Refractive predictive errors using Barrett II, Hoffer-Q, and SRKT formulae for pediatric IOL implantation.

PURPOSE: To compare the accuracy of the Barrett II universal (BU II) formula, Hoffer-Q, and SRKT formulae following lensectomy and IOL implantation in a large pediatric cohort. METHODS: Retrospective study of children who underwent lensectomy and IOL implantation between 2015 and 2023 at Hadassah-Hebrew University Medical Center, Jerusalem, Israel. RESULTS: One hundred and fifty-one eyes of 104 children aged 6.0 ± 3.9 years were included. The mean prediction error (PE) was - 0.08 ± 1.54 diopters (D) with BU II, 0.24 ± 1.46 D with Hoffer-Q, and 0.71 ± 1.92 D with SRKT (P = 0.10). In eyes with axial length (AL) < 22 mm, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.024). In eyes with AL ≥ 22 mm, BU II had a smaller PE than Hoffer-Q (P = 0.048). In children 24 months or older at surgery, BU II had a smaller PE than SRKT and Hoffer-Q (P = 0.012). However, in younger children, no difference was found between the formulae (P = 0.61). For mean k-values ≥ 44.5 D, BU II and Hoffer-Q had a smaller PE than SRKT (P = 0.002). An absolute prediction error < 1.0 D was obtained with BU II in 66% of eyes and SRKT in 35% (P = 0.01). CONCLUSIONS: The BU II formula performed well with a small prediction error. No significant difference in PE was detected overall between the formulae. However, only BU II demonstrated a stable prediction error at varying axial lengths, K-readings, and ages. As the biometric parameters of the developing eye change with growth, the BU II formula offers a reliable and stable option for pediatric IOL calculation.

Orbital nodular fasciitis in the pediatric population: a case report and review of the literature.

A 10-month-old female presented with a rapidly growing, painless mass in the right upper eyelid. Due to suspected malignancy, she underwent an urgent biopsy. Histopathological and immunohistochemical analyses revealed nodular fasciitis. Here, we describe the case and perform a literature review of orbital nodular fasciitis in the pediatric population.

The detrimental effects of delayed intravitreal anti-VEGF therapy for treating retinal pathology: lessons from a forced test-case.

PURPOSE: Determine the anatomical consequences of delaying intravitreal injection (IVI) therapy with anti-vascular endothelial growth factor (anti-VEGF) in patients using treat-and-extend (T&E) protocol. METHODS: Retrospective medical record review of consecutive patients receiving intravitreal anti-VEGF therapy using T&E protocol prior to and during the COVID-19 pandemic. RESULTS: The study included 923 eyes of 691patients; 58.8% (543 eyes), 25% (231 eyes), and 16.2% (149 eyes) had nvAMD, DME, and RVO, respectively. Mean (± SD) patient age was 74.5 ± 11.7 years. Overall, 56.3% of cases had a delay in therapy of ≥ 7 days; specifically, 56.2%, 61.5%, and 49.0% of nvAMD, DME, and RVO cases, respectively, had a delay. The median delay in days, among cases ≥ 7 days late was 21 (IQR 7 to 42) days, with 21(IQR 7 to 45), 22.5(IQR 8 to 42), and 14(IQR 7 to 33.5) days of delay among patients with nvAMD, DME, and RVO, respectively. Delaying therapy by ≥ 7 days resulted in increased CST in 47.5%, 58.5%, and 58.9% of nvAMD, DME, and RVO cases, respectively, with a significant correlation between the length of treatment delay and the increase in CST (Spearman's rho: 0.196; p < 0.001). CONCLUSIONS: Delayed IVI treatment in eyes treated with T&E protocol was associated with increased macular thickness with potential consequences with respect to visual outcome.

Ophthalmic Emergency Visits in the Wake of the COVID 19 Pandemic: Our Experience at a Tertiary Hospital in Israel.

