[Music]
so there are three different major
techniques that are used with chest
x-rays let's take a look at each one so
we have inspiration penetration and
rotation and each of these can change
the appearance of the chest so this is
an example of an expert or a film versus
an inspiratory film when a chest x-ray
is obtained you really want to obtain it
in optimum inspiration so that means
about eight to nine posterior ribs
should be visible so taking a look at
this inspiratory film here the way you
count the posterior ribs is this so the
ribs that are seen best are the ones
that are posterior these are the ribs
that are right here and you want to
start from the top and just count all
the way down to the bottom a low
inspiration results in crowding of the
lung markings so as you compare this
expert ory film versus the inspiratory
film you can see that there is crowding
of the lung markings the lung volumes
look actually a lot lower on the expert
Tori film than they do on the
inspiratory film and everything because
of that just looks very hazy so
oftentimes it's difficult to detect an
abnormality on a patient that doesn't
have a good inspiration penetration is
another technical factor so the film on
the Left is over penetrated while the
film on the right is under penetrated
penetration refers to the amount of
x-rays that are passing through the area
that's being evaluated and penetration
can differ based on patient body type so
if a patient if a film is over
penetrated that means everything will
appear very dark and that can mimic
abnormalities such as a pneumothorax
which we'll discuss later if a film is
under penetrated then everything will
look very white and that can make it
very difficult to actually see what's
going on in the lungs rotation is
another technical factor if a patient is
rotated the mediastinum and hilum turned
towards the side of rotation and they
appear larger on that side which can
mimic a mass so this is an example of
three different types of rotation the
first one is normal the middle one
represents a patient that's rotated to
the right
and the last one represents a patient
that's rotated to the left so to tell
whether a patient is rotated or not the
easiest way is to look at the medial
ends of the clavicles and they really
should be equidistant from the spinous
process so let's take a look here on
this first film here is the medial end
of the right clavicle and here is the
medial end of the left clavicle if you
look right in the midline here these are
the spinous processes so you want to be
equidistant from the spinous processes
which this one is and this is the
typical view that we would want to
obtain the film in if a patient is
rotated to the right you have more space
between the right clavicle and the
spinous process then you do between the
spinous process and the left clavicle so
you can see here it almost looks like
there's a little bit of a mass that's
projecting on this side and that's
really just the mediastinal structures
that are turning towards the side of
rotation similar to a patient that's
rotated on the Left where there's more
space between the left clavicle and the
spinous process than there is between
the right clavicle and the spinous
process so it's important to develop a
normal algorithm to take a look at a
chest radiograph this is important in
all of radiology for every imaging study
that you look at you want to have a
normal algorithm so that you ensure that
you look at every single structure
that's present on the film so this is an
algorithm that I use when looking at a
chest x-ray I first take a look at any
abnormal tubes lines and foreign objects
patients that are in the hospital may
have multiple different lines and tubes
that are placed within them and you want
to make sure that you look at all of
these and to ensure that they're in
satisfactory position I then take a look
at the lungs I next look at the airway
that includes the trachea and the
bronchi you want to take a look at all
of the mediastinal boundaries and make
sure that they look normal without the
presence of any mass I then take a look
at all of the surrounding soft tissues
including the soft tissues of the
shoulders the neck and the chest I take
a look at the bony structures and you
can see multiple ribs you can see
clavicles you can often see the
shoulders as well on a chest radiograph
and then lastly I take a look at the
upper abdomen although we don't see a
very large portion of the upper abdomen
we do see a small
and it's important to make sure that if
there are any abnormalities we see them
on the chest radiograph
[Music]
you