Apparatus for subretinal administration of therapeutic agent via a curved needle

An apparatus, comprising:

• (a) a body;
• (b) a cannula extending distally from the body, wherein the cannula is flexible, wherein the cannula is sized and configured to advance between a sclera and a choroid of a patient's eye, wherein the cannula has a generally rectangular cross-sectional shape that is configured to prevent the cannula from rotating as the cannula is inserted into the patient's eye, wherein the cannula includes:
• (i) opposing inner and outer surfaces,
• (ii) a closed distal end,
• (iii) a lateral opening located proximal to the closed distal end, and
• (iv) a needle guide that is coupled with the inner surface of the cannula, wherein the needle guide is made from a different material from the cannula, wherein the needle guide does not extend into the lateral opening;
• and
• (c) a needle slidably disposed in the cannula, wherein the generally rectangular cross-sectional shape of the cannula is configured to ensure that the needle exits from the lateral opening of the cannula in a predictable direction, wherein the needle is configured to extend through a lumen of the needle guide, wherein the needle includes:
• (i) a sharp distal tip, wherein the needle is configured to translate relative to the cannula between a proximal position and a distal position, wherein the distal tip is configured to be positioned inside the cannula when the needle is in the proximal position and wherein the distal tip is configured to extend past the lateral opening when the needle is in the distal position, and
• (ii) a curved portion, wherein the curved portion is configured to provide an oblique exit angle to a portion of the needle extending past the lateral opening when the needle is in the distal position.

An apparatus, comprising:

• (a) a body;
• (b) a cannula extending distally from the body, wherein the cannula is flexible wherein the cannula is sized and configured to advance between a sclera and a choroid of a patient's eye;
• (c) a needle slidably disposed in the cannula, wherein the needle includes:
• (i) a sharp distal tip, wherein the needle is configured to translate relative to the cannula between a proximal position and a distal position, wherein the distal tip is configured to be positioned inside the cannula when the needle is in the proximal position and wherein the distal tip is configured to be positioned outside the cannula when the needle is in the distal position,
• (ii) a curved portion, wherein the needle is resiliently biased to extend along a curve through the curved portion, wherein the curved portion is resiliently biased to define a constant radius of curvature, wherein the constant radius of curvature is between 9 mm and 11 mm when the curved portion is disposed outside of the cannula;
• and
• (d) an actuator configured to distally advance the needle relative to the cannula between approximately 0.25 mm and approximately 10 mm to position the needle at a predetermined location within the patient's eye.