Degeneration (medical)

Last updated

Degeneration is deterioration in the medical sense. Generally, it is the change from a higher to a lower form. More specifically, it is the change of tissue to a lower or less functionally active form.

See also

Related Research Articles

Wilsons disease Genetic multisystem copper-transport disease

Wilson's disease is a genetic disorder in which excess copper builds up in the body. Symptoms are typically related to the brain and liver. Liver-related symptoms include vomiting, weakness, fluid build up in the abdomen, swelling of the legs, yellowish skin and itchiness. Brain-related symptoms include tremors, muscle stiffness, trouble speaking, personality changes, anxiety, and psychosis.

Edema Accumulation of fluid in body tissue

Edema, also spelt oedema, and also known as fluid retention, dropsy, hydropsy and swelling, is the build-up of fluid in the body's tissue. Most commonly, the legs or arms are affected. Symptoms may include skin which feels tight, the area may feel heavy, and affected joints may be hard to move. Other symptoms depend on the underlying cause.

Intervertebral disc Cartilage of spine

An intervertebral disc lies between adjacent vertebrae in the vertebral column. Each disc forms a fibrocartilaginous joint, to allow slight movement of the vertebrae, to act as a ligament to hold the vertebrae together, and to function as a shock absorber for the spine.

Connective tissue Type of biological tissue

Connective tissue is one of the four basic types of animal tissue, along with epithelial tissue, muscle tissue, and nervous tissue. It develops from the mesoderm. Connective tissue is found in between other tissues everywhere in the body, including the nervous system. In the central nervous system, the three outer membranes that envelop the brain and spinal cord are composed of connective tissue. All connective tissue consists of three main components: fibers, ground substance and cells. Not all authorities include blood or lymph as connective tissue because they lack the fiber component. All are immersed in the body water. The cells of connective tissue include fibroblasts, adipocytes, macrophages, mast cells and leucocytes.

Gangrene Type of tissue death by a lack of blood supply

Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the gangrene is caused by an infectious agent it may present with a fever or sepsis.

Retinoschisis Eye disease involving splitting of the retina

Retinoschisis is an eye disease characterized by the abnormal splitting of the retina's neurosensory layers, usually in the outer plexiform layer. Retinoschisis can be divided into degenerative forms which are very common and almost exclusively involve the peripheral retina and hereditary forms which are rare and involve the central retina as sometimes the peripheral retina. The degenerative forms are asymptomatic and involve the peripheral retina only and do not affect the visual acuity. Some rarer forms result in a loss of vision in the corresponding visual field.

Carboxyhemoglobin

Carboxyhemoglobin or carboxyhaemoglobin (symbol COHb or HbCO) is a stable complex of carbon monoxide and hemoglobin (Hb) that forms in red blood cells upon contact with carbon monoxide (CO). Carboxyhemoglobin is often mistaken for the compound formed by the combination of carbon dioxide and hemoglobin, which is actually carbaminohemoglobin. Exposure to small concentrations of CO hinder the ability of Hb to deliver oxygen to the body, because carboxyhemoglobin forms more readily than does oxyhemoglobin (HbO2). CO is produced in normal metabolism and is also a common chemical. Tobacco smoking (through carbon monoxide inhalation) raises the blood levels of COHb by a factor of several times from its normal concentrations.

Diverticulosis Condition of having diverticula (outpocketings) in the wall of the intestine

Diverticulosis is the condition of having multiple pouches (diverticula) in the colon that are not inflamed. These are outpockets of the colonic mucosa and submucosa through weaknesses of muscle layers in the colon wall, and may be due in part to low-fiber diet prompting changes in intestinal microflora with consequent low-grade inflammation. Diverticula don't cause symptoms in most people. Diverticular disease occurs when diverticula become clinically inflamed, a condition known as diverticulitis.

Osteophyte

Osteophytes are exostoses that form along joint margins. They should not be confused with enthesophytes, which are bony projections that form at the attachment of a tendon or ligament. Osteophytes are not always distinguished from exostoses in any definite way, although in many cases there are a number of differences. Osteophytes are typically intra-articular.

Macular degeneration Medical condition associated with vision loss

Macular degeneration, also known as age-related macular degeneration, is a medical condition which may result in blurred or no vision in the center of the visual field. Early on there are often no symptoms. Over time, however, some people experience a gradual worsening of vision that may affect one or both eyes. While it does not result in complete blindness, loss of central vision can make it hard to recognize faces, drive, read, or perform other activities of daily life. Visual hallucinations may also occur but these do not represent a mental illness.

