Optic Nerve Sheath Meningioma
A 21-year-old female presented at another clinic for concerns about her eyeglass prescription. She was referred to us under the impression of disc edema OS. Her best-corrected visual acuity was 6/6 in both eyes. A prism cover test showed that there was intermittent exotropia of 8 prism diopters. Slit lamp examination was normal. Disc edema with mildly tortuous retinal vessels was noted in the left eye (Fig. 10.1). There is normal vascular perfusion in early phase and mild staining on optic disc in late phase (Fig. 10.1). A slightly enlarged blind spot was noted in the patient’s left visual field (Fig. 10.2). MRI of the optic nerves revealed an increased thickness of the left optic nerve on both T1-weighted and T2-weighted images (Fig. 10.3). With gadolinium enhancement, there was a homogenous tubular enhancement along the left orbital optic nerve consistent with “tram-track sign.” On coronal view, there was a ring-shaped enhancement surrounding the optic axons called “doughnut sign” (Fig. 10.3). The patient had received eyeglass correction and has been followed with a stable visual acuity of 6/5 in both eyes for the past 4 years. During follow-up, OCT showed an increased thickness of the peripapillary retinal nerve finer layer (RNFL), which was stable for a long period (Fig. 10.4).
- 4.Miller NR, Walsh FB, Hoyt WF. Walsh and Hoyt’s clinical neuro-ophthalmology. Philadelphia: Lippincott Williams & Wilkins; 2005.Google Scholar
- 13.Metellus P, Kapoor S, Kharkar S, Batra S, Jackson JF, Kleinberg L, Miller NR, Rigamonti D. Fractionated conformal radiotherapy for management of optic nerve sheath meningiomas: long-term outcomes of tumor control and visual function at a single institution. Int J Radiat Oncol Biol Phys. 2011;80(1):185–92.CrossRefPubMedGoogle Scholar