Diagnostic efficacy of Hounsfield units in spine CT for the assessment of real bone mineral density of degenerative spine: correlation study between T-scores determined by DEXA scan and Hounsfield units from CT.
Acta Neurochir (Wien)
; 158(7): 1421-7, 2016 07.
Article
en En
| MEDLINE
| ID: mdl-27177734
BACKGROUND: Dual-energy X-ray absorptiometry (DEXA) scan is an easy and cost-effective method of assessing bone mineral density (BMD). However, in patients with degenerative changes of the spine, overestimation of T-score on DEXA scan can occur despite low BMD during pedicle screw placement in spine surgery. The goal of this study is to assess BMD using Hounsfield unit (HU) measurements from computed tomography (CT) and to correlate these with DEXA-assessed T-scores in non-degenerative and degenerative patients. METHODS: This study included 80 non-degenerative and 30 degenerative patients who underwent DEXA and spine CT assessment. The HU value on the mid-body axial images of CT and DEXA-assessed T-scores were measured from the L1-4 vertebrae. RESULTS: In the non-degenerative group, HU values had a strong positive correlation with BMD and T-score, exhibiting correlation coefficients (r) greater than 0.7: the r-value (p value) between HU and T-score of the L1 vertebra was 0.701 (<0.001); 0.709 (<0.001) for L2; 0.709 (<0.001) for L3; 0.649 (<0.001) for L4; and 0.734 (<0.001) for L1-4. BMD assessed as +100 HU matched a T-score of -2.0 while +150, +200 HU matched T-scores of -1.0, 0.0. The differences were significant (p < 0.001). In the degenerative group, there was a weak positive correlation with r of approximately 0.4: the r-value (p value) was 0.300 (0.104); 0.457 (0.013); 0.433 (0.017); 0.447 (0.013) at each segment and 0.398 (0.031) for L1-4. CONCLUSIONS: HU values provide a meaningful assessment of BMD and have a strong correlation with T-score. However, in degenerative patients, the T-score tended to be higher than the actual BMD. BMD assessment using HU might be helpful in predicting real BMD in patients undergoing instrumentation surgery with degenerative changes of the spine.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Osteoporosis
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Tomografía Computarizada por Rayos X
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Absorciometría de Fotón
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Densidad Ósea
Tipo de estudio:
Diagnostic_studies
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Evaluation_studies
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Prognostic_studies
Límite:
Adult
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Aged
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Aged80
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Female
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Humans
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Middle aged
Idioma:
En
Revista:
Acta Neurochir (Wien)
Año:
2016
Tipo del documento:
Article
País de afiliación:
Corea del Sur
Pais de publicación:
Austria