Consecutive cyclic exotropia after surgery for adult-onset cyclic esotropia

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.

Retroequatorial myopexy in the management of adult-onset cyclic esotropia

A 65-year-old otherwise healthy female, with bilateral normal visual acuity, presented with a unique pattern of strabismus. She complained of esotropia and diplopia occurring after every 24 h. There was no history of previous injury or ocular surgery. Other differentials were ruled out and the patient was diagnosed as adult-onset cyclic esotropia. The patient underwent right eye medial rectus retroequatorial myopexy, which tackled both diplopia and strabismus, without causing exotropia on nonsquint days.

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.].

Consecutive cyclic esotropia - A case report

Cyclic esotropia, a rare condition of obscure etiology characterized by regularly alternating periods of esotropia and orthophoria. We present a case of a 7-year-old boy who underwent surgical correction for intermittent exotropia elsewhere and developed esotropia with cyclic pattern post-operatively. Initially the cycle was of half-day orthophoria and half-day esotropia, which later became one full day of esotropia and one day of orthophoria. During re-surgery, right lateral rectus was found to have a stretched scar which was resected and then advanced and medial rectus was recessed. Post-surgery the child was orthophoric without cyclic pattern.

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.

Acquired Adult Onset Cyclic Esotropia in Patients With Myopic Strabismus Fixus and Intraocular Lens Implantation

PURPOSE/BACKGROUND

Cyclic esotropia is a rare condition that mostly occurs in children, characterized by patterns of straight and strabismic days with a regular cycle of 24 to 96 hours. In this report, 2 patients of cyclic esotropia in adults who showed a regular 48-hour cycle of mild deviation on 1 day followed by a more severe deviation on the second day are presented.

METHODS

Clinical reports, clinical features, imaging findings, and surgical outcomes are presented.

RESULTS

In patient 1, a 42-year-old male with high myopia was diagnosed with progressive esotropia for 2 years. A medial and lateral rectus (LR) recession/resection was performed 9 months before. On day 1 after this surgery, a relatively mild esotropia was present which developed into a severe esotropia on day 2. Being diagnosed as cyclic esotropia with myopic strabismus fixus, he underwent a 4 mm re-recession of the medial rectus combined with a half-Jensen procedure in his right eye. After the second surgery, the cyclic pattern was no longer present. In patient 2, a 39-year-old female with high myopia had concomitant esotropia for 20 years. At 6 months following bilateral intraocular lens implantation for her high myopia, she demonstrated a cyclic strabismus. On day 1, a 25 prism dioptres esotropia was present, which increased to a 45 prism diopters esotropia on day 2. A 4 mm recession of the medial rectus and 6 mm resection of the LR was performed in her left eye. After surgery, the cyclic pattern disappeared.

CONCLUSIONS

Cyclic esotropia can occur in adults with myopic strabismus fixus subjected to horizontal strabismus surgery and with concomitant strabismus following intraocular lens implantation for high myopia. Their cyclic strabismus consisted of a mild squint on day 1 which increased in severity on day 2. The extent of surgery required for correction was based upon the "severe esotropia" experienced on day 2 and resulted in an excellent therapeutic outcome.

Cyclic (alternate day) vertical deviation--possible forme fruste of ocular neuromyotonia

PURPOSE

Cyclic ocular deviations are relatively uncommon and are seldom seen in adults. We report 3 adult patients with cyclic hypotropia that has clinical characteristics similar to neuromyotonia, suggesting a possible common etiology.

METHODS

Three consecutive patients with 48-hour cyclic hypotropia underwent full neuro-ophthalmologic, oculoplastics, and orthoptic evaluations as well as appropriate medical and neurologic studies. Examinations were arranged on consecutive days on multiple visits to document the cyclic pattern.

RESULTS

All 3 patients had sustained contraction of a vertically acting extraocular muscle lasting 24 hours and demonstrated characteristics of ocular neuromyotonia. The contraction was absent for the next 24 hours. Two of the patients had thyroid eye disease; the third patient had unilateral ophthalmoparesis and had subsequent frameless robotic radiosurgery for a cavernous sinus schwannoma. Regular cycles lasting 6, 9, or 14 months were documented by all 3 patients. In 2 patients, treatment with carbamazepine and gabapentin effectively reduced or eliminated the cycle. The cyclic deviation in the third patient resolved spontaneously.

CONCLUSIONS

On the basis of the response of these patients to membrane-stabilizing medications and the behavior noted as the cycle broke each day, we propose that cyclic vertical strabismus and ocular neuromyotonia may be related conditions with similar underlying physiology.

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.

Acquired cyclic exotropia and hypotropia

Cyclic exotropia, a very rare condition, consists of periods of exotropia and orthotropia alternating on a regular, most commonly 48-hour, cycle. Cyclic vertical deviations, including cyclic oculomotor nerve palsy, also are extremely uncommon. Cyclic esotropia, which is more common than cyclic exotropia, has been reported to occur more frequently in children than adults. We describe an adult patient who developed cyclic exotropia and hypotropia associated with monocular loss of vision.