Noninvasive evaluation of mineral content of bone without use of ionizing radiation.

Abstract

The mineral content of bone can be quantified by recording a 31P NMR spectrum while the bone is stationary. The quantity of mineral in the bone is determined from the spectrum with a reference standard by comparison of relative peak areas. The phosphate of bone mineral is readily distinguished from inorganic phosphate and phosphorylated metabolites dissolved in cytosol and from the head groups of phospholipids in membranes. The technical feasibility of constructing a cost-effective instrument for analysis of bone mineral content in the extremities is demonstrated. The possible utility of such a noninvasive assay for detecting osteoporosis and for monitoring the progress of treatment is discussed.

Water Content Measured by Proton-Deuteron Exchange NMR Predicts Bone Mineral Density and Mechanical Properties

“…(25) Alternatively, treatment with antiresorptives such as bisphosphonates has been demonstrated to increase DMB. (26) To date, 31 P NMR is perhaps the only nondestructive and potentially noninvasive method for measuring mineral content either in bulk (27)(28)(29) or in a spatially resolved manner by imaging. (30 -33) However, the large linewidths on the order of 3-4 kHz (corresponding to T 2 ϳ 100 s) and long spin-lattice relaxation times (T 1 ϳ 20 -60 s) complicate imaging at a resolution sufficient to determine true DMB, which requires accurate volume measurements.…”

Clinical chemistry

“…If this is proven and cost reduced it could have a significant impact on the detection and therapy of cancer. Magnetic resonance imaging (MRI) has become a promising technology in medicine but it is not considered part of clinical chemistry (40)(41)(42). Two-dimensional shift correlated NMR has found some recent application in toxicology while considerable attention is focused on 31P NMR for metabolic studies and bone evaluation (43)(44)(45).…”

Postprocessing method to segregate and quantify the broad components underlying the phosphodiester spectral region of in vivo31P brain spectra

“…The powder pattern lineshape is better defined at higher field strengths (>4 T) or with 1 H decoupling at lower field strengths (≤2 T). Depending on the localization scheme or lack of same, an in vivo 31 P brain spectrum also may contain a fourth component from calcium hydroxyapatile in bone that is much broader and more symmetric relative to the powder pattern (32, 42, 43).…”