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Index of Diseases

Instructions. To find the proper medical term, scroll up and down to review the alphabetical listings. Also, you can use the "Page Up" and "Page down" key on your keyboard. Or use the search function of your browser. In both Netscape and Explorer, go to "Edit" and select "Find in Page". Type in the main term of interest. Frequently, it is best to type in only the first 4 or five letters (i.e., "prost" for prostate) because that will find more alternative terms from which to select the proper one.

I

Iatrogenic Disease

Definition: Any adverse condition in a patient occurring as the result of treatment by a physician, surgeon, or other health professional, especially infections acquired by the patient during the course of treatment.
Annotation: IM for general or as coord with specific iatrogenic dis; article must discuss dis as iatrogenic: do not routinely index adv eff of drugs or procedures as iatrogenic
ID#: D007049

Ichthyosiform Erythroderma, Congenital

Definition: Designation for several severe forms of ichthyosis, present at birth, that are characterized by hyperkeratotic scaling. Infants may be born encased in a collodion membrane which begins shedding within 24 hours. This is followed in about two weeks by persistent generalized scaling. The forms include bullous (HYPERKERATOSIS, EPIDERMOLYTIC), non-bullous (ICHTHYOSIS, LAMELLAR), wet type, and dry type.
Annotation: an ichthyosis rather than an erythroderma; do not use /congen & do not coord with INFANT, NEWBORN, DISEASES
ID#: D016113

Ichthyosis

Definition: Any of several generalized skin disorders characterized by dryness, roughness, and scaliness, due to hypertrophy of the stratum corneum epidermis. Most are genetic, but some are acquired, developing in association with other systemic disease or genetic syndrome.
Annotation: GEN or unspecified; prefer specifics; unspecified dryness of skin is indexed under SKIN DISEASES, not here
ID#: D007057

Ichthyosis Vulgaris

Definition: Most common form of ICHTHYOSIS characterized by prominent scaling especially on the exterior surfaces of the extremities. It is inherited as an autosomal dominant trait.
Annotation: do not use /congen & do not coord with INFANT, NEWBORN, DISEASES
ID#: D016112

Ichthyosis, Lamellar

Definition: A chronic, congenital ichthyosis inherited as an autosomal recessive trait. Infants are usually born encased in a collodion membrane which sheds within a few weeks. Scaling is generalized and marked with grayish-brown quadrilateral scales, adherent at their centers and free at the edges. In some cases, scales are so thick that they resemble armored plate.
Annotation: do not coord with INFANT, NEWBORN, DISEASES
ID#: D017490

Ichthyosis, X-Linked

Definition: Chronic form of ichthyosis that is inherited as a sex-linked recessive trait carried on the X-chromosome and transmitted to the male offspring. It is characterized by severe scaling, especially on the extremities, and is associated with steroid sulfatase deficiency.
Annotation: do not use /congen & do not coord with INFANT, NEWBORN, DISEASES
ID#: D016114

IgA Deficiency

Definition: A dysgammaglobulinemia characterized by a deficiency of IMMUNOGLOBULIN A.
Annotation: DF: IGA DEFIC
ID#: D017098

IgG Deficiency

Definition: A dysgammaglobulinemia characterized by a deficiency of IMMUNOGLOBULIN G.
Annotation: DF: IGG DEFIC
ID#: D017099

Ileal Diseases

Definition: Pathological development in the ILEUM including the ILEOCECAL VALVE.
Annotation: inflamm dis = ILEITIS
ID#: D007077

Ileal Neoplasms

Definition: Tumors or cancer in the ILEUM region of the small intestine (INTESTINE, SMALL).
Annotation: coord IM with histol type of neopl (IM)
ID#: D007078

Ileitis

Definition: Inflammation of any segment of the ILEUM and the ILEOCECAL VALVE.
Annotation:
ID#: D007079

Ileus

Definition: A condition caused by the lack of intestinal PERISTALSIS or INTESTINAL MOTILITY without any mechanical obstruction. This interference of the flow of INTESTINAL CONTENTS often leads to INTESTINAL OBSTRUCTION. Ileus may be classified into postoperative, inflammatory, metabolic, neurogenic, and drug-induced.
Annotation: coord IM with specific precoord intestinal dis (IM); PARALYTIC ILEUS see INTESTINAL PSEUDO-OBSTRUCTION is also available
ID#: D045823

Iliac Aneurysm

Definition: An aneurysm of the common, internal, or external iliac arteries.
Annotation: aneurysm of an iliac artery; dissecting aneurysm: coord IM with ANEURYSM, DISSECTING (IM); rupture: coord with ANEURYSM, RUPTURED (IM) or if spontaneous, with RUPTURE, SPONTANEOUS (NIM)
ID#: D017543

