Spontaneous Recovery of Inferior Oblique Overaction in Three Saudi Children: A Case Report

The inferior oblique muscle overaction (IOOA) results in eye elevation on adduction, head tilt, difficulty in reading/writing, and changing ocular alignments in different gazes. Surgical correction is the management. We present two cases of bilateral and one case of unilateral IOOA that resolved spontaneously, and surgery differed. There was no IOOA six months after diagnosis. A sustained resolution IOOA following correction of hyperopia, improvement of vision, and esotropia correction possibly leading to rebalancing and maturing of extraocular muscles. Ophthalmologists should refer all IOOA cases to strabismologists, should not hurry to operate, counsel parents, and monitor a child's ocular movements.

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.

Histologic and Immunohistochemical Evaluation of Radiosurgery in Strabismus Surgery in a Rabbit Model

PURPOSE

The aim of this study was to evaluate the use of monopolar radiosurgery (MRS) assisted strabismus surgery and to compare its histologic and immunohistochemical wound healing outcomes with conventional surgery.

MATERIALS AND METHODS

Superior rectus muscle resection was performed on 30 white rabbits with three different surgical muscle cutting techniques: monopolar radiosurgery (MRS group), conventional scissors preceded by bipolar electrocautery (BEC group), and conventional scissors with no cauterization (control group). Degree of tissue injury, bleeding, inflammation, and fibrosis, as well as wound healing rate (CD68+ cell number), were evaluated.

RESULTS

In CS group, hemorrhage scores were significantly higher than those in the other groups (MRS group: Z = 5.182; p < 0.001 and BEC group: Z = 4.463; p < 0.001) and MRS group had lower scores than BEC group; however, the difference was not significant (Z = 1.423; p = 0.211). The tissue injury score in BEC group was higher when compared with MRS, and the difference was statistically significant (p = 0.028). Median inflammation scores at days 1 and 21 were lowest in MRS group, but the difference was not statistically significant among groups (day 1; p = 0.115, day 21; p = 0.095). The median fibrosis score was higher in the control group, when compared with MRS, and the difference was statistically significant (muscle-sclera; p = 0.011 and muscle-conjunctiva: p = 0.003). The macrophage score (number of CD68+ cells) was lowest in CS group; however, the difference was not significant (p = 0.657).

CONCLUSIONS

Monopolar radiosurgery is a novel method for strabismus surgery and provides equivalent hemostasis effects and wound healing properties, compared with conventional methods, and enhances surgeon comfort, as muscle incisions are made in one step with clean surgical area.

Pseudo-pheochromocytoma due to obstructive sleep apnea: a case report

SUMMARY

Obstructive sleep apnea (OSA) is a condition of intermittent nocturnal upper airway obstruction. OSA increases sympathetic drive which may result in clinical and biochemical features suggestive of pheochromocytoma. We present the case of a 65-year-old male with a 2.9-cm left adrenal incidentaloma on CT, hypertension, symptoms of headache, anxiety and diaphoresis, and persistently elevated 24-h urine norepinephrine (initially 818 nmol/day (89-470)) and normetanephrine (initially 11.2 µmol/day (0.6-2.7)). He was started on prazosin and underwent left adrenalectomy. Pathology revealed an adrenal corticoadenoma with no evidence of pheochromocytoma. Over the next 2 years, urine norepinephrine and normetanephrine remained significantly elevated with no MIBG avid disease. Years later, he was diagnosed with severe OSA and treated with continuous positive airway pressure. Urine testing done once OSA was well controlled revealed complete normalization of urine norepinephrine and normetanephrine with substantial symptom improvement. It was concluded that the patient never had a pheochromocytoma but rather an adrenal adenoma with biochemistry and symptoms suggestive of pheochromocytoma due to untreated severe OSA. Pseudo-pheochromocytoma is a rare presentation of OSA and should be considered on the differential of elevated urine catecholamines and metanephrines in the right clinical setting.

LEARNING POINTS

Obstructive sleep apnea (OSA) is a common condition among adults. OSA may rarely present as pseudo-pheochromocytoma with symptoms of pallor, palpitations, perspiration, headache, or anxiety. OSA should be considered on the differential of elevated urine catecholamines and metanephrines, especially in patients with negative metaiodobenzylguanidine (MIBG) scan results.

Extraocular Muscle Transplantation for Primary Treatment of Large-Angle Exotropia

AIM

To report the feasibility and outcomes of muscle transplantation combined with a unilateral recession-resection procedure for primary large-angle [≥60 Prism Diopters (PD)] exotropia.

