1. NMR Microscopy Stef VanGorden Joseph Hornak Rochester Institute of Technology

2. Objective The main goal of this research was to create a NMR microscope capable of producing a 1 mm thick, approximately 112 micron in-plane resolution tomographic images. Bruker 300 DRX Spectrometer

3. Overview of my Presentation Background Experimental Applications Conclusions

4. BACKGROUND

5. E = h  h  B (Hornak 1997)  B  z/T Energy Level Diagram

6. GyGy Sample with a Uniform Field (Hornak 1997) Hydrogen Molecules S N

7. Sample with Increasing Gradient GyGy (Hornak 1997)  B =  x G x Hydrogen Molecules

8. EXPERIMENTAL

9. Starting Point Reproduction of previous 1-D and 2-D imaging results. Slice Selective Sequence Evaluation

10. Slice Selective Sequence Slice Selective Case (tomographic slice) GzGz GyGy GxGx

11. Timing Diagram for the Slice Selective NMR Microscope

12. Variables Thick Slice (From ~1mm to ~10 mm) Width of 90° pulse = 80 µs tw (180°) =160 µs Amplitude attenuation = 20 dB Thin Slice (From ~.5 mm to ~1 mm) Width of 90° pulse = 157 µs tw (180°) = 314 µs Amplitude attenuation = 26 dB THK = 2/(  G z t w )

13. Applying Gradients THK = 2/(  G z t w ) 100% =50 G/cm Maximum 10% = 5 G/cm => 6 mm 60% = 30 G/cm => 1 mm

14. Feature Documentation In-plane Resolution Phantoms Slice Thickness Phantoms

15. In-plane Resolution

16. Fishing line in capillary tubesGlass rods 112  m 284  m

17. In-plane Resolution 45  m -- 112  m object --- image 1 pixel = 23.7  m

18. Slice Thickness Phantom Screw phantom in sample tube Signal from the screw phantom. THK = (  (1/32 in/threads)(25.4 mm/in) THK =.8 mm for an angle of 360°

19. Nylon Screw Phantom Images z y x y x y x y x y One or more rotations Less than one rotation

20. Cone Phantom Design Illustration of Cone Phantom

21. Cone Phantom Images Images with slice thickness of 1mm and.5 mm respectively..711 mm

22. 4° Portion of Sample Tube (profile of middle) Analyzing Wedge Images.55mm 4.25mm

23. APPLICATIONS

24. Celery Images Day 1: ImagesTwo Weeks Later Thick sliceThinner slice Thinnest slice

25. House Fly Image

26. Conclusion Moved practical NMR microscopy at RIT closer to reality. Current Capabilities slice thickness ~.5 mm in-plane resolution ~ 100 microns

27. The Next Step... Slice Selection Locator SNR improvements Further In-plane Resolution Evaluation x y Slice Selection Locator