Ocular Realignment Research Articles

Psychosocial Improvements in Children and Their Parents Following Strabismus Surgery.

To evaluate the psychosocial effects of strabismus surgery, the authors investigated the psychiatric symptoms and quality of life of children with strabismus and their parents. Children with strabismus between 6 and 18 years old (n = 39) and their parents (n = 39) were included. Psychiatric problems and the health-related quality of life were assessed with the Child Behavior Checklist and Pediatric Quality of Life Inventory, respectively. The State-Trait Anxiety Inventory for Children and Beck Anxiety Inventory were administered to children and parents, respectively. All assessments were conducted before and 3 months after strabismus surgery. Compared with preoperative assessments, children with strabismus had significantly fewer psychiatric problems and a better quality of life after the surgery (P < .001). Following surgery, decreased symptom levels of anxiety scores were also obtained from children and their parents (P < .001). The amount of ocular realignment was directly correlated with improvement in social and attention problems among children (r = 0.354 and r = 0.324, respectively; P < .05). Successful strabismus surgery has positive effects on psychosocial functioning and quality of life in children and their families. Surgical interventions seem beneficial for the management of strabismus in improving both physical and mental health. [J Pediatr Ophthalmol Strabismus. 2022;59(4):261-268.].

Does Correction of Strabismus Improve Quality of Life in Children with Autism Spectrum Disorder: Results of a Parent Survey by Ophthalmologists

ABSTRACTPurpose: Ophthalmic problems are reported to be common in children with autism spectrum disorder (ASD), and strabismus is of particular importance. We aimed to investigate the outcomes of strabismus management in cases with ASD and identify the impact of optical or surgical correction of the strabismus on the child using a questionnaire for parents. Methods: A survey was designed to assess parents’ perceptions of pre-management and post-management quality of life in 41 children aged 5–17 years with ASD and strabismus using a questionnaire with 10 questions, including three subscales. Results: Significant improvements were noted after management in functional limitations (P < 0.01), psychosocial interactions (P < 0.01), and ocular alignment (P < 0.01) subscales. Conclusion: This is the first study of the literature that investigated the impact of ocular re-alignment on behavioral patterns and social interactions of children with ASD and strabismus.

The Impact of Congenital Strabismus Surgery on Quality of Life in Children.

Purpose:To assess quality of life (QOL) in children undergoing strabismus surgery.Methods:This prospective cohort study included 87 children (including 41 boys, 47.1%) with mean age of 8.7 ± 4.1 years at three academic eye hospitals in Tehran. A modified version of the RAND Health Insurance Study QOL questionnaire was filled based on interviews with parents before and three months after surgery. The questionnaire consisted of 36 Likert scale items ranging in score from 0 to 100, with higher scores representing better function. Relevant items were averaged together and categorized into 11 distinct QOL dimensions.Results:The majority of QOL dimensions improved after strabismus surgery including functional limitation (92.36 ± 16.78 vs. 82.15 ± 20.92, P < 0.01), anxiety (68.61 ± 18.15 vs. 60.28 ± 19.19, P < 0.01), depression (82.31 ± 16.42 vs. 72.36 ± 17.72, P < 0.01), positive well-being (73.33 ± 14.69 vs. 70.56 ± 15.96, 0.048), social relations (79.43 ± 11.52 vs. 68.69 ± 30.98, 0.002), general health perception (76.4 ± 16.48 vs. 67.36 ± 18.9, P < 0.01), resistance/susceptibility (79.72 ± 13.4 vs. 71.02 ± 14.58, P < 0.01), satisfaction with development (73.81 ± 16.07 vs. 70.07 ± 14.98, P = 0.006), and eye alignment concerns (75.44 ± 15.89 vs. 53.14 ± 26.61, P < 0.01). Only self-reported prior health (71.73 ± 15.9 vs. 72.78 ± 15.29, P = 0.33) and parent-child closeness (72.92 ± 15.82 vs. 72.5 ± 17.99, P = 0.73) did not significantly improve. The amount of ocular realignment (more vs. less than 20 prism diopters [PD]) had a direct correlation with improvement in subscales of satisfaction with development (0.019) and eye alignment concerns (0.028).Conclusion:Strabismus surgery positively impacts physical and psychosocial function in children. Children with a greater amount of correction experienced more QOL improvement after surgery.

