Transepithelial High-Intensity Cross-Linking for the Treatment of Progressive Keratoconus: 2-year Outcomes.

PURPOSE: To report 2-year outcomes of transepithelial high-intensity cross-linking (CXL) procedure in the treatment of patients with progressive keratoconus. METHODS: Forty-eight eyes of 48 consecutive progressive keratoconus patients who underwent transepithelial accelerated CXL procedure were enrolled in the study. Each patient underwent pre- and postoperative comprehensive ophthalmologic examinations including determination of refractive error as spherical equivalent (SE) and corrected distant visual acuity (CDVA), slit lamp biomicroscopic examination, fundoscopy, and a detailed analysis on a Scheimplug+Placido device (Sirius, CSO, Florence, Italy). The riboflavin solution, which was composed of riboflavin 0.25% with hydroxypropyl methylcellulose (HPMC) and benzalkonium chloride (BAC) (ParaCel, Avedro), was used in the procedure. The cornea was exposed to ultraviolet A light (KXL System, Avedro Inc., Waltham, MS, USA) for 2 minutes and 40 seconds at an irradiance of 45 mW/cm2. RESULTS: The mean age of the patients was 25.9 ± 4.0 (ranging from 18 to 33) years. No significant changes were observed in the mean CDVA, SE, and topographic indices at year 1 and year 2 visits compared to preoperative examination. The mean corneal thickness at the thinnest point was significantly higher at year 1 and year 2 visits than at preoperative examination (p1 = 0.014 and p2 = 0.017, respectively). No intra- or postoperative complications or adverse reactions were observed. CONCLUSIONS: Transepithelial high-intensity (irradiance of 45 mW/cm2 for 2 minutes and 40 seconds) CXL using 0.25% riboflavin solution was a safe and effective method to halt the progression of keratoconus for a 2-year follow-up period.

An Evaluation of Peripapillary Retinal Nerve Fiber Layer Thickness in Children With Epilepsy Receiving Treatment of Valproic Acid.

AIM: We investigated the peripapillary retinal nerve fiber layer thickness with optical coherence tomography in epileptic children receiving valproic acid monotherapy. MATERIALS AND METHODS: The study was conducted on children aged 8-16 years who were undergoing valproic acid monotherapy for epilepsy. The study group comprised a total of 40 children who met the inclusion criteria and 40 healthy age- and sex-matched children as a control group. Children with at least a 1-year history of epilepsy and taking 10-40 mg/kg/day treatment were included in the study. Peripapillary retinal nerve fiber layer thickness measurements were performed using Cirrus HD optical coherence tomography. All children and parents were informed about the study and informed consent was obtained from the parents of all the participants. RESULTS: The study group included 21 girls and 19 boys with a mean age of 10.6 ± 2.3 years. According to the results of optical coherence tomography measurements, the mean peripapillary retinal nerve fiber layer thickness was 91.6 ± 9.7 in the patient group and 95.5 ± 7.4 µm in the control group (P < 0.05). The superior peripapillary retinal nerve fiber layer thickness was 112.0 ± 13.2 in the patient group and 120.0 ± 14.7 µm in the control group (P < 0.02). According to the results of both measurements, the peripapillary retinal nerve fiber layer thickness was significantly lower in the patient group. Neither color vision loss nor visual field examination abnormality could be documented. CONCLUSION: According to the optical coherence tomography measurements, the average and superior peripapillary retinal nerve fiber layer thicknesses were thinner in patients with epilepsy who were receiving valproic acid monotherapy compared with healthy children. This situation can lead to undesirable results in terms of eye health. New studies are needed to investigate whether these findings are the result of epilepsy or can be attributed to valproic acid and whether there are adverse effects of valproic acid later in life.

Effect of inhaled fluticasone propionate on retinal nerve fiber layer thickness in asthmatic children.