BACKGROUND: In response to the coronavirus disease-2019 (COVID-19) pandemic, routine clinical visits to the ophthalmic emergency department (OED) were deferred, while emergency cases continued to be seen. OBJECTIVES: To assess the consequences of the COVID-19 pandemic for ophthalmic emergencies. METHODS: A retrospective chart analysis of patients who presented to the OED during the peak of the COVID-19 pandemic was conducted. The proportions of traumatic, non-traumatic-urgent, and non-traumatic-non-urgent presentations in 2020 were compared to those of the same time period in 2019. Duration of chief complains and best-corrected visual acuity were also assessed. RESULTS: There were 144 OED visits in 2020 compared to 327 OED visits during the same 3-week-period in 2019. Lower mean age of OED patients was present in 2020. Logarithmic expression (LogMAR) best corrected visual acuity (BVCA) was similar in both years. In 2020 there was a reduction in traumatic, non-traumatic-urgent, and non-traumatic-non-urgent cases compared to 2019 (15.4% reduction, P = 0.038; 57.6% reduction, P = 0.002; 74.6% reduction, P = 0.005, respectively). There was a higher proportion of same-day presentations at commencement of symptoms in 2020 compared with 2019 (52.8% vs. 38.8%, respectively P = 0.006). CONCLUSIONS: During the COVID-19 pandemic, the number of OED visits at a tertiary hospital dropped by more than half. Although the drop in visits was mostly due to decrease in non-traumatic-non-urgent cases, there was also decrease in non-traumatic-urgent presentations with possible important visual consequences. Additional studies should elucidate what happened to these patients.

Effect of age, sex, and body size on the blood biochemistry and physiological constants of dogs from 4 wk. to > 52 wk. of age.

BACKGROUND: Blood biochemistry and reference intervals help to differentiate between healthy and ill dogs as well as to provide information for the prognosis, evaluation, and monitoring; however, these intervals are often obtained from adult animals. It is essential to understand that puppies and adults are physiologically different, which justifies the need to obtain age-specific biochemical reference intervals. The aim of this research was to assess the potential effect of age, sex, body size, and their interaction on routine biochemical analytes and physiological constants (body temperature, heart rate, and respiratory rate). To carry out the research, we selected 197 healthy dogs of both sexes and different body sizes (small, medium and large) classified by age: group I (4-8 wk), group II (9-24 wk), group III (25-52 wk), and group IV (> 52 wk). The biochemical analysis included the measurement of the enzymatic activity of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), and the concentrations of cholesterol, triglycerides, total proteins, albumin, globulins, glucose, urea, and creatinine. Statistical analyses used analysis of variance (ANOVA) and a general linear model (GLM), which allows the comparison of multiple factors at two or more levels (p < 0.05). RESULTS: The results of this study showed that ALT, total protein, albumin, globulin, urea, creatinine, and body temperature levels were lower in puppies than in adult dogs of group IV (p < 0.05), while the enzymatic activity of ALP, LDH, glucose concentration, and heart rate were higher. Whereas sex, body size and the interaction did not show a significant effect (p > 0.05). CONCLUSIONS: Some biochemical components are influenced by age. For this reason, this manuscript contributes with additional data for the clinical interpretation of blood biochemical results in puppies.

Implications of pars planitis-associated cystoid macular edema on visual outcome and management in children.

PURPOSE: Pars planitis is a commonly observed type of pediatric uveitis. The aim of this study was to evaluate the implications of pars planitis-associated cystoid macular edema (CME) on visual outcome and treatment modalities. METHODS: A retrospective review of medical records in a single center with academic practice. RESULTS: Included were 33 children (mean age 8 years, 58 eyes). Eighteen eyes developed CME (31%): in 67% of them, CME was diagnosed at presentation and in 33%, it developed at a mean of 57 months after presentation. Anterior and posterior segment complications were more prevalent in eyes with CME. Papillitis was significantly associated with the development of CME (OR 12.4, 95% CI 2.3 to 65.6, p = 0.003). Patients with CME were 1.7 times more likely to be treated with systemic therapy. By the last follow-up, 50% of patients who never developed CME were without systemic therapy compared with 13% of patients who developed CME (p = 0.034). LogMAR visual acuity improvement between presentation and month 36 was 0.41 for eyes with CME compared with 0.14 for eyes that never developed CME (p = 0.009). CONCLUSION: Pars planitis-associated CME entailed higher prevalence of ocular complications, more frequent use of immunomodulatory therapy, and a lower rate of remission.

Coevolution of cultural intelligence, extended life history, sociality, and brain size in primates.

