Role of Duplex Doppler in Assessment

Summary and ConclusionThe accuracy of various Doppler parameters of portal circulation in the diagnosis of relevant portal hypertension was prospectively validated.Duplex ultrasound allows direct access to portal venous and hepatic vein haemodynamics. This method has been accepted as a reliable procedure to detect portal and splenic venous thrombosis, Budd Chiari’s syndrome, portosystemic collateralization and changes in the portal venous blood direction with a high rate of sensitivity.Recently, it was found that Doppler is a valuable tool for follow up in medical and surgical treatment of portal hypertension.Also, some patients look too good to have varices, as they have no other stigmata of cirrhosis after their initial variceal bleeding, and have no definable risk factors for liver disease. Doppler ultrasound after portal vein may strongly suggest the diagnosis.The aim of this work was to assess he clinical role of duplex Doppler techniques in evaluation of the portal venous system in different pathological conditions.The study included 50 patients. Control group of 15 volunteers, with non of them had history or clinical findings of liver diseases, and normal function tests, was used to assess the normal sonographic appearance and normal blood flow in the portal venous system.The patients were divided according to Child-Pough classification into three groups:Grade A group: score between 5 – 6 points (28 patients)Grade B group: score between 7 – 9 points (14 patients)Grade C group: score more than 9 points (8 patients)All patients were subjected to the following:1- Full clinical history and examination.2- Laboratory investigation3- Ultrasonography in the form of :a. B-mode ultrasound examinationb. Doppler US examination4- Biopsy: were available for only 11 patients, So, we excluded it from the study.All obtained data for the patients were tabulated and compared with each other and with control group, So as to assess the role of duplex Doppler in evaluation of portal venous system.In our study, bilharziasis was responsible for 58% of cirrhosis of the cases (29 patients), HBV for 11 patients, HCV for 20 patients. 6 patients had other cause while 8 had more than one cause.In B-mode study of the liver, nodular surface was detected in 21 patients (42%), 8 of them where 100% of grade C.Caudate lobe hypertrophy was present in 32 of the patients (64%) 18 patients (64.29%) of grade A, 11 patients (78.57%) of Grade B and 3 patients (37.5%) of Grade C group.Liver echogenecity was present in 40 patients (80%) although it was found in 20% of the controls. All patients of group C (100%) were having increasing echogenecity.From associated findings and complications found during ultrasound examination, ascitis and varices were the most marked as they represented (32%) of all patients (each of them). They were mostly obvious in Child C group as they represented 100% and 50% in row.B-mode examination detected that liver span in midclavicular line measured craniocaudaly in controls was 10.9 1.5 cm, while it was 12.8  1.5 cm in Child A group, 12.0  1.7 in Child B and 12.1  2.1 in Child C. Also splenic span was 8.2  1.1 cm in control group, increased markedly in Child A to (13.4  4.8 cm) and 10.8  2.4 in Child B and return near normal in Child C group (9.11.9 cm).Mean portal vein diameter was 10.8  1.7 m in controls while it exceeds 13 mm (14.2  2.1 mm) in patients. It was 13.1  2.5 Child A, 14.3  2.1 Child B and 14.3  2.1 Child C. While the mean value of cross sectional area of portal vein was 1.05  0.24 cm2 in Child A group, 1.47  0.46 in Child B and 1.55  0.48 in Child C. This was more than the control group which was (0.98  0.29 cm2).We also found that the mean velocity of blood flow of normal portal vein was 25.8  5.2 sd cm/sec. which show marked decrease up to 18.0  5.7 cm/sec. in Child A group with further decrease in group B 15.7  9.2 cm/sec., and 10.6  11.4 cm/sec. in group C. wide range is seen in Child C group and minus results mean reversed flow.Mean blood flow volume in normal portal vein was 822  178 SD ml/min. which shows some increase to 818  197 ml/min. in Child A group. Then, gradually decreased to 632  107 ml/min. in grade B, with further decrease to 435  211 ml/min. is seen in Child C group.At calculation of congestion index (CI), we found that normal congestion index of the portal vein was 0.069  0.18 cm x sec. It gradually increases from 0.172 in grade A group, 0.202 in grade B group. Up to 0.248 in grade C group. We also detected that control group didn’t all show hepatopetal flow as 3 persons representing (20%) show bidirectional flow.Hepatopetal flow was found in only (50%) of all the patients, bidirectional flow in 9 patients (18%), hepatofugal flow 12 patients (24%) and no flow in 4 patients (8%)On examining the spectral Doppler US grades of hepatic vein and classifying it according to Farrant, (1997) we found that only 10 persons of the normal volunteers representing 66% showed complete normal modulation. One person showed grade 5 curve, 3 persons showed grade 4 curve and one showed grade 3 waveform. Also, we found gradual change from grade 6 waveform (normal) to grade 1 (no detectable modulation) is detected in all Child groups and no cases with grade 5 or 6 could be seen in Child C group.We concluded that, we can depend on congestion index in diagnosis and grading of portal hypertension as it is less than 0.1 in normal persons with gradual increase according to Child–Pough grades. So, we can depend on congestion index and portal vein velocity as an accurate parameters in diagnosis of portal hypertension.