Extraocular muscles differ from most other skeletal muscles in terms of constituent fiber types and innervation pattern. The rules that govern fiber responses to various experimental interventions for most skeletal muscles, therefore, may not strictly apply to the extraocular muscles. In this study, denervation of the extraocular muscles of Cynomolgous monkeys, Macaca fascicularis, was accompli...

Extraocular muscle is fundamentally distinct from other skeletal muscles. Here, we review the biological organization of the extraocular muscles with the intent of understanding this novel muscle group in the context of oculomotor system function. The specific objectives of this review are threefold. The first objective is to understand the anatomic arrangement of the extraocular muscles and th...

Proptosis and diplopia due to enlargement of extraocular muscles represent important presenting signs of many orbital disorders. Although dysthyroid ophthalmopathy is the most common cause of enlargement of extraocular muscles, the differential diagnosis is extensive. We report a patient with a 3-month history of diplopia and unilateral proptosis and a markedly enlarged inferior rectus muscle o...

BACKGROUND Congenital fibrosis of extraocular muscles (CFEOM) is a very rare congenital condition, characterized by variable amounts of restriction of the extraocular muscles, with or without ptosis. The aim of this report was to describe a severe, atypical, exposure-induced corneal stromal lysis in two patients. CASE REPORT A mother and a daughter with a severe CFEOM were presented. The surg...

Purpose: To introduce an advanced muscle hook to decrease risks and create more feasible extraocular muscle surgeries for physicians. Case Report: Tight extraocular muscles during strabismus surgery could be extremely challenging even in experienced hands due to restricted globe rotation, limited view, and lack of muscle elasticity. Although a variety of surgical instruments have been introduce...

E. lye movements may be divided grossly into "tonic" and "phasic" movements. Are both of these principal types produced by the same motor nerves and muscle fibers, or are separate systems present that are functionally suited to each of the types of movements? Morphological and physiological studies demonstrate that at least two and possibly three neuromuscular systems are present in eye muscles...

The purpose of this study is to determine the effect of the extraocular muscles on the response of the eye under static and dynamic loading conditions. Two different types of tests have been performed. First, static displacement tests were conducted utilizing computed tomography to visualize the displacement of the eye within the orbit. Six eyes were tested in situ in matched pairs, one eye wit...

PURPOSE We examined the utility of near-resonance saturation pulse imaging (magnetization transfer [MT] and spin lock) in characterizing microstructural changes occurring in the extraocular muscles of patients with thyroid-related ophthalmopathy (TRO). METHODS Eight healthy volunteers and 10 patients with TRO were imaged using an off-resonance saturation pulse in conjunction with conventional...

Extraocular muscles are characterized by their faster rates of contraction and their higher resistance to fatigue relative to limb skeletal muscles. Another often reported characteristic of extraocular muscles is that they generate lower specific forces (sP(o), force per muscle cross-sectional area, kN/m(2)) than limb skeletal muscles. To investigate this perplexing issue, the isometric contrac...

PURPOSE Our goal was to determine whether the extraocular muscles in patients with chronic progressive external ophthalmoplegia (CPEO) could be distinguished from those of age-matched control subjects by MR imaging. METHODS Nine patients with CPEO and eight age-matched healthy control subjects were studied. The extraocular muscles of eight of the patients (16 eyes) and all the control subject...