Strabismus fixus convergens secondary to amyloidosis

Clinical and Radiological Features of Intramuscular Orbital Amyloidosis: A Case Series and Literature Review

PURPOSE

Orbital amyloidosis of the extraocular muscles (EOMs) is a rare condition, and its clinicoradiological features are not well elucidated. This study describes the characteristic clinical signs, MRI features, and potential treatment options.

METHODS

Retrospective multicenter case series and literature review of EOM amyloidosis.

RESULTS

Five cases were identified for inclusion. Common clinical findings were diplopia, ophthalmoplegia, and proptosis. Systemic amyloidosis was more likely to present with multiple muscle involvement, but no particular pattern was observed with localized disease. On MRI, amyloid deposition was characterized as a heterogeneous intramuscular mass with T2 hypointensity and post contrast enhancement. Management is dependent on the extent of disease and functional impairment; options include surgical debulking and radiation therapy.

CONCLUSION

EOM amyloidosis is uncommon. The combination of clinical and radiologic findings described in this study should lead to its clinical suspicion.

Congenital Monocular Strabismus Fixus

PURPOSE

To investigate the clinical characteristics and magnetic resonance imaging (MRI) findings of the extraocular muscle and ocular motor nerves in congenital monocular strabismus fixus.

METHODS

The retrospective observational case series of three patients with congenital monocular strabismus fixus were reviewed between January 1, 2006, and December 31, 2016. Ophthalmologic examination and thin-sectioned MRI of the ocular motor nerve and the orbit were performed on the three patients.

RESULTS

Three patients presented with unilateral non-progressive strabismus fixus with marked limitations of movement in all directions since birth. Of the three patients, one presented with esotropia, one with a large degree of exotropia and hypertropia, and one with an almost normal primary position. All three patients had normal ocular motor nerves, but adherences among the extraocular muscles, posterior Tenon's capsule, and the globe within the muscle cone on MRI. Two patients underwent strabismus surgery, but there were no postoperative improvements in the primary position and eye movements.

CONCLUSIONS

Extensive adherences among the extraocular muscles, posterior Tenon's capsule, and globe may partially explain the cause of congenital monocular strabismus fixus and why strabismus surgery was ineffective. The findings further highlight the importance of MRI in detecting and characterizing atypical forms of strabismus. [J Pediatr Ophthalmol Strabismus. 2018;55(6):363-368.].

Surgical treatment of esotropia associated with high myopia: unilateral versus bilateral surgery

PURPOSE

To compare unilateral versus bilateral surgical treatment of esotropia associated with high myopia.

METHODS

This retrospective study comprised patients who underwent surgery for esotropia with high myopia performed by the first author (Y.M.) between 2003 and 2008. Surgical results and complications were compared between patients who underwent unilateral versus bilateral surgery.

RESULTS

Nine patients were identified with average age of 44.9 years (range 8-70 years). All had bilateral high myopia (average -13.35 D, range -9.00 to -17.50 D) and esotropia of 20-75 diopters, together with hypotropia in 5 cases. Bilateral displacement of the lateral rectus inferiorly and superior rectus medially was demonstrated in each patient by computed tomography scan of the orbits and by observation during surgery. Five patients underwent bilateral surgery and 4 underwent unilateral surgery. After an average follow-up of 29 months (range 4-47 months), 4/5 patients who underwent bilateral myopexy achieved good results with postoperative esotropia of less than 8 diopters, as opposed to 2/4 patients who underwent unilateral surgery. No complications were noted.

CONCLUSIONS

Bilateral superior and lateral rectus myopexy is the preferred method of surgical correction of esotropia associated with high myopia. Additional unilateral or bilateral medial rectus recession is probably not indicated in most cases. Patients who prefer unilateral surgery can benefit from unilateral superior and lateral rectus myopexy together with medial rectus recession. This unilateral approach may yield good results particularly in young patients without markedly restricted and tight extraocular muscles.

A case of surgical repair in strabismus fixus with ptosis

Strabismus fixus is very rare and the convergent form is rarely accompanied by blepharoptosis. We successfully treated one patient with high myopia whose convergent strabismus fixus, accompanied by blepharoptosis, became severe after cataract surgery. We report the case with a discussion of its pathology. We performed levator advancement operation, bilateral lateral rectus 11 mm resection, and bilateral medial rectus 8 mm recession. The suture was removed after maintaining temporary traction suture for 6 days. Blepharoptosis was completely corrected by postoperative 2 months. Esodeviation was 15PD, which was not increased compared with immediately after surgery. Satisfactory cosmetic outcome was obtained.

Bilateral recession-resection surgery for convergent strabismus fixus associated with high myopia

The authors report two patients with more than 20 diopters of myopia, severely restricted abduction, and more than 90Delta of acquired esotropia. Marked axial elongation of the globes was present. Each underwent large bilateral medial rectus recessions and bilateral lateral rectus resections. The deviations were significantly reduced and abduction improved with combined horizontal recession-resection surgery on both eyes.

Amyloid deposition in the extraocular muscles

Orbital involvement is frequent in generalised amyloidosis. However, primary localised amyloid in the orbit is rare and requires systemic investigation. We present a case with amyloid deposits localised to one extraocular muscle in whom systemic investigation has been negative.