All articles starting with H

Hemicorporectomy

Hemicorporectomy, or translumbar amputation, is an ultra-radical surgery removing the lower half of the body at the lumbar spine, with aorta, vena cava, and spinal cord transection. About 79 cases reported; used for pelvic malignancy, osteomyelitis, and trauma.

Hemicrania continua

Hemicrania continua, a rare indomethacin-responsive trigeminal autonomic cephalalgia, causes continuous strictly unilateral headache with ipsilateral tearing, conjunctival injection, or agitation, diagnosed by ICHD-3 criteria and treated with indomethacin.

Hemidactylus

Hemidactylus (Oken, 1817) is a genus of over 165 gekkonid gecko species, the house geckos; includes commensal invaders H. frenatus, H. mabouia, H. turcicus, and island radiations on Socotra and Cape Verde.

Hemidystonia-hemiatrophy syndrome

Hemidystonia-hemiatrophy (HD-HA) syndrome, ORPHA:306741, ICD-10 G24.8: a rare dystonia with hemidystonia and ipsilateral hemiatrophy, usually after perinatal or infantile cerebral injury, stroke, or trauma; fewer than 1 per million.

Hemiepiphysiodesis

Hemiepiphysiodesis is a pediatric orthopedic technique that arrests growth on one side of a growth plate, letting the other side grow to straighten angular limb deformities in children.

Oct 20, 2026

Hemifacial hyperplasia

Hemifacial hyperplasia (hemifacial hypertrophy, facial hemihypertrophy, ORPHA:141145, OMIM 133900) is a rare congenital unilateral overgrowth of facial bone, soft tissue, and teeth, true or partial, isolated or syndromic, treated after growth ceases.

Hemifacial myohyperplasia

Hemifacial myohyperplasia (HFMH) is a rare congenital disorder of unilateral overgrowth of the facial muscles only, without bone or other organ involvement; neonatal onset, prevalence under 1 in 1,000,000, described as a syndrome by Lee et al. in 2001.

Hemifacial spasm

Hemifacial spasm (HFS), also called hemispasme facial, is a movement disorder of unilateral involuntary facial muscle contractions, usually from vascular compression of the facial nerve root exit zone; treated with botulinum toxin and curative microvascular decompression (~90% spasm freedom).

Hemihepatectomy

Hemihepatectomy, including right hemihepatectomy, is a major hepatobiliary operation that removes one half of the liver, right or left, along the Cantlie line, reserved mainly for malignant tumors.

Oct 20, 2026

Hemihyperplasia-multiple lipomatosis syndrome

Hemihyperplasia-multiple lipomatosis syndrome (HHML) is a rare PIK3CA-related overgrowth disorder with asymmetric nonprogressive hemihyperplasia, multiple recurrent lipomas, vascular malformations, and possible embryonal malignancy risk.

Hemilaminectomy

A hemilaminectomy is a spinal decompression procedure that removes bone on one side of a vertebral arch, used in dogs for disc extrusion and in humans for lumbar stenosis.

Hemileia vastatrix

Hemileia vastatrix, coffee leaf rust, is a basidiomycete rust fungus described by Berkeley and Broome in 1869 in Ceylon; it destroyed Ceylon's coffee industry, spread worldwide by 1985, and causes USD 1–2 billion annual losses.

Hemimandibulectomy

Hemimandibulectomy is the surgical removal of one half of the mandible, performed mainly for oral cancers that invade the jawbone, and usually requiring reconstruction, often with a free fibula flap.

Hemimegalencephaly

Hemimegalencephaly (unilateral megalencephaly) is a rare congenital brain malformation with overgrowth of one cerebral hemisphere, causing infantile drug-resistant epilepsy, hemiparesis, and developmental delay; caused by somatic PI3K-AKT-mTOR mutations and treated with hemispherectomy.

Hemimetabolism

Hemimetabolism, or incomplete metamorphosis, is insect development in which nymphs resemble adults and wings grow externally through molts, with no pupa; seen in grasshoppers, cockroaches, and true bugs, and ancestral to holometaboly.

Oct 15, 2026

Hemin

Hemin is ferric protoporphyrin IX chloride, the Fe(III) form of heme; synthesized by Hans Fischer in 1929, it treats acute hepatic porphyria and mimics peroxidase in biosensors.

Hemingway (Mercurian crater)

Hemingway is a 130-km-wide impact crater on Mercury at 17.5°N, 2.9°W, imaged by MESSENGER; its floor has possible volcanic depressions and a dark blue low-reflectance patch, named per IAU artist-naming rules.

Hemingway & Gellhorn

Hemingway & Gellhorn is a 2012 HBO biographical drama directed by Philip Kaufman, starring Clive Owen as Ernest Hemingway and Nicole Kidman as Martha Gellhorn, covering their 1936 meeting through their 1945 divorce; shot entirely in San Francisco.

Hemiparesis

Hemiparesis is one-sided body weakness, usually from stroke or other brain, spinal cord, or nerve lesions; milder than hemiplegia, contralateral to brain lesions, treated with rehabilitation.

Hemiparkinsonism-hemiatrophy syndrome

Hemiparkinsonism-hemiatrophy syndrome (HPHA, HP-HA syndrome) is a rare parkinsonian disorder with unilateral body atrophy and ipsilateral bradykinesia, rigidity, and tremor, onset in adolescence or adulthood, prevalence under 1 per million, and variable levodopa response.