François Pourfour du Petit (24 June 1664 – 18 June 1741) was a French

anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its ...

ophthalmologist Ophthalmology ( ) is a surgery, surgical subspecialty within medicine that deals with the diagnosis and treatment of eye disorders. An ophthalmologist is a physician who undergoes subspecialty training in medical and surgical eye care. Followin ...

and

surgeon In modern medicine, a surgeon is a medical professional who performs surgery. Although there are different traditions in different times and places, a modern surgeon usually is also a licensed physician or received the same medical training as ...

who conducted careful anatomical studies of the human eye. He also conducted early experiments in neurology. Petit was born in

Paris Paris () is the capital and most populous city of France, with an estimated population of 2,165,423 residents in 2019 in an area of more than 105 km² (41 sq mi), making it the 30th most densely populated city in the world in 2020. S ...

and was orphaned at an early age. He studied the classics at the College de Beauvais before studies in Belgium and Germany. He then studied medicine at the

University of Montpellier The University of Montpellier (french: Université de Montpellier) is a public university, public research university located in Montpellier, in south-east of France. Established in 1220, the University of Montpellier is one of the oldest univ ...

, and afterwards

surgery Surgery ''cheirourgikē'' (composed of χείρ, "hand", and ἔργον, "work"), via la, chirurgiae, meaning "hand work". is a medical specialty that uses operative manual and instrumental techniques on a person to investigate or treat a pat ...

at the

Hôpital de la Charité Hôpital de la Charité (, "Charity Hospital") was a hospital in Paris founded in the 17th century and closed in 1935. History In 1606, Marie de Médicis invited the Brothers Hospitallers of St. John of God to come to France. The Abbot of Sain ...

in Paris. During this period of time he also attended lectures by

Guichard Joseph Duverney Joseph Guichard Duverney or Joseph-Guichard Du Verney (5 August 1648 – 10 September 1730) was a French anatomist known for his work in comparative anatomy and for his treatise on the ear. The fracture of the iliac wing of the pelvis is some ...

(1648–1730) in anatomy and

Joseph Pitton de Tournefort Joseph Pitton de Tournefort (5 June 165628 December 1708) was a French botanist, notable as the first to make a clear definition of the concept of genus for plants. Botanist Charles Plumier was his pupil and accompanied him on his voyages. Lif ...

(1656–1708) in

botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the Ancient Greek w ...

. Between 1693 and 1713 he was a military physician in the armies of

Louis XIV , house = Bourbon , father = Louis XIII , mother = Anne of Austria , birth_date = , birth_place = Château de Saint-Germain-en-Laye, Saint-Germain-en-Laye, France , death_date = , death_place = Palace of Vers ...

, and after the

Peace of Utrecht The Peace of Utrecht was a series of peace treaties signed by the belligerents in the War of the Spanish Succession, in the Dutch city of Utrecht between April 1713 and February 1715. The war involved three contenders for the vacant throne of ...

(1713), he returned to Paris as an eye specialist. He conducted many cataract surgeries using the technique of displacing the lens using a needle and influenced Jacques Daviel approach to cataract treatment. He made careful measurements and used biometrical approaches to understanding the eye. He was among the first to note changes in the shape of the lens with age. From 1722 to 1741 he was a member of the

Académie Royale des Sciences The French Academy of Sciences (French: ''Académie des sciences'') is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the ...

: associate member chemist and anatomist in 1722, then resident member anatomist in 1725. Petit is remembered for his detailed anatomical studies of the eye, as well as

physiological Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a sub-discipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out the chemical ...

research of the

sympathetic nervous system The sympathetic nervous system (SNS) is one of the three divisions of the autonomic nervous system, the others being the parasympathetic nervous system and the enteric nervous system. The enteric nervous system is sometimes considered part of th ...

. As a military physician, Petit noticed that there was a striking correlation between soldiers' head wounds and

contralateral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

motor effects, which he documented in a 1710 treatise called ''Lettres d’un medecin des hopitaux du roi a un autre medecin de ses amis''. He was able to conduct ablations in dogs and produce similar effects. He performed pioneer investigations on the internal structure of the

spinal cord The spinal cord is a long, thin, tubular structure made up of nervous tissue, which extends from the medulla oblongata in the brainstem to the lumbar region of the vertebral column (backbone). The backbone encloses the central canal of the spi ...

, and gave an early, detailed description of the

decussation of the pyramids In neuroanatomy, the medullary pyramids are paired white matter structures of the brainstem's medulla oblongata that contain motor fibers of the corticospinal and corticobulbar tracts – known together as the pyramidal tracts. The lower limit o ...

. He also provided the first clinical description of symptoms of the rare Pourfour du Petit syndrome, which is thought to be closely related to

Horner's syndrome Horner's syndrome, also known as oculosympathetic paresis, is a combination of symptoms that arises when a group of nerves known as the sympathetic trunk is damaged. The signs and symptoms occur on the same side (ipsilateral) as it is a lesion o ...

, and also known as reverse Horner syndrome because of its clinical features of mydriasis, eyelid retraction and hyperhidrosis.

Associated eponyms

Anatomical features named after Petit include:Who Named It; François Pourfour du Petit
(biographical information and eponyms) * ''Petit's canals'': Also known as ''spatia zonularia'',

lymph Lymph (from Latin, , meaning "water") is the fluid that flows through the lymphatic system, a system composed of lymph vessels (channels) and intervening lymph nodes whose function, like the venous system, is to return fluid from the tissues to ...

-filled spaces between the fibers of the

ciliary zonule The zonule of Zinn () (Zinn's membrane, ciliary zonule) (after Johann Gottfried Zinn) is a ring of fibrous strands forming a zonule (little band) that connects the ciliary body with the crystalline lens of the eye. These fibers are sometimes colle ...

at the equator of the

lens A lens is a transmissive optical device which focuses or disperses a light beam by means of refraction. A simple lens consists of a single piece of transparent material, while a compound lens consists of several simple lenses (''elements''), ...

of the eye. * ''Petit's sinuses'': Also known as

aortic sinus An aortic sinus, also known as a sinus of Valsalva, is one of the anatomic dilations of the ascending aorta, which occurs just above the aortic valve. These widenings are between the wall of the aorta and each of the three cusps of the aortic val ...

es, the space between each

semilunar valve A heart valve is a one-way valve that allows blood to flow in one direction through the chambers of the heart. Four valves are usually present in a mammalian heart and together they determine the pathway of blood flow through the heart. A heart v ...

and the wall of the

aorta The aorta ( ) is the main and largest artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries (the common iliac arteries). The aorta distributes ...

References

French ophthalmologists French anatomists Members of the French Academy of Sciences 1664 births 1741 deaths {{France-med-bio-stub