Illusions

Definition: The misinterpretation of a real external, sensory experience.
Annotation: do not confuse with DELUSIONS
ID#: D007088

Immersion Foot

Definition: A condition of the feet produced by prolonged exposure of the feet to water. Exposure for 48 hours or more to warm water causes tropical immersion foot or warm-water immersion foot common in Vietnam where troops were exposed to prolonged or repeated wading in paddy fields or streams. Trench foot results from prolonged exposure to cold, without actual freezing. It was common in trench warfare during World War I, when soldiers stood, sometimes for hours, in trenches with a few inches of cold water in them. (Andrews' Diseases of the Skin, 8th ed, p27)
Annotation:
ID#: D007102

Immune Complex Diseases

Definition: Group of diseases mediated by the deposition of large soluble complexes of antigen and antibody with resultant damage to tissue. Besides SERUM SICKNESS and the ARTHUS REACTION, evidence supports a pathogenic role for immune complexes in many other systemic immunologic diseases including GLOMERULONEPHRITIS, systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC) and POLYARTERITIS NODOSA.
Annotation: dis caused by deposition of antigen-antibody complexes with resultant damage to tissue; "immune complex" = IMMUNE COMPLEX see ANTIGEN-ANTIBODY COMPLEX
ID#: D007105

Immunoblastic Lymphadenopathy

Definition: A disorder characterized by proliferation of arborizing small vessels, prominent immunoblastic proliferations and amorphous acidophilic interstitial material. Clinical manifestations include fever, sweats, weight loss, generalized lymphadenopathy and frequently hepatosplenomegaly.
Annotation:
ID#: D007119

Immunologic Deficiency Syndromes

Definition: Syndromes in which there is a deficiency or defect in the mechanisms of immunity, either cellular or humoral.
Annotation: GEN or unspecified; for defic of specific immunoprotein, IMMUNOGLOBULINS or specific immunoglobulin, use specific with /defic; TN 223: definition & use; TN 225: differentiation from immunoglobulin defic; Manual 23.25.2; DF: IMMUNOL DEFIC SYNDROMES
ID#: D007153

Immunologic Diseases

Definition: Disorders caused by abnormal or absent immunologic mechanisms, whether humoral, cell-mediated or both.
Annotation: GEN: prefer specifics
ID#: D007154

Immunoproliferative Disorders

Definition: Disorders characterized by abnormal proliferation of primary cells of the immune system or by excessive production of immunoglobulins.
Annotation: GEN or unspecified: prefer specifics
ID#: D007160

Immunoproliferative Small Intestinal Disease

Definition: A condition that is caused by HYPERPLASIA of LYMPHOCYTES in the small intestine (INTESTINE, SMALL) and the mesenteric LYMPH NODES. These lymphocytes produce an anomalous heavy chain protein. Generally, these IPSID patients have either concurrent LYMPHOMA or develop lymphoma within a few years. The disease was originally described in the Mediterranean region.
Annotation:
ID#: D007161

Impetigo

Definition: A common superficial bacterial infection caused by STAPHYLOCOCCUS AUREUS or group A beta-hemolytic streptococci. Characteristics include pustular lesions that rupture and discharge a thin, amber-colored fluid that dries and forms a crust. This condition is commonly located on the face, especially about the mouth and nose.
Annotation: a staph or strep infect of the skin
ID#: D007169

Impotence

Definition: The inability to perform sexual intercourse.
Annotation:
ID#: D007172

Impotence, Vasculogenic

Definition: Impotence caused by a diminution of blood flow to the penis. Arteries involved can be the terminal aorta, hypogastric, pudendal, penile, and cavernous arteries. Ectopic drainage of the corpora cavernosa via large superficial dorsal veins or abnormally large cavernous and crural veins can cause venogenic impotence. (From Walsh, et al., Campbell's Urology, 6th ed, p720). The expression "venous leakage" is seen often in international literature. Leakage refers to the failure of the blood to reach the penile erectile tissues.
Annotation: do not coord with PENIS /blood supply + specific artery or vein unless the vasc heading is particularly discussed (probably NIM)
ID#: D018783

Impulse Control Disorders

Definition: Disorders whose essential features are the failure to resist an impulse, drive, or temptation to perform an act that is harmful to the individual or to others. Individuals experience an increased sense of tension prior to the act and pleasure, gratification or release of tension at the time of committing the act.
Annotation:
ID#: D007174