Preoperative Factors Affecting Stereopsis after Surgical Alignment of Acquired Partially Accommodative Esotropia

Background/Aim: Despite successful ocular realignment, many strabismus patients never develop high levels of stereopsis. The purpose of this study was to determine preoperative factors that affect postoperative stereopsis in patients with acquired partially accommodative esotropia (APAET).Methods: This was a retrospective chart review of patients who underwent successful surgery for APAET. We compared preoperative factors between patients achieving postoperative stereopsis of 100 seconds of arc or better versus those with worse than 100 seconds of arc.Results: Fifty-seven patients met our inclusion criteria. Twenty-four (42%) had a final stereopsis of 100 seconds of arc or better. The mean age of onset of esodeviation for patients attaining stereopsis of 100 seconds of arc or better was 31.8 ± 12.9 months, versus 23.9 ± 10.0 months (p = 0.012) for patients with worse than 100 seconds of arc. Duration of constant misalignment was not significantly different between the two groups (30.1 ± 18.5 for patients attaining 100 seconds of arc versus 27.3 ± 18.6 months; p = 0.57). A multivariate regression analysis found older age of onset to be the only predictive factor for achieving better postoperative stereopsis (odds ratio 1.065, 95% CI: 1.014–1.118).Conclusion: Age of onset appears to be the most important factor affecting postoperative stereopsis in patients with APAET. Patients with an age of onset after 36 months tended to have better outcomes regardless of the duration of misalignment. Duration of misalignment and age at surgery did not have a significant impact on postoperative stereopsis in our patient population.

Acute onset incomitant image disparity modifies saccadic and vergence eye movements.

New-onset impairment of ocular motility will cause incomitant strabismus, i.e., a gaze-dependent ocular misalignment. This ocular misalignment will cause retinal disparity, that is, a deviation of the spatial position of an image on the retina of both eyes, which is a trigger for a vergence eye movement that results in ocular realignment. If the vergence movement fails, the eyes remain misaligned, resulting in double vision. Adaptive processes to such incomitant vergence stimuli are poorly understood. In this study, we have investigated the physiological oculomotor response of saccadic and vergence eye movements in healthy individuals after shifting gaze from a viewing position without image disparity into a field of view with increased image disparity, thus in conditions mimicking incomitance. Repetitive saccadic eye movements into a visual field with increased stimulus disparity lead to a rapid modification of the oculomotor response: (a) Saccades showed immediate disconjugacy (p < 0.001) resulting in decreased retinal image disparity at the end of a saccade. (b) Vergence kinetics improved over time (p < 0.001). This modified oculomotor response enables a more prompt restoration of ocular alignment in new-onset incomitance.

Strabismus in Cerebral Palsy: When and why to Operate

Cerebral palsy (CP) is the most common physical disability in children. Orthoptists and ophthalmologists who care for children with CP know that strabismus is a common feature. This paper reviews the literature on strabismus in patients with CP, and then provides summary data and recommendations for management of these patients. The incidence of strabismus in patients with CP, especially in patients with spastic diplegia, is much higher than in neurologically normal children. Esotropia is the most common ocular misalignment. CP patients with strabismus benefit from nonsurgical treatment and should be treated promptly. Strabismus surgery should be considered in CP patients for psychosocial reasons as well as for potential successful ocular realignment and restoration of binocular vision. The literature is lacking in a long-term natural history study, prospective strabismus surgery studies, and long-term outcome studies of strabismus management in patients with CP.

