Accommodative esotropia decompensated to cyclic esotropia in a 6-year-old boy

Cyclic Esotropia Managed With Botulinum A Toxin Injections: A Report of Four Cases and Literature Review

Cyclic strabismus is a rare entity and is unique in that patients follow variable but reliable time cycles where they alternate between orthotropia or "straight" eyes and strabismus, most commonly in the form of esotropia. Despite many theories on the underlying etiology and unique features of this diagnosis, none have been proven and its pathophysiology remains unknown. Four cases of cyclic esotropia diagnosed by pediatric ophthalmologists have been included in this report. The ages of the patients ranged from 10 months to eight years. The time duration from the onset of deviation to presentation to an ophthalmologist ranged from 1-52 weeks with three of the four patients presenting in the cyclic phase and the fourth presenting with a constant esotropia after a clear history and photographically documented cyclic esotropia for the preceding two months. All four patients were followed for periods ranging from one to four months to confirm their diagnosis or obtain multiple readings of the maximal deviation on the strabismic days before any intervention. The angle of esotropia when present ranged from 25 to 35 prism diopters and the cycle duration was 48 hours for all four cases (24 hours of esotropia followed by 24 hours of orthotropia). All patients were treated with botulinum toxin A injections to both medial recti, which resulted in an end to their cyclic deviation with excellent alignment obtained during follow-up periods ranging from 12-36 months for all cases. Cyclic esotropia is an elusive diagnosis that can be easily overlooked. When identified, classical treatment is usually extraocular muscle surgery targeting the largest angle of deviation. Many non-surgical treatments have been tried to no avail. However, in recent times, botulinum toxin A has been seen as a viable alternative.

Cyclic strabismus: what measured angle of strabismus should guide surgery?

Purpose: Here we aimed to describe seven pediatric patients with cyclic strabismus and report the outcome of their surgical treatment.Methods: Seven children with acquired esotropia manifesting in a 48-h cycle were included in the study. Four of them were boys, and three of them were girls. All cases had a large angle of deviation and associated suppression on the esotropic day and small angle of deviation with fusion on the other day. A complete ocular motility examination was performed for seven consecutive days. For all cases, we planned strabismus surgery according to the amount of deviation on the strabismic day. Postoperatively, the deviation angles were recorded at the first week, first month, and third month. Later, the patients were examined at 3-month intervals.Results: The mean age at presentation was 4.42 ± 3.69 years (1-12 years). The mean angle of esotropia at near fixation preoperatively was 36.4 ± 14.9 pd (prism dioptre) (20-60 pd) on the esotropic day. The mean angle of esotropia on the esotropic day at distance fixation was 32.1 ± 6.9 pd (20-40 pd). The mean follow-up period was 18.4 ± 5.5 months (12-25 months). The mean duration of esotropia before surgery was 11.1 ± 9.4 months (3-29 months). Following surgery, orthophoria within 10 pd was achieved and maintained in all cases.Conclusion: When treating children with cyclic strabismus, the best surgical results can be achieved when surgery is planned according to the amount of deviation on the strabismic day.

Role of Botulinum Toxin Type A in Cyclic Esotropia: A Long-Term Follow-up

PURPOSE

To describe two patients with childhood cyclic esotropia 8 and 9 years after they underwent botulinum toxin type A treatment to report its long-term outcome.

METHODS

Two patients with sudden onset cyclic esotropia aged 2 and 4 years were included. Botulinum toxin type A injections were performed on the appropriate muscles.

RESULTS

The first patient was a 2-year-old boy with left dominant alternating esotropia on a cyclic basis. His strabismus ranged from 25 to 45 prism diopters (PD) at near and distance. A botulinum toxin type A injection into the left medial rectus muscle revealed orthotropia at near and distance with a stereopsis of 60 seconds of arc (arcsec). During the 9 years of follow-up, he remained stable. The second patient was a 4-year-old girl who complained of double vision and strabismus. Her deviation was 40 PD at near and 35 PD at distance on a cyclic pattern. She became orthotropic with glasses after a bimedial botulinum toxin A injection. During the 8 years of follow-up, she remained stable with a stereo-acuity of 120 arcsec.

