Table of Contents

Force-Sensing Drill For Skull Base Surgery

Last updated: February 16, 2021

Summary

We are developing a force-sensing drill attachment for the Anspach + Galen used during Skull-Base Surgery

Background, Specific Aims, and Significance

The Galen Robot is a hand-over-hand cooperative controlled surgical robotic system used for head and neck surgery. This system combines the precision and dexterity of a robot with the cognition and intelligence of a surgeon. For surgeries around the skull base, any tremor, jerk, or overshoot could have serious consequences on the patient outcome.

Additionally, the forces applied by the surgeon to the bone during drilling operations can be extremely small and hard to control precisely, especially for surgeons with less experience. Thus, there is a need for a device that can precisely measure a critical range of forces that are applied during the most sensitive parts of the surgery.

This sensor can be used to help train residents, by demonstrating the difference between the forces applied by residents and expert surgeons. In the future, we intend for this sensor to be used in conjunction with the Galen Robot. Based on the forces measured by this sensor, virtual fixtures and other forms of haptic feedback can be delivered to the surgeon in order to improve their perception of the magnitude of the forces they are applying.

Deliverables

Technical Approach

Data Acquisition & Analysis:

The current literature describing the tool-tissue interaction forces during skull-base surgical procedures is very limited. To this end, we will be performing multiple drilling experiments to understand the magnitude and range of forces exerted onto the tissue.

For the first experiment, a chicken egg is placed in a fixture, which is rigidly attached to an ATI Nano 17 6-DOF Force/Torque sensor. The surgeon drills small holes in the egg shell without piercing the inner membrane of the egg. In previous literature, it has been demonstrated that egg shells display similar properties to inner-ear anatomy. Thus, using eggs as a drilling specimen provides a cheap and effective outlet to refine the experimental setup in preparation for drilling experiments with a real temporal bone.

For the second experiment, the chicken egg is replaced with a temporal bone. The surgeon then performs a mock mastoidectomy.

We determined it appropriate to also consider the torques being applied to the force sensor. To account for the torques, we will be conducting drilling experiments with an Atracsys system to track the position of the drill with respect to the Force/Torque sensor. Knowing the position of the drill with respect to the sensor, we can calculate the moment arm and forces which contribute to the torque readings on the sensor. We can then combine this force vector with the force readings from the sensor to get a very accurate representation of the tool-tip interaction forces.

Mechanical Design:

We are currently exploring two parallel design branches. Both branches rely on deformation or displacement between an inner shell rigidly fixed to the drill and an outer shell held by the surgeon. The outer shell is connected to the inner shell either via carefully engineered flexural members (branch 1) or an off-the-shelf 6-DoF force/torque sensor (branch 2).

The design of flexural elements and the selection of strain gauges, DAQ, or off-the-shelf sensors will be based on the data analysis described above. Initial design of flexural elements will use approximations based on simplified beam theory, and we will use finite element analysis to inform the final selection of materials and geometry.

We will also be working closely with surgeons to iterate on the design of the outer shell to ensure an ergonomic design that minimizes obstruction to their view of the drilling site.

Prototyping:

Initial rapid prototyping will be carried out using the 3-D printer in the Robotorium and the LCSR machine shop. If any parts need to be prototyped using a CNC machine, we will consult the professional machine shop located on campus. Depending on cost and turnaround time, we may choose to outsource prototyping or machining to an external firm such as Xometry or Protolabs.

Dependencies

Milestones and Status

Report on drilling data analysis results (Expected: March 3)

Get surgeon feedback on first prototype(Planned: March 3, Expected: March 8)

Propose budget (Expected: March 5)

Conduct drilling experiment with Atracsys (Planned: March 17, Expected: March 26)

Report on atracsys drilling data experiment (Expected: April 9)

Select off-the-shelf components and record it in a BOM (Expected: March 26)

Progress Pictures

Reports, Presentations, Relev

Project Bibliography

[1] T. B. C Gaudeni, GM Achilli, M Mandala, D Prattichizzo, “Instrumenting Hand-Held Surgical Drills with a Pneumatic Sensing Cover for Haptic Feedback,” Cham, 2020: Springer International Publishing, in Haptics: Science, Technology, Applications, pp. 398-406. 

[2] R. M. H Sang, E Wilson, H Fooladi, D Preciado, K Cleary, “A New Surgical Drill Instrument With Force Sensing and Force Feedback for Robotically Assisted Otologic Surgery,” Journal of Medical Devices, vol. 11, September 2017.

[3] J. H. M Hessinger, PP Pott, R Werthschutzky “Handheld Surgical Drill With Integrated Thrust Force Recognition,” presented at the IEEE International Conference on E-Health and Bioengineering, Grigore T Papa University a/Medicine and Pharmacy, Iasi, Romania, November 21-23,2013, 2013.

[4] S. L. Y Guo, JB Mann, “Piezo-Actuated Modulation-Assisted Drilling System With Integrated Force Sensing,” Journal of Manufacturing Science and Engineering, vol. 139, January 2017 2017.

[5] R. L. D Schurzig, A Hyssong, T Rau, RJ Webster III, “Design of a Tool Integrating Force Sensing With Automated Insertion in Cochlear Implantation,” presented at the IEEE/ASME Transactions on Mechatronics, 2012.

[6] I. D. M Louredo, JJ Gil, “DRIBON: A mechatronic bone drilling tool,” Mechatronics, vol. 22, no. 8, pp. 1060-1066, 2012, doi: doi.org/10.1016/j.mechatronics.2012.09.001. [7] L. W. PJ Berkelman, RH Taylor, P Jensen, “A Miniature Instrument Tip Force Sensor for Robot/Human Cooperative Microsurgical Manipulation with Enhanced Force Feedback,” presented at the IEEE Transactions on Robotics and Automation, October 2003, 2003. [8] J. R. DL Rothbaum, D Stoianovici, P Berkelman, GD Hager, RH Taylor, LL Whitcomb, HW Francis, JK Niparko, “Robot-assisted stapedotomy: Micropick fenestration of the stapes footplate,” Otolaryngology– Head and Neck Surgery, vol. 127, 5, pp. 417-426, 2002. ======Other Resources and Project Files====== Here give list of other project files (e.g., source code) associated with the project. If these are online give a link to an appropriate external repository or to uploaded media files under this name space (2021-08).