The pon's is the top part of the brain stem, yes the Pon's is involved in facial nerves (trigeminal nerve, abducens nerve, facial nerve, vestibulocochlear nerve), cranial nerves V, VI, VII and VIII are at the border of the pons.
There is a 'potential' explanation but keep in mind that they often don't know exactly what causes bells palsy, there's a high association to herpes simplex and diabetes as well as other's......lesion-symptom mapping is very difficult to get absolutely 100% right!
Having a Pon's lesion and periventricular lesions will definitely limit the list of potential medical explanations in your age group, MS unfortunately will be on your list but deep breath cause it still may not be MS...
Hope that helps.......JJ
Hi. This is more a question for anyone knowledgeable than an informed comment, but here goes------
You mention that your Bell's Palsy has occurred both times on the right. Also that your MRI shows a small lesion in the left pons. I know that outside the brain, functions etc., are controlled by nerves on the opposite side, to be crude about a much more complicated issue. But in the brain or head itself, I don't think the 'opposite effect' applies. If this is true, then the left pons lesion would not be the cause of the right side palsy. Not to say you do or don't have MS nonetheless, as I certainly don't know, but just suggesting the BP may be an extra issue of unknown causation.
On the other hand, my idea may be totally wrong. Could you ask your neuro about this?
Best of luck.
hmmmm would you like fry's with that :D there's often no simple answer that's for sure.....i can't accurately answer ess's opposite effect, i was thinking along similar lines whilst i was posting. When it comes to the Pon's i'm not 100% sure the opposite applies either, it's a central location, it's quite small compared to other parts of the brain approx 2.5 cm long, it's basically the bridge between various parts of the nervous system.
I'm more use to research that's separated the Pon's into upper, mid or lower areas but I still couldn't find anything research related that isolated the Pon's lesion specifics to which side of the face would likely be affected, which was surprising. The best I could come up with was a Pon's lesion was a 'potential' explanation but there was lot's of factors that effects IF it could be the more likely than any other potential, so it's a maybe yes, maybe no which is as clear as mud..
Bell's palsy is associated with lower motor neural track but upper motor neuron facial palsy causes slightly different signs, so the question i've got in my head is could you actually raise both your eyebrows or was the entire right side including the right eyebrow palsy?
Tutorials explaining the differences between umn and lmn look to me like there is an opposite going on with facial palsy but at this stage i'm starting to get too loopy lala :D so i could be a tad backwards lol
check out https://www.youtube.com/watch?v=5T4G27xkckE to get an easy easy understanding of umn vs lmn to get an idea..
Hope that helps and not confuses you more.....JJ
I'm still curious about how all this works, even though I lack even a basic understanding of cranial nerves. But according to Wikipedia, that paragon of accuracy :-)
"Lesions of the facial nerve (VII) may manifest as facial palsy. This is where a person is unable to move the muscles on one or both sides of their face. A very common and generally temporarily facial palsy is known as Bell's palsy. Bell's Palsy is the result of an idiopathic (unknown), unilateral lower motor neuron lesion of the facial nerve and is characterized by an inability to move the ipsilateral muscles of facial expression, including elevation of the eyebrow and furrowing of the forehead. Patients with Bell's palsy often have a drooping mouth on the affected side and often have trouble chewing because the buccinator muscle is affected."
The significant word above is 'ipsilateral,' which I learned means 'same-sided.' If, and this is a big if, I have this right, then a lesion on the left pons would not be the cause of right Bell's Palsy. However, some cranial nerves apparently do affect the opposite side, and the nerves leave the brain and the skull at various points. All this is beyond my ken.
I do plan to ask my neuro about this idea generally because of my history of trigeminal neuralgia, which has been on the right. I have at least one pons lesion, but the radiologist's language is fuzzy, something about 'right more than left,' which hardly clarifies things for this question. In any case, no pons lesion has ever enhanced on my MRIs (nor has any lesion anywhere), yet I have a brain full of lesions and definite MS.
Bottom line for me: Go figure.