Abstract: An apparatus includes a shaft assembly and a distal endoscope cap. A flexible distal portion of the shaft assembly is laterally deflectable relative to a rigid proximal portion of the shaft assembly. The shaft assembly defines a working channel sized and configured to enable advancement of a working element. The distal endoscope cap is configured to attach to the distal end of the shaft assembly. The distal endoscope cap has an outer diameter that is larger than the outer diameter of the flexible distal portion. The distal endoscope cap includes a body having at least one coupling member for attaching the distal endoscope cap to the distal end of the shaft assembly, at least one image sensor secured to the body for visualizing an anatomical structure, and at least one illuminating element secured to the body for illuminating a field of view of the at least one image sensor.