PURPOSE: Corticosteroids are under suspicion of playing an important role in the development of retinopathy. We aimed to determine peripapillary retinal nerve fiber layer (RNFL) thinning by spectral-domain optical coherence tomography (OCT) in children being treated with inhaled fluticasone propionate due to asthma. METHODS: Thirty-eight children diagnosed with allergic asthma (mean age 9.8 ± 2.8 years, age range 6-13 years) and 40 age-similar controls were enrolled in this study. All children with asthma were taking inhaled fluticasone propionate at a dosage of 250 µg or more per day for at least 1 year. The RNFL thickness measurements were performed using Cirrus HD spectral-domain OCT 400. Central subfield thickness, cube average thickness, and cube volume were also measured. RESULTS: Among the 38 children with asthma and 40 healthy subjects who completed follow-up, children with asthma had similar mean peripapillary RNFL thicknesses compared with control children. The mean central subfield thickness was significantly higher than that of controls (248.8 ± 23.4 vs 237.5 ± 23.5, p<0.037). There was a positive linear relationship between cube average thickness and eosinophil count with a Pearson correlation coefficient of 0.336 (p<0.039) and a negative correlation was found between central subfield thickness and disease duration (r = -0.385, p = 0.017) in children with asthma. CONCLUSIONS: Asthmatic children have similar peripapillary RNFL measurements compared to controls on spectral-domain OCT. Raised eosinophil counts in asthmatic children were found to be significantly associated with cube average thickness.

The impact of hypertension on retinal nerve fiber layer thickness and its association with carotid intima media thickness.

OBJECTIVE: Our aim was to investigate retinal nerve fiber layer (RNFL) thickness in hypertensive patients using spectral-domain optical coherence tomography (SD-OCT) and to evaluate the relationship between RNFL thickness and carotid intima media thickness (CIMT). METHODS: This study included 59 patients with hypertension (HT) (53.6 ± 10.7 years) and 54 age-matched healthy controls (51.0 ± 8.1 years). We evaluated anthropometric and metabolic parameters as well as RNFL and CIMT measurements in patients with hypertension and controls. RESULTS: The average RNFL thickness was 86.60 ± 10.86 µm in hypertensive patients and 93.63 ± 7.30 µm in healthy controls (p < 0.001). Selective thinning of the RNFL was found in the superior and inferior quadrants. Mean CIMT values were higher in patients with HT (0.80 ± 0.15 mm) than the healthy subjects (0.71 ± 0.1 mm) (p < 0.001). The average, inferior and nasal RNFL thickness were negatively associated with diastolic blood pressure respectively (r = - 0.112, r = - 0.210, r = - 0.225). There was an inverse correlation between RNFL thickness in the average and superior retinal quadrant and CIMT (r = - 0.201, r = - 0.185). There were no correlations between RNFL thickness and age, body mass index, fasting plasma glucose, lipid parameters, high-sensitive C-reactive protein and microalbuminuria. CONCLUSION: RNFL thickness is reduced in hypertensive patients and may be associated with atherosclerosis.

Peripapillary retinal nerve fibre layer thickness in women with iron deficiency anaemia.

OBJECTIVE: To evaluate peripapillary retinal nerve fibre layer (RNFL) thickness in adult women with iron deficiency anaemia and healthy control subjects. METHODS: Women with iron deficiency anaemia and age- and sex-matched healthy control subjects were sequentially recruited and underwent detailed ophthalmic examination, including spectral-domain optical coherence tomography (OCT). Serum haemoglobin (Hb), iron and ferritin concentrations, total iron-binding capacity (TIBC) and mean corpuscular volume were determined. RESULTS: Peripapillary RNFL thicknesses in the nasal and inferior quadrants were significantly smaller in patients (n = 40) than in controls (n = 40). In the patient group, there were significant correlations between inferior quadrant RNFL thickness and Hb, and between nasal quadrant RNFL thickness and serum iron and ferritin concentrations, and TIBC. CONCLUSION: Iron deficiency anaemia reduces RNFL thickness in adult women.

