What is breast ultrasound?

The ultrasound of breast is the study of internal structure of breast by using high frequency sound waves.

Applications of breast ultrasound:

1. Ultrasound can possibly detect malignancy combined with mammographically detected clustered microcalcifications. It can be possible by using the latest high-frequency transducers.
2. These lesions may be seen as irregular mass, dilated abnormal ducts or clustered foci of increased echogenicity with higher doppler vascularity.
3. Ultrasound is also done as the follow up of mammogram or magnetic resonance imaging (MRI) breast particularly in case of cancer.
4. Ultrasound of breast is used for the combined study of mammography of breast to evaluate the other findings that are not imaged on the mammography.
5. Mammography uses x-rays to give the image of breast tissues so it cannot perform to the females who are pregnant, breast feeding or below the age of 40.

Technique:

With using modern ultrasound equipment high quality images of normal and abnormal breast tissues are produced.

Equipment used:

A 7.5 MHz linear array transducer/probe should be used.

Ultrasound breast anatomy

By using adequate sonographic equipment, we can easily get detailed images all macroscopic breast structure and breast tissues.

The ultrasonic breast anatomy contains following:

• Skin
• Subcutaneous fat
• Cooper’s ligaments
• Breast parenchyma
• Retromammary fat
• Pectoralis muscles
• Ribs: Ribs can be easily identified because bone attenuates causing an acoustic shadow.
• Pleura
• Nipple: A nipple consist of both connective tissue and dense connective tissue of the duct which can create posterior shadowing.
• Ducts: Tubular branching structures

The breast can be divided into four regions:

• Skin, nipple and subareolar tissue
• Subcutaneous region
• Parenchymal region (it is the region between subcutaneous region and retromammary region)
• Retromammary region

Lymph nodes in breast:

A lymph node is defined as the small clumps or bunch of immune cells that acts as filters for your lymphatic system. The lymphatic system carries fluids and cells that runs throughout the body such as blood in circulatory system.

The lymph nodes start to reach in the axillary area (underarm) if the breast cancer is start to spread. These lymph nodes are called as axillary lymph nodes.

Nature of the lymph nodes:

The nature of the lymph nodes is highly related to the prognosis (chances of survival)

Negative lymph nodes: These are the lymph nodes that do not contain cancer.

Positive lymph nodes: These are the axillary lymph nodes that do contain cancer.

Single nodule: Lymph nodes can be enlarged, this condition is termed as lymphadenopathy, these enlarged lymph nodes can be seen as a nodule under the skin and in an ultrasound or another imaging tests.

Echogenic fatty hilum: Normal lymph nodes is ovoid in shape and hypoechoic to the adjacent muscles and frequently contain the echogenic fatty hilum.

Hilum: The hilum is a linear, echogenic, non-shadowing structure and it contains the nodal vessels which appears continuous with the fat around the node.

Fatty hilum: The fatty hilum is the important component of normal lymph node. The fatty hilum can easily combine into the normal fatty tissue of breast.