SIR Medical Student Research Spotlight Interview Research Series:

Dustin Roberts, UCLA David Geffen School of Medicine, 2019

Interviewed by: Mahati Mokkarala, Washington University School of Medicine, 2019


Can you tell me a little bit more about your research – What exactly are you working on?

Thanks, I appreciate the opportunity to interview today. My current research interest lies in the minimally invasive treatment of pulmonary arteriovenous malformations (AVMs) in patients with Hereditary Hemorrhagic Telangiectasia (HHT) – also known as Osler-Weber-Rendu syndrome – a genetically inherited autosomal dominant disorder that involves abnormal vascular development. My institution is one of the HHT Centers of Excellence, so we get lots of referrals and a unique opportunity to perform a large number of pulmonary AVM embolizations. I am currently working on a clinical research project analyzing reperfusion rates after embolization. We are interested in understanding the factors that contribute to AVM reperfusion and what we can do to improve upon our technique in order to achieve a more sustainable result. Some of the parameters I am investing include methods of re-embolization (such as proximal vs. distal, coils vs. plugs, etc.), routes of reperfusion (such as through vs. around the embolic), and success rates with respect to the type and number of coils or other embolic materials used. I am currently generating results for our single-center retrospective study comprising a 10-year cumulative dataset. My primary task for this project is similar to that of any other clinical research – lots of chart review, data collection, and statistical analysis. It’s an especially great project as a medical student because I am able to do much of the work from home and at odd hours of the night. A typical research day for me involves logging into the EMR from home, pulling up operative reports, fluoroscopic data, and patient charts, then extracting all pertinent data and incorporating it into a master spreadsheet for analysis. At my medical center, we obtain chest CT or MR with contrast 1-3 months post treatment to determine success rates, looking for any evidence of patent flow beyond the embolics to suggest AVM recurrence.

Fig. 1 – Photo of UCLA’s HHT Center of Excellence at Ronald Reagan Medical Center.

Why is your research important for the interventional radiology field? Can you describe your research in the context of the current field?

HHT is actually quite common as far as rare genetic disorders go. The prevalence is said to be as high as 1 in 5,000 in the United States, and there are people who have this disease and don’t even know about it. The clinical criteria to diagnose HHT, known as the “Curacao criteria”, is comprised of 4 different components: recurrent epistasis, telangiectasias (most commonly the oral mucosa, hands, or ears), one or more visceral AVMs (most commonly the lungs, brain, or intestines), and a positive first-degree family history. 3 of 4 of these criteria will buy patients a definitive diagnosis of HHT; 2 of 4 is probable. Many of these patients will present as young adults complaining of shortness of breath, fatigue, or bloody noses. Eventually, diagnostic work up leads to a chest CT that reveals pulmonary AVMs, and they land right in IR clinic for primary management. Patients will also often work closely with neurosurgery or neuro IR for any cerebral AVMs, and ENT for management of epistaxis. These patients frequently have recurrent gushing nosebleeds that affect their quality of life. When they finally arrive to IR clinic, it is revealed that half of their family members have a similar story, and they end up in clinic too. So it becomes something of an IR family practice. Clinicians may decide to get genetic testing done as well to risk stratify patients, especially for family planning. Around 90% of the time, patients are positive for a mutation in either endoglin (Type I HHT) or activin receptor-like kinase (Type II HHT). IR really has its place in this field as there are very few options for treating pulmonary AVMs outside of embolization. Having pulmonary AVMs significantly increases the likelihood of stroke and brain abscess – the risk is 10% per year if untreated. Hemorrhage and hypoxia are of course other complications. IR is leading the way in the clinical management of patients with HHT. Historically, before IR had a role, these patients needed a thoracotomy to resect AVMs. Now, we just approach them endovascularly, lay a couple of coils or plugs down, and the patient is out of the hospital within 24 hours.


Fig. 2 – Superselective microcatheterization and coil embolization of a simple right middle lobe pulmonary AVM.

Fig. 3 – Right pulmonary angiogram showing two complex right upper lobe AVMs pre- and post-embolization in a patient with HHT and recent history of embolic stroke.

What are some next steps for your research? What do you hope to accomplish during the year?

Just recently, we’ve completed a preliminary project looking at all AVMs that have required repeat embolization and submitted a manuscript to JVIR. In a true retrospective fashion, we are now focusing on all native AVMs to glean information about the initial intervention and compare to re-embolization. There are lot of patients to look at and more chart review to do, but I am excited to see what results we find. This study will be one of the bigger pulmonary AVM embolization studies out there in the literature; hopefully we’ll get people thinking about the way in which we are currently managing our HHT patient population and how we can improve their care.


What is the most challenging part of research at your stage of training? What skills do you think medical students should have if they want to be successful in research?

That’s a tough question. I think that really IR is a small field that students usually don’t get much exposure to until later on in medical school. In general, research as a medical student is hard to get involved in. Medical students are certainly no expert or sub-specialist yet, and IR is quite sub-specialized. It can be overwhelming since IRs tend to have sub-specialist knowledge from head to toe, across multiple organ systems and disease processes. Rule number one: you have to own the disease you’re interested in studying. After shadowing and rotating a bit, I got to know the literature by reading some of the landmark studies and looking into previous articles on what has been done historically for pulmonary AVM treatment. I also focused on getting to know the clinical context by going to outpatient clinics and getting into the angio suite to see what goes on first-hand. I think it is valuable to learn how to speak the language of IR; knowing all the catheters, wires and common tools used to treat patients, as well as the diagnostic lingo and conventional language used to describe anatomy. I think the biggest challenge when getting involved with research as a medical student involves getting used to the nuances of the field. Once that steep learning curve is conquered, everything is smooth sailing from there, and research becomes a much more feasible endeavor.



What are your thoughts on medical school involvement in research? How will medical school involvement push the IR field forward?

Medical school involvement in research is paramount. In terms of a strong CV and candidacy for residency, it speaks very highly, especially if the student gets first author publications. Research involvement shows dedication to academic medicine and to the particular field they are interested in. IR faculty can be very busy so it can be hard to get involved in research right off the bat. After rotating through the hospital, however, students get to know the attendings and residents, the electronic medical record, and learn the basics of chart review – a foundational principle of much of clinical research.

Also, medical students can spread the word of IR on other rotations. This is purely anecdotal, but I was on my OB/Gyn rotation and one of our patients had significant fibroid symptoms and had undergone multiple myomectomies. Her prior doctor had told her that her only option was a total hysterectomy. Understandably, she was adamant against a hysterectomy. I brought up the possibility of and cited the efficacy for uterine fibroid embolization (UFE) and high-intensity focused ultrasound (HIFU) to my attending, who wanted to learn more. The patient had never heard about these options before and the attending hadn’t even thought to go that route. We ended up referring her out to IR for further management. The patient’s reaction to knowing she had other options alone was enough for me to realize that IR and minimally invasive therapies are the future of medicine.


What are some tips for medical students interested in IR?

I would recommend that students get involved early on, or as early as possible, including shadowing and trying to do a rotation in IR even if it’s not offered at their institution – I think taking the reins and bringing up to school administrators the idea of integrating IR into third year is a great idea. Also, joining the school’s IRIG or starting one if one doesn’t exist already can be huge on the CV as it shows interest in a leadership role. An IRIG is the perfect opportunity for students to interact with multiple IR attendings, find a mentor, and get involved in a research project.