Relationship between pinguecula formation and exposure to tandoor ovens in a hospital-based study.

AIM: To investigate the relationship between pinguecula and the use of tandoor ovens. METHODS: A total of 539 women, ranging in age from 20 to 86y who attended an outpatient clinic were enrolled. All the patients were asked whether they used tandoor ovens. Women exposed to tandoor ovens (n=286) were accepted as participants in the study group and they were compared with participants in the control group (n=253). The age, presence of pinguecula, duration of exposure to tandoor ovens as years and occupations were recorded for all the subjects. RESULTS: Mean duration for exposure to tandoor was 20.26y (range 1-62y) in the study group. The rate of pinguecula in the study group was 82.2% (235/286), and the rate in the control group was 37.5% (95/253); this difference was statistically significant (P<0.05). Pinguecula was seen in 61.2% (330/539) of all the participants. CONCLUSION: Pinguecula is strongly associated with exposure to tandoor ovens.

The relationship between retinal nerve fiber layer thickness and carotid intima media thickness in patients with type 2 diabetes mellitus.

AIMS: The aim of the present study was to investigate retinal nerve fiber layer (RNFL) thickness in patients with type 2 diabetes mellitus (T2D) using spectral-domain optical coherence tomography and to evaluate the relationship between RNFL thickness and carotid intima media thickness (CIMT). METHODS: This study included 171 patients with T2D (53.2 ± 8.8 years) and age matched 61 healthy controls (51.9 ± 8.1 years). We evaluated anthropometric and metabolic parameters as well as RNFL and CIMT measurements in patients with T2D and controls. The Mann-Whitney U test was used to compare the continuous variables and the Chi-square test was used to compare categorical variables. Spearman's rank correlation test was used for calculation of associations between variables. RESULTS: The average RNFL thickness was 84.82 ± 11.22 µm in patients with T2D and 92.35 ± 8.45 µm in healthy controls (p<0.001). Mean CIMT values were higher in patients with T2D (0.80 ± 0.1mm) than the healthy subjects (0.72 ± 0.1mm) (p<0.001). A significant negative correlation was found between age and all quadrants of RNFL. There was a negative correlation between average RNFL thickness and HbA1c (r=-0.176), uric acid (r=-0.145), CIMT (r=-0.190) and presence of carotid plaque (r=-0.193). The superior RNFL thickness was negatively associated with HbA1c (r=-0.175), CIMT (r=-0.207) and carotid plaque (r=-0.176). There was also an inverse correlation between the inferior RNFL thickness and HbA1c (r=-0.187) and carotid plaque (r=-0.157). CONCLUSION: Thinning of RNFL might be associated with atherosclerosis in patients with T2D.

Systemic arterial stiffness in patients with pseudoexfoliation glaucoma.

AIM: : To evaluate carotid-femoral pulse wave velocity (CF-PWV) values of patients with pseudoexfoliation (PEX) glaucoma in comparison with healthy subjects. METHODS: Twenty-five consecutive patients with PEX glaucoma (PEXG group) and 25 controls (control group) were included in the study. CF-PWV was assessed by a noninvasive device by the measurements of pulse transmit time and the distance between 2 recording sites. RESULTS: The mean age was 64.7±7.3 (range, 55 to 79) years the in PEXG group and 63.8±6.6 (range, 51 to 77) years in the control group. There were 8 men (32%) and 17 women (68%) in the PEXG group and 11 men (44%) and 14 women (56%) in the control group. The CF-PWV of the PEX group was significantly higher than that of the control group (P<0.001). CONCLUSIONS: We have revealed an association between PEXG and increased CF-PWV. Also, increased CF-PWV may be considered as a risk factor for the development of PEXG.

Effect of axial length on retinal nerve fiber layer thickness in children.

