[Dynamic changes of axial length, corneal refractive power, and refractive state after cataract surgery in infants].

Objective: To investigate the changes of axial length, corneal refractive power, and refractive state in infants with congenital cataract surgery. Methods: Retrospective cohort study. Medical records of 103 patients who underwent congenital cataract surgery in the Eye Hospital of Wenzhou Medical University Hangzhou Branch from January 1, 2015 to December 31, 2018 were reviewed. There were 61 boys and 42 girls in the study. The mean age at the surgery of 103 congenital cataract patients was (3.95±1.94) months. In patients receiving bilateral cataract surgery, only the left eye was selected for analysis. The patients were followed up for at least 1 year. The patients were divided into the groups of <4 months old and 4-12 months old according to the age at cataract surgery. The change in the axial length, corneal refractive power, and refractive state of each patient at 1 year after surgery was analyzed. Independent sample t-test, one way variance analysis and simple linear regression were used for statistical analysis. Results: There were 71 cases of bilateral cataract, including 33 in the group of <4 months old and 38 in the group of 4-12 months old, and 32 cases of unilateral cataract, including 17 in the group of <4 months old and 15 in the group of 4-12 months old. The change in the axial length of bilateral cataract children in the <4-month-old group was (2.46±1.33) mm at 1 year after surgery, which was greater than (1.52± 1.00) mm in the group of 4-12 months old (t=3.21; P<0.01). In the same surgery age group, there was no significant difference in the change of axial length among bilateral cataract eyes, unilateral cataract eyes and the contralateral eyes at 1 year after surgery (both P>0.05). One year after surgery, the axial length of the eyes in patients with bilateral cataract, the affected eyes and the fellow eyes in patients with unilateral cataract all was highly correlated with the logarithm of the actual age (r=0.68, 0.52, 0.73; all P<0.01). The corneal refractive power showed a decreased trend with the increase of age. The change in the corneal refractive power of the bilateral cataract children in the <4-month-old group at 1 year after surgery was (1.43±2.87) D, and in the group of 4-12 months old was (0.68±2.10) D, but the difference was not statistically significant (P>0.05). The chang in spherical equivalent of bilateral cataract children was (2.02±2.60) D in the <4-month-old group, greater than that in the group of 4-12 months old [(0.69±1.89) D; t=2.15; P<0.05]. The change of spherical equivalent one year after surgery in 4-12 months group, unilateral cataract eyes was significantly greater than that of bilateral cataract eyes [(2.05±0.95) D vs. (0.69±1.89) D; t=2.49; P<0.05]. The spherical equivalent of both bilateral and unilateral cataract children was highly correlated with the actual age (r=-0.51, -0.54; both P<0.01). Conclusions: The axial length is increased, the corneal refractive power is decreased, and the spherical equivalent is decreased at 1 year after surgery for congenital cataract in infants. The younger the age at cataract surgery, the greater the change in the axial length, myopia drift, and corneal refractive power. (Chin J Ophthalmol, 2021, 57: 34-40).

[Distribution of the anterior corneal astigmatism in over 140 000 patients with age-related cataract].

Objective: To analyze the distribution characteristics of the anterior corneal astigmatism in 140 000 cataract patients from 18 hospitals in China. Methods: Retrospective study. A total of 143 889 patients (143 889 right eyes) over the age of 40 years with age-related catarac were admitted to 18 Aier eye hospitals in China from July 2015 to October 2018. The average values of the three measurements of the magnitude of anterior corneal astigmatism, the meridian of corneal astigmatism, anterior chamber depth, corneal refractive power, and axial length measured by IOLMaster 500 were obtained. The data acquisition method of each sub-center was to collect and analyze the electronic case data in accordance with the inclusion and exclusion criteria, and to provide them for the sponsor Wuhan Aier Eye Hospital. Non-normal distribution data are presented as M (P25, P75). Mann-Whitney test, Kruskal-Wallis test, Chi-square test were used to analyze the distribution differences of the magnitude of corneal astigmatism and the meridian of corneal astigmatism in gender, age, anterior chamber depth, corneal refractive power and axial length. Results: Among the 143 889 patients, 84 319 were females and 59 570 were males, the median age was 72 (65, 78) years old, the median corneal astigmatism was 0.84 (0.51, 1.33) D; the corneal astigmatism was ≥0.75 D in 80 895 patients (56.22%) and was ≥1.00 D in 57 304 patients (39.83%). The median corneal astigmatism was 0.87 (0.53, 1.37) D in women and 0.82 (0.50, 1.29) D in men; with statistical difference (U=-14.891; P<0.05). The proportion of with-the-rule (WTR) astigmatism was 33.26% (28 046/84 319) for women and 34.26% (20 408/59 570) for men; The proportion of against-the-rule (ATR) astigmatism was 49.08% (41 385/84 319) for women and 46.91% (27 945/59 570) for men, with statistical difference (χ²=70.913; P<0.05). With the increase of age, the magnitude of corneal astigmatism first decreased from 0.94 (0.57, 1.48) D to 0.75 (0.46, 1.18) D, and then increased to 1.19 (0.74, 1.79) D, with statistical difference (H=1 263.438; P<0.05), and the change was at 61 to 70 years old. With the increase of age, the proportion of WTR astigmatism decreased from 77.50% (396/511) to 12.50% (3/24), the proportion of ATR astigmatism increased from 11.15% (57/511) to 79.07% (34/43), and the proportion of oblique astigmatism changed little from 17.02% (16/94) to 19.92% (245/1 230), the distribution difference was significant (χ²=10 174.496; P<0.05). As the anterior chamber became shallow, the magnitude of corneal astigmatism significantly increased from 0.82 (0.51, 1.31) D to 1.05 (0.61, 1.56) D, and the proportion of ATR astigmatism increased from 47.32% (60 207/127 227) to 51.69% (184/356) (H=409.961, χ²=120.995, both P<0.05). With the corneal refractive power rising, the magnitude of corneal astigmatism increased from 0.80 (0.49, 1.33) D to 0.95 (0.58, 1.53) D, the proportion of ATR astigmatism decreased from 52.84% (4 963/9 392) to 39.97% (9 023/22 577); the difference was significant (H=808.562, χ²=752.147, both P<0.05). When the axial length was>25.00 mm, the magnitude of corneal astigmatism was highest [1.04 (0.62, 1.65) D], and the proportion of ATR astigmatism was also highest [49.00% (10 964/22 376)]; the difference was significant (H=2 071.198, χ²=131.130, all P<0.05). Conclusions: The meridian of corneal astigmatism in middle-aged and elderly cataract patients is mainly ATR astigmatism. With the increasing of age, the magnitude of corneal astigmatism decreases first and then increases. The turning point from the proportion of WTR astigmatism to the proportion of ATR astigmatism is 65 years old. The shallower the anterior chamber is, the more the magnitude of corneal astigmatism and the proportion of ATR astigmatism increase. When the axial length is>25.00 mm, both the magnitude of corneal astigmatism and the proportion of ATR astigmatism reach the peak. (Chin J Ophthalmol, 2021, 57: 56-62).

