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