PURPOSE: To investigate the effect of axial length on peripapillary retinal nerve fiber layer (RNFL) thickness in myopic, hyperopic, and emmetropic eyes in children by Cirrus HD spectral-domain optical coherence tomography (OCT). METHODS: Subjects were divided into 3 groups according to their refractive status: myopic (n = 36), emmetropic (n = 30), and hyperopic (n = 28) eyes. The RNFL thickness measurements were taken from the superior, inferior, nasal, and temporal quadrants in the peripapillary region by Cirrus HD OCT. Axial length was also determined for each patient. RESULTS: The myopic eyes had thinner average RNFL and RNFLs of temporal, superior, nasal, and inferior quadrants than the hyperopic eyes (p1<0.001, p2 = 0.004, p3 = 0.011, p4 = 0.006, p5 = 0.033, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of all quadrants had significant negative correlations with axial length. On the other hand, after applying modified Littmann formula for correction of magnification effect, the differences among the 3 groups disappeared (all p>0.05). CONCLUSIONS: We have shown that axial length and accordingly refractive status influenced peripapillary RNFL thickness measurements by Cirrus HD OCT in children. Therefore, to make a correct diagnosis of glaucoma or other optic neuropathies in children, either axial length-induced magnification effect should be corrected by ophthalmologists or the current Cirrus HD OCT database should be revised taking axial length into consideration.

Investigation of tear osmolarity in early rheumatoid arthritis: relation to disease activity.

OBJECTIVE: To investigate the frequency of dry eye (DE) by measuring tear osmolarity (TO) with the recently introduced TearLab system (TearLab Corp, San Diego, Calif.) in patients with early rheumatoid arthritis (ERA) and the relationship between the severity of DE and ERA disease activity. DESIGN: Prospective study PARTICIPANTS: Sixty-four eyes of 64 newly diagnosed and untreated patients with ERA were enrolled in this study. METHODS: TO measurements, tear break-up time (TBUT), and Schirmer tests were performed. ERA disease activity was evaluated according to the disease activity score 28 (DAS28). The patients were divided into 3 groups according to DAS28 scores as follows: mild (DAS28 ≤ 3.2), moderate (3.2 < DAS28 ≤ 5.1), and severe (DAS28 > 5.1). RESULTS: DE was identified in 46 (71.8%) patients with ERA according to the TO values. There were significant differences among these groups concerning TO (p = 0.001) and TBUT (p = 0.005) scores, whereas there was no significant difference between these groups regarding Schirmer scores (p = 0.200). In addition, DAS28 values were positively correlated with TO values (r = 0.710, p < 0.001), negatively correlated with Schirmer scores, (r = -0.251, p = 0.045), and negatively correlated with TBUT scores (r = -0.335, p = 0.007) among all patients. CONCLUSIONS: Our study demonstrated a relationship between the ERA disease activity and severity of DE by using TO measurements with the TearLab system. Therefore, TO measurement could be added to other classical DE tests for diagnosing DE and for assessing the degree of disease activity of ERA.

Assessment of peripapillary retinal nerve fiber layer thickness in children with vitamin B12 deficiency.

PURPOSE: Vitamin B(12) deficiency is a worldwide problem. It affects all ages, including children. It is one of the most common nutritional disorders and can cause harmful effects on the nervous system. In this study, we compared the peripapillary retinal nerve fiber layer thickness (RNFLT) in a healthy control group with children with vitamin B(12) deficiency. In our study, we aimed to evaluate the effect of vitamin B(12) deficiency on the RNFLT in children with the optical coherence tomography (OCT) method. METHODS: Sixty-six children with a diagnosis of vitamin B(12) deficiency (patient group) and 66 age- and sex-matched healthy children (control group) were enrolled in this prospectively designed study. Blood counts, vitamin B(12) levels, folate levels, and full biochemical parameters were obtained for all the subjects in each group. Peripapillary RNFLT measurements were performed with Cirrus HD spectral domain OCT. RESULTS: The thickness of the superior retinal nerve fiber layer (RNFL) in the vitamin B(12) deficiency group was significantly lower than that of the control group (p = 0.037). Although the average thickness of the RNFL was lower in the patient group, there was no statistically significant differences (p = 0.216). In the vitamin B(12) deficiency group, the average RNFL thickness and the superior RNFL thickness were significantly correlated with vitamin B(12) levels ((r1) = 0.353, (p1) < 0.004 and (r2) = 0.416, (p2) = 0.001, respectively). CONCLUSION: Our study showed that a deficiency in vitamin B(12), elsewhere it is important for the development of the central nervous system, is associated with a reduction in the thickness of the superior RNFL.

