In both cases, the volume that is extracted must be able to follow the fiber bundles across the volume. High contrast makes segmentation easier, especially when color information is available. In addition, the need for fixation must also be addressed. It has been shown that soft tissue fixation in formalin causes shrinkage, altering the structure of the original tissue. Some typical values of contraction for different fixation are: formalin (5% - 10%), alcohol (10%), bouin (<5%).Imaging methods used in ECM visualization and their properties. Disorders
Soft tissue disorders are medical conditions affecting soft tissue. Often soft tissue injuries are some of the most chronically painful and difficult to treat because it is very difficult to see what is going on under the skin with the soft connective tissues, fascia, joints, muscles and tendons. Musculoskeletal specialists, manual therapists and neuromuscular physiologists and neurologists specialize in treating injuries and ailments in the soft tissue areas of the body. These specialized clinicians often develop innovative ways to manipulate the soft tissue to speed natural healing and relieve the mysterious pain that often accompanies soft tissue injuries. This area of expertise has become known as soft tissue therapy and is rapidly expanding as the technology continues to improve the ability of these specialists to identify problem areas more quickly. A promising new method of treating wounds and soft tissue injuries is via platelet growth factor (PGF).There is a close overlap between the term "soft tissue disorder" and rheumatism. Sometimes the term "soft tissue rheumatic disorders" is used to describe these conditions.
Fung-elastic material
Fung developed a constitutive equation for preconditioned soft tissues which is 

  
    
      
        W
        =
        
          
            1
            2
          
        
        
          [
          
            q
            +
            c
            
              (
              
                
                  e
                  
                    Q
                  
                
                −
                1
              
              )
            
          
          ]
        
      
    
    {\displaystyle W={\frac {1}{2}}\left[q+c\left(e^{Q}-1\right)\right]}
  with

  
    
      
        q
        =
        
          a
          
            i
            j
            k
            l
          
        
        
          E
          
            i
            j
          
        
        
          E
          
            k
            l
          
        
        
        Q
        =
        
          b
          
            i
            j
            k
            l
          
        
        
          E
          
            i
            j
          
        
        
          E
          
            k
            l
          
        
      
    
    {\displaystyle q=a_{ijkl}E_{ij}E_{kl}\qquad Q=b_{ijkl}E_{ij}E_{kl}}
  quadratic forms of Green-Lagrange strains 
  
    
      
        
          E
          
            i
            j
          
        
      
    
    {\displaystyle E_{ij}}
   and 
  
    
      
        
          a
          
            i
            j
            k
            l
          
        
      
    
    {\displaystyle a_{ijkl}}
  , 
  
    
      
        
          b
          
            i
            j
            k
            l
          
        
      
    
    {\displaystyle b_{ijkl}}
   and 
  
    
      
        c
      
    
    {\displaystyle c}
   material constants.