gestational/postconceptional age, birthweight, mean oxygenation time, and stages of ROP. Results Mean IOP was 17.5 ± 2.1 mm Hg in premature newborns and 16.3 ± 1.9 mm Hg in full-term newborns (p = 0.001). Mean CCT was 576.5 ± 16.8 µm in premature newborns and 562.7 ± 18.5 mm in full-term newborns (p = 0.000). Intraocular pressure was not correlated with CCT in preterm infants. Intraocular pressure was moderately correlated with CCT in full-term infants. Sex, postconceptional age at birth and at measurement, age after birth at measurement, birthweight, mean oxygenation time, and stage of ROP were not related to IOP. Central corneal thickness was not correlated with any parameter. Conclusions Our results showed that the CCT does not affect IOP significantly in preterm infants. More prospective studies are needed for determining the effect of CCT and other ocular and systemic factors on IOP in preterm infants.

Changes in Choroidal Thickness in Patients With Obstructive Sleep Apnea Syndrome

BACKGROUND AND OBJECTIVE To evaluate choroidal thickness using spectral-domain optical coherence tomography (SD-OCT) in patients with obstructive sleep apnea syndrome (OSAS) in comparison to healthy controls. PATIENTS AND METHODS This observational, comparative study consisted of 35 patients with OSAS and 32 age- and sex-matched controls. The controls did not have systemic or ocular diseases. All study participants underwent complete ophthalmic examination as well as choroidal thickness measurement using a high-speed, high-resolution SD-OCT device. RESULTS The mean horizontal and vertical choroidal thicknesses, respectively, were 237.84 ± 69.9 μm and 234.97 ± 62.0 μm (P = .654) in patients with OSAS and 244.09 ± 41.2 μm and 241.88 ± 40.9 μm (P = .590) in the healthy controls. The mean choroidal thicknesses were thinner in patients with OSAS, but the difference was not significant (P > .05 for all values). CONCLUSION No differences in choroidal thickness were found between patients with OSAS and healthy controls.

Comparison of the Retinomax hand-held autorefractor versus table-top autorefractor and retinoscopy.

AIM To compare noncycloplegic and cycloplegic results of Retinomax measurements with findings achieved after cycloplegia using table-top autorefractor and retinoscopy. METHODS The study included 127 patients (mean age 96.7mo, range 21 to 221). Retinomax (Rmax) (Nikon Inc., Japan) was used to obtain noncycloplegic refraction. Under cycloplegia, refraction was measured with Rmax, table-top autorefractor (TTR) (Nikon NRK 8000, Inc., Japan) and retinoscopy. The values of sphere, spherical equivalent, cylinder and axis of cylinder were recorded for Rmax, TTR and retinoscopy in each eye. All results were analyzed statistically. RESULTS THE MEAN SPHERIC VALUES (SV), SPHERICAL EQUIVALENT VALUES (SEV) AND CYLINDRICAL VALUES (CV) OF THE NONCYCLOPLEGIC RMAX (SV: 0.64 D, SEV: 0.65 D and CV: 0.03 D, respectively) were found to be significantly lower than cycloplegic TTR (1.43 D, 1.38 D and 0.3 D; P=0.012, P=0.011 and P=0.04, respectively) and retinoscopy (1.34 D, 1.45 D and 0.23 D; P=0.04, P=0.002 and P=0.045, respectively). Mean cycloplegic SV, SEV, CV were not significantly different between Rmax and TTR, Rmax and retinoscopy, TTR and retinoscopy. Cycloplegic or noncycloplegic axis values were not different between any method. CONCLUSION Rmax may be used successfully as a screening tool but may not be accurate enough for actual spectacle prescription. Cycloplegic Rmax measurements may be able to identify refractive error in children because of approximate results to retinoscopy.

The effect of caffeine on choroidal thickness in young healthy subjects

Abstract Background: To investigate the effect of oral caffeine intake on choroidal thickness using optical coherence tomography (OCT). Methods: Eighteen otherwise healthy caffeine users and 18 controls were enrolled. All participants underwent OCT scanning with high-speed and resolution spectral-domain OCT device (3D OCT 2000, Topcon, Japan) at baseline, and 1 and 3 h following 200-mg oral caffeine intake in the study and after oral placebo in the control group. The measurements were taken in the morning (10–12 am) to avoid diurnal fluctuation. Results: The median choroidal thickness at the fovea prior to oral caffeine intake was 337.00 (IQR 83.75) μm, which decreased to 311.00 (IQR 79.25) μm at 1 h and 311.00 (IQR 75.00) μm at 3 h following oral caffeine intake (p = 0.001, 0.002, respectively). The median choroidal thickness was also significantly decreased following oral caffeine intake at other five extrafoveal points (p < 0.05 for all). The difference in choroidal thickness was not statistically significant between 1 and 3 h of caffeine intake at all six points. In the control group, the median baseline choroidal thickness at the fovea was 330.00 (IQR 88.75) μm, which was 330.50 (IQR 80.75) μm at 1 h and 330.50 (IQR 90.75) μm at 3 h (p = 0.552, 0.704, respectively). Conclusions: Caffeine causes a significant decrease in choroidal thickness following oral intake. This decrease might be a result of reduced ocular blood flow due to its vasoconstrictive effect.

The Evaluation of Choroidal Vascular Changes Associated with Vascular Dysregulation in Patients with Multiple Sclerosis Using Enhanced Depth Imaging Optical Coherence Tomography

Purpose: To evaluate the choroidal thickness (CT) in patients with Multiple Sclerosis (MS) using enhanced depth imaging optical coherence tomography (EDI-OCT) and comparing it with healthy subjects. Material/Methods: Sixty-four eyes of 32 patients with MS (22 women, 10 men, mean age: 37.5 ± 8.21 years) were enrolled in this study. Their choroidal thickness was measured using EDI-OCT, and compared with healthy subjects. CT was measured at fovea and at four extrafoveal points. Results: The mean subfoveal choroidal thickness was 327.01 ± 64.60 μm in MS patients and 365.3 ± 99.14 μm in controls ( p=0.019 ). Significant differences were found at points temporal 500 μm, temporal 1000 μm and nasal 500 μm to the fovea between patients and control group ( p=0.018, 0.003 and 0.03, respectively). Conclusions: Patients with MS had thinner choroids when compared to normal subjects. The decrease in mean choroidal thickness in MS patients compared to controls may be related to vascular dysregulation or inflammatory pathology of MS. Further prospective studies are needed to evaluate the choroidal thickness in MS patients.