Two Cases of Extraocular Muscle Enlargement Caused by Metastatic Cancer

PURPOSE: To report two cases of extraocular muscle enlargement due to malignant cancer metastasis. CASE SUMMARY: A 56-year-old woman presented with horizontal diplopia first noted 1 month earlier. She had a history of small cell lung cancer with brain and bone metastases. She had a -3 abduction deficit in the right eye and esotropia. The forced duction test showed no limitation in horizontal movement. Antibody tests for thyroid disease showed normal results. Brain magnetic resonance image showed multiple nodular enlargements of the right lateral and medial rectus muscles, al so multiple metastatic nodules in the brain. A 38-year-old woman presented with horizontal diplopia first noted 3 months previously. She had undergone breast cancer surgery 6 months earlier. The patient had a -4 abduction deficit in the left eye and esotropia. The forced duction test showed no limitation in horizontal movement. Antibody tests for thyroid disease showed normal results. Orbital magnetic resonance imaging showed nodular enlargement of left lateral rectus muscle including a tendon. CONCLUSIONS: Extraocular muscle metastasis is a possible cause of extraocular enlargement and paralytic strabismus. In a patient with malignant cancer, the physician should consider the possibility of extraocular muscle metastasis and perform imaging for early diagnosis and treatment.

Comparison of Patient Characteristics in Thyroid-Associated Ophthalmopathy with and without Strabismus

PURPOSE: To determine immunochemical and clinical differences in thyroid-associated ophthalmopathy (TAO) patients with restrictive strabismus and without strabismus. METHODS: A retrospective chart review of 15 TAO patients with strabismus (25 eyes) and 24 TAO patients without strabismus (39 eyes) who presented to the Ophthalmology Clinic between August 2011 and December 2013 was performed. Visual acuity, intraocular pressure (IOP), Hertel exophthalmometry, soft tissue score, and enlargement of extraocular muscles on computed tomography (CT) were obtained and compared in each group. Thyroid related autoantibody (thyroid-stimulating hormone receptor antibody, TRAb; thyroid peroxidase antibody, TPOAb; anti-thyroglobulin antibody, TgAb) titers and positive rates were obtained at the time of diagnosis or before treatment and analyzed. RESULTS: The gender and smoking proportion were not significantly different between the 2 groups. The mean age of TAO patients with strabismus was 52.53 years and of TAO patients without strabismus 40.33 years (p = 0.004). The differences in visual acuity and IOP between the 2 groups were not significant. Hertel exophthalmometry showed less proptotis in the TAO with strabismus group than the TAO without strabismus group (16.84 mm versus 18.67 mm). The soft tissue score was not significantly different. The extraocular muscle enlargement rate of TAO with strabismus was significantly higher than in TAO without strabismus group. In the TAO with strabismus group, TRAb level was higher than in the TAO without strabismus group (p = 0.021). CONCLUSIONS: The TAO with strabismus group was older and had higher positive rate, level of TRAb, and extraocular muscle enlargement rate on CT than the TAO without strabismus group. Furthermore, proptosis was less definite in the TAO with strabismus group.

A Case of Intramuscular Hemangioma Presenting with Large-angle Hypertropia

PURPOSE: To report the case of a patient with large-angle hypertropia of an intramuscular hemangioma of the right superior rectus muscle (SR). METHODS: A 63-year-old man with progressive vertical deviation of the right eye for the past 6 months visited our strabismus department; his condition was not painful. An examination indicated that he had 60PD of right hypertropia at distance and near in primary gaze. Additionally, a significant limitation of his downgaze was noted. The right eye appeared mildly proptotic, and the upper and lower eyelids were slightly edematous. Corrected vision was 20/20 in both eyes. RESULTS: Orbital magnetic resonance imaging (MRI) studies revealed fusiform enlargement of the right superior rectus muscle, with prominent but irregular enhancement following gadolinium administration. Incisional biopsy revealed an intramuscular hemangioma in the superior rectus muscle with cavernous-type vessels. CONCLUSIONS: This case demonstrates that intramuscular hemangioma should be considered in the differential diagnosis of isolated extraocular muscle enlargement and unusual strabismus.