3D Sonographic Measurement of Volumetric Flow in Transjugular Intrahepatic Porto-Systemic Shunts

Study Overview
=================
Brief Summary
-----------------
To determine if ultrasound measurements can accurately measure the blood pressure of flow across a stent that has been placed in a portal vein to reduce portal vein pressure known as Transjugular Intrahepatic Porto-Systemic shunts or TIPS.

Detailed Description
-----------------
To determine if 3D ultrasound measurements can accurately measure the pressure of blood flow across a stent that has been placed in a portal vein. This has been done in order to reduce portal vein pressure. These shunts are known as Transjugular Intrahepatic Porto-Systemic shunts or TIPS.

Official Title
-----------------
3D Sonographic Measurement of Volumetric Flow in Transjugular Intrahepatic Porto-Systemic Shunts

Conditions
-----------------
Portal Hypertension, Liver Disease

Intervention / Treatment
-----------------
* Procedure: Volumetric Flow in TIPS


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Male and female 18 years of age and older Have an existing TIPS (Transjugular intrahepatic porto-systemic shunt) Have an ultrasound ordered by your physician to evaluate your TIPS. Able to read, understand and sign informed consent Exclusion Criteria: Under 18 years of age Cannot be pregnant

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Health Services Research
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Volumetric Flow in TIPS<br>Subjects who have TIPS (transjugular intrahepatic porto-systemic shunts) have measurements taken to determine if someone has increased blood pressure in the portal vein of the liver (portal hypertension). Subjects who have a TIPS receive clinical ultrasounds every 3 months to determine if the TIPS is working properly. | Procedure: Volumetric Flow in TIPS<br>* Subjects who have a TIPS (transjugular intrahepatic portal-systemic shunt) for portal hypertension will undergo a clinical 3D ultrasound to determine if the TIPS is working properly. Additional ultrasounds will be obtained during the subject's clinically ordered ultrasound(s). These measurements will be taken by using a second ultrasound probe (plastic hand held device that is rubbed along the subject's abdomen). 15 minutes will be added to your clinically ordered exams that are completed 4 times a year.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Estimate portal blood flow within a transjugular portosystemic shunt | To determine the number of volumes to achieve a specified variance in the measurement and to determine the reproducibility of the volume flow measurements taken at multiple locations within the stent (3 locations with 3 measurements each for a total of 9 acquisitions). The physicians will measure volume flow rate three times at three different locations in the shunt (that being proximal, medial and distal) to determine the reproducibility of the flow estimate. | 4 years |