4-46. FILM HOLDERS AND GRIDS
a. General. The choice of film holders can play an important role in the quality
of the finished radiograph made by portable examination. SR, as it affects film quality,
must also be considered when examinations are not limited to small parts, the chest, or
other areas where SR is not a problem.
b. Film Holders. As a general rule, portable equipment examinations should be
done using screen technique. One reason for this is that minimum exposure times are
possible when using intensifying screens. Since patients involved in these
examinations are frequently not able to cooperate by remaining motionless, fast
exposure times can be a valuable asset in improving the clarity of the radiograph.
Another reason cassettes are advantageous is mAs required for non-screen exposures
might exceed the capacity of the unit. Finally, cassettes can better withstand the weight
involved in some portable equipment examination.
c. Grids. Grids (either portable or grid cassettes) should be used for all
examinations where SR might pose a problem. An unfocused grid is recommended for
general use because you frequently are unable to use the SID required by a focused
grid. This is not to say that a focused grid cannot be used. On the contrary, these will
produce excellent results when you are able to determine the SID ahead of time and
bring the proper grid. For general use, however, when the exact circumstances are not
known beforehand, an unfocused or parallel grid should be used.
a. It is difficult to establish definite procedures for bedside examinations
because of the unpredictable conditions of patients. A procedure that works perfectly
for one patient may not work for another. Therefore, the x-ray specialist must decide
upon the best course of action depending on the circumstances. Some common sense
rules, however, will apply in most cases.
b. It is good practice, when the patient's condition permits, to go into the room
and introduce yourself to the patient before bringing in the portable unit. At this time,
ensure you have the correct patient by checking the armband or by checking with the
nurses' station. The abrupt entrance of an x-ray specialist propelling a large, strange
machine may alarm some patients unless they have been told to expect this.
c. If intravenous (IV) fluids are being administered, use care in preparing the
patient and the bed for the examination. Rough handling of either may cause the
needle to dislodge from the vein and the fluid to infiltrate the surrounding tissue. Be
extra careful with other devices that may be in use--suction apparatus, traction device,
and so forth.