Sclerotherapy with bleomycin does not adversely affect facial nerve function in children with cervicofacial cystic lymphatic malformation

Abstract Background and Purpose Sclerotherapy with bleomycin sulfate (BS) is currently used in the management of cervicofacial cystic lymphatic malformations in children. Neurotoxic adverse effects of BS after intraventricular or intracavitary administration have been reported; however, the effects of intralesionally administered BS on the adjacent peripheral neural structures have not been previously investigated. The authors conducted a clinical experimental study to evaluate facial nerve function in children who have undergone BS sclerotherapy for cervicofacial cystic lymphatic malformation. Materials and Methods Twelve patients who underwent BS sclerotherapy for cervicofacial lymphatic malformation were included in the study. The hospital records were reviewed, and the following data were recorded: age at admission and at the time of motor nerve conduction study (MNCS) and electromyography (EMG) study, sex, time elapsed between sclerotherapy and the EMG study, and the outcome. The MNCS/EMG study was performed by neurologists blinded to the side of sclerotherapy. Bilateral facial MNCS and needle-EMG study of the orbicularis oris muscle on the treated side were performed. The previously treated and untreated sides constituted the study and control groups, respectively. In the MNCS, compound muscle action potential (CMAP) amplitude and distal latencies were recorded from the orbicularis oculi and orbicularis oris muscles on both sides, and needle-EMG of the orbicularis oris muscle was performed on the treated side. Results The male-to-female ratio was 2, and age at the time of sclerotherapy ranged from 1 month to 16 years (median, 19.5 months). The lymphatic malformations were located in the right submandibular (n = 5), left submandibular (n = 6), and in the right buccal (n = 1) areas. Bleomycin sulfate was injected 1 to 4 times, and the time elapsed between injections varied from 1 to 6 months. The results of sclerotherapy were excellent, with residual disease observed in only 1 patient. The MNCS/EMG study was performed 6 months to 10 years after completion of sclerotherapy, and ages of the patients at the time of the study ranged from 4 to 17 years. Side-to-side CMAP amplitude difference did not exceed 50% for orbicularis oculi and orbicularis oris muscles. The mean CMAP amplitude of orbicularis oculi and orbicularis oris muscles on the treated and untreated sides (1219.0 ± 842.0 vs 1202.4 ± 923.8 μ V and 1866.3 ± 911.5 vs 1921.0 ± 910.0 μ V, respective