摘要 |
<p>A cryogen supply unit is disclosed for controlling the flow of a Joule-Thompson fluid through a cryosurgical instrument. The supply unit includes a fluid flow path manifold block (16) formed as an assembly of three sub-units (16a, 16b, 16c). The manifold block includes internal fluid passageways and carries functional devices including pressure regulators (36, 82), open/closed valves (54, 56, 90, 92), connector sockets (30, 22, 86) and fluid pressure sensors (40, 46). The manifold avoids the need for conventional floating or suspended tubes to link the functional devices. A defrosting method is also described for defrosting the Joule-Thompson instrument by applying generally equal pressures of cryogen fluid to the inlet and exhaust channels of the instrument.</p> |