Giant cell arteritis (GCA) can present with atypical presentations that are diagnostically challenging.

An 84-year-old woman with a history of breast adenocarcinoma treated with lumpectomy and radiation 2 years prior presented with a seizure-like episode. She reported a few months of fatigue and developed a right-sided headache and pain while chewing 2 weeks prior. Soon thereafter, her right upper eyelid became ptotic. Examination showed 20/20 vision in each eye, a slightly larger right pupil, right upper lid ptosis, and a deficit of elevation, depression, and adduction of the right eye (Figure 1A). Ocular exam was normal otherwise. Her erythrocyte sedimentation rate and C-reactive protein were 68 mm/h (ref 0-20) and 12.7 mg/dL (ref ≤ 0.5), respectively. She was diagnosed with a right pupil-involving cranial nerve (CN) III palsy; magnetic resonance angiography of the head was negative for a circle of Willis aneurysm. Brain magnetic resonance imaging (MRI) showed bilateral optic nerve sheath and orbital enhancement (Figure 1B). She was prescribed 60 mg prednisone daily. A temporal artery biopsy revealed granulomatous arteritis consistent with GCA. Given her carcinoma history, the optic nerve sheath and orbital enhancement raised concerns for orbital metastasis. She underwent a right lateral orbitotomy, with biopsy of the atypical orbital fat and optic nerve sheath. Pathology revealed chronic granulomatous inflammation without malignancy (Figure 2). Her symptoms improved and she was transitioned to tocilizumab. Six weeks later, her CN III palsy resolved and a repeat MRI demonstrated improvement of the orbital enhancement.

(A) Extraocular motility photographs demonstrate the inability to elevate and adduct the right eye. The right upper eyelid is ptotic and a cotton swab was used to elevate the eyelid. The relative dilation of the right pupil is not visible in these images. (B) Gadolinium-enhanced axial T1-weighted brain magnetic resonance imaging with fat suppression demonstrates irregular enhancement of both optic nerve sheaths and orbits (white arrows).

Photomicrograph of orbital tissue with elastic stain demonstrates the presence of epithelioid histiocytes (black arrowhead), consistent with granulomatous inflammation. A small fragment of internal elastic lamina is present (white arrowhead), consistent with granulomatous arteritis (Verhoeff Van Gieson stain; original magnification 200×). Pathology images courtesy of Nasreen Syed, MD.

CN palsies are uncommon in GCA1-3; orbital and optic nerve sheath enhancement are even rarer.4,5 Awareness of atypical presentations is critical to preventing treatment delay.

The authors acknowledge an unrestricted grant from Research to Prevent Blindness to the University of Iowa Department of Ophthalmology and Visual Sciences. The authors declare no conflicts of interest relevant to this article. This report is in accordance with the 2013 Helsinki Declaration, and written consent to publish identifying information, including photographs, was obtained from the patient. Photographs were taken with proper authorization.