Optimising the scan delay for arterial phase imaging of the liver using the bolus tracking technique
	    		
		   		
	    	
    	
    	
   		
        
        	
        	
        	
        		- Author:
	        		
		        		
		        		
			        		Chan RS
			        		
			        		;
		        		
		        		
		        		
			        		Kumar G
			        		
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			        		Abdullah BJJ
			        		
			        		;
		        		
		        		
		        		
			        		Ng KH
			        		
			        		;
		        		
		        		
		        		
			        		Vijayananthan A
			        		
			        		;
		        		
		        		
		        		
			        		Mohd. Nor H
			        		
			        		;
		        		
		        		
		        		
			        		Liew YW
			        		
			        		
		        		
		        		
		        		
		        		
		        		
			        		
			        		
		        		
	        		
        		 
        	
        	
        	
        		- Publication Type:Journal Article
 
        	
        	
        		- Keywords:
        			
	        			
	        				
	        				
			        		
				        		Arterial phase imaging of the liver, bolus tracking technique
			        		
			        		
	        			
        			
        		
 
        	
            
            
            	- From:Biomedical Imaging and Intervention Journal
	            		
	            		 2011;7(2):1-10
	            	
            	
 
            
            
            	- CountryMalaysia
 
            
            
            	- Language:English
 
            
            
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		        	Abstract:
			       	
			       		
				        
				        	Objective: To optimize the delay time before the initiation of arterial phase scan in the detection of focal liver lesions in contrast enhanced 5 phase liver CT using the bolus tracking technique.
Patients and Methods: Delay - the interval between threshold enhancement of 100 hounsfield unit (HU) in the abdominal aorta and commencement of the first arterial phase scan. Using a 16 slice CT scanner, a plain CT of the liver was done followed by an intravenous bolus of 120 ml nonionic iodinated contrast media (370 mg I/ml) at the rate of 4 mL/s. The second phase scan started immediately after the first phase scan. The portal venous and delay phases were obtained at a fixed delay of 60 s and 90 s from the beginning of contrast injection. Contrast enhancement index (CEI) and subjective visual conspicuity scores for each lesion were compared among the three groups.
Results: 84 lesions (11 hepatocellular carcinomas, 17 hemangiomas, 39 other hypervascular lesions and 45 cysts) were evaluated. CEI for hepatocellular carcinomas appears to be higher during the first arterial phase in the 6 seconds delay group. No significant difference in CEI and mean conspicuity scores among the three groups for hemangioma, other hypervascular lesions and cysts.
Conclusion: The conspicuity of hepatocellular carcinomas appeared better during the early arterial phase using a bolus tracking technique with a scan delay of 6 seconds from the 100 HU threshold in the abdominal aorta.
				        	
				        
				    
			    
 
	        
	        
	        	- Full text:W020150914376165241519.pdf