Sampled Aperture Techniques Applied to B-Mode Echoencephalography

摘要: Whereas A-mode echoencephalography has been found diagnostically useful, B-mode displays for similar object volumes have not yet provided the additional information that might be expected from a two-dimensional presentation. Poor image quality results number of causes stemming presence skull bone (White, 1967; 1968). Large differences in specific acoustic impedance between and soft tissue combined with irregularities surfaces result unfavorable reflections reverberations energy. Severe attenuation ultrasound at useful frequencies further reduces system sensitivity target acquisition. Additionally, significant velocities beam degradation registration errors image. With one possible exception (Somer, 1969), nature extent these aberrations thus far limited practical utilization scanners clinical examinations head structure.