[The rotational stability of Toric intraocular lenses and influencing factors in cataract patients with different axial length].

Objective: To evaluate the rotational stability of the Toric intraocular lens (TIOL) and influencing factors in cataract patients with different axial length. Methods: This retrospective cohort study consecutively enrolled patients who had phacoemulsification and AcrySof TIOL implantation in Peking University Third Hospital from May 2018 to January 2019. Based on axial length, patients were divided into two groups. Group A consisted of patients whose axial length was ≤ 24 mm. Patients whose axial length was >24 mm were included in group B. Data at three months postoperatively were used to evaluate the rotational stability of TIOL and its correlation with axial length, corneal white to white distance, lens thickness and TIOL spherical power. And t test, nonparametric test, chi-square test and Spearman test were used for statistical analysis. Results: Group A enrolled 39 patients (17 males and 22 females), with a median age of 74 years (range, 36-86 years). Group B enrolled 26 patients (11 males and 15 females), with a median age of 68 years (range, 36-86 years). For the efficacy of TIOL, in group A, the best corrected distance visual acuity (BCDVA, logarithm of the minimum angle of resolution) was 0.30 (0.10, 1.00) preoperatively and 0.10 (0.00, 0.60) postoperatively, and the astigmatism was 2.11 (0.95, 5.10) D preoperatively and 1.00 (0.00, 1.75) D postoperatively. In group B, the BCDVA was 0.36 (0.05, 1.00) preoperatively and 0.05 (0.00, 0.40) postoperatively, and the astigmatism was 2.00 (0.78, 3.76) D preoperatively and 0.75 (0.00, 2.25) D postoperatively. Between group A and group B, there were no significant differences in BCDVA (P=0.604) and astigmatism (P=0.789) preoperatively.In these two groups, postoperative BCDVA and astigmatism both significantly improved compared to preoperative parameters (both P<0.01). Between group A and group B, there were no significant differences in BCDVA (P=0.536) and astigmatism (P=0.076) postoperatively. In terms of rotational stability, the rotation in group A was 5.15°±3.62°, and that in group B was 6.50°±4.66°. There was no statistical difference between two groups (P=0.195). As for predictability, the percentage of eyes with rotation ≤5° was 59.0% (23 eyes) in group A and 50.0% (13 eyes) in group B. There was no statistical difference between the two groups (P=0.647). There was no significant correlation between the rotational stability of TIOL and axial length, corneal white to white distance, lens thickness or TIOL spherical power (P=0.836, 0.568, 0.170, 0.365). Conclusions: The rotational stability of TIOL at three months postoperatively in patients whose axial length >24 mm is of no difference with patients whose axial length ≤ 24 mm. It has no correlation with axial length, corneal white to white distance, lens thickness and TIOL spherical power. (Chin J Ophthalmol, 2020, 56: 41-46).

[Characteristics and analysis of corneal astigmatism in age-related cataract patients over 50 years old].

Objective: To investigate the relationship between corneal astigmatism and age, axial length (AL) in age-related cataract patients over 50 years old. Methods: In this retrospective study, 1 906 eyes of 953 patients with age-related cataract were diagnosed from February 2016 to August 2016 atPeking University People's Hospital, and their demographics, preoperative AL, magnitude and meridian of the corneal astigmatism measured by IOL Master were collected. Restricted cubic splines and Spearman rank correlation coefficients were used to investigate the relationship of the magnitude of cornea astigmatism to age. Chi-square test was used to assess the relationship of the meridian of astigmatism to age, AL and the magnitude of cornea astigmatism. Results: The patients were 410 men and 543 women. The corneal astigmatism was with-the-rule (WTR) in 570 eyes (29.91%), against-the-rule (ATR) in 1 005 eyes (52.73%) and oblique in 331 eyes (17.37%). The mean age was (72±9) years old. The medians (min, max) of AL and corneal astigmatism magnitude were 23.49 mm (19.83 mm to 33.89 mm) and 0.97 D (0.06 D to 4.65 D) in right eyes and 23.41 mm (17.54 mm to 32.09 mm) and 0.92 D (0.11 D to 4.88 D) in left eyes, respectively. The corneal astigmatism was ≥0.75 D in 64.95% (619/953) of the right eyes and 61.59% (587/953) of the left eyes. Among the elderly patients over 65 years old, when the AL was between 22.00-25.99 mm (r=0.186-0.279), the value of corneal astigmatism was positively correlated with age (all P<0.01) in both eyes. The value of ATR corneal astigmatism was positively correlated with age (right eyes, r=0.278, P<0.01; left eyes, r=0.225, P<0.01), while the value of WTR corneal astigmatism had no statistically significant correlation with age (right eyes, P=0.335; left eyes, P=0.633). The prevalence of WTR astigmatism decreased with age from 43.81% (46/105) to 20.73% (51/246) in right eyes and from 40.00% (42/105) to 24.80% (61/246) in left eyes, while the prevalence of ATR astigmatism increased with age from 38.10% (40/105) to 61.38% (151/246) in right eyes and from 33.33% (35/105) to 58.94% (145/246) in left eyes. The prevalence of oblique astigmatism was not significantly changed with age (right eyes, χ(2)=31.986, P<0.01; left eyes, χ(2)=27.686, P<0.01). There was no statistically significant difference in the distribution of corneal astigmatism meridians between different AL groups (right eyes, P=0.497; left eyes, P=0.897). With the increase of the magnitude of corneal astigmatism, the prevalence of oblique astigmatism significantly decreased from 25.45% (85/334) to 0 in right eyes and from 29.78% (109/366) to 1.35% (1/74) in left eyes, while the prevalence of ATR astigmatism significantly increased from 39.82% (133/334) to 79.27% (65/82) in right eyes and from 41.80% (153/366) to 59.46% (44/74) in left eyes (right eyes, χ(2)=72.229, P<0.01; left eyes, χ(2)=72.166, P<0.01). Conclusions: A majority of age-related cataract patients over 50 years old have astigmatism ≥0.75 D before cataract surgery. When the AL is between 22.00 mm and 25.99 mm, the magnitude of corneal astigmatism increases with age among people over 65 years old, especially the magnitude of ATR corneal astigmatism, while the magnitude of WTR corneal astigmatism has no obvious increase with age. The percentage of ATR astigmatism increases while the percentage of WTR astigmatism decreases with age. (Chin J Ophthalmol, 2020, 56: 349-355).