Inappropriate ADH Syndrome

Definition: Hyponatremia and renal salt loss attributed to overexpansion of body fluids resulting from sustained release of VASOPRESSINS (i.e., antiduretic hormone) despite the absence of appropriate stimuli. Associated conditions include medication effect; MENINGITIS; CRANIOCEREBRAL TRAUMA; ENCEPHALITIS; CEREBROVASCULAR DISORDERS; HYDROCEPHALUS; PNEUMONIA; ASTHMA; THYROID DISEASES; and other conditions. This condition may also be idiopathic or result from ectopic (extra-pituitary) production of ADH. (From Joynt, Clinical Neurology, 1992, Ch36, pp59-62)
Annotation:
ID#: D007177

Incontinentia Pigmenti

Definition: A genodermatosis occurring mostly in females and characterized by skin changes in three phases - vesiculobullous, verrucous papillomatous, and macular melanodermic. Hyperpigmentation is bizarre and irregular. Sixty percent of patients have abnormalities of eyes, teeth, central nervous system, and skin appendages.
Annotation: multiple skin & other abnorm; do not confuse with INCONTINENTIA PIGMENTI ACHROMIANS see PIGMENTATION DISORDERS
ID#: D007184

Inert Gas Narcosis

Definition: Progressive mental disturbances and unconsciousness due to breathing mixtures of oxygen and inert gases (argon, helium, xenon, krypton, and atmospheric nitrogen) at high pressure.
Annotation: IM; specify gas (IM)
ID#: D007222

Infant Nutrition Disorders

Definition: Disorders caused by nutritional imbalance, either overnutrition or undernutrition, occurring in infants ages 1 month to 24 months.
Annotation: GEN only; prefer specific dis with infant check tag
ID#: D007228

Infant, Newborn, Diseases

Definition: Diseases of newborn infants present at birth (congenital) or developing within the first month of birth. It does not include hereditary diseases not manifesting at birth or within the first 30 days of life nor does it include inborn errors of metabolism. Both HEREDITARY DISEASES and METABOLISM, INBORN ERRORS are available as general concepts.
Annotation: IM GEN only; for specific dis in newborn inf use specific dis (IM) + check tag INFANT, NEWBORN; do not use /compl /congen; check the tag INFANT, NEWBORN: Manual 18.5.10; relation to /congen: Manual 19.8.18, 23.21+; TN 109: relation to other Cat C16 terms
ID#: D007232

Infant, Premature, Diseases

Definition:
Annotation: IM; do not use /compl /congen & do not coord with INFANT, NEWBORN, DISEASES; check the tag INFANT, NEWBORN: Manual 23.21.4
ID#: D007235

Infarction

Definition: A pathological process consisting of a sudden insufficient blood supply to an area, which results in necrosis of that area. It is usually caused by a thrombus, an embolus, or a vascular torsion.
Annotation: GEN or unspecified; prefer specific see relateds; IM; coord with organ /blood supply (IM): Manual 23.14.2; DF: INFARCT
ID#: D007238

Infarction, Anterior Cerebral Artery

Definition: An infarction in the vascular distribution of the anterior cerebral artery which supplies the majority of the medial surface of the cerebral hemispheres, and provides branches (including Heubner's artery) to the anterior limb of the internal capsule, head of the CAUDATE NUCLEUS, and anterior GLOBUS PALLIDUS. Clinical manifestations may include contralateral lower extremity weakness and sensory loss. Bilateral anterior cerebral artery infarctions are associated with abulia, PARAPLEGIA, and URINARY INCONTINENCE. (From Adams et al., Principles of Neurology, 6th ed, pp789-93)
Annotation: DF: ACA INFARCT
ID#: D020243

Infarction, Middle Cerebral Artery

Definition: The formation of an area of coagulation necrosis in the vascular distribution of the middle cerebral artery secondary to ISCHEMIA. Clinical features include contralateral weakness and loss of sensation in the arm and face and a contralateral homonymous hemianopsia. Dominant hemisphere lesions may produce APHASIA, alexia, AGRAPHIA, acalculia, finger agnosia, and right-left confusion. Nondominant hemisphere lesions may produce unilateral neglect, dressing APRAXIA, anosognosia, and constructional apraxia. (From Adams et al., Principles of Neurology, 6th ed, p786)
Annotation:
ID#: D020244

Infarction, Posterior Cerebral Artery

Definition: Formation of an area of coagulation necrosis induced by ischemia in the vascular distribution of the posterior cerebral artery. This artery supplies portions of the MESENCEPHALON (see also BRAIN STEM INFARCTIONS) and thalamus, inferomedial TEMPORAL LOBE, and medial OCCIPITAL LOBE. Clinical manifestations vary with the size and location of infarction, but include a variety of midbrain and thalamic syndromes, HEMIANOPSIA, and behavioral syndromes related to memory and processing visual information. (From Adams et al., Principles of Neurology, 6th ed, pp793-8)
Annotation: DF: PCA INFARCT
ID#: D020762

