An uncommon extrapulmonary sequestration located in the upper posterior mediastinum associated with the azygos lobe in a child

The prevalence of the azygos lobe: A meta-analysis of 1,033,083 subjects

The azygos lobe (AL) is an accessory lobe of the right lung with prevalence between 0.4 and 1.2%. The aim of the present review is to provide a better estimate of the frequency of the AL and to examine its relationships with other variables such as population, diagnostic methods, and co-occurring illnesses. Studies published between 1899 and October 2020 were searched through three electronic databases; Google Scholar, PubMed, and JSTOR. Titles, abstracts, and full texts of the retrieved entries were screened to determine their appropriateness for inclusion. A total of 88 studies relating to 1,033,083 subjects met the inclusion criteria. A random-effects meta-analysis yielded an overall prevalence of 0.30% (95% CI: 0.0024-0.0035, I²  = 97.9%). Linear regression and subgroup analysis revealed a negative correlation (ρ = -0.540, p <0.001) between AL prevalence and sample size; studies with smaller sample sizes had higher prevalences. The AL prevalence in individuals with congenital pulmonary defects, 5.2% (95% CI: 0.0018-0.0086, I²  = 0%), was 17 times higher than the overall prevalence (z = 6.65, p <0.001), suggesting associations with other abnormalities and possibly a genetic predisposition. In addition to an evidence-based synthesis of AL prevalence, this study demonstrates publication bias and small-study effects in the anatomy literature. Awareness of the AL is crucial for radiologists when they interpret unusual radiological findings and for surgeons when they operate in the region.

Clinical cardiac assessment in newborns with prenatally diagnosed intrathoracic masses

Background

Congenital space-occupying thoracic malformations and diaphragmatic hernia have in common pulmonary hypoplasia. Our study aims to assess cardiac involvement during post-natal adaptation.

Methods

A retrospective study was carried out on newborns with prenatally diagnosed intrathoracic mass. Gathering for respiratory distress syndrome (RDS), 35 neonates were compared for clinical course, cardiovascular enzymes, ECG, and ultrasound.

Results

The analysis revealed a high left heart defect rate in patients with severe RDS, without being influenced by the laterality. Ultrasound or laboratory assessment did not detect altered cardiac dimension or cardiomyopathy. Solely ECG signs of right ventricular strain were found. Increased QT-dispersion, T-wave and cardiac variability alterations in the first hours were all expression of non-specific cardiac repolarization disorders but predict worse outcome.

Conclusions

Although RDS is the predominant symptom, slight cardiac dysfunctions should be recognized for prompt treatment. Conventional examinations for postnatal adaption should be integrated by complementary investigations.

A human case of an azygos lobe: determining an anatomical basis for its therapeutic postural drainage

An azygos lobe of the human lung is one of the most common lung malformations. However, there are only a few anatomical reports concerning the bronchial and blood supply to this lobe. We encountered the azygos lobe in an anatomical dissection course. The azygos lobe of this case was examined macroscopically and lung parenchyma, including alveoli, terminal bronchioles, and bronchial arteries and veins, was partially removed under a stereoscopic microscope. The azygos lobe was situated medial to the superior lobe and superior to the hilum of the right lung. The parietal pleura wrapped around the azygos vein like a mesentery to form the "meso-azygos." Partial removal of the lung parenchyma revealed that the azygos lobe received bronchial branches from the medial components of the apical and anterior branches of the apical segmental bronchus (B(1)a and B(1)b), and that these bronchial branches were bent excessively in a medial direction from the parent bronchial trunk. For therapeutic drainage of secretions from a right azygos lobe, a 45 degrees upright sitting posture with the neck flexed to the right side is recommended, because in this posture the bronchial branches to the azygos lobe assume a more vertical orientation to facilitate greater dependent drainage of this lobe.