Kelly MacKenzie

Factors associated with quality of life and mood in adults with strabismus

Background/Aims To explore the factors associated with the mood and quality of life (QoL) of patients with strabismus due to undergo realignment surgery. Methods A cross-sectional study was undertaken with adult patients. Along with demographic, clinical and psychosocial process variables, the Hospital Anxiety and Depression Scale and AS-20 QoL measures were administered. Regression models were used to identify the factors associated with QoL and mood. Results Of the 220 participants, 11% were experiencing clinical levels of depression, and 24% clinical anxiety. This is in line with other forms of facial disfigurement but higher than other chronic diseases. Although mood and QoL were associated with age and diplopia, it was beliefs and cognitions which were more consistently associated with well-being. This included feelings of social anxiety and avoidance, a belief that strabismus has negative consequences, poor understanding of strabismus, social support, fear of negative evaluation and the perceived visibility of their condition. Conclusions Psychosocial rather than clinical characteristics were identified as determinants of well-being in this population. It is important for clinicians planning surgery to be aware of these factors which could influence outcomes. Longitudinal studies need to be conducted to explore the direction of causality before interventions to improve well-being are developed and evaluated.

The impact of strabismus on quality of life in adults with and without diplopia: a systematic review

Strabismus affects approximately 4% of the adult population and can cause substantial physical disturbance and changes to appearance. This article aims to examine the impact of strabismus in adults both with and without diplopia, focusing primarily on quality of life (QoL). We highlight the value of measuring QoL, assess the ways in which it can be measured, and the impact the disease, diplopia, and surgery have on the patient. QoL differs for strabismus patients based on their diplopia status. Patients with diplopia tend to have more concerns relating to functional QoL, whereas patients without diplopia have primarily psychosocial concerns. Two diplopia-specific questionnaires have been designed to assess QoL and the perceived severity of symptoms. Further research is needed to identify the variables which influence QoL so that appropriate support can be given to all patients with strabismus to improve their QoL.

The effect on quality of life of long-term botulinum toxin A injections to maintain ocular alignment in adult patients with strabismus

Background There is considerable evidence to show that strabismus patients report their quality of life (QoL) as lower than normal controls. While the majority of patients with strabismus are treated with surgery there are a number of cases where surgery is not possible and good long-term ocular alignment can be maintained with repeated injections of botulinum toxin. Methods 65 patients who had undergone over 25 injections of botulinum toxin A for long-term control of their deviation were identified and asked to fill in and return the Adult Strabismus questionnaire (AS-20) to assess their QoL. Results 46 questionnaires were available for analysis. The mean AS-20 score in our patients compared favourably with that reported for normal controls and was much higher than that reported for patients with strabismus. Conclusion Long-term injections with botulinum toxin A is a good treatment for maintaining ocular alignment if squint surgery is not indicated and those patients receiving treatment score near the level of normal controls in QoL terms.

Does strabismus surgery improve quality and mood, and what factors influence this?

AimsTo establish the impact of adult strabismus surgery on clinical and psychosocial well-being and determine who experiences the greatest benefit from surgery and how one could intervene to improve quality of life post-surgery.MethodsA longitudinal study, with measurements taken pre-surgery and at 3 and 6 months post-surgery. All participants completed the AS-20 a disease specific quality of life scale, along with measures of mood, strabismus and appearance-related beliefs and cognitions and perceived social support. Participants also underwent a full orthoptic assessment at their preoperative visit and again 3 months postoperatively. Clinical outcomes of surgery were classified as success, partial success or failure, using the largest angle of deviation, diplopia and requirement for further therapy.Results210 participants took part in the study. Strabismus surgery led to statistically significant improvements in psychosocial and functional quality of life. Those whose surgery was deemed a partial success did however experience a deterioration in quality of life. A combination of clinical variables, high expectations, and negative beliefs about the illness and appearance pre-surgery were significant predictors of change in quality of life from pre- to post-surgery.ConclusionsStrabismus surgery leads to significant improvements in quality of life up to 6 months postoperatively. There are however a group of patients who do not experience these benefits. A series of clinical and psychosocial factors have now been identified, which will enable clinicians to identify patients who may be vulnerable to poorer outcomes post-surgery and allow for the development of interventions to improve quality of life after surgery.

