An injection catheter assembly comprising: an elongate flexible outer tube body including: a distal length configured to indwell a patient body trunk cavity; a sealing cuff provided on an outer surface of the outer tube body proximal to the distal length; and at least one body lumen extending longitudinally through at least a lengthwise portion of the distal length, the lumen substantially defined by an inner diameter surface of the outer tube body; the distal length including a plurality of apertures disposed through a wall of the outer tube body and in fluid communication with the body lumen to provide an injection portion to permit passage therethrough of an inner cannula body for dispensing a dispensable medicament; and a flexible, curved inner cannula body dimensioned for passage through the body lumen of the outer tube body, the inner cannula body including: a memory-material portion imposing a pre-determined curve along a length of the inner cannula body; an injection lumen extending longitudinally through at least a lengthwise portion of the inner cannula body; and at least one distal-region opening (246, 249a, b, c) configured for dispensing the dispensable medicament, wherein the inner cannula body is disposed through one of the plurality of apertures into the body lumen and through at least a lengthwise portion of the distal length. an elongate flexible outer tube body including: a distal length configured to indwell a patient body trunk cavity; a sealing cuff provided on an outer surface of the outer tube body proximal to the distal length; and at least one body lumen extending longitudinally through at least a lengthwise portion of the distal length, the lumen substantially defined by an inner diameter surface of the outer tube body; the distal length including a plurality of apertures disposed through a wall of the outer tube body and in fluid communication with the body lumen to provide an injection portion to permit passage therethrough of an inner cannula body for dispensing a dispensable medicament; and a distal length configured to indwell a patient body trunk cavity; a sealing cuff provided on an outer surface of the outer tube body proximal to the distal length; and at least one body lumen extending longitudinally through at least a lengthwise portion of the distal length, the lumen substantially defined by an inner diameter surface of the outer tube body; the distal length including a plurality of apertures disposed through a wall of the outer tube body and in fluid communication with the body lumen to provide an injection portion to permit passage therethrough of an inner cannula body for dispensing a dispensable medicament; and a flexible, curved inner cannula body dimensioned for passage through the body lumen of the outer tube body, the inner cannula body including: a memory-material portion imposing a pre-determined curve along a length of the inner cannula body; an injection lumen extending longitudinally through at least a lengthwise portion of the inner cannula body; and at least one distal-region opening (246, 249a, b, c) configured for dispensing the dispensable medicament, wherein the inner cannula body is disposed through one of the plurality of apertures into the body lumen and through at least a lengthwise portion of the distal length. a memory-material portion imposing a pre-determined curve along a length of the inner cannula body; an injection lumen extending longitudinally through at least a lengthwise portion of the inner cannula body; and at least one distal-region opening (246, 249a, b, c) configured for dispensing the dispensable medicament, wherein the inner cannula body is disposed through one of the plurality of apertures into the body lumen and through at least a lengthwise portion of the distal length.