H's

Question 1

HIS (hospital information system)

Answer 1

Term to include all aspects of hospital information (e.g., administration, financial, clinical).

Question 2

horizontal beam radiography

Answer 2

Technique in which the x-ray beam is directed horizontally (i.e., across the x-ray table) to make a radiograph. Animal typically is standing or in lateral recumbency. Technique may be used to document presence of free fluid or gas in a body space, to reposition fluid to better visualize obscured structures, or when minimal movement of the patient is required.

Question 3

hyperparathyroidism

Answer 3

A systemic condition in which excessive production of parathyroid hormone by overactive parathyroid glands leads to abnormal loss of mineral frombone. May be primary (caused by parathyroid gland disease) or secondary (due to nutritional deficiency or chronic renal disease).

Question 4

hypertrophic osteodystrophy (HOD)

Answer 4

A systemicdisease of unknown etiology that results in subperiosteal hemorrhage and transient defects in metaphyseal mineralization. Appears on radiographs as line of decreased opacity parallel to physis and mineralization along the metaphysis. May be associated with canine distemper.

Question 5

hydrothorax

Answer 5

Accumulation of fluid within the pleural space.

Question 6

iatrogenic

Answer 6

Pathology caused by medical examination or treatment.

Question 7

idiopathic

Answer 7

Of unknown etiology; occurring without known cause.

Question 8

ileus

Answer 8

Partial or complete obstruction due to hypomotility or physical blockage. May be associated with intestine, esophagus, ureter, or bile duct.

Question 9

ill-defined

Answer 9

The margin or border of a structure is not well visualized. A simple test is whether or not you could take a pencil and easily trace the edges of the structure. When used to describe bone lesions, ill-defined osteolysis is more aggressive and ill-defined periosteal response is more active. Illdefined is not the same as irregular. Well-defined is not the same as smooth.

Question 10

infiltrate

Answer 10

Accumulation of abnormal cells in a tissue; typically describes diffuse lesions in bone or lung.

Question 11

intensifying screen

Answer 11

A plastic sheet coated with rare earth phosphorous and used to convert x-rays to visible light. Intensifying screens are mounted inside a light-proof cassette and a piece of x-ray film is placed between two screens in the cassette. Purpose of intensifying screens is to

Question 12

ground-glass appearance

Answer 12

Refers to a homogenous appearance; resembles looking through bathroom glass.

Question 13

growth arrest lines

Answer 13

Refers to thin, well-defined, horizontal lines of increased opacity in a long bone diaphysis (most common in femur). May be caused by dietary changes or systemic illness during growth.

Question 14

heel effect

Answer 14

Refers to the variation in intensity of the x-ray beam between cathode and anode sides of the x-raytube. Because the target is angled (to create a smaller effectivefocal spot), the bottom or “heel” of the focal spot absorbs some of the radiation. Absorption of some radiation on the anode side results in more x-rays being emitted from the cathode side of the x-ray tube. The thicker part of the subject should be positioned on the cathode side to take advantage of the heel effect.

Question 15

hematoma

Answer 15

A localized accumulation of blood within tissues outside of the vessels. Other names: bruise, contusion.

Question 16

hemimelia

Answer 16

Congenital partial or complete absence of a normally paired bone (e.g., radius/ulna, tibia/fibula).

Question 17

hemivertebra

Answer 17

Congenital defect resulting in only partial development of a vertebral body.

Question 18

hemothorax

Answer 18

Accumulation of blood within the pleural space.

Question 19

hernia

Answer 19

Protrusion of an organ or portion of an organ through an opening or rent (commonly in a structure that normally contains it).

Question 20

herringbone pattern

Answer 20

On a positive contrast esophagram refers to the normal transverse mucosal pattern of the distal third of the feline esophagus.

Question 21

heterotopic bone formation

Answer 21

Focal ossification in an abnormal location. Typically refers to small, well-defined, slightly irregular-shaped mineralized structures (less than 3 mm in size) in the lung. Other names: pulmonary osteomas, pulmonary microlithiasis.

Question 22

hiatus/hiatal

Answer 22

An opening, gap, or cleft; term usually is associated with the diaphragm (e.g., hiatal hernia).

Question 23

high-frequency x-ray machine

Answer 23

Type of equipment in which the electric current to the x-ray tube is manipulated to produce nearly constant potential voltage. Constant voltage results in a more uniform production of x-rays with an average energy closer to the selected kVp. With standard x-ray machines (fully rectified, single phase), the voltage rises to peak and falls to zero 120 times per second, which produces an average energy of the x-ray beam equal to onlyabout two-thirds that of the selected kVp on the control panel.