What do patients with strabismus expect post surgery? The development and validation of a questionnaire

Aims To develop and validate a short questionnaire to assess patients’ expectations about outcomes post strabismus surgery. Methods Questionnaire items were extracted from previous literature and reviewed by a multidisciplinary team. A cross-sectional study was then undertaken with 220 adult patients due to undergo strabismus surgery. Participants completed the 17-item questionnaire. Scale structure was explored using principal component analysis (PCA), and the subscales analysed in relation to demographic and clinical characteristics and psychosocial well-being in order to establish validity. Results PCA revealed a 3-factor solution for the Expectations of Strabismus Surgery Questionnaire (ESSQ): (a) intimacy and appearance-related issues, (b) visual functioning, (c) social relationships. This 3-factor solution explained 59.30% of the overall variance in the ESSQ. Internal consistency, content and nomological and concurrent validity were considered acceptable. Conclusions Patients with strabismus have high expectations about their postsurgical outcomes. This questionnaire provides a useful tool to assess the expectations patients have about their surgery, whether these expectations change over time and how they impact on postsurgical outcomes.

Traumatic Transection of the Lateral Rectus Muscle with Chorioretinitis Sclopetaria

Abstract A man, aged 67 years, sustained monocular trauma to the left eye while gardening, presenting with light perception, complete absence of abduction, and chorioretinitis sclopetaria. At surgery, the lateral rectus was found to be transected at the equator of the globe, with an area of locally abraded sclera. A few posterior muscle fibers were identified and sutured to the residual anterior fibers. With a partial improvement of the esodeviation, after a further 6 months he proceeded to lateral transposition of the superior and inferior recti to healthy sclera 4 mm from the limbus, with adjunctive medial rectus botulinum toxin. Six months later, the angle of primary deviation remained stable at 4 prism diopters base out with improved abduction. Vision in the eye remained reduced at 20/200 (with eccentric fixation) due to macular changes secondary to the sclopetaria. In conclusion, this case describes a rare example of complete traumatic transection of the lateral rectus with chorioretinitis sclopetaria, due to orbital injury. With appropriate surgery, the angle of deviation can be considerably improved despite complete muscle transection and scleral injury.

Visual functioning in adults with Idiopathic Infantile Nystagmus Syndrome (IINS)

ABSTRACT Purpose: IINS is associated with mild/moderate visual impairment, strabismus and compensatory head postures (CHP), which can negatively impact quality of life. Standard visual acuity assessments tend to underestimate the effect of IINS on visual functioning. Published evidence on the effect of INS on quality of life is slowly emerging. Our study examines visual functioning of adults with IINS using the National Eye Institute Visual Function Questionairre-25 (VFQ-25). Methods: 38 participants were recruited to participate in the study. All participants underwent detailed clinical examination, as well as appropriate investigations and were asked to complete the self administered VFQ-25. Results: 35/38 participants completed the questionnaire. The mean age of the population was 35.1 years (range 17-64). Mean overall VFQ-25 score at baseline was 65 (SD 13, range 34-91). Participants specifically demonstrated lowest scores for the impact of IINS on mental health, role limitations and dependency. 26/35 of participants were not driving, either due to sub-normal vision, lack of confidence or difficulties with contrast sensitivity. Conclusions: IINS can have a greater than expected impact on an individual’s quality of life, without necessarily causing markedly reduced visual acuity. Our study showed lowest scores in the domains of mental health and wellbeing. Patients also reported reduced visual functioning in driving, which can impact adversely on employability and independence. Visual functioning questionnaires such as the VFQ-25 may provide more functional information on the impact of nystagmus on an individual’s quality of life than objective measures such as high contrast Snellen and/or LogMAR visual acuity.

