Perilymph penetration of methotrexate in cats

The perilymph of the inner ear has recently been suggested as a site of frequent leukemic or lymphomatous infiltrates. Experimental evidence supports the existence of barrier mechanisms and explains the attenuated entry of several substances, including chemotherapeutic agents, from either the cerebrospinal fluid or blood into the perilymph. The present study describes the attenuated entry of methotrexate into the perilymph compartment of experimental animals following intrathecal or iv administration.