Alternate day exotropia

A Conservative Approach by Unilateral Maximal Single-Muscle Recession Surgery for the Treatment of Cyclic Esotropia

Purpose

Cyclic esotropia (alternate-day squint) is a poorly understood form of strabismus that mostly occurs at younger pediatric ages. It demonstrates classically a 48-hour cycle with 24 hours of manifest esotropia and 24 hours of orthotropia, which is conventionally managed by bilateral or unilateral 2-muscle surgery. We aimed to report a child with cyclic esotropia who was surgically treated by a conservative unilateral 1-muscle approach.

Methods

Case report.

Results

A 3.5-year-old girl presented to the strabismus department with an intermittent esodeviation for 2 years that became cyclic in the last 3 months. The diagnosis of primary classical cyclic esotropia was made after seeing her multiple times on different days. The girl was emmetropic bilaterally, had normal visual acuities in both eyes, and high-angle right esodeviation (45-50 ^Δ ) with normal laboratory and MRI results. Unilateral maximal single-muscle recession of the right medial rectus was performed, and the child was followed up for 9 months. The girl developed excellent alignment after the surgery both at distance and near without cyclic pattern, and near-normal stereopsis (by animals: 100 sec. of arc) with binocularity was reached. The girl did not experience under- or overcorrection nor have a recurrence postoperatively.

Conclusion

This is the first report of "one eye single-muscle" surgery for high-angle cyclic esotropia. Conservative unilateral medial rectus recession seems to be sufficient to permanently block the circadian rhythm and restore binocular fusion and stereopsis.

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.].

Surgical correction of persistent adult-onset cyclic strabismus

A 24-year-old man developed cyclic esotropia following vitreoretinal surgery for retinal detachment in his right eye. He underwent right eye medial rectus recession (6 mm) and lateral rectus resection (8.5 mm) under local anesthesia for the correction of cyclic esotropia. Following surgery, he developed a unique pattern of cyclic strabismus that involved alternation between esotropia and exotropia every 24 hours. To treat this condition, the patient underwent lateral rectus recession (8.5 mm) and medial rectus posterior fixation of medial rectus in the right eye. Following surgery, he was corrected for heterotropia on both esotropic and exotropic days.

Cyclic strabismus in adults

Cyclic strabismus is a rare condition that usually occurs in children and is characterized by alternating intervals of straight and strabismic eyes. In adults with the condition, strabismus surgery often eliminates the cycles. We report a case of adult-onset cyclic esotropia that was converted into a cyclic exotropia.

Adult-onset cyclic esotropia: a case report

PURPOSE

This case report presents the diagnosis and management of an adult patient with cyclic esotropia, a rare and poorly understood form of strabismus, that is characterized by alternating periods of manifest strabismus and orthotropia. Few cases of adult-onset cyclic strabismus have been reported. The etiology, pathogenesis, and treatment for this condition are reviewed.

CASE REPORT

A 37-year-old man with high unilateral myopia and anisometropic amblyopia in his left eye developed cyclic esotropia 2 months after a scleral buckle procedure for a retinal detachment. A 48-hour cycle that consisted of a 24-hour period of orthotropia followed by a 24-hour period of constant left esotropia was present. Magnetic resonance imaging, electromyography, electroencephalography, and ocular and orbital echography were unremarkable, as was a neurological assessment that included fatigue and edrophonium testing. The patient was successfully managed with muscle surgery.

CONCLUSIONS

The etiology and pathogenesis of adult-onset cyclic esotropia remain unknown. Cyclic esotropia should be considered in the differential diagnosis when an individual presents with a history of intermittent strabismus that is present some days and not others.

Cyclic exotropia in a child

Cyclic strabismus is an uncommon disorder in which strabismus alternates with orthotropia in alternating 24-hour periods, although cycles of other lengths have also been described. Alternate-day exotropia is a rare form of cyclic strabismus which, to date, has been reported in few patients. We describe a case of alternate-day exotropia in a child who had previously undergone surgical correction of constant esotropia.