Infection

Definition: Invasion and multiplication of microorganisms in body tissues, which may be clinically inapparent or result in local cellular injury. A local infection may persist and spread by extension to become an acute, subacute, or chronic clinical infection or disease state. It may also become systemic when the microorganisms gain access to the lymphatic or vascular system. (From Dorland, 27th ed)
Annotation: GEN only as concept of dis caused by organisms; many texts saying "infection" & many saying "sepsis" mean BACTERIAL INFECTIONS: check text but note that SEPSIS is available; "infectious disease" can be INFECTION but is more likely COMMUNICABLE DISEASES; policy: Manual 22.12-.19, 23.12+; relation to organisms: Manual 22.11-.19 & TN 209; /drug ther: consider also ANTI-INFECTIVE AGENTS & its specific groups; /prev = INFECTION CONTROL but see note there
ID#: D007239

Infectious Bovine Rhinotracheitis

Definition: A herpesvirus infection of CATTLE characterized by INFLAMATION and NECROSIS of the mucous membranes of the upper RESPIRATORY TRACT.
Annotation: check the tags ANIMALS and CATTLE; DF: INFECT BOVINE RHINOTRACHEITIS
ID#: D007241

Infectious Mononucleosis

Definition: A common, acute infection usually caused by the Epstein-Barr virus (HERPESVIRUS 4, HUMAN). There is an increase in mononuclear white blood cells and other atypical lymphocytes, generalized lymphadenopathy, splenomegaly, and occasionally hepatomegaly with hepatitis.
Annotation: if not caused by EPSTEIN-BARR VIRUS (HERPESVIRUS 4, HUMAN) coord IM with specific infection (IM)
ID#: D007244

Infertility

Definition: The diminished or absent ability to conceive or produce an offspring while sterility is the complete inability to conceive or produce an offspring.
Annotation: GEN or unspecified as male or female; prefer the specifics
ID#: D007246

Infertility, Female

Definition: Diminished or absent ability of a female to achieve conception.
Annotation: /chem ind permitted but not for testing of contraceptives
ID#: D007247

Infertility, Male

Definition: Diminished or absent ability of the male to effect conception.
Annotation: /chem ind permitted but not for testing of contraceptives
ID#: D007248

Inflammation

Definition: A pathological process characterized by injury or destruction of tissues caused by a variety of cytologic and chemical reactions. It is usually manifested by typical signs of pain, heat, redness, swelling, and loss of function.
Annotation: IM general inflammatory process; look for specific inflamm dis in MeSH as -ITIS; NIM as coord for organ /dis not in MeSH as -ITIS; /drug ther: consider also ANTI-INFLAMMATORY AGENTS & its specifics; ACUTE PHASE REACTION (an early local inflammatory reaction to inj: see MeSH definition) is available; Manual 23.13+; DF: INFLAMM
ID#: D007249

Inflammatory Bowel Diseases

Definition: Chronic, non-specific inflammation of the GASTROINTESTINAL TRACT. Etiology may be genetic or environmental. This term includes CROHN DISEASE and ULCERATIVE COLITIS.
Annotation:
ID#: D015212

Influenza

Definition: An acute viral infection involving the respiratory tract. It is marked by inflammation of the nasal mucosa, the pharynx, and conjunctiva, and by headache and severe, often generalized, myalgia.
Annotation: caused by an orthomyxovirus; coord IM with specific orthomyxovirus (IM)
ID#: D007251

Infratentorial Neoplasms

Definition: Intracranial tumors originating in the region of the brain inferior to the tentorium cerebelli, which contains the cerebellum, fourth ventricle, cerebellopontine angle, brain stem, and related structures. Primary tumors of this region are more frequent in children, and may present with ATAXIA; CRANIAL NERVE DISEASES; vomiting; HEADACHE; HYDROCEPHALUS; or other signs of neurologic dysfunction. Relatively frequent histologic subtypes include TERATOMA; MEDULLOBLASTOMA; GLIOBLASTOMA; ASTROCYTOMA; EPENDYMOMA; CRANIOPHARYNGIOMA; and choroid plexus papilloma (PAPILLOMA, CHOROID PLEXUS).
Annotation: coord IM with histol type of neopl (IM)
ID#: D015192

Insect Bites and Stings

Definition: Bites and stings inflicted by insects.
Annotation: coord IM with specific insect (IM); DF: INSECT BITES
ID#: D007299

Insomnia, Fatal Familial

Definition: An autosomal dominant disorder characterized by degeneration of the THALAMUS and progressive insomnia. It is caused by a mutation in the prion protein (PRIONS).
Annotation:
ID#: D034062

Insulin Coma

Definition: Severe HYPOGLYCEMIA induced by a large dose of exogenous INSULIN resulting in a COMA or profound state of unconsciousness from which the individual cannot be aroused.
Annotation:
ID#: D007331

