Medical Terminology Daily (MTD) is a blog sponsored by Clinical Anatomy Associates, Inc. as a service to the medical community. We post anatomical, medical or surgical terms, their meaning and usage, as well as biographical notes on anatomists, surgeons, and researchers through the ages. Be warned that some of the images used depict human anatomical specimens.

You are welcome to submit questions and suggestions using our "Contact Us" form. The information on this blog follows the terms on our "Privacy and Security Statement" and cannot be construed as medical guidance or instructions for treatment.


We have 179 guests online


A Moment in History

Jean-Louis Petit

Jean Louis Petit
(1674 – 1750)

French surgeon and anatomist, Jean Louis Petit was born in Paris in on March 13, 1674.  His family rented an apartment at his house to Alexis Littre (1658 – 1726), a French anatomist. Petit became an apprentice of Littre at seven years of age, helping him in the dissections for his lectures and at an early age became the assistant in charge of the anatomic amphitheater.

Because of Petit’s dedication to anatomy and medicine, in 1690 at the age of sixteen, became a disciple of a famous Paris surgeon, Castel.

In 1692, Petit entered the French army and performed surgery in two military campaigns. By 1693 he started delivering lectures and was accepted as a great surgeon, being invited to the most difficult operations.  In 1700 he was appointed Chief Surgeon of the Military School in Paris and in the same year he received the degree of Master of Surgery from the Faculty of Paris.

In 1715 he was made a member of the Royal Academy of Sciences and an honorary member of the Royal Society of London. He was appointed by the King as the first Director General of the Royal Academy of Surgery when it was founded in 1731.

Petit’s written works are of historical importance.  “Traite des Maladies des Os” ( A Treatise on Bone Diseases);  “Traite des Maladies Chirurgicales et des Operation” (A Treatise on Surgical Diseases and their Operations” This last book was published posthumously in 1774. He also published a monograph on hemorrhage, another on lachrymal fistula, and others.

He was one of the first to perform choIecystotomy and mastoidotomy. His original tourniquet design for amputations saved many in the battlefield and the design of the same surgical instrument today has not changed much since its invention by him.

His name is remembered in the lumbar triangle, also called the "triangle of Petit", and the abdominal hernia that can ensue through that area of weakness, the lumbar hernia or "Petit's hernia".

Sources:
1. “Jean Louis Petit – A Sketch of his Life, Character, and Writings” Hayne, AP San Fran Western Lancet 1875 4: 446-454
2. “Oeuvres compl?tes de Jean-Louis Petit” 1837 Imprimerie de F. Chapoulaud
3. Extraits de l'eloge de Jean-Louis Petit Ius dans Ia seance publique de I' Academie royale de chirurgie du 26 mai 1750” Louis A. Chirurgie 2001: 126 : 475- 81


 "Clinical Anatomy Associates, Inc., and the contributors of "Medical Terminology Daily" wish to thank all individuals who donate their bodies and tissues for the advancement of education and research”.

Click here for more information


abebooks banner

bookplateink.com

 

 

Sinus of Valsalva

The sinuses of Valsalva are dilations related to both the aortic root of the ascending aorta and the root of the pulmonary trunk. These sinuses form part of the functional aspect of the corresponding aortic valve and pulmonary valve. Each one of these semilunar valves presents normally with three sinuses of Valsalva, although the sinuses of the pulmonary valve are smaller than those of the aortic valve.

One of the problems encountered when describing each sinus of Valsalva is the fact that the sinus itself is not a structure, but a space. This space is found between the corresponding valve leaflet (or cusp) and the arterial wall which presents with a concavity, thus creating the sinus. This concavity is important functionally as it allows the leaflet to “flutter” in the arterial stream without getting stuck to the arterial wall. Physiological studies on the presence of the sinuses of Valsalva indicate that they play an important role decreasing of minimizing the stress of the valve leaflets.

Aortic root of the ascending aorta open by dissection
Aortic root open. Click on the image for a larger version.
The dilation of the sinuses of Valsalva also creates a bulbous region at the origin of both the ascending aorta and the pulmonary trunk, the “root” of these arteries.  For a better view of this bulbous region, click here. The boundary between the bulbous sinusal segment and the tubular segment of the arteries is known as the sinotubular junction (STJ).

The accompanying image shows a human ascending aorta that has been cut open to show the sinuses of Valsalva (yellow arrows), and the three cusps (leaflets) of the aortic valve. These are the non-coronary cusp (NCC), right coronary cusp (RCC), and the left coronary cusp (LCC). The ostia of the coronary arteries are visible inferior to the STJ.

The sinuses of Valsalva are named after Antonio Maria Valsalva (1666 - 1723), an Italian physician and anatomist.

Sources:
1. “Anatomy of the aortic root: implications for valve sparing surgery” Charitos EI, Sieveres, HH Ann Cardiothorac Surg 2013;2(1):53-56
2. “Clinical Anatomy of the Aortic Root” Anderson, RH Heart 200; 84: 670–673
3. “The Anatomy of the Aortic Root” Loukas, E et al. Clin Anat 2014; 27:748-756
4: "Stress Analysis of the Aortic Valve With and Without the Sinuses of Valsalva" Beck, A et al J Heart Dis 2001; 10 (1) 1-11
Image property of: CAA.Inc.Photographer: D.M. Klein 

MTD Main Page Back to MTD Main Page