Dry eye in patients with fibromyalgia and its relevance to functional and emotional status.

PURPOSE: To evaluate dry eye in patients with fibromyalgia (FM). METHODS: Fifty-three FM patients and 53 age and sex well-matched controls were included in this study. Visual analog scale (VAS), number of tender points, FM impact questionnaire (FIQ), Beck depression scale (BDS), Ocular Surface Disease Index (OSDI), the tear break-up time (TBUT), Schirmer test, and tear osmolarity (TO) were assessed. RESULTS: The OSDI, TBUT, Schirmer test, and TO scores of the FM and control groups were significantly different (P < 0.05). The OSDI, TBUT, Schirmer test, and TO were higher in FM with high FIQ, and TBUT and TO were higher in FM with high BDS. In FM patients, Schirmer test was correlated with the VAS (r = -0.429, P = 0.001), BDS (r = -0.277, P = 0.044), and FIQ (r = -0.382, P = 0.005), and the TBUT was correlated with the VAS (r = -0.537, P < 0.001), BDS (r = -0.350, P = 0.010), and FIQ (r = -0.456, P = 0.001). In addition, TO was significantly correlated with the VAS (r = 0.681, P < 0.001), BDS (r = 0.661, P < 0.001), and FIQ (r = 0.842, P < 0.001). However, no significant correlation existed between the OSDI and the VAS, BDS, or FIQ. CONCLUSIONS: We have revealed an association between FM disease activity and dry eye severity. The consideration of this relation will be useful in the treatment of FM with deteriorated clinical status.

Effect of pterygium surgery on tear osmolarity.

Purpose. To investigate changes of dry eye test results in patients who underwent pterygium surgery. Methods. Seventy-four patients who underwent primary pterygium surgery were enrolled in this study. At the baseline, 3-, 12-, and 18-month visits, measurements of tear osmolarity, BUT, and Schirmer test were performed. The patients were divided into 2 groups: Group 1, which consisted of patients in whom pterygium did not recur, and Group 2, which consisted of patients in whom pterygium recurred after surgery. Results. The patients in Group 1 had lower tear osmolarity levels after surgery than those at baseline (all P < 0.001). In Group 2 the tear osmolarity levels did not differ from baseline after 18 months (P = 0.057). The prevalence rates of dry eye syndrome (DES) were lower than that at baseline and 18 months after surgery in Group 1 (P = 0.002). In Group 2, the incidence of DES was lower after 3 months than at baseline (P = 0.03) but was similar to the baseline rate after 12 and 18 months (both P > 0.05). Conclusions. Anormal tear film function associated with pterygium. Pterygium excision improved tear osmolarity and tear film function. However, tear osmolarity deteriorated again with the recurrence of pterygium.

Retinal nerve fiber layer and ganglion cell layer thickness in patients receiving systemic isotretinoin therapy.

