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A Moment in History

Self-portrait, Henry Vandyke Carter, MD (Public Domain)
Self-portrait, Henry Vandyke Carter, MD (Public Domain)

Henry Vandyke Carter, MD
(1831 – 1897)

English physician, surgeon, medical artist, and a pioneer in leprosy and mycetoma studies.  HV Carter was born in Yorkshire in 1831. He was the son of Henry Barlow Carter, a well-known artist and it is possible that he honed his natural talents with his father. His mother picked his middle name after a famous painter, Anthony Van Dyck. This is probably why his name is sometimes shown as Henry Van Dyke Carter, although the most common presentation of his middle name is Vandyke.

Having problems to finance his medical studies, HV Carter trained as an apothecary and later as an anatomical demonstrator at St. George’s Hospital in London, where he met Henry Gray (1872-1861), who was at the time the anatomical lecturer. Having seen the quality of HV Carter’s drawings, Henry Gray teamed with him to produce one of the most popular and longer-lived anatomy books in history: “Gray’s Anatomy”, which was first published in late 1857.  The book itself, about which many papers have been written, was immediately accepted and praised because of the clarity of the text as well as the incredible drawings of Henry Vandyke Carter.

While working on the book’s drawings, HV Carter continued his studies and received his MD in 1856.

In spite of initially being offered a co-authorship of the book, Dr. Carter was relegated to the position of illustrator by Henry Gray and never saw the royalties that the book could have generated for him. For all his work and dedication, Dr. Carter only received a one-time payment of 150 pounds. Dr.  Carter never worked again with Gray, who died of smallpox only a few years later.

Frustrated, Dr. Carter took the exams for the India Medical Service.  In 1858 he joined as an Assistant Surgeon and later became a professor of anatomy and physiology. Even later he served as a Civil Surgeon. During his tenure with the India Medical Service he attained the ranks of Surgeon, Surgeon-Major, Surgeon-Lieutenant-Colonel, and Brigade-Surgeon.

Dr. Carter dedicated the rest of his life to the study of leprosy, and other ailments typical of India at that time. He held several important offices, including that of Dean of the Medical School of the University of Bombay. In 1890, after his retirement, he was appointed Honorary Physician to the Queen.

Dr. Henry Vandyke Carter died of tuberculosis in 1897.

Personal note: Had history been different, this famous book would have been called “Gray and Carter’s Anatomy” and Dr. Carter never gone to India. His legacy is still seen in the images of the thousands of copies of “Gray’s Anatomy” throughout the world and the many reproductions of his work available on the Internet. We are proud to use some of his images in this blog. The image accompanying this article is a self-portrait of Dr. Carter. Click on the image for a larger depiction. Dr. Miranda

Sources:
1. “Obituary: Henry Vandyke Carter” Br Med J (1897);1:1256-7
2. “The Anatomist: A True Story of ‘Gray’s Anatomy” Hayes W. (2007) USA: Ballantine
3. “A Glimpse of Our Past: Henry Gray’s Anatomy” Pearce, JMS. J Clin Anat (2009) 22:291–295
4. “Henry Gray and Henry Vandyke Carter: Creators of a famous textbook” Roberts S. J Med Biogr (2000) 8:206–212.
5. “Henry Vandyke Carter and his meritorious works in India” Tappa, DM et al. Indian J Dermatol Venereol Leprol (2011) 77:101-3


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The Azygos Lobe


This article was written by Claudio Rodrigo Molina, Josefa Catalán Lobo, and Carolina Becker Fehlandt. We thank them for their contribution to Medical Terminology Daily.


The azygos lobe, also commonly referred to as the" accessory lobe of the azygos vein", was first described in 1877 by Heinrich Wrisberg. It is seen in 0,4 % of chest X-rays; 1,5% in high resolution CT, and 1% in anatomical dissections. It is not a true accessory pulmonary lobe as it does not have its own bronchus and does not correspond to a specific bronchopulmonary segment, the “azygos lobe”, is located at the apicomedial portion of the upper right lobe and it separated from the remainder of the upper lobe by a fissure (Denega et al, 2015; Özdemir et al, 2017)

A convex-shaped fissure is created by the course of the vein bearing towards the medial side of the right lung to join with the superior vena cava. Its formation is a result of an unusual embryogenic migration of the posterior cardinal vein; which is a precursor of the azygos vein (Denega et al, 2015).

Instead of sliding over the lung medially, the vein invaginates into the parenchyma of the lung and becomes enveloped by layer of pleural folds, forming a mesentery-like structure, also called “mesoazygos”. Further migration into the lung as it passes towards the right hilum creates a convex semicircular fissure with the vein located at the base of the fissure. This fissure can be identified in an X-ray chest image as a coma-shaped (“Teardrop sign”) or curved linear shadow in the paramediastinal region of the right lung; it terminates at the level of second costal cartilage (Akhtar et al, 2018; Caceres et al, 1993). The lower portion of the azygos fissure is teardrop-shaped and its contains the azygos vein (Özdemir et al, 2017; Kotovet al, 2017).

