Linked Life Data

3862656

Source:http://linkedlifedata.com/resource/pubmed/id/3862656

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1985-11-14
pubmed:abstractText
In the radiographic assessment of primary musculoskeletal tumors, it is important for therapy planning to accurately define the extent of a tumor. Using a double spin-echo pulse sequence, the T1 and T2 relaxation times and relative hydrogen densities of several neoplastic tissues and of several normal tissues in four patients were measured. Neoplasms measured included one fibrosarcoma, two osteosarcomas, and one giant cell tumor. Normal tissues measured included normal muscle, fat, and bone marrow. Using a mathematical model of the double spin-echo pulse sequence, the intensity difference between each tumor and each normal tissue for multiple values of TR and TE was calculated. These calculated intensity differences were then used to plot isodifference contour curves for each tissue pair. These plots enabled us to pick combinations of TR and TE that optimized the signal difference between tumor and normal tissue. When comparing tumor with predominantly fatty tissue such as marrow or subcutaneous fat, optimal signal difference in our imager occurred at a TR of 600 to 800 msec and a very short TE. When comparing tumor with muscle, optimal signal difference occurred with very long TR times, and TE times ranging from 30 to 90 msec. These preliminary results suggest that an optimal scanning protocol for primary musculoskeletal tumors should contain at least two different pulse sequences with widely separated TR values (500 and 2000 msec in our instrument), and short to intermediate values of TE (28 and 56 msec in our instrument). It is believed that analysis of isodifference contour plots is a useful method for optimizing intensity differences between any two tissue types.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0020-9996
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
492-7
pubmed:dateRevised
2009-11-11
pubmed:meshHeading
pubmed:year
1985
pubmed:articleTitle
Theoretical considerations for optimizing intensity differences between primary musculoskeletal tumors and normal tissue with spin-echo magnetic resonance imaging.
pubmed:publicationType
Journal Article