Surgical outcomes following ocular re-alignment in various types of squints

Background: Strabismus is one of the causes for visual impairment in childhood. It affects the development of binocular single vision. Therefore, early detection and timely management of strabismus is important. Aim: This study was aimed to describe types of strabismus patients presenting to a tertiary care center and the various management modalities including the surgical outcomes of ocular re-alignment Materials and Methods: Retrospective chart analysis of all patients with strabismus in any age group over a period of 5 years. Patients with cerebral palsy were excluded from this study. Surgical outcomes were graded as good if the eyes were orthophoric post-operatively, satisfactory if there was a residual squint of less than 10 degrees, and it was considered to be a poor outcome if the patients were left with more than 10 degrees of residual squint. Results: Chart analysis of 53 cases with strabismus comprising of 33 males and 20 females was done. The mean age of patients was 25 years. Thirty-two (60%) cases had exotropia, and 14 (26%) had esotropia. Three cases were of congenital superior oblique palsy, and one case was of lateral rectus palsy. Duane syndrome type I was seen in four cases. Of the 38 (72%) patients who were advised surgical correction, only 20 individuals underwent surgery. Reasons for refusal of surgery varied from fear factor to financial constraints and a disregard for cosmesis. Surgeries had been performed on both children (7) as well as adults (13). Seventy-five percent of the operated patients had exotropia. Eighteen patients underwent single-staged surgery. Bilateral recessions were the most common type of surgery noted in this study. Fifty percent of them remained orthophoric up to one year of post-operative follow up. Conclusion: Exotropia was the most common type of strabismus observed in this study. Successful ocular re-alignment was seen in majority of the patients following a single-stage procedure. Greater effort needs to be made to educate the public on need for early diagnosis and management.

Persistent diplopia following secondary intraocular lens placement in patients with sensory strabismus from uncorrected monocular aphakia

Aim:To evaluate the incidence of persistent diplopia after secondary posterior chamber intraocular lens (PCIOL) implantation in patients with prolonged uncorrected monocular aphakia with associated sensory strabismus.Methods:A retrospective institutional case series...

Long-Term Results of Bilateral Medial Rectus Recession for Congenital Esotropia

This study assessed the long-term results of orthophoria obtained with bilateral medial rectus recession for congenital esotropia. The medical records of 214 patients who underwent bilateral medial rectus muscle recession between January 1995 and January 2000 were reviewed. Patients were excluded if neurological abnormalities or developmental delays were documented and if structural eye abnormalities were present. Mean follow up was 54.2 months (range, 36 to 96 months). Rates of reoperation for residual esotropia, consecutive exotropia, oblique muscle overaction, or dissociated vertical deviation were determined. Forty-five (21%) patients underwent surgery for residual esotropia, 32 (15%) underwent surgery for consecutive exotropia or dissociated horizontal deviation, and 39 (18%) underwent surgery for oblique muscle overaction and dissociated vertical deviation. To maintain long-term alignment of congenital esotropia, additional surgical procedures may be required. The success rate of bilateral medial rectus recession for ocular realignment with one operation is approximately 50%. This method is quicker, simpler, and less traumatic than three or four muscle operations. In addition, the lateral rectus and oblique muscle are left unoperated for future surgeries if necessary.

Anterior transposition of the inferior oblique muscle as the initial treatment of a snapped inferior rectus muscle

Snapping or tearing of an extraocular muscle refers to its rupture across its width, usually at the junction between muscle and tendon several millimeters behind the insertion. Tearing occurs during strabismus or retinal reattachment surgery, or after trauma.1 If the proximal end of the muscle cannot be located, transposition procedures are necessary to achieve ocular realignment. These surgical procedures carry the risk of anterior segment ischemia, especially in the elderly.1-4 Anterior transposition of the inferior oblique muscle has been used for the treatment of inferior oblique overaction, especially in the presence of a dissociated vertical deviation, and in patients with fourth nerve palsy.5,6 We transposed the inferior oblique muscle insertion in a 73-year-old woman with a snapped inferior rectus muscle. (J AAPOS 2001;5:52-4.)

