Biomaterials Laboratory Biomaterials Laboratory Martinos Center for Biomedical Imaging Martinos Center for Biomedical Imaging Massachusetts General Hospital and Harvard Medical School Massachusetts General Hospital and Harvard Medical School Group Leader: Jerry Ackerman ©1989, National Geographic Society Investigators and MGH Collaborators •Christian T. Farrar, PhD. •Gyunggoo Cho, Ph.D. (Present address: Seoul National University Hospital) •Van J. Wedeen, M.D. •Denise P. Hinton, Ph.D. •David A. Chesler, Ph.D. •Janelle Chang, Dartmouth College Children’s Hospital Collaborators Laboratory for the Study of Skeletal Disorders and Rehabilitation •Melvin J. Glimcher, M.D. •Yaotang Wu, Ph.D. •Lila Graham, Ph.D. •Jinxi Wang, M.D., Ph.D. Mission The Biomaterials Laboratory develops methods to study natural and synthetic biomaterials using magnetic resonance imaging and spectroscopy. •Bone mineral •Pathological calcification (atherosclerosis) •Synthetic calcium phosphate ceramic implants •Polymeric implants •Composite implants •Intravascular RF coils Yaotang David Denise Gyunggoo Jerry Chris Porous Porous β β - - Tricalcium Phosphate Implant Porosity Tricalcium Phosphate Implant Porosity Large Pores Small Pores Pure water 13 mm implant Proton MRI of imbibed water measures internal porosity distribution in porous structures 1 1 H Solid State MRI of Bone Matrix H Solid State MRI of Bone Matrix Single image planes from full three dimensional data set: Total proton content Same as above, except with water and fat suppression: Solid proton content (mostly collagen) Photograph of the bovine bone specimen Cortical bone Marrow Cortical bone Marrow Axial Views Longitudinal Views Projection imaging of free induction decays Wu, Ackerman, Chesler, Graham, Wang, Glimcher. Density of organic matrix of native mineralized bone measured by water and fat suppressed proton projection MRI. Magn Reson Med. 2003; 50: 59–68. Cylindrical Meanderline Coil Flat zig zag (meanderline) coil Sensitive volume Van Wedeen, 1992 Cylindrical meanderline coil Magnetic Flux Density |B|, dB Axial view Transverse view Channel for blood flow Remcom FDTD Simulation Endarterectomy Specimen 0.1 mm in plane resolution 1 mm slice thickness Birdcage transmit/ 3 mm meanderline receive 127 mm birdcage transmit/receive Meanderline coil 5 mm 3 mm diameter 6 wires Copper clad Kapton film Prototype Cylindrical Meanderline Coil Intravascular RF Coils Intravascular RF Coils Farrar CT, Wedeen VJ, Ackerman JL. The cylindrical meanderline radio frequency coil for intravascular magnetic resonance studies of atherosclerotic plaque. Magn Reson Med. In press. Full Free Space Coil Interior: Saline Immersed Experiment: 3 mm coil in water Simulation Empty Effect of Loading by Immersion of Coil Furnace Photograph Furnace Schematic 24 mm ID quartz 44 mm ID Pyrex 54 mm ID Pyrex Quadrature birdcage coil on split quartz former Ceramic fiber insulation 3 mm water jacket Thermocouple Specimen Thermocouple Noninductive heater Water out Expansion vent Expansion vent Water in Viton o-ring seals Gas out Gas in Gas out to scrubbers Aluminum end cap Not to scale Not shown: water and gas pressure gauges and pressure relief valves 2000 mm 24 mm ID quartz 24 mm ID quartz 44 mm ID Pyrex 44 mm ID Pyrex 54 mm ID Pyrex 54 mm ID Pyrex Quadrature birdcage coil on split quartz former Quadrature birdcage coil on split quartz former Ceramic fiber insulation Ceramic fiber insulation 3 mm water jacket 3 mm water jacket Thermocouple Thermocouple Specimen Specimen Thermocouple Thermocouple Noninductive heater Noninductive heater Water out Water out Expansion vent Expansion vent Expansion vent Expansion vent Water in Water in Viton o-ring seals Viton o-ring seals Gas out Gas out Gas in Gas in Gas out to scrubbers Gas out to scrubbers Aluminum end cap Aluminum end cap Not to scale Not shown: water and gas pressure gauges and pressure relief valves After 5 min After 10 min After 5 min Dewaxing of a Green β-Tricalcium Phosphate Ceramic Pellet at 200 °C by Proton MRI 1 H spin echo images of a green pellet of β-tricalcium phosphate with 50 weight % polyethylene glycol binder at 200 °C. Field of view = 120 mm, TR = 1 s, TE = 16 ms, number of pixels = 128 x 128, slice thickness = 2 mm, PEG particle size = 100 < mesh < 200. 