Hydatid disease, caused by Echinococcus granulosus, is a parasitic disease that is endemic in many parts of the world. Hydatid cyst demonstrates a variety of imaging features, varying according to growth stage, associated complications, and affected tissue. The radiologic findings range from purely cystic lesions to a completely solid appearance. Ultrasound is the most important imaging modality for liver hydatid disease and clearly demonstrates the floating membranes, daughter cysts, and hydatid sand characteristically seen in purely cystic lesions. The radiologist's familiarity with the imaging findings of the disease is very important for earlier diagnosis and an appropriate treatment.
Its informative about the medical imaging in Nepal and the general news, Radiography articles and related ones.
Monday, June 15, 2015
Hepatic hydatid
Hydatid disease, caused by Echinococcus granulosus, is a parasitic disease that is endemic in many parts of the world. Hydatid cyst demonstrates a variety of imaging features, varying according to growth stage, associated complications, and affected tissue. The radiologic findings range from purely cystic lesions to a completely solid appearance. Ultrasound is the most important imaging modality for liver hydatid disease and clearly demonstrates the floating membranes, daughter cysts, and hydatid sand characteristically seen in purely cystic lesions. The radiologist's familiarity with the imaging findings of the disease is very important for earlier diagnosis and an appropriate treatment.
Friday, June 5, 2015
Sunday, April 5, 2015
Acute cholecystitis !
Ultrasound (US) is the preferred initial modality in the investigation of right upper quadrant pain. It is more sensitive than HIDA scintigraphy and CT in the diagnosis of acute cholecystitis, and more readily available.
The most sensitive US finding in acute cholecystitis is the presence of cholelithiasis in combination with the sonographic Murphy sign. Both gallbladder wall thickening (>3 mm) and pericholecystic fluid are secondary findings.
Other less specific findings include gallbladder distension and sludge.
Every effort should be made to demonstrate the obstructing stone in the gallbladder neck or cystic duct.
Sunday, March 29, 2015
US vs CT
US vs CT
Multi-slice CT is increasingly replacing ultrasonography (US) for the evaluation of patients with acute abdominal pain
CT has major advantages over US: it is extremely fast and its time burden is often less than that of a US examination .
CT is not disturbed by gas and bone, while obesity is even an advantage.
Most of all, CT is not operator-dependent and can be reviewed by others, even at a distance.
With all these advantages, it is not surprising that US is losing field in the evaluation of the acute abdomen.
US however has some advantages.
advantages of US:
- US does not require ionizing radiation, which can be important in younger patients and pregnant women.
- The spatial resolution of a high-frequency US image is higher than that of a CT image.
This is only true if the target organ can be approached closely, which requires either a thin patient or the use of graded compression.
What is Ultrasound?
What is Ultrasound?
Sound is a physical phenomenon that transfers energy from one point to another. In this respect, it is similar to radiation. It differs from radiation, however, in that sound can pass only through matter and not through a vacuum as radiation can. This is because sound waves are actually vibrations passing through a material. If there is no material, nothing can vibrate and sound cannot exist.
One of the most significant characteristics of sound is its frequency, which is the rate at which the sound source and the material vibrate. The basic unit for specifying frequency is the hertz, which is one vibration, or cycle, per second. Pitch is a term commonly used as a synonym for frequency of sound.
The human ear cannot hear or respond to all sound frequencies. The range of frequencies that can be heard by a normal young adult is from approximately 20 Hz to 20,000 Hz (20 kHz). Ultrasound has a frequency above this range. Frequencies in the range of 2 MHz (million cycles per second) to 20 MHz are used in diagnostic ultrasound. Ultrasound is used as a diagnostic tool because it can be focused into small, well-defined beams that can probe the human body and interact with the tissue structures to form images.
What is Transducer?
The transducer is the component of the ultrasound imaging equipment that is placed in direct contact with the patient's body. It performs several functions as will be described in detail later. It's first function is to produce the ultrasound pulses when electrical pulses are applied to it. A short time later, when echo pulses return to the body surface they are picked up by the transducer and converted back into electrical pulses that are then processed by the system and formed into an image.
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