Doppler sonography[18, 27, 30–32, 34, 78–101]
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- noninvasive
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- no standardized guidelines
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- without ionizing radiation
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- operator dependent
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- less expensive
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- time consuming (60 to 120 minutes)
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- high resolution
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- blinding procedures are challenging
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- real time information
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- cannot perform global view of the veins (limited window)
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- sensitive to detect flow changes, intra- and extra-luminal abnormalities
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- misidentification of the veins
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- ability to measure velocity
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- influenced by hydration status
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- possible control of respiratory phases
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Magnetic resonance venography[10, 30, 31, 34, 42, 43, 102]
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- noninvasive
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- no real time information
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- without ionizing radiation
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- cannot detect intra-luminal abnormalities
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- well established method
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- low specificity of conventional MRV techniques
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- operator independent
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- influenced by hydration status
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- less time consuming than DS
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- azygos vein examination needs technical improvements due to important artifacts (breathing, heart movements)
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- provide global view of intra- and extra-cranial venous system
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- underestimates the vascular caliber
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- easy to blind
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- “snapshot” nature
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- ability to measure flow and velocity with advanced technique (phase contrast MRV)
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- global view of collateral veins
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- can be performed without contrast (pregnancy, allergy)
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Computed tomography venography[5, 103, 104]
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- noninvasive
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- ionizing radiation
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- less expensive and time consuming than MRV
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- no real time information
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- better spatial resolution than MRV
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- cannot detect intra-luminal abnormalities
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- global view of veins
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- cannot be performed without contrast (allergy, toxicity)
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- lack of experience for extra-cranial venous system
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- less contrast resolution than MRV
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Plethysmography[105, 106]
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- noninvasive
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- higher false-positive rate due to venous compression arising from incorrect patient positioning or the action of extrinsic masses
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- provides valuable information regarding the impact of reflux and obstruction on overall venous function
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- low resolution
|
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- can monitor the dynamics of venous disease over time and evaluation of treatment outcomes
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