Medical Imaging System

Presentation on theme: "Medical Imaging System"— Presentation transcript:

1 Medical Imaging System
Unit-III: Medical Imaging System: Lectures required Topic Books L17-L18 L19-L20 L21-L22 Medical Imaging System Instrumentation for diagnostics X-rays, basic properties of X-rays, X-ray machines, Special imaging techniques. Ultrasonic imaging systems physics of ultrasound, biological effect of ultrasound, Ultrasonic A Scan, B Scan, M Scan, real-time ultrasonic imaging system T2, T1 VM Umale Dept. of Electronics and Telecommunication Engineering

2 Dept. of Electronics and Telecommunication Engineering
classification: Classification of basic modes of transmission Ultrasound waves can be transmitted in various forms Pulsed ultrasound Continuous doppler Pulsed doppler Range gated pulsed doppler Classification of Ultrasonic imaging system The images of the internal structure of the body can be obtained with following scanning techniques or scan modes A -scan display M-scan display B-scan display Real time mode vm umale Dept. of Electronics and Telecommunication Engineering

3 Dept. of Electronics and Telecommunication Engineering
classification: Pulsed ultrasound – Continuous doppler- Pulsed doppler- Range gated pulsed doppler- vm umale Dept. of Electronics and Telecommunication Engineering

4 Pulsed –echo ultrasound setup Block diagram
Pulse repetition freq. Generator Transmitter Transducer Time delay Saw tooth Generator Swept Gain Wide Band Amplifier Time Marker Detector Video Amplifier CRO Gain Control vm umale Dept. of Electronics and Telecommunication Engineering

5 Unit-III: Medical Imaging System:
Ultrasonic probes VM Umale Dept. of Electronics and Telecommunication Engineering

6 Ultrasonic imaging system
Imaging can provide valuable information such as size, location , displacement/velocity of a given internal organs or structures. No need of surgery No potentially harmful radiation Non-invasive imaging Non-traumatic imaging Tumors, cysts, etc having different densities than body organ tissues therefore easy to detect by ultrasonic imaging techniques The images of the internal structure of the body can be obtained with various ultrasonic imaging( Scanning) techniques or Scan modes vm umale Dept. of Electronics and Telecommunication Engineering

7 Dept. of Electronics and Telecommunication Engineering
classification: Ultrasonic imaging system The images of the internal structure of the body can be obtained with following Scanning techniques or Scan modes: A -scan display M-scan display B-scan display Real time mode vm umale Dept. of Electronics and Telecommunication Engineering

8 1D, 1dimensional information
Ultrasonic imaging system A Scan: 1D, 1dimensional information Echoes are displayed as vertical blips as the beam is swept across the CRT The height of the vertical blips is the strength of the echo The position from L to R across CRT face gives the depth of the tissue from the transducer. VM Umale Dept. of Electronics and Telecommunication Engineering

9 For A Scan Application (requirement) CRT-
Ultrasonic imaging system For A Scan Application (requirement) CRT- Electrostatic defection type with post defection acceleration of electron beam. It helps to get bright trace with low defecting voltage Flat face CRT integrated with storage facility Application of A-scan mode 1. Echoencephaloscope / Echoencephalography 2. Echophthalmoscope VM Umale Dept. of Electronics and Telecommunication Engineering

10 Application of A-scan mode 1. Echoencephaloscope / Echoencephalography
Ultrasonic imaging system Application of A-scan mode 1. Echoencephaloscope / Echoencephalography The Midline surface of the brain Head injury -Tilting of brain due to bleeding ,shift in position of vertical blips -Tumors grows in the brain, anatomy of brain is altered The instrument for diagnosis & detection of the mid line of the brain is called “Echoencephaloscope” - Measuring range – 0-18 cm of tissue depth - Frequency range – 1-3MHz - Probe diameter – 15-20mm ( for 2Mhz) For elderly patient select f= 1MHz, Echoes received frame the brain. VM Umale Dept. of Electronics and Telecommunication Engineering

11 Ultrasonic imaging system
Scan-A mode: e.g. Echoencephalogram Echoes received from the brain In the normal brain, the mid line echoes coincide for each way In the abnormal case, there is a shift between the two echoes VM Umale Dept. of Electronics and Telecommunication Engineering

12 Ultrasonic imaging system
Scan-A VM Umale Dept. of Electronics and Telecommunication Engineering

13 Application of A-scan mode 2. Echo-ophthalmoscope
Ultrasonic imaging system Application of A-scan mode 2. Echo-ophthalmoscope A Scan * Usefule in ophthalmoscopy for the dignosis Retinal dislocation, Intra ocular tumours, Vitreous opacities orbital tumour, Lens dislocation. If helps in the measurement of axial length in patient with progressive myopia, localization of intra ocular foreign bodies extraction of non magnetic foreign bodies. VM Umale Dept. of Electronics and Telecommunication Engineering

14 Application of A-scan mode 2. Echo-ophthalmoscope
Ultrasonic imaging system Application of A-scan mode 2. Echo-ophthalmoscope - It employs MHz pencil type transducer Echoes obtained when performing an anterior- posterior examination along the optical axis ( ref surface of the lid, surface of the cornea. the anterior lens capsules, the posterior lens capsule, The posterior wall of the globe (retina echo at, choroid & sclera), refrobulbar fat.) Thickness of lens 3 mm Gross axial length-24mm & depth of anterior chamber = 3mm VM Umale Dept. of Electronics and Telecommunication Engineering

15 Ultrasonic imaging system
Scan-A mode: e.g. Echopohthalmoscope Acoustics landmarks in the normal eye along the optical axis. The electronic markers shown on the figure represents 2mm of actual tissue depth VM Umale Dept. of Electronics and Telecommunication Engineering

16 Ultrasonic imaging system
Typical M-mode display from various structures of the heart with different directions of the probe VM Umale Dept. of Electronics and Telecommunication Engineering

17 Ultrasonic imaging system
Block diagram of an echocardiograph circuit VM Umale Dept. of Electronics and Telecommunication Engineering

18 Ultrasonic imaging system
Difference between Scan-A, B and M Principle of time-motion (M-Mode) display VM Umale Dept. of Electronics and Telecommunication Engineering

19 Ultrasonic imaging system
Difference between A-scan and B-scan displays VM Umale Dept. of Electronics and Telecommunication Engineering

20 Ultrasonic imaging system
Scan-B VM Umale Dept. of Electronics and Telecommunication Engineering

21 Ultrasonic imaging system
Types of Scanning arrangement: Three Types of Scanning arrangement Linear scan Sector scan Compound scan VM Umale Dept. of Electronics and Telecommunication Engineering

22 Ultrasonic imaging system
Real time Image System Different arrangements in multi-element array scanners Linear sequential array Curve –linear array Linear phased array Phased array VM Umale Dept. of Electronics and Telecommunication Engineering

23 Ultrasonic imaging system
Real time Image System VM Umale Dept. of Electronics and Telecommunication Engineering

24 A : Thanks a lot VM Umale Dept. of Electronics and Telecommunication Engineering

25 xxxxx Echophthalmoscope Ultrasonic imaging system :
VM Umale Dept. of Electronics and Telecommunication Engineering