Fundamentals of Special Procedures

A radiographic method of demonstrating certain anatomic features that lack natural contrast with surrounding structures by the instillation of a substance to produce natural contrast

Special procedure

are performed to identify a particular pathologic process

Diagnostic Procedures

are performed to treat the pathologic process

Interventional Procedures

Is related to number or digits

Digital

2D images that can be measured.Measurement and reproducibility are imprecise

Analog

The first studies performed as special procedures are

GI- Gastrointestinal

Gu-Genitourinary

GB-Gallbladder

The three main responsibilities of the radiographer:

Operation of the equipment.

Preparation for the procedure

Assisting the physician

The three things considered for planning a special procedure suite

Size

Location

Construction

What is the average size of a special procedure suite?

400-600 ft

Consideration for equipment selections:

Budget

Type of procedure performed

Personal preference of the radiologist

The x-ray tube should be able to withstand what?

High heat capacities

Constant Factors for Heat Units Calculation formula is what?

kVp x mA x t

For special procedures a High mA is used what is the minimum mA used?

500 mA

What’s the normal mA range used?

700-1500 mA

Why is high mA used for special procedures?

of
short exposure times needed for vascular studies

The use of the angle on the target is used to increase the effectiveness of the focal spot. The effective focal spot is smaller than the actual focal spot

Line Focus Principle

What is the advantage of using line-focus principle?

provides the detail of a small focal spot while allowing a large amount of heat dissipation

Line focus principle help reduce what?

Penumbra

For an x-ray generator there are some things to take into consideration which are what?

High mA (minimum 500mA)

Multiple phase generators

Type and number of procedures performed

linearity & reproducibility

production of a constant amount of radiation for different combinations of milliamperage and exposure time

Linearity

Exposures made at the same kVp and mA stations of the same phantom thickness should produce the same IR Exposure (DD Exposure) on the resulting image

Reproducibility

A departure from the norm

Aberration

The destruction or removal of tissue

Ablation

The image that is formed in the air by the remnant radiation that exits the object or patient.

Aerial image

A drug or chemical that has a specific affinity to certain cells and that will produce a predictable response

Agonist

Refers to the surrounding area or room

Ambient

Refers to range or width

Amplitude

A substance that is used to reduce pain

Analgesic

A continuous representation in which both measurement and reproducibility are imprecise.

Analog

Pertaining to the hypersensitivity response to a substance

Anaphylactic

To join two blood vessels

Anastomose

A localized dilation in the wall of a blood vessel.

Aneurysm

An interventional technique used to restore the opening in a stenosed vessel.

Angioplasty

A measure of the amount of spin or orbital motion of an object.

Angular momentum

Negative charged ion

Anion

A drug or chemical that will oppose or counteract the action of another drug or chemical substance by binding to a receptor site in a cell without producing a biologic response. It is the opposite of an agonist.

Antagonist