Insulin Resistance

Definition: Diminished effectiveness of INSULIN in lowering blood sugar levels: Requiring the use of 200 units or more of insulin per day to prevent hyperglycemia or ketosis. It is usually due to insulin binding by antibodies (INSULIN ANTIBODIES), but abnormalities in insulin receptors (RECEPTOR, INSULIN) on cell surfaces also occur. It is associated with obesity, ketoacidosis, infection, and certain rare conditions. (from Stedman, 25th ed)
Annotation: for insulin resistance syndrome X use METABOLIC SYNDROME X
ID#: D007333

Insulinoma

Definition: A benign tumor of the PANCREATIC BETA CELLS. Insulinoma secretes excess INSULIN resulting in HYPOGLYCEMIA.
Annotation: coord IM with PANCREATIC NEOPLASMS (IM)
ID#: D007340

Intermittent Claudication

Definition: A symptom complex characterized by leg pain and weakness brought on by walking, with the disappearance of the symptoms following a brief rest.
Annotation: intermittent leg pain caused by walking
ID#: D007383

Intertrigo

Definition: A superficial dermatitis occurring on skin surfaces in contact with each other, such as the axillae, neck creases, intergluteal fold, between the toes, etc. Obesity is a predisposing factor. The condition is caused by moisture and friction and is characterized by erythema, maceration, burning, and exudation.
Annotation: a dermatitis of skin folds
ID#: D007402

Intervertebral Disk Displacement

Definition: An intervertebral disk in which the nucleus pulposus has protruded through surrounding fibrocartilage. This occurs most frequently in the lower lumbar region.
Annotation: = herniation or prolapse; coord IM with specific vertebrae (IM); ther by chemonucleolysis = INTERVERTEBRAL DISK CHEMOLYSIS: see note there
ID#: D007405

Intestinal Atresia

Definition: Congenital obliteration of the lumen of the intestine, with the ILEUM involved in 50% of the cases and the JEJUNUM and DUODENUM following in frequency. It is the most frequent cause of INTESTINAL OBSTRUCTION in NEWBORNS. (From Stedman, 25th ed)
Annotation: coord IM with specific intestine /abnorm except for duodenum: index duodenal atresia as DUODENAL OBSTRUCTION /congen (IM) + INTESTINAL ATRESIA (IM)
ID#: D007409

Intestinal Diseases

Definition: Pathological processes in any segment of the INTESTINE from DUODENUM to RECTUM.
Annotation: GEN: prefer specifics; inflamm dis = GASTROENTERITIS or specifics; consider also INFLAMMATORY BOWEL DISEASE; gas cysts = PNEUMATOSIS CYSTOIDES INTESTINALIS
ID#: D007410

Intestinal Diseases, Parasitic

Definition: Infections of the INTESTINES with PARASITES, commonly involving PROTOZOA or PARASITIC WORMS. Infections with roundworms (NEMATODE INFECTIONS) and TAPEWORMS (CESTODE INFECTIONS) are also known as HELMINTHIASIS.
Annotation: GEN; prefer specific indentations; otherwise coord IM with specific parasitic disease (IM) + specific precoord intestinal disease (IM)
ID#: D007411

Intestinal Fistula

Definition: An abnormal anatomical passage between the INTESTINE, and another segment of the intestine or other organs. External intestinal fistula is connected to the SKIN (enterocutaneous fistula). Internal intestinal fistula can be connected to a number of organs, such as STOMACH (gastrocolic fistula), the BILIARY TRACT (cholecystoduodenal fistula), or the BLADDER of the URINARY TRACT (colovesical fistula). Risk factors include inflammatory processes, cancer, radiation treatment, and surgical misadventures (MEDICAL ERRORS).
Annotation: fistula policy: Manual 23.19+; RECTAL FISTULA & RECTOVAGINAL FISTULA are also available
ID#: D007412

Intestinal Neoplasms

Definition: Tumors or cancer of the INTESTINES.
Annotation: GEN: prefer specific precoord; coord IM with histol type of neopl (IM)
ID#: D007414

Intestinal Obstruction

Definition: Any impairment, arrest, or reversal of the normal flow of INTESTINAL CONTENTS toward the ANUS.
Annotation: coord IM with specific precoord intestinal dis (IM); INTESTINAL PSEUDO-OBSTRUCTION is also available
ID#: D007415

Intestinal Perforation

Definition: Opening or penetration through the wall of the INTESTINES.
Annotation: caused by dis or inj; coord IM with specific intestine (IM) or specific precoord intestinal dis (IM); intestinal rupture does not go here: index with INTESTINES /inj or specific intestine /inj (IM) + RUPTURE (NIM) or specific intestine (IM) or specific precoord intestinal dis (IM) + RUPTURE, SPONTANEOUS (NIM)
ID#: D007416

