Ultrastructural study of extraocular muscle tendon axonal profiles in infantile and intermittent exotropia

Seung Hyun Kim, Sung Tae Yi, Yoonae A. Cho, Chang Sub Uhm

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Purpose: To investigate the ultrastructures of tendon axonal profiles in infantile and intermittent exotropia. Tendon axonal profiles are composed of myotendinous nerve endings that are presumed to serve as sensorial receptors in ocular proprioception. Methods: The study subjects included 10 patients with exotropia who had undergone surgery in one eye (recession and resection). They were divided into two equal groups. Five patients with infantile exotropia that had developed at under 12 months of age were allocated to group A. Another five, with intermittent exotropia that had developed at over 12 months of age, were allocated to group B. In all patients, medial recti were resected by 3-4 mm in order to obtain tissue samples, which were then examined under an electron microscope. Results: In group A, we noted many axonal degenerative findings, such as the retraction of axons from myelin sheaths with considerable shrinkage, axonal disintegration, and Schwann cell proliferation. On the other hand, we identified three unique findings in group B: intact axons with incomplete Schwann cell wrapping; intact Schwann cells not associated with axons, and disorganized Schwann cells with shrunken axons. Conclusion: Different patterns of tendon axonal profiles were seen in association with the two types of exotropia. These differences may be related to the pathogenesis of these exotropia types.

Original languageEnglish
Pages (from-to)182-187
Number of pages6
JournalActa Ophthalmologica Scandinavica
Volume84
Issue number2
DOIs
Publication statusPublished - 2006 Apr 1

Fingerprint

Oculomotor Muscles
Exotropia
Tendons
Schwann Cells
Axons
Proprioception
Nerve Endings
Myelin Sheath
Cell Proliferation
Electrons

Keywords

  • Axonal degeneration
  • Infantile exotropia
  • Intermittent exotropia
  • Ocular proprioception
  • Schwann cell degeneration
  • Tendon axonal profiles

ASJC Scopus subject areas

  • Ophthalmology

Cite this

Ultrastructural study of extraocular muscle tendon axonal profiles in infantile and intermittent exotropia. / Kim, Seung Hyun; Yi, Sung Tae; Cho, Yoonae A.; Uhm, Chang Sub.

In: Acta Ophthalmologica Scandinavica, Vol. 84, No. 2, 01.04.2006, p. 182-187.

Research output: Contribution to journalArticle

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