Ultrasound and Vascular Lab

What is an ultrasound?

Ultrasound has been used as a noninvasive diagnostic medical test to assess soft tissue structures for over 40 years. Ultrasound uses sound waves with sophisticated computers to produce multiple images, or pictures, of the inside of the body.

Ultrasound of a fetus

Ultrasound exams use a transducer that sends high-frequency ultrasonic sound waves to look at the internal soft tissues organs. When the transducer is placed against the skin, the ultrasonic sound waves move through the skin and other body tissues to the organs and structures. The sound waves bounce off the organs like an echo and return the waves back to the transducer. The transducer picks up the reflected waves that are converted by a computer into an electronic picture of the organs or tissues. Different types of body tissues affect the speed at which sound waves travel. Sound travels the fastest through bone tissue and moves slowly through the air. The speed and amount of the sound waves that are returned are translated by the transducer as different types of tissue. No radiation is used in ultrasound so the risks to patients are negligible.

Diagnostic Radiology Vascular Technologists

OHSU Diagnostic Imaging Services highest priority is to provide the best positive patient experience. Please feel free to call with questions regarding your appointment: 503-418-0990.

What should I expect during my visit?

Ultrasound Tech scanning patient

Your appointment is unique to you. If you were not provided with a specific appointment date and time by your provider, please call us to schedule your Ultrasound or Vascular exam. When you call to schedule your appointment, a scheduling professional will provide you with any preparation instructions specific to your exam. You can also obtain preparation instructions via e-mail by signing up for MyChart during your clinic visit. On the day of your US exam, a technologist may ask you to remove clothing or other objects that may interfere with the procedure. If you are asked to remove any clothing, you will be given a gown to wear. A gel-like substance will be applied on the area of the body to undergo the ultrasound (the gel acts as a conductor). A transducer is used by the ultrasound technologist by moving it around in the gel to view various structures on the screen. There are no confirmed adverse biological effects on patients or instrument operators caused by exposures to ultrasound.

What is a Vascular Doppler Ultrasound?

Blood flow can be assessed by using ultrasound. By using Ultrasound and Doppler the velocity and direction of blood flow in the vessel can be evaluated. The velocity (cm/sec) and the audible sound indicates the rate of blood flow within a blood vessel. Absence, faintness and velocity of the signal may indicate an obstruction (blockage) of blood flow. To assess blood flow in the limbs, segmental blood pressures may also be performed.

Male patient neck Ultrasound

Ultrasounds are used to view internal organs in "real time," like a live TV broadcast to assess blood flow through various vessels. Ultrasound procedures are often used to examine many parts of the body such as the abdomen, breasts, female pelvis, scrotum, thyroid and parathyroid glands, and the vascular system. During pregnancy, ultrasounds are performed to evaluate the development of the fetus. Technological advancements in the field of ultrasound now include images that can be made in a three-dimensional view (3-D) and/or four-dimensional (4-D) view. The added dimension of the 4-D is motion so that it is a 3-D view with movement.

OHSU's Ultrasound department is accredited by the American College of Radiology (ACR). OHSU’s Vascular Lab department is accredited by the Intersocietal Accreditation Commission (IAC). This designation is gained by seeking and earning accreditation through the acquisition of clinical images, submission of relevant physician reports corresponding to clinical images submitted, and quality control documentation.1
1American College of Radiology

Leg getting an Ultrasound

Ultrasound and pregnancy

Diagnostic Radiology works closely with departments such as Gynecology and Obstetrics and Perinatology for your Pregnancy Care. A screening ultrasound is sometimes done during the course of a pregnancy to monitor normal fetal growth and verify the due date. Ultrasounds may be performed at various times throughout pregnancy for different reasons:

Pregnant patient getting an Ultrasound

First trimester

•    Confirm or establish the dates of a pregnancy
•    Determine the number of fetuses and identify placental structures
•    Diagnose an ectopic pregnancy or miscarriage
•    Examine the uterus and another pelvic anatomy
•    In some cases to detect fetal abnormalities

Mid-trimester: (sometimes called the 18 to 20 week scan)

•    Confirm pregnancy dates
•    Determine the number of fetuses and examine the placental structures
•    Assist in prenatal tests such as an amniocentesis
•    Examine the fetal anatomy for the presence of normal and/or possible abnormalities
•    Check the amount of amniotic fluid
•    Examine blood flow patterns
•    Observe fetal behavior and activity
•    Examine the placenta
•    Measure the length of the cervix
•    Monitor fetal growth

Third trimester:

•    Monitor fetal growth
•    Check the amount of amniotic fluid
•    Biophysical profile
•    Fetal position 
•    Assess the placenta