Background/aims To evaluate CT and MRI findings of histopathologically proven ocular adnexa IgG4-related disease.

Methods Study subjects included 18 patients with histopathologically proven ocular adnexal IgG4-related disease. CT (n=16) and MR (n=3) images were retrospectively evaluated for location, laterality, shape, margin, attenuation on precontrast CT images, T1 and T2 signal intensity on precontrast MRI , internal architecture, ocular adnexal lesion enhancement patterns, sialadenitis of major salivary glands, cervical lymph node enlargement and perilesional bony change.

Results Lacrimal gland enlargement was observed in 16 cases. Extraglandular lesions were observed in the medial canthus (n=2) and extraconal space (n=2). Bilateral supraorbital and infraorbital nerves, pterygopalatine fossa and cavernous sinus involvement were observed in one case. All ocular adnexal lesions showed well defined margins, isoattenuation on precontrast CT images, isointensity on T1- and hypointensity on T2-weighted images, homogenous internal arcithecture and enhancement patterns and bone remodelling without destruction.

Conclusions Ocular adnexal IgG4-related disease can involve the lacrimal gland, medial canthus, extraconal space, supraorbital and infraorbital nerves, pterygopalatine fossa and cavernous sinus. A diagnosis of ocular adnexal IgG4-related disease should be considered in lesions with the typical imaging features described herein.