The present invention is directed to a device for a portable 
convection enhanced 
delivery system that allows administering liquids to specific locations within the body, especially tissues and tumors also allowing outsubject treatment. The application 
system comprises a portable extracorporal pump with a fluid reservoir that is connected via an infusion 
system to an 
infusion catheter placeable to any tissue or tumor the fluid should be administered to by high flow microperfusion. The 
system enables administration of fluids of any kind by 
convection enhanced delivery also in out-
patient treatment. The system can be used for delivering various drugs, proteins, 
protein toxins, antibodies-for treatment or imaging, proteins in 
enzyme replacement therapy, growth factors and viruses or oligonucleotides in 
gene therapy etc. The application methods as well as the surgical method to 
implant this device are enclosed to this invention.