Comparison of three optical biometers: IOLMaster 500, Lenstar LS 900 and Aladdin.

PURPOSE: To evaluate the results of optical biometry using the IOLMaster 500, Lenstar LS 900 and Aladdin in eyes with cataract. METHODS: In 231 eyes of 152 patients with cataract, the measurements of 3 different biometers were retrospectively compared. Paired comparisons were performed for axial length (AL), mean keratometry (mean K) and anterior chamber depth (ACD). RESULTS: In only 197 of the 231 eyes (85.3%), it was possible to obtain reliable measurements of AL with all the three devices. It was not possible to determine AL in 16 eyes (6.9%) with Lenstar LS 900; in 19 eyes (8.2%) with Aladdin; and in 20 eyes (8.6%) with IOLMaster 500 possibly related to the severity of lens opacification (the corneas had good transparency in the eyes included in the study). There was a statistically significant difference in AL between IOLMaster 500 and the remaining two biometers (P = 0.03). However, the amount of difference was considered clinically not significant (0.04 mm). The mean keratometry (mean K) was determined in 203 eyes (87.9%) with all the three devices. Differences in mean K were between - 0.1 and 0.06 Diopters (D), which were considered neither statistically (P > 0.05) nor clinically significant. The anterior chamber depth (ACD) was determined in 197 eyes (85.28%) with all the three biometers. The differences between the three devices (0.03 to 0.13 mm) were not statistically significant and considered also clinically not significant. CONCLUSIONS: There were no clinically significant differences between these 3 biometers in AL, mean K and ACD.

[Recent studies on the signaling pathways implicated myopia].

Myopia has emerged as one of the major health issues in China given its increasingly high prevalence. It is generally accepted that myopia is the result of a complex interaction of environmental exposures and genetic predisposition. Many studies have indicated that abnormal visual stimulation regulates retinal neurotransmitters and growth factors to release resulting in scleral remodeling and axial elongation through signaling pathway transduction. It has been reported that the signaling pathways play important roles in the elongation of axial length and development of myopia. In this study, we reviewed several important signaling pathways implicated myopia.(Chin J Ophthalmol, 2019, 55:148-152).

[Comparison of biometry with the Pentacam AXL, IOLMaster 700 and IOLMaster 500 in cataract patients].

Objective: To compare biometry with new biometers of Pentacam AXL and IOLMaster 700 and the widely used biometer of IOLMaster 500 in cataract patients. Methods: Cross-sectional study. A total of 223 eyes of 147 cataract patients from Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University during 4-8 December 2017 were recruited. There were 67 males and 80 females with an age of (64±11) years.The axial length (AL), mean keratometry (Km), anterior chamber depth (ACD) and white-to-white corneal diameter (WTW) from each device were recorded. The difference and agreement between the measurements were evaluated by ANOVA, LSD test, intraclass correlation coefficient and Bland-Altman analysis. Results: The success rate of AL measurement was 85.2% (190/223) with the Pentacam AXL, 96.9% (216/223) with the IOLMaster 700 and 90.6% (202/223) with the IOLMaster 500. There was no difference among devices in measuring the AL, Km and ACD (all P>0.05). Significant difference was found in WTW [(11.36±0.42) vs. (11.69±0.45) vs. (11.45±0.42) mm; F=34.696, P=0.000]. Intraclass correlation coefficient was 0.859-1.000, and Bland-Altman analysis showed good agreement among three devices. Conclusions: The new biometers of Pentacam AXL and IOLMaster 700 and the widely used IOLMaster 500 show no difference in measuring AL, Km and ACD. All three devices show good agreement in biometry of cataract patients. (Chin J Ophthalmol, 2019, 55: 515-521).

[Choroidal thickness in preschool children].

Objective: To estimate the choroidal thickness (CT) in healthy children aged 2-6 years old and its relation to axial length, age and gender. Methods: Cross-sectional study. CT was assessed using spectral domain optical coherence tomography (OCT) in 126 children aged 2 to 6 years. CT was measured at nine locations, including the subfovea and 1 mm and 3 mm nasal, temporal, superior and inferior to the fovea. Results: Mean subfoveal choroidal thickness (SFCT) was 331.56±62.03 µm. The choroid was thickest at the subfoveal and 1 mm temporal area, and thinner nasally compared to temporally, superiorly and inferiorly. No statistical significance of SFCT between male and female was noted. Stepwise multiple regression analysis revealed that axial length and age were associated significantly with SFCT (P=0.00), while there was no detectable effect of sex on SFCT (P=0.94). Conclusions: Choroidal thickness was negatively correlated to axial length and positively correlated to age in preschool children. The development of the choroid in early childhood offset the effect of the expansion of eyes. Gender played a minor role in the choroidal development in early childhood. (Chin J Ophthalmol, 2019, 55:111-114).

[The heritability of phenotypes related to primary angle closure glaucoma].

Glaucoma is the leading cause of irreversible blindness throughout the world. Primary angle closure glaucoma (PACG) is one of the common types of this disease. Research indicates that its prevalence is always associated with many factors, including ocular anatomical characteristics and the genetic susceptibility. According to many studies, phenotypes related to PACG, such as anterior chamber depth, relative lens position and thickness, chamber angle state, and axial length, are heritable. Heritability is an important indicator to quantify this genetic tendency. Therefore, the study of heritability plays an important role in explaining the genetic susceptibility and understanding the mechanism of these diseases. This article reviews the heritability of the phenotypes that relate to PACG. (Chin J Ophthalmol, 2018, 54:864-867).

[Correlation between axial length and corneal curvature and spherical aberration].

