Biceps tendon can be examined both with MRI of the shoulder or Ultrasound of the shoulder.
The findings on ultrasound indicating tendinopathy are the same as with other tendons:
fluid in the tendon sheath (note: it communicates with the shoulder joint and is therefore no...
There are several approaches to ultrasound examination of the adult hip.
supine with the hip in mild external rotation
sagittal oblique plane parallel to the long axis of the femoral neck to assess femoral head and neck and for any joint effusio...
Ultrasound appearance of liver metastases can have bewildering variation.
Patterns do exist between ultrasound appearance of the liver metastases and the likely primary, which is sometimes helpful in directing a search for an unknown primary, as well as helping distinguish between benign lesion...
A pseudodysraphism refers to the splayed appearance of a normal spine created due to excessive craniocaudal angulation during sonographic evaluation. This can erroneously lead to the diagnosis of a spinal neural tube defect.
Medical ultrasound is based on the use of high-frequency sound to aid in the diagnosis and treatment of patients. Ultrasound frequencies range from 2 to approximately 15 MHz, although even higher frequencies may be used in some situations.
The ultrasound beam originates from mechanical oscillat...
Ultrasound frequencies in diagnostic radiology range from 2 MHz to approximately 15 MHz.
It is important to remember that higher frequencies of ultrasound have shorter wavelengths and are absorbed/attenuated more easily. Therefore, higher frequencies are not as penetrating. This explains why h...
Piezoelectric effect refers to applying an electric field to a crystal, which causes realignment of the internal dipole structure resulting in the crystal to lengthen or contract. The process converts electrical energy into kinetic or mechanical energy.
The reverse of the piezoelectric effect c...
The first written document dealing with the use of waves in spatial orientation dates back to 1794, when Lazaro Spallanzani (“Opus coli di fisica”), analyzed the basic mechanisms of spatial orientation of the bats, proposing other mechanisms of spatial orientation than the visual – ophthalmic sy...
Ultrasound evaluation of breast cysts is the modality of choice. Obstruction of the ducts, often appearing as the result of epithelial hyperplastic processes or the stromal fibrosis, or both processes lead to the formation of cysts, disabling the drainage of the terminal ducts of the lobules.
A number of sonographic features are helpful in distinguishing reactive versus malignant lymph nodes.
Grey scale features
Features that favour reactive/infective nodes over malignancy include:
surrounding soft tissue oedema
Doppler examination is particularly...
Ultrasound assessment of carotid arterial atherosclerotic disease has become the first choice for carotid artery stenosis screening, permitting the evaluation of both the macroscopic appearance of plaques as well as flow characteristics in the carotid artery.
This article focus on internal caro...
The resisitive index (RI) is the commonest Doppler parameter used for hepatic arterial evaluation. The usual range in normal as well as post transplant individuals is between 0.55 and 0.8.
It is measured by:
RI = (peak systolic velocity - end diastolic velocity)/peak systolic velocity
The colour comet-tail artifact is an ultrasonographic sign seen in a number of situations when colour Doppler scanning is performed.
Typically the artifact, which resembles the grey-scale comet-tail artifact, is seen in a situation when a small highly refractive (usually calcific) object is int...
The comet-tail artifact is a grey-scale ultrasound finding seen when small calcific / crystalline / highly reflective objects are interrogated and is believed to be a special form of reverberation artifact.
It is similar to the colour comet-tail artifact and is seen in similar situations, altho...
Causes of generalised reduction of liver echogenicity on ultrasound include:
diffuse malignant infiltration
generalised increase in liver echogenicity
hepatic attenuation on CT
Causes of generalised increased liver echogenicity includes:
diffuse fatty infiltration
cirrhosis: can be coarsened as well
chronic hepatitis 3: can be coarsened as well
diffuse infiltration or deposition
The keyhole sign is an ultrasonographic sign seen in boys with posterior urethral valves. It refers to the appearance of the proximal urethra (which is dilated) and associated thick walled distended bladder which on ultrasound may resemble a key hole.