Explanations for primate brain expansion and the evolution of human cognition and culture remain contentious despite extensive research. While multiple comparative analyses have investigated variation in brain size across primate species, very few have addressed why primates vary in how much they use social learning. Here, we evaluate the hypothesis that the enhanced reliance on socially transmitted behavior observed in some primates has coevolved with enlarged brains, complex sociality, and extended lifespans. Using recently developed phylogenetic comparative methods we show that, across primate species, a measure of social learning proclivity increases with absolute and relative brain volume, longevity (specifically reproductive lifespan), and social group size, correcting for research effort. We also confirm relationships of absolute and relative brain volume with longevity (both juvenile period and reproductive lifespan) and social group size, although longevity is generally the stronger predictor. Relationships between social learning, brain volume, and longevity remain when controlling for maternal investment and are therefore not simply explained as a by-product of the generally slower life history expected for larger brained species. Our findings suggest that both brain expansion and high reliance on culturally transmitted behavior coevolved with sociality and extended lifespan in primates. This coevolution is consistent with the hypothesis that the evolution of large brains, sociality, and long lifespans has promoted reliance on culture, with reliance on culture in turn driving further increases in brain volume, cognitive abilities, and lifespans in some primate lineages.

Gross intestinal morphometry and allometry in primates.

Although it is generally assumed that among mammals and within mammal groups, those species that rely on diets consisting of greater amounts of plant fiber have larger gastrointestinal tracts (GIT), statistical evidence for this simple claim is largely lacking. We compiled a dataset on the length of the small intestine, caecum, and colon in 42 strepsirrhine, platyrrhine, and catarrhine primate species, using specimens with known body mass (BM). We tested the scaling of intestine length with BM, and whether dietary proxies (percentage of leaves and a diet quality index) were significant covariates in these scaling relationships, using two sets of models: one that did not account for the phylogenetic structure of the data, and one that did. Intestine length mainly scaled geometrically at exponents that included 0.33 in the confidence interval; Strepsirrhini exhibited particularly long caeca, while those of Catarrhini were comparatively short. Diet proxies were only significant for the colon and the total large intestine (but not for the small intestine or the caecum), and only in conventional statistics (but not when accounting for phylogeny), indicating the pattern occurred across but not within clades. Compared to terrestrial Carnivora, primates have similar small intestine lengths, but longer large intestines. The data on intestine lengths presented here corroborate recent results on GIT complexity, suggesting that diet, as currently described, does not exhaustively explain GIT anatomy within primate clades.

Primate Brain Anatomy: New Volumetric MRI Measurements for Neuroanatomical Studies.

Since the publication of the primate brain volumetric dataset of Stephan and colleagues in the early 1980s, no major new comparative datasets covering multiple brain regions and a large number of primate species have become available. However, technological and other advances in the last two decades, particularly magnetic resonance imaging (MRI) and the creation of institutions devoted to the collection and preservation of rare brain specimens, provide opportunities to rectify this situation. Here, we present a new dataset including brain region volumetric measurements of 39 species, including 20 species not previously available in the literature, with measurements of 16 brain areas. These volumes were extracted from MRI of 46 brains of 38 species from the Netherlands Institute of Neuroscience Primate Brain Bank, scanned at high resolution with a 9.4-T scanner, plus a further 7 donated MRI of 4 primate species. Partial measurements were made on an additional 8 brains of 5 species. We make the dataset and MRI scans available online in the hope that they will be of value to researchers conducting comparative studies of primate evolution.

Energetics and the evolution of human brain size.

The human brain stands out among mammals by being unusually large. The expensive-tissue hypothesis explains its evolution by proposing a trade-off between the size of the brain and that of the digestive tract, which is smaller than expected for a primate of our body size. Although this hypothesis is widely accepted, empirical support so far has been equivocal. Here we test it in a sample of 100 mammalian species, including 23 primates, by analysing brain size and organ mass data. We found that, controlling for fat-free body mass, brain size is not negatively correlated with the mass of the digestive tract or any other expensive organ, thus refuting the expensive-tissue hypothesis. Nonetheless, consistent with the existence of energy trade-offs with brain size, we find that the size of brains and adipose depots are negatively correlated in mammals, indicating that encephalization and fat storage are compensatory strategies to buffer against starvation. However, these two strategies can be combined if fat storage does not unduly hamper locomotor efficiency. We propose that human encephalization was made possible by a combination of stabilization of energy inputs and a redirection of energy from locomotion, growth and reproduction.

[Nutritional status of adolescents from a cohort of preterm children]. / Estado nutricional de adolescentes pertenecientes a una cohorte de niños nacidos prematuros.

