November 2015 • Vol. 4, Issue 4


MEMBERS MAKING NEWS

Editor’s note: Kimberly was invited to describe the MR Technologists Challenges from a Nuclear Medicine Technologists point of view at the 2014 ISMRM / SMRT Joint Forum in Milan, Italy. Her professionalism and knowledge in the emerging field of PET/MR made her a Member Making News! Read about Kimberly’s journey into the hybrid imaging combining technologies.

Kimberly Jackson, BS, CNMT

As we all reach that final stage of college, we try to finalize what our career path will be for the next step in our lives. We wonder if all we’ve worked for and accomplished up until that moment is leading us to where and who we want to be in life. My aim was always to help others and to be a part of a growing medical field, I just did not know exactly how. While on a tour at New York University (NYU) Medical Center, I was able to observe the Nuclear Medicine department and I instantly became intrigued. How spectacular medicine can be to have the capability to use a radiopharmaceutical to see the diagnosis or progression of a patient’s illness. I have been a part of the Nuclear Medicine family at NYU for 5 years with each day offering more opportunities to learn more.

After being trained in general Nuclear Medicine procedures such as Bone, Lung VQ, Hepatobiliary scans and more, I moved on to positron emission tomography (PET). PET/CT opened the door to new radionuclides and new research opportunities. I have always had an interest in nuclear medicine research which led me to apply for a job in PET/MR as the Lead Nuclear Medicine technologist. This was a new department and an upcoming field for Nuclear Medicine and MRI.

The field of nuclear medicine, specifically PET, has undergone drastic growth since its introduction in the 70’s and I have had the privilege of seeing some of the growths that this field has to offer. A nuclear medicine exam involves injecting, inhaling or swallowing a radioactive compound, generally termed “radiotracer”. This radiotracer will map a physiological or biochemical process, ultimately localizing in the targeted area being studied. The gamma rays emitted from the radiotracer are detected by the scanner to generate the images. Unlike most other imaging types, such as X-ray, nuclear medicine imaging can show how different parts of the body are working and possibly detect problems from a much earlier time-point.

In PET imaging, the most commonly utilized radiotracer is fluorodeoxyglucose (18F-FDG). FDG is a glucose analog, meaning it behaves similarly to glucose being actively taken up in areas of high metabolism, but becomes trapped in these high metabolic areas instead of continuing on in the pathway for energy production. Because cancer cells tend to be very metabolically active these scans can provide radiologists with information such as how far cancer has metastasized and how well treatment may or may not be working for the patient. In general, nuclear medicine procedures provide functional information in conjunction with other modalities such as MRI and CT which offer anatomical information. MRI, providing superior soft tissue contrast to CT has the added benefit of not utilizing ionizing radiation to generate images and therefore does not increase the radiation exposure to the patient. While nuclear medicine does provide minimal ionizing radiation exposure; the benefits out-weigh the risks. In order to better understand the capabilities of both modalities further, I needed to educate myself on every aspect of the two fields.

Before working in MRI, I only knew the definition of the acronym, magnetic resonance imaging (MRI). I received MRI safety training from NYU but I felt I wanted to learn more in order to understand my job more and become a better technologist. With the support of my department, I attended and completed a 3 month course in MRI which enabled me to understand the terminology, parameters and workflow better.

As a Nuclear Medicine Technologist, being at the forefront of a new hybrid field, with multi-million dollar equipment is astounding. At NYU, we have the Siemens Biograph mMR™ camera, where we have performed both research and clinical PET/MR and MRI studies. Since the first simultaneous PET/MR scan was performed at NYU in July 2012, the volume has exceeded far over 1,000 scans. We obtained ICAL accreditation for PET in oncology and neurology and ACR accreditation for MRI. We acknowledged that attempting to merge two departments that function very differently in terms of workflow and structure would be one of the major challenges. Involved in this challenge is the integration of Nuclear and MRI Radiologists to work as one in reading and reporting on the simultaneous PET/MR exams. Discussions also focused on how to integrate and cross-train nuclear medicine technologists and MRI technologists into one department.

For an MRI technologist, one of the main focus for day to day operations has always centered on the fact that the magnet is always on and never had to think about time, distance and shielding among reducing exposure from a patient or a possible contaminated area. Such terms as a “hotlab”, where radioactive material is kept, was new to the MRI technologists I was now working in close proximity. Similarly, as a nuclear medicine technologist having the simple concern of having a few credit cards and my phone not be able to possibly operate because I forgot and brought them into the scan room. To now knowing that it could cost a person’s life if I do not screen patients properly for such unsafe metal implants as a pacemaker or enter the scan room with a magnetic projectile such as a scissors.

