Week 7

The last week of the immersion program started with a day in the clinic that involved the usual routine of interviewing patients. After this, I kept working on my literature review for the paper on the study and I managed to complete it throughout the week. I then compiled this review into a one page introduction for the final paper and then sent to my advisor for review. Since, Dr. Kennedy did not actually see any patients for the rest of the week, I took this opportunity to meet with other clinicians at HSS in order to see all of the work being done there. This led me to meeting with Dr. Suzanne Maher whose research is focused on the development of biomaterials for joint restoration. I talked to her about her research and met with some of the people in her lab to learn more about the projects that they are working on. I learned about one particular project that is not currently being led by anyone, which is focused on developing an intra-op sensor to measure the stresses in the knee for meniscectomy patients. This would be to see how the stress profile changes in the knee in response to injury and conditions such as osteoarthritis. I found this to be very interesting and actually met with Dr. Scott Rodeo to learn more about it and see what the difficulties surrounding the sensor would be. Dr. Rodeo then invited me to come into the operating room to witness a knee arthroscopy and a meniscectomy. This was an amazing opportunity which I am incredibly grateful for and I can certainly see now that this sensor has several design criteria it has to take into account in order to be effective. This concluded my time at HSS and I am certainly thrilled about this amazing opportunity! I feel my passion for the medical field has strengthened and I have learned a lot about myself, including that an MD may be something that I may be strongly interested in for the future.

Week 7

This last week we went down to NYP campus in Lower Manhattan (Beekman st) because their MRI scanners have a special metal reduction artifact software that will help us image better the tissue expanders. From the images that we were able to acquire, the metal artifact is reduced significantly, in comparison with our other optimization experiments. This is definitely the way to go for imaging the tissue expanders. The only downside is that the software is only available at 3T MRI, which is contraindicated for patients with tissue expanders. But hopefully Dr. Prince will get a version of the software for 1.5T MRI and he will be able to image his patients with this from now on.
I also finished analyzing all the data I got while being in NYC. I calculated the size of artifact, standard deviation and SNR of all the images to determine which combination of parameters will give us the best images. In conclusion, higher bandwidth and thicker slices gives us the best SNR ratio and less artifact.

I'm feeling very nostalgic to leave tomorrow. I can't describe how much I learnt this summer, how much I enjoyed my experience here and how happy I was.
A great part of that was thanks of my advisor, Dr. Prince. He made my experience here uniquely amazing.  He transmitted me his passion for MRI, and made me feel excited and curious about a subject I had no idea about before coming here. I also learnt about neurosurgery and plastic surgery. I'm definitely eager to keep working with him and finish my work here, hopefully with the submission of a paper or an abstract.

Another great part of that was because of my friends. I felt more bounded to them after this experience, we had an amazing time exploring good food, getting out of escape rooms, enjoying the broadway shows, and walking around the city. I also felt that I could chat and get to know some of my other classmates as well, those with whom I don't share much back in Ithaca.
I met wonderful people at work, and I also made some new friends. I had my family here, and we explored NYC together. Today I'm leaving to Colombia for two weeks, with my heart full of joy and love.

I would like to thank the BME department, Belinda and Kelly, Dr. Prince, Dr. Min and Dr. Wang for making this experience enjoyable for each one of us. It has definitely helped us gain valuable skills and experience for our PhD.

Week 7

The last week of immersion started with trying to continue working on my clinical research project and ended much more exciting. On Thursday, I once again traveled to New Jersey to work with the sheep for the basic science study. This time, the doctors were performing surgery on the animals, which I was excited to be present for. For the first sheep of two, I was even shown how to scrub in so that I could assist with the surgery. It was very confusing what I could and could not touch, the inside of this, the outside of that, don't touch this color blue but this other shade of blue is fine. I couldn't even adjust my own glasses so I eventually had the technician who was present just remove my glasses and put them off to the side. My facemask shot my warm breath right up into my eyes and fogged up my glasses every breath so they had to go. But it was very interesting to be able to help the doctors during the surgery, doing similar things that I have seen the assisting doctor do for Dr. Hartl during surgery on a patient. Both sheep were fine afterwards, but it was a lot more exhausting actively working on the surgery than it was to just stand in the OR for a few hours watching. This was basically the one part of the basic science project that I was not present for initially, so it was a good way to wrap up my summer immersion.