INTRODUCTION: Catch-up growth in preterm-born children occurs in the first months of life, but in some cases, growth recovery takes place in adolescence. The objective of this study was to study the growth and development of preterm-born adolescents from a cohort of preterm infants born between 1995 and 1996, who resided in the cities of Chillán and San Carlos in the Biobío Region, Chile. The results were then compared with term-born adolescents. SUBJECTS AND METHOD: A sample of 91 children from the cohort was studied and compared with 91 term-born adolescents matched for gender, age, and attendance at the same educational institution. The nutritional status was assessed by BMI-for-age, height-for-age, body composition by skinfold, cardiovascular risk due to blood pressure, and waist circumference. RESULTS: There was 23.0% and 24.1% overweight and obesity in preterm-born and term-born adolescents, respectively, with 25.5% of preterm-born and small for gestational age adolescents vs. 14.5% of those born adequate for gestational age were overweight. Lower height was observed in 16.5% and 5.5% of the preterm-born and term-born adolescents, respectively, and with a higher proportion of girls (P<.04). Preterm-born adolescents had a more fat mass than the controls, particularly in the suprailiac skinfold. No significant differences were found in blood pressure and waist circumference. CONCLUSIONS: The results indicate that there is a group of preterm-born children who do not recover height during adolescence, especially girls.

Mutations in the A3 domain of von Willebrand factor inducing combined qualitative and quantitative defects in the protein.

Two unrelated families were recruited in the French Reference Center for von Willebrand Disease with moderate bleeding symptoms associated with low von Willebrand factor (VWF) antigen levels, decreased collagen binding assay, and no or partial response to desmopressin. Genetic analysis showed the presence of heterozygous mutations in the A3 domain away from the collagen-binding surface: 1 never reported previously (p.L1696R) and another (p.P1824H) described in a Spanish family. The mutations were reproduced by site-directed mutagenesis and mutant VWF was expressed in different expression systems, COS-7 cells, baby hamster kidney cells, and in VWF-deficient mice through hydrodynamic injection. p.L1696R and p.P1824H were associated with very low expression levels both in vitro and in vivo, with intracellular retention for p.P1824H. Both homozygous mutants displayed decreased binding to collagen types I and III but also decreased binding to platelet glycoproteins Ib and IIbIIIa. Co-transfections with wild-type VWF partially corrected these defects, except that collagen binding remained abnormal. The in vivo thrombosis response was severely reduced for both heterozygous mutants. In conclusion, we report 2 VWF A3 domain mutations that induce a combined qualitative and quantitative defect.

A murine model to characterize the antithrombotic effect of molecules targeting human von Willebrand factor.

von Willebrand factor (VWF) is a promising target for developing antithrombotic drugs. The absence of accessible animal models impedes the study of specific human VWF (huVWF) targeting molecules in thrombosis. huVWF is not functional in the mouse because of a lack of interaction between huVWF and murine glycoprotein Ib. Using site-directed mutagenesis, we have replaced single or multiple amino acids in huVWF with their murine counterparts to eliminate species incompatibility. Using hydrodynamic injection, we have expressed the different chimeric VWF constructs into VWF(-/-) mice. Only huVWF with a complete murine A1 domain insertion was able to correct bleeding in vivo and form occlusive thrombi in mesenteric vessels after FeCl(3) treatment. Using this model, we tested the antithrombotic effect of monoclonal antibodies against huVWF, blocking its interaction with collagens (mAbs 203 and 505) or with glycoprotein IIbIIIa (mAb 9). The 3 mAbs inhibited the thrombotic process in arterioles of VWF(-/-) mice expressing huVWFmuA1. Inhibiting VWF-interaction with collagens was more potent, emphasizing the potential of such a target as an antithrombotic tool. Our results validate our murine model as a simple in vivo tool to evaluate anti-huVWF agents.

Macrophage LRP1 contributes to the clearance of von Willebrand factor.

