Excimer laser
Excimer laser: A laser that emits very concentrated light in the ultraviolet (UV) region of the spectrum.
Excimer lasers are used, for example, in:
Ophthalmology — to vaporize part of the surface layer of the cornea and thus reshape the cornea to correct refractive errors from myopia (nearsightedness), hyperopia (farsightedness), and astigmatism.
Dermatology — to treat psoriasis and vitiligo.
An excimer laser uses a noble-gas halide. Excimer is a chemical term that refers to a substance formed by the joining of two atoms or two molecules of the same chemical composition in an excited state; it is an excited dimer.
Read Also:
- Excise
Excise: To cut out entirely. For example, a scalpel or laser beam may be used to excise a tumor. The terms excise and resect are not synonymous. Excise implies total removal, whereas resect does not.
- Excision
Excision: 1. Surgical removal, as in the excision of a tumor. 2. The removal as if by surgery, as in excision of a tumor; implying at least partial, if not complete, removal.
- Excisional
Excisional: Pertaining to the act of excision, of removal by surgery. An excisional biopsy is one in which the lesion is removed by the biopsy. From the Greek ektome meaning excision.
- Excisional biopsy
Excisional biopsy: A biopsy in which an entire lesion is removed. A excisional biopsy is in contrast to an incisional biopsy in which only a sample of tissue is cut from a mass (incised) and removed.
- Exclamation point hair
Exclamation point hair: Exclamation point hair is a key diagnostic finding in a disorder called alopecia areata. Alopecia areata is patchy baldness (alopecia means baldness and areata means occurring in patches), which typically begins with patchy hair loss on the scalp and sometimes progresses to complete baldness and even loss of body hair. The hair […]