Abstract
Injections of botulinum toxin type A (BoTox) in one extraocular muscle (EOM) induce long lasting paretic lengthening of the muscle permitting realignment to occur in strabismus, while eye movements appear to be unaffected after the transitory period of induced paresis. It has been hypothesized a BoTox-induced change in the spindle discharge of EOMs to explain the effect in EOM length. In decerebrate lambs and goats, first order neurons of eye muscle spindles were identified in a cellular pool located in the medial dorsolateral portion of the semilunar ganglion. The belly of the muscle to which the recorded unit belonged was infiltrated with BoTox. A decrease in afferent discharge of the spindle and in its stretch sensitivity was observed. This effect began 10–15 minutes after the injection. There was no corresponding decrease in muscle tension during the first 45 minutes. This finding suggests that the block of release of acetylcholine at motor endings is earlier and more efficacious in γ- than in α-motoneurons. As a result of the proprioceptive input reduction, an unbalance between the agonist and antagonist muscles should occur favouring the ocular realignment.
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References
Barmack NH. Laminar organization of the extraocular muscles of the rabbit. Exp Neurol 1978; 59: 304–21
Barmack NH, Errico P, Ferraresi A, Pettorossi VE. Interactions of cervico-ocular and vestibulo-ocular fast phase signals in the control of eye position in rabbits. J Physiol 1989; 410: 213–25.
Bortolami R, Lucchi ML, Pettorossi VE, Callegari E, Manni E. Localization and somatotopy of sensory cells innervating the extraocular muscles of lamb, pig and cat. Histochemical and electrophysiological investigation. Arch Ital Biol 1987; 125: 1–15
Browne JS. The responses of muscle spindles in sheep extraocular muscles. J Physiol 1975; 251: 483–96
Cull-Candy SG, Lundh G, Thesleff S. Effects of Botulinum toxin on neuromuscular transmission in the rat. J Physiol 1976; 260: 177–203
Duchen LW. An electron microscopic study of the changes induced by botulinum toxin in the motor end plates of slow and fast muscle fibres of the mouse. J Neurol Sci 1971; 144: 47–60
Duchen LW. Changes in the electron microscopic structure of slow and fast skeletal muscle fibres of the mouse after local injection of botulinum toxin. J Neurol Sci 1971; 14: 60–74
Elston JS, Lee JP, Powell CM, Hogg C, Clark P. Treatment of strabismus in adults with botulinum toxin A. Br J Ophthal 1985; 69: 718–24
Elston JS, Ross Russell R. Effect of treatment with botulinum toxin on neurogenic blepharospasm. Br Med J (Clin Res) 1985; 290: 1857–9
Frueh BR, Felt DP, Wojno TH, Musch DC. Treatment of blepharospasm with botulinum toxin. Arch Opthal 1984; 102: 1464–8
Harker DW. The structure and innervation of sheep superior rectus and levator palpebrae extraocular muscles. II. Muscle spindles. Invest Ophthal 1972; 11: 970–9
Kao I, Drachman DB, Price DL. Botulinum toxin: mechanism of presynaptic blockade. Science 1976; 193: 1256–8
Keller EL, Robinson DA. Absence of a stretch reflex in extraocular muscles of the monkey. J Neurophysiol 1971; 34: 908–19
Kubota M. Ultrastructural observations on muscle spindles in extraocular muscles of pig. Anat Anz Jena 1988; 165: 205–28
Magoon EH. Botulinum toxin chemo-denervation for strabismus in infants and children. J Pediatr Ophthal Strabismus 1984; 21: 110–2
Maier A, De Santis M, Eldred E. The occurrence of muscle spindles in extraocular muscles of various vertebrates. J Morph 1974; 143: 397–408
Manni E, Bortolami R, Desole C. Eye muscle proprioception and the semilunar ganglion. Exp Neurol 1966; 16: 226–36
Manni E, Bortolami R, Desole C. Peripheral pathway of eye muscle proprioception. Exp Neurol 1968; 22: 1–12
Manni E, Bortolami R, Deriu PL. Presence of cell bodies of the afferents from the eye muscles in the semilunar ganglion. Arch Ital Biol 1970; 108: 106–20
Manni E, Pettorossi VE. Somatotopic localization of the eye muscle afferents in the semilunar ganglion. Arch Ital Biol 1976; 114: 178–87
Manni E, Pettorossi VE, Errico P. Botulinum toxin and eye muscle proprioceptive input. Neuro-Ophthalmology Congress abstracts CEMS-24, Vancouver B.C. 1988
Mauriello JA. Blepharospasm, Meige syndrome and hemifacial spasm: treatment with botulinum toxin. Neurology 1985; 35: 1499–1500
Molgo' J, Thesleff S. Studies on the mode of action of botulinum toxin type A at the frog neuromuscular junction. Brain Res 1984; 297: 309–16
Pettorossi VE, Filippi GM. Muscle spindle autogenetic inhibition in the extraocular muscles of lamb. Arch Ital Biol 1981; 119: 179–94
Porter JD, Spencer RF. Localization and morphology of cat extraocular muscle afferent neurons identified by retrograde transport of horseradish peroxidase. J Comp Neurol 1982; 204: 56–64
Scott AB, Rosenbaum AL, Collins CC. Pharmacological weakening of extraocular muscles. Invest Ophthal 1973; 2: 924–7
Scott AB. Botulinum toxin injection into extraocular muscles as an alternative to strabismus surgery. J Pediatr Ophthal Strabismus 1980; 17: 21–5
Scott AB, Kennedy RA, Stubbs HA. Botulinum A toxin injection as a treatment for blepharospasm. Arch Ophthal 1985; 103: 347–50
Schaaf P. Muskelspindeln in den äußeren Augenmuskeln der Vertebraten. In:Drischel H, Kirmse W (eds) Das okulomotorische System, physiologische und klinische Aspekte. VEB Georg Thieme, Leipzig 1979; pp 173–180
Spencer RF, McNeer KW. Adaptive morphological changes in monkey extraocular muscle following botulinum toxin paralysis. ARVO abstract 9, Invest Ophthal Vis Sci 1987; 28(3) Suppl: 153
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Manni, E., Bagolini, B., Pettorossi, V.E. et al. Effect of botulinum toxin on extraocular muscle proprioception. Doc Ophthalmol 72, 189–198 (1989). https://doi.org/10.1007/BF00156709
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DOI: https://doi.org/10.1007/BF00156709