The Greater Petrosal Nerve
HIDEInteractive Transcript
0:00
Dr. P here talking about the reater petrosal nerve,
0:03
a branch of the facial nerve.
0:07
It's an important nerve,
0:08
but it's one that doesn't get a lot of attention.
0:10
It arises at a locus where the geniculate ganglion
0:14
provides a marker.
0:15
So here's your geniculate ganglion right there.
0:17
And here is the curve,
0:19
the genu of the facial nerve right there.
0:21
It's hard to see the curve,
0:22
but I'll draw it so you can fantasize it,
0:25
and I'm going to put a little color on it.
0:28
And then coming forward in an oblique fashion
0:31
is the greater petrosal nerve.
0:33
Now, there's some high signal here
0:34
because there's a petrosal plexus of slow flowing vessels
0:39
right there, that contribute to that hyper,
0:42
or apparent hyperintensity.
0:44
The greater petrosal nerve provides parasympathetic
0:47
innervation to several glands, including nasal glands,
0:50
palatine glands, the lacrimal gland,
0:52
and the pharyngeal gland.
0:54
It also provides parasympathetic innervation to the
0:57
sphenoid sinus, the frontal sinus, the maxillary sinus,
1:01
the ethmoid sinus, and the nasal cavity.
1:03
This is an important nerve.
1:05
It also has taste fibers for the lesser palatine nerve
1:09
and the palate, and also the greater palatine nerve.
1:12
It contributes to the otic ganglion,
1:14
and it arises again at the level
1:16
of the geniculate ganglion,
1:17
where it joins the lesser petrosal nerve
1:20
to reach the otic ganglion.
1:22
In the sagittal projection,
1:23
if you want to find that nerve,
1:24
you can just cross reference.
1:26
Let's take our little cross reference marker right here.
1:29
There is our geniculate area right there,
1:32
and just in front of it,
1:33
you're going to find the greater petrosal nerve.
1:35
So right there is going to be the greater petrosal nerve,
1:38
which again,
1:38
is slightly hyperintense for reasons
1:41
we already mentioned.
1:41
Dr. P out.
Stephen J Pomeranz, MD
Chief Medical Officer, ProScan Imaging. Founder, MRI Online
ProScan Imaging
© 2024 MRI Online. All Rights Reserved.