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 The pons (from Latin , "bridge") is part of the brainstem that in humans and other bipeds lies inferior to the midbrain, superior to the medulla oblongata and anterior to the cerebellum. The pons is also called the pons Varolii ("bridge of Va ...

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

Henri Duret Henri Duret (7 July 1849, Condé-sur-Noireau – 7 April 1921) was a French neurologist whose contributions to the knowledge of cerebral circulation and the physiology of the brainstem were important for the early years of brain surgery. For thir ...

Causes

Duret haemorrhages are named after

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

and upper

of the brainstem. They are caused by a traumatic downward displacement of the brainstem with parahippocampal gyrus herniation through the tentorial notch. or acute hematoma, edema 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 i ...

, abscess, 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 mmHg for a supine adult ...

with formation of a transtentorial pressure cone involving the front part of the cerebral peduncles, the cerebral crura. Increased pressure above the tentorium may also involve other midbrain structures. Kernohan's notch 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 tract ...

which may be caused by this displacement of the brainstem against the tentorial incisure. The resulting ipsilateral

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

is a false localising sign, known as the ''Kernohan-Woltman syndrome''. This may succeed or accompany temporal lobe (uncal)

herniation A hernia is the abnormal exit of tissue or an organ, such as the bowel, through the wall of the cavity in which it normally resides. Various types of hernias can occur, most commonly involving the abdomen, and specifically the groin. Groin hernia ...

and subfalcian herniation secondary to a

supratentorial In anatomy, the supratentorial region of the brain is the area located above the tentorium cerebelli. The area of the brain below the tentorium cerebelli is the infratentorial region. The supratentorial region contains the cerebrum, while the infr ...

mass. The pathophysiological mechanism is uncertain but is probably caused by the displacement of the brainstem 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 th ...

may play a role.

Diagnosis

Duret haemorrhages can be demonstrated by medical imaging techniques of CT or

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

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 ...

. 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