Morphologic Cross-Sectional Imaging Features of IgG4-Related Orbitopathy in Comparison to Ocular Adnexal Lymphoma

Abstract

Aim To detect radiological features that, in addition to clinical findings, may aid in correct differentiation between IgG4-related ophthalmic disease (IgG4-ROD) and ocular adnexal lymphoma (OAL). Methods In this retrospective, single-center, comparative analysis, we compared cross-sectional imaging findings of 13 consecutive patients with histologically proven IgG4-ROD and a control group of 29 consecutive OAL-patients diagnosed between 10/2014 and 09/2019. Statistical significance was accepted at a p <0.05 significance level. Results IgG4-ROD-patients had longer time-to-diagnosis, higher orbital recurrence rates, but smaller lesions compared to OAL-patients ( p =0.002; p =0.006 and p =0.006; Mann–Whitney U -test). Frequent cross-sectional imaging findings in both IgG4-ROD-patients and OAL-patients included extraocular muscle enlargement (92% and 93%, respectively; most often in the lateral rectus muscles and the levator-complex), and lacrimal-gland enlargement (85% and 83%, respectively). Other imaging findings comprised infraorbital nerve-involvement (IgG4-ROD, 23%, OAL, 17%) and orbital fat inflammation (IgG4-ROD, 23%, OAL, 28%). Bony infiltration and remodeling, heterogenous contrast-media distribution, and infiltration of the lacrimal system were seen slightly more often in IgG4-ROD (23%, 38%, 15% and 15% versus 17%, 14%, 3% and 7%). However, cross-sectional imaging features did not differ significantly between patient subgroups. Clinical symptoms predominantly occurred unilaterally (IgG4-ROD, 9/13, 69%, OAL, 24/29, 83%), while imaging findings were most often bilateral (IgG4-ROD, 11/13, 85%, OAL, 23/29, 79%, p <0.001, McNemar test). Conclusion No morphological cross-sectional imaging sign could reliably distinguish between IgG4-ROD and OAL, leaving histopathology indispensable for definite diagnosis. Yet, importantly, for both IgG4-ROD and OAL, cross-sectional imaging frequently detected bilateral orbital disease when only one eye was clinically affected.

Radiological Determinants of Complicated Immunoglobulin G4–Related Ophthalmic Disease: A Territory-Wide Cohort Study

“…44% of our patients presented with isolated lacrimal gland enlargement, which was comparable to 48% in the Japanese cohort reported by Sogabe et al 7 In contrast, EOM was reported as the most common site of involvement in 1 European cohort. 22 Forty-one of 115 (36%) of our patients had enlarged EOM, and only 9/41 (22%) of them suffered from diplopia, similar to previous reports. 7,23,24 IONE was associated with IgG4-ROD 9 and reactive lymphoid hyperplasia, 10 and it was found in 27% of our patients.…”

“…The lacrimal gland was the most frequently involved in 90% of our patients, similar to the Japanese,7,19 Korean,20 and American21 studies. 44% of our patients presented with isolated lacrimal gland enlargement, which was comparable to 48% in the Japanese cohort reported by Sogabe et al7 In contrast, EOM was reported as the most common site of involvement in 1 European cohort 22. Forty-one of 115 (36%) of our patients had enlarged EOM, and only 9/41 (22%) of them suffered from diplopia, similar to previous reports 7,23,24.…”

“…2,12,13 Both IgG4-ROD and IgG4-ROL affect the lacrimal glands. Klingenstein et al 22 reported that there is no radiological difference between these 2 conditions, and it is impossible to differentiate the 2 entities clinically. Yuan et al 38 reported that orbital lymphoma was more commonly unilateral and showed molding features radiologically when compared with Ig-G4-ROD.…”

IgG4-Related Disease

“…41 However, another study in German patients did not find any CT imaging differences between both diseases. 42 An imaging finding highly suggestive of IgG4-ROD is the involvement of the trigeminal nerve branches, especially the infraorbital nerve (Fig. 3C), which has not been found in GO, orbital lymphoma, reactive lymphoid hyperplasia, idiopathic orbital inflammation, or adult xanthogranulomatous disease.…”

Orbital Muscle Enlargement: What if It’s Not Graves’ Disease?

“…Primary extraocular muscle lymphomas are rare, it accounts for about 0.1% and 8.7% of all extranodal lymphomas [24,25]. In most cases extraocular muscle involvement is due to infiltration of extramuscular masses [26,27].…”