Distal Acoustic shadow is seen in?
All of the above REF: Ultrasound Teaching Manual by Matthias Hofer page - 15 In simple terms when sound waves strike an interface which reflects it back, it shows on USG as a hypoechoic or anechoic shadow beyond the structure. It is seen with gas and at interface like bone, calculi and stones.
Air
Calculi
Bone
All of the above
All of the above