Week 7: I miss hating the city

This is the last week of the immersion term. As a student biomedical engineering, it is a superb experience to be with a doctor and observe how they interact with the patients and perform surgeries. It is also an awesome experience working in the lab trying to find a way to cease epilepsy using optogenetics technique. 

This week, to assist the experiment, we also built an endoscope to image the neurons inside the brain in-vivo. We have 2 attempts by putting a fiber bundle into the mouse brain before without any success of imaging neurons. We may due to the limitation of the sensitivity of the camera or the insufficient laser intensity for fluorescence excitation. We changed the camera this week and we are thrilled to see some bright fluorescence from the mouse brain.

After all, New York City is a nice place to be in. It may not be as gorgeous as Ithaca. The food and the fun that I can have in the city is a what makes it memorable for me.

Week 7: The Final Countdown

In a fitting manner, this final week seemed to be a compilation of all my best experiences over this summer immersion course. On the research side, my project got a total of 16 patients, which is not enough to do a complete statistical analysis but enough to notice some preliminary trends. Honestly, I had so much fun doing this project, I wish I could continue it till the end and see whether the trends I observe are still retained in a larger sample population. The most interesting trends that I saw were, a positive correlation between the Pi-Rads and the SUVmax/SUV peak, and a positive correlation between SUVmax/peak and MR histogram standard deviation and histogram skew. A positive correlation between the Pi-Rads and the SUVmax/SUV peak indicates that as the risk of tumor occurrence as observed from the MRI images increases, more lesions are detected in the PET images. This correlation indicates that some level of tumor invasiveness can be picked up from MRI scans, however, that level needs to be enhanced to be observed with the naked eye. Furthermore, the positive relation between SUVmax/peak and MR histogram standard deviation and skew indicates that highly invasive tumors have increased histogram standard deviation and skew texture features in the MRI scans. Thus, MRI is able to pick up the lesions seen in PET images as texture features. Further analysis will include overlaying a MRI texture map over the PET scan to see whether the lesion and texture locations are located in the same region.

On the clinical side, I got to see another mind blowing interventional radiology procedure called a chronic venous recanalization, where a radio frequency wire is guided into the clotted vein and heat from the wire is used to burn away the clots. That was the first time for the RF wire to be used for that procedure, so it was a very interesting to be able to observe that process.

I also got to enjoy my last week in the city, by going to see Aladdin on Broadway and completing another escape room. Both were amazing moments and I am glad I got to experience them with my friends.

As I was leaving, most people would ask me whether I am excited to go back to Ithaca, and I finally decided that my answer would be “Yes!”. Being in Weill Cornell Medicine was such a great time and gave me an entirely new perspective on how to help patients, that I’m excited to implement these new ideas and changes into my mindset as a researcher. To everyone who made this summer immersion possible, this will undoubtedly be one of my most unforgettable experiences as a graduate student. 

Week 7

The last week of the immersion program has come to an end, and it was definitely one of the most productive weeks here in NYC. All the preparations----IACUC protocol, surgical and rodent cadaver trainings-----payed off as we finally went in to the OR in the animal facility to practice ACLT on live rats. I am very glad that we were able to do this, as I realized that cadaver practices cannot capture the scope of complications on live animal surgeries. I learned how to manage and monitor the depth of anesthesia, when and where to administer pain killers and antibiotics, and all the little details that you can only pick up in a real OR (such as how to effectively maintain sterile barrier, how to minimize pain and discomfort of the subjects, and etc.). One thing I overlooked when I was preparing myself for the live animal training is the importance of monitoring the depth of anesthesia. The depth of anesthesia affects the heart rate and respiratory rate of the animal (the respiratory rate is actually one of the ways to monitor depth of anesthesia), and thus affects the bleeding when incisions are made. Unlike cadavers where there are no bleeding, the live animals can bleed excessively if it is heart rate has not slow down properly from anesthesia, resulting obstructed views by the blood and thus longer and more complicated procedures.

