A fractal analysis of bone phantoms from digital images / 대한구강악안면방사선학회지
Korean Journal of Oral and Maxillofacial Radiology
;
: 33-40, 2005.
Artigo
em Coreano
| WPRIM
| ID: wpr-100232
ABSTRACT
PURPOSE:
(1) To analyse the effect of exposure time, ROI size and one impact factor in the image processing procedure on estimates of fractal dimension; and (2) to analyse the correlated relationship between the fractal dimension and the Cu-Eq value (bone density). MATERIALS ANDMETHODS:
The cylindric bone phantoms of 6 large and 5 small diameter having different bone densities respectively and human dry mandible segment with copper step wedge were radiographed at 1.0 and 1.2 sec esposure (70 kVp, 7 mA) using one occlusal film and digitized. Eleven rectangular ROIs from 11 cylindric bone phantoms and 4 rectangular ROIs from cortical, middle, periodontal regions, and socket of bone were selected. Gaussian blurred Image was subtracted from original image of each ROI and multiplied respectively by 1, 0.8, and 0.5, and then the image was made binary, eroded and dilated once, and skeletonized. The fractal dimension was calculated by means of a box counting method in the software ImageJ.RESULTS:
The fractal dimension was decreased gradually with continued bone density decrease showing strong correlations (bone phantom; r> 0.87, bone; r> 0.68) under 70 kVp 1.0 sec M = 0.8. Fractal dimensions showed the significant differerence (p 0.05) under 1.0 sec exposure.CONCLUSIONS:
Exposure time, ROI size, and modifying factor during subtracting could become impacting on the results of fractal dimension. Fractal analysis with thoroughly evaluated method considering the various impacting factors on the results could be useful in assessing the bone density in dental radiography.
Texto completo:
DisponíveL
Índice:
WPRIM (Pacífico Ocidental)
Assunto principal:
Esqueleto
/
Radiografia
/
Radiografia Dentária
/
Densidade Óssea
/
Fractais
/
Citocromo P-450 CYP1A1
/
Cobre
/
Mandíbula
Tipo de estudo:
Estudo diagnóstico
Limite:
Humanos
Idioma:
Coreano
Revista:
Korean Journal of Oral and Maxillofacial Radiology
Ano de publicação:
2005
Tipo de documento:
Artigo
Similares
MEDLINE
...
LILACS
LIS