Normative values for optical coherence tomography parameters in healthy children and interexaminer agreement for choroidal thickness measurements.

PURPOSE: To (a) determine the normative values for optical coherence tomography (OCT) parameters such as central macular thickness, retinal nerve fiber layer thickness, and choroidal thickness in healthy children; (b) investigate the relationships of these parameters with axial length, central corneal thickness, refractive errors, and intraocular pressure; and (c) determine interexaminer agreement for choroidal thickness measurements. METHODS: In this cross-sectional study, 120 healthy children aged 8-15 years underwent detailed ophthalmological examination and OCT measurements. Choroidal thickness was measured at three separate locations by two independent examiners. RESULTS: The mean global retinal nerve fiber layer thickness was 98.75 ± 9.45 µm (79.0-121.0). The mean central macular thickness was 232.29 ± 29.37 µm (190.0-376.0). The mean subfoveal choroidal thickness obtained by examiner 1 was 344.38 ± 68.83 µm and that obtained by examiner 2 was 344.04 ± 68.92 µm. Interexaminer agreement was between 99.6%-99.8% for choroidal thickness at three separate locations. Central macular thickness increased with axial length (r=0.245, p=0.007). Choroidal thickness increased with age (r=0.291, p=0.001) and decreased with axial length (r=-0.191, p=0.037). Global retinal nerve fiber layer thickness decreased with axial length (r=-0.247, p=0.007) and increased with central corneal thickness (r=0.208, p=0.022). Global retinal nerve fiber layer thickness positively correlated with choroidal thickness (r=0.354, p<0.001). Global retinal nerve fiber layer thickness (r=0.223, p=0.014) and choroidal thickness (r=0.272, p=0.003) increased with the spherical equivalent (D). CONCLUSIONS: Optical coherence tomography parameters showed a wide range of variability in children. Retinal nerve fiber layer thickness, central macular thickness, and choroidal thickness were found to be either inter-related or correlated with age, central corneal thickness, axial length, and refractive errors. Furthermore, manual measurements of choroidal thickness showed high interexaminer agreement. Because normative values for optical coherence tomography parameters differed in children, the measurements should be interpreted according to an age-appropriate database.

Ocular surface alterations and in vivo confocal microscopic characteristics of corneas in patients with myasthenia gravis.

PURPOSE: To evaluate ocular surface alterations and characteristics of corneal basal epithelium and subbasal nerves in patients with myasthenia gravis. MATERIALS AND METHODS: Myasthenia gravis patients (n = 21) and healthy controls (n = 20) were enrolled. All participants underwent ocular surface testing in the following order: tear break-up time, lissamine green staining, Schirmer I test with anesthesia, and Ocular Surface Disease Index questionnaire. The Cochet-Bonnet esthesiometer was used to measure corneal sensitivity. Basal epithelial cells and subbasal nerves were evaluated using in vivo confocal microscopy. RESULTS: Myasthenia gravis patients had higher Ocular Surface Disease Index score (13.9 ± 15.0 vs 1.4 ± 2.2, p < 0.001) and lissamine green staining score (0.6 ± 0.4 vs 0.2 ± 0.4, p = 0.007). Break-up time score (9.3 ± 3.0 vs 9.9 ± 1.9, p = 0.481) and Schirmer I test score (16.5 ± 9.2 vs 19.3 ± 8.4, p = 0.323) did not differ significantly. Corneal sensation was 0.4 g/mm2 in all eyes. Patients with myasthenia gravis had lower basal epithelial cell density (3775.7 ± 938.1 vs 4983.1 ± 608.5, p < 0.001) and total nerve density (1956.1 ± 373.3 vs 2277.9 ± 405.0, p = 0.012) and higher subbasal nerve tortuosity (1.9 ± 0.8 vs 1.6 ± 0.7, p = 0.007) than controls. A significant increase in Ocular Surface Disease Index scores was found with decreasing basal epithelial cell density (rho = -0.518, p = 0.001). There was a significantly moderate negative correlation between the duration of myasthenia gravis and the number of corneal nerves (rho = -0.497, p = 0.022). CONCLUSION: Significant alterations of basal epithelial cells and subbasal nerves were demonstrated in myasthenia gravis patients although there was no difference of corneal sensitivity between myasthenia gravis patients and healthy controls. Thus, it should be borne in mind that myasthenia gravis patients deserve further evaluation with regard to ocular surface disease.

Ocular Surface Alterations in the Context of Corneal In Vivo Confocal Microscopic Characteristics in Patients With Fibromyalgia.

PURPOSE: To quantify the morphology of corneal basal epithelium and subbasal nerves and to evaluate the ocular surface alterations in patients with fibromyalgia (FM). METHODS: Patients with FM (n = 34) and healthy controls (n = 42) were enrolled. All participants underwent ocular surface tests in the following order: corneal sensitivity, tear film breakup time, lissamine green staining, Schirmer test, and the Ocular Surface Disease Index questionnaire. Basal epithelial cells and subbasal nerves were evaluated using in vivo confocal microscopy (IVCM). Demographic characteristics, Visual Analog Scale for Pain (VAS), American College of Rheumatology 1990, the Widespread Pain Index (WPI), and the Symptom Impact Questionnaire (SIQR) scores of patients with FM were obtained. RESULTS: Corneal sensitivity was 0.4 g/mm (fiber length: 6.0 cm) in all eyes. Patients with FM had a higher Ocular Surface Disease Index (42.2 ± 18.9 vs. 1.2 ± 1.7, P < 0.001), higher lissamine green staining scores (0.5 ± 0.5 vs. 0.05 ± 0.2, P < 0.001), and lower tear breakup time scores (9.0 ± 3.6 vs. 10.3 ± 1.5, P = 0.003) than the controls. Basal epithelial cell density (2709 ± 494 vs. 4491 ± 724), total nerve density (1563 ± 620 vs. 2545 ± 973), long nerve fibers (3.4 ± 1.3 vs. 4.5 ± 1.0), and the number of nerves (5.0 ± 1.8 vs. 10.3 ± 2.1) were all lower in patients with FM compared with those of the controls (P < 0.001 for all). There was a statistically significant negative correlation between the WPI score and Schirmer test results (rho = -0.374, P = 0.03) and between WPI and total nerve density (rho = -0.334, P = 0.054). CONCLUSIONS: To the best of our knowledge, this is the first study that evaluated ocular surface alterations in the context of corneal IVCM characteristics. Patients with FM should be evaluated in terms of ocular surface diseases. IVCM may be used in FM to assess small fiber neuropathy.