The other good news it that our closed PTOA apparatus is now functional. After numerous iterations and trails and errors, we have finally achieved control speed, displacement and alignment, and ease of operation. As it turns out, the ease of operation was actually more changeling than we originally thought. Because we were modeling our system based on the previously existing PTOA apparatus in rats, we often forget how small mice are. For example, mounting the tibia to the feet clamp is a easy task on rats, but it has proven to be much harder on mice which are around ten times smaller. The size limited the space we can operate, and many mechanisms of stabilizing ended up being too bulky to be practical. Luckily, we gotten it almost figure out by Friday and proceeded to testing on some cadaver mice. Our measurements agrees with the mechanical testing of ACL and the data from the manual methods. However, with manual methods when the force is greater than 10N the PCL are often also ruptured. With our device, we can exert >20N of force and rupture the ACL only, as a result of the controlled displacement. This is great because we know the strength of ACL varies greatly from animal to animal, and with the apparatus, we don’t have to sacrifice the ones with stronger tendons just because we cannot rupture it properly. The ongoing theory of why the manual method always rupture the PCL with the ones of greater force is that once the ACL is ruptured the human hand will accelerate due to the sudden decrease of resistance and hit the PCL. The great the force requires to rupture the ACL (tougher ACL), the greater this acceleration will be and the more likely the PCL will be ruptured. This is precisely why we went to the more controlled methods with a loader in the first place----with a control displacement, no matter the force needed to rupture the ACL, the PCL will remain intact as the loader will never reach it.

I am very happy that all my goals have been accomplished. I am glad that I was able to challenge myself and try new things, both in lab and in life. I had a fantastic summer here in NYC and I will certainly miss the city. In truth, I am already missing it as I am typing my last immersion blog in Newark Airport, but who knows, since my flight has already been delayed for four hours I may never get to leave here after all.  

Week 7

It’s finally happened! It took all of the immersion term, but I was finally able to run some simple models on the data that I had received. It took a while to get to that point after collecting the data – (thanks to finding extra whitespaces in some of your spreadsheets that ends up throwing errors that take 30 minutes to debug), but there are preliminary results now.

Without getting too much in the way of scooping potential future work, preliminary results point to the importance of the perpendicularity of the angle relative to the pleural surface and the use of a collagen plug while finishing the procedure. Of interest is how we can use these results to now attempt to improve patient health prognosis, as both criteria are difficult to always meet – the collagen plug is an additional expenditure of ~500 dollars, and optimizing the angle is not always a feasible task, given the other constraints in place (some trajectories are not feasible) and the inability to discern the precise angle between the pleural surface and the needle along the trajectory to the lesion. Though it’s outside the scope of what I’m capable, we discussed potentially having someone comfortable with image processing design a program that can automatically provide those paths! It would certainly alleviate some of the downfalls of having the operator still decide.

With respect to how some of the analysis was performed – as mentioned previously, the data collected was fit to a logistic regression model. What was done to validate this was a k-fold stratified cross-validation, ie, iteratively, k times, separating the data into a testing set and a training set that still maintains the same ratio of pneumothorax positive samples, ensuring the model is being trained on a representative set of data. As a spoiler to how positive things seem, our predictive accuracy was ~85%!

With these results, it means that I’ll be able to keep having a bit of immersion contact, as we move towards publishing/presenting. It’s a satisfying feeling to have been able to come in and find a novel result in such a short time. Between the research output and the clinical work, this immersion experience has definitely been something I won’t soon forget.

Week 7

In this last week, I tried to identify stromal modifications made by radiotherapy that can elicit different cell behaviors in an attempt to better understand how patient-specific microenvironmental factors could be used to identify patients who might be radioresistant. Identifying such factors would help improve efficacy of treatment in areas the have low alpha/beta ratios like prostate cancers.

In the clinic, I was able to attend surgery with Dr. Spector and see what I would characterize as the most comprehensive demonstration of biomedical engineering’s contributions to medicine that I have seen thus far. In order to repair a mandibular defect left by the removal of a facial tumor, the doctors used a fibular flap to rebuild his mandible and bulk the surrounding tissue. In this one surgery, in addition to the normal technology found in the OR, they used a patient-specific surgical plan that used CT to create an alloy bracket in the shape of his mandible and cutting guides for the fibula. The fibula was isolated from the lower leg and cut into 3 segments, which were attached to the metal bracket and fused to the remaining pieces of the mandible.  They then microsurgically attached blood vessels from the flap to vessels in the neck using an anastomosis device and attached a doppler probe to the vein to monitor blood flow during the first 48 hours. This probe enables them to make sure that the flap maintains a sufficient blood supply to ensure its survival. The probe itself is no doubt a biomedical triumph, but additionally, it is embedded in a biodegradable polymer strap that hydrolyzes and degrades over 48 hours allowing for probe removal without disturbing the new vessel. The entire operation took close to 11 hours to complete and the patient looked unbelievably good afterward.