There was more terminology to exchange between the two departments. These were all challenging in the beginning but with shared knowledge and educating ourselves continuously, we have been able to maintain a safe environment for all. The billing, exam labelling and scheduling were aspects that required additional time to finalize. We needed to answer the question of what more does a PET/MR scan offer that a PET/CT or MRI only scan could not offer patients.

Furthermore, incorporating MRI sequences within the PET bed acquisitions for a whole body scan increases the scan lengths from approximately 30 – 45 mins with PET/CT to approximately 60 – 90 mins. PET and MR data are acquired simultaneously which can improve the accuracy of lesion assessment. In the beginning of this proposed new department, all studies were research, but after several discussions and breakthroughs, we now provide clinical PET/MR scans in oncology and neurology. Our institution routinely performs clinical PET/MR scans on patients with lung, liver, prostate, and breast cancer. Additionally, we perform regular neurology scans of patients with epilepsy, dementia, and brain tumors. We provide clinical care to patients of all ages and the priority, as it should be for all facilities, is the patient’s comfort.

The departmental workflow involves providing advanced patient prep instructions to each patient 2 – 3 days before their exams. MRI safety screening forms along with other medical history questionnaires are provided to the patient. Every step of the procedure is explained to the patient before commencement of the imaging. An MRI image is obtained when radio-frequency waves are transmitted and a signal is received through a conductor, called a coil, to generate the images for the scan. Some of these coils are labeled “mMR”, which is to be used when performing simultaneous PET/MR imaging only but all coils can be used for MRI imaging. The mMR-labeled coils to be used for simultaneous PET/MR imaging have an attenuation correction map already calculated and taken into account. There are some coils used for only MRI scans, such as the knee and shoulder coils which are not used for PET/MR acquisitions because they cause more attenuation, noise in the image due to the thickness of the material in the coil.

At the beginning of each scan, a scout/ localizer for location of the area to be imaged is performed as in any general MRI exam. MR-based attenuation correction (MRAC) Dixon scan is then obtained which separates soft tissue, adipose fat, air and water. For body cases in which the chest, abdomen and pelvis are scanned, a breath-hold MRAC scan lasting approximately 19secs is obtained and the remainder of the scan is all free-breathing. These areas of the body are high risk for motion and can cause blurry images. A lot of the training for working in PET/MR comes from being in the field and learning new information each day. This is how we grow as technologists, sharing and learning new ideas.

In conclusion, being a nuclear medicine technologist has opened the doors to so many advantages such as learning and growth in a field that I love and a career that I am passionate about. Working in the PET/MR field has allowed me to learn two different modalities and see their merger first hand. Safety is always a concern for patients, colleagues and myself when working in a magnetic field, and also when dealing with radiation exposure. Nuclear Medicine is a field that is always growing and offering new possibilities. It has been thus far amazing with new developments in how we diagnosed and treat cancers among other conditions. In the PET/MR field, more referring physicians are changing their source of care to PET/MR instead of having patients do PET/CT and go for a MRI exam separately. For referrers who focus mainly on pediatric care, the removal of additional exposure caused by CT or x-rays is an obvious change of care for their patients. The exams may be lengthy but can be reduced to what is performed routinely for an MRI exam. Simultaneous PET/MR imaging has numerous challenges but with the volume of patients growing each day and new breakthroughs being made with its advancements, there are no limits to where this new modality can go and similarly, there are no limits for the Nuclear Medicine technologist that always wants to learn more.

References: Recent Developments in Nuclear Medicine for Cancer Management: From Nuclear Medicine to Molecular Imaging Townsend, D.W., Dual-modality imaging: combining anatomy and function, J Nuclear Med. (2008) 938 – 955
 

Signals is a publication produced four times per calendar year by the International Society for Magnetic Resonance in Medicine for the benefit of the SMRT membership and those individuals and organizations that support the educational programs and professional advancement of the SMRT and its members. The newsletter is the compilation of editor, Julie Strandt-Peay, BSM, RT (R)(MR) FSMRT, the leadership of the SMRT and the staff in the ISMRM Central Office with contributions from members and invited participants.