Long-term Surgical Outcomes for Vertical Deviations in Thyroid Eye Disease

ABSTRACT Introduction: Vertical deviations in thyroid eye disease (TED) can present a surgical challenge due to the difficulty and unpredictability of surgery and the high risk of postoperative drift towards overcorrection. This study reports the postoperative outcomes of patients who underwent adjustable vertical strabismus surgery with Vicryl sutures for thyroid eye disease. Methods: We reviewed the records of patients seen for vertical TED strabismus surgery from January 2005 through December 2009. Clinical details were recorded preoperatively, post-adjustment, and at 3 weeks, 3 months, and 1 year postoperatively. Results: The study included 42 patients. Mean age was 62.4 years and 70% were female. All patients were diplopic preoperatively. The mean near vertical deviation was 21.1 prism diopters (PD) preoperatively, 4.0 PD at 3 weeks postoperatively, 5.0 PD at 3 months, and 4.4 PD at 1 year (all mean results representing undercorrection). 71.4% were free of diplopia postoperatively. Seven patients required further surgery, 2 patients needed further botulinum toxin A. Eight patients experienced an overcorrection; five at 3 weeks, seven at 3 months, and eight at 1 year. There was a significant difference in the mean near angle at tie-off post-adjustment in the patients that overcorrected compared to those that did not reverse (3.1 PD vs 7.1 PD; P=0.005). Discussion: Adjustable surgery for vertical strabismus in thyroid eye disease may result in late overcorrection and the need for further intervention. We propose that aiming for an immediate post-adjustment angle of 8 PD undercorrection for near would allow for postoperative drift and reduce the chances of a late overcorrection. This would require careful preoperative counseling of the patient in order to explain that immediate undercorrection and persistent diplopia were necessary in order to generate a better long-term result.

Magnetic Oculomotor Prosthetics for Acquired Nystagmus

Purpose Acquired nystagmus, a highly symptomatic consequence of damage to the substrates of oculomotor control, often is resistant to pharmacotherapy. Although heterogeneous in its neural cause, its expression is unified at the effector—the eye muscles themselves—where physical damping of the oscillation offers an alternative approach. Because direct surgical fixation would immobilize the globe, action at a distance is required to damp the oscillation at the point of fixation, allowing unhindered gaze shifts at other times. Implementing this idea magnetically, herein we describe the successful implantation of a novel magnetic oculomotor prosthesis in a patient. Design Case report of a pilot, experimental intervention. Participant A 49-year-old man with longstanding, medication-resistant, upbeat nystagmus resulting from a paraneoplastic syndrome caused by stage 2A, grade I, nodular sclerosing Hodgkins lymphoma. Methods We designed a 2-part, titanium-encased, rare-earth magnet oculomotor prosthesis, powered to damp nystagmus without interfering with the larger forces involved in saccades. Its damping effects were confirmed when applied externally. We proceeded to implant the device in the patient, comparing visual functions and high-resolution oculography before and after implantation and monitoring the patient for more than 4 years after surgery. Main Outcome Measures We recorded Snellen visual acuity before and after intervention, as well as the amplitude, drift velocity, frequency, and intensity of the nystagmus in each eye. Results The patient reported a clinically significant improvement of 1 line of Snellen acuity (from 6/9 bilaterally to 6/6 on the left and 6/5–2 on the right), reflecting an objectively measured reduction in the amplitude, drift velocity, frequency, and intensity of the nystagmus. These improvements were maintained throughout a follow-up of 4 years and enabled him to return to paid employment. Conclusions This work opens a new field of implantable therapeutic devices—oculomotor prosthetics—designed to modify eye movements dynamically by physical means in cases where a purely neural approach is ineffective. Applied to acquired nystagmus refractory to all other interventions, it is shown successfully to damp pathologic eye oscillations while allowing normal saccadic shifts of gaze.