Medical systems and devices having an articulable external channel and related methods of use

A medical system comprising:

• a first medical device comprising:
• a handle;
• and
• a shaft extending distally from the handle, wherein the shaft includes a longitudinal axis, an articulation section, and a distal tip;
• and
• a second medical device extending distally alongside at least a portion of the shaft of the first medical device, the second medical device comprising:
• a distal portion including a channel;
• a first cable;
• and
• a second cable,
• wherein the first cable and the second cable are configured to move proximally or distally to move the channel between a first configuration and a second configuration, and wherein, in the first configuration, the channel of the second medical device is aligned with the longitudinal axis of the shaft of the first medical device, and wherein, in the second configuration, the channel of the second medical device is at a non-zero angle relative to the longitudinal axis of the shaft of the first medical device.

A method of treating a target site:

• delivering a medical system to the target site, the medical system comprising a first medical device and a second medical device, wherein the second medical device is coupled to at least a portion of the first medical device;
• articulating a distal portion of the first medical device to a first position;
• advancing a first medical instrument through a working channel of the first medical device;
• articulating a distal portion of the second medical device to a second position independent of the distal portion of the first medical device;
• and
• advancing a second medical instrument through a channel of the second medical device.