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* Ultrasound is used to help diagnose a variety of conditions, such as: * Doppler ultrasound images can help the physician to see and evaluate: * For most ultrasound exams, the patient is positioned lying face-up on an examination table that can be tilted or moved. A clear gel is applied to the area of the body being studied to help the transducer make secure contact with the body and eliminate air pockets between the transducer and the skin. The sonographer (ultrasound technologist) or radiologist then presses the transducer firmly against the skin and sweeps it back and forth over the area of interest. * * * Most ultrasound scanning is noninvasive (no needles or injections) and is usually painless. Ultrasound is widely available, easy-to-use and less expensive than other imaging methods. Ultrasound imaging uses no ionizing radiation. Ultrasound scanning gives a clear picture of soft tissues that do not show up well on x-ray images. Ultrasound causes no health problems and may be repeated as often as is necessary. Ultrasound provides real-time imaging, making it a good tool for guiding minimally invasive procedures such as cortisone injections, needle biopsies and needle aspiration of fluid in joints or elsewhere. * Ultrasound does not penetrate air or bone. So if an abnormality is behind bowel gas, ribs, or calcified rib cartilage, it may not be discovered. · Because ultrasound is absorbed and reflected inside the body, only some of the waves reach deep places farthest from the transducer. Theres a limitation to ultrasounds ability to look deep into the body. Of two tumors of equal size, the tumor closest to the transducer will be discovered more readily than the more distant one. Examinations, consequently, are not as productive for obese, tall patients as they are for thin or petite ones. · Ultrasonography is an operator-dependent, subjective test. The more experience the operator has, the better the patient listens to his instructions (hold your breath