Objective: To discuss the correlation between axial length and corneal curvature and corneal spherical aberration in a group of cataract patients with axial length greater than 24 mm. Methods: Retrospective case series. This study comprised 117 (234 eyes) age-related cataract patients. There were 51 men (43.59%) and 66 women (56.41%) with mean age of (69.0±8.7) years (range from 52.0 to 85.0 years). The average axial length was 27.6±1.8 (range from 24.2 to 31.9 mm). We devided them into four groups according to the axial length. A-scan was used to measure the axial length and Pentacam was used to get the corneal curvature and corneal spherical aberration of both anterior and posterior surface. kolmogorov-smirnov test was used to check the normal distribution. ANOVA test was used to compare eachcorneal parameter among different groups. Pearson correlation analysis was used to obtain the correlation of corneal parameters in groups. Results: There were correlations between the axial length and the anterior and posterior corneal curvature (r=-0.213, r=0.174, respectively, P<0.05). No correlation was found between the axial length and anterior or posterior corneal spherical aberration (r=-0.114, 0.055, respectively, P>0.05). Mean values of corneal anterior surface curvature were (45.26±1.60) D (group 1), (44.17±1.45) D (group 2), (44.40±1.99)D (group 3), and (44.53±1.69) D (group 4) respectively. Mean values of corneal posterior surface curvature were(-6.57±0.26)D (group 1), (-6.40±0.24)D (group 2), (-6.41±0.38)D (group 3), and (-6.43±0.26)D (group 4) respectively. There were significant difference of corneal anterior and posterior surface curvature among 4 groups (P=0.004, P=0.001). There was significant difference of corneal curvature of anterior surface in group 1 compared to group 2 and group 3(P<0.01, P=0.01). There was significant difference of curvature of posterior surface in group 1 compared to group 2 and group 3, respectively (P<0.01). Mean values of anterior surface corneal spherical aberration were (2.09±0.53) µm (group 1), (1.90±0.44) µm (group 2), (2.00±0.74) µm (group 3), and (1.78±0.52) µm (group 4) respectively. Mean values of posterior surface corneal spherical aberration were (2.69±1.15) µm (group 1), (2.46±1.16) µm (group 2), (2.92±2.51) µm (group 3), and (2.69±1.13) µm (group 4) respectively. No correlation was found in anterior and posterior surface corneal spherical aberration(P>0.05) among different groups. Conclusions: The eye with a longer axial length have a flatter cornea. Cornea fails to compensate for axial length elongation when the axial length is longer than 28mm. The corneal spherical aberration varies among individuals, which suggests us to do the customized measurement before cataract surgery to make a decision on choosing the aspherical intraocular lens. (Chin J Ophthalmol, 2017, 53: 255-259).

[Anterior corneal high-order aberrations in eyes with senile cataract in a Chinese population].

Objective: To investigate the distribution of anterior corneal high-order aberrations (HOAs) in Chinese eyes with cataract and their correlations with age and axial length for the choice of aspheric intraocular lens. Methods: Retrospective study. Six hundred twenty-five Chinese patients with cataract[male: 260, female: 365, age: (71.2±8.0) years] were categorized into 4 groups in accordance with their axial lengths. Anterior corneal HOAs in the central 6- mm zone was measured with an iTrace wavefront analyzer. The correlations between axial length, age and total HOAs, spherical aberration, trefoil aberration, and coma aberration were analyzed using Spearman analysis. The differences in total HOAs, spherical aberration, trefoil aberration, and coma aberration among 4 groups were assessed using the Krusal-Wallis H test. Results: Anterior corneal HOAs showed the nonnormal distribution. The median of corneal total HOAs was 0.666 µm (range 0.246 to 4.115 µm). Medians of coma aberration, spherical aberration and trefoil aberration were 0.313 µm (range 0.015 to 1.879 µm), 0.275 µm (range 0.005 to 1.797 µm) and 0.341 µm (range 0.019 to 2.319 µm), respectively. A significant negative correlation was found between axial length and total HOAs, coma aberration, spherical aberration, trefoil aberration (r=-0.230, -0.235, -0.143, -0.153, P<0.05). But no correlation was found between age and them (r=0.056, 0.045, 0.065, 0.022, P>0.05). Differences in total HOAs, coma aberration, spherical aberration, trefoil aberration were found among various axial groups (H=21.953, 20.665, 15.368, 16.881, P<0.05). Conclusions: Anterior corneal HOAs varied greatly among the majority of the patients. A significant negative correlation was found between axial length and anterior corneal HOAs, but no correlation was found between age and them. (Chin J Ophthalmol, 2017, 53: 828-834).

A new strategy to calculate the intraocular lens power in congenital cataracts according to age and axial length at implantation.

PURPOSE: The purpose of the study was to suggest a new method to calculate the intraocular lens (IOL) power in paediatric cataracts targeting emmetropia at the age of 15 years. METHODS: Data of children younger than 15 years who underwent cataract surgery with IOL implantation between 2005 and 2020 in the ophthalmological department of Marseille (South of France) was collected retrospectively. A logarithmic regression model was used to predict the axial length growth of the included eyes between implantation and 15 years. The predicted myopic shift served as target refraction to calculate a theoretical IOL power aiming for emmetropia at 15 years. Refractive error with the theoretical lens power was estimated as the spherical equivalent at the last follow-up minus the difference of target refractions between the implanted IOL and the theoretical one. Refractive errors using Dahan, Enyedi and Trivedi guidelines were also estimated and compared to the logarithmic model. RESULTS: Thirty-five eyes of 26 children were analysed. At the last follow-up, the median age of children was 10 years old and the median spherical equivalent was -1.88 dioptres (D) (IQR -3.81, -0.75). The estimated median refractive errors were 0.18 D (IQR -1.11, 1.42) with the logarithmic formula, -1.47 D (IQR -3.84, -0.65) with Dahan formula, -0.63 D (IQR -2.15, 0.32) with Enyedi formula and 0.38 D (IQR -1.58, 1.07) with Trivedi formula. CONCLUSION: The estimated refractive error with the new logarithmic formula is the closest to emmetropia at the last follow-up.

