Reproducibility, Repeatability, and Correlation of Central Corneal Thickness Measurement with the Pentacam Scheimpflug System and Ultrasound Pachymetry.

BACKGROUND/AIM: The importance of an accurate determination of central corneal thickness (CCT) relies on its diagnostic and therapeutic implications in glaucoma, corneal ectasias, corneal edema and endothelial function monitoring, and refractive surgery suitability, among others. We aimed to analyze the repeatability, reproducibility, correlation, and laterality variations of CCT measurements performed with the Pentacam HR and the standard of care ultrasound A-scan (USP). METHODS: A cross-sectional study including CCT measurements of healthy individuals was performed by three independent examiners with the Pentacam HR and USP. Intra-observer and inter-observer variations were calculated with intra-class correlation coefficients (ICCs). Bland-Altman plots and 95% limits of agreement (95% LoA) were used to assess the agreement between devices. Linear correlation was calculated with Pearson's coefficient. RESULTS: Thirty individuals (60 eyes), including 10 (33.3%) men and 20 (66.6%) women, with a mean age of 30.0 ± 9.1 years, were studied. No statistical differences were found in CCT measurements between Pentacam HR (range 500 - 609 µm) and USP (range 498 - 628 µm). There was a high degree of correlation in repeatability and reproducibility of each independent device (ICC > 0.90). Pearson's correlation between 1 vs. 2, 2 vs. 3, and 3 vs. 1 Pentacam HR attempts were 0.914, 0.958, and 0.925, respectively (p < 0.001). Corresponding results for USP were 0.957, 0.957, and 0.943 (p < 0.001). The Pentacam HR tended to overestimate CCT by a mean difference of 3.77 µm (95% LoA, - 24.9 - 18.4). Right eyes were also overestimated (- 3.6 ± 14.1 µm) with the Pentacam HR device, whereas left eyes were underestimated (1.3 ± 11.1 µm). CONCLUSIONS: The Pentacam HR device provides reliable operator-independent estimates of CCT. Right eyes exhibited a tendency to overestimate with the Pentacam HR. We suspect this difference is due to USP underestimation related to patients' position while performing the study. In clinically relevant scenarios, performing a third measurement and cautiously measuring right eyes can provide higher accuracy.

Estado de nutrición de yodo y prevalencia de concentraciones anormales de TSH en la población escolar de 6-7 años de la comunidad autónoma del País Vasco / Iodine nutrition status and prevalence of abnormal TSH levels in schoolchildren aged 6-7 years in the autonomous community of the Basque Country

Introducción: Un estudio epidemiológico realizado entre 1988 y 1992 puso de manifiesto la existencia de deficiencia de yodo y bocio endémico en la población escolar de la comunidad autónoma del País Vasco. Objetivos: 1) Conocer el estado de nutrición de yodo de los escolares de 6-7 años de edad y 2) estimar la prevalencia de concentraciones anormales de TSH en sangre capilar. Población y métodos: Fueron estudiados 497 escolares seleccionados mediante muestreo aleatorizado. Para evaluar el estado de nutrición de yodo se utilizó la mediana de las concentraciones urinarias de yodo (mCUY). Para estimar la prevalencia de concentraciones anormales de TSH se utilizó el intervalo de referencia derivado de la población estudiada. Resultados: La mCUY (P25-P75) fue de 140 μg/L (82-217). Fue mayor en los que utilizaban sal yodada en sus domicilios que en los que no lo hacían (146 [85-222] frente a 126 μg/L [73-198]; p < 0,05). También fue mayor en los que consumían 2 o más raciones diarias de leche y yogur que en los que consumían menos de 2 raciones (146 [87-225] vs. 110 μg/L [66-160]; p < 0,0001). La prevalencia de concentraciones anormales de TSH fue del 2%. No hubo correlación entre las concentraciones de TSH en sangre capilar y las CUY (R = 0,082; p = 0,076). Discusión y conclusiones: Los escolares de 6-7 años de la comunidad autónoma del País Vasco tienen un estado de nutrición de yodo adecuado. La utilización de sal yodada en el domicilio y el consumo diario de leche y yogur se asociaron con las mayores CUY

