Purchase this article with an account.
Laurel Tainsh, Syed Amal Hussnain, Amy Yuan, Anshu Shukla, Michael Ehrlich; MRI quantification of intraconal fat volume in patients with Idiopathic Intracranial Hypertension. Invest. Ophthalmol. Vis. Sci. 2017;58(8):3312.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Idiopathic intracranial hypertension (IIH) is a syndrome of increased intracranial pressure with unknown etiology that is most common in obese women of childbearing age. Methods to accurately predict the severity of visual loss on neuroimaging are lacking and measurement of intraconal fat volume in patients with IIH has not been described. We performed a retrospective chart review to estimate intraconal fat volume and its association with BMI and vision in patients with IIH.
The charts from all patients with an ICD code of IIH in epic at Yale New Haven Hospital from 2010-2015 were reviewed for this study. Patients with age ≥18 years, a lumbar puncture with opening pressure >20cm water, MRI of orbits and brain, and ophthalmic exam between 2010-2015 were included. Patients were excluded if not meeting Dandy Criteria for IIH or for incomplete data. Intraconal fat was estimated by subtracting the volume of the optic nerve from the total intraconal volume on measurements from coronal T1 weighted MRI scans. Data was analyzed via linear regression.
We identified 526 patients with an ICD code for IIH. Of these, 25 patients (50 eyes) were included. Mean intraconal fat volume was 1.98 cm3 (range 1.30 – 2.61 cm3). Mean BMI was 38.8 kg/m2 (range 25.3-51 kg/m2). Vision ranged from 20/20 to light perception only. 23/25 (92%) of patients were female with average age 36 yrs (range 18-61 yrs). On linear regression analysis, there was a positive correlation between intraconal fat volume and BMI (slope=0.03 ± 0.006, R2=0.30, p=0.0001), but no correlation between intraconal volume and BCVA.
Intraconal fat volume varies in patients with IIH and is positively correlated with BMI. The association between intraconal fat volume and visual outcomes remains unclear. Future work will identify patients in which measurements of intraconal fat volume might predict visual outcomes and potential benefit from early intervention.
This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.
This PDF is available to Subscribers Only