Intestinal Polyposis

Definition: The growth of INTESTINAL POLYPS. Growth processes include neoplastic (ADENOMA and CARCINOMA) and non-neoplastic (hyperplastic, mucosal, inflammatory, and other polyps).
Annotation: INTESTINAL POLYPS is also available; familial: consider also ADENOMATOUS POLYPOSIS COLI
ID#: D044483

Intestinal Polyps

Definition: Discrete abnormal tissue masses that protrude into the lumen of the INTESTINE. A polyp is attached to the intestinal wall either by a stalk, pedunculus, or by a broad base.
Annotation: INTESTINAL POLYPOSIS is also available
ID#: D007417

Intestinal Pseudo-Obstruction

Definition: A type of ILEUS, a functional not mechanical obstruction of the INTESTINES. This syndrome is caused by a large number of disorders involving the smooth muscles (MUSCLE, SMOOTH) or the NERVOUS SYSTEM.
Annotation: coord IM with specific precoord intestinal dis (IM); INTESTINAL OBSTRUCTION and ILEUS are also available
ID#: D007418

Intestinal Volvulus

Definition: A twisting in the intestine (INTESTINES) that can cause INTESTINAL OBSTRUCTION.
Annotation:
ID#: D045822

Intracranial Aneurysm

Definition: Congenital or acquired abnormal outpouching of an intracranial blood vessel wall. Saccular (berry) aneurysms are the most common variant, and tend to form at arterial branch points near the base of the brain. Rupture results in SUBARACHNOID HEMORRHAGE or INTRACRANIAL HEMORRHAGES. Giant aneurysms (>2.5 cm in diameter) may compress adjacent structures, including the OCULOMOTOR NERVE (see also OCULOMOTOR NERVE DISEASES). (From Adams et al., Principles of Neurology, 6th ed, p841)
Annotation:
ID#: D002532

Intracranial Arterial Diseases

Definition: Conditions which affect the arteries of the brain, meninges, and intracranial portions of the cranial nerves. Relatively common disease processes in this category include: ATHEROSCLEROSIS; emboli; thrombosis (INTRACRANIAL EMBOLISM AND THROMBOSIS); VASCULITIS, CENTRAL NERVOUS SYSTEM; CEREBROVASCULAR TRAUMA; vasospasm (VASOSPASM, INTRACRANIAL); INTRACRANIAL ARTERIOVENOUS MALFORMATIONS; and infections.
Annotation:
ID#: D020765

Intracranial Arteriosclerosis

Definition: Vascular diseases characterized by thickening, hardening, and remodeling of the walls of intracranial arteries. There are three subtypes: (1) atherosclerosis, marked by fatty depositions in the innermost layer of the arterial walls, (2) Monckeberg's sclerosis, which features calcium deposition in the media and (3) arteriolosclerosis, which refers to sclerosis of small caliber arteries. Clinically, this process may be associated with ISCHEMIC ATTACK, TRANSIENT; BRAIN INFARCTION; INTRACRANIAL EMBOLISM AND THROMBOSIS; or INTRACRANIAL ANEURYSM.
Annotation:
ID#: D002537

Intracranial Arteriovenous Malformations

Definition: Congenital vascular anomalies of the brain characterized by tangles of thin walled arteries which communicate directly with veins without intervening capillaries. The malformations vary greatly in size and location, and produce symptoms through rupture (see also INTRACRANIAL HEMORRHAGES), mass effect, and vascular steal effect. Clinical presentation is often delayed until the fourth or fifth decade when affected individuals may develop headaches, seizures, and focal neurologic deficits. Large hemorrhages may result in coma or death. (From Adams et al., Principles of Neurology, 6th ed, p848)
Annotation: congen cerebral arteriovenous fistula: coord IM with ARTERIOVENOUS FISTULA/congen(IM); DF: INTRACRANIAL AVM
ID#: D002538

Intracranial Embolism

Definition: Migration of foreign material to the intracranial components of the nervous system via arterial pathways. Emboli most frequently are of cardiac origin and are associated with ARRHYTHMIA; mural thrombi; ENDOCARDITIS, SUBACUTE BACTERIAL; HEART VALVE DISEASES; and HEART SEPTAL DEFECTS. Noncardiac sources include lesions of the aorta, carotid arteries, vertebral arteries, and intracranial arteries. Emboli may be composed of thrombosed platelets, atherosclerotic debris, fat, air, tumor cells, or infectious materials, and may cause CEREBRAL INFARCTION. (From Adams et al., Principles of Neurology, 6th ed, pp824-6)
Annotation:
ID#: D020766