Introduction: An epidemiological study conducted between 1988 and 1992 showed iodine deficiency and endemic goiter in the schoolchildren of the autonomous community of the Basque Country. Objectives: 1) To ascertain the iodine nutrition status of schoolchildren aged 6-7 years, and 2) to estimate the prevalence of abnormal TSH levels in capillary blood. Population and methods: The study was conducted on 497 schoolchildren selected by random sampling. Median urinary iodine concentration (mUIC) was used to assess iodine nutritional status, and the reference interval derived from the study population was used to estimate the prevalence of abnormal TSH levels. Results: The mUIC (P25-P75) was 140 (82-217) μg/L. A higher value was found in those who used iodized salt at home than in those who did not (146 [85-222] versus 126 μg/L [73-198], P<0.05). It was also higher in those who consumed 2 or more daily servings of milk and yogurt than in those taking less than 2 servings (146 [87-225] versus 110 μg/L [66-160], P<0.0001). Abnormal TSH levels were found in 2% of children. There was no correlation between TSH levels in capillary blood and urinary iodine concentrations (R=0.082; P=0.076). Discussion and conclusions: Schoolchildren aged 6-7 years of the autonomous community of the Basque Country have an adequate iodine nutrition status. Use of iodized salt at home and daily consumption of milk and yogurt were associated to the highest UICs

Iodine nutrition status and prevalence of abnormal TSH levels in schoolchildren aged 6-7 years in the autonomous community of the Basque Country. / Estado de nutrición de yodo y prevalencia de concentraciones anormales de TSH en la población escolar de 6-7 años de la comunidad autónoma del País Vasco.

INTRODUCTION: An epidemiological study conducted between 1988 and 1992 showed iodine deficiency and endemic goiter in the schoolchildren of the autonomous community of the Basque Country. OBJECTIVES: 1) To ascertain the iodine nutrition status of schoolchildren aged 6-7 years, and 2) to estimate the prevalence of abnormal TSH levels in capillary blood. POPULATION AND METHODS: The study was conducted on 497 schoolchildren selected by random sampling. Median urinary iodine concentration (mUIC) was used to assess iodine nutritional status, and the reference interval derived from the study population was used to estimate the prevalence of abnormal TSH levels. RESULTS: The mUIC (P25-P75) was 140 (82-217) µg/L. A higher value was found in those who used iodized salt at home than in those who did not (146 [85-222] versus 126 µg/L [73-198], P<0.05). It was also higher in those who consumed 2 or more daily servings of milk and yogurt than in those taking less than 2 servings (146 [87-225] versus 110 µg/L [66-160], P<0.0001). Abnormal TSH levels were found in 2% of children. There was no correlation between TSH levels in capillary blood and urinary iodine concentrations (R=0.082; P=0.076). DISCUSSION AND CONCLUSIONS: Schoolchildren aged 6-7 years of the autonomous community of the Basque Country have an adequate iodine nutrition status. Use of iodized salt at home and daily consumption of milk and yogurt were associated to the highest UICs.

Iodine supplementation during pregnancy and lactation. Position statement of the working group on disorders related to iodine deficiency and thyroid dysfunction of the Spanish Society of Endocrinology and Nutrition.

Severe and mild iodine deficiency during pregnancy and lactation affects thyroid function of the mother and neonate as well as the infant's neuropsychological development. Studies performed in Spain confirm that most women are iodine deficient during pregnancy and lactation. Pregnant and breast feeding women and women planning to become pregnant should take iodine supplements.

Latino populations: a unique opportunity for the study of race, genetics, and social environment in epidemiological research.

Latinos are the largest minority population in the United States. Although usually classified as a single ethnic group by researchers, Latinos are heterogeneous from cultural, socioeconomic, and genetic perspectives. From a cultural and social perspective, Latinos represent a wide variety of national origins and ethnic and cultural groups, with a full spectrum of social class. From a genetic perspective, Latinos are descended from indigenous American, European, and African populations. We review the historical events that led to the formation of contemporary Latino populations and use results from recent genetic and clinical studies to illustrate the unique opportunity Latino groups offer for studying the interaction between racial, genetic, and environmental contributions to disease occurrence and drug response.