A medical probe comprising: an external sheath; a rotatable fluid conduit housed within said external sheath, said rotatable fluid conduit including an inner lumen; and a fluid rotary joint comprising: an outer housing including an external port, wherein said external sheath is connected to said outer housing; a rotatable insert having an inner channel, wherein said rotatable insert is rotatable within said outer housing, and wherein a proximal portion of said rotatable fluid conduit is directly connected, or indirectly connected via a torque cable or rotatable shaft, to said rotatable insert, such that said inner channel is in fluid communication with said inner lumen, and such that said rotatable fluid conduit rotates in unison with said rotatable insert; and at least one seal between said rotatable insert and an inner surface of said outer housing; said external sheath defining an outer lumen, wherein said inner lumen is in fluid communication with said outer lumen at a location remote from said proximal portion of said rotatable fluid conduit, wherein said inner channel is configured to be in fluid communication with said external port under rotation of said rotatable fluid conduit; and wherein said rotatable insert is connectable to a rotational drive mechanism; characterized in that said medical probe further comprises a secondary port in fluid communication with said outer lumen, wherein said outer lumen and said inner lumen form a closed internal fluid path connecting said external port with said secondary port, and wherein said secondary port is located such that a direction of fluid flow in the outer lumen is opposite to a direction fluid flow in the inner lumen. an external sheath; a rotatable fluid conduit housed within said external sheath, said rotatable fluid conduit including an inner lumen; and a fluid rotary joint comprising: an outer housing including an external port, wherein said external sheath is connected to said outer housing; a rotatable insert having an inner channel, wherein said rotatable insert is rotatable within said outer housing, and wherein a proximal portion of said rotatable fluid conduit is directly connected, or indirectly connected via a torque cable or rotatable shaft, to said rotatable insert, such that said inner channel is in fluid communication with said inner lumen, and such that said rotatable fluid conduit rotates in unison with said rotatable insert; and at least one seal between said rotatable insert and an inner surface of said outer housing; an outer housing including an external port, wherein said external sheath is connected to said outer housing; a rotatable insert having an inner channel, wherein said rotatable insert is rotatable within said outer housing, and wherein a proximal portion of said rotatable fluid conduit is directly connected, or indirectly connected via a torque cable or rotatable shaft, to said rotatable insert, such that said inner channel is in fluid communication with said inner lumen, and such that said rotatable fluid conduit rotates in unison with said rotatable insert; and at least one seal between said rotatable insert and an inner surface of said outer housing; said external sheath defining an outer lumen, wherein said inner lumen is in fluid communication with said outer lumen at a location remote from said proximal portion of said rotatable fluid conduit, wherein said inner channel is configured to be in fluid communication with said external port under rotation of said rotatable fluid conduit; and wherein said rotatable insert is connectable to a rotational drive mechanism; characterized in that said medical probe further comprises a secondary port in fluid communication with said outer lumen, wherein said outer lumen and said inner lumen form a closed internal fluid path connecting said external port with said secondary port, and wherein said secondary port is located such that a direction of fluid flow in the outer lumen is opposite to a direction fluid flow in the inner lumen.