text: The I isotope is also used as a radioactive label for certain radiopharmaceuticals that can be used for therapy, e.g. I-metaiodobenzylguanidine (I-MIBG) for imaging and treating pheochromocytoma and neuroblastoma. In all of these therapeutic uses, I destroys tissue by short-range beta radiation. About 90% of its radiation damage to tissue is via beta radiation, and the rest occurs via its gamma radiation (at a longer distance from the radioisotope). It can be seen in diagnostic scans after its use as therapy, because I is also a gamma-emitter.