Reflecting on my immersion experience, I have learned a few things that I had not learned in previous hospital experiences. Most notably, I have seen the complete wholistic approach that doctors must take to addressing patient issues. When a patient comes into radiation oncology, even though it is a referral-based service, they are considering every aspect of a patient’s health when trying to develop a treatment plan or help with discomfort from treatment. Though specialists truly are extremely specialized, they have so much broad knowledge about human biology and general medicine as well as practices that more closely affect their own like medical oncology and surgery. This knowledge is applied systematically, almost as in solving a mystery, to ultimately figure out what is going on and how to fix it.

I am grateful to Dr. Formenti and everyone in Radiation Oncology for showing me the ropes. I learned so much about clinical cancer care that I could never have learned outside of the hospital.

Week 7: Wrapping Up Immersion

In the final week of this immersion experience, it was a bit somber weather with the rain adding to a bittersweet moment. There were a lot of ups and downs to Immersion including a multitude of surgeries, projects, clinics, and exploring of the city. I wrapped up my project with Dr. Cunniff on Bloom’s Syndrome to the best of my ability with the data set given and I feel confident that I created a template for new data to be analyzed by whoever comes after me. Clinical data is far different than working with cells or imaging. You have valuable information of living people and thus brings a heavy amount of responsibility when handling such data. Luckily, my data had already been de-identified, but nevertheless I feel obligated to treat such information with care. I hope I was able to provide some answers or a path to one in this project. Time will only tell.

In review, I wanted to highlight some of the experiences I found extremely valuable or awestriking. Seeing an open heart from above made me appreciate the complexities of the muscles that work for us, especially as someone who studies muscle on the cellular level. Observing a grafting surgery gave me a visual into how engineering can be applied to the body in a clinical setting and inspired future work in tissue engineering. Working with a team of pediatric geneticists provide a clinical perspective on genetic disorders and how they arise. As someone who studies genetics only peripherally, I valued the human aspect of understanding phenotype to genotype and health supervision for those who are affected by such disorders.

New York City is without a doubt the city that never sleeps. To end the summer, I witnessed the city in its full splendor full of lights and wonder and I hope you’ll enjoy what I captured along the way as I have come full circle and am ready to head back home.

Week 7

This week was my final week of immersion, and I have to say I wish that we had at least a couple more weeks here! I spent a significant portion of my time working on the new research project that I mentioned last week in my blog, and was able to get some results. Shown below in Figure 1 are some of the preliminary results of PCI, CABG, and all cardiac surgery caseloads from 1994-2015. In Dr. Tranbaugh and Dr. Ko’s original paper through year 2008, the number of PCI procedures had risen steadily each year, with a small dip between 2007 and 2008 (Ko et al., 2012). It is now clear that the small dip observed before was actually the beginning of a decline in PCI procedures, as shown in Figure 1. Additionally, CABG case numbers have steadily declined throughout the 21-year time period until around 2012, where they appear to have somewhat plateaued. Dr. Tranbaugh said that we can probably submit this and some of the other data I have to a journal whose abstract deadline is in August, and I am very excited!

Figure 1. PCI, CABG, and all-surgery number of cases in New York State from 1994-2015

Procedure-wise, this week I saw a TEVAR, which stands for thoracic endovascular aortic repair. This procedure is performed to repair aneurysms in the aorta minimally-invasively. To repair the aneurysm, a collapsed vascular graft is attached to a catheter, and is threaded into the femoral artery through a large incision in the groin. The collapsed vascular graft is positioned into the location of the aneurysm, and inflated with a balloon into place. For the patient that I saw, the aneurysm was in the descending aorta and was so large it required multiple vascular grafts. A serious complication of this surgery is blocked perfusion to the spinal cord due to the vascular graft, which can result in paralysis of the patient. Unfortunately, the surgeons cannot know whether this has happened until the patient wakes up and tries to move their legs, which seems very stressful and scary to me. Luckily, everything seemed to go according to plan during the surgery.

