Cerebrovascular and Stroke Imaging
Imaging of acute ischemic stroke has been a pillar of research for the Seaman Family Centre since its inception in 1999. Nearly forty thousand Canadians are afflicted by stroke each year, often requiring long term care and rehabilitation – a strain on families, the health care system and our economy. The Calgary Stroke Program, the HBI Dementia and Congnitive Disorders neuroteam and the Centre have targeted MR imaging as it correlates with clinical signs and symptoms, CT imaging, and transcranial Doppler findings. By advancing MR imaging techniques, we aim to better understand early ischemic stroke pathophysiology to develop strategic treatment strategies.. The location of the Seaman Family Centre adjacent to the Emergency Department of Foothills Medical Centre has afforded the Centre enviable access to patients, allowing world-leading rapid imaging of acute stroke. More recently, focus has expanded to also include imaging of transient ischemic attack and minor stroke, as well as small vessel disease leading to cognitive loss.
Epilepsy is one of the most common and serious neurological conditions, affecting up to 300,000 individuals in Canada alone. Nearly 30% of these patients have seizures that cannot be controlled by any available therapy and many of the remaining patients have intolerable medication side effects or complications of therapy. The Epilepsy Imaging Research Program, in collaboration with the Seaman Centre, investigates how seizures are generated and can be predicted, in order to better treat and prevent these debilitating events. The research program design complements and enhances our clinical Calgary Comprehensive Epilepsy Program. Using novel imaging and EEG approaches, examination of the origin and propagation of focal seizures within the brain are proving to supply new insight and transformative clinical impact., Epilepsy research at the Center has generated new clinical language fMRI and T2 relaxometry imaging protocols, which are routinely employed to guide clinical decisions.
Functional MR Imaging
Interpretation of clinical functional MR imaging (fMRI) results is strongly dependent on the task patients are asked to perform while in the MR scanner and the effort they expend to perform those tasks. Many subjects are too ill, too fatigued, or too immobile to be able to perform tasks well, thereby limiting the clinical research applications of fMRI. Research in the Seaman Family Centre’s fMRI program is focused on finding ways to study the synchrony between brain regions while the patient is at rest (that is, in the absence of tasks) as means to assess the integrity of brain networks in the presence of neurological disease. The primary goal of this effort is to advance resting-state fMRI as a biomarker of disease diagnosis, prognosis, and treatment efficacy. In addition, we also perform traditional task-based fMRI experiments. The HBI-supported Neuroimaging Research Unit (NIRU) ensures that these new approaches are translated to the study of stroke, epilepsy and mental health disorders.
Mental Health Imaging
Mental disorders like depression and schizophrenia are among the leading causes of disability worldwide. Approximately 20% of Canadians will experience a mental illness in their lifetime. Despite considerable progress in pharmacological treatments, our understanding of etiology and biological mechanisms of mental disorders remains limited. Existing treatments for mental disorders are only partly effective and there is no physical diagnostic test to objectively confirm the diagnosis of mental disorders which are subjectively based on behavioral criteria. Neuroimaging methods provide an opportunity for studying the brain mechanisms that underlie illness development, progression, treatment responsiveness and clinical recovery. Using structural and functional brain imaging technologies, researchers in our centre are currently involved in studying the fundamental neural mechanisms that are disrupted by psychosis and depression. Much of this effort is in conjunction with members of the Mathison Centre for Mental Health Research & Education.
Multiple Sclerosis Imaging
Multiple sclerosis (MS) is a common but severe central nervous system disorder that primarily affects young adults in the prime of their lives. In Canada, there are over 100,000 people living with MS, more than any other country in the world, costing us nearly one billion dollars annually. There is no cure. MR imaging of MS has become an important tool for the diagnosis and management of the disease. Research at the Centre using the high field 3T scanner has been comprehensive in scope, ranging from natural history studies, to patient–control comparisons, to participation in full-scale clinical trials, all aimed at gaining a better understand the mechanisms of MS. This knowledge can then be used to develop novel outcome measures and form models of disease to evaluate repair; and to assess the impact of candidate interventions on MR imaging outcomes. These promising studies should accelerate the discovery of new therapies for MS. Our MS imaging efforts occur in collaboration with the HBI's MS Neuroteam.
Development of a novel mobile MR scanner capable of pre-, intra- and post-surgical imaging within the surgical environment as been one of the hallmark achievements of the Seaman Family MR Research Centre. The system was developed in collaboration with the National Research Council Institute in Winnipeg, MB and Magnex Scientific UK of Oxford, UK and is now employed in multiple academic hospitals worldwide. The innovative system consists of a ceiling-mounted moveable MR scanner that can travel in and out of a neurosurgical operating room in less than thirty seconds. The custom operating table is constructed from titanium, hydraulically mounted and completely compatible with the high magnetic field, as are all of the surgical tools and equipment in the operating room. Initially the system consisted of a suspended 1.5 T scanner. In 2009, the surgical suite was renovated and the magnet was replaced by a wide-bore (70 cm) 3T scanner. The intra-operative program has augmented >1,500 neurosurgical cases since 1998. Many studies of the value of intra-operative imaging have proven the clinical benefit and efficiency of neurosurgical procedures when quality-assurance scans can be acquired during surgery, helping to ensure complete tumor removal.
Following on the strength of the Centre’s innovation in the development of intra-operative MR imaging, a program for the development of a state-of-the-art neurosurgical robotics was born. Project neuroarm began from an idea: How can we make surgery safer? What will it take to create an optimal outcome for every surgical patient? neuroArm was designed to be meet these challenges by taking full advantage of the blended MR imaging neurosurgical environment. Completely MR compatible, the robot can perform procedures outside or inside the bore of an MR scanner. It includes two remote, detachable manipulators on a mobile base which can be removed and mounted on the titanium surgical table of intra-bore stereotactic procedures. The end-effectors interface with surgical tools which are based on standard neurosurgical instruments. The robot is manipulated in a slave and master configuration, controlled at a workstation in an adjacent room that is equipped with enhanced sensory outputs to recreate the surgeon’s experience remotely. The robot has now performed surgery on more than 100 patients and counting.
The Musculoskeletal Imaging program at the Seaman Family Centre and the McCaig Institute for Bone and Joint Heath examines the biomechanics of the knee. Sophisticated MR-compatible devices have been constructed to image the knee in various loaded states. Both static and kinematic imaging is used to determine forces on various structures and this knowledge is used to enhance studies. These studies provide important information about joint biomechanics and when used with other imaging approaches, is used to drive complex three-dimensional models of knee function.
Vascular and Cardiovascular Imaging
The application of MR imaging to the study of blood vessels requires specialized tools and expertise. At the Seaman Family tools we have this expertise and a record of developing new tools and applying them to unique patient groups. Imaging of the carotid artery, given its role in acute stroke, is an area of specific interest. Work has explored the role of contrast-enhanced and non-contrast techniques in head, neck and body angiography, as well as new methods for characterizing carotid wall plaque. Some projects involve collaborations with the Calgary Stroke Program and the Libin Cardiovascular Institute of Alberta.
Much effort is spent at the Seaman Family Centre acquiring information on normal human subjects. We are interested in characterizing quantitative imaging techniques that explore factors like tissue relaxation, iron loading, perfusion and anatomy in the brain over the lifespan (18 to 89 years of age). This information provide us critical details about how the brain ages, as well as a rich data set to compare against our patient populations (described above). To date we have entered over 250 subjects into the normative study and are about to embark on asking a subset to return for follow-up imaging 2 years after the initial scans. This new data will allow us to see how these data change over time at different life stages.