Week 6

This week I was able to go to OR and shadowed a couple surgeries. Some of them were really impressing to me. The first surgery was to remove a tumor near spinal cord. In order not to touch the nerve system in spinal cord, the doctors put screws in the vertebra. Also, they partly stimulated the neurons and put them on EMG to make sure those neurons are not effected during the surgery. The second surgery was to drill a hole through nose to remove a big brain tumor. As I saw from MRI images. the brain tumor was really a big one. In order to get rid of it, the surgeons had to cut it into pieces, and then took them out piece by piece.

Besides surgery shadowing, there are also some updates on my project. As I have mentioned in my previous bloggers, watershed algorithms work the best for my project, automatic image segmentation of zebra fish neuron images. However, this algorithm is very sensitive to noise, resulting in over segmentation in regions with low SNR. In order to overcome this problem, I tried other algorithm based on watershed transform, watershed-based neutrosophic approach. However, this method also couldn't deal with noise. In those regions with low SNR, watershed algorithm usually generate large regions instead of small regions of each neuron. Inspired by that, I thought of an iterative watershed algorithm, which applies watershed to those large regions resulting from initial watershed applied to the whole image. However, this idea didn't work out, because the second-step watershed is problematic. Then I tried another region growing based algorithm for the second step. It worked out better than only just apply watershed. The results are attached here.
Fig: Result of only applying watershed.

Fg2: Result of applying region growing based method to large regions resulting from watershed.

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