Method for thoracic vertebral bone density measurement by thoracic quantitative computed tomography

Abstract

A technique for measuring thoracic vertebral bone density (BMD) and coronary calcium score (CCS). Representatively, BMD was measured and averaged at three consecutive thoracic spines (3T) starting from the left main coronary artery caudally and averaging the results of the measurements at the first, second and third spine regions to obtain a thoracic trabecular bone mineral density measurement. The “reference”, as the 3T BMD value of 30 year old and the piBMD (predicted individual BMD (piBMD) were developed. Based on the “reference”, and piBMD, T and Z score of 3T formula were derived in both genders. The new calibration phantom of TQCT and LQCT was designed. The ratios of CTHU/mg/cc were obtained with varying scanners, which were used to translate the CTHU to density units (mg/cc) in BMD and CCS mass measurement. A processor capable of quantitating both BMD and CCS burden was designed. In image without a calibration phantom, formulas were created to quantitate BMD with a high precision.

What is claimed is: 
     
         1 . A method comprising:
 obtaining an image of a spine region at a level comprising a left main coronary artery;   identifying a portion of the image comprising a body location level comprising the left main coronary artery;   identifying a cerebral center at a spine region containing the left main coronary artery;   measuring a bone mineral density at a first spine region containing the left main coronary artery;   measuring a bone mineral density at a second spine region following the spine region containing the left main coronary artery;   measuring a bone mineral density at a third spine region following the second spine region containing the left main coronary artery; and   averaging the results of the measurements at the first, second and third spine regions to obtain a thoracic trabecular bone mineral density measurement.   
     
     
         2 . The method of  claim 1 , wherein the image is a computed tomography (CT) image containing a heart and a thoracic spine. 
     
     
         3 . The method of  claim 1 , wherein the image is a computed tomography (CT) image containing the left main coronary artery and at least three thoracic spines. 
     
     
         4 . The method of  claim 1 , wherein the image is a computed tomography (CT) image obtained at a temporal resolution of less than 400 milliseconds/rotation. 
     
     
         5 . A system comprising:
 a computing device for averaging the results of a measurement of bone mineral density at a first spine region, a second spine region and a third spine region to obtain a (3T) thoracic trabecular bone mineral density measurement.   
     
     
         6 . A machine readable medium containing a set of instructions that when executed cause a computing device to perform a method comprising:
 averaging the results of a measurement of bone mineral density at a first spine region, a second spine region and a third spine region to obtain a thoracic trabecular bone mineral density measurement.