Intracranial Embolism and Thrombosis

Definition: Embolism or thrombosis involving blood vessels which supply intracranial structures. Emboli may originate from extracranial or intracranial sources. Thrombosis may occur in arterial or venous structures.
Annotation: Not used for indexing or cataloging.
ID#: D002542

Intracranial Hemorrhage, Hypertensive

Definition: Bleeding within the brain or adjacent structures which results from systemic HYPERTENSION, usually in association with INTRACRANIAL ARTERIOSCLEROSIS. Hypertensive hemorrhages are most frequent in the BASAL GANGLIA; CEREBELLUM; PONS; and THALAMUS; but may also involve the CEREBRAL CORTEX, subcortical white matter, and other brain structures.
Annotation:
ID#: D020299

Intracranial Hemorrhage, Traumatic

Definition: Bleeding within the cranial vault induced by penetrating and nonpenetrating traumatic injuries, including hemorrhages into the epidural, subdural and subarachnoid spaces, cerebral hemispheres, DIENCEPHALON; BRAIN STEM; and CEREBELLUM.
Annotation: BRAIN HEMORRHAGE, TRAUMATIC and specifics are available
ID#: D020198

Intracranial Hemorrhages

Definition: Bleeding within the intracranial cavity, including hemorrhages in the brain and within the cranial epidural, subdural, and subarachnoid spaces.
Annotation:
ID#: D020300

Intracranial Hypertension

Definition: Increased pressure within the cranial vault. This may result from several conditions, including HYDROCEPHALUS; BRAIN EDEMA; intracranial masses; severe systemic HYPERTENSION; PSEUDOTUMOR CEREBRI; and other disorders.
Annotation: do not confuse with INTRACRANIAL HYPOTENSION; coord IM with disease /physiopathol (IM) causing or caused by intracranial hypertension
ID#: D019586

Intracranial Hypotension

Definition: Reduction of CEREBROSPINAL FLUID pressure characterized clinically by HEADACHE which is maximal in an upright posture and occasionally by an abducens nerve palsy (see ABDUCENS NERVE DISEASES), neck stiffness, hearing loss (see DEAFNESS), NAUSEA, and other symptoms. This condition may be spontaneous or secondary to SPINAL PUNCTURE; NEUROSURGICAL PROCEDURES; DEHYDRATION; UREMIA; trauma (see also CRANIOCEREBRAL TRAUMA); and other processes. Chronic hypotension may be associated with subdural hematomas (see HEMATOMA, SUBDURAL) or hygromas. (From Semin Neurol 1996 Mar;16(1):5-10; Adams et al., Principles of Neurology, 6th ed, pp637-8)
Annotation: do not confuse with INTRACRANIAL HYPERTENSION; coord IM with disease /physiopathol (IM) causing or caused by intracranial hypotension
ID#: D019585

Intracranial Thrombosis

Definition: Formation of a clot composed of platelets and fibrin within the lumen of an intracranial artery or vein, which may result in CEREBRAL INFARCTION. Arterial thrombosis is associated with INTRACRANIAL ARTERIOSCLEROSIS, but may also result from hypercoagulability states (see THROMBOPHILIA). Cerebral vein thrombosis is frequently complicated by INTRACRANIAL HEMORRHAGES.
Annotation:
ID#: D020767

Intraoperative Complications

Definition: Complications that affect patients during surgery. They may or may not be associated with the disease for which the surgery is done, or within the same surgical procedure.
Annotation: few qualif apply; IM; coord with Cat E4 term (IM) if pertinent with or without /adv eff depending on its relation to the intraop compl: for policy apply principles of POSTOPERATIVE COMPLICATIONS, Manual 23.18+; for iatrogenic compl (as X ref SURGICAL INJURIES) or other: TN 179; DF: INTRAOP COMPL
ID#: D007431

Intussusception

Definition: A form of intestinal obstruction caused by the PROLAPSE of a part of the intestine into the adjoining intestinal lumen. There are four types: colic, involving segments of the LARGE INTESTINE; enteric, involving only the SMALL INTESTINE; ileocecal, in which the ILEOCECAL VALVE prolapses into the CECUM, drawing the ILEUM along with it; and ileocolic, in which the ileum prolapses through the ileocecal valve into the COLON.
Annotation: coord IM with specific precoord intestinal dis term; ileocolic intussusception = ILEAL DISEASES (IM) + INTUSSUSCEPTION (IM) but not also COLONIC DISEASES; ileocecal intussusception = ILEOCECAL VALVE (IM) + INTUSSUSCEPTION (IM) + ILEAL DISEASES (NIM) but not also CECAL DISEASES; cecocolic intussusception = CECAL DISEASES (IM) + INTUSSUSCEPTION (IM) but not also COLONIC DISEASES
ID#: D007443

Inversion (Genetics)

