A portable cryosurgical device comprising: a portable countertop enclosure housing a cryogen source; a cryogen flow tube connected in fluid communication with the cryogen source; a flow path assembly , wherein the flow path assembly includes: a solenoid valve positioned between the cryogen source and the cryogen flow tube and in fluid communication with the cryogen source and the cryogen flow tube , wherein the solenoid valve includes a valve body with: a valve seat , an inlet port on an inlet side of the valve seat that introduces the cryogen from the cryogen source into the valve body; an outlet port on an outlet side of the valve seat that receives the cryogen from the valve body; a piston movable to cause the valve seat to move from a closed position preventing passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat to an open position permitting the passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat ; characterised in that the valve body from the inlet port to the outlet port includes a dead volume of less than 25 μL. a portable countertop enclosure housing a cryogen source; a cryogen flow tube connected in fluid communication with the cryogen source; a flow path assembly , wherein the flow path assembly includes: a solenoid valve positioned between the cryogen source and the cryogen flow tube and in fluid communication with the cryogen source and the cryogen flow tube , wherein the solenoid valve includes a valve body with: a valve seat , an inlet port on an inlet side of the valve seat that introduces the cryogen from the cryogen source into the valve body; an outlet port on an outlet side of the valve seat that receives the cryogen from the valve body; a piston movable to cause the valve seat to move from a closed position preventing passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat to an open position permitting the passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat ; characterised in that the valve body from the inlet port to the outlet port includes a dead volume of less than 25 μL. a solenoid valve positioned between the cryogen source and the cryogen flow tube and in fluid communication with the cryogen source and the cryogen flow tube , wherein the solenoid valve includes a valve body with: a valve seat , an inlet port on an inlet side of the valve seat that introduces the cryogen from the cryogen source into the valve body; an outlet port on an outlet side of the valve seat that receives the cryogen from the valve body; a piston movable to cause the valve seat to move from a closed position preventing passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat to an open position permitting the passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat ; a valve seat , an inlet port on an inlet side of the valve seat that introduces the cryogen from the cryogen source into the valve body; an outlet port on an outlet side of the valve seat that receives the cryogen from the valve body; a piston movable to cause the valve seat to move from a closed position preventing passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat to an open position permitting the passage of the cryogen from the inlet side of the valve seat to the outlet side of the valve seat ; characterised in that the valve body from the inlet port to the outlet port includes a dead volume of less than 25 μL. <EOS>