Cerebral softening, also known as encephalomalacia, is a localized softening of the substance of the

brain A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a ve ...

, due to

bleeding Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...

inflammation Inflammation (from la, inflammatio) is part of the complex biological response of body tissues to harmful stimuli, such as pathogens, damaged cells, or irritants, and is a protective response involving immune cells, blood vessels, and molec ...

. Three varieties, distinguished by their color and representing different stages of the disease progress, are known respectively as red, yellow, and white softening.

Causes

Stroke

Ischemia: A decreased or restriction of circulating blood flow to a region of the brain which deprives neurons of the necessary substrates (primarily

glucose Glucose is a simple sugar with the molecular formula . Glucose is overall the most abundant monosaccharide, a subcategory of carbohydrates. Glucose is mainly made by plants and most algae during photosynthesis from water and carbon dioxide, u ...

); represents 80% of all strokes. A

thrombus A thrombus (plural thrombi), colloquially called a blood clot, is the final product of the blood coagulation step in hemostasis. There are two components to a thrombus: aggregated platelets and red blood cells that form a plug, and a mesh of ...

embolus An embolus (; plural emboli; from the Greek ἔμβολος "wedge", "plug") is an unattached mass that travels through the bloodstream and is capable of creating blockages. When an embolus occludes a blood vessel, it is called an embolism or emb ...

plugs an artery so there is a reduction or cessation of blood flow. This hypoxia or anoxia leads to neuronal injury, which is known as a stroke. The death of neurons leads to a so-called softening of the

cerebrum The cerebrum, telencephalon or endbrain is the largest part of the brain containing the cerebral cortex (of the two cerebral hemispheres), as well as several subcortical structures, including the hippocampus, basal ganglia, and olfactory bulb ...

in the affected area. Hemorrhage: Intracerebral hemorrhage occurs in deep penetrating vessels and disrupts the connecting pathways, causing a localized pressure injury and in turn injury to brain tissue in the affected area.

Hemorrhaging Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, vag ...

can occur in instances of embolic ischemia, in which the previously obstructed region spontaneously restores blood flow. This is known as a hemorrhagic infarction and a resulting red infarct occurs, which points to a type of cerebral softening known as red softening.Shah, Sid. "Stroke Pathophysiology." Foundation for Education and Research in Neurological Emergencies. 1-7. http://www.uic. edu/com/ferne/pdf/pathophys0501.pdf.

Circle of Willis

In a study on the

circle of Willis The circle of Willis (also called Willis' circle, loop of Willis, cerebral arterial circle, and Willis polygon) is a circulatory anastomosis that supplies blood to the brain and surrounding structures in reptiles, birds and mammals, including huma ...

and its relation to cerebral vascular disorders, a comparison on various anomalies between normal brains (those without the condition of cerebral softening) and brains with cerebral softening were looked at to observe trends in the differences of the anatomical structure of the circle of Willis. Statistically significant results were found in the percentage of normal brains that had a normal circle of Willis and those that had cerebral softening and had a normal circle of Willis. The results yielded 52% of normal brains having a normal circle of Willis, while only 33% of brains with cerebral softening had a normal circle of Willis. There were also a higher number of string-like vessels in brains with cerebral softening (42%), than there were in normal brains (27%). These results point to an assumption of a higher incidence rate of anomalies in brains with cerebral softening versus those that do not have cerebral softening.

Types of softening

Red softening

Red softening is one of the three types of cerebral softening. As its name suggests, certain regions of cerebral softening result in a red color. This is due to a hemorrhagic infarct, in which blood flow is restored to an area of the brain that was previously restricted by an

embolism An embolism is the lodging of an embolus, a blockage-causing piece of material, inside a blood vessel. The embolus may be a blood clot (thrombus), a fat globule (fat embolism), a bubble of air or other gas ( gas embolism), amniotic fluid (am ...

. This is termed a "red infarct" or also known as red softening. Upon autopsy of several subjects, Dr. Cornelio Fazio found that the most common areas of this type of softening occurred where there was a

hemorrhage Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethra, v ...

of the middle

cerebral artery The cerebral arteries describe three main pairs of arteries and their branches, which perfuse the cerebrum of the brain. The three main arteries are the: * '' Anterior cerebral artery'' (ACA) * ''Middle cerebral artery'' (MCA) * ''Posterior cere ...

or the superior or deep branches to it. The subjects' softened area was not always near the arteries but where the capillaries perfused the brain tissue. The symptoms were similar to that of a stroke.

White softening

White softening is another form of cerebral softening. This type of softening occurs in areas that continue to be poorly perfused, with little to no blood flow. These are known as "pale" or "anemic infarcts" and are areas that contain dead neuronal tissue, which result in a softening of the cerebrum.

Yellow softening

Yellow softening is the third type of cerebral softening. As its name implies, the affected softened areas of the brain have a yellow appearance. This yellow appearance is due to

atherosclerotic plaque An atheroma, or atheromatous plaque, is an abnormal and reversible accumulation of material in the inner layer of an arterial wall. The material consists of mostly macrophage cells, or debris, containing lipids, calcium and a variable amount ...

build-up in interior brain arteries coupled with yellow lymph around the

choroid plexus The choroid plexus, or plica choroidea, is a plexus of cells that arises from the tela choroidea in each of the ventricles of the brain. Regions of the choroid plexus produce and secrete most of the cerebrospinal fluid (CSF) of the central nerv ...

