Magnetic Resonance Imaging and Keratopigmentation: A Systematic Review and Ex Vivo Study of Complications and Adverse...

To evaluate the safety of magnetic resonance imaging (MRI) in patients who have previously undergone keratopigmentation, with particular attention to the potential adverse effects associated with different types of tattoo inks.

Various colored and black tattoo inks were tested under MRI conditions. In vitro analysis was conducted to assess ink mobility. Ex vivo porcine and rabbit eyes were used to evaluate macroscopic changes, MRI artifact formation, and histological modifications after exposure to the magnetic field.

No adverse effects or visible artifacts were observed with iron oxide-free inks during MRI. In contrast, inks containing iron oxide produced artifacts that significantly inhibited eye analysis without affecting posterior structures. Under normal MRI conditions, histological examination revealed subtle pigment migration with iron oxide-based inks; a finding not observed with other ink types. Under supranormal exposure, pigment migration was pronounced, readily visible both macroscopically and histologically.

MRI appears safe in patients with keratopigmentation using iron oxide-free inks, which are the most commonly used. In contrast, iron oxide-containing inks can induce MRI artifacts that inhibit ocular assessment without affecting brain visualization. Under the influence of the magnetic field, their pigments may also migrate, potentially causing ocular pain, central corneal involvement, or weakening of corneal biomechanical integrity. For corneal tattooing, we recommend using carbon-based inks for black pigmentation and one of the iron oxide-free inks for colored keratopigmentation.