Laser-assisted uvulopalatoplasty Health Dictionary

Laser-assisted Uvulopalatoplasty: From 1 Different Sources


Excimer Laser

A type of laser that is used to remove thin sheets of tissue from the surface of the cornea (see EYE), thus changing the curvature of the eye’s corneal surface. The procedure is used to excise diseased tissue or to correct myopia (see REFRACTION), when it is known as photorefractive keratectomy or lasik.... excimer laser

Laser

Laser stands for Light Ampli?cation by Stimulated Emission of Radiation. The light produced by a laser is of a single wavelength and all the waves are in phase with each other, allowing a very high level of energy to be projected as a parallel beam or focused on to a small spot.

Various gases, liquids and solids will emit light when they are suitably stimulated. A gassed laser is pumped by the ionising e?ect of a high-voltage current. This is the same process as that used in a ?uorescent tube. Each type of laser has a di?erent e?ect on biological tissues and this is related to the wavelength of the light produced. The wavelength determines the degree of energy absorption by di?erent tissues, and because of this, di?erent lasers are needed for di?erent tasks. The argon laser produces light in the visible green wavelength which is selectively absorbed by HAEMOGLOBIN. It heats and coagulates (see COAGULATION) tissues so can be used to seal bleeding blood vessels and to selectively destroy pigmented lesions. The carbon-dioxide laser is the standard laser for cutting tissue: the infra-red beam it produces is strongly absorbed by water and so vaporises cells. Thus, by moving a ?nely focused beam across the tissue, it is possible to make an incision.

The two main uses of laser in surgery are the endoscopic (see ENDOSCOPE) photocoagulation of bleeding vessels, and the incision of tissue. Lasers have important applications in OPHTHALMOLOGY in the treatment of such disorders as detachment of the retina and the diabetic complications of proliferative retinopathy and of the cornea (see EYE, DISORDERS OF). The destruction of abnormal cells – a sign of pre-malignancy – in the CERVIX UTERI is done using lasers. The beams may also be used to remove scar tissue from the FALLOPIAN TUBES resulting from infection, thus unblocking the tubes and improving the chances of CONCEPTION. Lasers also have several important applications in DERMATOLOGY. They are used in the treatment of pigmented lesions such as LENTIGO, in the obliteration of port-wine stains, in the removal of small, benign tumours such as verrucas, and ?nally in the removal of tattoos.

Low-intensity laser beams promote tissue healing and reduce in?ammation, pain and swelling. Their e?ect is achieved by stimulating blood and lymph ?ow and by cutting the production of PROSTAGLANDINS, which provoke in?ammation and pain. The beams are used to treat ligament sprains, muscle tears and in?amed joints and tendons.

The three great advantages of lasers are their potency, their speed of action, and the ability to focus on an extremely small area. For these reasons they are widely used, and have allowed great advances to be made in microsurgery, and particularly in FIBREOPTIC ENDOSCOPY.... laser

Assisted Conception

(Further information about the subject and the terms used can be found at http:// www.hfea.gov.uk/glossary)

This technique is used when normal methods of attempted CONCEPTION or ARTIFICIAL INSEMINATION with healthy SEMEN have failed. In the UK, assisted-conception procedures are governed by the Human Fertilisation & Embryology Act 1990, which set up the Human Fertilisation & Embryology Authority (HFEA).

Human Fertilisation & Embryology Act 1990 UK legislation was prompted by the report on in vitro fertilisation produced by a government-appointed committee chaired by Baroness Warnock. This followed the birth, in 1978, of the ?rst ‘test-tube’ baby.

This Act allows regulation monitoring of all treatment centres to ensure that they carry out treatment and research responsibly. It covers any fertilisation that uses donated eggs or sperm (called gametes) – for example, donor insemination or embryos (see EMBRYO) grown outside the human body (known as licensed treatment). The Act also covers research on human embryos with especial emphasis on foolproof labelling and immaculate data collection.

Human Fertilisation & EmbryologyAuthority (HFEA) Set up by the UK government following the Warnock report, the Authority’s 221 members inspect and license centres carrying out fertilisation treatments using donated eggs and sperm. It publishes a code of practice advising centres on how to conduct their activities and maintains a register of information on donors, patients and all treatments. It also reviews routinely progress and research in fertility treatment and the attempted development of human CLONING. Cloning to produce viable embryos (reproductive cloning) is forbidden, but limited licensing of the technique is allowed in specialist centres to enable them to produce cells for medical treatment (therapeutic cloning).

In vitro fertilisation (IVF) In this technique, the female partner receives drugs to enhance OVULATION. Just before the eggs are released from the ovary (see OVARIES), several ripe eggs are collected under ULTRASOUND guidance or through a LAPAROSCOPE. The eggs are incubated with the prepared sperm. About 40 hours later, once the eggs are fertilised, two eggs (three in special circumstances) are transferred into the mother’s UTERUS via the cervix (neck of the womb). Pregnancy should then proceed normally. About one in ?ve IVF pregnancies results in the birth of a child. The success rate is lower in women over 40.

