P's

Question 1

periosteum

Answer 1

Tough layer of vascular connective tissue that covers outer surfaces of all bones except at the joint surfaces. Periosteum is responsible for circumferential growth of immature long bones and provides healing response when bone is damaged.

Question 2

pes

Answer 2

Distal part of a pelvic limb; includes tarsus, metatarsus, and digits.

Question 3

phosphor

Answer 3

A rare-earth compound that emits an instantaneous flash of light after interaction with an x-ray. The light is phosphorescence rather than fluorescence (latter glows for a longer period of time).

Question 4

physis

Answer 4

The cartilaginous growth plate located between the metaphysis and the epiphysis of an immature long bone. Other names: epiphyseal plate, growth plate.

Question 5

physeal fracture

Answer 5

A break in bone that occurs through a physis (occurs in immature animals). Fracture commonly is described using Salter–Harris classification.

Question 6

phytobezoar

Answer 6

A concretion of plant material (fruit and/or vegetable fibers) within the alimentary tract (usually stomach or intestine).

Question 7

plantar

Answer 7

Associated with the sole of the foot; refers to the bottom surface of a distal pelvic limb or pes (Figure 2.22). Opposite of dorsal when referring to a limb.

Question 8

pleural fissure line

Answer 8

Linear increased opacity between lung lobes. May represent pleural thickening (line is uniform in thickness and does not taper), pleural effusion (line widens peripherally and tapers toward the hilus), or interlobar fat (line is wider centrally and tapers peripherally). Other names: interlobar fissure line, fissure line.

Question 9

pleural thickening

Answer 9

Increased width and opacity of parietal or visceral pleura due to deposits of fibrin or mineral.

Question 10

pleurography

Answer 10

A radiographic contrast study of the parietal and visceral pleural surfaces made by instilling contrast medium into the pleural space.

Question 11

plication

Answer 11

Abnormal bunching of small intestine with tight turns and irregular pockets of gas, commonly caused by linear foreign material. Other names: pleating.

Question 12

pneumatocoele:

Answer 12

An air-filled cyst in a lung; usually results from trauma.

Question 13

pneumomediastinum

Answer 13

Presence of free gas in the mediastinum (aorta, esophagus, cranial vessels) appear sharp and well-defined; results in visualization of mediastinal structures not normally seen. If only the “dorsal outer tracheal margin” is visible, gas is present in the esophagus (megaesophagus). If both dorsal and ventral outer margins of trachea are visible, gas is in mediastinum (pnumomediastinum)

Question 14

pneumopericardiography

Answer 14

A radiographic contrast study of the pericardial space; used to evaluate the pericardial sac, epicardial surface of the heart, and origin of the aorta and pulmonary arteries. Typically performed by instilling gas in the pericardial sac.

Question 15

PACS (picture archiving and communication system)

Answer 15

a network of computers used to accomplish many of the services required in digital radiography:

P Pictures made available for viewing, interpretation, reporting, and consultation from multiple modalities (radiology, ultrasound, CT, MRI, etc.).

A Archiving and storage of imaging studies for both short and long terms.

C Communication with local and remote computers, professionals, and consultants to manage workflow and share information.

S System coordination and integration to works with radiology information systems (RIS), hospital information systems (HIS), and others to enable a paperless environment.

Question 16

palmar

Answer 16

Associated with the palm of the hand; refers tothe bottom surface of a distal thoracic limb or manus (Figure 2.22). Opposed to dorsal when referring to a limb.

Question 17

panosteitis

Answer 17

A self-limiting bone disorder of unknown

etiology that causes an acute onset of pain in one or more bones. Multiple bones may be affected either simultaneously or sequentially and lameness commonly shifts between legs. Appears on radiographs as areas of increased medullaryopacity, typically near a nutrient foramen, and sometimes with a periosteal response.

Question 18

parosteal osteosarcoma

Answer 18

A rare, slow-growing bone tumor that arises from the surface of the bone instead of the intramedullary region. Commonly appears as a smoothbordered, nonaggressive bony mass arising from the surface of the bone.

Question 19

patchy

Answer 19

Refers to multiple, indistinct, irregularly shaped lesions; commonly used to describe amorphous areas of

increased opacity in the lungs.

