Botulinum toxin A injection for chronic anal fissures and anal sphincter spasm improves quality of life in recessive dystrophic epidermolysis bullosa oleh Cassandra Chaptini, MBBS, Genevieve Casey, MBBS, Adam G. Harris, MBChB, David Wattchow, FRACS, Lynne Gordon, FACD, Dedee F. Murrell, MA, BMBCh, FAAD, MD, FACD, FRCP