Morphometric study of the ascending aorta in human fetuses

Early Onset of Atherosclerosis of The Carotid Bifurcation in Newborn Cadavers

INTRODUCTION

The anatomy of arterial bifurcations affects blood flow and has a significant role in the development of vascular disease. Therefore, it is important to know the structural characteristics of the Common Carotid Artery (CCA) and its branches for early onset of atherosclerosis in newborns.

AIM

The present study was conducted to evaluate the characteristics of CCA in newborn cadavers.

MATERIALS AND METHODS

Eight carotid arteries obtained from newborn cadavers were used. The outflow to inflow area ratios was calculated to evaluate vessel diameters. Additionally, scanning electron and light microscopic investigations were conducted with tissue samples. The brachial artery of each cadaver was used as controls. Correlation between area ratios and atherosclerotic endothelial damage was determined.

RESULTS

Light microscopic investigations demonstrated that control group sections showed no positivity for Oil red O staining, while carotid bifurcation regions depicted widespread occurrence of intimal lipid accumulations. Scanning electron microscopic examination of control group sections presented regular endothelial topography, while carotid bifurcation region topography exhibited numerous blood cells and separated endothelial cells. Fibrin accumulation on endothelial surface in low area ratios was another important finding in the examination of its endothelial surface degeneration. The above-mentioned morphological findings seemed to be quite parallel to outflow to inflow area ratio data favouring low area and degeneration.

CONCLUSION

The correlation between area ratios and the histological characteristic of cerebral vessels of newborn cadavers indicate that early stages of atherosclerosis began in early embryologic life.

Morphometric evaluation of the aortic root in stillborns

OBJECTIVE

To describe the dimensions and amount of collagen in the aortic root of autopsied fetuses at different gestational ages.

MATERIAL AND METHODS

40 samples of aortic roots were selected from autopsied fetuses with gestational ages ranging between 20 and 40 weeks. The thickness and the area of the aortic wall were analyzed on slides stained with Hematoxylin and Eosin, and the collagen was quantified on slides stained with Picrosirius, by using an image analyzing system.

RESULTS

A positive correlation was observed between the thickness of the media layer of the aortic wall and the gestational age. There was a positive and significant correlation between the percentage of collagen in the aortic wall with gestational age and fetal weight. The correlation between gestational age and the area of the aortic root circumference was positive and significant. And the correlation between the aortic diameter and the gestational age as well as fetal length was positive and significant.

CONCLUSION

The thickness of the media layer, the amount of collagen in the aortic wall, the area of the aortic root circumference and the aortic diameter rose with the increase of the gestational age. Thus, the morphological analysis of the aortic root may help as a parameter during the follow-up of inter-uterine growth and fetal development.

Noninvasive technique for the diagnosis of patent ductus arteriosus in premature infants by analyzing pulse wave phases on photoplethysmography signals measured in the right hand and the left foot

Objective

To evaluate the impact of patent ductus arteriosus (PDA) on the pulse phase difference (PPD) between the left foot (postductal region) and the right hand (preductal region).

Materials and Methods

PPD was determined from arterial photoplethysmography signals (pulse waves) measured by infrared sensors routinely used for pulse oximetry in 56 premature infants less than 32 weeks gestation. Only infants with significant PDA (sPDA) diagnosed by echocardiography were treated with ibuprofen (for 3 days). Patients were classified according to whether or not they responded (Success/Failure) to this treatment. The Control group was composed of infants in whom ductus had already closed spontaneously at the time of the first echocardiography. The 3 groups were compared in terms of PPD at the beginning (T1) and at the end (T2) of the study. For patients in the Failure (n = 17) and Success groups (n = 18), T1 corresponded to the first day of treatment and T2 to the day after completion of the course of ibuprofen. In the Control group (n = 21), T1 corresponded to 1 to 3 days of life (DOL), and T2 to 4–6 DOL.

Results

Compared to the Control group, PPD was higher in the Failure (at T1 and T2) and Success (at T1) groups characterized by sPDA. After ibuprofen therapy, PPD in the Success group decreased to about the level observed in the Control group. The area under the ROC curve of PPD for the diagnosis of sPDA was 0.98 (95% CI 0.96–1); for an optimal cut-off of PPD ≥1.65 deg/cm, the sensitivity was 94.2% and the specificity was 98.3%.

Conclusion

In this study, PPD was correlated with ductus arteriosus status evaluated by echocardiography, indicating involvement of the ductal shunt in the mechanism of redistribution in systemic vascular territories. PPD can be considered for the diagnosis of hemodynamically significant PDA.

Quantitative anatomy of the growing abdominal aorta in human fetuses: an anatomical, digital and statistical study

Background

Advances in perinatal medicine have required an extensive knowledge of fetal aorto-iliac measurements. The present study was performed to compile reference data for dimensions of the abdominal aorta at varying gestational ages.

Material/Methods

Using the methods of anatomical dissection, digital-image analysis (Leica QWin Pro 16 system), and statistical analysis (Student’s t-test, one-way ANOVA, post-hoc RIR Tukey test, regression analysis, and Wilcoxon signed-rank test), the growth of length (mm), proximal and distal external diameters (mm), and volume (mm³) of the abdominal aorta in 124 (60 male, 64 female) spontaneously aborted human fetuses aged 15–34 weeks was examined.

