Apparatus and method for in-vivo fat and iron content measurement

Abstract

An apparatus for measuring liver fat content and/or iron content non-invasively in vivo using unilateral NMR technology is disclosed. The apparatus comprises a unilateral NMR probe positioned against or in the proximity of the body. The probe generates static and RF magnetic fields to measure NMR signals at selected depths into the body. The apparatus further comprises a unilateral magnet and a unilateral antenna placed between a magnet and the body or around the magnet. The unilateral antenna is used to attain NMR signals. The measurement of NMR signals at a single position with a single frequency determines fat content on a specific volume inside the liver. The measurement of NMR signals at a single position with two or more frequencies determines iron content on a specific volume inside the liver.

What is claimed is: 
     
         1 . An apparatus for measuring liver fat fraction non-invasively in vivo using unilateral NMR technology, the apparatus comprising:
 a unilateral NMR probe positioned against or in the proximity to a patient's body, wherein the probe generates a sensitive volume inside the body;   whereas the probe consists of an open magnet and a unilateral antenna placed between a magnet and the body or around the magnet,   wherein the unilateral probe is used to measure NMR signals at selected depths into the body, and wherein the measurement of NMR signal at a single position with a single frequency determines fat content on a specific volume inside the liver.   
     
     
         2 . The apparatus of  claim 1 , wherein the fat content in the liver is measured using NMR relaxation times and signal amplitude from multi-pulse sequences. 
     
     
         3 . The apparatus of  claim 1 , further measures diffusion coefficients of tissue as means to discriminate within various tissues using a unilateral NMR probe. 
     
     
         4 . The apparatus of  claim 3 , wherein the diffusion coefficient is determined using at least two pulse spacing in a multi-pulse NMR sequence. 
     
     
         5 . The apparatus of  claim 1 , wherein the probe is positioned against or in the proximity of the body using a unilateral electromagnet. 
     
     
         6 . The apparatus of  claim 1 , wherein the probe is positioned against or in the proximity of the body using a unilateral permanent magnet. 
     
     
         7 . The apparatus of  claim 1 , wherein the probe is positioned against or in the proximity of the body using a combination of permanent and electromagnets. 
     
     
         8 . The apparatus of  claim 1 , wherein the unilateral antenna is mounted under a table to measure fat content. 
     
     
         9 . An apparatus for measuring liver iron content using unilateral NMR technology, the apparatus comprising:
 a unilateral NMR probe positioned against or in the proximity to a patient's body, wherein the probe generates a sensitive volume inside the body;   whereas the probe consists of an open magnet and a unilateral antenna placed between a magnet and the body or around the magnet,
 wherein the probe generates static and RF magnetic fields to measure the NMR signal at selected depths into the body, and wherein the measurement of NMR signal at a single position with two or more frequencies determines iron content on a specific volume inside the liver. 
   
     
     
         10 . The apparatus of  claim 9 , wherein the iron content in the liver is measured using multi-pulse sequences of relaxation times and signal amplitude at two or more frequencies. 
     
     
         11 . The apparatus of  claim 9 , wherein the probe is positioned against or in the proximity of the body using a unilateral electromagnet. 
     
     
         12 . The apparatus of  claim 9 , wherein the probe is positioned against or in the proximity of the body using a unilateral permanent magnet. 
     
     
         13 . The apparatus of  claim 9 , wherein the probe is positioned against or in the proximity of the body using a combination of permanent and electromagnets. 
     
     
         14 . The apparatus of  claim 9 , wherein the unilateral antenna is mounted under a table to measure iron content. 
     
     
         15 . A method of measuring liver fat fraction using unilateral NMR technology, the method comprises:
 generating a sensitive volume inside the body; and   attaining a NMR signal,   wherein static and RF magnetic fields are measures using the NMR signal at selected depths into the body at a single position with a single frequency determines fat content on a specific volume inside the liver.   
     
     
         16 . A method of measuring liver iron content using unilateral NMR technology, the method comprises:
 generating a sensitive volume inside the body; and   attaining a Nuclear Magnetic Resonance (NMR) signal,   wherein static and Radio Frequency (RF) magnetic fields are measures using the NMR signal at selected depths into the body at a single position with two or more frequencies determines iron content on a specific volume inside the liver.