Week 6: High Five for HiFU!

This week I added the additional patients to get a total of 16 patients and did SUV and texture analysis comparison on them. I did not observe any positive linear correlation between the SUV and MR pixel intensities between the patients. However, there seemed to be a positive correlation between histogram energy, entropy and mean in the PET prostate regions and the MR regions. In the upcoming week, I will add three more patients to the study and find the best fit model that relates texture features between PET and MR, and quantify the goodness of the fit. In addition, with the exception of a outlierm there was also a positive correlation between the Pi-Rads score and the SUV pixel intensity. The Pi-Rads score is like the Gleason score in ranking cancer cells based on their pathology slides, but it is based on looking at the MR images of prostate cancer only. This correlation matches what we predicted since only cancerous lesions are bright in PET scans, and highky invasive cancers will have a high Pi-Rads score, therefore, it makes sense that a higher Pi-Rads score will correspond to a higher SUV intensity.

I also got to have a tour of the Citigroup B

iomedical Imaging Center (CBIC), given by Dr. Doug Ballon. We saw an MRI while it was on, and observed the magnet’s magnetic field lines by bringing our Cornell name tags with a metal end close to the center of the machine. The magnetic forces pulled the metal end of the tag close to the machine, and as we moved the tag, the metal would move also to align itself with the magnetic field lines. We also put a silver dollar coin standing up inside the machine. The coin very slowly fell down, because the magnetic field inside machine combined with the improper induction within the coin caused a changing magnetic field inside the coin which caused a counterclockwise voltage which then causes a magnetic force in the opposite direction to that of the MR magnet. We also saw a $2 million high-intensity focused ultrasound (HIFU) machine for treating essential tremors. This condition causes shaking, mostly in, the hands head, voice or legs. The HIFU is operated by a neurosurgeon and focuses a 0.25-2 MHz ultrasonic beam, with a 1.5 cm diameter, on the patient’s brain. The highly focused beam created a high heat buildup in the region. Although bone is a material that absorbs the ultrasound wave, MR is able to detect the heat maps and guide the beam placement, to prevent overheating. The beam reaches the thalaus, which is located near the center of the brain and is used to noninvasively ablate the erroneous neurons that cause the shaking. The effects are immediate so patients can perform tests to check whether the procedure worked right after. We also saw a cyclotron, that is used to produce the radioactive materials which are bonded to the molecules that will bind to the body during specific PET imaging. Next week, I hope to see more interventional radiology surgeries, finish my research project, win another escape room and see Aladdin on Broadway!