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A Moment in History

Dr. Thomas Dent Mütter
Dr. Thomas Dent Mütter (1811-1859)

Dr. Thomas Dent Mütter

(1811-1859)

Thomas Dent Mutter was born on March 9, 1811, in Richmond, VA. His mother died in 1813, and his father died of tuberculosis in 1817. Thomas was orphaned when he was barely 8 years old. His father left him a somewhat meager inheritance and in his early life had to do with less that others with his objectives in life. He was well educated under the tutelage of Robert Carter, his guardian, and in 1824 he started his studies at the Hampden Sidney College of Virginia. He continued with a medical apprenticeship with a Dr. Simms in VA. He was well respected and even at his early age he would do home visits for his medical benefactor with great results. He started medical studies at the University of Pennsylvania, where he earned his MD in 1831. The new young doctor, Thomas Dent Mutter, MD was only 20 years of age.

At the time, Europe was the place to go to if you wanted advanced medical studies. Dr. Mutter had no money, so he applied as a ship surgeon to be able to cross the Atlantic. Once in Europe, he spent time in Paris, where he studied under the tutelage of Dr. Guillaume Dupuytren. He later studied for a short time in England where he met Dr. Robert Liston. Following Dupuytren's teachings, Mutter was fascinated by plastic surgery.

A chance encounter with what was to become his first well-known acquisition of a medical curiosity, Mutter started thinking on how to help those people that were known at that time as “monsters”, patients who the general public did not see, because they did not appear in public. The curiosity in question was a wax reproduction of the face of a French woman who had a “horn” arising from her forehead. This piece is on exhibit at the Mütter Museum.

Back in the United States in 1832, Thomas Dent Mutter changed his last name to give it a more “European” sound and added an “umlaut”, so now he was Thomas D. Mütter, MD. It may also be that he wanted to pay homage to his Scottish-German heritage, who knows? He opened his medical office in Philadelphia and although it took time, eventually he had a thriving practice. One of his specialties was the work on “deformities” so common at the time because of facial scars born out of the use of open fires in houses, and deformities caused by burns and loss of tissue due to chemicals used in local industry. Dr. Mütter is the pioneer of what we call today “Reconstructive Surgery”.

In 1835 he was asked to join the Medical Institute of Philadelphia as an assistant professor of Surgery. He was an instant success. Dr. Mütter was adored by his students because, he would question the students and guide them to discovery instead of just lecturing and leaving. In his Discourse eulogy of Dr. Mütter by Joseph Pancoast he writes:” The power of attracting students near him by his mingled gentleness, energy, and enthusiasm; of fixing their attention by the lucid and methodical arrangements of his Subject, by his clear demonstrations, and sprightly oral elucidations, came so readily to him, and was so early displayed) as to seem almost intuitive.” In 1841 Dr Mütter was appointed Professor of Surgery at the Jefferson Medical College in Philadelphia.

Dr. Mütter had always had poor health, even in childhood, and his dedication to his passion, long hours, took its toll on his body. In 1956 he set sail for Europe and resigned his teaching duties. He was named Emeritus Professor of Surgery. Unfortunately, the trip did not help, and he returned to the US in early 1958. Fearful of another winter in cold Philadelphia, he moved to Charleston, SC, where he died on March 19, 1859.

Dr. Mütter’s story does not end here. He was an avid collector and throughout his short life he had pulled together an impressive collection of medical oddities, samples, and curiosities. Knowing that his life was at an end, he negotiated with the Philadelphia College of Physicians to have them host his collection in perpetuity as well as the creation of a trust fund that would ensure that the public and medical students would have access to this incredible collection. Through the years this collection has increased and is known today as the Mütter Museum of the Philadelphia College of Physicians. I strongly urge our readers to visit this incredible museum. For more information, click here.

Personal notes: In the late 90’s, I attended a meeting of the American Association of Clinical Anatomists.  During the meeting I met Gretchen Worden, who at the time was the Curator of the Mütter museum. Gretchen was inspirational, fun, and a great conversationalist! I had the opportunity to visit Gretchen at the Mütter museum and had the luck to be treated to a “behind the scenes” tour. What an experience! I was saddened to hear that Gretchen Worden passed on August 2, 2004. Still, in my recent visit to the Mütter Museum, I was glad to see a new section at the museum that remembers Gretchen. Her biography can be read here.

I would like to thank Dr. Leslie Wolf for lending me the book by O’Keefe that lead to me writing this article. Dr. Miranda

Sources:
1. “Dr. Mütter’s Marvels: A True Tale of Intrigue and Innovation at the Dawn of Modern Medicine” O’Keefe, C. 2015 Penguin Random House, LLC
2. “A Discourse Commemorative of the Late Professor T.D. Mütter” Pancoast, J. 1859 J Wilson Publisher
3. “Thomas Dent Mütter: the humble narrative of a surgeon, teacher, and curious collector” Baker, J, et al. The American Surgeon, Atlanta 77:iss5 662-14
4. “Thomas Dent Mutter, MD: early reparative surgeon” Harris, ES; Morgan, RF. Ann Plast Surg 1994 33(3):333-8
5. “5 Things I Learned from Thomas Dent Mütter” O’Keefe C.


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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