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Low

Until

recently,

screen, the has

the

calcium

developed

tungstate

by Thomas

between

dating

that

screens no

major

phosphor

intensifying

in

has

imaging. 50 years

of

various

in the

1896.

system

of rare-earth

intensifying screens and x-ray-to-light

version These

tungstate to provide

efficiency new screens,

comparable

to

exposure, field

than calcium which seem

calcium

represent

of low

Early duction

tungstate

a major

dose

at

the

is to

ence

of dedicated

we became interested for use in pediatric (Tnimax, has now

3M been

Co., used

rare-earth

primary

goal

was

pediatric radiographic atnic radiographic system.

Determination

on subjective vious and

experience:

to

initial

which

(graininess). only

twice

nation as fast

only

as fast

had

mildly

as par

as

has

].

two

These

can

high

4-XD

combination

had

minimally

increased

noise

par

speed. noise

Since

the

terbium

The and

alpha was

increased

of

#{149} Initial

study

grant

Institutes

of

funded

no.

5-501

by

U.S.

Public

RRO5357-13,

Health

GAS

Service

481

general

from

the

study

produced

was

low

and

the

was

with

a

systems,

we

of the

radiography. 600

was

an or

were

the

apparent

iodine-con-

tissues.

Chest study.

and These

quality. Initially, was unsatisfactory This alpha

detail due

has recently been 4 screen (recently

XD film. The speed of this times par, resulting in a 50% [6].

in bone

The

visibility

of

detail

indistinguishable

radiographs.

from

With

now

have

a functional

for

the

entire

the

use

system

of

spectrum

of

radiology. slightly

justified

by

higher the

cost

marked secondary

reducas well

decreased. allows very

The increased short exposure

retakes

of previous

due

to patient

potential

for Hopefully

rare-earth

dosage

portable the

with

speed times, The

may

be

radiation

dosage

speed

systems).

par to

personnel

has

of the rare-earth system virtually eliminating film

This

is extremely

system equipment.

enhances It thus

radiography difficulty

system

in

radiation

motion.

in pediatric radiography. power of old or low-power limitations.

of the reduction

(25%-5O%

1066

published relative with

about

of

is virtually

radiography

The

dous

The

bariumbulk

in newborns

Concomitantly,

National

with

dose

There

the

with is two

noise

Health.

is

urographic examinations. on examinations utilizing

of satisfactory chest films

times

research

our

system

an evaluation

low

background

up

as evidenced

pediatric

was

are

from

8-XD

performed,

combination

dose

speed

rather

significantly

between

made

reduction

two

but

alpha

excellent.

commercially) at 80 kVp

speed

a constant

speed at 60 kVp, four and a half times faster

decreases

of contrast

new

have

the

examinations

films

of these

combi-

four

level

seemed justified in view of the additional exposure tion, alpha 8-XD was chosen for all routine work as photo-timed fluoroscopic spot films.

support

par

excellent

about

also of this

films

structures

of this

overcome

(4].

contrast

dosage

noise

8-XD

product

was

in exact agreement simulating phantom.

system

of the

available combination

be used in XM (extra

but

end

hurdle

For instance,

to excessive radiographic mottle. overcome by the use of a modified

noise

of

beam

persever-

systems,

fasten than par kVp, and three

exams were generally on bone and newborn

screens:

levels

the

abdominal

in four possibilities. alpha 4-XM yielded

unacceptably

x-ray

taming

from

Tb)

25

of

softer

positive

pre-

and

speed

at the

the

dependent.

This is not on an adult

dependence energy

Through

do not

in children

proved the lack

Much of the agony of be avoided by studying published [1, 5]. The

tungstate

filtration

times at 80

enhancement

film-sceen

film:

resulting 8-XM and

increased speed.

system

8 (faster) [1 green-sensitive

alpha

with

a basic contrast,

(Gd 20

had

The

resolution

study

in general

calcium

strong beam

this

barium studies and 1.500 were In general, radiographic quality

screens

results

the

effective

radiographers

Of the 20,000

based

from

speed

screen

oxysulfide

(detail). alpha

films

par

resolution, Trimax

alpha with

and XD tests with

radiographs

speed

of the

The

gadolinium

alpha 4 (fast) and any combination mottle) Early

par

stage

with

on

implemented.

experience three faster

The

dose

was

and

quality

the main pedito the Tnimax

quality

using

acceptable

be chosen.

film

comparison

with

with

activated

dose

conducted

comparison

combination

To this end converted

of low

examinations

other rooms. During the had

system. room was

low

kilovoltage

at 100 kVp. data based

St. Paul, Minn.) was in oven 20,000 routine

a functional

to

almost times

in this dosage reradiology. A rare-

to establish

was

systems

in relation clinical

a new

pediatric examinations. Our clinical experience with this system is reviewed here. The physical characteristics of the various low dose systems have been reported [1, 5]. The

concerning

speed

system

technique charts prime reason was

and a functional system obtained. technique conversion can now relative speed diagrams recently

[1-4]. quality

into

screen

time

radiation

advance

radiographic at first. The

information

relative

mdi-

with con-

screens image

reduced

technical

of

radiography.

in 1974 potential

earth system instituted and

of adequate

phosphors

has led to a new generation of greater x-ray absorption efficiency

Radiology

Establishment of exceedingly difficult

been

manufacturers, in this

use

in Pediatric

Little improvement and little difference

advancement

be expected. Recent development

Radiography

Edison

mainstay of radiologic been made in the past

exists

Dose

Editorials

within

in setting

important the effective has tremenequipment up technique

1067

EDITORIALS

charts

can be avoided

by use of recently

information concerning Low dose radiography

[71. portable

Downloaded from www.ajronline.org by 117.253.243.48 on 10/07/15 from IP address 117.253.243.48. Copyright ARRS. For personal use only; all rights reserved

angiography

[81. and now, of

functional

low

to apply

the

dose

and

The

adults

a striking reduction medical radiation.