Results

No significant male-female differences were found. The length ranged from 9.35±1.24 to 36.29±4.98 mm, according to the linear function y=−14.596+1.519 × Age ±2.639 (R²=0.92; p<0.0001). The proximal external diameter varied from 1.18±0.25 to 5.19±0.49 mm, according to the linear pattern y=−2.065+0.212 × Age ±0.348 (R²=0.92; p<0.0001). The distal external diameter increased from 1.03±0.23 to 4.92±0.46 mm, in accordance with the linear model y=−2.097+0.203 × Age ±0.351 (R²=0.92; p<0.0001). Both length and proximal external diameter of the abdominal aorta indicated a proportionate evolution, because the length-to-proximal external diameter ratio was stable, following the linear function y=7.724–0.017 × Age ±0.925. The abdominal aorta volume ranged from 9.6±4.5 to 740.5±201.8 mm³, given by the quadratic function y=911–101 × Age +2.838 × Age² ±78 (R²=0.89; p<0.0001).

Conclusions

There are no significant differences between males and females for morphometric parameters of the abdominal aorta. The abdominal aorta grows linearly in both length and diameters, and parabolically in volume. These detailed morphometric data of the abdominal aorta provide a database for intra-uterine echographic examinations in the early diagnosis, monitoring and management of aorto-iliac malformations.

The normal growth of the common iliac arteries in human fetuses - an anatomical, digital and statistical study

BACKGROUND

The present study was carried out to compile normative data for dimensions of the common iliac arteries at varying gestational ages.

MATERIAL/METHODS

We used anatomical dissection, digital-image analysis (system of Leica QWin Pro 16) and statistical analysis (Student T test, one-way ANOVA, post-hoc RIR Tukey test, and regression analysis) to examine the increase in length (mm), proximal external diameter (mm), and volume (mm³) of the common iliac arteries in 124 (60 males, 64 females) spontaneously aborted human fetuses aged 15-34 weeks.

RESULTS

Neither sex nor right-left significant differences were found (P>0.05). The length ranged from 4.76 ± 1.05 to 15.38 ± 1.60 mm on the right, and from 4.92 ± 1.33 to 14.91 ± 1.25 mm on the left, according to the linear functions y=-3.598+0.585 × Age ± 1.522 (R²=0.83) and y=-3.107+0.554 × Age ± 1.444 (R²=0.83). The proximal external diameter increased from 0.66 ± 0.19 to 2.30 ± 0.42 mm on the right, and from 0.66 ± 0.14 to 2.16 ± 0.42 mm on the left, according to the quadratic models y=1.392-0.110 × Age + 0.004 × Age² ± 0.285 (R²=0.77) and y=1.283-0.099 × Age + 0.004 × Age² ± 0.238 (R²=0.81). The volumes were increasing from 1.93 ± 1.74 to 66.95 ± 29.31 mm³ on the right, and from 1.91 ± 1.65 to 56.86 ± 25.17 mm³ on the left, given by the quadratic functions: y=99.69-10.60 × Age+0.28 7 × Age² ± 14.40 (R²=0.67) and y=82.62-8.86 × Age + 0.242 × Age² ± 11.60 (R²=0.71).

CONCLUSIONS

The common iliac arteries grow linearly in length, and parabolically in both diameter and volume. The right common iliac artery constitutes a predominant vessel in relation to its length, external diameter and volume. The morphometric data on the common iliac arteries may serve as a useful reference in the prenatal diagnosis and monitoring of congenital aorto-iliac abnormalities.

Development of the abdominal aorta and iliac arteries during the fetal period: a morphometric study

PURPOSE

This study aimed to determine the location and morphometric development of the fetal abdominal aorta and the iliac arteries.

METHODS

The study was carried out between 1996 and 2008 on 172 spontaneously aborted human fetuses (76 males and 96 females) aged between 9 and 40 weeks. None of the fetuses had any external pathology or anomaly. The location of the abdominal aorta was determined in reference to the vertebral column. This was followed by measurements of the lengths, external diameters of the origin of the aorta, and bifurcation of aorta as well as the bifurcation angles of the abdominal aorta. The vertebral levels at which the abdominal aorta started and bifurcated were determined. The lengths and external diameters of the common iliac arteries, diameters of the internal and external iliac arteries, and lengths of the external iliac arteries were measured. The vertebral levels of bifurcation of the common iliac arteries were determined.

RESULTS

The fetal abdominal aorta lay in the midline, in front of the vertebral column. The mean bifurcation angle of the abdominal aorta was greater than adults in the third trimester and at full term. The lengths and diameters of the abdominal aorta and the iliac arteries increased with gestational age, and significant positive correlations were found. There were no sex or laterality differences in either parameter. External diameter of the internal iliac artery was larger than that of the external iliac artery. Bifurcation of the abdominal aorta to the common iliac arteries was more inferior compared to the adults, and these levels rose with gestational age.

CONCLUSION

The morphometric parameters and location of the fetal abdominal aorta and the iliac arteries were determined by the present study. We conclude that the abdominal aorta lay in the midsagittal plane. The bifurcation level of the abdominal aorta arose with gestational age and at full term, and reaches to the same level as adults. In the early fetal period, the bifurcation level of the common iliac artery was more inferior compared to the adults, and they reach the adult positions around full term. The diameter of the internal iliac artery was nearly one and a half times larger than the external iliac artery. The findings of this study would be present, detailed information about the development of the abdominal aorta and the iliac arteries; this will also contribute to radiological (ultrasound and MR) studies in the intrauterine period.