Automatic Liquid Injection System and Method

Abstract

A power assisted method and injector device for controllably delivering to patients a dispersion medicament or diagnostically active agent, the homogeneity of which is preserved throughout delivery. Diagnostically active agents disclosed are gas microbubble suspensions useful in ultrasonic diagnostic imaging and liposomal formulations in which liposome vesicles are loaded with iodinated compounds.

1 . A method of administering to patients by injection or infusion a suspension of microparticles homogeneously distributed in an aqueous liquid carrier by means of an injector system comprising a syringe containing said suspension and a power driven piston for injecting said suspension into a patient, characterised by subjecting the syringe containing the suspension to a rotation or rocking motion, thereby maintaining said suspension homogeneous by preventing segregation of the microparticles by gravity or buoyancy, this being without damaging said microparticles or disturbing their distribution. 
     
     
         2 . The method of  claim 1 , in which said rotation or rocking motion is provided by means under motion for supporting the syringe. 
     
     
         3 . The method of  claim 1 , in which said motion of rocking or rotation is alternated. 
     
     
         4 . The method of  claim 1 , in which said motion is applied along or around the syringe longitudinal axis. 
     
     
         5 . The method of  claim 3 , in which said motion is further applied along or around the syringe transverse axis. 
     
     
         6 . The method of  claim 4 , in which said motion is provided by subjecting the syringe to continuous or intermittent rotation. 
     
     
         7 . The method of  claim 5 , in which said motion is provided by subjecting the syringe to continuous or intermittent rotation. 
     
     
         8 . The method of  claim 4 , in which the rotation rate is from 0.5 to 200 rpm. 
     
     
         9 . The method of  claim 5 , in which the rotation rate is from 0.5 to 200 rpm. 
     
     
         10 . The method of  claim 4 , in which said motion is alternating rotation the direction of which is reversed every 30°, 60°, 90°, 180°, 270° or 360°. 
     
     
         11 . The method of  claim 5 , in which said motion is alternating rotation the direction of which is reversed every 30°, 60°, 90°, 180°, 270° or 360°. 
     
     
         12 . The method of  claim 10 , in which the direction is alternated at a frequency of 0.5 Hz, 1.0, Hz, 1.5 Hz, 2.0 Hz, 2.5 H2, 3.0 Hz or 3.5 Hz. 
     
     
         13 . The method of  claim 11 , in which the direction is alternated at a frequency of 0.5 Hz, 1.0, Hz, 1.5 Hz, 2.0 Hz, 2.5 H2, 3.0 Hz or 3.5 Hz. 
     
     
         14 . The method of  claim 1 , in which said motion is carried out stepwise. 
     
     
         15 - 26 . (canceled) 
     
     
         27 . The method of  claim 1 , in which the suspension is a contrast agent for ultrasonic imaging of patients. 
     
     
         28 . The method of  claim 27 , in which the contrast agent comprises, in suspension in an aqueous liquid carrier, gas filled microvesicles which are either microbubbles bounded by a gas/liquid interface made from dissolved surfactants, or microballoons bounded by a material envelope made of organic polymers, or of di- or tri- glycerides. 
     
     
         29 . The method of  claim 28 , in which the gas is a pure physiologically acceptable halogenated gas or gas mixture comprising at least one physiologically acceptable halogenated gas. 
     
     
         30 . The method of  claim 29 , in which the halogenated gas is selected from CF 4 , C 2 F6, C3F8, C4F8, C4F10, C5F12, C6F14 or SF6. 
     
     
         31 . The method of  claim 29 , wherein the gas mixture contains a gas selected from air, oxygen, nitrogen, helium, xenon or carbon dioxide. 
     
     
         32 . The method of  claim 28 , in which at least one of the surfactants is a saturated phospholipid in a lamellar or laminar form. 
     
     
         33 . The method of  claim 32 , in which at least one of the phospholipids is a diacylphosphatidyl compound wherein the acyl group is a C16 fatty acid residue or a higher homologue thereof. 
     
     
         34 - 43 . (canceled)