Two-muscle surgery for congenital esotropia: Rate of reoperation in patients with small versus large angles of deviation

Introduction: Standard surgical treatment of congenital esotropia (CET) in patients with preoperative angles of deviation measuring ≤50 PD is well defined. However, there is controversy over the management of larger angles of esotropia. Some surgeons prefer to operate on 3 or 4 horizontal rectus muscles, while others prefer to perform large recessions of the medial rectus muscles alone. The purpose of this study was to compare the rate of reoperation after bilateral medial rectus muscle recession of smaller angle (≤50 PD) CET with the rate of reoperation after surgery for larger angle (>50 PD) CET. Methods: Medical records of 102 patients who underwent bilateral medial rectus muscle recessions between January 1991 and December 1997 were reviewed. Patients were excluded if neurologic abnormalities or developmental delays were documented before the operation, if major structural abnormalities of the eye were present, or if less than 1-month follow-up after surgery was documented. The remaining 56 patients were assigned to either the larger angle (>50 PD) or smaller angle (≤50 PD) group, based on the magnitude of their preoperative esotropia. Rates of reoperation for residual CET, for consecutive exotropia or dissociated horizontal deviation, or for dissociated vertical deviation with or without oblique muscle dysfunction were determined for each group. Results: Forty of 56 patients (71%) were assigned to the smaller angle group and 16 of 56 patients (29%) to the larger angle group. In the larger angle group, 4 patients (25%) underwent surgery for residual esotropia. In the smaller angle group, 8 patients (19%) underwent surgery for residual esotropia, 8 (19%) underwent surgery for consecutive exotropia or dissociated horizontal deviation, and 8 (19%) underwent surgery for dissociated vertical deviation or oblique muscle dysfunction. Conclusion: The success rate for ocular realignment in patients with CET by using bilateral medial rectus muscle recession did not appear to diminish when applied to deviations greater than 50 PD as compared with smaller angle deviations. Surgery on 3 or 4 horizontal rectus muscles may be unnecessary in the treatment of patients with very large angles of CET. (J AAPOS 2000;4:267-70)

Dissociated effects of botulinum toxin chemodenervation on ocular deviation and saccade dynamics in chronic lateral rectus palsy

AIMChanges in saccade velocity/amplitude characteristics (main sequence) and attenuation of distance esotropia in response to botulinum toxin (BTX-A) chemodenervation of the antagonist medial rectus were studied in a group of...

Observations on bilateral simultaneous botulinum toxin injection in infantile esotropia.

Botulinum toxin (BoTX) is an effective pharmacological alternative to the surgical management of strabismus in adults. In a previous study, we found that concurrent bilateral medial rectus muscle BoTX injections for infantile esotropia could produce stable ocular realignment without significant risk. No other investigators have used bilateral simultaneous BoTX injection. We report the results of bilateral simultaneous medial rectus BoTX injection in 57 infantile esotropia patients followed for a minimum of 12 months. The esotropic angle in 27 infantile esotropia patients under 12 months of age was reduced from 43 +/- 12 to 1 +/- 2 prism diopters. The esotropic angle in 30 infantile esotropia patients at a mean age of 24 months was reduced from 31 +/- 12 to 2 +/- 3 delta. Other variables including late onset of hyperopic refractive errors, dissociated vertical deviations, overacting oblique muscles, and consecutive exodeviations are evaluated. We regard BoTX as reliable therapy in infantile esotropia.

Effect of botulinum toxin on extraocular muscle proprioception.

Injections of botulinum toxin type A (BoTox) in one extraocular muscle (EOM) induce long lasting paretic lengthening of the muscle permitting realignment to occur in strabismus, while eye movements appear to be unaffected after the transitory period of induced paresis. It has been hypothesized a BoTox-induced change in the spindle discharge of EOMs to explain the effect in EOM length. In decerebrate lambs and goats, first order neurons of eye muscle spindles were identified in a cellular pool located in the medial dorsolateral portion of the semilunar ganglion. The belly of the muscle to which the recorded unit belonged was infiltrated with BoTox. A decrease in afferent discharge of the spindle and in its stretch sensitivity was observed. This effect began 10-15 minutes after the injection. There was no corresponding decrease in muscle tension during the first 45 minutes. This finding suggests that the block of release of acetylcholine at motor endings is earlier and more efficacious in gamma- than in alpha-motoneurons. As a result of the proprioceptive input reduction, an unbalance between the agonist and antagonist muscles should occur favouring the ocular realignment.