BTK and B-cell chronic lymphocytic leukemia: Furthermore, recurrent bleeding or even isolated bleeding in ophthalmological patients with CLL or undergoing treatment with BTK inhibitors or similar medication with mutagenic effect should always be suspect for ocular malignancy and warrant imagistic investigations such as UBM which provides a high-resolution view of the angle and posterior iris surface, or mode B ultrasound for posterior pole examination through opaque media such as cataracts.