Transvitreal subretinal injector

An apparatus, comprising:

• (a) a body;
• (b) an outer cannula extending distally from the body;
• (c) an inner cannula slidably disposed in the outer cannula for translating longitudinally relative to the outer cannula, wherein the inner cannula includes:
• (i) an open proximal end,
• (ii) an open distal end configured to pierce a layer of an eye of a patient to access a subretinal region of the eye, and
• (iii) a lumen extending between the open proximal end and the open distal end, wherein the lumen is configured to communicate first and second fluids from the open proximal end to the open distal end for delivering the first and second fluids into the subretinal region of the eye;
• and
• (d) a fluid supply assembly including:
• (i) first and second proximal fluid supply passageways configured to be selectively fluidly coupled to the lumen of the inner cannula for supplying the first and second fluids, respectively, to the lumen, and
• (ii) first and second Belleville valves configured to selectively fluidly couple the first and second proximal fluid supply passageways, respectively, to the lumen of the inner cannula.