Bma Illustrated Medical Dictionary

5 days. Transplanted hairs fall out shortly

afterwards, but new hairs grow from the

follicles 3 weeks to 3 months later.

Other transplant techniques include

punch grafting, in which a punch is used

to remove small areas of bald scalp,

which are replaced with areas of hairy

scalp; flap grafting, in which flaps of

hairy skin are lifted, rotated, and

stitched to replace bald areas; and male

pattern baldness reduction, which

involves cutting out areas of bald skin

and stretching surrounding areas of

hair-bearing scalp to replace them.

half-lifeThe time taken for the activity

of a substance to reduce to half its

original level. The term is usually used

to refer to the time taken for the level

of radiationemitted by a radioactive

substance to decay to half its original

level. The concept is useful in radiother-

apyfor assessing how long material will

stay radioactive in the body. Half-life is

also used to refer to the length of time

taken by the body to eliminate half the

quantity of a drug.

halitosisThe medical term for bad

breath. Halitosis is usually a result of

smoking, drinking alcohol, eating garlic

or onions, or poor oral hygiene. Persis-

tent bad breath not caused by any of

these may be a symptom of mouth

infection, sinusitis, or certain lung disor-

ders, such as bronchiectasis.

hallucinationA perception that occurs

when there is no external stimulus.

Auditory hallucinations (the hearing of

voices) are a major symptom of schizo-

phreniabut may also be caused by

manic–depressive illness and certain

brain disorders. Visual hallucinations are

most often found in states of delirium

brought on by a physical illness (such

as pneumonia) or alcohol withdrawal

(delirium tremens). Hallucinogenic drugs

are another common cause of visual

hallucinations. Hallucinations of smell

are associated with temporal lobe epi-

lepsy. Those of touch and taste are rare,

however, and occur mainly in people

with schizophrenia. People subjected

to sensory deprivationor overwhelming

physical stress sometimes suffer from

temporary hallucinations.

hallucinogenic drugA drug that caus-

es hallucination. Hallucinogens include

certain drugs of abuse, such as LSD,

marijuana, mescaline, and psilocybin.

Some prescription drugs, including

anticholinergic drugs and levodopa,

occasionally cause hallucinations.

halluxThe medical name for the big toe.

hallux rigidusLoss of movement in

the large joint at the base of the big toe

HAIR TRANSPLANT

HALF-LIFE HALLUX RIGIDUS

H

Area of hair removal

Recipient

site

Hair

follicle

TRANSPLANTED

HAIRS

STRIP GRAFTING TECHNIQUE

Scalpel

Incision

DONOR SITE

Magnifying

glasses

Transplanted hair