nuclear magnetic resonance

resonance /res·o·nance/ (rez´o-nins)

1. the prolongation and intensification of sound produced by transmission of its vibrations to a cavity, especially such a sound elicited by percussion.

2. a vocal sound heard on auscultation.

3. the existence of organic chemical structures that can not be accurately represented by a single structural formula, the actual formula lying intermediate between several possible representations differing only in electron position.

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amphoric resonance  an auscultatory sound like that produced by blowing over the mouth of an empty bottle.

nuclear magnetic resonance  a measure, by means of applying an external magnetic field to a solution in a constant radiofrequency field, of the magnetic moment of atomic nuclei to determine the structure of organic compounds; the technique is used in magnetic resonance imaging.

skodaic resonance  increased percussion resonance at the upper part of the chest, with flatness below it.

tympanitic resonance 

1. the percussion sound heard on an abdomen with tympanites.

2. the drumlike reverberation of a cavity full of air.

vocal resonance  (VR) the sound of ordinary speech as heard through the chest wall.

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nuclear magnetic resonance

n.

Abbr. NMR The absorption of electromagnetic radiation of a specific frequency by an atomic nucleus that is placed in a strong magnetic field, used especially in spectroscopic studies of molecular structure and in medicine to measure rates of metabolism.

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nuclear magnetic resonance.

See magnetic resonance.

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nuclear [noo´kle-ar]

pertaining to a nucleus.

nuclear magnetic resonance a phenomenon exhibited by many atomic nuclei: when placed in a constant magnetic field, the nuclei absorb electromagnetic radiation at a few characteristic frequencies. By applying an external magnetic field to a solution in a constant radio frequency field, it is possible to determine the structure of an unknown compound. An application of this technique, called magnetic resonance imaging, permits imaging of soft tissues of the body by distinguishing between hydrogen atoms in different environments.

nuclear medicine technologist a health care professional whose duties include positioning and attending to patients undergoing nuclear medicine procedures, operating imaging devices (scintillation cameras and rectilinear scanners) under the direction of the nuclear medicine physician, preparing radiopharmaceuticals for administration to patients, making dose calculations for in vivo procedures, performing quality control procedures, and utilizing a knowledge of radiation physics and radiation safety to minimize the radiation exposure to patients, to the technologist and coworkers, and to the public. There are currently three organizations that certify nuclear medicine technologists: the American Registry of Radiologic Technologists (ARRT), the American Society of Clinical Pathologists (ASCP), and the Nuclear Medicine Technology Certification Board (NMTCB). Individuals certified by the ARRT are designated RT(N)(ARRT); those certified by the ASCP are designated NM(ASCP); and those certified by the NMTCB are designated CNMT.

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resonance [rez´o-nans]

1. the prolongation and intensification of sound produced by transmission of its vibrations to a cavity, especially such a sound elicited by percussion. Decrease of resonance is called dullness; its increase, flatness.

2. a vocal sound heard on auscultation.

3. mesomerism.

amphoric resonance a sound resembling that produced by blowing over the mouth of an empty bottle.

nuclear magnetic resonance see nuclear magnetic resonance.

skodaic resonance increased percussion resonance at the upper part of the chest, with flatness below it; heard over a large pleural effusion or area of consolidation.

tympanic resonance tympanitic resonance (def. 2).

tympanitic resonance

1. the peculiar sound elicited by percussing a tympanitic abdomen.

2. the drumlike reverberation of a cavity full of air; called also tympanic resonance.

vocal resonance (VR) the sound of ordinary speech as heard through the chest wall.

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nuclear magnetic resonance,

n See magnetic resonance imaging.

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nuclear magnetic resonance

See Magnetic resonance imaging, NMR.

Nuclear magnetic resonance

Diagnostic NM  

• In vivo–eg injection of radiocontrast to detect an ↑/↓ in local 'signal'–uptake in suspected bone metastases

• In vitro–assays of clinical specimens, eg radio immunoassay–RIA for various hormones, eg human chorionic gonadotropin–β-HCG, insulin, and TSH

Therapeutic NM Radiation oncology Administration of a 'hot' isotope to sterilize a particular area, and prevent malignant cells from growing & dividing

Note: RIAs are being replaced by ELISAs, which are easier to perform, the reagents are more easily stored, and do not have the problems inherent in using and disposing of radioactive waste; nuclear medicine also encompasses in vivo diagnostics in the form of scintillation counters to 'scan' various body regions for the presence of increased uptake of radionuclides, which when focal, implies primary neoplasia or metastases