The relationship between low-density lipoprotein receptor-related protein-1 (LRP1) and von Willebrand factor (VWF) has remained elusive for years. Indeed, despite a reported absence of interaction between both proteins, liver-specific deletion of LRP1 results in increased VWF levels. To investigate this discrepancy, we used mice with a macrophage-specific deficiency of LRP1 (macLRP1(-)) because we previously found that macrophages dominate VWF clearance. Basal VWF levels were increased in macLRP1(-) mice compared with control mice (1.6 ± 0.4 vs 1.0 ± 0.4 U/mL). Clearance experiments revealed that half-life of human VWF was significantly increased in macLRP1(-) mice. Ubiquitous blocking of LRP1 or additional lipoprotein receptors by overexpressing receptor-associated protein in macLRP1(-) mice did not result in further rise of VWF levels (0.1 ± 0.2 U/mL), in contrast to macLRP1(+) mice (rise in VWF, 0.8 ± 0.4 U/mL). This points to macLRP1 being the only lipoprotein receptor regulating VWF levels. When testing the mechanism(s) involved, we observed that VWF-coated beads adhered efficiently to LRP1 but only when exposed to shear forces exceeding 2.5 dyne/cm(2), implying the existence of shear stress-dependent interactions. Furthermore, a mechanism involving ß2-integrins that binds both VWF and LRP1 also is implicated because inhibition of ß2-integrins led to increased VWF levels in control (rise, 0.19 ± 0.16 U/mL) but not in macLRP1(-) mice (0.08 ± 0.15 U/mL).

Biochemical parameters in the blood of Holstein calves given immunoglobulin Y-supplemented colostrums.

BACKGROUND: In any calf rearing system it is desirable to obtain healthy animals, and reduce morbidity, mortality, and economic losses. Bovine syndesmochorial placentation prevents the direct transfer of bovine immunoglobulins to the fetus, and calves are born hypogammaglobulinemic. These calves therefore require colostrum immediately after birth. Colostrum is rich in immunoglobulins (Ig) and its consumption results in the transfer of passive immunity to calves. The Ig absorption occurs within the first 12 h after birth. Immunoglobulin Y (IgY), derived from chicken egg yolk, has been used in the prevention and control of diseases affecting calves because it is very similar in structure and function to immunoglobulin G (IgG). In the current study, we sought to establish whether administration routes of colostrum supplemented with avian IgY affected passive immunity in calves. RESULTS: No significant differences were observed with respect to route of administration for colostrum. However, we did observe some differences in certain interactions between the various treatments. Calves fed colostrum containing egg yolk had higher levels of TP, ALB, and IgG, along with increased GGT activity. CONCLUSIONS: Our results suggest that supplementing colostrum with egg yolk has a beneficial effect when given to calves, regardless of administration route.

Visual acuity improvement in children with albinism beyond the first decade of life.

PURPOSE: To determine if visual maturation continues beyond the first decade of life in children with albinism and whether this is related to albinism type, presence of nystagmus, eye muscle surgery or refractive errors. DESIGN: Case series based on retrospective study of children with confirmed genetic diagnosis of albinism. METHODS: Clinical data were obtained from medical files of children examined during school years, including albinism type, visual acuity, eye muscle surgery, nystagmus, and others on different visits (Visit 1: ages 7-9; Visit 2: ages: 10-12; Visit 3: ages 13-16; Visit 4: ages >16). RESULTS: Seventy-five children with albinism were included in the study. Patients were divided into different groups according to the albinism type including OCA1A: 17; OCA1B: 28; OCA2: 26; HPS: 3; OCA4: 1. Follow-up ranged from 3-13 years. Progressive visual acuity improvement was seen in all three main groups. T-test paired samples showed a statistically significant improvement when comparing vision from Visit 1 and Visit 3 in both OCA1A and OCA2 groups, with a mean vision improvement of 2 lines. There was no correlation between visual improvement and refractive error, eye muscle surgery or nystagmus. CONCLUSION: An improved visual performance was seen in a large percentage of children with albinism during the second decade of life. The reason for this late improvement in vision is not clear but may be related to late foveal maturation or improvement in nystagmus with time. This information is useful for clinicians of these patients and when counseling parents.

Total exudative retinal detachment in a child with pars planitis- a challenging case with optimistic results.

We describe a case report of pediatric pars planitis complicated with massive exudative retinal detachment (ERD). A 7-year-old presented with visual acuity (VA) in the right eye (RE) of 6/9 and in the left eye (LE) 6/15. Fundoscopy revealed BE inferior retinoschisis, vitritis and snowballs. He was treated with systemic immunosuppressants. RE retinoschisis resolved within 2 months. Three years later presented with LE VA 6/60 and total ERD. Systemic and intravitreal steroids were administered. Due to refractoriness, he underwent 360° scleral buckle and drainage of subretinal fluid. No retinal breaks or traction were detected. Five months postoperatively LE VA was 6/7.5. Long-term stable outcome was maintained. We report a challenging total ERD as a complication of pars planitis. Although extensive and non-responsive to medical therapy, complete resolution and improvement in vision was achieved with surgical intervention and systemic immunosuppression. We speculate that uncontrolled chronic vasculitic process culminated in diffuse ERD.

