Michael Flanders

Diagnosis and surgical management of strabismus associated with thyroid-related orbitopathy

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.

Herpes Simplex Keratitis and Amblyopia

Herpes simplex keratitis can cause severe loss of vision in children. The findings in five children show that amblyopia is caused by stimulus deprivation and/or anisometropia. Early medical treatment, occlusion therapy, and frequent refractions are crucial for a good visual prognosis.

Masked bilateral superior oblique palsy

BACKGROUND A diagnosis of masked bilateral superior oblique palsy (MBSOP) is established when signs of SOP appear in the normal eye of a patient after strabismus surgery for SOP in the contralateral eye. Despite the absence of signs of bilaterality before surgery, a palsy will develop in the previously unaffected eye in 10% or more of the patients undergoing surgery. This paper examines the clinical profiles and results of surgical management of 14 patients with MBSOP. METHODS We retrospectively analysed the records of all 14 patients with the clinical criteria for MBSOP in the clinical strabismus database of patients treated by the second author between 1979 and 2001. We extracted the history and data from the pre- and postoperative ophthalmic and orthoptic examinations, recorded the surgical procedures and tabulated the postoperative results. The surgical outcome was considered successful if normal head posture was restored, diplopia was eliminated in functional positions of gaze, and ocular alignment was improved to within 5 prism dioptres (PD) of orthotropia. RESULTS All 14 patients had presented with seemingly unilateral SOP. The average primary-position hypertropia preoperatively was 17 (range 4-30) PD. The mean excyclotorsion was 5 degrees (n = 12). Most patients (93%) had a head tilt, mild V pattern, moderate inferior oblique overaction and mild superior oblique underaction. Initial surgery consisted of ipsilateral inferior oblique weakening with or without contralateral inferior rectus recession. The average primary-position hypertropia after the first operation (n = 14) was 8 (range 0-15) PD. In the previously masked eye inferior oblique overaction averaged +1.8 and superior oblique underaction -1.1. The average interval from initial surgery to involvement of the contralateral side was 14.9 (range 0.2-52) weeks. The average primary-position hypertropia after the second operation (n = 10) was 1.6 (range 0-10) PD; follow-up averaged 15 (range 0-120) months. Postoperative alignment was excellent (within 6 PD of orthotropia) and binocular vision restored in 9 of the 10 patients. INTERPRETATION Masked superior oblique palsy is difficult to detect before surgical correction of the initially manifest palsy. However, the possibility of an occult contralateral palsy should be considered in all patients undergoing surgery for unilateral SOP. Patients should be informed preoperatively of the possibility of this outcome. When the masked palsy becomes evident, a successful surgical outcome can usually be expected.

Partial third cranial nerve palsy: clinical characteristics and surgical management.

PURPOSE Incomplete recovery from injury to the third cranial nerve results in ocular misalignment and associated diplopia. Our aim in this study was to describe and evaluate strabismus surgery strategies aimed at restoring functional, single binocular vision in this population. DESIGN Retrospective review. PARTICIPANTS We studied 12 adult patients with acquired partial third cranial nerve palsy who underwent strabismus surgery. METHODS The 12 consecutive patients with residual third nerve palsy were selected from among the patients seen between 2000 and 2010 in the clinical practice of 1 strabismologist (M.F.). Complete pre- and postoperative ophthalmologic and orthoptic examinations were performed in each patient. The patients presented with isolated hypotropias (n = 7) and exohypotropias (n = 5). Strabismus surgery included: contralateral superior rectus recession, ipsilateral inferior rectus recession, vertical transposition of horizontal recti, horizontal rectus muscle surgery, or combined horizontal and vertical muscle surgery. Complete surgical success was defined as postoperative alignment within 5 prism diopters (PD) of orthotropia and the absence of diplopia in functional positions of gaze. The average follow-up was 23 months (range, 7 to 81 months). RESULTS The mean preoperative vertical and horizontal deviations were 19 PD hypotropia (8-40 PD) and 19 PD exotropia (6-40 PD), respectively. The mean postoperative deviations were 2 PD hypotropia (0-8 PD) and 1 PD exotropia (0-6 PD). Complete surgical success was achieved in 7 of 12 patients. Partial success was attained in 5 of 12 patients, who experienced significant improvement but required postoperative use of a prism. CONCLUSIONS This study indicates that patients with incomplete third cranial nerve paralysis may enjoy good functional and cosmetic outcomes with strabismus surgery.

