Needle guide and method for determining the position of a needle

A needle guide, comprising:

• a coupler;
• a fixed part having a conical shape configured to be fixedly mounted to an imaging probe via the coupler, the fixed part having a hollow conical cavity with an open proximal end and a round distal end defining an opening configured to allow a needle to pass therethrough, wherein the opening in the round distal end is smaller than the open proximal end;
• a movable part configured to be at least partially received within the hollow conical cavity of the fixed part, the movable part defining a second cavity for receiving the needle, wherein the movable part comprises one or more needle guide elements within the movable part, wherein the one or more needle guide elements comprising:
• a fixed needle guide element,
• a resilient needle guide element, and
• a rotatable element;
• at least one rotation sensor configured to measure an anaular rotation of the movable part relative to the fixed part;
• and
• at least one displacement sensor configured to attach to the rotatable element and to measure displacement of the needle relative to the movable part.