7 Li Spin Echo Images of Molten LiCl at 700 o C Field of view = 100 mm, TR = 1 s, TE = 16 ms, number of pixels = 64x64, slice thickness = 5 mm. Transverse Top Side LiCl in the sample holder MR Compatible Furnace for In MR Compatible Furnace for In - - Situ MRI of Situ MRI of High Temperature Materials Processing High Temperature Materials Processing Cho G, Segal E, Ackerman JL. Nuclear magnetic resonance-compatible furnace for high temperature MR imaging and spectroscopy in situ. J Magn Reson. 2004; 169: 328–334. Two Dimensional Solid State NMR Spectroscopy of Bone Mineral Two Dimensional Solid State NMR Spectroscopy of Bone Mineral 1 H – 31 P heteronuclear correlation (HETCOR) cross polarization/magic angle spinning (CP/MAS) spectroscopy for structural and compositional analysis of bone mineral crystals. 30 20 10 0 -10 PPM 10 5 0 -5 PPM 31 P spectrum OH – – PO 4 –3 signal 1 H spectrum Hydroxyapatite (Ca 8 (OH) 2 (PO 4 ) 6 ) + Brushite (CaHPO 4 ·2H 2 O) test mixture HPO 4 –2 signal 30 20 10 0 -10 PPM 10 5 0 -5 PPM 31 P spectrum OH – – PO 4 –3 signal 1 H spectrum Surface water signal Bone mineral specimen Do hydroxyl ions exist in the bone mineral crystal lattice? Historical controversy: possibly not Unequivocal solid state NMR evidence: YES! Cho, Wu, Ackerman. Detection of hydroxyl ions in bone mineral by solid-state NMR spectroscopy. Science. 2003; 300: 1123–1127.
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Biomaterials LaboratoryBiomaterials LaboratoryMartinos Center for Biomedical ImagingMartinos Center for Biomedical Imaging
Massachusetts General Hospital and Harvard Medical SchoolMassachusetts General Hospital and Harvard Medical School
Group Leader: Jerry Ackerman
©1989, National Geographic Society
Investigators and MGH Collaborators•Christian T. Farrar, PhD.•Gyunggoo Cho, Ph.D. (Present address:
Seoul National University Hospital)•Van J. Wedeen, M.D.•Denise P. Hinton, Ph.D.•David A. Chesler, Ph.D.•Janelle Chang, Dartmouth College
Children’s Hospital Collaborators
Laboratory for the Studyof Skeletal Disordersand Rehabilitation•Melvin J. Glimcher, M.D.•Yaotang Wu, Ph.D.•Lila Graham, Ph.D.•Jinxi Wang, M.D., Ph.D.
MissionThe Biomaterials Laboratory develops methods to study natural and synthetic biomaterials using magnetic resonance imaging and spectroscopy.
•Bone mineral•Pathological calcification (atherosclerosis)•Synthetic calcium phosphate ceramic implants•Polymeric implants•Composite implants•Intravascular RF coils
Yaotang
David
Denise
Gyunggoo
Jerry
Chris
Porous Porous ββ--Tricalcium Phosphate Implant PorosityTricalcium Phosphate Implant Porosity
Large Pores Small Pores
Purewater
13 mmimplant
Proton MRI of imbibed water measures internalporosity distribution in porous structures
11H Solid State MRI of Bone MatrixH Solid State MRI of Bone Matrix
Single image planes from full three dimensional data set:Total proton content
Same as above, except with water and fat suppression:Solid proton content(mostly collagen)
Photograph of the bovine bone specimen
Corticalbone
Marrow
Corticalbone
Marrow
Axial Views Longitudinal Views
Projection imaging of free induction decays
Wu, Ackerman, Chesler, Graham, Wang, Glimcher. Density of organic matrix of native mineralized bone measured by water and fat suppressed proton projection MRI. Magn Reson Med. 2003; 50: 59–68.
Cylindrical Meanderline Coil
Flat zig zag (meanderline) coil
Sensitive volume
Van Wedeen, 1992Cylindrical meanderline coil
Magnetic Flux Density |B|, dB
Axial viewTransverse view
Channel forblood flow
Remcom FDTD Simulation
Endarterectomy Specimen
0.1 mm in plane resolution1 mm slice thickness
Birdcage transmit/3 mm meanderline
receive
127 mm birdcagetransmit/receive
Meanderlinecoil
5 mm
3 mm diameter6 wiresCopper cladKapton film
Prototype Cylindrical Meanderline Coil
Intravascular RF CoilsIntravascular RF Coils
Farrar CT, Wedeen VJ, Ackerman JL. The cylindrical meanderline radio frequency coil for intravascular magnetic resonance studies of atherosclerotic plaque. Magn Reson Med. In press.
