Treatment method and device with ultrasound endoscope

An access device used with an endoscope, comprising:

• an access pipe configured to be inserted into a sheath of the endoscope;
• a piercer disposed on a distal end portion of the access pipe and configured to pierce into a hollow organ of a patient through a digestive tract of the patient;
• a treatment tool configured to be inserted into the access pipe and to be introduced into the hollow organ by the piercer;
• and
• a stylet that is disposed inside the access pipe and electrically connected to the piercer
• wherein the access device is switchable between a first configuration and a second configuration,
• wherein the piercer includes an energy device configured to be turned on in the first configuration,
• wherein, in the first configuration, the stylet is configured to activate the energy device to pierce the piercer into the hollow organ,
• wherein, in the second configuration, the stylet is configured to deactivate the energy device, and is configured to advance the piercer away from the access pipe to create an opening between the piercer and the access pipe of sufficient dimension to introduce the treatment tool into the hollow organ via the opening, and
• wherein, in the first configuration, the opening between the piercer and the access pipe is closed.