As it is my last day, I wanted to comment on some overall lessons that I have learned during my immersion term:

1.       Teamwork is essential for physicians. Every surgery has a plan, and everyone implicitly knows what the plan is from start to finish. Also, everyone in the OR seems to have a heightened awareness at all times. If surgery and lab research were sports, I would say surgery is like hockey or basketball, with the surgeon as playmaker, while lab research is like long-distance swimming or track.

2.       All physicians are constantly on their toes, and are able to make decisions in a split second. Even though there is always a plan for every surgery, the plan can change instantly. As someone who is generally a slow decision maker, it was so impressive to see the physicians draw on a multitude of knowledge that they have on-hand at any given moment and make the best decision.

3.       Cardiothoracic surgeons practice and practice their surgeries hundreds of times, until it appears that each procedure is almost second nature. I can see how it could be difficult to implement a new technology surgically as an engineer, because the new technology must be so good that it outweighs the expertise and years of practice that the surgeon has in performing their procedures the conventional way.

4.       There is rarely a dull moment in cardiac surgery! Every week, I was able to see at least one cardiac procedure, if not multiple. This highlights that there is still a widespread need for new cardiovascular disease treatments.  However, it is important to note that from my research, the overall number of PCI and CABG procedures is declining as of 2015. Dr. Tranbaugh speculated that this could be due to improved medical care of patients with coronary artery disease that may have otherwise progressed to surgical patients.

Everyone at the hospital was so sweet to me on my last day in the office at NYPBMH. One of the administrators that I have been working with to set up my immersion paperwork, Anand, ordered a pizza and ice cream cake and everyone got together and ate with me for my last day. I have been so lucky to have such an amazing opportunity to work with Dr. Tranbaugh, Dr. Worku, and everyone in the CT surgery department at NYPBMH, and am certainly going to miss working here. Dr. Tranbaugh was a wonderful teacher, and really made this summer an amazing experience. I feel grateful for all of the surgeries that I have been able to observe, all of the knowledge that Dr. Tranbaugh has given me about general surgical procedures, anatomy, and surgical device development and history, and all of the research I have been able to do with the CT team this summer. I am really going to miss the people, the experiences, and the city when I return to Ithaca tomorrow, and am sad to go.

Source:

Ko, W., Tranbaugh, R., Marmur, J. D., Supino, P. G., & Borer, J. S. (2012). Myocardial revascularization in new york state: Variations in the PCI‐to‐CABG ratio and their implications. Journal of the American Heart Association, 1(2), e001446-n/a. doi:10.1161/JAHA.112.001446

Week 7: Fibular Flaps and Farewells

Biomedical Engineering applications in the OR

Tuesday's case was an excellent example of biomedical technologies used during surgeries including 3D printed bone guides, optical systems, and Doppler probes.  The patent had oral cancer with a tumor that invaded into the jaw which requited a partial mandibular resection. The plastics team used the patients fibula to create a new jaw and repair the oral defect after the resection.   Virtual surgical planning was used to model patient specific anatomy from CT scans of the fibular and facial features. The company 3D systems uses the patient specific data to create templates for cutting the fibula and mandible and to create the metal plates that hold the new mandible together. The surgical planning models the segments to cut the fibula into and it models them fit back together in the desired jaw shape with the metal brace. These models and surgical plan come with guides and templates so the bone can be cut in the right angle in the right place with aligned drill holes. To summarize: the mandible is cut at the predetermined modeled spots and removed, the Fibula is cut at specific spots into pieces that will fit together in the desired geometry to take the shape of the jaw, then the hardware designed to hold together the fibula pieces is installed to fix the new jaw to the surrounding bone.

Fibular isolation: The fibula needs to be removed and cut into 3 segments and then bent into the shape and contour of the jaw while maintaining contact between the segments. Incisions were made to isolate the fibula and its periostuim from the surrounding muscle while preserving the blood supply. I personally was surprised by the appearance of the bone surrounded by the periosteum and the thickness of the periosteum with all its vasculature.  The fibula was cut at both ends to separate out the middle section of bone. From the ends the periostum was peeled back  to reveal the bone but the middle section that would be used for the reconstruction was left untouched. This was an important distinction because for the bone to be healthy and heal in its new anatomic location, there needs to be a blood supply to each segment left intact. The proximal and distal ends of the fibula that interface with the knee and ankle were left in place with the cut ends left loose as if the middle section was still there.

