Orbital Myositis: �A Case Report

Author :Dr. Harshdeep Singh Gabba, Co-Author :Dr. Varsha Kulkarni, Professor Bharati Vidyapeeth University, Medical College , Pune.

1. ORBITAL MYOSITIS: A CASE REPORT Author :Dr. Harshdeep Singh Gabba Co-Author : Dr . Varsha Kulkarni Professor Bharati Vidyapeeth University Medical College , Pune

2. Introduction Orbital M yositis : An inflammation of the extra ocular muscles with sudden onset C haracterized by- Orbital inflammation Periocular pain Swelling Redness of the eyelids Proptosis Ptosis Ocular motility restrictions Incidence-7-8% female predominance(2 :1 )

3. Case Presentation A 12 year old female presented with : B ulging of LE since 5 days Pain over LE more during ocular movement Diplopia Swelling over LE lower lid

4. Ophthalmic Examination BCVA : RE:-6/6 LE:- 6/18 6/9 with +0.75Ds Head posture: Face turn towards right. Extra Ocular Movements: LE- restriction in abduction.

5. Examination continue LE 4 mm proptosis with fullness of Left. Periorbital space . Non tender, No bruit or crepitus , Non reducible.

6. Investigation &Treatment MRI- Thickened edematous muscle belly of Medial Rectus Tab Prednisolone 30mg OD for one month on tapering dose

7. 3 Month Follow Up LE proptosis resolved,ocular motility were full and free , conjunctival congestion resolved completely, no pain on ocular movement & no diplopia . Repeated MRI after 3 months-WNL.

8. DISCUSSION I diopathic orbital myositis is classified as a subtype of nonspecific orbital inflammation 1 It commonly occurs between 7-42 years. Muscles commonly involved are medial rectus (43%), superior rectus (19%), lateral rectus (17%), and rarely oblique ’ s (5-10%). DIFFERENTIAL DIAGNOSIS: Thyroid eye disease Rhabdomyosarcoma Orbital cellulitis Orbital psuedotumor 2,4 . MRI is helpful in diagnosis.

9. Associations with bacterial/ viral infection, cysticercosis , sarcoidosis , crohn’s disease & giant cell arteritis has been reported. In our case patient was 12 years old so diagnosis of rhabdomyosarcoma was also considered. MRI showed thickening of medial rectus along with involvement of the tendon ruling out thyroid eye disease & rhabdomyosarcoma . 3 Patient responded to systemic steroids with complete regression

10. TAKE HOME MESSAGE Orbital M yositis is an important entity which should be differentiated from other ocular myopathies like rhabdomyosarcoma , orbital psuedotumors and thyroid orbitopathy . MRI is the most useful investigation for diagnosis . Steroid is the mainstay treatment for Orbital Myositis .

11. REFERENCES Espinoza GM. Orbital Inflammatory Pseudotumors : Etiology, Differential, Diagnosis, and Management. Curr Rheumatol Rep 2010;12:443-447 Benedikt GH Schoser . Ocular myositis ; diagnostic assesment , diffrential diagnoses and therapy of rare muscle disease-five new cases and review. Clincal Opthphalmolgy . 2007 Mar;1(1); 37-42 Ding ZX, Lip G, Chong V. Idiopathic orbital pseudotumor . Clinical Radiology 2011;66:886-892 Cockerham KP, Chan SS. Thyroid Eye Disease. Neurol Clin 2010;28:729-755