Breast ultrasound
Breast ultrasound is the use of medical ultrasonography to perform imaging of the breast. It can be considered either a diagnostic or a screening procedure. It may be used either with or without a mammogram. It may be useful in younger women, where the denser fibrous tissue of the breast may make mammograms more difficult to interpret. Automated whole-breast ultrasound (AWBU) is an ultrasound investigation of the breast that is largely independent of the operator skill and that allows the reconstruction of volumetric images of the breast. Using high-frequency ultrasound, a diagnostic evaluation of the lactiferous  ducts by means of ultrasound (duct sonography) can be performed. In this manner, dilated ducts and intraductal masses can be made visible. Another technique for visualizing the system of lactiferous ducts is galactography, which allows a wider area of the lactiferous duct system to be visualized. A type of ultrasound examination to measure tissue stiffness, which is used to detect tumours, is elastography. Breast ultrasound is also used to perform fine-needle aspiration biopsy and ultrasound-guided fine-needle aspiration of breast abscesses. Some women prefer breast ultrasound over mammography because they dislike the pain felt during squeezing or fixing  of breast done during mammography for X-ray views. Breast ultrasound is painless procedure. Breast ultrasound is usually done with frequency 7 Megahertz to 14 Megahertz. Breast ultrasound includes ultrasound of axillary tail of breast and sometime it includes ultrasound of axillae also to detect abnormal nodes in axilla because lymphatic drainage of parts of breast occur through axillary lymph nodes.