Oman Journal of Ophthalmology

CLINICAL IMAGE
Year
: 2022  |  Volume : 15  |  Issue : 2  |  Page : 252--254

Idiopathic intracranial hypertension sine disc edema with rare neuroimaging features of cranial nerve compression


Goura Chattannavar1, Jenil Nilesh Sheth2, Dandu Ravi Varma3, Ramesh Kekunnaya4,  
1 Clinical Fellow, Academy for Eye Care Education, L. V. Prasad Eye Institute, KAR Campus, Hyderabad, Telangana, India
2 Clinical Faculty, Child Sight Institute, L. V. Prasad Eye Institute, KAR Campus, Hyderabad, Telangana, India
3 Citi Neuro Centre, Jasti V. Ramanamma Children Eye Care Center, L. V. Prasad Eye Institute, KAR Campus, Hyderabad, Telangana, India
4 Child Sight Institute, Jasti V. Ramanamma Children Eye Care Center, L. V. Prasad Eye Institute, KAR Campus, Hyderabad, Telangana, India

Correspondence Address:
Dr. Jenil Nilesh Sheth
Clinical Faculty, Child Sight Institute, Jasti V Ramanamma Children's Eye Care Centre, L.V. Prasad Eye Institute, Kallam Anji Reddy Campus, L.V. Prasad Marg, Banjara Hills, Hyderabad 500034, Telangana
India

Abstract




How to cite this article:
Chattannavar G, Sheth JN, Varma DR, Kekunnaya R. Idiopathic intracranial hypertension sine disc edema with rare neuroimaging features of cranial nerve compression.Oman J Ophthalmol 2022;15:252-254


How to cite this URL:
Chattannavar G, Sheth JN, Varma DR, Kekunnaya R. Idiopathic intracranial hypertension sine disc edema with rare neuroimaging features of cranial nerve compression. Oman J Ophthalmol [serial online] 2022 [cited 2022 Oct 6 ];15:252-254
Available from: https://www.ojoonline.org/text.asp?2022/15/2/252/348984


Full Text



Idiopathic intracranial hypertension (IIH) without papilledema is a known entity with a prevalence of 5%–14% in patients with chronic headache.[1] There is very limited literature on meningoceles of craniomotor nerves in IIH. We report a rare and an interesting neuroimaging of craniomotor meningoceles in a case of IIH without papilledema.

A 41-year-old woman of African descent, morbidly obese in built presented with a progressive inward deviation of the left eye [Figure 1] for 7 years with occasional diplopia, associated with holocranial tension type of headache and pulsatile tinnitus. She gave no history of transient visual obscurations. Her best-corrected visual acuity was 20/20, N6 in both the eyes. Her color vision was normal. Ocular motility showed marked limitation of abduction in the left eye with large-angle esotropia in the primary gaze [Figure 1]. There was no involvement of other cranial nerves. Pupillary reflexes were normal, and optic discs were healthy [Figure 2] in both eyes. Humphrey's visual fields did not show any neurological field defect on the gray scale. Given long-standing non-resolving left sixth cranial nerve palsy with chronic headache, magnetic resonance imaging (MRI) of the brain and orbit with contrast and MR venogram (MRV) were advised.{Figure 1}{Figure 2}

T2-weighted(T2W) MRI showed posterior flattening of globes, enlarged perioptic space, and empty sella, and MRV revealed stenosis of the junction of transverse sigmoid sinus [Figure 3]a, [Figure 3]b, [Figure 3]c, [Figure 3]d. To our surprise, the patient also had enlarged cerebrospinal fluid (CSF) spaces around oculomotor [Figure 4]c and [Figure 4]d and abducens nerve [Figure 5]a, [Figure 5]b, [Figure 5]c, [Figure 5]d on either side. There was also CSF expansion along the glossopharyngeal nerves [Figure 4]a as well as distention of Meckel's cave [Figure 4]b. There was no hyperintensity along the meninges of the cranial nerves or elsewhere [Figure 3]e, [Figure 3]f, [Figure 3]g. A lumbar puncture was done which revealed CSF opening pressure of 43 cms of water with normal CSF analysis. Even in the absence of papilledema, our patient fulfilled the criteria of IIH without papilledema proposed by Friedman and Jacobson.[2] The patient was advised weight loss and oral acetazolamide 2 g/day in divided doses with potassium supplements. During the follow-up period of 3 months, our patient subjectively felt better; however, there was no improvement in left-sided sixth cranial nerve palsy.{Figure 3}{Figure 4}{Figure 5}

We believe that the lack of papilledema even in the presence of raised intracranial pressure can be attributed to the size of the optic canal diameter and possibly due to the redistribution of CSF more around craniomotor nerves than optic nerves. Meningoceles and enlargement of Meckel's cave have been reported in the literature as an additional imaging sign in IIH.[3] San Millán and Kohler have reported three cases of IIH with enlarged CSF spaces around oculomotor and abducens nerve and enlargement of Meckel's cave.[3],[4] Similarly, our patient also had enlarged subarachnoid CSF spaces around oculomotor, abducens, and glossopharyngeal nerves. The CSF space around abducens nerve is enlarged throughout its course from cisternal segment to cavernous sinus, more localized on the left side compared to the right side, explaining the compressive left-sided sixth cranial nerve palsy. These findings give one step further insight into our understanding of pathophysiology of IIH. Craniomotor meningoceles in the absence of papilledema should be considered an additional imaging sign in IIH.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1Vieira DS, Masruha MR, Gonçalves AL, Zukerman E, Senne Soares CA, Naffah-Mazzacoratti Mda G, et al. Idiopathic intracranial hypertension with and without papilloedema in a consecutive series of patients with chronic migraine. Cephalalgia 2008;28:609-13.
2Friedman DI, Jacobson DM. Diagnostic criteria for idiopathic intracranial hypertension. Neurology 2002;59:1492-5.
3Bialer OY, Rueda MP, Bruce BB, Newman NJ, Biousse V, Saindane AM. Meningoceles in idiopathic intracranial hypertension. AJR Am J Roentgenol 2014;202:608-13.
4San Millán D, Kohler R. Enlarged CSF spaces in pseudotumor cerebri. AJR Am J Roentgenol 2014;203:W457-8.