DEVELOPMENT A-MODE ULTRASONOGRAPHY PROTOTIPE FOR THE CHARACTERIZATION OF SPINAL NEEDLE ACOUSTIC SCATTERING PATTERN

• Main Author: Ababil, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/41459
• Institution: Institut Teknologi Bandung

B-mode, which in principle is a combination of several amplitude echo A-modes in each element transducer. The crucial problem in needle imaging using B-mode USG is inconsistent visibility. The needle visibility in B-mode is related to A-mode acoustic scattering pattern which is the result of ultrasonic wave and needle interaction received by each transducer element. The evaluation of acoustic scattering pattern in A-mode which focus in the interaction of ultrasonic wave, needle and several factors such as puncture angle, needle size and wave frequency needs to be studied further. In this research, an A-mode USG prototipe for spinal needle acoustic scattering pattern characterization will be designed. Designed prototipe USG consists of pulser, immersion transducer and digital osiloscope. Acoustic scattering pattern testing is carried out in testing system consists of testing medium and needle positioning robot. The testing medium is arranged to obtain the homogen and anechoic condition. Therefore, the acoustic scattering pattern of spinal needle can be isolated. The needle positioning robot is used to obtain high testing accuracy. Acoustic scattering pattern testing is carried out by changes the puncture angle between 0o and 45o with 5o resolution and the size of needle from 18G, 20G and 22G. The result of acoustic scattering pattern examination is processed in time domain and frequency domain. The acoustic scattering pattern in time domain and frequency domain is not linear against variance of needle puncture angle and needle dimension. In time domain, amplitude of acoustic scattering pattern have a high value on 0o then fall on 5o. Then the amplitude of acoustic scattering pattern rise again until 45o. In frequency domain, the value of energy spectral density (ESD) is high on 0o and fall on 5o. But, the ESD value rise again until 40o on 18G needle and 30o on 20G and 22G needle. Then the ESD value fall again until 45o. This result show that the interaction between ultrasonic wave and spinal needle will generate a unique acoustic scattering pattern.