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What is an Ultrasound Scan?
An ultrasound scan, also known as sonography, is a highly safe, painless, and non-invasive diagnostic imaging technique. It uses high-frequency sound waves to penetrate the skin and bounce off internal organs and tissues. The echoes produced are then captured by a transducer and instantly converted by a computer into real-time, moving images of the inside of your body.
Unlike X-rays or CT scans, ultrasound involves absolutely no ionizing radiation. This makes it an incredibly safe first-line diagnostic tool for patients of all ages, including pregnant women and children. It provides doctors with a clear view of soft tissues, internal organs, and blood flow, ensuring an accurate diagnosis.
Clinical Applications & Scope of Examination:
- Upper Abdomen: Detailed assessment of the liver, gallbladder, spleen, pancreas, and kidneys. It is highly effective in diagnosing fatty liver, cirrhosis, gallstones, kidney stones, and various cysts or tumors.
- Lower Abdomen & Pelvis:
- Female: Examines the uterus and ovaries to detect fibroids, ovarian cysts, or polycystic ovary syndrome (PCOS).
- Male: Evaluates the prostate and bladder to check for prostate enlargement or tumors.
- Breasts: Helps distinguish between fluid-filled cysts and solid masses in the breast. It is a standard screening tool for younger women and a crucial supplement to mammography.
- Thyroid & Neck: Detects enlarged thyroid glands (goiter), nodules, cysts, and evaluates any abnormal lymph nodes in the neck.
- Vascular (Doppler Ultrasound): Assesses blood flow speed and direction in blood vessels (e.g., carotid arteries, leg veins) to diagnose deep vein thrombosis (DVT) or vascular blockages.
Specific Preparations Based on the Exam Area:
- Upper Abdomen (Liver, Gallbladder, Pancreas, etc.): You must fast for 6 to 8 hours prior to the scan. Please avoid smoking or chewing gum to minimize bowel gas, which can obscure images. Fasting also ensures your gallbladder is fully distended with bile for a clearer view. (Small sips of water are allowed).
- Pelvis & Lower Abdomen (Uterus, Ovaries, Prostate, Bladder): You need to have a full bladder. Please drink plenty of water before your appointment and do not urinate until the scan is complete. A full bladder pushes the intestines out of the way and acts as an “acoustic window” to clearly view the pelvic organs behind it.
- Breast, Thyroid, Neck, or Vascular Ultrasound: Generally, no special preparation or fasting is required.
Is an ultrasound scan safe? Does it use radiation?
Yes, ultrasound is an exceptionally safe medical procedure. It uses high-frequency sound waves rather than ionizing radiation (like X-rays). Therefore, there is zero radiation risk, making it completely safe even for pregnant women, fetuses, and infants.
Is the procedure painful?
Not at all. It is a painless, non-invasive exam. You will only feel the slight pressure of the transducer gliding over your skin and the coolness of the water-based gel. The gel is harmless to your skin and can be easily wiped off with a tissue afterward.
Why do I need to fast for an upper abdominal scan but hold my urine for a pelvic scan?
Fasting reduces gas in your stomach and bowels, which blocks sound waves, and allows your gallbladder to fill with bile, making gallstones easier to spot. Holding your urine fills the bladder, which pushes the gas-filled intestines away and provides a clear “window” for the sound waves to reach the uterus, ovaries, or prostate located behind the bladder.
Can women undergo a pelvic ultrasound during their menstrual period?
Generally, menstruation does not affect a standard transabdominal (external) pelvic ultrasound. However, if a “transvaginal ultrasound” is required, it is usually recommended to wait until your period has completely finished for comfort and hygiene reasons. Please consult our staff during booking if you have concerns.