Degenerative disc disease

Degenerative disc disease (DDD) is a medical condition in which there are anatomic changes and a loss of function of varying degrees of one or more intervertebral discs of the spine of sufficient magnitude as to cause symptoms. The root cause is thought to be loss of soluble proteins within the fluid contained in the disc with resultant reduction of the oncotic pressure, which in turn causes loss of fluid volume. Normal downward forces cause the affected disc to lose height, and the distance between vertebrae is reduced. The anulus fibrosus, the rigid outer shell of a disc, also weakens. This loss of height causes laxity of the longitudinal ligaments, which may allow anterior, posterior, or lateral shifting of the vertebral bodies, causing facet joint malalignment and arthritis; scoliosis; cervical hyperlordosis; thoracic hyperkyphosis; lumbar hyperlordosis; narrowing of the space available for the spinal tract within the vertebra ; or narrowing of the space through which a spinal nerve exits with resultant inflammation and impingement of a spinal nerve, causing a radiculopathy.

Caseous necrosis

Caseous necrosis or caseous degeneration is a unique form of cell death in which the tissue maintains a cheese-like appearance. It is also a distinctive form of coagulative necrosis. The dead tissue appears as a soft and white proteinaceous dead cell mass.

Batten disease is a fatal disease of the nervous system that typically begins in childhood. Onset of symptoms is usually between 5 and 10 years of age. Often, it is autosomal recessive. It is the common name for a group of disorders called the neuronal ceroid lipofuscinoses (NCLs).

Pneumonitis

Pneumonitis describes general inflammation of lung tissue. Possible causative agents include radiation therapy of the chest, exposure to medications used during chemo-therapy, the inhalation of debris, aspiration, herbicides or fluorocarbons and some systemic diseases. If unresolved, continued inflammation can result in irreparable damage such as pulmonary fibrosis.

Corticobasal degeneration (CBD) is a rare neurodegenerative disease involving the cerebral cortex and the basal ganglia. CBD symptoms typically begin in people from 50 to 70 years of age, and the average disease duration is six years. It is characterized by marked disorders in movement and cognition, and is classified as one of the Parkinson plus syndromes. Diagnosis is difficult, as symptoms are often similar to those of other disorders, such as Parkinson's disease, progressive supranuclear palsy, and dementia with Lewy bodies, and a definitive diagnosis of CBD can only be made upon neuropathologic examination.

Bradypnea is abnormally slow breathing. The respiratory rate at which bradypnea is diagnosed depends on the age of the person.

Tauopathy

Tauopathy belongs to a class of neurodegenerative diseases involving the aggregation of tau protein into neurofibrillary or gliofibrillary tangles (NFTs) in the human brain. Tangles are formed by hyperphosphorylation of the microtubule protein known as tau, causing the protein to dissociate from microtubules and form insoluble aggregates. The mechanism of tangle formation is not well understood, and whether tangles are a primary cause of Alzheimer's disease or play a peripheral role is unknown.

Progressive muscular atrophy

Progressive muscular atrophy (PMA) is a very rare subtype of motor neuron disease (MND) that affects only the lower motor neurons. PMA is thought to account for around 4% of all MND cases. This is in contrast to amyotrophic lateral sclerosis (ALS), the most common form of MND, which affects both the upper and lower motor neurons, or primary lateral sclerosis, another rare MND variant, which affects only the upper motor neurons. The distinction is important because PMA is associated with a better prognosis than classic ALS.

Spinal disc herniation Disease

Spinal disc herniation is an injury to the cushioning and connective tissue between vertebrae, usually caused by excessive strain or trauma to the spine. It may result in back pain, pain or sensation in different parts of the body, and physical disability. The most conclusive diagnostic tool for disc herniation is MRI, and treatment may range from painkillers to surgery. Protection from disc herniation is best provided by core strength and an awareness of body mechanics including posture.

Central nervous system disease Disease of the brain or spinal cord

Central nervous system diseases, also known as central nervous system disorders, are a group of neurological disorders that affect the structure or function of the brain or spinal cord, which collectively form the central nervous system (CNS).

References

Dorland's Illustrated Medical Dictionary (Twenty-sixth Edition) ( ISBN   0-7216-1645-3)