Question 20

pathologic fracture

Answer 20

A loss of continuity in a bone that has been weakened by an underlying disease process or developmental defect; typically caused by neoplasia or metabolic bone disease.

Question 21

penumbra

Answer 21

The partial outer shadows that blur the edgesof structures and decrease radiographic detail. Occurs due to the fact that x-rays do not originate from a single point but are generated over a small area. Penumbra can be minimized by using a small focal spot, a longer distance between focal spot and image detector, and a shorter distance between patient (subject or object) and imaging detector. Other names: geometric unsharpness.

Question 22

periosteal response

Answer 22

Formation of new bone to fill the space created when the periosteum is separated from the cortex. New bone forms perpendicular to the periosteum. The appearance of the margin of the periosteal new bone formation reflects the activity of the disease process (the less distinct the margin, the more active the disease process).

Question 23

pulmonary emphysema

Answer 23

Refers to increased size of air spaces distal to the terminal bronchiole, with destruction of alveolar walls.

Question 24

portography

Answer 24

A radiographic contrast study of the portal venous system. Contrast agent is injected into a mesenteric vein (venous portography) or the spleen (splenoportography).

Question 25

pyothorax

Answer 25

Accumulation of purulent exudate in the pleural space.

Question 26

pyelogram

Answer 26

The phase in excretory urography during which contrast medium opacifies the renal collecting system (e.g., renal pelvis, pelvic recesses).

Question 27

pneumoperitoneum

Answer 27

Free gas in the peritoneal space.

Question 28

pneumoperitoneography

Answer 28

A radiographic contrast study of the peritoneal space; gas is instilled into the peritoneal space.

Question 29

pneumothorax

Answer 29

Presence of free gas in the pleural space.

• Simple pneumothorax: air in pleural space is less than or equal to atmospheric pressure.
• Closed pneumothorax: a simple pneumothorax in which the thoracic wall is intact.
• Open pneumothorax: a simple pneumothorax caused by an opening in the thoracic wall.
• Tension pneumothorax: a closed pneumothorax in which pressure within the pleural space is greater than atmospheric pressure, resulting in compression atelectasis of the lung(s).

Question 30

polyarticular

Answer 30

Associated with multiple joints

Question 31

polyarthritis

Answer 31

Inflammation affecting multiple joints.

Question 32

polydactyly

Answer 32

Congenital anomaly in which one or more extra digits are present.

Question 33

polyostotic

Answer 33

Associated with multiple bones.

Question 34

poorly-defined

Answer 34

Similar meaning to ill-defined, but sometimes used as a qualifier when making a decision between well-defined and ill-defined. Such a lesion should be reevaluated in a week or so, especially if the lesion margins are becoming better-defined on serial radiographs, but not quite well-defined.

Question 35

positive contrast agent

Answer 35

A contrast medium that absorbs many x-rays and is more opaque than soft tissue or bone (e.g., barium sulfate, organic iodinated compounds).

Question 36

pronate

Answer 36

To rotate a limb inward so that the palmar or plantar surface faces downward or lateral and the dorsal or cranial surface faces upward or medial.

Question 37

proximal

Answer 37

Anatomical term describing part of a limbnearest its attachment to the body. Contrast distal (Figure 2.22).

Question 38

pseudoarthrosis

Answer 38

“False joint”; a fibrous capsule filled with serum that may form at the site of a long-term nonunion fracture, chronic dislocation, or developmental anomaly.

Question 39

pseudo-nodule

Answer 39

A discrete soft tissue or mineral opacity that mimics a pulmonary nodule (e.g., end-on visualization of a pulmonary vessel, superimposed nipple, costochondral junction, heterotopic bone formation).

Question 40

Peribronchial cuffing

Answer 40

Outer bronchial margins may become indistinct due to disease in adjacent lung parenchyma or peribronchial infiltrates. When viewed tangentially this can give the appearance of a tram line. It is sometimes described as a “donut sign”. It may either represent bronchial wall thickening or fluid around bronchi when seen end on due to lymphatic congestion. It can be seen in with a number of pathologies which include: pulmonary oedema, small air ways inflammatory disease, bronchiolitis , asthma (C on image)