To evaluate the effect of oral isotretinoin therapy on retinal nerve fiber layer (RNFL) and ganglion cell layer (GCL) thickness by spectral domain optical coherence tomography (OCT). This prospective study included newly diagnosed nodulocystic acne patients about to receive isotretinoin treatment. Macular average GCL thickness and peripapillary average, temporal, nasal, inferior, and superior quadrant RNFL thickness were measured by OCT before and after isotretinoin treatment. Pre- and post-treatment measurements were compared with paired t test. Fifty-six eyes of 28 patients were included. The mean duration of the treatment was 6.5 ± 1.3 months. The mean average GCL thickness was 90.04 ± 5.87 (80-96) µm at baseline and 90.75 ± 6.34 (81-96) µm after treatment. The mean average RNFL thickness was 93.25 ± 6.06 µm (84-107) before treatment and 93.05 ± 5.54 µm (82-106) after treatment. There were no statistically significant differences between pre- and post-treatment values (all p > 0.05). A 6-month course of systemic isotretinoin therapy seems to have no unfavorable effect on retinal ganglion cells; however, larger studies with longer follow-up periods are needed to be conclusive.

Evaluation of peripapillary retinal nerve fiber layer thickness in patients with vitamin B12 deficiency using spectral domain optical coherence tomography.

PURPOSE: To compare peripapillary retinal nerve fiber layer (RNFL) thicknesses measured by Cirrus HD optical coherence tomography (OCT) of patients with vitamin B12 deficiency with healthy controls and to evaluate the correlation between the peripapillary RNFL thickness and plasma vitamin B12 levels. MATERIALS AND METHODS: Forty-five patients (19 male and 26 female) with a diagnosis of vitamin B12 deficiency (patient group) and 45 age- and sex- matched healthy subjects (control group) were consecutively enrolled in this study. Average, temporal, nasal, inferior, and superior quadrant peripapillary RNFL thicknesses of each subject were obtained using the Cirrus HD OCT. Disc area (DA) and rim area (RA), central subfield thickness (CST), cube volume (CV), and cube average thickness (CAT) were also measured. RESULTS: Mean age of each group was 33.1 ± 6.5 years (range: 21-45 years). Mean plasma vitamin B12 level was 114.8 ± 34.0 pg/mL in the patient group and was 405.1 ± 20.0 pg/mL in the control group (p < 0.001). The patient and control groups were similar regarding axial length, plasma folate levels, DA, RA, CST, CV, CAT, and RNFL thicknesses in superior, nasal, and inferior quadrants. However, average RNFL and RNFL in temporal quadrant were significantly thinner in the patient group than in the control group (p = 0.013 and p < 0.001, respectively). In addition, temporal (r = 0.356, p = 0.001) and average (r = 0.212, p = 0.045) peripapillary RNFL thicknesses were correlated with plasma vitamin B12 levels. CONCLUSION: We have shown that, as in other non-glaucomatous optic neuropathies, temporal quadrant RNFL thickness was thinner in patients with vitamin B12 deficiency and it was correlated with plasma vitamin B12 levels. Further studies are warranted to clarify the clinical relevance of these findings and the effects of vitamin B12 replacement therapy.

Peripapillary retinal nerve fiber layer thickness in children with iron deficiency anemia.

PURPOSE: To evaluate peripapillary retinal nerve fiber layer (RNFL) thickness in children with iron deficiency anemia (IDA) in comparison with healthy controls and to investigate the correlation between peripapillary RNFL thicknesses and the hematologic parameters in these subjects. METHODS: Forty eyes of 40 children with a diagnosis of IDA (anemic group) and 40 eyes of 40 age- and sex-matched healthy children (control group) were enrolled in this study. Peripapillary RNFL thickness measurements were performed using Cirrus HD optical coherence tomography (OCT). RESULTS: Mean age of each group was 11.3±2.7 years. Average RNFL and RNFLs of superior and inferior quadrants were significantly thinner in the anemic group than in the control group (p=0.006, p=0.005, and p=0.005, respectively). In addition, average peripapillary RNFL thickness and RNFL thicknesses of superior, inferior, and temporal quadrants were correlated with hemoglobin levels (r1=0.734, p1<0.001, r2=0.456, p2=0.005, r3=0.598, p3<0.001, r4=0.349, p4=0.037, respectively) in anemic group. CONCLUSIONS. We found that children with IDA had different peripapillary RNFL profile measured by Cirrus HD spectral-domain OCT. We caution ophthalmologists when they measure RNFL thickness in children to diagnose glaucoma or other neuro-ophthalmic disorders.