METHODS

We retrospectively reviewed medical records of patients from three tertiary eye-care institutes who underwent unilateral recess-resect with muscle transplantation for primary treatment of large angle exotropia between August 2017 and July 2020. Motor and restorative success were defined as alignment ≤10PD of orthotropia and ≤12PD of manifest deviation, respectively, at the final follow-up. Patients with at least 3 months of follow-up were included.

RESULTS

Ten patients; six males and four females (median age 26 years) met the study criteria. The median follow-up was 12.89 months. The median preoperative exotropia reduced from 65PD (60 to 90PD) to 10PD (0 to 25PD) at final follow-up (p = .0019). The median correction obtained for the entire procedure (recession + resection + muscle transplantation) was 3.05 (1.8 to 4.3) PD/mm. Motor and restorative success was achieved in 60% and 70% of the patients, respectively. The median abduction limitation was -1 (0 to -1) at the final follow-up and there were no palpebral fissure changes beyond 6 weeks postoperatively.

CONCLUSIONS

Unilateral muscle transplantation combined with the recession-resection procedure could be a useful alternative for the management of large-angle exotropia.

Adjustable Sutures in the Treatment of Strabismus: A Report by the American Academy of Ophthalmology

PURPOSE

To review the scientific literature that evaluates the effectiveness of adjustable sutures in the management of strabismus for adult and pediatric patients.

METHODS

Literature searches were performed in the PubMed database through April 2021 with no date limitations and were restricted to publications in English. The searches identified 551 relevant citations, of which 55 were reviewed in full text. Of these, 17 articles met the inclusion criteria and were assigned a level of evidence rating by the panel methodologist. The search included all randomized controlled studies regardless of study size and cohort studies of 100 or more patients comparing the adjustable versus nonadjustable suture technique, with a focus on motor alignment outcomes or reoperation rates.

RESULTS

The literature search yielded no level I studies. Of the 17 articles that met the inclusion criteria, 11 were rated level II and 6 were rated level III. Among the 12 studies that focused on motor alignment outcomes, 4 small randomized clinical trials (RCTs) did not find a statistically significant difference between groups, although they were powered to detect only very large differences. Seven of 8 nonrandomized studies found a statistically significant difference in motor alignment success in favor of the adjustable suture technique, both overall and in certain subgroups of patients. Successful motor alignment was seen in both exotropia (in 3 studies that were not limited to children) and esotropia (in 1 study of adults and 2 of children). The majority of included studies that reported on reoperation rates found the rates to be lower in patients who underwent strabismus surgery with adjustable sutures, but this finding was not uniformly demonstrated.

CONCLUSIONS

Although there are no level I studies evaluating the effectiveness of adjustable sutures for strabismus surgery, the majority of nonrandomized studies that met the inclusion criteria for this assessment reported an advantage of the adjustable suture technique over the nonadjustable technique with respect to motor alignment outcomes. This finding was not uniformly demonstrated among all studies reviewed and warrants further investigation in the development and analysis of adjustable suture techniques.

Surgical repair of traumatic isolated inferior rectus muscle avulsion

PURPOSE:

To report our experience in the management of avulsion of the inferior rectus muscle.

METHODS:

We describe the approach we have used for surgical repair of isolated avulsion of the inferior rectus muscle in two patients who suffered orbital trauma.

RESULTS:

In both cases, the proximal portion of the inferior rectus muscle was located successfully by the generated muscle force duction test and sutured back into its original insertion point. Infraduction was normal and orthotropia was present in all directions of gaze during 1 year of postoperative follow-up in both cases. These favorable outcomes are attributed in part to the inferior rectus muscle pulleys system and the natural history of this type of injury, which allows the lost proximal portion to be identified by generated muscle force duction test.

CONCLUSION:

Generated muscle force duction test can be used to locate the proximal portion of a lost inferior rectus muscle and restore its function in patients with traumatic avulsion injury involving an extraocular muscle.

Combination management by C-arm fluoroscopy and extraocular muscle severance for penetrating ocular trauma with a retrobulbar foreign body

We report here the successful removal of a retrobulbar metallic foreign body in a patient with penetrating ocular trauma by a transconjunctival approach and combination management with C-arm fluoroscopy and extraocular muscle severance. A 37-year-old man sustained a penetrating injury to the right eye while using an iron hammer. Initial slitlamp examination revealed a corneoscleral laceration, iridocele, anterior chamber collapse, and a traumatic cataract. Visual acuity in the right eye was limited to the perception of hand motion. Computed tomography revealed an orbital foreign body in the retrobulbar area. The patient underwent corneoscleral suturing, severance of extraocular muscles, removal of the foreign body with guidance by C-arm fluoroscopy, pars plana lensectomy, and pars plana vitrectomy. Combination management with C-arm fluoroscopy and extraocular muscle severance may thus be a suitable approach to the removal of a retrobulbar metallic foreign body.