Tumor and Jaw resection: The head and neck team removed the tumor and sent it off to pathology to check the margins. The pathology results indicated more needed to be removed so they excised more. The mandible cutting template was used to cut the bone and removed the section of jaw along with attached soft tissue.

Fibular reconstruction: The cut fibular pieces were placed in the metal plate guide and screwed into place. This piece with the attached vasculature was then it into the jaw and screwed into the remaining sections of the mandible.

Vascular microsurgery: To restore blood flow and increase the chance that the fibular flap would take, the vasculature of the periosteum was connected to the vasculature in the neck by hand sewn techniques of the use of a vascular coupling device. All of this work is done under a surgical microscope because the vessels can be 2mm in diameter. In brief, the vascular coupler can be fed two ends of a vessel and then it closes bringing the ends together and uses a junction to create a seal. The blood flow is critical to the patient outcome and the survival of the flap so it must be monitored every hour for the first day and then at longer time intervals for days after. To monitor the flow implantable doppler probes are used. They are made of a biodegradable cuff attached to the probe and the wire which exits through an incision. This is placed around the vessel during the surgery and allows for flow monitoring. If the flow stops more surgical intervention would be needed to salvage the flap. 

Resident Lecture

Monday morning I went to the resident lecture about skin cancer. Plastic surgeons see an abundance of skin and they commonly remove cancerous legions. This week's lecture was about non-melanoma skin cancer. Skin cancer is diagnosed more than any all other cancers combined and is an economic burden of over $8.1 billion. The most common kind is basal cell carcinoma followed by squamous cell carcinoma. Causes of skin cancer include chronic wounds, immunosupression, HPV, Inherited disease, melanogenesis, UV Radiation with UVA and UVB rays.  Different skin types confer different risks, a ranking of skin types is Fitzpatrick skin types that ranges from types I-VI and is how likely you are to burn. It was interesting to learn about cancer treatments for these diseases and the role plastic surgeons play.

Project update

I was able to isolate, freeze, and send 3 cell populations to my lab back in Ithaca. I stained and imaged samples of lean and obese tissue to use for an analysis of differences in the native tissue due to BMI. Preliminary results of my second decell method show promise in the technique even though there were some issue related to tissue processing and fixation that I learned from to make future iterations better.  

A big thanks to Dr. Spector for being a great mentor and giving me the opportunity to shadow in both the clinic and OR. I learned so much this summer and gained a much better appreciation of clinical practices, biomaterials, and tissue engineering products currently used. I had a great time working in the Laboratory of Bioregenerative Medicine and Surgery with helpful, fun, and smart labmates. I'm looking forward to continued collaboration with them in the future! 

Figure 1: H&E staining of breast adipose tissue

Week 7: Final Week in NYC

This week Dr. Brissette was gone so I spent the beginning of the week trying to run stats for my project. I also met with the biostatistics team at Weill Cornell and found out that the stats we were trying to run are a lot more complicated than I thought they would be and the biostatistics team is willing to help us and run the stats for us, which will help us out a lot. I also managed to get about 9 people for the project that I am doing with Dr. Starr that involves adding a sodium fluorescein drop to the eye and measuring the topography of it after time. From this study we hope to see whether or not there is a difference between the topography of the eye after fluorescein drops are added.

I cannot believe my time in NYC is coming to an end. I have had a great experience here and met so many incredible people both inside and outside of the hospital. I feel like I have been constantly busy for the last seven weeks since there is always something to do in the city. I will miss the fast paceness of the city and how much there is to do here. I ended up liking living in the city a lot more than what I thought I would and I hope to come back soon.

