Marco Antonio De Angelis

Orbital asymmetry in development: an anatomical study

The aim of this study was to analyze the human orbital asymmetry during development. One hundred twenty-seven identified human dry skulls, with sex, age, date and cause of death record, in good preservation state, were used. Bones that had evidence of trauma, malformations or other pathology were excluded. The sample was divided into 4 age groups: I – intra-uterine life (n=20), II – newborn up to 2 years old (n=43), III – three up to 20 years old (n=27) and IV – 21 up to 76 years old (n=37). The skulls were photographed in norma frontalis and images were analyzed with the software AutoCAD® 2002 in real scale. The obtained measurements were: greater horizontal diameter (HD), greater vertical diameter (VD), orbital perimeter and orbital base area. All skulls showed asymmetry in all measures, except 4 of them that showed symmetry in VD and perimeter. The asymmetry occurred in all ages, being calculated as a percent rate for VD – 2.73%, HD – 4.48%, area – 4.77% and perimeter – 2.47%. There was predominance in asymmetric rate in female skulls and only in the group II the difference between gender was statistically significant (p<0.05). The right orbit presented larger measures. The asymmetric rate was assumed as the normal anatomic pattern.

Biometric Study of the Optic Canal during Cranial Development

To study optic canal dimensions and symmetry during cranial development, 146 silicon rubber left- and right-side models of the optic canal were cast from 51 dry skulls and 22 individual bones. The sample was divided in three age groups: fetuses (including newborns), children and adults with ages ranging from seven months of fetal life to 68-year-old. A digital caliper was used to measure the optic canal orbital and cranial diameters as well as model length. Results for the right and the left sides were, respectively, in millimeters: a) Maximum diameter of the orbital opening: fetuses, 4.68/4.47—children, 5.51/5.41—adults, 5.43/5.34; b) Minimum diameter of the orbital opening: fetuses, 2.89/2.84—children, 3.54/3.61—adults, 3.78/3.73; c) Diameter of the cranial opening: fetuses, 3.79/3.76—children, 4.67/4.72—adults, 5.24/5.43; d) Length of the optic canal: fetuses, 3.27/3.05—children, 3.93/3.71—adults 4.94/5.21. The diameter of the cranial opening of the optic canal increases significantly (p < 0.001) during the fetal period and throughout child and adulthood. The greater and smaller orbital apertures increase during the fetal period and during childhood, keeping the same size in adulthood. Optic canal length increases at some point between childhood and adulthood. Concerning symmetry, the only significant difference found was greater right than left optic canal diameter on the orbital side.

Efeitos agudos da ventilação mecânica com hiperoxia na morfometria do diafragma de ratos

BACKGROUND: Prolonged mechanical ventilatory support (MVS) combined with high oxygen concentrations has a negative impact on diaphragm function. However, the acute effects of MVS with hyperoxia have not been elucidated. Objective: To analyze the acute effects of mechanical ventilation with hyperoxia on the morphometry of the rat diaphragm. METHODS: An experimental, prospective study was conducted with Wistar rats (weight: 400±20 g), which were randomly allocated to two groups. The control group (n=4) was anesthetized, tracheostomized and kept spontaneously breathing room air for 90 minutes. The experimental group (n=5) was also anesthetized, curarized, tracheostomized and kept in controlled mechanical ventilation for the same amount of time. Both groups were submitted to median thoracotomy for sample collection of costal fibers from the diaphragm muscle, which were sectioned every 5 μm and stained with hematoxylin and eosin for the morphometric study. Independent Students t tests were employed to investigate differences between groups, with a significance level of p<0.05. RESULTS: There were no signs of acute muscle lesions, however the blood capillaries became dilated in the experimental group. The mean morphometric data related to the maximum cross-sectional diameter of the diaphragm costal fibers were 61.78 ±17.79 µm and 70.75±9.93 µm (p=0.045) for the control and experimental groups, respectively. CONCLUSIONS: Short-term mechanical ventilation with hyperoxia led to significant microvascular and muscle changes, which may reflect the onset of an inflammatory process.

The External Opening of the Cochlear Aqueduct in Infants and Adults

Objective: The purpose of the present study is the description of the shape and area of the cochlear aqueduct (CA) opening by means of molds obtained from infant and adult temporal bones. Material and Methods: Through molding techniques the evaluation was performed in 118 temporal bones of infants (5–60 months) and of adults (19–89 years), dimensions and shapes being evaluated through computerized image processing. Results and Conclusions: The data shows that the area of the opening is significantly smaller in children than in adults (7.32 ± 3.32 versus 18.48 ± 6.42 mm2). In infants, in 56% the shape of the opening was triangular; in adults triangularity was 100%. The variability in the shape and size of the CA opening in infants suggests adaptations of the CA opening during cranial growth.