Duret haemorrhages are small linear areas of bleeding in the

midbrain The midbrain or mesencephalon is the forward-most portion of the brainstem and is associated with vision, hearing, motor control, sleep and wakefulness, arousal (alertness), and temperature regulation. The name comes from the Greek ''mesos'', " ...

and upper pons of the

brainstem The brainstem (or brain stem) is the posterior stalk-like part of the brain that connects the cerebrum with the spinal cord. In the human brain the brainstem is composed of the midbrain, the pons, and the medulla oblongata. The midbrain is cont ...

. They are caused by a traumatic downward displacement of the brainstem. They are named after Henri Duret.

Causes

Duret haemorrhages are named after Henri Duret, who discovered these brainstem lesions in dogs with increased intracranial pressure. They are small linear areas of bleeding in the

and upper pons of the

. They are caused by a traumatic downward displacement of the brainstem with parahippocampal gyrus herniation through the

tentorial notch The tentorial notch (also known as the tentorial incisure or incisura tentorii) refers to the anterior opening between the free edge of the cerebellar tentorium and the Clivus (anatomy), clivus for the passage of the brainstem. The midbrain cont ...

. or acute

hematoma A hematoma, also spelled haematoma, or blood suffusion is a localized bleeding outside of blood vessels, due to either disease or trauma including injury or surgery and may involve blood continuing to seep from broken capillary, capillaries. A he ...

edema Edema, also spelled oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's Tissue (biology), tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels t ...

following

trauma Trauma most often refers to: *Major trauma, in physical medicine, severe physical injury caused by an external source *Psychological trauma, a type of damage to the psyche that occurs as a result of a severely distressing event *Traumatic inju ...

abscess An abscess is a collection of pus that has built up within the tissue of the body. Signs and symptoms of abscesses include redness, pain, warmth, and swelling. The swelling may feel fluid-filled when pressed. The area of redness often extends b ...

, or

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

Pathogenesis

Duret haemorrhages are haemorrhages secondary to raised

intracranial pressure Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 Millimeter of mercury, mmHg ...

with formation of a transtentorial pressure cone involving the front part of the cerebral peduncles, the cerebral crura. Increased pressure above the

tentorium The tentorium (plural tentoria) is a term used to refer to the framework of internal supports within an arthropod head. The tentorium is formed by ingrowths of the exoskeleton An exoskeleton (from Greek ''éxō'' "outer" and ''skeletós'' "sk ...

may also involve other midbrain structures.

Kernohan's notch Kernohan's notch is a cerebral peduncle indentation associated with some forms of transtentorial herniation (uncal herniation). It is a secondary condition caused by a primary injury on the ''opposite'' hemisphere of the brain.#refWolf, Wolf et al, ...

is a groove in the

cerebral peduncle The cerebral peduncles are the two stalks that attach the cerebrum to the brainstem. They are structures at the front of the midbrain which arise from the ventral pons and contain the large ascending (sensory) and descending (motor) nerve tra ...

which may be caused by this displacement of the

against the

tentorial incisure The tentorial notch (also known as the tentorial incisure or incisura tentorii) refers to the anterior opening between the free edge of the cerebellar tentorium and the Clivus (anatomy), clivus for the passage of the brainstem. The midbrain cont ...

. The resulting ipsilateral

hemiparesis Hemiparesis, or unilateral paresis, is weakness of one entire side of the body (''wikt:hemi-#Prefix, hemi-'' means "half"). Hemiplegia is, in its most severe form, complete paralysis of half of the body. Hemiparesis and hemiplegia can be caused ...

is a false localising sign, known as the ''Kernohan-Woltman syndrome''. This may succeed or accompany temporal lobe (uncal) herniation and subfalcian herniation secondary to a supratentorial mass. The pathophysiological mechanism is uncertain but is probably caused by the displacement of the

stretching and tearing perforating branches of the

basilar artery The basilar artery () is one of the arteries that supplies the brain with oxygen-rich blood. The two vertebral arteries and the basilar artery are known as the vertebral basilar system, which supplies blood to the posterior part of the circle of W ...

to the pons; venous

infarction Infarction is tissue death (necrosis) due to inadequate blood supply to the affected area. It may be caused by artery blockages, rupture, mechanical compression, or vasoconstriction. The resulting lesion is referred to as an infarct (from the ...

may play a role.

Diagnosis

Duret haemorrhages can be demonstrated by

medical imaging Medical imaging is the technique and process of imaging the interior of a body for clinical analysis and medical intervention, as well as visual representation of the function of some organs or tissues (physiology). Medical imaging seeks to rev ...

techniques of CT or MRI though difficult.

Prognosis

Duret haemorrhages usually indicate a fatal outcome. However, survival has been reported.

Society and culture

George Gershwin George Gershwin (; born Jacob Gershwine; September 26, 1898 – July 11, 1937) was an American composer and pianist whose compositions spanned popular, jazz and classical genres. Among his best-known works are the orchestral compositions ' ...

died after emergency surgery of a large brain tumour, believed to have been a

glioblastoma Glioblastoma, previously known as glioblastoma multiforme (GBM), is one of the most aggressive types of cancer that begin within the brain. Initially, signs and symptoms of glioblastoma are nonspecific. They may include headaches, personality ch ...

. The fact that he had suddenly collapsed and become comatose when he stood up on his last day of life, has been interpreted as brain herniation and Duret haemorrhages.Takahiro Mezaki
Gershwin's death and Duret haemorrhage
NEJM, 12 August 2017

References

External links

from MedPix {{Cerebrovascular diseases Cerebrovascular diseases