A Novel Method for Estimation of Femoral Neck Bone Mineral Density Using Forearm Images from Peripheral Cone Beam Computed Tomography

Abstract

Abstract:The main goal of osteoporosis treatment is prevention of osteoporosis-induced bone fracture. Dual-energy X-ray absorptiometry (DXA) and quantitative computed tomographic imaging (QCT) are widely used for assessment of bone mineral density (BMD). However, they have limitations in patients with special conditions. This study evaluated a method for diagnosis of osteoporosis using peripheral cone beam computed tomography (CBCT) to estimate BMD. We investigated the correlation between the ratio of cortical and total bone areas of the forearm and femoral neck BMD. Based on the correlation, we established a linear transformation between the ratio and femoral neck BMD. We obtained forearm images using CBCT and femoral neck BMDs using dual-energy X-ray absorptiometry (DXA) for 23 subjects. We first calculated the ratio of the cortical to the total bone area in the forearm from the CBCT images, and investigated the relationship with the femoral neck BMDs obtained from DXA. Based on this relationship, we further investigated the optimal forearm region to provide the highest correlation coefficient. We used the optimized forearm region to establish a linear transformation of the form to estimate femoral neck BMD from the calculated ratio. We observed the correlation factor of r = 0.857 (root mean square error = 0.056435 g/cm 2 ; mean absolute percentage error = 4.5105%) between femoral neck BMD and the ratio of the cortical and total bone areas. The strongest correlation was observed for the average ratios of the mid-shaft regions of the ulna and radius. Our results suggest that femoral neck BMD can be estimated from forearm CBCT images and may be useful for screening osteoporosis, with patients in a convenient sitting position. We believe that peripheral CBCT image-based BMD estimation may have significant preventative value for early osteoporosis treatment and management.

A Pilot Study on Hip Bone Mineral Densities Estimation from Forearm CBCT images

“…In [26], bicortical thickness of the distal radius was positively correlated with femoral neck BMD. Recently, it was reported that a femoral neck BMD is associated with the relative cortical bone area of forearm [17]. All these studies reflect that the bones in forearm and hip are correlated.…”

“…In [23], a feasibility study was conducted that forearm BMD using DXA may predict hip osteoporosis. In [17,[24][25][26], the investigators showed that some parameters from the cortical bone in distal radius and ulna on anteroposterior radiograph could reflect the femoral neck BMD. In [24], the distal radius BMD was correlated with the ratio of the outside cortical shell diameter to the inside cortical shell diameter at the metaphyseal/diaphyseal junction.…”

“…Furthermore, it is difficult to diagnose osteoporosis based on hip bone BMD in patients who have undergone hip replacement. We recently found a strong correlation between relative cross-sectional area of forearm cortical bone and femoral neck BMD [17]. This correlation reflects that the quality and loading properties of the femur and radius are related because they are both appendicular bones, and the relative cross-sectional area of forearm cortical bone can predict the BMD value of the femoral neck: the BMD of the femoral neck can be estimated by scanning a forearm using peripheral cone beam computed tomography (CBCT) in a convenient sitting position without X-ray exposure to the hip region that includes the genital organs.…”

Scattered image artifacts from cone beam computed tomography and its clinical potential in bone mineral density estimation

“…Then, assuming the CBCT detector is optimized with the corresponding thickness, the radiation dose can be further reduced up to 1/462 times, which is approximately equivalent to 0.3 µSv. Furthermore, the forearm CBCT images can be used for estimating BMD values of lumbar spine and hip bone with a linear regression (Jeong et al 2016 ). Then, for lumbar spine and/or hip bone BMD, the effective radiation dose from CBCT is less than that from DXA, 2.2 µSv (Thomas et al 2006 ).…”

“…One of the advantages in our approach is that only a forearm needs to be exposed via X-ray for BMD assessment of a lumbar spine and/or hip bones since the forearm CBCT images can be used for estimating BMD values of a lumbar spine and hip bones (Jeong et al 2016 ). On the other hand, traditional approaches using DXA and QCT require X-ray exposure in the entire axial skeleton near a lumbar spine or a hip.…”