Biomedical subjects
Publications and source records attributed to M Flanders.
Strabismus developed in eight patients following scleral buckling procedures for retinal detachment. The factors involved in the pathogenesis of the strabismus and the surgical techniques used to realign the eyes are described in this paper.
Two patients with oculocutaneous albinism who had presumed sensory-defect nystagmus also showed the features of congenital motor-defect nystagmus. Both patients used an abnormal head posture to block the nystagmus, and each had coexisting strabismus. Modern surgical techniques simultaneously shifted the null point of the nystagmus to the primary position and corrected the strabismus.
The results of conventional strabismus surgery are always somewhat uncertain, despite the most careful preoperative assessment. Yet it is important to achieve good alignment in patients with fusion potential who have intermittent exotropia, extraocular muscle paresis or a restrictive syndrome. Planning surgery for patients with thyroid myopathy and planning reoperations is particularly difficult. In 30 patients with various strabismus disorders the use of adjustable sutures proved safe and of value; the results were unacceptable in only 5 of the 28 patients with horizontal deviations. The inconvenience for the surgeon and the extra discomfort for the patient seemed outweighed by the predictability of the surgical result.
BACKGROUND: In the healing phase of thyroid-related orbitopathy, fibrosis and contracture of the extraocular muscles may result in restrictive ocular motility. Ocular misalignment may occur in both eyes and along three different axes of rotation. Successful surgical treatment depends on precise identification of the muscles that are restricting motility and producing the misalignment. METHODS: Between 1980 and 1994, 22 patients were surgically treated for restrictive strabismus caused by thyroid-related orbitopathy. Preoperatively, all patients underwent complete neuroophthalmic, oculoplastic, and orthoptic examinations. Analysis of ductions, measurement of torsion, and the use of monocular neutralization techniques were essential additions to the usual motility exam. Patients were placed into diagnostic categories based on the clinical pattern of extraocular muscle restriction. Adjustable recessions were done for all initial surgeries. RESULTS: Patients with unilateral inferior rectus involvement or with ipsilateral inferior rectus-contralateral superior rectus involvement had large vertical deviations (equal to or > 20 prism diopters [delta]). Patients with bilateral inferior rectus involvement had small vertical deviations (< 20 delta). Excyclotorsion correlated strongly with the presence of tight inferior recti. Vertical comitance (upgaze versus downgaze measurement of equal to or < 15 delta) correlated with the ipsilateral inferior rectus-contralateral superior rectus pattern of involvement. Vertical incomitance (upgaze versus downgaze measurement of > 15 delta) correlated with unilateral inferior rectus involvement. Eighteen of 22 patients had excellent postoperative alignment and elimination of diplopia in functional positions of gaze. Those with less favorable results developed reversal of the hypertropia and exotropia in downgaze. Sixteen out of 19 patients who underwent inferior rectus recession had induced inferior eyelid retraction. CONCLUSION: Different combinations of extraocular muscle restriction in this series of patients produced characteristic patterns of misalignment. Appropriate, adjustable, strabismus surgery was successful in restoring binocular vision in 21 out of 22 patients with a minimum of complications.