Treatment of emotional lability in ALS

Emotional Lability as a Symptom of Extra-axial Posterior Fossa Tumors: a Case-Control Review of Neuroanatomy and Patient-Reported Quality of Life

Introduction  Emotional lability (EL), the uncontrollable and unmotivated expression of emotion, is a rare and distressing symptom of brainstem compression. In published case reports, EL from an extra-axial posterior fossa tumor was alleviated by tumor resection. The primary aim herein was to radiographically establish the degree of compression from mass lesions onto brainstem structures. Secondarily, we compared changes in patient-reported quality of life (QOL) pre- and postoperatively. Methods  A retrospective review of posterior fossa tumors treated between 2002 and 2018 at Vancouver General Hospital revealed 11 patients with confirmed EL. Each case was matched to three controls. A lateral brainstem compression scale characterized mass effect at the level of the medulla, pons, and midbrain in preoperative axial T2-weighted fluid-attenuated inversion recovery magnetic resonance imaging (FLAIR MRI) scans. Compression and clinical variables were compared between patient groups. Short Form-36 version 1 health surveys were retrospectively obtained from patient charts to compare pre- versus postoperative changes in survey scores between EL and control patients. Results  EL symptoms ceased postoperatively for all EL patients. EL tumors exert greater compression onto the pons ( p  = 0.03) and EL patients more commonly have cerebellar findings preoperatively ( p  = 0.003). Patients with EL-causing tumors experienced greater improvement postoperatively in "Health Change" ( p  = 0.05), which was maintained over time. Conclusion  Findings suggest that compression onto the pons inhibits control over involuntary, stereotyped expression of emotion. This adds to evidence that EL may be attributed to cerebellum deafferentation from cortical and limbic structures through the basis pontis, leading to impaired modulation of emotional response. QOL results augment benefits of offering patients EL-alleviating tumor resection surgery.

Dextromethorphan/quinidine: a novel dextromethorphan product for the treatment of emotional lability

Dextromethorphan (DM) is among the most widely used, non-narcotic antitussives, with a predictable safety profile. In 1981, a non-opioid, high-affinity brain recognition site for DM was discovered, and since then a unique neuropharmacological profile has emerged for this 'old' drug , suggesting novel applications. However, an extensive body of research for DM alone in treating various neurological conditions has been inconsistent. This may be largely due to its rapid first-pass metabolism. DM is currently being reintroduced as the active ingredient in a novel combination product in which low-dose quinidine is added to inhibit its breakdown, elevating blood levels of DM and increasing its likelihood of reaching neuronal targets . This has opened new possibilities for therapeutic use; the best evidence at present being for neurological disorders affecting emotional control.