Fig 1.
The scenario of using TrachyPen to perform the PDT procedure robotically.
Table 1.
Potential improvements of current PDT and device design requirements for a puncture and dilation device [28].
Fig 2.
Four steps of using TrachyPen to complete the PDT procedure.
Step 1: puncture; Step 2: needle retraction and guidewire insertion; Step 3: dilation; Step 4: TrachyPen disengage and manual tube insertion.
Fig 3.
Overview of the mechanical design of TrachyPen.
(A) TrachyPen can be used by rotating the handle manually or with motor assistance. (B) The stoma created by the puncture is expanded by the sliding movement of two dilator arms controlled by a cam. Dilator arms remain closed by two compressed springs. (C) The needle is extended through an S-shape slot for puncture and retracted during dilation.
Fig 4.
Experiments of TrachyPen evaluation.
(A) Experimental setup. (B) Overview of the TrachyPen prototype in the automatic mode. (C-D) A Ciaglia Blue Rhino and a blunt dilator were installed on the robot to perform simulated PDT dilation. (E) The tissue fixing rig. The porcine skin samples are mechanically fixed using screws and the cap. The insertion is to be placed through the mm hole. (F-H) Insertions of the blunt dilator, Ciaglia Blue Rhino and TrachyPen on the porcine back skins.
Fig 5.
Results and data distributions of simulated TrachyPen CBR dilation on porcine back skins.
(A) Sample thickness of Ciaglia Blue Rhino and TrachyPen groups. (B) Stoma length of Ciaglia Blue Rhino and TrachyPen groups. (C) Insertion force peak of Ciaglia Blue Rhino, TrachyPen and blunt dilator. (D) Motor output during TrachyPen dilation.
Table 2.
Experimental outcome of TrachyPen and Ciaglia Blue Rhino dilations on porcine back skins.