Full
Free Space
Coil Interior:
Saline Immersed
Experiment:3 mm coil in water
Simulation
Empty
Effect of Loading by Immersion of Coil
Furnace PhotographFurnace Schematic
2000 mm
24 mm ID quartz
44 mm ID Pyrex
54 mm ID Pyrex
Quadrature birdcage coilon split quartz former Ceramic fiber insulation
3 mm water jacket
Thermocouple
Specimen
Thermocouple
Noninductive heater
Water outExpansion vent
Expansion vent
Water in
Viton o-ring seals
Gas out Gas in
Gas out toscrubbers
Aluminum end capNot to scale
Not shown: water and gas pressure gauges and pressure relief valves
2000 mm
24 mm ID quartz
44 mm ID Pyrex
54 mm ID Pyrex
Quadrature birdcage coilon split quartz former Ceramic fiber insulation
3 mm water jacket
Thermocouple
Specimen
Thermocouple
Noninductive heater
Water outExpansion vent
Expansion vent
Water in
Viton o-ring seals
Gas out Gas in
Gas out toscrubbers
Aluminum end capNot to scale
Not shown: water and gas pressure gauges and pressure relief valves
2000 mm2000 mm
24 mm ID quartz24 mm ID quartz
44 mm ID Pyrex44 mm ID Pyrex
54 mm ID Pyrex54 mm ID Pyrex
Quadrature birdcage coilon split quartz formerQuadrature birdcage coilon split quartz former Ceramic fiber insulationCeramic fiber insulation
3 mm water jacket3 mm water jacket
ThermocoupleThermocouple
SpecimenSpecimen
ThermocoupleThermocouple
Noninductive heaterNoninductive heater
Water outWater outExpansion ventExpansion vent
Expansion ventExpansion vent
Water inWater in
Viton o-ring sealsViton o-ring seals
Gas outGas out Gas inGas in
Gas out toscrubbersGas out toscrubbers
Aluminum end capAluminum end capNot to scale
Not shown: water and gas pressure gauges and pressure relief valves
After 5 min
After 10 min
After 5 min
Dewaxing of a Green β-Tricalcium PhosphateCeramic Pellet at 200 °C by Proton MRI
1H spin echo images of a green pellet of β-tricalcium phosphate with 50 weight % polyethylene glycol binder at 200 °C. Field of view = 120 mm, TR = 1 s, TE = 16 ms, number of pixels = 128 x 128, slice thickness = 2 mm, PEG particle size = 100 < mesh < 200.
7Li Spin Echo Images of Molten LiCl at 700 oC
Field of view = 100 mm, TR = 1 s, TE = 16 ms, number of pixels = 64x64, slice thickness = 5 mm.
Transverse
Top Side
LiCl in the sample holder
MR Compatible Furnace for InMR Compatible Furnace for In--Situ MRI ofSitu MRI ofHigh Temperature Materials ProcessingHigh Temperature Materials Processing
Cho G, Segal E, Ackerman JL. Nuclear magnetic resonance-compatible furnace for high temperature MR imaging and spectroscopy in situ. J Magn Reson. 2004; 169: 328–334.
Two Dimensional Solid State NMR Spectroscopy of Bone MineralTwo Dimensional Solid State NMR Spectroscopy of Bone Mineral
1H – 31P heteronuclear correlation (HETCOR) cross polarization/magic angle spinning (CP/MAS)spectroscopy for structural and compositional analysis of bone mineral crystals.
30 20 10 0 -10PPM
10
5
0
-5
PPM
31P spectrum
OH– – PO4–3 signal
1H spectrum
Hydroxyapatite (Ca8(OH)2(PO4)6) +Brushite (CaHPO4·2H2O) test mixture
HPO4–2 signal
30 20 10 0 -10PPM
10
5
0
-5
PPM
31P spectrum
OH– – PO4–3 signal
1H spectrum
Surface water signal
Bone mineral specimen
Do hydroxyl ions exist in thebone mineral crystal lattice?
Historical controversy:possibly not
Unequivocal solid stateNMR evidence:
YES!
Cho, Wu, Ackerman. Detection of hydroxyl ions in bone mineral by solid-state NMR spectroscopy. Science. 2003; 300: 1123–1127.
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