A flow mixing device for use with first and second injection fluids, the flow mixing device comprising: a housing having a proximal end opposite a distal end along a longitudinal axis, and a first portion at the distal end and a second portion at the proximal end, the first portion and the second portion joined together at a seam extending around an outer perimeter of the housing about the longitudinal axis, wherein the first portion of the housing has a substantially conical proximal end and a substantially cylindrical distal end, a radial collar surrounding a base on one of the first portion and the second portion, and a flange on the other of the first portion and the second portion such that the flange is received within the collar so that the first and second portions are joined together at the seam, a first fluid port provided at the proximal end and configured for receiving the first injection fluid; and a second fluid port provided at the proximal end and configured for receiving the second injection fluid; the first fluid port and the second fluid port being substantially parallel with the longitudinal axis and radially offset relative to the longitudinal axis; a mixing chamber disposed within the housing between the proximal and distal ends, the mixing chamber being in fluid communication with the first and second fluid ports for mixing the first and second injection fluids; a third fluid port provided at the distal end and in fluid communication with the mixing chamber for discharging a mixture of the first and second injection fluids to allow the mixture to be injected into a patient; and a turbulent flow inducing member comprising a flow dispersion device and being disposed within the mixing chamber characterized in that the flow dispersion device has a stem and two deflection members (242a, 244a), the stem being positioned between the first and second fluid orifices (226a, 228a) and extending in a longitudinal direction toward the distal end of the first portion and the deflection members (242a, 244a) extending radially outward from the stem, wherein a transitional portion is present between the stem and the radially-extending deflection members (242a, 244a) and the transitional portion is curved to gradually transition the flow of the first and second injection fluid from a substantially longitudinal direction to a substantially radial direction with respect to a central axis of the mixing chamber; a radial space is provided between the terminal end of each deflection member (242a, 244a) and the sidewall of the mixing chamber 212a, the first and second injection fluids being deflected to flow from a substantially longitudinal direction to a substantially radial direction by the deflection members (242a, 244a) and being forced to flow through the radial space 246a. a housing having a proximal end opposite a distal end along a longitudinal axis, and a first portion at the distal end and a second portion at the proximal end, the first portion and the second portion joined together at a seam extending around an outer perimeter of the housing about the longitudinal axis, wherein the first portion of the housing has a substantially conical proximal end and a substantially cylindrical distal end, a radial collar surrounding a base on one of the first portion and the second portion, and a flange on the other of the first portion and the second portion such that the flange is received within the collar so that the first and second portions are joined together at the seam, a first fluid port provided at the proximal end and configured for receiving the first injection fluid; and a second fluid port provided at the proximal end and configured for receiving the second injection fluid; the first fluid port and the second fluid port being substantially parallel with the longitudinal axis and radially offset relative to the longitudinal axis; a mixing chamber disposed within the housing between the proximal and distal ends, the mixing chamber being in fluid communication with the first and second fluid ports for mixing the first and second injection fluids; a third fluid port provided at the distal end and in fluid communication with the mixing chamber for discharging a mixture of the first and second injection fluids to allow the mixture to be injected into a patient; and a turbulent flow inducing member comprising a flow dispersion device and being disposed within the mixing chamber characterized in that the flow dispersion device has a stem and two deflection members (242a, 244a), the stem being positioned between the first and second fluid orifices (226a, 228a) and extending in a longitudinal direction toward the distal end of the first portion and the deflection members (242a, 244a) extending radially outward from the stem, wherein a transitional portion is present between the stem and the radially-extending deflection members (242a, 244a) and the transitional portion is curved to gradually transition the flow of the first and second injection fluid from a substantially longitudinal direction to a substantially radial direction with respect to a central axis of the mixing chamber; a radial space is provided between the terminal end of each deflection member (242a, 244a) and the sidewall of the mixing chamber 212a, the first and second injection fluids being deflected to flow from a substantially longitudinal direction to a substantially radial direction by the deflection members (242a, 244a) and being forced to flow through the radial space 246a.