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.

Keywords:

• IgG4
• idiopathic orbital inflammation
• CT
• ocular adnexal lymphoma

Abbreviations

ADC, apparent diffusion coefficient; AJCC, American Joint Committee on Cancer; ANOVA, analysis of variance; AP, anterior-posterior; BCL, B-cell-lymphoma; BCVA, best corrected visual acuity; CC, craniocaudal; CD, cluster of differentiation; CISH, chromogenic in situ hybridization; CT, computed tomography; DWI, diffusion-weighted MRI-imaging; ENMZL, extranodal marginal zone lymphoma; IgG4-ROD, IgG4-related ophthalmic disease; LR, lateral; MALT, mucosa-associated lymphoid tissue; MRI, magnetic resonance imaging; OAL, ocular adnexal lymphoma; PACS, picture-archiving-and-communication system; PAS, periodic acid-schiff; RAPD, relative afferent pupillary defect; V, tumor volume estimate.

Data Sharing Statement

The blinded datasets used and analyzed during the current study are available from the corresponding author upon reasonable request.

Ethics Approval and Consent to Participate

The study was waived by the ethics committee of Ludwig-Maximilians-University, Munich, Germany (project number 20-633 KB), giving their “declaration of no objection” and approving “no consulting obligation” regarding the retrospective evaluation of clinical and radiographic patient data of patients suffering from orbital lesions. All patients gave informed consent for cross-sectional imaging examination. All patient data is non-identifiable and complied with relevant data protection and privacy regulation.

Consent for Publication

Not applicable, no identifiable images included.

Author Contributions

All authors made substantial contributions to conception and design, acquisition of data, or analysis and interpretation of data; took part in drafting the article or revising it critically for important intellectual content; agreed to submit to the current journal; gave final approval of the version to be published; and agree to be accountable for all aspects of the work.

Disclosure

The authors report no conflicts of interest in this work.

Additional information

Funding

The authors did not receive support from any organization for the submitted work.