vitreo-, vitre-, vitr- +
(Latin: glass; glassy; like glass)
2. The process whereby glass becomes partly crystallized as it cools (usually too slowly) from the molten state.
3. The crystals formed by this process.
Devitrification may also occur on the surface as a result of unsuccessful annealing* or accidental heating to a high temperature. It is not caused by chemical reaction between glass and its environment, which is known as weathering.
*Annealing refers to the process of slowly cooling a completed object in an auxiliary part of a glass furnace, or in a separate furnace.
This is an integral part of glassmaking because if a hot glass object is allowed to cool too quickly, it will be highly strained by the time it reaches room temperature; indeed, it may break as it cools. Highly strained glasses break easily if subjected to mechanical or thermal shock.
2. To cause (a glassy material) to become crystalline and brittle.
3. With reference to a volcanic rock or to a particle; to undergo a change in texture from glassy to crystalline.
2. Literally, "in glass", as in a test tube.
A test that is performed in vitro is one that is done in glass or plastic vessels in a laboratory.
In vitro is the opposite of in vivo (in a living organism).
The process of in vitro fertilization involves hormonally controlling the ovulatory process, removing ova (eggs) from the woman's ovaries, like in Jennifer's case, and letting sperm fertilize them in a fluid medium. The fertilized egg (zygote) is then transferred to Jennifer's uterus with the purpose of having a successful pregnancy.2. Etymology: In vitro is Latin for "in glass", referring to the test tubes; however, neither glass nor test tubes are used, and the term refers generically to laboratory procedures. Babies that are born as a result of in vitro fertilization are sometimes called "test tube babies".
2. A substance imperfectly vitrified.
2. A curtain of light and translucent material intended to be secured directly to the woodwork of a French casement window or a glazed door.
2. A coal lithotype characterized by a brilliant, glassy appearance, jet-black color, cubic cleavage, and conchoidal fracture; a component of bonded coal; pure coal.
This may be done because it has blood and scar tissue in it that blocks sight. An eye surgeon then replaces the clouded gel with a clear fluid.
3. Removal of the whole or part of the vitreous body in treating endophthalmitis, diabetic retinopathy, retinal detachment, intraocular foreign bodies, and some types of glaucoma.
Surgical procedures which may be used as part of modern vitrectomy surgeries
- Membranectomy: the removal of layers of unhealthy tissue from the retina with minute instruments; such as, forceps (tiny grasping tools), picks (miniature hooks), and visco-dissection (separating layers or tissue with jets of fluid).
- Fluid-gas exchange: the injection of gas into the eye; such as, sulphur hexaflouride or perflouropropane to hold the retina in place or to temporarily seal off holes in the retina. These gases disappear spontaneously once they have accomplished their purpose.
- Silicon oil injection: filling the eye with liquid silicon to hold the retina in place.
- Photocoagulation: a laser treatment to seal off holes in the retina or to shrink unhealthy, harmful blood vessels which grow in some diseases; such as, diabetes.
- Scleral buckling: the placement of a support positioned similar to a belt around the walls of the eyeball to hold the retina in a proper, attached position.
- Lensectomy: removal of the lens in the eye when it is cloudy (cataract) or if it is attached to scar tissue.