Muscle biopsy substantiates long-term MRI alterations one year after a single dose of botulinum toxin injected into the lateral gastrocnemius muscle of healthy volunteers.

Abstract

Despite numerous clinical and experimental studies on botulinum toxin type A (BoNT/A), long-term alterations of muscle texture and fine structure following BoNT/A treatment have thus far not been studied in normal human skeletal muscle. After obtaining institutional review board approval, we performed a prospective, placebo-controlled, double-blinded follow-up study on two healthy adults using magnetic resonance imaging (MRI) and muscle biopsy to visualize long-term alterations after a single BoNT/A injection into the lateral head of the gastrocnemius muscle. MRI disclosed a high-signal-intensity pattern in short tau inversion recovery sequences, and a reduction of the cross-sectional area in the BoNT/A-injected, but not in the saline-injected contralateral control muscle (at 6 to 9 months in volunteer A: 73%, in B: 62%; at 12 months in A: 88%, and in B: 78%). Enzyme histochemistry, 12 months after injection, confirmed neurogenic atrophy of muscle fibers only in the BoNT/A-injected muscle. Electron microscopy revealed additional degenerative changes at the neuromuscular junction. The data confirm that MRI is a suitable tool to monitor the long-term effect of BoNT/A on skeletal muscle. Neurogenic muscle atrophy following a single BoNT/A injection should be taken into consideration when repeated BoNT/A injections into the same muscles are proposed.

• Authors: A Sebastian Schroeder, Birgit Ertl-Wagner, Stefanie Britsch, J Michael Schröder, Stefan Nikolin, Joachim Weis, Wolfgang Müller-Felber, Inga Koerte, Maximilian Stehr, Steffen Berweck, Ingo Borggraefe, Florian Heinen
• Journal: Movement disorders : official journal of the Movement Disorder Society (Mov Disord) Vol. 24 Issue 10 Pg. 1494-503 (Jul 30 2009) ISSN: 1531-8257 [Electronic] United States
• PMID: 19489066 (Publication Type: Clinical Trial, Journal Article)
• Copyright: Copyright 2009 Movement Disorder Society.

Chemical References

• Anti-Dyskinesia Agents
• Botulinum Toxins

Topics

• Adult
• Anti-Dyskinesia Agents (pharmacology)
• Biopsy (methods)
• Botulinum Toxins (pharmacology)
• Double-Blind Method
• Humans
• Magnetic Resonance Imaging (methods)
• Male
• Microscopy, Electron, Transmission (methods)
• Middle Aged
• Muscle, Skeletal (anatomy & histology, drug effects, ultrastructure)
• Prospective Studies