Popliteal cyst aspiration under ultrasound guidance

MRI in the axial plane through the knee (A) using a fat-suppressed proton density sequence shows a septated popliteal cyst (arrow). Image B is an ultrasound and shows an anechoic septated cyst. Image C shows a needle tip (arrowhead) in the decompressed cyst (arrow). Eight ccs of thick gelatinous fluid were aspirated.