Since Lance and Adams published their observations on 4 cases of post hypoxic action myoclonus in 1963, few case reports and animal studies followed, all attempted to find the best treatment and understand the pathology of the disease. In light of the rarity of the condition, no large studies were conducted. Meanwhile, because of the complexity of the pathology and the diffuse cerebral involvement, no clear guidelines regarding the treatment were established. Dysfunction in neural circuits rather than structural pathology is well documented. Several pathways were suggested. GABAA receptor activation is thought to have the most significant impact on suppression of myoclonus.
We report a case of Lance Adams Syndrome that partially responded to clonazepam pre diagnosis but now ran out of treatment. Upon presentation to neurology, clinical diagnosis was established confirmed by multi-imaging modalities while off medications. Very few studies have reported detailed clinical scaled assessment of the response to treatment. We used the unified myoclonus scale to assess the response to each medication after reaching steady state and after each dose change. Gabapentin then Valproate then clonazepam then levetriacetam were tested respectively.
Gabapentin paradoxically worsen post hypoxic myoclonus. Mutli-drug regimen had synergistic effect when compared to mono-therapy.