The Use and Reproducibility of Duplex Ultrasound to Provide Indices of Left Common Iliac Vein Diameter

Study Overview
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Brief Summary
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The goal of this feasibility/pilot study is to investigate whether or not vascular ultrasound can be used to aid the diagnosis of May Thurner Syndrome, in adult patients presenting to the vascular department with unexplained left leg swelling. The main research objective it aims to answer are: The diameter variation of the left common iliac vein based on posture, using duplex ultrasound. To determine inter- and intra-observer variation of the diameter measurement of the left common iliac vein using duplex ultrasound. Participants will have an ultrasound scan performed on their abdomen by three different clinical vascular scientists, and will have each scan performed whilst lying supine on an examination couch and again when the couch is tilted to 45 degrees. Researchers will compare the results of symptomatic patients to asymptomatic patients, to see if there is a difference in the diameter of the left common iliac vein between these two groups.

Official Title
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The Use and Reproducibility of Duplex Ultrasound to Provide Indices of Left Common Iliac Vein (CIV) Diameter, to Aid and Improve the Diagnosis of May Thurner Syndrome (MTS) in Patients Presenting With Unexplained Left Leg Swelling

Conditions
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May-Thurner Syndrome

Intervention / Treatment
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* Diagnostic Test: Duplex ultrasound


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Participant has the capacity to consent Participant is required to have a vascular ultrasound scan in the vascular ultrasound department Participant is 18 years of age or older at the start of the study. Exclusion Criteria: Previous iliac vein intervention or treatment for iliac vein disease Previous diagnosis of iliac vein thrombus Pregnancy Unable to provide appropriate informed consent The participant does not require a vascular ultrasound as part of their routine care Under 18 years of age at the start of the study

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Symptomatic Group<br>Participants who are suffer from unexplained left leg swelling. | Diagnostic Test: Duplex ultrasound<br>* Vascular ultrasound scan of the left common iliac vein<br>|
| Other: Asymptomatic Group<br>Participants who do not suffer from unexplained left leg swelling | Diagnostic Test: Duplex ultrasound<br>* Vascular ultrasound scan of the left common iliac vein<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Left common iliac vein diameter | The diameter measurement (in mm) of the left common iliac vein in adults referred to the vascular ultrasound department. | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Inter-and intra-operator variation of the diameter measurement of the left common iliac vein | The inter- and intra-operator variation of the diameter measurement of the left common iliac vein using duplex ultrasound, in adults referred to the vascular ultrasound department. | 6 months |