Enhanced S-Cone Syndrome Masquerading as TORCH in an Infant and a Toddler.

PURPOSE: To report two cases masquerading as TORCH but eventually diagnosed with Enhanced S-cone Syndrome (ESCS). METHODS: Descriptive case report. RESULTS: Case 1: A ten-month-old boy presented with high hypermetropia, strabismus and bilateral chorioretinal pigmented scars with a history of cat scratch of his mother during pregnancy. He was treated for suspected toxoplasma retinitis. Choroidal neovascular membranes (CNV) were diagnosed bilaterally and treated with intravitreal bevacizumab. Genetic testing showed homozygote mutation in NR2E3 gene. Case 2: A two-year old girl presented with bilateral high hypermetropia and strabismus. Funduscopy revealed extrafoveal chorioretinal lesions and surrounding subretinal fibrosis. An elevated titer of anti-toxocara IgG antibodies was detected and managed accordingly. LE CNV was diagnosed and treated with intravitreal bevacizumab. Genetic testing disclosed homozygote mutation in NR2E3. CONCLUSION: Ocular manifestations in ESCS can be reminiscent to TORCH. CNV may develop with an incidence of 15%. We report the youngest patient with ESCS-associated CNV.

Induction of heme oxygenase-1 in factor VIII-deficient mice reduces the immune response to therapeutic factor VIII.

Replacement therapy with exogenous factor VIII (FVIII) to treat hemorrhages induces anti-FVIII inhibitory immunoglobulin G in up to 30% of patients with hemophilia A. Chronic inflammation associated with recurrent bleedings is a proposed risk factor for FVIII inhibitor development. Heme oxygenase-1 (HO-1) is a stress-inducible enzyme with potent anti-inflammatory activity. Here, we demonstrate that induction of HO-1 before FVIII administration drastically reduces the onset of the anti-FVIII humoral immune response. The protective effect was specific for HO-1 because it was reproduced on administration of the end products of HO-1 activity, carbon monoxide, and bilirubin, and prevented by the pharmacologic inhibition of HO-1 using tin mesoporphyrin IX. HO-1 induction was associated with decreased major histocompatibility complex class II expression by splenic antigen-presenting cells and reduced T-cell proliferation. Triggering the endogenous anti-inflammatory machinery before FVIII administration may represent a novel therapeutic option for preventing the development of FVIII inhibitors in hemophilia A patients.

Red blood cells morphology and morphometry in adult, senior, and geriatricians dogs by optical and scanning electron microscopy.

Red blood cells (RBC) morphologic evaluation through microscopy optical (OM) and SEM, provides information to forecast, evaluate, and monitor the functioning of many organs. Factors, such aging and diseases affect RBC morphology in both, human and animals. SEM is useful to evaluate RBC morphology, although its use in diagnosis and evaluation in dogs is limited, due to the availability and cost. The aim of this research was to assess the normal RBC morphology in adult, senior and geriatrician dogs, clinically healthy by OM and SEM. In addition to evaluating the age effect, sex, body size, and their interaction on erythrocyte morphometry. To carry out the research 152 blood samples were evaluated from dogs of different sexes and body sizes (small, medium, and large). Three groups were made based on dogs age: group I adults (1-7.9 years old), group II senior (8-11.9 years old), and group III geriatricians (>12 years old). Erythrocyte parameters were evaluated by OM (diameter, height, and axial ratio). Per each dog, the parameters of 20 erythrocytes were measured. A total of 2,600 cells were scanned with the AmScope™ Software scale. In addition, the RBC morphology was evaluated by SEM. Statistical analyses used analysis of variance and a general linear model, which allows the comparison of multiple factors at two or more levels (p < 0.05). The results of this study showed that diameter and height were lower in adult dogs than in senior and geriatrician dogs (p < 0.05). Whereas, sex, body size, and the interaction did not show a significant effect (p > 0.05). Additionally, some images of anisocytosis, polychromasia, and poikilocytosis (echinocytes, acanthocytes, codocytes, spherocytes, stomatocytes, dacryocytes quatrefoil, and elliptocytes) were obtained by OM and SEM. Our study provides information about the morphological and morphometry alterations of adult, senior, and geriatrician dogs RBC. This work contributes to future investigations and the diagnosing diseases, where it is necessary to evaluate the morphology of RBC.