Week Seven: My Jaw Dropping Trip to the OR

My summer immersion term ended on a high this week with my first, second, and third trips to the operating room (as a medical personal rather than a patient, anyways) (Figure 1). Seeing surgery in person is weird experience, to say the least. Part of me was utterly in awe and wanted to see more and more but another part of me was feeling a little nauseous. All in all, my scientific curiosity won over and I had a great time, although I don’t plan on becoming a surgeon anytime soon. If you’re wondering what this has to do with my time spent in Infectious Diseases and my research: it doesn’t but my roommate, Brittany, and her clinicians Dr. Jason Spector, were nice enough to let me tag along. After all, who wouldn’t take the opportunity to see surgery if they got the chance?

Figure 1. Me all geared up for surgery outside the OR

The first surgery was a mandible reconstruction from a fibula free flap, basically reconstructing a jaw from the little bone in the patient’s leg. The fibula is a mostly unnecessary bone in the leg, so it’s like we are all walking around with our own spare parts. The surgery was simulated from scans of the patient’s body prior to surgery and a company, called 3D Systems Inc., used 3D printing to make cutting guides for the mandible and the fibula (Figure 2). The patient had a large tumor removed from his jaw and with it he lost part of his mandible and some of his teeth and tongue. I was shocked that anyone could survive with their calf entirely split down the middle and with their entire jaw opened. It made me inspired by the resilience of the human body. The surgery took 12 hours and I was there for 10 hours of it. It was incredible to see the finished product, a single, long, well stitched wound on the left calf and a relatively normal looking young face with a line of stitches from ear to ear with a little line through the chin and bottom lip. One of the coolest parts? This new chin (which included some muscle and even some skin from the leg) was able to receive blood from the rest of the face. Dr. Spector carefully isolated and attached individual veins from the cheek to the new chin, either sewing them together by hand or using a special device that pulls the two ends together and clips them with a tiny piece of plastic and metal. All of this was done under microscope since the surgical area was about two finger tips wide.

Figure 2. An example Virtual Surgical Plan (VSP). Figure adapted from VSP System Medical Modeling. Note this is not from the actual patient discussed in this post.

Surgery number two was a skin graft. The surgeons shaved a 200um thick square section of skin from the patient’s thigh and used it to cover a wound on the patient’s scalp, the location of a tumor that had been removed weeks prior. The skin was sewn in place over the hole in the scalp and then layered with bandages and cotton soaked in mineral oil. The thigh was dressed in a silicone sheet to help it heal but the wound itself was only deep enough to be comparable to a rug burn and should heal quickly and easily. This surgery took about 30 minutes.

Surgery number three was a scar and bed sore removable on a buttock. It was a simple procedure, largely cutting out the undesired areas, sending samples to pathology to check for infection, and sewing the wound up again. It took about one and a half hours. The weirdest part about this surgery for me was seeing what fat looks like inside the body. I have opted to spare you all a picture.

In addition to my time spent in surgery, I have been working on my data analysis and statistics. I have separated the participants into groups by level of cognition, frail, pre-frail, and non-frail, years since diagnosis with HIV, viral load, and number of immune cells. These groups are then compared to each other to see if they have statistically significant differences between them. So far, I have seen that low cognition (MOCA scores less than 26/30) is associated only with older age and higher frailty scores but not with any other factors such as body composition, weight, HIV viral load, or immune cell counts. I did not find any statistically significant differences in any factors for participants having HIV for 23 years or more. This is good news and may imply that HIV therapies are effective in the long term at maintaining body composition, immune system function, and HIV viral loads. Participants who were frail were older, had higher Body Mass Index (BMI), Fat Mass Index (FMI), fat mass, and lower skeletal muscle mass. While we may not be able to control age, we can encourage those who are HIV+ to be extra considerate of their diet and exercise. However, our study does not allow us to determine whether people are frail because of their higher fat compartment or if they have higher fat compartments because they were frail first.  

This is my last day and my last blog post. I will be leaving New York City tomorrow after one more stop at Broadway to see Aladdin. It has been an inspiring summer. Overall, I have learned 1) That I am glad I am not a doctor or surgeon, 2) I am very proud and excited to be in the medical field as a biomedical engineer, and 3) the areas of infectious disease and immunology are awesome, and I am glad to be a part of them. I am incredibly grateful for the experiences I have had in my life and I am humbled by the chance to give something back to the scientific community. My goal is and will continue to be to do quality research with the goal of bettering the health of many. Thank you so much to all the mentors, sponsors, friends, and family who have made this possible. Thank you for reading!