Corneal Evaluation in Healthy Brazilian Children Using a Scheimpflug Topography System

Abstract

Purpose: To identify the distribution and variation in corneal topography, thickness, and elevation in healthy Brazilian children as measured by the Pentacam Scheimpflug system (Oculus Optikgeräte GmbH, Wetzlar, Germany). Methods:Healthy children between 7 and 11 years of age were scanned using the Pentacam Scheimpflug corneal topography system (Oculus Optikgeräte GmbH, Wetzlar, Germany). The exclusion criteria were inability to undergo the ocular exam, history of any ocular diseases (including strabismus, amblyopia, cataracts, retinal disorders, and allergic conjunctivitis), and topographic diagnosis of corneal ectasia based on the modified Rabinowitz/McDonnell criteria for keratoconus. The right eye of each subject was selected for analysis. The parameters evaluated were central corneal thickness (CCT), thinnest pachymetry (TP), average pachymetric progression index (PPIave), anterior and posterior elevation (AE and PE), anterior and posterior best fit sphere (ABFS and PBFS), pachymetric difference between the apex and the thinnest point (PDAT), Ambrosio's relational thickness (ARTMax), overall Belin/Ambrósio Enhanced Ectasia display score (BAD-D), simulated keratometry (SimK), astigmatism in SimK (SimK astig), maximum keratometry (K max), asphericity (Q value), and anterior chamber depth (ACD).Results: A total of 160 children (69 male, 91 female) were included in this study. The mean age of the children was 8.82 ± 1.23 years (ranging from 7 to 11 years). The mean CCT was 553.81 ± 32 µm, and mean TP was 547.95 ± 32.06 µm. The TP was most commonly located in the inferotemporal quadrant in 93.125% (149) eyes. The mean PPIave was 1.00 ± 0.14, similar to that of normal adults. The mean ABFS and PBFS values were 7.49 ± 3.26 and 10.54 ± 6.25, respectively. ART Max and D averaged 446.57 ± 81.20 and 0.78 ± 0.65, respectively. Mean ± SD values for SimK, SimK astig, and K max were 43.35 ± 1.31 D, 0.92 ± 0.66 D, and 44.40 ± 1.45 D respectively. The K max and SimK astig values were close to those reported by other topographic systems for children. Q value and ACD averaged -0.39 ± 0.12 and 3.065 ± 0.2745 mm. Conclusion:This study provides normative values for corneal topography, thickness, and elevation in healthy Brazilian children. These results may provide helpful information for diagnosis of corneal diseases in children. Further studies are needed to evaluate the role of tomography in identifying early forms of ectasia in this age group.

The contact lens dry eyes questionnaire (CLDEQ-8) validation and ocular surface dysfunction among soft contact lens wearers

“…This additional analysis reached higher powers for all statistically significant variables (0.88 a 1.0). goals of the present study was to provide translation and validation of this questionnaire in Portuguese language, while following the standard procedures that are already well-defined in the literature (12,13,27) . Following this step, an important tool to screen and follow-up contact lens wearers is now available for incorporation in the clinical practices and researches in countries where Portuguese is the native language.…”

Corneal Scheimpflug topography values to distinguish between normal eyes, ocular allergy, and keratoconus in children

“…Previous studies have provided substantial information and many normative values for corneal power, astigmatism, corneal thickness, and pachymetric progression indices in adults and healthy children 13 . However, such parameters have not been studied in children with keratoconus or ocular allergy using current tomographers, such as the OCULUS Pentacam Scheimpflug topography system.…”

“…Further clinical and technological advances have produced a variety of indices that allow physicians to quantify the severity of corneal irregularity 10 , 11 . Despite the vast amount of studies evaluating corneal parameters in adults 12 and healthy children 13 , similar data on children with corneal irregularities are still scarce 14 . The lack of such information may limit the use of the Scheimpflug technology to identify abnormal corneas earlier in the disease’s progression.…”

Corneal Fourier and Belin–Ambrósio Enhanced Ectasia Analysis in Healthy 4-Year-Old White Children

“…25 Studies that presented normative values of healthy school children using the BAD in Brazil displayed a significant similarity in the main indices. 26,27 In children aged 9.72 ± 0.66 years, BAD D 0.78 ± 0.65, ART max 446.57 ± 81.20, and PPI avg 1.00 ± 0.14 were recorded, 26 while in 7–11-year-old children BAD D 0.80 ± 0.61, ART max 446.42 ± 75.23, and PPI avg 1.00 ± 0.13 were obtained. 27 Normative tomographic values in preschool children were presented by Hashem et al, but for the group of 3–6-year-old and the number of examinees was only 17.…”

“…25 Studies that presented normative values of healthy school children using the BAD in Brazil displayed a significant similarity in the main indices. 26,27 In children aged 9.72 6 0.66 years, BAD D 0.78 6 0.65, ART max 446.57 6 81.20, and PPI avg 1.00 6 0.14 were recorded, 26 while in 7-11-year-old children BAD D 0.80 6 0.61, ART max 446.42 6 75.23, and PPI avg 1.00 6 0.13 were K1, the flattest radius of curvature of the cornea, D; K2, the steepest radius of curvature of the cornea, D; Kmax, point of the highest breaking strength (D); PTL, thickness of the thinnest location on the cornea (pachymetry thinnest location, mm); DATL, distance from the apex of the cornea to the thinnest location on the cornea (distance apex-thinnest location, mm); F. Ele. Th., elevation values for the thinnest point on the cornea for the front surface of the cornea in relation to the reference best-fit sphere (BFS) (mm); B. Ele.…”