Intraocular lens power estimation for future emmetropia in pediatric cataract surgery / Estimativa do poder da lente intraocular para emetropia futura em cirurgias de catarata pediátrica

ABSTRACT Purpose: Creating models, in pediatric cataracts, to estimate kerotometry and axial length values at future ages, based on kerotometry and axial length measured at surgery, to estimate the intraocular lens power for emmetropia in future ages. Methods: Eyes with bilateral cataract and kerotometry and axial length measured at surgery and at least one postoperative examination with kerotometry and axial length measurements, were considered for this study. The models to estimate future kerotometry and axial length values were created considering (1) kerotometry and axial length measured at surgery, (2) the average slope of kerotometry and axial length logarithmic regression created for every single eye and (3) age at surgery. The intraocular lens for future ages can be estimated using these values in third generation formulas. The estimation errors for kerotometry, axial length and intraocular lens were also calculated. Results: A total of 57 eyes from 29 patients met the inclusion criteria. The average age at the surgery and follow-up was 36.96 ± 32.04 months and 2.39 ± 1.46 years, respectively. The average slope of logarithmic regression created for every single eye were -3.286 for kerotometry and +3.189 for axial length. The average absolute estimation errors for kerotometry and axial length were respectively: 0.61 ± 0.54 D and 0.49 ± 0.55 mm, and for intraocular lens using SRK-T, Hoffer-Q and Holladay I formulas were: 2 . 04 ± 1 . 73 D , 2 . 49 ± 2 . 10 D and 2 . 26 ± 1 . 87 D, respectively. Conclusions: The presented models could be used to estimate the intraocular lens power for emmetropia at future ages to guide the choice of the intraocular lens power to be implanted in pediatric cataract.

RESUMO Objetivo: Criar modelos, em catarata pediátrica, para estimar valores futuros de ceratometria e comprimento axial, com base na ceratometria e no comprimento axial medidos na cirurgia, para previsão do poder da lente intraocular para emetropia em idades futuras. Métodos: Olhos com catarata bilateral, ceratometria e comprimento axial medidos na cirurgia e pelo menos um exame pós-operatório com medidas de ceratometria e comprimento axial foram considerados para este estudo. Os modelos para estimar futuras ceratometrias e comprimentos axiais foram criados considerando (1) ceratometria e comprimento axial medidos na cirurgia, (2) a inclinação média da regressão logarítmica da ceratometria e comprimento axial criada para cada olho e (3) a idade na cirurgia. A lente intraocular para emetropia em idades futuras pode ser estimada usando esses valores em fórmulas de terceira geração. Os erros de estimativa da ceratometria, comprimento axial e poder da lente intraocular, usando os modelos, também foram calculados. Resultados: 57 olhos de 29 pacientes preencheram os critérios de inclusão. A idade média na cirurgia e acompanhamento foram de 36,96 ± 32,04 meses e 2,39 ± 1,46 anos, respectivamente. A inclinação média da regressão logarítmica criada para cada olho foi de -3.286 para ceratometria e + 3.189 para o comprimento axial. Os erros médios de estimativa absoluta para ceratometria e comprimento axial foram respectivamente: 0,61 ± 0,54 D e 0,49 ± 0,55 mm, e para o poder da lente intraocular usando as fórmulas SRK-T, Hoffer-Q e Holladay I foram: 2,04 ± 1,73 D, 2,49 ± 2,10 D e 2,26 ± 1,87 D, respectivamente. Conclusões: Os modelos apresentados podem ser utilizados para estimar o poder da lente intraocular que levaria a emetropia em idades futuras e orientar a escolha do poder da lente intraocular a ser implantada na catarata pediátrica.

Cataract Surgery with a New Fluidics Control Phacoemulsification System in Nanophthalmic Eyes.

PURPOSE: To report visual outcomes and complications after cataract surgery in nanophthalmic eyes with a phacoemulsification system using the active fluidics control strategy. METHODS: This is a retrospective case series. All eyes with an axial length of less than 20 mm that underwent cataract surgery or refractive lens exchange using the Centurion Vision System (Alcon Laboratories Inc.) in Hong Kong Sanatorium and Hospital were evaluated. The visual acuity and intraoperative and postoperative complications were reported. Prior approval from the Hospital Research Committee has been granted. RESULTS: Five eyes of 3 patients were included. The mean follow-up period was 10.2 ± 5.3 months (range, 4-18). Two eyes (40%) had a one-line loss of corrected distance visual acuity. No uveal effusion and posterior capsular tear developed. An optic crack and haptic breakage in the intraocular lens developed in 1 eye (20%) and 2 eyes (40%), respectively. Additional surgeries to treat high postoperative intraocular pressure were required in 1 eye (20%). CONCLUSION: The use of a new phacoemulsification system, which actively monitors and maintains the intraoperative pressure, facilitated anterior chamber stability during cataract surgery in nanophthalmic eyes. This minimized the risk of major complications related to unstable anterior chambers such as uveal effusion and posterior capsular tear. Development of intraoperative crack/breakage in a high-power intraocular lens was common.

Characterization of ocular biometric parameters in Colombian candidates for cataract surgery / Caracterización de los parámetros biométricos oculares de pacientes colombianos candidatos a cirugía de catarata

Abstract Introduction: Intraocular lens (IOL) power calculation, based on ocular biometry, is a determinant for the success of cataract surgery. Objectives: To characterize the ocular biometric parameters of Colombian patients over 40 years of age who are candidates for cataract surgery and to determine the prevalence of the 9 clinical conditions proposed by Holladay according to the interaction between axial length (AL) and anterior chamber depth (ACD). Materials and methods: Analytical cross-sectional study. The ocular biometry results of 781 patients (831 eyes) who were going to be taken to cataract surgery between January 2014 and January 2015 in Medellín, Colombia, were reviewed. After applying exclusion criteria, 716 eyes were included for analysis. Data on age, sex, AL, keratometry (flat keratometry (K1) and steep keratometry (K2)), ACD and white-to-white distance were collected. Results are presented using descriptive statistics. Results: Most eyes were from women (62.3%). The mean values of AL, K1 and ACD were 23.37±1.51mm, 43.52±2.06 and 3.03mm±0.41, respectively. Mean AL in men was 23.62±1.37mm, and in women, 23.21±1.67mm. The highest mean AL was observed in patients <50 years old (23.84±2.41) and the lowest in patients ≥80 years old (22.96±1.03 mm). Regarding eye size according to their AL, 90.5% were normal, 4.89% long, and 4.61% short. Conclusions: 85% of the participants had normal biometric parameters. For the remaining 15%, it is necessary to take some precautions when calculating IOL power, such as using fourth-generation formulas like Holladay 2 in long eyes, because the same refractive behavior will not be obtained using traditional prediction formulas in these patients. Furthermore, according to the Holladay classification, excluding normal eyes, the most frequent eyes were those with myopia and axial hyperopia.

