rsixthnervemfinal

Sixth Nerve Palsy in Pregnancy Due to Occult Intracavernous Meningioma

Michele Todman, MD

Marjorie Murphy, MD

June 18, 2010

No Financial Disclosures

Purpose

To present two cases of sixth nerve palsy presenting or worsening during pregnancy due to small intracavernous meningiomas

To our knowledge, this finding has not been previously reported

Why is this relevant to all of us?

Isolated sixth nerve palsy differential broad– vasculopathic, traumatic, elevated ICP, MS,

compressive, MG, thyroid related ophthalmopathy, isolated orbital myositis, etc.

Avoid unnecessary testing Meningiomas may grow during pregnancy MRI with attention to the cavernous sinus may be

helpful, since this entity can be easily missed in the absence of gadolinium

Methods

Two Case Reports

Case 1

40 y/o F 21st week of pregnancy Binocular horizontal diplopia and headache x 1

week Partial right 6th nerve palsy Unenhanced MRI brain/orbits reported as normal LP: normal CSF and opening pressure 3 weeks later: complete right sixth nerve palsy

Results Case 1

Figure 1: Unenhanced brain MRI of case 1 with coronal T1 image (left), and axial T2 with special attention to the cavenous sinus image (right). 17mm(AP) x 14mm(T) x 13mm(CC)

Case 2

34 y/o F Binocular horizontal diplopia and headaches x 3

weeks Partial left 6th nerve palsy MRI brain/orbits with gadolinium, LP, ACh

receptor Ab testing all normal Diplopia and sixth nerve palsy improved, nearly

resolved

Case 2

Became pregnant8th month of pregnancy: abduction deficit

worsenedMRI brain/orbits with gadolinuium

postpartum

Results Case 2

Figure 2: Gadolinium-enhanced brain MRI of case 2 with coronal T1 image (left) and axial T1(right) both with special attention tothe cavernous sinus. 10mm(AP) x 12mm(T) x10mm(CC)

Clinical Course

Cases 1 & 2 both treated with Gamma Knife radiosurgery postpartum (2 months)

Case 1: 6th nerve palsy resolved 3 months thereafter

Case 2: 6th nerve palsy persisted and patient underwent strabismus surgery

Conclusions

Meningiomas may exhibit accelerated growth during pregnancy

Cavernous sinus pathology should be considered in the Ddx of a 6th nerve palsy

Unenhanced MRI of the brain with attention to the cavernous sinus should be requested in pregnancy

Gamma knife may be deferred until after delivery