Apparatus with weeping tip and method of use

A device for delivering a medical substance to a patient comprising:

• a needle having a proximal end, a distal end and a single internal lumen disposed therebetween;
• said distal end having a porous region disposed thereon;
• said porous region including a plurality of pores sized and distributed along at least a radial wall of said porous region;
• and,
• said distal end being at least partially closed such that said medical substance is caused to weep and ooze from said distal end of said needle when pressure is introduced into said device;
• a partial plug permanently disposed at a hole at an end of said distal portion so as to prevent flow out of said hole from substantially exceeding a flow through said plurality of pores;
• and,
• said distal portion having a substantially constant diameter along its length.

A method of delivering a medical substance to a patient comprising:

• providing a needle device having a proximal end and a porous distal end and a single lumen extending therebetween, wherein said porous distal end comprises a plurality of microholes distributed substantially uniformally along said porous distal end;
• introducing said needle device into said patient and guiding said distal end to an injection site in said patient;
• initiating a flow of an injection of medical substance through said single lumen of said needle device, said single lumen having a substantially constant diameter along an entire length of said porous distal end;
• and,
• restricting said flow at an end region of said distal end so as to cause said medical substance to weep and ooze from said plurality of microholes of said distal end to said injection site in said patient.