Help with Neuro

[canela27]

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I may be posting this in wrong section but there like no life in the med forum or people asking for content help. Please & thank you

 

[Jaa_]

break this down by localizing symptoms to cranial nerves, then by anatomy.

- double vision (diplopia) = either CN III, IV, VI or a combo
- R eye, forehead pain = V1,V2 respectively
- sluggish pupillary reaction (mediated CN II in, CNIII out), so either of these or both can be involved.
- HOWEVER vision is intact, ruling out CN II involvement.
- Right eye not moving explains the diplopia and reinforces the involvement of CN III, IV, VI
- R forehead pinprick is decreased, again implicating V1 (it worsened from pain to numbness)

So you have to find where CN III, IV, V1, V2, and VI exist at the same time, which is the superior orbital fissure (this is superior orbital fissure syndrome).

It looks like the figure is showing a superior view of the R skull base, centered at the middle cranial fossa. (A give away for the superior view vs inferior can be the perpendicular plate of the ethmoid bone visible anteriorly... in inferior view you usually see palate or maxillary dentition). Knowing this, A is the optic canal, and B is the superior orbital fissure.

This is a classic question and I can almost guarantee you will be asked a similar one in which the patient has the same symptoms WITH vision deficit, in which case the lesion is in the orbital apex (orbital apex syndrome). Or, the patient has an ipsilateral horner syndrome due to the involvement of sympathetic fibers (which are traveling along the internal carotid artery), in that case the answer is cavernous sinus syndrome. There are a lot of figures that demonstrate the differences between these syndromes on google.

BTW im having a hard time discerning CDE from the dark photo, but it looks like B is foramen rotundum... I guess C is ovale and E is spinosum? Either that or they mislabeled and the more oval shaped and posterior one is ovale and spinosum is that one adjacent to the suture line...

 

[Big Time Hoosier]

break this down by localizing symptoms to cranial nerves, then by anatomy.

- double vision (diplopia) = either CN III, IV, VI or a combo
- R eye, forehead pain = V1,V2 respectively
- sluggish pupillary reaction (mediated CN II in, CNIII out), so either of these or both can be involved.
- HOWEVER vision is intact, ruling out CN II involvement.
- Right eye not moving explains the diplopia and reinforces the involvement of CN III, IV, VI
- R forehead pinprick is decreased, again implicating V1 (it worsened from pain to numbness)

So you have to find where CN III, IV, V1, V2, and VI exist at the same time, which is the superior orbital fissure (this is superior orbital fissure syndrome).

It looks like the figure is showing a superior view of the R skull base, centered at the middle cranial fossa. (A give away for the superior view vs inferior can be the perpendicular plate of the ethmoid bone visible anteriorly... in inferior view you usually see palate or maxillary dentition). Knowing this, A is the optic canal, and B is the superior orbital fissure.

This is a classic question and I can almost guarantee you will be asked a similar one in which the patient has the same symptoms WITH vision deficit, in which case the lesion is in the orbital apex (orbital apex syndrome). Or, the patient has an ipsilateral horner syndrome due to the involvement of sympathetic fibers (which are traveling along the internal carotid artery), in that case the answer is cavernous sinus syndrome. There are a lot of figures that demonstrate the differences between these syndromes on google.

BTW im having a hard time discerning CDE from the dark photo, but it looks like B is foramen rotundum... I guess C is ovale and E is spinosum? Either that or they mislabeled and the more oval shaped and posterior one is ovale and spinosum is that one adjacent to the suture line...

Thanks for making me feel bad by reminding me about all the stuff I knew at one point and have since forgotten.

Big Hoss