Agenda. Magnetic Resonance Imaging. MRI Advantages. Ankle in Three Planes

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1 Magnetic Resonance Imaging Todd Van Auken M.Ed. RT (R)(MR) Agenda Advantages g of MRI Types y of Exams Performed Equipmentq p Basic Physics Safetyy Images g of Anatomy and Pathology Career Opportunities MRI Advantages Ankle in Three Planes No Harmful Biological Effects Cross ss-sectional Images In Any Plane Exquisite Tissue Differentiation

2 Exams Performed Exams Performed Brain IAC Orbits Pituitary C-Spine Soft Tissue Neck T-spine L-spine Sacrum Exams Performed Shoulder Elbow Wrist Hand Liver Pancreas MRCP Adrenal Glands Kidneys Exams Performed Pelvis

3 Hips Femur Knee Lower Leg Exams Performed MRA Head Neck Arch Upper Extremity Renal Aorta Runoff Exams Performed Foot/Ankle Exams Performed Breast Cardiac Equipment Permanent P ent Magnet - A magnet composed of hundreds of permanently magnetized bricks Defacography Prostate Electromagnet E t - A magnet made from coils of wire through which an electrical current is passed

4 Magnet Strength Tesla The unit used to express s magnetic field strength 1 Tesla = 20,000 times the earth s magnetic field Diagnostic MRI machines range from.3 T 3.0 T Equipment RF Coil An antenna used to transmit and/or receive radio frequency energy Gadolinium rare Earth mineral with magnetic propertiesp Brain, Abdomen, Spine with Hx of MS, Post st-op Lumbar, MRA, Arthrogram, ra Soft Tissues Mass, Osteomyelitis, Breast Contrast Exams Basic Physics Protons in a Magnet Radio Frequency Energy Resonance e The physical principle that allows energy to be transferred efficiently from one object to the other, causing the receiving object to vibrate at the same frequency as the sender An Image

5 Protons ¾A proton p contains a p positive charge g ¾U Under n normal norm o conditions, protons spin randomlyy ¾ Whe When W h positively sitively charged ge particle parti particless spin p on their axes,, theyy make a small magnetic g field ¾ H Hydrogen og n Atoms t ms A Abundant bundant in the bo body and contain only one proton in their nucleus How an MRI Scanner Works T The magnet causes auses ses the e protons rotons ro to liline u up together gethe and a spin in the same direction on n llik like ikkke toyy tops p Th The radio T ra frequency re uen signal is beamed into the magnetic g field T The e RF RF signal s g l makes the protons move out of alignment g W When Wh en n the signal stops, s, the protons pr m move back ba b bac a k to ttheir aligned positions and release energy How an MRI Scanner Works A receiverr coil measures sures the ene energy ener y released leased by the disturbed isturbed protons pro and a d the amount of time it takes for them to realign g T These h measurements ents provide pr informati information informa about a ab out utt the t type of tissue in wh which whic tthe h protons lie,, as well as its condition p A computer comp usess this information info or to construct a digital image on a monitor

6 T1 and T2 Images Other Planes Safety Who should know MR Safety? All inn-house personnel that have reason to enter e the MR suite area should be trained in MR safety procedures: MR technologists, o imaging personnel, students, s transporters, s, and other medical staff Maintenance n and janitorial personnel

7 Controlled Access Area Although not detectable ec by the human senses, a magnetic field can be dangerous to equipment and to people p For the safety of patients and personnel, el, controlled access areas are established These e areas as are off fff-limits by anyone unless accompanied by a trained MRI technologist Controlled Access Area The area is labeled with the use of warning signs s and markings to prevent e the entry of ferromagnetic objects into the controlled access area and to limit the access of individuals with medical implants near high magnetic fields. Fatal Accidents CAN Happen! Be mindful of what you bring into the room!

8 Be careful of these items also! Metal Objects Becoming Projectiles Examples of items inn-house personnel may have that can become projectiles if brought into the magnetic field MR technologists, students, researchers, transporters & other medical personnel Scissors, Hemostats Scalpels, Syringes, Needles Stethoscopes Oxygen Cylinders Gurneys, Wheelchairs Clipboards, Metal Pens Maintenance & Janitorial personnel Dustpans Buckets Buffers Vacuum Cleaners Tools Tool Kits Who else should know MR Safety? Public safety forces that may respond to an emergency in or near the MR suite should be briefed on the potential hazards of the MR equipment. Fire department personnel Law enforcement personnel

9 Examples of items public safety forces may have that can become projectiles if brought into the magnetic field Law Enforcement personnel Guns Fire Department personnel Axes Absolute Contraindications Cardiac Pacemakers/Defibrillators and Ferromagnetic Aneurysm Clips Knives Handcuffs Clipboards Flashlights Hose couplings Nozzles Pike poles Fire Extinguishers Breathing apparatus Absolute Contraindications Be careful of fresh tattoos! Cardiac Pacemakersa (except in rare, controlled environments) Cochlear (inner ear) implants Swan an- n-ganz catheters with thermodilution tips Ferromagnetic or unidentifiable aneurysm clips of the brain Implanted neuro stimulators Metal or unidentifiable foreign bodies in the eyes Shrapnel near a vital organ Two models of penile implants

10 Example of MRI Screening Sheet ACL/MCL Tear Normal ACL Normal PCL

11 ACL, PCL, MCL Tear ACL Tear PCL Tear Meniscus Tear

12 Baker s Cyst Lymphoma Metastasis Intramuscular Hematoma Intramuscular Hematoma

13 Lateral Malleolus Fracture and Tear of the Tibiofibular Ligament Brain Metastasis Brain Metastasis Brain Metastasis

14 Acoustic Neuroma Meningioma Meningioma Meningioma

15 Meningioma Arteriovenous Malformation AVM Calcified Lipoma in Corpus Callosum

16 Right Mid-Cerebral Artery Infarct Orbital Mass Orbital Mass Arachnoid Cyst

17 Normal Spine Abnormal Spine Hemangioma Herniated Disc

18 Nerve Root Sheath Tumor Nerve Root Sheath Tumor Spine Metastasis Spine Metastasis

19 Spine Metastasis Spine Metastasis Compression Fracture Seroma

20 Incidental Findings AAA/Sat Band Psoas Muscle Hemorrhage Hardware

21 Syrinx Syrinx Syrinx Abdominal MRA/MRV

22 Normal Appearing Axial Brain Brain Aneurysm Brain Aneurysm Brain Aneurysm

23 Brain Aneurysm Brain Aneurysm Brain Aneurysm Abdominal MRA

24 Kidney Transplant MRA Runoff Left Thigh MRA Lower Leg MRA

25 Breast CA Mets in Liver Liver Hemangioma Liver Hemangioma Liver Hemangioma

26 Gallstones MRCP Polycystic Kidneys Polycystic Kidneys

27 Enlarged Uterus Enlarged Uterus Pelvis Sarcoma Pelvis Sarcoma

28 Breast Cancer Breast Cancer Breast Cancer What is it??

29 Fetus!! Other Uses Functional F MRI- measures split- t-second nerve cell activity in parts of the brain Spectroscopic MRI RI- measures s the amounts of certain metabolites in the body Diffusion D fus o MRI- creates an image based on the microscopic opic movements of water in the spaces outside of cells Career Opportunities Applications Specialist Sales