Predictability of strabismus surgery in children with developmental disorders and/or psychomotor retardation

Periorbital injections of botulinum toxin a: a novel therapeutic option for convergence spasm in neuropsychiatric disorders

PURPOSE

Convergence spasm (CS, spasm of near reflex) is characterized by transient attacks of convergence, miosis and accommodation, often associated with functional neurological disorders. To date, no simple and efficient treatment option is available for CS. This study investigates whether periorbital botulinum toxin injections as used in essential blepharospasm are also a treatment option in these patients.

METHODS

All patients with convergence spasm having been treated with periorbital BoNTA injections in the department of neuro-ophthalmology were identified. Data were extracted from patient files concerning details and subjective effectiveness of botulinum toxin injections and relation to psychiatric or neurological disorders. Patients reporting with a history of closed-head trauma or organic neurologic pathologies possibly causing CS were excluded. A telephone assessment with a standardized questionnaire was performed to evaluate mental health issues as a trigger, as well as the long-term effect and satisfaction with periorbital injections.

RESULTS

Of 16 patients treated with periorbital botulinum toxin injections for convergence spasm, 9 patients reported depression and/or anxiety disorders ongoing or in the past. A median number of 3 injections (range 1-13) was administered with a variable effect (relief of symptoms) between no effect and effect of up to more than 12 weeks. A longitudinal follow-up revealed ongoing symptoms in five patients.

CONCLUSIONS

Periorbital botulinum toxin injections are less invasive than injections in the medial rectus muscle and can be a bridging therapeutic option in patients with CS. Mental health exploration is important due to psychiatric comorbidity.

Strabismus surgery in Angelman syndrome: More than ocular alignment

PURPOSE

To report and evaluate strabismus surgery in children with Angelman syndrome, in order to optimize and standardize surgical approach. Other purposes are to understand the possible relation between ocular findings and motor ability, and between improvement in ocular alignment and changes in motor skills in this population.

DESIGN

Observational cross-sectional study.

METHODS

Medical records of pediatric patients with Angelman syndrome, who underwent strabismus surgery, were investigated. Collected data included: genotype, gender, age at the time of surgery, refractive error, pre-operative strabismus, surgical procedure, surgical outcome, gross and fine motor development assessment pre- and post-operatively.

RESULTS

Seventeen subjects, aged 3-15 years, were investigated. Fourteen patients were exotropic, three esotropic. Most patients presented astigmatism. Considering the exaggerated response to standard amounts of surgery and the risk of consecutive strabismus on long term follow-up reported by previous studies in children with developmental delay, a reduction of the amount of strabismus surgery was applied. Post-operatively, all patients presented with a significative reduction of the baseline deviation angle, with all esotropic patients and 7 exotropic patients (59%) achieving orthotropia. The surgical outcomes were variable according to the type and the amount of baseline strabismus, but no case presented with exaggerated surgical response. At baseline, patients showed important delays in all motor abilities, and, post-operatively, presented a significant improvement in walking and fine motor tasks. Pre- and post-operative motor abilities were negatively correlated to astigmatism, anisometropia, and amount of deviation.

CONCLUSIONS

According to our data, the standard nomograms for strabismus surgery may be successfully applied in subjects with Angelman syndrome and exotropia. Our data suggest that the reduction of the deviation angle improves motor skills in strabismic pediatric patients with Angelman syndrome.

Comparison of the Efficiency of the Botulinum Toxin for the Treatment of Esotropia in Children with and without Neurological Disease and/or Prematurity

OBJECTIVE

To compare the effect of botulinum toxin injection for the management of esotropia in patients with and without neurological disease and/or prematurity.

METHODS

A single-center, retrospective, nonrandomized controlled study was performed on botulinum toxin in 87 children divided into two groups: study group of esotropia in 56 children with neurological disease and/or prematurity and, control group of 31 healthy children with infantile esotropia. All patients were followed for at least 24 months after injection. Success was defined as motor alignment with 10^Δ of orthotropia after single bilateral botulinum injection.

RESULTS

Mean age at treatment was similar in both groups (15.5 vs 14.8 months; p = .555). Mean pretreatment deviation was similar in both groups (50.8^Δ vs 50^Δ; p = .855). The success rate was better in the control group (61.2% vs 51.7%, p = .265) at 24 months after injection, but the change in the mean angle of deviation was not statistically significant between the groups at 12 and 24 months after injection (p = .264 and p = .547, respectively). Multivariate regression analysis showed that pretreatment angle of deviation and presence of retinopathy of prematurity were significant predictors at 12 months after injection (p = .0001 and p = .004, respectively), while pretreatment angle of deviation was found to be a predictor at 24 months after injection (p = .0001).

CONCLUSIONS

Decreased angle of deviation and absence of retinopathy of prematurity were associated with a better result. There was no difference in motor alignment of esotropia in children with and without neurological disease and/or prematurity. In these patients, botulinum injection may be used as an alternative to surgery.

Tendon elongation with bovine pericardium (Tutopatch®) when conventional strabismus surgery is not possible

PURPOSE

Sometimes, a conventional recess-resect surgery may not be sufficient to obtain satisfactory ocular alignment. Patients who have previously undergone surgery and/or have a large difference in visual acuity between both eyes and do not wish to undergo surgery on the sound eye provide a surgical challenge. In these cases, tendon elongation with bovine pericardium may be an option.

