Figure 1.

(a) Schematic representation of insulin flow (blue) through the investigational prototype extended-wear cannula and out through the four holes. (b) The coil-reinforced wall guarantees flexibility and kink resistance of the cannula. This demonstration shows orange dye flowing through the four holes, even when the 24-gauge cannula is tied in a knot. (c) The investigational IIS prototype with a soft Nylon-derivative cannula and stiff stainless-steel stylet with a sharp needle distal tip. Markings facilitated manual insertion of the 13.5-mm-long cannula into the subcutaneous tissue at an angle of approximately 35°. The stylet was removed after insertion.

Abbreviation: IIS, insulin infusion set.