Several applications exist for a whole brain positron-emission tomography (PET) brain imager designed as a portable unit that can be worn on a patient’s head. Enabled by improvements in detector technology, a lightweight, high performance device would allow PET brain imaging in different environments and during behavioral tasks. Such a wearable system that allows the subjects to move their heads and walk—the Ambulatory Microdose PET (AM-PET)—is currently under development. This imager will be helpful for testing subjects performing selected activities such as gestures, virtual reality activities and walking. The need for this type of lightweight mobile device has led to the construction of a proof of concept portable head-worn unit that uses twelve silicon photomultiplier (SiPM) PET module sensors built into a small ring which fits around the head. This paper is focused on the engineering design of mechanical support aspects of the AM-PET project, both of the current device as well as of the coming next-generation devices. The goal of this work is to optimize design of the scanner and its mechanics to improve comfort for the subject by reducing the effect of weight, and to enable diversification of its applications amongst different research activities.

Abstract-

Society has, as one of its base survival techniques, the reinforced training and education of its participants, beginning at an early age.  In order to manifest value to its citizenry, it acts to foster the necessary social and economic skills to maintain the current status quo.  Unfortunately, this has resulted in a reliance on complacency, leading to a more reactive, rather than proactive, culture.  In order to break society of this contentment a more proactive mode of operation will require a more individualized approach in developing specialized skills, such as leadership, within its population.  Leadership, a basic survival instinct in men and women, has the potential to provide individuals with the proactive capability to solve problems more effectively and to anticipate the future needs of the societies they guide.  This paper addresses these issues and provides an example of a practice routine for improving the leadership capabilities of our youth.

Ambulatory Micro-dose Positron Emission Tomography (AM-PET) is a portable PET brain scanner that does not require patients to remain still but allows them to move as they regularly would over the course of the scan (i.e. clapping hands, walking in place, and other stationary movements). Traditional PET scanners require patients to remain still for an extended duration in a small confined cavity. This is problematic for those who have conditions such as Parkinson's and Autism; in many cases, they must be sedated before the test can be performed. West Virginia University's AM-PET Helmet allows for these regular human movements to be made. It also allows researchers to see parts of the brain where traditional PET scanners cannot due to the limited mobility of the device. A proof-of-concept AM-PET helmet has been developed and tested on patients. This prototype uses 12 photodetector modules placed in a single circular ring around the subject's head, each sensor weighs ~200 grams with an overall ring weight of ~3 kilograms. This prototype system was developed by researchers at West Virginia University's Health Science Center (HSC) and has been tested successfully. The next generation helmet, currently being developed, will allow for improved images with additional sensor rings to increase brain coverage. The next generation AM-PET helmet is projected to weigh ~10 kilograms. This represents a potential challenge for long time usage and various safety concerns for the patient. Currently, a support system with a counterbalancer is used to reduce the weight off the patient. This counterbalancer assists in alleviating vertical weight off the patient. Patient safety is always a primary concern; therefore the helmet must be tested thoroughly to ensure safety of the patient at all times, especially when rotating ones' head; conceivably many potential patients are frail (i.e., from disease or age). This report describes testing of the system on healthy individuals with the use of an electromyography (EMG) and a Vicon system to explore neck muscle activity and head movements and to determine "safe use" parameters, mechanics and impact of head mounted weight on patients and mechanical support structure. iii ACKNOWLEDGMENTS I would like to pay special thankfulness, warmth and appreciation to the persons below who made my research successful and assisted me at every point to cherish my goal: My advisor, and co-chairman, Dr. Thorsten Wuest for his vital support and assistance throughout my thesis and graduate school. His encouragement made it possible to achieve this goal. My co-chairman, Dr. Xiaopeng Ning, whose knowledge and lab equipment helped create credible research results. Professor Julie Brefczynski-Lewis, Head of the AM-PET project, whose excitement always kept me encouraged and motivated. All the faculty and staff in the Industrial Engineering department at West Virginia University and the participants who took time out of their day to help achieve my goal.

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