- Duplex ultrasonography
Duplex ultrasonography Diagnostics MeSH D018616
Duplex ultrasonography (more commonly but less correctly known as duplex ultrasound) is a form of medical ultrasonography that incorporates two elements:
- 1) Grayscale Ultrasound to visualize the structure or architecture of the body part. No motion or bloodflow is assessed. This is the way plaque is directly imaged in a blood vessel, with the reader typically commenting on crossectional narrowing (greater than 70% is typically considered worthy of treatment).
- 2) Color-doppler Ultrasound to visualize the flow or movement of a structure, typically used to image blood within an artery. We see blood flow velocities increase through a region of narrowing, like a finger pressing up against the end of a running garden hose. Increased velocities indicate a region of narrowing or resistance (velocities greater than 250 cm/sec typically considered worthy of treatment).
Both displays are presented on the same screen ("duplex") to facilitate interpretation.
Vascular ultrasonography is the main branch of radiology that uses duplex. Vascular ultrasonography, a subspeciality within ultrasonography, helps determine multiple factors within the circulatory system. It can evaluate central (abdominal) and peripheral arteries and veins; it helps determine the amount of vascular stenosis (narrowing) or occlusion (complete blockage) within an artery; it assists in ruling out aneurysmal disease; and it is the main aid to rule out thrombotic events. Duplex is an inexpensive, non-invasive way to determine pathology. Duplex evaluation is usually done prior to any invasive testing or surgical procedure. Ultrasound duplex scanning can provide additional information that may guide therapeutic decisions. The location and severity of arterial narrowings and occlusions can be identified. The vascular technologist can map disease in lower-extremity segments with great accuracy — though duplex scanning is more time-consuming than other lower-extremity arterial studies.
Health science – Medicine · Surgery · Vascular surgery and other vascular procedures (ICD-9-CM V3 38-39, ICD-10-PCS 03-6) Incision, excision,
Peripheral arterial occlusive disease: Balloon embolectomy · Thrombectomy
Carotid stenosis: Endarterectomy (Carotid endarterectomy)
Varicose veins: Ambulatory phlebectomy · Laser ablation · Sclerotherapy · Vein stripping
Temporal artery biopsyArteriotomy · Phlebotomy
Peripheral arterial occlusive disease: Peripheral arterial bypass surgery
Portal hypertension: Transjugular intrahepatic portosystemic shunt (TIPS) · Distal splenorenal shunt procedure
Vascular grafting (Human umbilical vein graft)Blalock–Taussig shuntRepair
Aortic aneurysm / dissection: Open AAA repair · Endoluminal AAA repair (EVAR)
Peripheral arterial occlusive disease: Angioplasty with/out StentingAtherectomyAuxiliary to
Angiography (Digital subtraction angiography, Cerebral angiography, Aortography, Fluorescein angiography, Radionuclide angiography, Magnetic resonance angiography)
Venography (Portography) · Impedance phlebographyIntravascular ultrasound · Carotid ultrasonography
Other diagnosticAngioscopy · Ankle brachial pressure index · Tilt table testCategories:
- Medical ultrasound
- Medicine stubs
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