Modifiers -LT and -RT

20.6.3 - Modifiers -LT and -RT (Rev. 11937; Issued: 03-31-23; Effective: 04-01-23; Implementation: 04-03-23) LT: Left side (used to identify procedures performed on the left side of the body) RT: Right side (used to identify procedures performed on the right side of the body) Modifiers LT and RT apply to codes that identify procedures that can be performed on paired organs, e.g., ears, eyes, nostrils, kidneys, lungs, and ovaries. These modifiers should be used whenever a procedure is performed on only one side. Hospitals should report the appropriate RT or LT modifier to identify which of the paired organs was operated upon. Do not report modifiers RT and LT when modifier 50 applies.