technology

in its

certainly

infancy.

are yet

technique

in

for

the

of

be easy

dose

radio-

age

screen

technology

and

refinements

to come. Richard

6. Wesenberg

L. Wesenbeng

Raymond

Saskia v. W. Hilton Joel 0. Blumhagen

University

of Colorado Denver,

lation

from

resistance and

fetal

to

is characterized and

ductus

normal

functional

adaptive

hypoxemia

secondary

of the

in two

hemodynamic

over

in eight

8 year

an

experience

but

genital

heart

only

Within

the

of the

fetal

a wide

[4-71, lung

adaptation Cardiac usually

(W. past

infants

could M

year,

circulation

.

be

with

inclusive

the

entity

in the newborn catheterization

and

for

this

have

with

led to

are found

hypoxemia

helpful

1 14:

ruling

abnormalities.

In

ductal

determinations

night

radial

arteries

night-to-left

and

shunting

heart

and

simultaneous

pre-

descending

vessels,

bed

catheterization

the

size

structural

heart

[4, 51. We found in

disease

no

infants

only

of

cannot

typical the

addition

to

rare

parenchymal abnormalities disease, meconium aspiration and

a poorly

not

out

of

that

the

chest

proportion film.

normal

defined

to the This

lungs,

pattern

In most the degree

a

when excluded

of retained

the this of

,hyaline pneulung

fluid

on without pulwas generally

abnormality has

of of

number

including syndrome,

cases, with of hypoxemia

pulmonary

observation

be

pattern

In

as

Cardiac

appearance

hemodynamic

pulmonary membrane monia,

level

such pulmonary

instances

otherwise

condition.

were encountered. monany disease.

at the

vasospasm.

radiographic

with

function, pulmonary

shunting

in the

Pre-

structure

and

evidence

in identifying

is required

on

document

arteriosus.

assess

as demonstrate

post-

temporal may

ductus to

chamber

presumptive

cardiac and

from aorta

the

a fixed

electnocandio-

structural

is used

great

normal

of

out

some

through

provide

rules

obtained

echocardiography may

A

out

addition,

administration

effectively

shunt.

in

oxygen

with

infants

right-to-left

is

lungs

cardiopulmonary

We

intracardiac gram

of in many

is useful

of persistence

angiocandiography

correction oxygen

vascular

cardiac

high-speed

A Commentary

ovale [10]. A trial of a vasodilator test the responsiveness of the

I 91. diagnosis.

of

Radiology

as well

con-

have

evaluation

angiography.

hypertension

communication).

reports

K: The

in

of the foramen tolazoline to

radiographic presentations of an animal model links abnormal

Radiation exposure in Radiology 122:

newborn.

ab-

clinical

in infants

WA:

the

131

gathered

without

A, Amplatz

combinations

1 00%

and

the

cyanotic

.

of

normal

in whom

of

1977

initial

of the

series

identified

1975

with

disease. et al.

their

out

449-452.

sently

represent

I 81 These

concept

essential

This

Moore

of abnormal

of

pattern

been

pensis-

of pulmonary

personal

circulatory

has

this

of lung Silvenstein

ruled

Gensony.

range of clinical and and a recent description

disease

a more

those

not

this

fetal channels the term pensis-

infants

infants.

does

disease

catheterization

and

characteristic

newborn

period

of

of severe

documentation pattern

ovale

failure

syndrome

evidence journal,

angiocardiographic

hypertension

foremen

vasospasm

to this

adaptation

vascular

in a syndrome

to pulmonary

hearts and no radiographic In the May issue of this normal

the

infants,

results

circulation

cardiopulmonary

provided

of

some

499-504. 7. Ovitt 1W, screen-film

Circulation:

circu-

in pulmonary

shunting through patent Gersony et aI. I 21 applied fetal

Fetal

cardiopulmonary fall

closure In

response

tent night-to-left I 1 1. In 1 969, tence

postnatal

by a rapid

arteniosus.

80262

of the

AP, Hendee

examinations

8. Stables DP, Rossi AP, Caruthers SB, Anderson N: The application of newer screen-film systems to excretion urography. Am J Roentgenol 128:617-619, 1977

Center

Colorado

Persistence

Transition

M. Gilbert L. Chionis

Medical

1972

AL. Rossi

radiographic

P. Rossi

Joan Many

105:185-190,

3. Stevels ALN: New phosphors for x-ray screens. Medicamundi 20:12-22, 1975 4. Wagner RF, Weaver KE: Prospects for x-ray exposure reduction using rare-earth intensifying screens. Radiology 1 18: 183-188, 1976 5. Rossi RP, Hendee WA: An evaluation of rare-earth screenfilm combinations. Radiology 121:465-471, 1976

dose screen

significant

advances

Radiology

could

tungstate

rare-earth

1 . Rossi RP, Hendee WR, Wesenberg RL’: Reduction of patient exposure in diagnostic radiology through the use of rareearth screen-film combinations, in Operational Health Physics, Proceedings of the 9th Midyear Topical Symposium of the Health Physics Society. Denver, February 1976, pp 120-134 2. Buchanan RA, Finkelstein SI, Wickersheim KA: X-ray exposure reduction using rare-earth oxysulfide intensifying screens.

in

obvious area a presently

low

genetic

calcium

Further

use

it should

use

REFERENCES

uroradiography

next With

of reproductive

While

is at a standstill,

is only

].

Li

The

in pediatrics,

to adults.

in all children

cause from

radiography

system

system

available

various systems. has been advocated

pediatric radiography. is general radiography.

application

graphy

the

served

seen to

alert

on the