Resumen Introducción. El cálculo del poder del lente intraocular (LIO), basado en la biometría ocular, es un factor determinante del éxito en la cirugía de catarata. Objetivos. Caracterizar los parámetros biométricos oculares de pacientes colombianos mayores de 40 años candidatos a cirugía de catarata y determinar la prevalencia de las 9 condiciones clínicas propuestas por Holladay según la interacción entre longitud axial (LA) y profundidad de la cámara anterior (ACD). Materiales y métodos. Estudio transversal analítico. Se revisaron los resultados de biometría ocular de 781 pacientes (831 ojos) que iban a ser sometidos a cirugía de cataratas entre enero de 2014 y enero de 2015 en Medellín, Colombia. Luego de aplicar los criterios de exclusión, se incluyeron 716 ojos para análisis. Se recolectaron datos sobre edad, sexo, LA, queratometría (queratometría más plana (K1), queratometría más curva (K2)), ACD y distancia blanco-blanco. Los resultados se presentan mediante estadística descriptiva. Resultados. La mayoría de ojos eran de mujeres (62.3%). Las medias de LA, K1 y ACD fueron 23.37±1.51mm, 43.52±2.06 y 3.03±0.41mm, respectivamente. La media de LA en hombres fue 23.62±1.37mm, y en mujeres, 23.21±1.67mm. La media más alta de LA se observó en pacientes <50 años (23.84±2.41mm) y la más baja en aquellos ≥80 años (22.96±1.03mm). Respecto al tamaño de los ojos según su LA, 90.5% fueron normales; 4.89%, largos, y 4.61%, cortos. Conclusiones. 85% de los participantes tuvo parámetros biométricos normales. Para el 15% restante es necesario tomar precauciones al calcular el poder del LIO, tales como el uso de fórmulas de cuarta generación como la Holladay 2 en ojos largos, pues en estos pacientes no se obtendrá el mismo comportamiento refractivo con las fórmulas de predicción tradicionales. Además, según la clasificación de Holladay, excluyendo a los ojos normales, los ojos más frecuentes fueron aquellos con miopía e hipermetropía axial.

The effects of pharmacological accommodation and cycloplegia on axial length and choroidal thickness / Efeitos da acomodação farmacológica e da cicloplegia no comprimento axial e na espessura da coroide

ABSTRACT Purpose: To investigate the effects of pharmacological accommodation and cycloplegia on ocular measurements. Methods: Thirty-three healthy subjects [mean (±SD) age, 32.97 (±5.21) years] volunteered to participate in the study. Measurement of the axial length, macular and choroidal thickness, refractive error, and corneal topography, as well as anterior segment imaging, were performed. After these procedures, pharmacological accommodation was induced by applying pilocarpine eye drops (pilocarpine hydrochloride 2%), and the measurements were repeated. The measurements were repeated again after full cycloplegia was induced using cyclopentolate eye drops (cyclopentolate hydrochloride 1%). The correlations between the measurements were evaluated. Results: A significant increase in subfoveal choroidal thickness after applying 2% pilocarpine was identified (without the drops, 319.36 ± 90.08 µm; with pilocarpine instillation, 341.60 ± 99.19 µm; with cyclopentolate instillation, 318.36 ± 103.0 µm; p<0.001). A significant increase in the axial length was also detected (without the drops, 23.26 ± 0.83 mm; with pilocarpine instillation, 23.29 ± 0.84 mm; with cyclopentolate instillation, 23.27 ± 0.84 mm; p=0.003). Comparing pharmacological accommodation and cycloplegia revealed a significant difference in central macular thickness (with pilocarpine instillation, 262.27 ± 19.34 µm; with cyclopentolate instillation, 265.93 ± 17.91 µm; p=0.016). Pilocarpine-related miosis (p<0.001) and myopic shift (p<0.001) were more severe in blue eyes vs. brown eyes. Conclusion: Pharmacological accommodation may change ocular measurements, such as choroidal thickness and axial length. This condition should be considered when performing ocular measurements, such as intraocular lens power calculations.(AU)

RESUMO Objetivo: Investigar os efeitos da acomodação farmacológica e da cicloplegia nas medições oculares. Métodos: participaram do estudo 33 voluntários saudáveis (média de idade [± DP], 32,97 anos [± 5,21 anos]). Foram medidos o comprimento axial, a espessura macular e coroidal e o erro refrativo, bem como realizados exames de imagem da topografia corneana e do segmento anterior. Em seguida, foi induzida a acomodação farmacológica aplicando-se colírio de pilocarpina (cloridrato de pilocarpina a 2%) e as medições foram repetidas nos participantes. As mesmas medições foram repetidas depois de induzir a cicloplegia completa com colírio de ciclopentolato (cloridrato de ciclopentolato a 1%) e foram avaliadas as correlações entre as medidas. Resultados: Identificou-se aumento significativo da espessura coroidal subfoveal com o uso da pilocarpina a 2% (sem colírio, 319,36 ± 90,08 µm; com a instilação de pilocarpina, 341,60 ± 99,19 µm; com a instilação de ciclopentolato, 318,36 ± 103,0 µm; p<0,001). Detectou-se também aumento significativo do comprimento axial (sem colírio, 23,26 ± 0,83 mm; com a instilação de pilocarpina, 23,29 ± 0,84 mm; com a instilação de ciclopentolato, 23,27 ± 0,84 mm; p=0,003). Ao se comparar a acomodação farmacológica e a cicloplegia, houve diferença significativa na espessura macular central (com a instilação de pilocarpina, 262,27 ± 19,34 µm; com a instilação de ciclopentolato, 265,93 ± 17,91 µm; p=0,016). Observou-se que a miose associada à pilocarpina (p<0,001) e o desvio miópico (p<0,001) foram mais severos nos olhos azuis que nos castanhos. Conclusão: A acomodação farmacológica pode alterar medidas oculares como a espessura da coroide e o comprimento axial. Essa possibilidade deve ser levada em consideração ao se efetuarem medições oculares, tais como cálculos de potência de lentes intraoculares.(AU)

Effects of axial length on retinal nerve fiber layer and macular ganglion cell-inner plexiform layer measured by spectral-domain OCT / Efeito do comprimento axial ocular na espessura da camada de fibras nervosas da retina e da camada de células ganglionares-plexiforme interna avaliadas por OCT espectral

