Medical instrument for fluid injection and related method
A medical instrument for fluid injection includes a tubular member and a plurality of hollow needle elements connected to one end of the tubular member. Generally, the tubular member has a lumen and all the needle elements communicate with the lumen to enable a distribution of a diagnostic or therapeutic fluid to various points in a predetermined region. The tubular member is provided with a fluid introduction port at an end of the tubular member opposite the needle elements, the fluid introduction port communicating with the lumen. The needle elements are disposed in a predetermined configuration adapted to carry out a desired function. The needle elements are at least partially made of resilient material with a memory so that the needle elements are biased by their internal stresses towards a predetermined rest configuration and are alternately disposable in the rest configuration and at least one stressed or loaded configuration.
1. An endoscopic medical instrument comprising an elongate tubular member containing a lumen extending from a proximal end to a distal end and a plurality of hollow needle elements connected to one end of said elongate member so that each of said hollow needle elements communicates at a proximal end with said lumen of said elongate tubular member, said elongate tubular member being sufficiently flexible, long and narrow to traverse a biopsy channel of a flexible fiberoptic endoscope, said needle elements extending in a direction away from said one end of said elongate tubular member, said needle elements each being convex on an outer side facing away from others of said needle elements and concave on an inner side facing said others of said needle elements so that said needle elements together define a bulbous ovoid shape, with tips of said needle elements angled inwardly at a distal tip of the medical instrument, said needle elements each being sufficiently flexible to negotiate bends in said biopsy channel, each of said hollow needle elements being provided with at least one aperture so that fluid may be delivered through said elongate tubular member into said hollow needle elements and out through the apertures in said hollow needle elements.
2. The medical instrument defined in claim 1 wherein said needle elements are at least partially made of resilient material with a memory so that said needle elements are alternately disposable in (a) a collapsed storage configuration inside said elongate member and (b) said bulbous ovoid shape.
3. The medical instrument defined in claim 2 wherein said needle elements are disposable in said storage configuration by the application of an external force, said needle elements having an internal spring bias tending to restore said needle elements to said bulbous ovoid shape.
4. The medical instrument defined in claim 1 , further comprising at least one straight or linear hollow needle element connected to said elongate member proximate to said one end thereof, said at least one straight or hollow linear needle element being provided with at least one aperture.