00:01
The sphenoid bone
is very complicated and has
lots of different parts.
00:06
We'll start with the
centrally located body.
00:10
To which we have
small projections
called the lesser wings.
00:15
And then larger projections
called the greater wings.
00:19
Running more inferiorly
are these processes called
the pterygoid processes.
00:26
If we look at the body,
especially its anterior surface,
we can see a little sphenoid
crest in the midline.
00:33
And apertures for
the sphenoid sinus.
00:36
The spheroid sinus being one
of the pair of nasal sinuses
that exists within
the sphenoid bone.
00:43
We also see the inferior surface
and lateral surfaces here.
00:50
And if we swing around, we
see the posterior surface.
00:54
And this is going to interact
with the occipital bone.
00:59
Here we see the
superior surface.
01:02
And it has structures such
as the jugum sphenoidale.
01:06
And part of the clivus,
the smooth part that's going
towards the occipital bone.
01:12
And then there's a little groove
called the chiasmatic groove.
01:16
Where we have the optic chiasm.
01:18
And this is where
the optic nerves
sort of crossover before
becoming the optic tracts.
01:25
And this region is known
as the sella turcica,
because of its resemblance
to a Turkish horse saddle.
01:32
And it has a little depression
called the tuberculum sellae.
01:37
And the dorsum sellae.
01:39
And together they're
going to form
this hypophysial fossa.
01:43
Which is going to be the space in
which the pituitary gland sits.
01:50
Now we see the
larger projections
the greater wings
sticking out laterally.
01:56
And here we have the
various surfaces.
02:00
And openings of the greater wing
of the sphenoid bone.
02:04
First we see the
foramen rotundum.
02:08
And the more oval
shaped foramen ovale.
02:12
We also have a smaller one
called the foramen spinosum.
02:19
Here we see laterally
the temporal portion
or the temporal surface
of the sphenoid bone.
02:27
And in here we see
the orbital surface
from an anterior point of view.
02:33
And from this point of view,
we can see another opening
and this is the optic canal.
02:38
Which is the opening
for the optic nerves.
02:41
Between the lesser and greater
wings is a much larger opening
called the superior
orbital fissure.
02:46
Through which multiple cranial
nerves are going to pass.
02:53
Hanging down inferiorly
from the sphenoid bone
are the pterygoid
processes or plates.
03:01
We have a medial plate.
03:03
And a lateral plate.
03:05
And in between is
the pterygoid fossa.