ABSTRACT Purpose: To evaluate the influence of ocular axial length on circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness in healthy eyes after correcting for ocular magnification effect. Methods: In this cross-sectional study, we evaluated 120 eyes from 60 volunteer participants (myopes, emmetropes, and hyperopes). The thickness of the circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer were measured using the spectral optical coherence tomography (OCT)-Cirrus HD-OCT and correlated with ocular axial length. Adjustment for ocular magnification was performed by applying Littmann's formula. Results: Before the adjustment for ocular magnification, age-adjusted mixed models analysis demonstrated a significant negative correlation between axial length and average circumpapillary retinal nerve fiber layer thickness (r=-0.43, p<0.001), inferior circumpapillary retinal nerve fiber layer thickness (r=-0.46, p<0.001), superior circumpapillary retinal nerve fiber layer thickness (r=-0.31, p<0.05), nasal circumpapillary retinal nerve fiber layer thickness (r=-0.35, p<0.001), and average ganglion cell-inner plexiform layer thickness (r=-0.35, p<0.05). However, after correcting for magnification effect, the results were considerably different, revealing only a positive correlation between axial length and temporal retinal nerve fiber layer thickness (r=0.42, p<0.001). Additionally, we demonstrated a positive correlation between axial length and average ganglion cell-inner plexiform layer thickness (r=0.48, p<0.001). All other correlations were not found to be statistically significant. Conclusions: Before adjustment for ocular magnification, axial length was negatively correlated with circumpapillary retinal nerve fiber layer and ganglion cell-inner plexiform layer thickness measured by Cirrus-OCT. We attributed this effect to ocular magnification associated with greater axial lengths, which was corrected with the Littman's formula. Further studies are required to investigate the impact of ocular magnification correction on the diagnostic accuracy of Cirrus-OCT.

RESUMO Objetivo: Avaliar a influência do comprimento axial ocular na espessura da camada de fibras nervosas da retina peripapilar e na espessura da camada de células ganglionares-plexiforme interna em olhos saudáveis após correção para efeito de magnificação ocular. Métodos: Neste estudo transversal, avaliamos 120 olhos de 60 participantes voluntários (míopes, emétropes e hipermétropes). A espessura da camada de fibras nervosas da retina peripapilar e da camada de células ganglionares-plexiforme interna foram medidas usando a tomografia de coerência óptica espectral (OCT)-Cirrus HD-OCT e correlacionada com o comprimento axial ocular. O ajuste para a magnificação ocular foi realizado aplicando a fórmula de Littmann. Resultados: Antes do ajuste para magnificação ocular, a análise de modelos mistos ajustada por idade demonstrou uma correlação negativa significante entre o comprimento axial e a espessura média da camada de fibras nervosas da retina peripapilar (r=-0,43; p<0,001), espessura da camada de fibras nervosas da retina peripapilar inferior (r=-0,46; p <0,001), espessura da camada de fibras nervosas da retina peripapilar superior (r=-0,31; p<0,05), espessura da camada de fibras nervosas da retina peripapilar nasal (r=-0,35; p<0,001) e espessura média das células ganglionares-plexiforme interna (r=-0,35; p<0,05). No entanto, após a correção do efeito de magnificação, os resultados foram consideravelmente diferentes, revelando apenas uma correlação positiva entre o comprimento axial e a espessura temporal da camada de fibras nervosas da retina(r=0,42; p<0,001). Além disso, demonstramos uma correlação positiva entre o comprimento axial e a espessura média das células ganglionares-plexiforme interna (r=0,48; p<0,001). Todas as outras correlações não foram consideradas estatisticamente significativas. Conclusão: Antes do ajuste para o efeito de magnificação ocular, o comprimento axial estava negativamente correlacionado com a espessura da camada de fibras nervosas da retina peripapilar e das células ganglionares-plexiforme interna medido pelo Cirrus-OCT. Atribuimos esse efeito à magnificação ocular associada a comprimentos axiais maiores, o que foi corrigido com a fórmula de Littman. Mais estudos são necessários para investigaro impactoda correçãoda magnificação ocular na acurácia diagnóstica do Cirrus-OCT.

Optical biometry-based axial length alterations after intravitreal dexamethasone implant / Alterações do comprimento axial com base na biometria óptica após o implante de dexametasona intravítrea

ABSTRACT Purpose: To investigate changes in axial length after intravitreal dexamethasone implantation in patients with macular edema. Methods: We performed a prospective comparative study of 46 patients with unilateral macular edema, due to diabetic retinopathy, retinal vein occlusion, and non-infectious uveitis, who underwent dexamethasone implantation. The fellow eyes of the patients were considered the control group. The central macular thickness was measured by spectral-domain optical coherence tomography, and axial length was measured by IOLMaster 700 optical coherence biometry. We compared axial length and central macular thickness values within the groups. Results: In the study group, the baseline central macular thickness was 460.19 ± 128.64 mm, significantly decreasing to 324.00 ± 79.84 mm after dexamethasone implantation (p=0.000). No significant change in central macular thickness measurements was seen in the control group (p=0.244). In the study group, the baseline axial length was 23.16 ± 0.68 mm, significantly increasing to 23.22 ± 0.65 mm after dexamethasone implantation (p=0.039). However, the control group exhibited no significant change in axial length (p=0.123). Conclusions: In addition to significantly reducing central macular thickness measurements, intravitreal dexamethasone implantation also significantly changes optical biometry-based axial length measurements.

RESUMO Objetivo: Investigar alterações no comprimento axial após implante de dexametasona intravítrea em pacientes com edema macular. Métodos: Foi realizado um estudo prospectivo e comparativo de 46 pacientes com edema macular unilateral, devido à retinopatia diabética, oclusão da veia retiniana e uveíte não infecciosa, que foram submetidos ao implante de dexametasona. Os olhos contralateral de cada paciente foram considerados o grupo controle. A espessura macular central foi medida por tomografia de coerência óptica de domínio espectral, e o comprimento axial foi medido por meio de biometria de coerência óptica de domínio espectral e o comprimento axial foi medido pela biometria de coerência óptica com IOLMaster 700. Comparamos o comprimento axial e os valores da espessura macular central dentro dos grupos. Resultados: No grupo de estudo, a espessura macular basal foi de 460,19 ± 128,64 mm, diminuindo significativamente para 324,00 ± 79,84 mm após o implante de dexametasona (p=0,000). Nenhuma mudança significativa nas medidas da espessura macular central foi observada no grupo controle (p=0,244). No grupo de estudo, o comprimento axial basal foi de 23,16 ± 0,68 mm, aumentando significativamente para 23,22 ± 0,65 mm após o implante de dexametasona (p=0,039). No entanto, o grupo controle não apresentou alteração significativa no comprimento axial (p=0,123). Conclusões: Além de reduzir significativamente as medidas da espessura macular central, o implante de dexametasona intravítrea também altera significativamente as medidas de comprimento axial baseadas na biometria óptica.

