Recurring Meeting of Cleveland Clinic Core Team

Date: May 6, 2014

Time: 10:30 AM EST

Means: In person meeting

Attendees:

1. Ahmet Erdemir
2. Jason Halloran
3. Craig Bennetts
4. Snehal Chokhandre
5. Elvis Danso
6. Robb Colbrunn
7. Tara Bonner

Agenda:

1. Discuss immediate action items from the last meeting.
2. Update on robotics maintenance for joint mechanical testing.
3. Review of tissue testing specifications.
4. Review of specimen preparation specifications.
5. Decide immediate action items for the next meeting.
6. Other.

Immediate Action Items:

• Ahmet
  • Follow-up with Jason on patella marker assembly coordinate systems; divot based or spherical marker based.
  • Setup biweekly meetings with Jason and Craig to work on modeling specifications.
• Snehal
  • Update tissue testing specifications to reflect discussions on tissue thickness measurement.
  • Start providing protocol details for tissue testing.
  • Provide quantitative information on image-based tissue thickness measurement.
  • Order base plate for confined compression and tall bath with flat walls.
• Elvis
  • Provide specific protocol details for indentation testing of tissues.
• Jason
  • Provide quantitative information on patella marker assembly in the relevant infrastructure page.
• Tara
  • Respond to Ahmet's request for information in joint testing specifications.

• Craig & Ahmet

  • Meet to define a test problem for cloud computing incorporating post-processing.

• Jason & Robb

  • Meet to conduct actual calibration of the pressure measurement system.
  • Finalize documentation of pressure measurement calibration.

Notes:

1. Discuss immediate action items from the last meeting.
   • Ahmet informed the team that Shannon (from University Hospitals) have sent an e-mail indicating that they don't currently have adequate time on the machine to extract all image acquisition parameters. In the meantime Ahmet updated and organized the imaging specifications page. The imaging settings were divided into individual protocols and the corresponding tables to summarize imaging parameters will be filled in. A discussion page now includes all the previous iterations and trials for the previous imaging test sessions. The final procedure and specifications will be completed once Ahmet receives image acquisition parameters.
   • Ahmet also updated the registration page, which focuses solely on establishing coordinate system transformations between the image and experimental coordinate frames. A Python script needs to be developed to fit point clouds to a sphere (obtained from MRI or by Optotrak probing). For patella registration marker assembly, Jason will add divot to sphere centers transformation, which is a fixed transformation based on the CAD geometry.
   • Snehal has an updated list of tissue testing accessories, fixtures, clamps and the relevant infrastructure. The lab setup is progressing. The eye wash station is in process, the table has arrived, chairs have not arrived but are ordered. Pilot testing is moving along. A taller bath was made for tensile testing and an aluminum base plate was manufactured to glue the compression specimens. Indenters were also made yesterday. Manufacturing of a spherical indenter is uncertain. Manufacturing of the confined compression base plate is pending; this may be needed soon for testing and Snehal will talk to Tony (from Prototype Laboratory) to follow up.
   • The team discussed tissue testing needs to support Elvis Danso's experiments:
     • Both of Elvis's specimens were delivered yesterday. The plan is to test one knee before Elvis leaves. The specimens are one female (46 years old) and one male (56 years old).

     • Snehal and Elvis performed some preliminary tests last week. The stress-relaxation protocols appear to be working except some unexpected data points during relaxation. It seems that the displacement value switches signs sporadically. Snehal informed BioMomentum, Inc. about this issue.

     • The tissue testing machine, if checked, filters the force data and reports filtered information. This can induce a phase shift. Ahmet collected data with the filter off. The raw data should be collected at all times. If a threshold type test is desired, the threshold value should be specified considering the resolution of the system.

     • Elvis updated the group on indentation testing of the medial meniscus. In the trial test, the force values were quite small and resulted in a fair amount of noise due to force transducer resolution. Elvis thinks the indentation may not go beyond the toe region, though a precompression value of 50 grams was applied. Ahmet wondered if the force transducer (load cell) could be calibrated to a lower range. The meniscus loading data appears to be near the resolution of the transducer. Various solutions were discussed including talking to BioMomentum, Inc. about this issue. Robb and Tara thought that there may be a parameter in the configuration files that may help with this issue, which essentially acquires the data in a lower range of force values at a better resolution.

     • Tensile testing appears to be working well. The related specifications need to be populated so that there are no questions during the testing for Elvis. Compression testing, and the related resolution issue, needs to be worked out. One solution is to increase indenter size; another to do unconfined/confined test with relatively large meniscus sample size. For cartilage, Elvis may need to change his protocol to confined/unconfined compression of prepared samples instead of bone-cartilage regional samples that are compressed with the indenter.
     • Elvis will update the indentation protocols. Snehal will reflect some of these discussions in the Open Knee(s) specifications.
     • Additional tissue adhesive was ordered and the image processing for specimen geometry measurements needs to be finished.
     • In regard to tissue testing specifications, Snehal will update the relevant wiki page to reflect discussions on the image based tissue thickness measurements and testing of ligaments, including protocols for previous trials.
   • Jason and Robb will meet this week to finish the pressure measurement equilibration/calibration routine.
   • Regarding registration, Jason will write a report to summarize the patella registration issue (this should be included in the infrastructure page). To support this activity, Craig probed points on the MRI of the patella registration maker.
   • Tara and Dylan uploaded documentation on robot control and execution reproducibility. Last Friday, Dylan and a visiting high school student conducted some tests on the repeatability of the cameras, the repeatability of probing a given point, and the creation of a world coordinate frame based on multiple probed points. Except for the latter, the errors were quite small from a practical perspective. The inaccuracy for the latter may ay be a field of view issue and a report will follow to explore this matter in more detail. Tara has been working on the gravity compensation issue. The motor brake fix needs to be updated; the manufacturer will be contacted to find out when the new motors will be delivered. In theory (per Robb's estimate), the motors should arrive by June 3, 2014
2. Update on robotics maintenance for joint mechanical testing.
   • Refer to discussions above on immediate action items from the last meeting.
3. Review of tissue testing specifications.
   • Refer to discussions above on immediate action items from the last meeting.
4. Review of specimen preparation specifications.
   • The group needs to read this page individually. Next week we will go over this page all together and decide on the final action items relevant to finalize it.
5. Decide immediate action items for the next meeting.
   • Action items were assigned and agreed upon. See Immediate Action Items above.
6. Other.
   • Ahmet and Craig will meet to discuss outlining a test problem to implement post-processing as part of the cloud computing infrastructure. The next meeting with team at Stanford University is in two weeks.
   • Ahmet will schedule a bi-weekly meeting with Craig and Jason to focus on modeling specifications.
   • The roadmap timeline will be updated by Ahmet. It seems like the schedule needs to be pushed back by three months.