Mid Term Revision

1. Mid Term Revision Radiology Basic 0233 Dr Mohamed El Safwany, MD.

2. Medical Imaging Radiography Plain Film/ X-Ray/ Roentgen Rays Computed Tomography (CT Scan) DEXA Bone Scan Magnetic Resonance Image (MRI)

3. Basic Concepts What is an X-Ray? Electromagnetic Radiation - short wavelength

4. Radiodensity When an object absorbs the X-rays - fewer protons produced, film stays light Radiopaque Radiolucent • X-rays not absorbed, screen produces photons when struck, and exposes the film, turning it dark

5. What do I need to look for in foot trauma? Distal tibia and fibula F- fifth metatarsal base L- lateral process of the talus O- os trigonum A- anterior process of the calcaneus T- talar dome

6. Viewing Images • X-ray study named for the direction the beam travels • AP • PA • Lateral • Orient film as if you were facing the patient, his/her Left will be on your Right

7. Viewing Images • A radiograph is a two dimensional representation • Therefore, “One View is No View” • Two views are needed, ideally at 90 degrees to one another for proper 3-D like interpretation

8. Computed Tomography (CT) X-Ray beam moves 360 around the patient Consecutive x-ray “slices” around the patient Computer can recreate 3D image of the body Best for evaluating bone and soft tissue tumors, fractures, intra-articular abnormalities, and bone mineral analysis

9. Magnetic Resonance Imaging (MRI) What is a MRI? The use of a High Power Magnet (.3 -2.0 Teslas) To align hydrogen atoms in the body to which a radio wave frequency is applied to produce an image

10. T1 Vs T2 • T1 • Tissue with high water content will apear dark (grey) T2 Tissue with high water content will appear white/ brighter

11. Shoulder - MRI – Coronal Plane Rotator Cuff SS Tendon Acr -- Clav Supraspinatus Glenoid Fluid in Joint

12. What is a Bone Fracture? “A bone fracture is a medical condition in which there is a break in the continuity of the bone. A bone fracture can be the result of high force impact or stress, or trivial injury as a result of certain medical conditions that weaken the bones, such as osteoporosis, and bone cancer.”

13. * A fracture is a broken bone that depending upon physical pressure or stress that was exerted on the bone ,it can be a large or small fracture. • Symptoms of a fracture are: swelling, deformity, pain, and loss of function. • Treatment for fracture is to get an x-ray, reduction, fixation, surgery, and rehabilitation.

14. Types of Fractures There are several types of fractures such as closed, comminuted, compound, compression, fracture, greenstick, impacted, oblique, pathologic, spiral, stress, and transverse.

15. Skeletal Imaging Majority are diagnosed by plain radiograph AP and Lateral projections Oblique views for trauma involving joints, hands and feet CT - fine bone structure ( skull,spine and pelvis) MRI - evaluation of soft tissue Nuclear medicine - bone metastases, osteomyelitis and occult trauma (stress fractures)

16. Skeletal Imaging Most bone lesions are obvious on clinical history >95 % bone films are obtained for: Evaluation of trauma Eval. Arthritis Eval. Degenerative conditions Metastases

17. Strains May result in pathologic changes of the soft-tissue and bones: tendon degeneration, osteophytes, stress fractures, or nerve entrapment. also graded as mild, moderate or severe. Severe strains are characterized by rupture of any part of the tendon complex e.g biceps, patella or Achilles. Diagnosed by Ultrasound and MRI.

18. Fracture Description Fractures are further described based on: Location Pattern Displacement When describing location, the bone affected is identified as well as the specific part of the bone involved (proximal or distal epiphysis,etc.)

19. Clavicle fracture • Most common bone fractured • Weakest aspect is the junction of middle/distal thirds • Look for “Tenting” of the skin • Class A (middle third fractures) (80%). • Class B (distal third fractures) (15%). • Class C (proximal third) (5%)

20. The Wrist-Eight Carpal Bones + Radius and Ulna • Proximal / Distal row from radial to ulnar position Scaphoid,Lunate,Triquetrum,Pisiform, Trapezium,Trapezoid,Capitate,Hamate

21. Scaphoid Fractures • Most common fracture carpal bone • There is no direct blood supply to the proximal portion of the scaphoid • Therefore, scaphoid fracture have a tendency to develop delayed union or avascular necrosis • Mechanism of injury • Forceful hyperextension of the wrist

22. Knee • Standard Xray projections: • AP – evaluate joint space narrowing / calcifications • Lateral –evaluates .Patella / effusions • Special views • Sunrise / merchant view • Tangential / knee flexed/from top-down • Tunnel view • Knee more flexed, looking through the “tunnel created by the femoral condyles

24. Meniscal Tear Most Common injury to the knee requiring surgery Medial meniscal tears occur 3 times more frequently than lateral meniscal tears Locked knee requires urgent intervention

26. Unhappy Triad This is the term given to an injury where the ACL, MCL and Medial Meniscus are all three torn.  The mechanism for this injury is usually a lateral blow to the knee with the foot fixed.  1. ACL tear 2. MCL tear 3. Medial meniscus tear

27. Chronic Knee Pain • Degenerative OA • X ray findings • joint space narrowing (Medial common) • Spurs, osteophytes • Sclerotic bony margins

28. Artificial knee replacement

30. Hip dislocations • From M V Accidents • Most common posterior dislocation • On AP - head of femur located superiorly and laterally displaced • Anterior dislocation: inferior and medial • Look for associated fracture fragments from the acetabulum

32. Aseptic necrosis hips • Xray changes • Flattening, irregularity, sclerosis of superior aspect femoral head(late) • Early findings on MRI/bone scan • Caused by trauma and chronic steroid use

33. Slipped Capital Epiphysis

34. Good Luck