Surgical Management of Unilateral Superior Oblique Palsy: Thirty Years of Experience

Introduction and Purpose We describe the clinical characteristics of 252 patients with unilateral superior oblique palsy who underwent strabismus surgery. We assess if a predetermined surgical strategy, based on preoperative alignment and motility measurements, was effective in treating these patients. On this basis, the patients were divided into three different treatment groups. Methods Two-hundred fifty-two patients were identified retrospectively and classified into three groups according to the performed procedures: 1) inferior oblique weakening; 2) inferior rectus recession; 3) combined inferior oblique weakening and inferior rectus recession. Demographic and clinical data were recorded. Criteria for surgical success included good postoperative alignment (distance, primary position alignment ≤5Δ), and improvement of diplopia and of abnormal head posture. Subgroup analyses of surgical outcome were performed for small (<12Δ) versus large (>20Δ) preoperative hypertropia in the group that underwent inferior oblique weakening, and for inferior oblique disinsertion-myectomy versus inferior oblique recession. Results Mean forced primary position (PP) hypertropia decreased from 14.3Δ (range 3–37Δ) to 4.5Δ (range 0–30Δ) in Group 1, from 13Δ (range 1–30Δ) to 2Δ (range -20–20Δ) in Group 2, and from 25.7Δ (range 6–40Δ) to 1.3Δ (range -12–18Δ) in Group 3. Group 1 had the lowest re-operation rate (7.6%), followed by Group 2 (16%) and Group 3 (25.9%). Final surgical success rates were similar in three groups. Inferior oblique weakening was more predictable for small primary position hypertropia, but still yielded 85% success rate in large deviations. Inferior oblique disinsertion-myectomy resulted in more favorable results than inferior oblique recession (P < 0.05). Conclusion When a predetermined surgical strategy is applied to individual patients with unilateral superior oblique palsy, excellent functional improvement can be achieved in the majority of patients.

Acquired restrictive strabismus and high axial myopia: diagnosis and management

OBJECTIVE This paper documents the clinical, ultrasound, magnetic resonance imaging (MRI), and anatomic characteristics of 6 patients with esohypotropia and high axial myopia. The results of strabismus surgery performed on these patients are evaluated. STUDY DESIGN Retrospective cohort study. PARTICIPANTS Six patients with esohypotropia and high axial myopia were selected from the practice of the second author (Michael Flanders). METHODS We extracted the history and data from the preoperative and postoperative ophthalmic and orthoptic examinations, recorded the surgical procedures, and tabulated the postoperative results. A- and B-scans, orbital MRI images, and photo documentation were obtained for all patients. Supramaximal recession and resection on the horizontal rectus muscles, using adjustable sutures, was performed in all patients. A surgical outcome was deemed successful if, in primary position, postoperative horizontal ocular alignment measured 15 prism diopters (PD) or less and (or) if diplopia was eliminated. RESULTS Echographic and MRI findings demonstrated an enlarged globe in all cases. Globe flattening on the orbital walls was found in 5 cases. Lateral rectus depression was visualized on MRI images in 4 cases. Surgical success was obtained in all patients. The average preoperative primary position esotropia measured 60 PD (25 to 90 PD) and the esodeviation after surgery was 7.0 PD (0 to 15 PD). Ductions were also improved. CONCLUSIONS Different surgical approaches to realignment of eyes with high myopia and esohypotropia have been attempted. In this study, supramaximal amounts of recession and resection on the rectus muscles provided satisfactory results.

Clinical profiles and surgical outcomes of adult esotropia

OBJECTIVE The aim of this study was to describe the clinical features and surgical outcomes of teenage and adult patients with esotropia undergoing strabismus surgery with adjustable sutures. METHODS Seventy-three patients were included in this retrospective, cohort study. Patients were stratified into group 1 (35 with childhood-onset esotropia [CET]) and group 2 (38 with adult-onset esophoria-tropia [EPT]). Preoperative immediate, 2-week, and 4-6-month postoperative measurements of ocular alignment, as well as fusional testing, were performed. Postoperative success was defined as distant (6 m) and near (33 cm) alignment within 12 prism diopters (PDs) of orthotropia in the primary position at 2 weeks and at 4-6 months with a single surgery. RESULTS Patients with CET more frequently had hyperopia and amblyopia and were more likely to present for surgery because of psychosocial strabismus-related problems. Patients with EPT predominantly had myopia and were more likely to experience diplopia and asthenopia. In group 1, the mean preoperative distance deviation improved from 30 PDs to 4 PDs at 2 weeks and to 4 PDs at 4-6 months (p < 0.001). In group 2, mean preoperative distance alignment improved from 22 to 3 PDs at 2 weeks and to 3 PDs at 4-6 months (p < 0.001). The mean objective, single-surgery success rate at 2 weeks was 88% and 97% in groups 1 and 2, respectively. At 4-6 months, postoperative success was 71% in group 1 and 80% in group 2. The majority of patients reported subjective improvement. CONCLUSIONS There are distinct preoperative differences between CET and EPT patients. Adjustable, strabismus surgery in this cohort is safe and effective in achieving subjective and objective success.

