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In radiology, a region in an image caused by an absorber of lower x-ray attenuation than its surrounding tissues; in general, the opposite of opacity.
[fr. L. lucens, shining, fr. luceo, to shine]
References in periodicals archive ?
In asthmatic group of the present study, half of them are radiologically normal and rest half shows increased lucency and low flat diaphragm.
Radiographically, occurrence of signs of osteomyelitis (bone lucency, periosteal reactions) did not differ significantly among groups (Table 1).
Shaft fractures may not be seen on x-rays in the first 3 weeks, but a periosteal reaction or linear lucency near the symptomatic area may be noticeable on radiographs taken at a later date.
When seen in the cortex of the long bones, the region of osteolysis appears as a wedge-shaped lucency, the characteristic "blade of grass" appearance.
X-rays may show an irregular lucency of the capitellum and sometimes loose bodies within the joint.
There is discussion regarding the "halo" sign, density, opacity or lucency, form, orientation and size.
Computer analysis of periventricular lucency on the CT scan.
On Voiding Cystourethrogram, it appears as a round to oval lucency near the trigone of bladder.
7) Among subtypes of intramedullary osteosarcoma, osteoblastic osteosarcoma generally demonstrates the greatest degree of sclerosis/osteoid formation, while chondroblastic and fibroblastic osteosarcomas may demonstrate areas of lucency juxtaposed with areas of osteoid production.
When this lucency is not present, the lateral fourth of the head is used.