Impact of Glabellar Paralysis on Facial Expression of Emotion.

BACKGROUND: Many prospective patients remain wary of the effects that glabellar muscle paralysis may have on their ability to normally communicate emotion with their face. OBJECTIVE: We undertook a direct empirical test of the effects of glabellar onabotulinum toxin type A injections on the ability to convey 6 universally recognized facial expressions of emotion. METHODS: Fifty-two female subjects ("expressors") were recorded on hidden camera while viewing video clips intended as a mood induction procedure that stimulates the 6 cardinal emotions (amusement, anger, disgust, fear, sadness, surprise). The subjects were then injected with 25 units of onabotulinum toxin A in the glabellar region. The subjects returned 1 month later and were again recorded while being spontaneously induced to express emotion. All video clips from both time periods from the 10 maximal expressors were extracted and shown to a group of 31 "perceivers" who rated the facial expressions for intensity (Likert 1-7) and identity of emotion (percent correct emotion identified). RESULTS: Glabellar paralysis significantly diminished mean perceived intensity of anger (50.4% relative reduction, P < 0.001) and surprise (20.6% relative reduction, P < 0.001). The mean intensity of disgust increased (39.0%, P < 0.001). Importantly, however, glabellar paralysis did not result in a significant change in observers' ability to discern provoked cardinal emotions. CONCLUSIONS: We believe these findings provide a measure of reassurance to patients and their providers that the use of onabotulinum toxin A to paralyze the glabellar musculature for aesthetic purposes may not pose a meaningful risk to the overall ability to express emotion during social interaction.

The Frequency of Carpal Tunnel Syndrome in Hurler Syndrome After Peritransplant Enzyme Replacement Therapy: A Retrospective Comparison.

PURPOSE: Children with Hurler syndrome (HS) develop carpal tunnel syndrome (CTS) owing to glycosaminoglycan deposition secondary to enzyme deficiency. Advancement in the treatment of the underlying enzyme deficiency now commonly includes peritransplant intravenous enzyme replacement therapy (ERT). The primary objective of this study was to determine if the use of limited ERT in addition to hematopoietic stem cell transplantation (HCT) for the treatment of children with HS reduces the incidence of surgical intervention for CTS compared with a cohort of historical controls treated with HCT alone. The secondary objectives were to evaluate the impact of demographic and transplant-related characteristics on the incidence of CTS. Lastly, the results of surgical treatment of CTS in HS are reported. METHODS: Medical records for a historical group of 43 HS patients who underwent HCT alone (group 1) were compared with 31 HS patients who underwent HCT + ERT (group 2). Both groups were compared for genotype, age at transplant, sex, transplant graft source, median/ulnar nerve conduction study parameters as well as the incidence and treatment of CTS. Pre- and postoperative nerve conduction studies were compared for children treated surgically for CTS. RESULTS: The cumulative incidence of CTS at 5 years for HS children treated with HCT + ERT was 51% compared with 47% for HS children treated with HCT alone. The incidence of CTS did not depend upon graft source, age at transplant, or sex. Median nerve conduction velocity for both sensory and motor potentials demonstrated significant improvement after carpal tunnel release. CONCLUSIONS: Although the administration of ERT prior to and for several months after HCT has become routine in our institution, our findings do not suggest this combined therapy is sufficient to decrease the development of CTS. Surgical intervention for median nerve compression remains the treatment of choice for CTS in HS children. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic IV.