Giant Cell Arteritis Masquerading as Orbital Inflammatory Disease

Clinical Correspondence Section Editors: Robert Avery, DO Karl C. Golnik, MD Caroline Froment, MD, PhD An-Guor Wang, MD Giant Cell Arteritis Masquerading as Orbital Inflammatory Disease Jessica Y. Tong, MD, Craig James, MBBS, FRCPA, Sandy Patel, MBBS, FRANZCR, Dinesh Selva, FRACS, FRANZCO G iant cell arteritis (GCA) is a systemic vasculitic disorder with a predilection for medium- to large-sized arteries. Although orbital disease is a rare manifestation, GCA can masquerade as orbital inflammatory or ischemic syndromes (1). We present a case of GCA with a myriad of atypical features including ophthalmic artery enhancement, lacrimal gland enlargement, and an episodic stuttering sixth nerve palsy. MRI may therefore be a useful adjunctive tool for identifying orbital vasculitic changes in GCA. A 73-year-old man presented with a 4-week history of severe malaise, generalized but not proximal myalgias, and fever, associated with left orbital pain on supraduction and abduction. He denied symptoms of scalp tenderness or jaw claudication, and his systemic history was unremarkable. Examination revealed normal visual acuity, normal optic nerve function, full ocular motility, and no proptosis. There were no clinical signs of orbital inflammation or ocular ischemia. Temporal arteries were pulsatile and nontender. A full blood count demonstrated a normocytic anemia, and inflammatory markers were significantly elevated (erythrocyte sedimentation rate, ESR .100 mm/h; C-reactive protein, CRP 289 mg/L). A vasculitic screen revealed only a weakly positive antineutrophil cytoplasmic antibody (ANCA) with a classical cytoplasmic immunofluorescence pattern. An MRI (Fig. 1A–C) showed enhancement of the left optic nerve sheath and intraconal fat. The lacrimal gland was enlarged with diffuse enhancement, suggestive of generalized orbital inflammation. There was no enhancement of the lacrimal artery and no restricted diffusion. In addition, there was left greater than right enhancement of the ophthalmic arteries. A presumed diagnosis of vasculitic orbital inflammatory disease was made, and prednisolone 1 mg/kg was commenced, which resulted in a rapid clinical response within 24 hours. The patient was comanaged with Save Sight Institute, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney (JYT), Sydney, Australia; Clinpath Laboratories (CJ), Adelaide, South Australia, Australia; Department of Medical Imaging, Royal Adelaide Hospital (SP), Adelaide, South Australia, Australia; and Discipline of Ophthalmology and Visual Sciences (DS), The University of Adelaide and the South Australian Institute of Ophthalmology, Adelaide, Australia. The authors report no conflicts of interest. Address correspondence to Jessica Y. Tong, MD, Save Sight Institute, Sydney Medical School, Faculty of Medicine and Health, The University of Sydney, Sydney, 2000 Australia; E-mail: [e-mail] e242 a rheumatologist, and prednisolone was gradually tapered with normalization of inflammatory markers. Six months later, at a dosage of 8 mg, he reported intermittent horizontal diplopia, with 10 episodes occurring over a one-week period. These episodes had sudden onset and lasted 1– 2 minutes, during which it was observed that the left eye failed to abduct. Prednisolone was increased to 1 mg/kg and aspirin was commenced. His ESR had risen to 16 mm/h, although CRP remained at 7 mg/L and serial ANCA testing remained negative. A repeat MRI (Fig. 2A, B) demonstrated persistent bilateral ophthalmic artery enhancement, which may be representative of active inflammation, or residual arterial wall remodeling. Computed tomography angiography (Fig. 2C, D) confirmed bilateral critical stenosis and irregularity of the ophthalmic arteries, with sparing of the temporal artery and external carotid branches. Given the onset of an atypical stuttering diplopia and radiologic features of ophthalmic arteritis, the clinical suspicion for GCA was high. A left temporal artery biopsy was performed, which revealed focal fragmentation and calcification of the internal elastic lamina, intimal hyperplasia with myxoid degeneration, and periadventitial lymphocytic infiltration. Overall, the histological appearance demonstrated resolving inflammatory changes consistent with partially healed or treatment-modified temporal arteritis. Methotrexate was added to the treatment regimen, and then switched to tocilizumab. At 2-month follow-up, the patient had no disease recurrence. We describe an unusual case of GCA that presented as orbital inflammatory disease. MRI studies provided valuable insight into orbital vasculitic changes, which included ophthalmic artery enhancement, clinically occult optic nerve sheath enhancement, and lacrimal gland enlargement. The development of a stuttering sixth nerve palsy also represented an intermittent claudication of ocular motility. High-resolution MRI is a useful adjunctive technique for detecting intracranial vasculitis in GCA (2). The ophthalmic and posterior ciliary arteries are some of the most commonly and severely affected vessels in GCA (3). Ophthalmic artery stenosis and enhancement may also provide evidence of vasculitis. The incidence in GCA is reported to be 46%–76%, but this cannot be precisely determined, given that