Quantitative Anatomy of the Growing Lungs in the Human Fetus

Abstract

Using anatomical, digital, and statistical methods we examined the three-dimensional growth of the lungs in 67 human fetuses aged 16–25 weeks. The lung dimensions revealed no sex differences. The transverse and sagittal diameters and the base circumference were greater in the right lungs while the lengths of anterior and posterior margins and the lung height were greater in the left lungs. The best-fit curves for all the lung parameters were natural logarithmic models. The transverse-to-sagittal diameter ratio remained stable and averaged 0.56 ± 0.08 and 0.52 ± 0.08 for the right and left lungs, respectively. For the right and left lungs, the transverse diameter-to-height ratio significantly increased from 0.74 ± 0.09 to 0.92 ± 0.08 and from 0.56 ± 0.07 to 0.79 ± 0.09, respectively. The sagittal diameter-to-height ratio significantly increased from 1.41 ± 0.23 to 1.66 ± 0.18 in the right lung, and from 1.27 ± 0.17 to 1.48 ± 0.22 in the left lung. In the fetal lungs, their proportionate increase in transverse and sagittal diameters considerably accelerates with relation to the lung height. The lung dimensions in the fetus are relevant in the evaluation of the normative pulmonary growth and the diagnosis of pulmonary hypoplasia.

Fetal Thoracic Circumference and Lung Volume and Their Relation to Fetal Size and Pulmonary Artery Blood Flow

“…Contrary to earlier observation of similar right and left lung length, 24 we found significantly shorter right lung length compared to the left. This finding agrees with results from postmortem fetal lung measurements, 25 and seems reasonable as the left side of the diaphragm is placed lower than the right. Our LV measures corresponded to those of Moeglin et al, whose 2D‐based method we adapted 20 .…”

Three- dimensional reconstruction of the thorax in the mongoose (Herpestes ichneumon)

“…Concerning the diameters of the thorax, as in the mongoose, the wood pigeon (Columba palumbus) has a greater sagittal diameter in the right lung whereas a greater transverse diameter in the left lung (Alumeri et al, 2013). In the human fetus (Szpinda et al, 2015), similar to the findings obtained for the mongoose, the transverse and sagittal diameters as well as the height were found to be greater in the right lung than in the left.…”

“…Amabile et al (2016) assessed the 3D reconstruction model of the human thorax and found the thorax and lung volumes to be greater in males than in females. However, there was no significant difference observed in human fetal lung volumes due to genders (Szpinda et al, 2015).…”

“…In this study, some measurements of thoracic cavity, lungs and sternum were taken from 3D model of the thorax depending on the literature ( Ramadan et al, 2010;Szpinda et al, 2015;Plesis, 2015) (Fig. 1-4) and indexes were calculated from these measurements depending on the literature (Ramadan et al, 2010;Szpinda et al, 2015).…”