An Academic Life in Imaging: Teaching, Insight and Research

Transcription

1 An Academic Life in Imaging: Teaching, Insight and Research E. Mark Haacke, PhD, President, Magnetic Resonance Innovations, Inc. Director, MR Research Facility, Wayne State University Detroit, Michigan

2 YOUR MISSION, IF YOU SHOULD DECIDE TO ACCEPT IT,

3 IS TO BOLDLY GO WHERE NO MAN HAS GONE BEFORE

4 Magnetic Resonance PIONEERS By 1946 Bloch and Purcell and co-workers captured the the behavior of an atom with a non-zero magnetic moment (like the proton, for example) situated in a magnetic field. (Nobel Prize in Physics in 1952.) Their contributions to the field from these first papers was precocious and even 70 years later their work carries modern significance. Although quantum physics was needed to formulate the experimental and theoretical results, the final impact rests on the very simple relationship given by the Larmor equation relating the frequency of rotation or precession frequency ( ) and the local magnetic field (B) via B.

5 Visualizing Quantum Mechanics Lauterbur Thin slice T1 and T2 weighted 3D images of the brain. Nobel prize in Medicine or Physiology Mansfield

6 1 An Academic Life in Imaging: Teaching, Insight and Research E. MARK HAACKE, PHD PRESIDENT, MAGNETIC RESONANCE INNOVATIONS, INC. DIRECTOR, MR RESEARCH FACILITY, WAYNE STATE UNIVERSITY DETROIT, MICHIGAN HOW LUCKY TO ENJOY ONE S JOB AS PART OF EVERYDAY LIFE.

7 Education 2 Take good students under your wing and help guide and nurture precocious students at an early age. Prof. John Moffat was my advisor and mentor. Summertime provided me the opportunity to teach (statistics/math) and earn some money.

8 Education 3 Clear lectures, get the main points across Use examples that demonstrate the key principles Promote students to ask questions Get students to work together to attack problems Sit with groups of 5 or 6 and review in detail a problem Get the students to present at the blackboard Once a principle is learned it will never be forgotten

9 Education and early collaborations 4 Have more senior students help tutor new students Have regular informal lectures at the blackboard Have monthly meetings giving an overview of research Create a team environment early; have weekly journal club meetings Engage them outside work on occasion with sports or outings Have office hours, be accessible (Ramesh)

10 Closing thoughts on education 5 It s easy to show that Create a text that carries the student step by step through the basic to advanced concepts without once using that phrase! The result of this 28 man-year effort was The Green Bible of MRI.

11 Collaborations and team science 6 Offers new scientific and cultural experiences Increases your group s knowledge Provides more data and much faster! Neusoft MR laboratory, Shenyang, China East China Normal University, Shanghai, China with the physics group of Prof. Yang Guang.

12 When it comes to research: be determined 7 Research does not always come with the infamous AHA but often follows the adage: 10% inspiration and 90% perspiration This applies to: abstracts (rf) papers (MRA) grants (mannitol)

13 Susceptibility Weighted Imaging 8 SWI Enhances the presence of ferritin, hemosiderin and deoxyhemoglobin. Exquisite images from which brain damage, microbleeding and increases in deoxyhemoglobin can be diagnosed. One President mused: Beautiful but what s it good for? Haacke EM et al. Susceptibility weighted imaging. MRM, 52: 612; Wizard of Id

14 Scientific Creativity 9 Ideas take time to gestate and mature and become useful like SWI Everyone has a different perspective. Think out of the box (Zhipei). Advisors have to be open and flexible to new ideas. Reviewers need to have the insight as to not only the fact that these new ideas have potential but that a group s history is key to their future success and not to get stuck on minutia. Advisor Student Reviewer