orbital imaging is not routinely performed (2,3). Geiger et al retrospectively analyzed high-resolution MRIs in 43 patients with Tong et al: J Neuro-Ophthalmol 2023; 43: e242-e244 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence FIG. 1. MRI at initial presentation. Postcontrast T1 fat-suppressed sequences reveal left orbital inflammatory changes. There is more left than right ophthalmic artery enhancement (A–B, arrows). In addition, the sequences demonstrate enhancement of the left optic nerve sheath (A) and left lacrimal gland (C, arrowhead). The left inferior rectus seems edematous (A), but the relatively flattened appearance of the right inferior rectus is also due to artifact. GCA, of which 20 (46%) demonstrated ophthalmic artery enhancement, a finding that was often associated with mural thickening (2). The segment crossing the optic nerve was most commonly involved. Although there is no known association between the degree of enhancement and disease activity, ophthalmic artery enhancement is likely an underrecognized sign in GCA and can provide useful adjunctive evidence of orbital vasculitis. Radiologic studies of orbital GCA extend beyond analysis of vascular supply. In our patient, additional MRI features were enhancement of the intraconal fat and optic nerve sheath. Similarly, reported features of GCA have included ill-defined enhancement of the optic nerve pathway (parenchyma, sheath, and/or chiasm) and retrobulbar fat (1,4). High signal intensity and enhancement of the optic nerve can be associated with anterior ischemic optic neuropathy, but may also be clinically silent as demonstrated in our case (5). Another unique feature in our case was lacrimal gland enlargement and enhancement. With partial corticosteroid treatment, there was resolution of these radiologic findings on repeat MRI. To the best of our knowledge, lacrimal gland changes have only been described in one other case report by FIG. 2. MRI orbital scans performed 6 months later reveal persistent bilateral ophthalmic artery enhancement (A–B, arrows), suggestive of ophthalmic arteritis. On computed tomography angiography, the right ophthalmic artery is critically stenosed at its origin (C, arrowhead). Similarly, there is stenosis of the left ophthalmic artery, which appears narrow and irregular just beyond its origin (D, arrowhead). Tong et al: J Neuro-Ophthalmol 2023; 43: e242-e244 e243 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited. Clinical Correspondence Heraud et al (5), whereby a patient with GCA presented with unilateral proptosis, lacrimal gland enlargement, and restricted diffusion. A scan repeated 1 month later revealed normalization of the diffusion signal, with new enhancement of the lacrimal and temporal arteries. The authors postulated that restricted diffusion of the lacrimal gland was due to ischemia from lacrimal artery inflammation and vascular compromise. Although our case did not feature lacrimal gland restricted diffusion or lacrimal gland artery enhancement, radiologic findings of dacryoadenitis in combination with GCA symptoms and ophthalmic artery enhancement were suggestive of an atypical orbital inflammation. Ophthalmoplegia in GCA is not uncommon, as arteritic involvement of the ophthalmic artery and/or its branches compromises vascular supply to the extraocular muscles. Although patients in the GCA demographic are more likely to have microvascular risk factors, the transient stuttering nature of the motility disorder was indicative of significant arterial insufficiency. This case highlights the diverse orbital manifestations of GCA and the utility of neuroimaging in identifying vasculitic changes. Development of a claudication-like motility disorder was indicative of ongoing vascular compromise within the orbit. Judicious assessment of clinicor- e244 adiological features and consideration of temporal artery biopsy is paramount. STATEMENT OF AUTHORSHIP Conception and design: D. Selva. Acquisition of data: J. Y. Tong, C. James, S. Patel, D. Selva. Analysis and interpretation of data: J. Y. Tong, C. James, S. Patel, D. Selva. Drafting the manuscript: J. Y. Tong, C. James, S. Patel, D. Selva. Revising the manuscript for intellectual content: J. Y. Tong, C. James, S. Patel, D. Selva. Final approval of the completed manuscript: J. Y. Tong, C. James, S. Patel, D. Selva. REFERENCES 1. Lee AG, Tang RA, Feldon SE, Pless M, Schiffman JS, Rubin RM, Rao N. Orbital presentations of giant cell arteritis. Graefes Arch Clin Exp Ophthalmol. 2001;239:509–513. 2. Geiger J, Ness T, Uhl M, Lagrèze WA, Vaith P, Langer M, Bley TA. Involvement of the ophthalmic artery in giant cell arteritis visualized by 3T MRI. Rheumatology (Oxford). 2009;48:537– 541. 3. Wilkinson IM, Russell RW. Arteries of the head and neck in giant cell arteritis. A pathological study to show the pattern of arterial involvement. Arch Neurol. 1972;27:378–391. 4. D’Souza NM, Morgan ML, Almarzouqi SJ, Lee AG. Magnetic resonance imaging findings in giant cell arteritis. Eye (Lond). 2016;30:758–762. 5. Heraud A, Zmuda M, Lecler A. Lacrimal gland ischemia due to giant cell arteritis. Ophthalmology. 2018;125:1233. Tong et al: J Neuro-Ophthalmol 2023; 43: e242-e244 Copyright © North American Neuro-Ophthalmology Society. Unauthorized reproduction of this article is prohibited.