, which occurs in specific instances of brain trauma.Br Med J 1898;1:140

Stages

Early life

Newborn cerebral softening has traditionally been attributed to trauma at birth and its effect on brain tissue into adulthood. However, more recent research shows that cerebral softening in newborns and the degeneration of

white matter White matter refers to areas of the central nervous system (CNS) that are mainly made up of myelinated axons, also called tracts. Long thought to be passive tissue, white matter affects learning and brain functions, modulating the distributi ...

is caused by

asphyxia Asphyxia or asphyxiation is a condition of deficient supply of oxygen to the body which arises from abnormal breathing. Asphyxia causes generalized hypoxia, which affects primarily the tissues and organs. There are many circumstances that ca ...

and/or later infection. There is no causal evidence to support the hypothesis that problems in labor contribute to the development of softening in infant white matter. Also, further evidence shows a possible connection between low sugar and high protein levels in

cerebral spinal fluid Cerebrospinal fluid (CSF) is a clear, colorless body fluid found within the tissue that surrounds the brain and spinal cord of all vertebrates. CSF is produced by specialised ependymal cells in the choroid plexus of the ventricles of the br ...

that can contribute to disease or virus susceptibility leading to cerebral softening.

Later life

Cases of cerebral softening in infancy versus in adulthood are much more severe due to an infant's inability to sufficiently recover brain tissue loss or compensate the loss with other parts of the brain. Adults can more easily compensate and correct for the loss of tissue use and therefore the mortality likelihood in an adult with cerebral softening is less than in an infant.

Documented cases

In this late 19th-century case study, a 10-year-old boy was found to have cerebral softening in specific parts of the brain, limiting specific sensory function. The identifiable softening enabled researchers to detect and partition cerebral areas related to different sensory perceptions. Another case in the late 19th century showed that cerebral softening, when caused by hemorrhaging, can affect various neural pathways leading to

convulsions A convulsion is a medical condition where the body muscles contract and relax rapidly and repeatedly, resulting in uncontrolled shaking. Because epileptic seizures typically include convulsions, the term ''convulsion'' is sometimes used as a s ...

spasm A spasm is a sudden involuntary contraction of a muscle, a group of muscles, or a hollow organ such as the bladder. A spasmodic muscle contraction may be caused by many medical conditions, including dystonia. Most commonly, it is a muscle c ...

s, coma and death. A third case in 1898 followed the ten-day decline of a 66-year-old woman with cerebral softening. She had yellow softening which led to symptoms that started slowly with transient facial paralysis on the right side of the face. The limbs later became cold and the right side of the body transiently progressed between semi-paralysis and

tetanus Tetanus, also known as lockjaw, is a bacterial infection caused by ''Clostridium tetani'', and is characterized by muscle spasms. In the most common type, the spasms begin in the jaw and then progress to the rest of the body. Each spasm usually ...

. Her heart rate and respiration rate became slow by days three and four. Later she developed a yellow jaundiced appearance in the sclera and skin that the doctor proposed as paroxysmal hemoglobinuria upon autopsy. On the last days, the paralysis became more frequent, respiration rose and she developed

tachycardia Tachycardia, also called tachyarrhythmia, is a heart rate that exceeds the normal resting rate. In general, a resting heart rate over 100 beats per minute is accepted as tachycardia in adults. Heart rates above the resting rate may be normal ( ...

. She died on the evening of the tenth day. The autopsy revealed that the top of the brain down to the

lateral ventricle The lateral ventricles are the two largest ventricles of the brain and contain cerebrospinal fluid (CSF). Each cerebral hemisphere contains a lateral ventricle, known as the left or right ventricle, respectively. Each lateral ventricle resemble ...

were healthy, but below that there was a inch area on the left side of the brain that was softened and yellow. The

was also matted and surrounded by vessels filled with yellow lymph. The floor of the left lateral ventricle,

thalamus The thalamus (from Greek θάλαμος, "chamber") is a large mass of gray matter located in the dorsal part of the diencephalon (a division of the forebrain). Nerve fibers project out of the thalamus to the cerebral cortex in all directions, ...

, and

corpus striatum The striatum, or corpus striatum (also called the striate nucleus), is a nucleus (a cluster of neurons) in the subcortical basal ganglia of the forebrain. The striatum is a critical component of the motor and reward systems; receives glutamat ...

were softened to the point of unrecognition. These physical abnormalities match the symptoms mentioned and are a prime example of yellow cerebral softening. In 1858 doctor Thomas Inman described four of thirty discovered cases with cerebral softening. Each case was similar to the previous article. There was some

atheroma An atheroma, or atheromatous plaque, is an abnormal and reversible accumulation of material in the inner layer of an arterial wall. The material consists of mostly macrophage cells, or debris, containing lipids, calcium and a variable amount o ...

in the internal brain arteries that led to the cerebral softening of the left side of the brain around the left

and

. There were similar right sided numbness in some patients, coldness of the extremities, and impairments in vision. In some cases, the lungs and the

pleura The pulmonary pleurae (''sing.'' pleura) are the two opposing layers of serous membrane overlying the lungs and the inside of the surrounding chest walls. The inner pleura, called the visceral pleura, covers the surface of each lung and dips b ...

were stuck together as well as the intestines to the peritoneal wall. This again matches yellow cerebral softening.

References

{{Medical resources , DiseasesDB = , ICD10 = , ICD9 = {{ICD9, 348.89 , ICDO = , OMIM = , MedlinePlus = , eMedicineSubj = , eMedicineTopic = , MeshID = D004678 Brain disorders