Normative values for optical coherence tomography parameters in healthy children and interexaminer agreement for choroidal thickness measurements / Valores normativos de parâmetros de tomografia de coerência óptica em crianças saudáveis e concordância interexaminador de medidas de espessura coroidal

ABSTRACT Purpose: To (a) determine the normative values for optical coherence tomography (OCT) parameters such as central macular thickness, retinal nerve fiber layer thickness, and choroidal thickness in healthy children; (b) investigate the relationships of these parameters with axial length, central corneal thickness, refractive errors, and intraocular pressure; and (c) determine interexaminer agreement for choroidal thickness measurements. Methods: In this cross-sectional study, 120 healthy children aged 8-15 years underwent detailed ophthalmological examination and OCT measurements. Choroidal thickness was measured at three separate locations by two independent examiners. Results: The mean global retinal nerve fiber layer thickness was 98.75 ± 9.45 μm (79.0-121.0). The mean central macular thickness was 232.29 ± 29.37 μm (190.0-376.0). The mean subfoveal choroidal thickness obtained by examiner 1 was 344.38 ± 68.83 μm and that obtained by examiner 2 was 344.04 ± 68.92 μm. Interexaminer agreement was between 99.6%-99.8% for choroidal thickness at three separate locations. Central macular thickness increased with axial length (r=0.245, p=0.007). Choroidal thickness increased with age (r=0.291, p=0.001) and decreased with axial length (r=-0.191, p=0.037). Global retinal nerve fiber layer thickness decreased with axial length (r=-0.247, p=0.007) and increased with central corneal thickness (r=0.208, p=0.022). Global retinal nerve fiber layer thickness positively correlated with choroidal thickness (r=0.354, p<0.001). Global retinal nerve fiber layer thickness (r=0.223, p=0.014) and choroidal thickness (r=0.272, p=0.003) increased with the spherical equivalent (D). Conclusions: Optical coherence tomography parameters showed a wide range of variability in children. Retinal nerve fiber layer thickness, central macular thickness, and choroidal thickness were found to be either inter-related or correlated with age, central corneal thickness, axial length, and refractive errors. Furthermore, manual measurements of choroidal thickness showed high interexaminer agreement. Because normative values for optical coherence tomography parameters differed in children, the measurements should be interpreted according to an age-appropriate database.

RESUMO Objetivo: Determinar valores normativos para parâmetros de tomografia de coerência óptica consistindo em espessura macular central, espessura da camada de fibra nervosa da retina e espessura coroidal em crianças saudáveis, para investigar suas relações com o comprimento axial, espessura corneana central, erros refractivos e pressão intraocular e determinar a concordância interexaminador para medidas de espessura coroidal. Métodos: um total de 120 crianças saudáveis com idade entre 8 e 15 anos foram submetidas a exame oftalmológico detalhado e a medições de tomografia de coerência óptica em uma configuração de estudo transversal. A espessura coroide foi medida por dois examinadores independentes em 3 pontos distintos. Resultados: A espessura global media da camada de fibra nervosa da retina foi de 98.75 ± 9.45 μm (79.0-121.0). A espessura macular central media foi de 232.29 ± 29.37 μm (190.0-376.0). A espessura coroidea subfoveal media foi de 344.38 ± 68.83 μm medida pelo examinador 1 e 344.04 ± 68.92 μm medida pelo examinador 2. A concordância foi entre 99.6-99.8% para a espessura coroidal em 3 pontos distintos. Verificou-se que a espessura macular central aumentava com o comprimento axial (r=0.245, p=0.007). A espessura da coroide aumentou com a idade (r=0.291, p=0.001) e diminuiu com o comprimento axial (r=-0.191, p=0.037). A espessura global da camada de fibras nervosas da retina diminuiu com o comprimento axial (r=-0.247, p=0.007) e aumenta com a espessura central da córnea (r=0.208, p=0.022). A espessura global da camada de fibras nervosas da retina foi correlacionada positivamente com a espessura coroidal (r=0.354, p<0.001). A espessura global da camada de fibras nervosas da retina (r=0.223, p=0.014) e a espessura coroide (r=0.272, p=0.003) aumentaram com o equivalente esférico (D). Conclusões: os parâmetros de tomografia de coerência óptica parecem mostrar uma ampla gama de variabilidade em crianças. A espessura da camada de fibra nervosa da retina, a espessura macular central, a espessura coroidea estão inter-relacionadas ou correlacionadas com a idade, espessura corneana central, comprimento axial e erros refractivos. Além disso, as medidas manuais da espessura coroidea apresentaram alta concordância entre examinadores. Deve-se ter em mente que os valores normativos dos parâmetros da tomografia de coerência óptica diferem em crianças, portanto, as medidas devem ser interpretadas de acordo com uma determinada base de dados apropriada para idade.