Trigeminal Nerve Blocks In Refractory Trigeminal Neuralgia: About 21 Cases Reported At The Limoges University Hospital

IntroductionDespite limited scientific evidence, trigeminal nerve blocks are alternative therapies for refractory trigeminal neuralgia (RTN). The duration of analgesia far exceeds the length of the conduction block. This study evaluated the quality of life 15 days after performing this block to treat RTN. MethodsThis retrospective study included all patients who, after informed consent, received iterative trigeminal blocks to treat a RTN between 2014 and 2018 in a university hospital. Patients received 0.5% levobupivacaine in combination with clonidine and a corticosteroid (cortivazol or betamethasone according their availability). Data were obtained from patients medical data files and a telephone questionnaire for the SF-12 score. The main criteria of evaluation was the change in quality of life according SF-12 performed at day 15. ResultsTwenty-one patients aged 62 {+/-}14 years were included. All patients exhibited RTN after many different clinical treatments according ICHD-3 criteria. Seventy-one per cent of RTN occurred after trauma or surgery. Before receiving blocks, SF-12 physical (SF12-PS) and mental (SF-12 MS) scores reached respectively 35 {+/-} 14 and 29 {+/-} 11. A mean time of 4 {+/-} 5 years elapsed between the occurrence of RTN and nerve blockade. At day 15, SF-12 PS increased by a 3 point mean value and SF-12 MS by 5 points. Approximately half of the patients (55%) were considered as non-responders with a cut-off value of less than 10% variation of their initial SF-12 score. When excluding these patients, SF-12 PS and SF-12 MS were increased by 17 and 9 points respectively. The mean duration of blocks lasted 15 {+/-} 59 days and no severe adverse effects were observed. Patient satisfaction was correlated with increased SF-12 PS (r2 = 0.3 p = 0.01) and with the length of analgesia (r2 = 0.51 p = 0.001) but not to SF-12 MS variation (p = 0.12). ConclusionTrigeminal nerve blocks are temporarily effective on pain that may increase the quality of life in responder patients. The reason why some patients are unresponsive to this treatment and why durations in efficacy are so variable remain unsolved. However, in responders, trigeminal nerve blocks seem simple, harmless, not excessively cumbersome and without severe adverse effects.