METHODS

We retrospectively reviewed the charts of 38 patients who underwent strabismus surgery with tendon elongation. Before surgery, 31 had exotropia (angle -21.8 ± 5.7 degrees) and 7 esotropia (angle +19.1 ± 5.4 degrees). Reasons for tendon elongation included the following: 15 patients refused surgery on their sound eye; in 15 patients, conventional recess-resect was not possible; and in 7 patients, the elongation best fitted the motility pattern. In one patient, tendon elongation was preferred over conventional recession because of a thin sclera. Follow-up was 0.5 to 4 years.

RESULTS

At last follow-up visit, in patients with previous exotropia, the angle was -3.3 ± 5.9 degrees; in patients with previous esotropia, +0.2 ± 0.5 degrees. Most had some duction limitation in the direction of the elongated muscle. All patients but one were satisfied with the result. In the patients with previous exotropia, there was a small but nonsignificant regression to recurrence of the exodeviation (on average 0.5 degree per year).

CONCLUSIONS

Tendon elongation is a valuable addition to our strabismus surgery repertoire. However, because of duction limitations after surgery, it should be reserved for those cases in which conventional surgery is not an option.

Strabismus surgery for children with developmental delay

PURPOSE OF REVIEW

To describe recent evidence regarding the surgical approach of strabismus in children with various forms of developmental delay.

RECENT FINDINGS

There remains variability in surgical outcomes with or without dose adjustment in strabismus surgery for children with developmental delay. However, this should not deter one from performing surgery - even early surgery, as fusional potential remains possible, which can especially impact the quality of vision and quality of life in developmentally delayed children.Future prospective, comparative, long-term studies with larger sample sizes for strabismus surgery in children with developmental delay are still needed.

SUMMARY

Strabismus is one of the most common ophthalmologic findings in children with developmental delay. Surgical correction of strabismus in children with developmental delay is well tolerated and effective, although it remains slightly less predictable, which can depend on the specific type of delay or underlying neurological deficit. Careful consideration of types and severity of developmental delay and attempts to measure binocular potential can help guide the timing, dosage, and type of treatment.Reoperations tend to be more frequently encountered in this population, and this higher degree of variability should be addressed in the consent process.Considering adjusting the surgical dosage in this population, taking careful preoperative measurements, and checking for fusional potential should be taken into account when managing children with developmental delay.

Results of bilateral medial rectus recession for comitant esotropia in patients with developmental delay

PURPOSE

There is paucity of literature on surgical outcomes after strabismus surgery in patients with developmental delay. There is no consensus regarding whether standard surgical tables are applicable to these children. The goal of our study was to determine results of strabismus surgery for esotropia among these children.

METHODS

Two retrospective cohorts of patients, with developmental delay (excluding Down syndrome) and without developmental delay, who underwent bimedial recession for comitant eso-deviation between January 2005 and January 2011, meeting our criteria, were selected. Amount of surgery performed in these children was compared with standard table. This comparison gave us operated angle of deviation. This operated angle of deviation was expressed as percentage of preoperative angle of deviation to get amount of surgery performed. Response to surgery was defined as percentage of change in angle of deviation after surgery to the operated angle of deviation. Amount of surgery performed, response to surgery, and results were compared between two groups.

RESULTS

This study included 25 patients with developmental delay and 53 normal children with comitant esotropia. Age, refractive error, and preoperative angle of deviation were comparable in patients with and without developmental delay. Among patients with developmental delay, on average 72.13%±16.08 of angle of deviation was operated; response to surgery gained was 134.06%±51.62. In the control group, the average amount of surgery done was 89.08%±10.83; response gained was 89.83%±22.49. Successful outcome (±10 PD of orthophoria) was noted in 60% patients with developmental delay compared to 73.58% in control group. On average 70.67%±17.95 angle of deviation was operated in patients with developmental delay with successful outcome.

CONCLUSION

Surgical outcome in patients with developmental delay is very unpredictable. An exaggerated response to standard amounts of bimedial recession should be anticipated in these patients. Though there was no statistically significant difference, operating for 70.67%±17.95 angle of deviation is more likely to be successful.

Outcomes of strabismus surgery for esotropia in children with Down syndrome compared with matched controls

PURPOSE

Strabismus surgery dosages used in children with various neurodevelopmental disorders have been the subject of controversy. Few data have been reported regarding surgical results in individuals with Down syndrome (DS).

METHODS

A retrospective, case-control study was performed in which children with DS and previous bilateral medial rectus recession surgery were matched with similar control patients without DS. Surgical results were compared using a random coefficients model for repeated measurements for each group.

RESULTS

Sixteen patients with DS were matched with 16 control patients. Mean preoperative esotropia was 28.4 prism diopters (PD) in the DS group and 27.9 PD in the control group. No significant difference was found in surgical dosages between the two groups (P = .2402). Median surgical dosage was 4.4 mm in the DS group and 4.5 mm in the control group. Preoperative and 4-month and 24-month postoperative mean angles of esotropia were not different between groups (P = .8050). The 4-month postoperative mean angles of esotropia for the DS and control groups were 3.15 and 2.66 PD, respectively. The 24-month mean angles of esotropia for the DS and control groups were 7.09 and 6.60 PD, respectively.

CONCLUSION

Standard bilateral medial rectus recession surgical dosages need not be modified for individuals with DS.