The pathway of the vein within the lung is subject to individual variation, and this defines the position of the fissure within the apex of the upper lobe. The most superior portion of the fissure adopts a triangular form, called the trigone. The localization of the trigone determinates the size of the azygos lobe (Caceres et al, 1993; Fuad & Mubarak, 2016 ). A Left azygos lobe has been reported, but it is extremely rare (Özdemir et al, 2017)

Diagnosis of the azygos lobe may be complicated by morphologic variants of the fissure, physiological changes in the size of vein, and the projection of additional shadows within the lobe which may be misinterpreted as scar tissue, a calcified area of a post-infection process, or a malignant tissue or nodule.

 Lateral view, the arrow shows the location of the azygos lobe

Anterior view, the arrow shows the location of the azygos lobe
Images provided by the authors.  Click on the image for a larger depiction

It usually has no clinical implications and is an incidental finding in images but the azygos vein may undergo physiological variations, reflected by changes in the size of its shadow and its position in the imaging studies. Expiration, the Valsalva maneuver, or the upright position effect on the venous return to the heart, may enhance the size of the vein and its shadow. Changes in intrathoracic pressure may result in the “empty azygos fissure” phenomenon, in which the medial displacement of the azygos vein occurs after the reexpansion of the collapsed lung, secondary to pneumothorax or pleural effusion as well as a shortened mesoazygos.

In rare cases the azygos veins may undergo variceal changes that are usually located in the arc of the vein. They remained asymptomatic or may be accompanied by a “pressure like” or “tightness” sensation within the chest, recurrent hemoptysis with bright red blood dry cough and dyspnea. The initial differential diagnosis includes acute myocardial infarction, aortic dissection and myocarditis. On the chest X-ray it may present as a round or oval paratracheal shadow with a smooth surface or outline. Untreated, it may predispose the patient to the risk of rupture, thrombosis, or pulmonary embolism. Azygos thrombosis is extremely rare and most cases in the literature had an undelaying azygos dilation or some prothrombotic status like malignancy. In all lung tissue some pathological process can originate in the azygos lobe as bullous, bronchiectatic changes, pneumonia and tuberculosis. (Kotov et al, 2018; Denega et al, 2015)

Otherwise, it seems the mesoazygos fold serve as a barrier to dissemination of the infection or malignant cells.

For thoracoscopic procedures, recognition of the azygos lobe is particularly important as it can cause partial obstruction of the surgical site view during thoracoscopic sympathectomy. In the literature, two cases have been reported where the phrenic nerve was coursing within the azygos fissure (Kauffman et al, 2010; Pradhan, 2017; Özdemir et al, 2017; Paul, Siba & James, 2018)

Thoracic surgeons as well as treating physicians need to be aware of this rare anatomical variation.

NOTE: For an explanation of the etymology of the word "azygos" click here.

Sources:

1. Akhtar, Jamal & Lal, Amos & B. Martin, Kevin & Popkin, Joel. (2018). Azygos lobe: A rare cause of right paratracheal opacity. Respiratory Medicine Case Reports. 23. 10.1016/j.rmcr.2018.02.001.
2. Caceres, Jennelyn & Mata, Jonathan & Alegret, X & Palmer, J & Franquet, T. (1993). Increased density of the azygos lobe on frontal chest radiographs simulating disease: CT findings in seven patients. AJR. American journal of roentgenology. 160. 245-8. 10.2214/ajr.160.2.8424325.
3. Denega T, Alkul S, Islam E, Alalawi R. (2015). Recurrent hemoptysis - a complication associated with an azygos lobe. The Southwest Respiratory and Critical Care Chronicles, [S.l.], v. 3, n. 11, p. 44-47. ISSN 2325-9205.
4. Fuad, A.R., & Mubarak (2016). Two Cases of Azygos Lobe with Normal and Aneurysmal Azygos Vein on Computed Tomography. Int J Anat Res 2016, Vol 4(1):1843-45. ISSN 2321-4287
5. Kauffman, Paulo & Wolosker, Nelson & De Campos, José Ribas & Yazbek, Guilherme & Biscegli Jatene, Fábio. (2010). Azygos Lobe: A Difficulty in Video-Assisted Thoracic Sympathectomy. The Annals of thoracic surgery. 89. e57-9. 10.1016/j.athoracsur.2010.03.030.
6.Kotov G, Dimitrova I N, Iliev A, et al. (2018). A Rare Case of an Azygos Lobe in the Right Lung of a 40-year-old Male. Cureus 10(6): e2780. doi:10.7759/cureus.2780