Definition: An aberration in which a chromosomal segment is deleted and reinserted in the same place but turned 180 degrees from its original orientation, so that the gene sequence for the segment is reversed with respect to that of the rest of the chromosome.
Annotation: DF: INVERSION
ID#: D007446

Iridocyclitis

Definition: Acute or chronic inflammation of the iris and ciliary body characterized by exudates into the anterior chamber, discoloration of the iris, and constricted, sluggish pupil. Symptoms include radiating pain, photophobia, lacrimation, and interference with vision.
Annotation: a type of anterior uveitis
ID#: D015863

Iris Diseases

Definition: Diseases, dysfunctions, or disorders of or located in the iris.
Annotation:
ID#: D007499

Iris Neoplasms

Definition: Tumors of the iris characterized by increased pigmentation of melanocytes. Iris nevi are composed of proliferated melanocytes and are associated with neurofibromatosis and malignant melanoma of the choroid and ciliary body. Malignant melanoma of the iris often originates from preexisting nevi.
Annotation: /blood supply /chem /second /secret /ultrastruct permitted; coord IM with histol type of neopl (IM)
ID#: D015811

Iritis

Definition: Inflammation of the iris characterized by circumcorneal injection, aqueous flare, keratotic precipitates, and constricted and sluggish pupil along with discoloration of the iris.
Annotation: a type of anterior uveitis
ID#: D007500

Iron Metabolism Disorders

Definition: Disorders in the processing of iron in the body: its absorption, transport, storage, and utilization. (From Mosby's Medical, Nursing, & Allied Health Dictionary, 4th ed)
Annotation: GEN or unspecified; prefer specifics; DF: IRON METAB DIS
ID#: D019189

Iron Overload

Definition: An excessive accumulation of iron in the body due to a greater than normal absorption of iron from the gastrointestinal tract or from parenteral injection. This may arise from idiopathic hemochromatosis, excessive iron intake, chronic alcoholism, certain types of refractory anemia, or transfusional hemosiderosis. (From Churchill's Illustrated Medical Dictionary, 1989)
Annotation: disord of iron metab
ID#: D019190

Irritable Bowel Syndrome

Definition: A disorder with chronic or recurrent colonic symptoms without a clearcut etiology. This condition is characterized by chronic or recurrent ABDOMINAL PAIN, bloating, MUCUS in FECES, and an erratic disturbance of DEFECATION.
Annotation:
ID#: D043183

Isaacs Syndrome

Definition: A rare neuromuscular disorder with onset usually in late childhood or early adulthood, characterized by intermittent or continuous widespread involuntary muscle contractions; FASCICULATION; hyporeflexia; MUSCLE CRAMP; MUSCLE WEAKNESS; HYPERHIDROSIS; TACHYCARDIA; and MYOKYMIA. Involvement of pharyngeal or laryngeal muscles may interfere with speech and breathing. The continuous motor activity persists during sleep and general anesthesia (distinguishing this condition from STIFF-PERSON SYNDROME). Familial and acquired (primarily autoimmune) forms have been reported. (From Ann NY Acad Sci 1998 May 13;841:482-496; Adams et al., Principles of Neurology, 6th ed, p1491)
Annotation:
ID#: D020386

Ischemia

Definition: Blood deficiency in an organ or tissue caused by a constriction or obstruction of its blood vessels.
Annotation: GEN or unspecified; prefer specifics of which MYOCARDIAL ISCHEMIA & BRAIN ISCHEMIA & their specifics are most common; IM; coord with specific organ /blood supply (IM)
ID#: D007511

Ischemic Attack, Transient

Definition: Brief reversible episodes of focal, nonconvulsive ischemic dysfunction of the brain having a duration of less than 24 hours, and usually less than one hour, caused by transient thrombotic or embolic blood vessel occlusion or stenosis. Events may be classified by arterial distribution, temporal pattern, or etiology (e.g., embolic vs. thrombotic). (From Adams et al., Principles of Neurology, 6th ed, pp814-6)
Annotation: DF: BRAIN TIA
ID#: D002546

Isochromosomes

Definition: Metacentric chromosomes produced during MEIOSIS or MITOSIS when the CENTROMERE splits transversely instead of longitudinally. The chromosomes produced by this abnormal division are one chromosome having the two long arms of the original chromosome, but no short arms, and the other chromosome consisting of the two short arms and no long arms. Each of these isochromosomes constitutes a simultaneous duplication and deletion.
Annotation: note category
ID#: D018404

Isosporiasis

Definition: Infection with parasitic protozoa of the genus ISOSPORA, producing intestinal disease. It is caused by ingestion of oocysts and can produce tissue cysts.
Annotation: /drug ther: consider also COCCIDIOSTATS
ID#: D021865