15 Eye anatomy / Our MRI Image 10 Human Retina, Jan , Courtesy of Yongsheng Chen

16 7T SWI 215µ x 215µ x 1000µ TE = 16ms; TR = 45ms FA = 25 ; 8 slice mip 15 minute scan Imagine brain functional imaging (fmri) at this resolution! 11 Image courtesy of Yulin Ge, NYU 3T SWI 200µ x 400µ x 1000µ TE = 15ms; TR = 30ms FA = 12 ; 4 slice mip 9 minute scan

17 The Dream of MR angiography μ x 250μ x 500μ Small arteries around 250μ are now visible. Ahhh, at last, high resolution MRA! Or is it? Close but no cigar! It takes far too long to be useful clinically and still fails to show 50μ vessels. SWI is so beautiful, showing veins down to 50μ to 100μ. How can we make arteries look like veins to get the same quality MRA as we do with SWI? AHA!! Modify the susceptibility of the arteries!!

18 MICRO Microvascular In-vivo Contrast Revealed Origins 13 MICRO imaging: 50μx200μ in 15 min Using the iron based USPIO agent called Ferumoxytol.

19 Comparison of MRAV using SWI and cadaver brain dye injection. b 14 c d a) Georges Salamon s image of arteries in the human brain. b,c,d) Data from TE = 8ms with 0.1mm x 0.2mm x 1.25mm at 7T. b) MRA pre-contrast, c) mip post-contrast SWI for 4mg ferumoxytol and d) mip pre-contrast. Note that c) is a mixture of arteries and veins. However, the thalamic arteries are clearly highlighted in the post-contrast image. Image d) can be used as a guide as to where the veins are since it is a pre-contrast SWI.

20 Ferumoxytol enhanced MRAV 15 A Image courtesy of Yulin Ge and NYU.

21 Future Directions Imaging materials Creating an image for something that itself has no signal, possible or impossible? Distortion free fmri The perfect PhD demonstrating that we can create an image with no signal that has value!!! Until that is you begin thinking, when the light bulb comes on and the function of the brain comes to life. Micro magnets Creating an imaging system with unheard of gradient strengths and possibly enhancing signal in cells by a factor of 1000 or more. 16

22 The Anatomy Lesson of Dr. Nicolaes Tulp: Rembrandt 1632 Until very recently we had to cut the body open from the outside, now we have inverted the problem and we can view the body from the inside out! 17

23 Strategically Acquired Gradient Echo (STAGE) Imaging 18 Chen, Yongsheng PhD student WSU, Detroit, USA Wang, Yu MS student ECNU, Shanghai, China

24 Strategically Acquired Gradient Echo (STAGE) Imaging: Complete 3D coverage of the brain in 5 min. 19

25 T1 Weighted Images 20 A B C Richard Ernst, Nobel Prize in Chemistry 1991 A: T1 MP RAGE, the reference T1W; B: T1W from 1 st echo of B2; C: STAGE Enhanced T1W from B1 and B2.

26 Presenting the first visualization of the fetal venous anatomy of the brain using SWI 21 Pilot scan on the left, effective transverse SWI on the right: 37 weeks 1 day

27 22 GA 37 weeks Fetus Placenta

28 23 Non contrast enhanced MR angiography images of the heart and the major vessels in human fetus. scale ~ 4 mm

29 T1 T2 Venous Thrombosis: before treatment and after thrombolysis 24 Guangbin Wang M.D. Shandong Medical Imaging Research Institute PRE POST

30 Sturge Weber Syndrome 25 3D-T1 Post Gd 3D T1 SWI (no contrast agent) Czabo Juhasz, Yang Xuan and Dr. E. Haacke, Wayne State University

31 Motorcycle trauma: medullary vein involvement 26 SWI T1 PCn

32 The First Clinical Applications of SWIM in Traumatic Brain Injury (TBI) 27 SWI minip image projected over 16mm Corresponding MaxIP susceptibility map image projected over 16mm Cerebral Microbleeds: Pathophysiology to Clinical Practice (Cambridge Medicine) Editor, David J. Werring, 2011, ISBN-13:

33 Normal volunteer 28 Iterative SWIM single slice SWIM single slice with boundaries MIP Iterative SWIM over 4 slices Iterative SWIM single slice SWIM single slice with boundaries MIP Iterative SWIM over 4 slices

34 Substantia Nigra (SN) Region II Iron content in PD and Controls from SWIM The plots show region II (high iron region) content plotted as a function of age for 15 PD (red) and 174 controls 1 (green) for right (upper) and left (lower) SN. Right substantia nigra 29 Left substantia nigra The regression line for the PD group shows a higher slope which may indicate an increased rate of deposition from the onset. 1. Liu M, Liu S, Ghassaban K, Zheng W, Dicicco D, Miao Y, et al. Assessing global and regional iron content in deep gray matter as a function of age using susceptibility mapping. J Magn Reson Imaging Jul;44(1):59-71.

35 Contrast Enhanced Tumor Imaging 3D T 1 weighted 30 Flash 3D T 1 weighted pre- Gadolinium series Flash 3D T 1 weighted post- Gadolinium series T 1 subtraction maximum intensity projection image Tumor draining/feedin g vessels The 3D sequence allows better coverage of the tumor volume and pre-post contrast imaging allows exact subtraction revealing enhanced regions and in some cases even feeding/draining vessels.

36 Using caffeine decreases blood flow to the brain 31 two cups of coffee and you will have a major change of blood flow to the brain maybe we should approach Starbucks for funding at least it is a relatively harmless contrast agent to use to study the brain and a heck of a lot cheaper

37 SWI as a high resolution BOLD imaging method SWI PRE CAFFEINE SWI POST CAFFEINE 32 MinIP of caffeine/gd over 28 slices with 4 phase multiplications

38 Imaging veins and blood products using SWI and SWIM: Challenging the neurovascular system mg caffeine pills (a, d) or 1000mg diamox IV injection (c, f). Compared to the control condition (b,e), significant oxygen saturation changes are observed postchallenge on veins throughout the brain. SWI SWIM Caffeine: flow change = 27% ± 9% and ΔY = 0.09 ± 0.02 Diamox: flow change = +40% ± 7% and ΔY = ± 0.01

39 Two scans from same stroke patient MRI scan date: MTT 34 SWI MTT SWI MRI scan date:

40 Cerebral amyloid angiopathy 35 50µ objects can manifest as 1mm 3 objects

41 Time to go sailing 36 Black dots count No of counts /29/03 2-5/27/04 3-6/9/05 4-3/2/06 Scan no

42 Informational Websites 37 Clinical applications of SWI and SWIM See The role of abnormal venous flow in neurodegenerative diseases: MS as an example See Our work in Detroit at Wayne State University See Business website See

43 Communication 38 Communication oral: Talking, yelling, fire/light, land line phones, cell phones, skype on computers Data storage: Stone, sheepskin, paper, floppy disks, CDs, DVDs, thumb drives, cloud storage Communication written: Hand written, typed letters, books, fax, optic cables for file transfer, computer word files, internet transfer Math and Science: Mental calculations, abacus, calculator, computer The future: All of the above integrated into a single entity = BCI

44 Brain Computer Interfacing (BCI) and functional MRI (fmri) 39

45 Neuroscience advances with imaging 40 The goal is to understand how the brain works using cognitive neuroscience. Imaging plays a major role. In fact it has been said that Imaging is one of the most important inventions in the last 1000 years!

46 Studying the brain with fmri brain connectivity and DTI fiber tracking 41

47 A Revolution in Evolution 42 Where are we going? Computers are faster than us and can store more data than us. But they lack our creativity and art and still need our guidance. But what if our minds are already quantum computers? What if we use BCI to grow our connections and our brain evolves a special ability to grow related to our connection and learning via the link to the computer? And what if we now link all 6 billion people with all the computer power in the world?

48 We will in fact create a new being Mother earth where we as individuals will be like the cells in our body and the integrated whole will be our new super-being Mother earth. 43 And imaging will have helped us get there.