Owandy I-Max Touch, Руководство пользователя

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USER'S MANUAL
General instructions for use
I-Max Touch (110-120V) (Rev. 0) 118
This is not true, because it is derived from the projection
geometry used to obtain the panoramic image. The effect can be
more evident if the image in underexposed due to wrong
radiological parameters.
With reference to Figure 28 above, let’s analyse some errors.
•
Wrong positioning of the spine
In the event the image shows an over-bright and unfocused part in
the central area (see point "4" - Figure 28), this is probably caused by
the wrong position of the spine that has not been properly extended
by the patient. In this case, the spine absorbs an excessive quantity
of radiation that therefore causes the image to be over-bright. This
excessive brightness can be seen above all in the lower part, but is
less visible in the upper part of the X-ray.
Solution:
Ask the patient to step forward, thus extending his spine, in order to
reduce X-ray absorption.
•
Shadows or bright artefacts
The most common cause for the presence of these artefacts is the
presence of metal objects worn by the patient (earrings, necklaces,
etc.).
The necklaces worn by the patient normally result in a radio-opaque
arch positioned in the chin area. This arch normally overlaps the
chin itself and the shadow of the spine, disturbing the diagnosis of
possible problems in the chin area and in the area of the apices of
the mandibular incisors.
The earrings, on the other hand, create real images in the proper
position and shadow images projected in the contro-lateral area, thus
hiding possible problems or generating bright areas within the
paranasal sinuses.
In some cases, that may depend either on the trajectory of the
panoramic machine or on the position of the metal objects, they can
generate up to three images (one real and two shadows), thus further
disturbing the correct diagnosis.
This situation may occur especially if the patient has large prosthesis
or metal fillings, and is associated with a positioning error, that
projects the shadow of the metal part on wide areas of the image.