Abstract: A single-use electronic endoscope has a hub, a shaft extending from the hub, flexible or rigid as desired, and an expandable distal tip extending from the shaft. Within the distal tip, an image sensor provides a field of view external from the endoscope. Illuminating elements or light guides within the distal tip emit light to illuminate the field of view. The distal tip also has a variable profile working channel that permits tools to be passed from the hub and into the field of view. The expandable working channel changes cross-sectional shape from a generally noncircular shape to a shape to accommodate the cross-sectional shape of the tool when expanded.