Ângulos visuais: Artigo sobre a importância para o Implante de Lentes Intraoculares Multifocais / Visual angles: Article on the importance of Multifocal Intraocular Lenses Implantation

Resumo Objetivos: Medir o ângulo lâmbda (AL) em indivíduos no pré-operatório de facectomias, correlacionando a sua presença com o comprimento axial e o esférico dos olhos. Sugerir condutas para o implante de LIO multifocal de acordo com a presença do ângulo lâmbda. Métodos: Estudo transversal em 128 olhos de 74 indivíduos candidatos à cirurgia de catarata para registrar a equivalente presença do ângulo lâmbda. Resultados: Avaliando o ângulo lâmbda observou-se uma correlação positiva (r= 0,559 / p= 0,000) para o tamanho desse ângulo comparando-se os dois olhos. Não houve correlação entre o tamanho do ângulo lâmbda e o equivalente esférico no olho direito (r= -0,027 / p= 0,840), mas foi verificada correlação positiva para o olho esquerdo (r= 0,313 / p= 0,013). A presença da hipermetropia correlacionou com os comprimentos axiais pequenos, assim como a miopia com os grandes. Observou-se correlação negativa entre o tamanho do ângulo lâmbda e o comprimento axial para os dois olhos, sendo de r= -0,249 para o olho direito (p= 0,042) e r= -0,281 para o olho esquerdo (p= 0,018) Conclusões: Houve correlação entre a presença de ângulo lâmbda maior e comprimentos axiais menores para os dois olhos. Para o equivalente esférico hipermétrope houve correlação com a presença de um ângulo lâmbda maior apenas para o olho esquerdo. Esse trabalho sugere parcimônia nos implantes de LIO multifocal na presença de ângulo lâmbda significativo, baseado na teoria que a presença desse ângulo é reguladora do equilíbrio entre as aberrações da superfície corneana versus cristalineanas.

Abstract Objectives: To measure the labral angle (LA) in individuals in the preoperative period of facectomies, correlating their presence with axial length and spherical equivalent of the eyes. Suggest conduits for the implantation of multifocal IOL according to the presence of the lambda angle. Methods: A cross-sectional study of 128 eyes of 74 individuals who were candidates for cataract surgery to record the presence of the lambda angle. Results: A positive correlation (r = 0.559 / p = 0.000) was observed for the angle of this angle by comparing the two eyes. There was no correlation between the size of the lambda angle and the spherical equivalent in the right eye (r = -0.027 / p = 0.840), but a positive correlation was observed for the left eye (r = 0.313 / p = 0.013). The presence of hyperopia correlated with small axial lengths, as did myopia with large ones. There was a negative correlation between the angle of the tongue and the axial length of the two eyes, with r = -0.249 for the right eye (p = 0.042) and = 0.281 for the left eye (p = 0.018). Conclusions: There was a correlation between the presence of a larger lambda angle and smaller axial lengths for both eyes. For the spherical hypermétrope equivalent, there was a correlation with the presence of a larger blunt angle only for the left eye. This work suggests parsimony in multifocal IOL implants in the presence of a significant lamella angle, based on the theory that the presence of this angle regulates the balance between corneal versus crystaline surface aberrations.

Congenital and developmental cataract: axial length and keratometry study in Brazilian children / Catarata congênita e do desenvolvimento: estudo do comprimento axial e da ceratometria em crianças brasileiras

ABSTRACT Purpose: To evaluate the ocular axial length (AL) and keratometry (K) in Brazilian children with congenital/developmental cataract, assess the differences and evolution of AL and K according to age, and establish functional models of AL and K as function of age. Methods: Children with congenital/developmental cataract aged 1.5 months old to 8 years old and no other ocular diseases were included. All eyes with unilateral cataract, the left eyes from children with bilateral cataracts, and healthy eyes from children with unilateral cataract were analyzed. After the administration of anesthesia, K was measured with a portable automatic keratometer, and AL was measured with a contact biometer. Cataract surgery was performed immediately after the measurements were taken. The data were statistically analyzed, and a linear regression with an age logarithm was used to model the relationship. Results: Forty-four eyes with cataract were included in this analysis, comprising 15 eyes with unilateral cataract and 29 left eyes from children with bilateral cataracts. The mean age was 27.3 months with a mean AL of 20.63 ± 2.11 mm and a mean K of 44.94 ± 2.44 D. The K value was significantly steeper and the AL value was significantly shorter in younger children (P< 0.001). No significant differences were found neither between eyes with unilateral and bilateral cataracts nor between eyes with unilateral cataract and their corresponding healthy eyes (P >0.05). Conclusion: The values of K and AL significantly change with age, especially during the first 6 months of life. A linear functional relationship between K and AL with the logarithm of age and between K and AL was established.

RESUMO Objetivo: Avaliar o comprimento axial (AL) e a ceratometria (K) de olhos de crianças brasileiras com catarata congênita/desenvolvimento, analisar diferenças e evoluções de acordo com a idade e estabelecer modelos funcionais de comprimento axial e ceratometria em função da idade e entre eles. Métodos: Crianças com catarata congênita/desenvolvimento com idade de 1,5 meses a 8 anos de idade e sem outras doenças oculares foram incluídas. Todos os olhos com catarata unilateral, o olho esquerdo de crianças com catarata bilateral e o olho sadio de crianças com catarata unilateral foram analisados. Após a administração de anestesia, a ceratometria foi obtida com um ceratômetro automático portátil e o comprimento axial medido com um biômetro de contato. Em seguida, a cirurgia de catarata foi realizada. Os dados foram analisados estatisticamente, a regressão linear com o logaritmo da idade foi utilizado para modelar os relacionamentos. Resultados: Todos os olhos com catarata unilateral (n=15) e um olho selecionados aleatoriamente a partir dos casos bilaterais (n=29) foram incluídos na análise (total= 44 olhos). A idade média foi de 27,3 meses, as médias do comprimento axial e da ceratometria foram respectivamente 20,63 ± 2,11 mm e 44,94 ± 2,44 dioptrias. A ceratometria foi significativamente mais curvo e comprimento axial significantemente mais curto em crianças mais jovens (P<0,001). Não foram encontradas diferenças significativas na comparação entre os olhos com cataratas unilaterais e bilaterais e comparando os olhos com catarata unilateral a correspondentes olhos saudáveis (P>0,05). Conclusão: Os valores de ceratometria e comprimento axial mudam significativamente com a idade, principalmente nos primeiros seis meses de vida. Foi estabelecida uma relação funcional linear entre comprimento axial e ceratometria com o logaritmo da idade e entre ceratometria e comprimento axial.