CONCLUSIONS

Considering the consecutive and recurrent deviations with surgical treatment in previous reports, botulinum toxin type A is an appropriate first-line option for the treatment of cyclic deviations, despite its limitations. The results suggest that botulinum toxin type A is an effective method to break the cycle in cyclic esotropia permanently. [J Pediatr Ophthalmol Strabismus. 2019;56(6):360-364.].

A Cluster of Cyclic Esotropia: White Matter Changes on MRI and Surgical Outcomes

PURPOSE

To report a series of patients with cyclic esotropia, their surgical outcomes, and incidental findings.

METHODS

The medical records of five patients with cyclic esotropia presenting over 17 months were reviewed. Age at onset, ocular and motility examinations, brain magnetic resonance imaging (MRI), acetylcholine receptor antibodies, thyroid hormone levels and antibodies, calendars documenting phases, surgical treatments, postoperative alignment, and fusion were documented.

RESULTS

Three boys and two girls presented at 3 to 4 years old in 2015-2016. Typical periodicity followed a 48-hour cycle. Duration of cycling varied from 1 to 9 weeks. Mean maximum deviation was 37 prism diopters (PD) of esotropia (range: 35 to 40 PD of esotropia). All patients had normal laboratory studies. MRIs showed an abnormal white matter signal in the frontal lobes in 2 patients and were normal in the others. Bilateral medial rectus recessions for the maximum angle were successful in 4 patients at a minimum follow-up of 13 months; the other patient required reoperation for a residual esotropia. Fusion was present in 4 patients preoperatively and all postoperatively. Stereopsis was stable or improved in all postoperatively.

CONCLUSIONS

This is the first report of frontal white matter changes occurring in the setting of cyclic esotropia. MRI with attention to frontal lobe white matter might be considered in the work-up of cyclic esotropia to determine if this is a common finding. Bilateral medial rectus recessions can restore fusion in these patients. [J Pediatr Ophthalmol Strabismus. 2019;56(3):178-182.].

Unusual Presentation of an Uncommon Disease: 24-Hour Cyclic Esotropia

Cyclic esotropia is an extremely uncommon form of strabismus. Classically, it follows a 48-hour cycle with 24 hours of orthotropia and 24 hours of manifest esotropia. We are reporting the first case of cyclic esotropia with a 24-hour cycle. A 7-year-old hyperopic female was seen with an esotropia of 6-month duration. Hyperopic glasses were prescribed by another ophthalmologist prior to our evaluation of the patient. While wearing her glasses, esotropia occurred during the morning and early afternoon. After 3.00pm, her eyes were “straight.” Many photographs were reviewed, confirming the esotropia pattern. Neurological evaluation was normal, including imaging and blood work to rule out thyroid pathology and myasthenia. After seeing the patient multiple times at different hours on different days, the diagnosis of cyclic esotropia was made. Bimedial recessions were performed with good results. The patient was still “straight” at distance and near 2 years after surgery.

Long-Term Follow-Up of Cyclic Esotropia

BACKGROUND AND PURPOSE

To describe the development and treatment of patients with cyclic esotropia.

PATIENTS AND METHODS

The clinical course of seven patients with cyclic esotropia were retrospectively reviewed and described. All patients underwent bilateral medial rectus recession based on the deviation manifested on the day they were esotropic. Additionally, one patient had previously undergone surgery for intermittent exotropia.

RESULTS

All patients developed excellent postoperative alignment. After strabismus surgery, normal eye alignment with some degree of binocularity was reached in five patients. Moreover, there was no recurrence of the cyclic deviation in any patient, and no patient experienced an overcorrection.

CONCLUSIONS

Strabismus surgery aimed to correct the horizontal esotropic angle present on the day the esotropia is manifested provides a good outcome that is stable long-term, with minimal risk of overcorrection. Possible explanations for the origin of cyclic esotropia are discussed.