ultrasound
TRANSCRIPT
N U R A I N A B I N T I A B KA D I R
ULTRASOUND AND MEDICAL APPLICATIONS
CONTENTS
• Introduction• Components • Appearances of different organs in imaging• Uses • Advantages and disadvantages• Breast ultrasound
INTRODUCTION
• Ultrasounds are the sound waves with a frequency of greater than 20000 cycles per second(20KHz)• Diagnostic : 2-10 MHz• Pulse echo principle
Ultrasound probe
pulses of high frequency
Transmitted-patient
Echo returning
Processed information by
computer
Visualize on screen
COMPONENTS
PIEZO-ELECTRIC EFFECT
• Piezo-electric crystal• Electric energyultrasonic energytissue(vice
versa)• Common in medical ultrasound: Lead Zirconate
Titanate(PZT)
COMMONLY USED TRANSDUCER FREQUENCY
Low frequency 3-5 MHz
• Adult abdomen scanning• Renal • Gall bladder• Aorta for echocardiography• Transabdominal gynecologal scanning
High frequency
5,7.5,10 MHz
• Pediatric abdomen• Vascular • Scrotal scanning• Transvaginal scans
APPEARANCE OF DIFFERENT ORGANS ON ULTRASOUND IMAGING
• Organ reflects the ultrasound beam completely bright with posterior acoustic shadowing eg: renal calculus
APPEARANCE OF DIFFERENT ORGANS ON ULTRASOUND IMAGING
• Structure transmits the sound waves fully anechoic(black) on ultrasound imaging with posterior acoustic enhancement • eg: simple cyst of kidney
APPEARANCE OF DIFFERENT ORGANS ON ULTRASOUND IMAGING
• Structure transmits and reflects ultrasound waves partiallygrey on ultrasound imaging• Eg: tumour
USES
• Non invasive and safe mode of antenatal assessment of the fetus
• Non invasive screening modality for diagnosing abdominal pathologies like liver, spleen, gallbladder, biliary tree, mesentry, omentum and peritoneum
• Assess renal and retro-peitoneal compartments• Evaluate soft tissues, bones and joints• Doppler evaluation of blood vessels• Infants with open fontanellae intracranial pathologies• Breast,thyroid
ADVANTAGES
• Noninvasive (no needles or injections) painless.• Widely available • Less expensive• Does not use any ionizing radiation.• Gives a clear picture of soft tissues that do not
show up well on x-ray images.• Preferred imaging modality for the diagnosis and
monitoring of pregnant women and their unborn babies.• Real-time imaging, making it a good tool for
guiding minimally invasive procedures such as needle biopsies and needle aspiration.
DRAWBACK OF ULTRASONOGRAPHY
• Ultrasound beam is not very useful for the evaluation of the:• Small and large bowel• Bone and marrow pathologies• Bowel gas may obscure the window for kidney,
retroperitoneum, aorta and para aortic areas.
BREAST ULTRASOUND
INTRODUCTION
• To evaluate breast abnormalities found in:• Screening or diagnostic mammography• During a physician performed clinical breast
examination• Ultrasound guided breast biopsy
• Benefits• Noninvasive• Less expensive• Extremely safe• Gives a clear picture
of soft tissues• Real-time imaging
(biopsies/aspiration)• Detect lesions in
dense breasts
• Limitations
• Many calcifications cannot be seen on ultrasound but seen on mammography
ULTRASOUND GUIDED BREAST BIOPSY
• Breast biopsies are usually done on an outpatient basis.• A local anesthetic will be injected into the breast
to numb it.• Pressing the transducer to the breast, the
sonographer or radiologist will locate the lesion.
REFERENCES
• Concise radiology for Undergraduates,Bhushan N.Lakhar,page 1-3• http://
www.radiologyinfo.org/en/info.cfm?pg=breastbius• http://
www.imaginis.com/ultrasound/ultrasound-imaging-of-the-breasts-2