A method of prefilling and terminally sterilizing a syringe including providing a syringe barrel having first and second opposite ends where the first end includes a port therethrough with a connector member formed about an exterior of the port and the second end being open. Particulate matter is removed from the interior of the syringe barrel and a cap and stopper are sterilized, the stopper including first and second opposite longitudinal ends. The first end of the stopper is inserted into the second open end of the syringe barrel until the first end of the stopper reaches the first end of the syringe barrel. The syringe barrel then is filled with a desired liquid, such as a medicament or imaging agent, through the port of the first end of the syringe barrel so that substantially no air enters the syringe barrel and where the stopper moves within the syringe barrel from the first to the second ends thereof upon filling. The cap then is connected to the connector member of the first end of the syringe barrel to seal the port and then the syringe barrel, stopper, luer cap and liquid within the syringe barrel are terminally sterilized in a autoclave having a spray over-pressure cycle which maintains pressure about the exterior of the syringe barrel at least equal to the pressure within the interior of the syringe barrel.