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

Abstract

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.

Migrating Azygos Vein and Vanishing Azygos Lobe: Mdct Findings

“…The azygos lobe is a congenital variant with an incidence of about 0.4-1.2% of the population [2]. It occurs when the azygos vein pen- …”

Response to letter: The supplemental measurement data of a case of azygos lobe for its clinical implications

“…In our article (Arakawa et al, 2008), we stated that our study is the third report of its kind involving Japanese individuals. As suggested by Dr. Das, Kobayashi et al (1995) reported a case of right human azygos lobe in the Kagawa Medical School.…”

“…Our report of the human azygos lobe (Arakawa et al, 2008) described the anatomical detail of the branching pattern of the bronchus, pulmonary arteries, and veins. Our article focused the bronchial branching patterns to determine the better procedure of the therapeutic postural drainage for the patient with the azygos lobe, and therefore, we did not represent these dimensions in our article.…”

“…Additionally, in our article (Arakawa et al, 2008), we stated that the postural drainage for patients with this lobe recommended the at least 308 right sided neck flexion. However, as suggested by Dr. Das, this opinion is a speculation, as this is the cadaveric anatomical study.…”

Azygous lobe: a normal variant of pulmonary anatomy

“…The azygous lobe is a normal anatomical variant with reported incidence of 0.2–1.2% (1). We report a case of a 51-year-old man with past medical history significant for drug and alcohol abuse, who presented to the emergency department with altered mental status and hypoxic respiratory failure.…”