To report a case where bilateral malignant retrobulbar lymphoma was diagnosed after repetitive intraocular lens dislocation to the anterior chamber.

An 85-year-old male with a history of stroke who had undergone cataract surgery 10 years ago at another hospital presented with repeated intraocular lens (IOL) dislocations of both eyes into the anterior chamber. He had previously undergone IOL scleral fixation once in his left eye and twice in his right eye, but IOL dislocation was still repeatedly occurring. The best-corrected visual acuity was 0.4 in both eyes. Hertel exophthalmetry was 20 mm in his right eye and 18 mm in his left eye. Painless limitation of motion at supraduction was observed in the right eye. Funduscopy showed newly appeared choroidal folding in the right eye, so orbital computed tomography (CT) with contrast was performed. The CT scans showed bilateral homogenously enhancing retrobulbar masses. Biopsy of the masses showed a MALToma. After radiation therapy, the choroidal folds resolved and exophthalmetry improved to 10 mm in both eyes. No additional IOL dislocation occurred. During 2.5 years of follow-up, there was no evidence of recurrence or distant metastasis of the MALToma.

Orbital lymphomas can cause lid edema, exophthalmos, strabismus, and diplopia, and can be diagnosed with imaging modalities such as CT. Final diagnosis involves biopsy and radiation therapy or chemotherapy. If IOL dislocation occurs repeatedly, it may result from an increase in retrobulbar pressure, and concurrent choroidal folding using funduscopy is strongly recommended for imaging to check for the presence of retrobulbar masses.