Dr.Biery, Radiologist @ VHUP: radiology clinical correlation. assisted by Drs Walker and Keith. [slide-radiograph of the liberty bell :)] an example of industrial radiology imaging in veterinary radiology - xrays generated by xray machine. photons come out which have specific properties, some similar to other forms of emag radiation, but xrays have very short wavelength. [slide- portable xray machine] [slide- large xray machine in hospital] xrays can't be sensed by smell, touch,sight, taste, hearing xray film has to be in a lightresistant container - cassette [slide-film cassette] xray film becomes a radiograph after it is exposed and developed. different kinds of film are used for different body parts. radiograph is analgous to a photograph. it is NOT an xray. the xray is used to MAKE the radiograph. after exposure the radiograph is developed by hand or in a machine. basedon thickness of tissue, color on rad changes. the denser the material, the whiter the film. the lighter the material, the blacker the film. [slide-tbone steak] most radioopaque | bone soft tissue: muscle,blood, fluid fat air most radiolucent [slide- heart, spade, club; all superimposed] demonstrated cumulative opacity of pieces of paper. [slide-radiograph of purse] [slide-radiograph of swiss cheese][slide-boy with afghan hound] [slide-two views of coffeepot] [slide-scapula, lateral view.] think when you look at structures in one view, what it will look like in another view. [slide- AP view of scapula] note that AP view shows height of spine of scapula much better, but you can't see lateral surface. [slide-lat and AP view of forelimb with fx radius visible only on AP view. note that the dog is young, growth plates were open] [slide-apple, pear, half an apple, cherries] note that a REAL apple shows up w/internal strucure visible; fake fruit has increased density around edges, no internal structure. [slide- pelvic limb, stifle. increased soft tissue density surrounding joint; cloudiness and spidery stuff. lateral view shows that bones are all normal, and the swelling/mineralization is all caudal to the joint. turned out to be a malignant tumor. ] good example of why you need two views of everything. need to be/have familiar w/radiographic anatomy systematic method of examination knowledge of dz and radiographic patterns of dz knowledge of dz incidence relative to signalment knowledge of anatomic directional terms. think about how to position animal to get a particular picture of something. [slide:radius and ulna] number, size, shape, position, density: interpretation of survey radiographs. how many structures? is shape, size, normal? is position normal? in small dog, ulna is very tiny, small diameter compared to radius. In large breed, ulna should be about same diameter as radius. [slide of radii and ulnae] [slide: correct position for med/lat view of elbow in dog] shows ununited anconeal process. many specialized xray techniques exist. [slide: k9 pelvic limb, flexed stifle. soft tissue/fascial planes kind of fuzzy. then other view shows gastrnocnemius, tendon outlines clear. Dr.Biery did that by deliberately putting air into the fascia. Could see that in traumatic injury as well.] lymphangiogram - contrast dye added to lymphatic system - highlights nodes, vessels of lymphatic system. arteriogram- as above, arteries. slide shows dog w/severed main tibial artery secondary to gunshot wound. kidney contrast studies, bladder contrast studies - showed slide w/poodle w/only one kidney showing due to a bladder tumor. renal pelvis of cat looks different than that of dog. normal cat looks like pyelonephritis in dog. note that if you diagnose an abnormality from a radiograph of a normal structure, the pet will do well on antibiotics... :) other techniques: ultrasound, Computerized tomography (CT, CAT), nuclear magnatic resonance/magnetic resonance imaging (NMR, MRI) ultrasound machine has transducer, "probe", which sends out ultrasound waves - resulting echo viewed on screen. In U/S, fluid doesn't echo, so it's black instead of showing up as cloudy like on a radiograph. nuclear medicine..inject radioactive drug, image target organ. use gamma camera. scintigraphy this is called. showed scintograph of horse leg w/increased uptake of radioactive material indicating a stress fracture that wasn't visible on a radiograph. cat scintograph shows increased uptake of iodine in brain indicative of tumor. MRI [slide of MR magnet][slide-MR of canine head-brain looks really small :)] these imaging techniques will show you consecutive slices of the region of the body being studied. Cross sectional anatomy can be very important. Radiation safety. must remember to follow guidelines. it IS appropriate and legal to stay in room w/animal. Stay OUT of primary beam, wear aprons and gloves, use appropriate technique. Stay as far as possible away from area of radiation. Always use gloves and aprons. Reduce time of exposure as much as possible. there are 32 different commercially available devices to hold a cassette next to a horse's leg w/o being too close. fatal risk of 1/1,000,000 of dying from cancer from radiation if you hold 120 dogs for radiographs a day every day for 30 years is LESS than risk of dying from 40 TB of peanut butter going 300 mi in a car, spending 2 days in NY, having 100 charbroiled steaks, having 1.5 cigarettes. risk of cancer from full time radiology work is equivalent to 2 months in denver. flea slide....magnified.