Indications In women with severely damaged FALLOPIAN TUBES, IVF o?ers the only chance of pregnancy. The method is also used in couples with unexplained infertility or with male-factor infertility (where sperms are abnormal or their count low). Women who have had an early or surgically induced MENOPAUSE can become pregnant using donor eggs. A quarter of these pregnancies are multiple – that is, produce twins or more. Twins and triplets are more likely to be premature. The main danger of ovarian stimulation for IVF is hyperstimulation which can cause ovarian cysts. (See OVARIES, DISEASES OF.)... assisted conception

Assisted Living

See “residential care services”; “assisted living facility”.... assisted living

Assisted Suicide

The act of intentionally killing oneself with the assistance of another who provides the knowledge, means or both.... assisted suicide

Assisted Living Facility / Assisted Care Living Facility

Establishment which provides accommodation and care for older or disabled persons who cannot live independently but do not need nursing care. Residents are also provided with domestic assistance (meals, laundry, personal care).... assisted living facility / assisted care living facility

Computer-assisted Diagnosis

The use of information technology to assist health care professionals in diagnosis. This usually involves a dialogue between a computer system and a clinician. The systems are generally regarded as support systems for clinicians; the final responsibility for decision-making resides with the clinician.... computer-assisted diagnosis

Computer-assisted Therapy

The application of computer technology to therapy.... computer-assisted therapy

Drug Assisted Rape

Also known as ‘date rape’, this is an unwelcome phenomenon in which an intending rapist undermines a potential victim’s resistance by giving her a hypnotic drug such as benzodiazepine. The British National Formulary warns that ?unitrazepam (Rohypnol®) tablets may be particularly subject to abuse – perhaps given to the unsuspecting victim in an alcoholic drink so the sedative e?ect is greatly enhanced.... drug assisted rape

Group Senior Assisted Housing

See “assisted living facility”.... group senior assisted housing

Physician-assisted Suicide

See SUICIDE.... physician-assisted suicide

Laser Treatment

Use of a laser beam in a variety of medical procedures. Highintensity laser beams cut through tissue and cause blood clotting. They can be used in surgery and to destroy abnormal blood vessels. Lasers are frequently used in ophthalmology to treat eye disorders, in gynaecology (for example, to unblock fallopian tubes), and to remove birthmarks and tattoos.... laser treatment

Argon Laser

a type of *laser that utilizes argon gas to produce a beam of intense light, used especially in eye surgery to treat disease of the retina (e.g. diabetic retinopathy) or glaucoma (as in argon laser *trabeculoplasty). See also photocoagulation.... argon laser

Computer-assisted Surgery

(image-guided surgery, surgical navigation) a technique by which a virtual image or map of the patient is created from CT scans, MRI scans, X-rays, or ultrasound scans and loaded into a computer. Special instruments connected to the computer are then applied to certain reference points on the patient. The computer can then produce a picture of the location of the instrument within the patient.... computer-assisted surgery

Diode Laser

a type of laser whose medical uses include treating diseases of the retina, by producing small burns in the retina (see photocoagulation), and selected cases of glaucoma (cyclophotocoagulation). It is also used for treating varicose veins (see endovenous laser treatment).... diode laser

Endovenous Laser Treatment

(EVLT) a minimally invasive procedure to treat *varicose veins. A laser fibre (usually an 810-nm *diode laser) contained within a sheath is fed into the vein by ultrasound guidance and slowly withdrawn as it is fired, thereby delivering laser energy that causes irreversible destruction and eventual ablation of the vein.... endovenous laser treatment

Femtosecond Laser

a laser that emits optical pulses with a duration of femtoseconds (fs; 1 fs = 10?15 s), allowing micrometer-level accuracy and needle– or blade-free surgery. It has the potential to carry out lens extraction or cataract surgery through a pin-prick incision.... femtosecond laser

Holmium:yag Laser

a type of *YAG laser that uses a short-pulsed high-energy beam with a wavelength of 2100 nm to cut, perforate, and fragment tissue. It has a penetration of 0.4 mm. This laser is used in the fragmentation of urinary tract calculi (stones) and in *enucleation of the prostate gland.... holmium:yag laser

Laser Doppler Flowmeter

a non-invasive instrument for measuring blood flow through tissue (e.g. skin) utilizing a laser beam.... laser doppler flowmeter

Scanning Laser Ophthalmoscope

see ophthalmoscope.... scanning laser ophthalmoscope

Selective Laser Trabeculoplasty

(SLT) see trabeculoplasty.... selective laser trabeculoplasty

 yag Laser

a type of *laser whose active medium is a crystal of yttrium, aluminium, and garnet. It is used for cutting tissue, for example in lens *capsulotomy or *iridotomy. Specialized types (e.g. the *holmium:YAG laser) are used for various specific purposes....  yag laser



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