Spectral domain optical coherence tomography Health Dictionary

  1. Health Encyclopedia
  2. Spectral Domain Optical Coherence Tomography

Spectral Domain Optical Coherence Tomography: From 1 Different Sources

(Fourier domain OCT) a noncontact noninvasive imaging technique that can reveal layers of the retina by looking at the interference patterns of reflected laser light. Automated software is able to outline the retinal nerve-fibre layer with great precision, which is relevant in glaucoma.
Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Tomography

A technique using X-RAYS or ULTRASOUND to build up a focused image of a ‘slice’ through the body at a given level. By producing a series of such slices at di?erent depths, a three-dimensional image of the body structures can be built up.... tomography

Computed Tomography

Tomography is an X-ray examination technique in which only structures in a particular plane produce clearly focused images. Whole-body computed tomography was introduced in 1977 and has already made a major impact in the investigation and management of medical and surgical disease. The technique is particularly valuable where a mass distorts the contour of an organ (e.g. a pancreatic tumour – see PANCREAS, DISORDERS OF) or where a lesion has a density di?erent from that of surrounding tissue (e.g. a metastasis in the LIVER).

Computed tomography can distinguish soft tissues from cysts or fat, but in general soft-tissue masses have similar appearances, so that distinguishing an in?ammatory mass from a malignant process may be impossible. The technique is particularly useful in patients with suspected malignancy; it can also de?ne the extent of the cancer by detecting enlarged lymph nodes, indicating lymphatic spread. The main indications for computed tomography of the body are: mediastinal masses, suspected pulmonary metastases, adrenal disease, pancreatic masses, retroperitoneal lymph nodes, intra-abdominal abscesses, orbital tumours and the staging of cancer as a guide to e?ective treatment.... computed tomography

Positron Emission Tomography

See

PET scanning.... positron emission tomography

Computerised Tomography

See COMPUTED TOMOGRAPHY.... computerised tomography

General Optical Council

The statutory body that regulates the professions of ophthalmic OPTICIAN (optometrist) and dispensing optician. It promotes high standards of education and professional conduct and was set up by the Opticians Act 1958.... general optical council

Positron-emission Tomography (pet)

See PET SCANNING.... positron-emission tomography (pet)

Computerized Tomography

(CT) a form of X-ray examination in which the X-ray source and detector (CT scanner) rotate around the object to be scanned and the information obtained can be used to produce cross-sectional images (see cross-sectional imaging) by computer (a CT scan). A higher radiation dose is received by the patient than with some conventional X-ray techniques, but the diagnostic information obtained is far greater and should outweigh the increased risk. CT scanning can be used for all parts of the body. The data obtained can be used to construct three-dimensional images of structures of interest. See also multidetector computerized tomography; spiral CT scanning.... computerized tomography

Fourier Domain Oct

see spectral domain optical coherence tomography.... fourier domain oct

Multidetector Computerized Tomography

(MDCT) a development of *spiral CT scanning that uses more than one array of detectors opposite the X-ray tube, so that more tissue can be included, with thinner cuts, in a single rotation of the machine. This is particularly important for three-dimensional reconstruction of tissues. It also allows volumetric scanning or *isotropic imaging, which are best achieved when the thickness of the slice is similar to the size resolution of the detectors in the other two planes. Modern CT scanners are now usually equipped with between 16 and 640 detector arrays. The technique is particularly valuable for imaging fast-moving structures, such as the heart.... multidetector computerized tomography

Optical Activity

the property possessed by some substances of rotating the plane of polarization of polarized light. A compound that rotates the plane to the left is described as laevorotatory (or l-); one that rotates the plane to the right is described as dextrorotatory (or d-).... optical activity

Optical Coherence Tomography

(OCT) a class of optical tomographic techniques that allows extremely high-quality micrometre-resolution three-dimensional images to be obtained from within optical scattering media (e.g. biological tissue). OCT is proving valuable in ophthalmology, for noninvasive imaging of the ocular structures, and in cardiology for visualizing the interior of coronary arteries using a specialized *catheter. See also spectral domain optical coherence tomography.... optical coherence tomography

Single Photon Emission Computed Tomography

see SPECT scanning.... single photon emission computed tomography

Health encyclopedia icon Health Encyclopedia

Recent Searches