Restrictive Strabismus: Diagnosis and Management

Introduction Restrictive strabismus is a type of ocular misalignment with limitation of motility caused by intrinsic or extrinsic mechanical forces. The clinical spectrum of either purely or partially restrictive strabismus is very broad. Most cases are of congenital, traumatic, endocrine, post-paralytic or myopathic origin. The surgical treatment strategies are designed to correct abnormal head posture, to eliminate diplopia in primary and functional positions of gaze and to enhance aesthetic and psychosocial aspects of a patients life. Purpose The objective of this paper is to present a clinical approach to the diagnosis and evaluation of patients with restrictive strabismus and to propose a logical surgical approach to the correction of this type of ocular misalignment. Patients and Methods As representative of the broad spectrum of restrictive strabismus problems, twelve cases are presented and the preoperative and postoperative clinical finding are illustrated with photographs. Conclusion The clinical spectrum of either purely or partially restrictive strabismus is very broad. The clinical evaluation of patients with this problem must include a careful and detailed history, which is crucial to establishing the diagnosis and must also explore the patients concerns. Analysis of fixation, head posture, and ocular alignment require both traditional and special examination techniques. Patient and surgeon expectations must be synchronized preoperatively. A variety of surgical strategies can be applied to improve head posture, eliminate diplopia, and improve cosmesis.

Data for: Retrobulbar Anaesthesia for Adjustable Strabismus Surgery in Adults: A Prospective Observational Study

OBJECTIVE To characterize the ocular response to retrobulbar anaesthesia and to evaluate the efficacy of retrobulbar anaesthesia for adjustable strabismus surgery in adults. DESIGN Prospective observational study. PARTICIPANTS Adult patients undergoing adjustable strabismus surgery under retrobulbar anaesthesia. METHODS Surgical success was defined by ocular alignment within 10 prism diopters (PD) of orthotropia for horizontal rectus surgery and within 5 PD for vertical rectus surgery. After retrobulbar injection of Xylocaine with epinephrine, the onset time and the degree of visual impairment, ocular akinesia, and analgesia were evaluated. Postoperative parameters included the restoration of vision, onset of pain, resolution of ptosis, normalization of pupil, resolution of extraocular motility deficits, and the timing of postoperative adjustment. Perioperative complications were also documented. RESULTS A total of 33 patients were initially included in this study. Two patients experienced complications (perioperative retrobulbar hemorrhage, postoperative suprachoroidal hemorrhage) and were excluded from data analysis. Of the remaining 31 patients (mean age, 50.2 ± 14.8 years), surgical outcome was satisfactory in 30/31 (96.8%) patients at the first postoperative visit and in 15/19 (78.9%) cases at last follow-up (mean, 6.1 ± 1.6 months). Excellent intraoperative ocular akinesia and analgesia was achieved with retrobulbar anaesthesia. After retrobulbar injection, visual impairment was the first to resolve to preoperative levels within (mean ± SD) 3.7 ± 1.9 hours postinjection, followed by onset of pain at 4.1 ± 1.0 hours, resolution of ptosis at 4.3 ± 1.9 hours, and normalization of pupil reactivity at 6.1 ± 1.0 hours. The resolution of anaesthesia upon extraocular motility occurred within 5.7 ± 1.0 hours postinjection (range, 4.5-8.0 hours), allowing for subsequent same-day postoperative adjustment. CONCLUSIONS Retrobulbar anaesthesia in the context of adult, adjustable strabismus surgery is a relatively safe and effective technique. It provides excellent intraoperative analgesia and akinesia. Retrobulbar anaesthesia enables for same-day suture adjustments to be reliably performed.