Retinal nerve fiber layer thickness in Parkinson disease.

Dopaminergic neuronal cells have been identified in the inner nuclear and inner plexiform layers of the human retina. The dopaminergic content of the retina is reduced in patients with idiopathic Parkinson disease (PD). These observations led us to study the retinal nerve fiber layer (RNFL) thickness in patients with PD without visual impairment compared to healthy controls using spectral-domain optical coherence tomography (SD-OCT). Eighty-two subjects, including 42 patients with PD, newly diagnosed and untreated (24 men, 18 women, age range: 47-66 years), and 40 healthy controls, were enrolled. Both eyes of patients with PD and controls were imaged with SD-OCT. The mean RNFL thickness was 77 ± 11.5 µm in PD patients and 89 ± 8.7 µm in healthy controls (P = 0.001). Selective thinning of the RNFL was found in the temporal region with mean temporal RNFL thickness of 66 ± 6.7 µm in PD patients and 75 ± 4.8 µm in controls (P = 0.001). The thickness of the RNFL is decreased in PD patients. Demonstrating progressive thinning of RNFL over time will be critical for validating optical coherence tomography as a viable biomarker of patients with PD.

Evaluation of the retinal changes in patients with chronic migraine.

The aim of this study was to investigate retinal nerve fiber layer (RNFL) thickness and macular changes (central subfield thickness, cube average thickness, cube volume) in patients with chronic migraine (CM) without visual impairment using spectral-domain optical coherence tomography (SD-OCT) and to compare the results to healthy controls. A total of 80 subjects, including 40 CM patients (24 females, 16 males, [corrected] at 19-36 years of age) with no migraine prophylactic treatment and 40 healthy controls (22 females, 18 males, [corrected] at 20-40 years of age) were enrolled. Both eyes of patients with CM and controls were imaged using Cirrus HD SD-OCT (Carl Zeiss Meditec, Dublin, CA, USA). The average RNFL thickness was not significantly thinner in patients with CM. The mean average RNFL thickness was 83 ± 10.5 µm in CM patients and 85 ± 9.6 µm in healthy controls (p = 0.648), but superior quadrant RNFL thickness in the CM patients was significantly lower than healthy controls. The mean superior RNFL thickness was 86 ± 6.7 µm in CM patients and 108 ± 7.3 µm in controls (p < 0.001). Illness duration and frequency of the attacks were not affected by RNFL thickness. No significant differences were detected in macular changes between CM patients and healthy controls. In our study, the thickness of superior RNFL was found to be thinner in CM patients. This implies that longitudinal follow-up is needed to clarify whether RNFL thinning, in migraine patients, is related to a progressive loss of axons and retinal ganglion cells.

Retinal nerve fiber layer thickness in patients with Alzheimer disease.

The aim of this study was to investigate retinal nerve fiber layer (RNFL) thickness in patients with Alzheimer disease (AD) without visual impairment using spectral domain optical coherence tomography (SD-OCT) and to compare the results with healthy controls. A total of 80 subjects, including 40 patients with early untreated AD (mean age, 69.3 ± 4.9 years) and 40 healthy controls (mean age, 68.9 ± 5.1 years) were enrolled. Both eyes of patients with AD and controls were imaged using SD-OCT. The average RNFL thickness was significantly less in the AD patients than in controls (65 ± 6.2 µm vs 75 ± 3.8µm; P = 0.001). There was selective thinning of the RNFL in the superior quadrant, the mean superior quadrant RNFL thickness being 76 ± 6.7 µm in AD patients and 105 ± 4.8 µm in controls (P = 0.001). In our study, the thickness of RNFL in patient with AD was lower than that of controls. This suggests that SD- OCT has the potential to be used in the early diagnosis of AD as well as in the study of therapeutic agents. Further studies are needed to validate this technology as a viable ocular biomarker over time in AD.