Second Week of Immersion

For this week, my clinical mentor, Dr. Susan Gauthier, was out of town. In the meantime, I was working on creating the PET kinetic model with phantom data until I was able to receive actual data to begin analysis on. Outside of working on the project, I was able to shadow Dr. Ted Schwartz to see a neurosurgery being done where a tumor was removed from near the brain through a hole drilled along the wall of the patient's nose. What impressed me most of the surgery was not the procedure itself but one of the guiding tools used in which the patient's MRI was mapped to a probe that allowed the surgeons to accurately locate the tumor for removal. From what I had seen, the probe used electrode sites located on the head of the patient to calibrate the positioning of the probe to a previous MRI on file. From there, the surgeons could see on a screen, the MRI indicating the location of the tip of the probe, shown in below (Ivanov et al, 2017).

Today, though, I was able to observe MR data acquisition of a variety of cases and even saw some of the limitations of using MRI in terms of patient comfort or safety. Some of the limitations were what one would expect: claustrophobia, movement during acquisition, and some patients not being able to fit into the machine as mentioned by one of the technicians. What I did not expect was the limitation from patients not being able to breathe lying down, in other cases having sleep apnea so that even anesthesia was risky, or the unreliable tendencies of monitors to be used for patients that had to be anesthetized. The anesthesiologist complained that many times, the monitors would not function and in times when it does, specific signals were reduced in quality as shown below where the EKG signals varied from having the full signal to barely being noticeable on the monitor.



The anesthesiologist gave a couple ideas to work on (a wireless monitor in the OR or a compatible monitor for MRI), but it may not be a project that I could take up and each has limitations to overcome.

So far, though immersion has been slower than I anticipated, things are picking up and going much better.

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