Overview of Orbital Ultrasonography

Orbital ultrasound also has a wide range of clinical indications. For example, following examination of a patient with ocular discomfort or pain, clinicians can use ultrasonography to help confirm a diagnosis of scleritis, orbital myositis, or dacryoadenitis. Clinicians can use ultrasonography to evaluate retrobulbar tissue, including the extraocular muscles, in a patient with exophthalmos and suspected soft tissue expansion secondary to Graves’ disease. Although imaging can help narrow the range of diagnoses to consider, images are only useful in that they reveal patterns and locations of tissue involvement which may statistically be more common in certain disease entities.

A 29-year-old woman was admitted to our hospital because of fever, myalgia, and ocular pain. She had been given norgesterone and ethinylestradiol orally. Laboratory data indicated the presence of systemic inflammation together with elevated levels of muscle enzymes. Magnetic resonance imaging revealed inflammatory lesions in skeletal and extraocular muscles. The diagnosis of eosinophilic myositis was based on histopathological examination of the deltoid muscle, which showed infiltration of eosinophils into the tissue with necrotizing muscle fibers. Prednisolone treatment resulted in marked clinical improvement. This is the first case report of eosinophilic myositis in which the extraocular muscles were affected.

A 29-year-old woman was admitted to our hospital because of fever, myalgia, and ocular pain. She had been given norgesterone and ethinylestradiol orally. Laboratory data indicated the presence of systemic inflammation together with elevated levels of muscle enzymes. Magnetic resonance imaging revealed inflammatory lesions in skeletal and extraocular muscles. The diagnosis of eosinophilic myositis was based on histopathological examination of the deltoid muscle, which showed infiltration of eosinophils into the tissue with necrotizing muscle fibers. Prednisolone treatment resulted in marked clinical improvement. This is the first case report of eosinophilic myositis in which the extraocular muscles were affected.

Adenocarcinoma metastasis causing discrete extraocular muscle enlargement

Orbital myositis implies orbital inflammation confined to one or more of the extraocular muscles. Orbital computerised tomography (CT) demonstrates irregular extraocular muscle enlargement which extends anteriorly to involve the tendon (muscle insertion). Six cases of presumed orbital myositis are reported, in each of whom the diagnosis was suspected clinically and confirmed by the orbital CT scan appearances. The mean age of the patients was 33 years (range 8-45 years). All presented with painful ophthalmoplegia and the majority manifested proptosis (five cases), conjunctival congestion (five cases) and periorbital and eyelid edema (two cases). Systemic corticosteroid therapy was used in two patients initially and also in another patient who relapsed, with rapid and dramatic responses. Extraocular muscle biopsy was performed in one case, disclosing features of non-specific muscle inflammation and no evidence of vasculitis. It is considered that orbital myositis is a discrete, identifiable subgroup within the spectrum of the nonspecific idiopathic orbital inflammatory syndromes; termed previously orbital 'pseudotumours'. Although the clinical features are frequently suggestive, they are nonspecific, and non-invasive investigations such as orbital ultra-sonography and CT scanning are required for precise anatomical tissue localisation and diagnosis. The role of ocular muscle biopsy is probably limited to atypical cases, or those unresponsive to steroid therapy, particularly to exclude neoplasia. Orbital myositis may be acute, subacute or recurrent. The acute form responds well to high doses of oral corticosteroids tapered gradually, but it may recur or become chronic. The subacute form of the disease responds less well.

Perry Rosenthal, M.D 1933–2018

Assessment of Inflammation in Idiopathic Orbital Myositis With Fat-Suppressed T2-weighted Magnetic Resonance Imaging

Background Orbital myositis (OM) is a subgroup of idiopathic orbital inflammation. It can involve single or multiple extraocular muscles and result in restriction or paresis of extraocular muscles. Method We reported two unusual cases of extraocular muscle paresis in the fibrotic stage of chronic OM and reviewed the literature related to this finding. Results The first case was of a 38-year-old woman with chronic OM with large-angle right eye exotropia and right medial rectus paresis. She received a botulinum A toxin injection into the right lateral rectus muscle as a first treatment, but it was unsuccessful in correcting her deviation. Subsequently, she underwent two strabismus surgeries, which successfully resolved her diplopia in primary gaze. The second case was of a 35-year-old woman with chronic OM and left lateral rectus palsy, which was managed with a botulinum A toxin injection. Conclusion OM can cause extraocular muscle palsy in the chronic fibrotic stage of the disease.

AimsTo present a case series of relapsing migratory idiopathic orbital inflammation.Patients and methodsCase series and review of the literature. The medical records of six patients with recurrent orbital myositis or...

Idiopathic Orbital Myositis in a 9-Year-Old Girl: A Case Report

To characterize the qualitative and quantitative features of idiopathic orbital myositis (IOM) on MRI. This was a multicenter retrospective study of patients with active IOM with MRI. Patients with incomplete clinical records, poor-quality or interval scans without active myositis, and specific orbital myositis (i.e., orbital myositis secondary to an identified condition) were excluded. An enlargement ratio was calculated by dividing the diameters of the affected extraocular muscle (EOM) by the contralateral unaffected EOM. Twenty-four patients (mean age: 44.4 ± 17.8 years-old, male: 11) between 2011 and 2022 were included. One case (4.2%) was pediatric (17 years old), and 6 cases presented with recurrence. Active IOM was characterized by fusiform EOM enlargement, high T2 signal, and contrast enhancement. Average maximal EOM diameters ranged from 4.6 to 7.7 mm (enlargement ratio: 1.4-2.2). Eighteen (75%) patients had single EOM involvement, most commonly the medial rectus. Other ipsilateral structures affected included focal orbital fat (16/24, 66.7%) and lacrimal gland (8/24, 33.3%). Contralateral changes in the EOM and/or lacrimal gland were observed in 7 patients (29.2%). Patients presenting with recurrence were likely to develop ongoing recurrent episodes ( p = 0.003). Various radiological patterns of involvement described including EOM enlargement, contrast enhancement, abnormal signal, and involvement of other orbital structures are indicative of active IOM. IOM remains a heterogeneous spectrum of acute and chronic clinico-radiological presentations. Inflammation may involve other ipsilateral or contralateral orbital structures or may be bilateral despite presenting clinically as unilateral disease. Quantitative measurements may have utility in differentiating IOM from other causes of orbital myositis.

Abstract
 Introduction : Idiopathic orbital myositis, an inflammation localized at the extraocular muscles, is rarely reported in pediatrics. Until now, the prevalence and incidence of orbital myositis remain unknown. This paper aims to report a case of idiopathic orbital myositis in a young girl with headache.
 Case Illustration : A-16-year-old presented with a droopy eyelid of the left eye (LE) and double vision since 1 week before admission. She also experienced swollen eyelid and cluster headache for 5 months with no neurological abnormalities. Ophthalmic examinations showed exotropia with limited eye movement of LE. Ptosis of LE was noted with margin reflex distance 1 (MRD-1) +2 mm, while MRD-1 +6 mm for the right eye. Other examinations were unremarkable with normal funduscopy and negative RAPD. Non-contrast orbital sinus CT-Scan revealed an enlargement of the superior rectus and lateral rectus muscle. The laboratory result showed slight leucocytosis and normal ESR. High-dose intravenous corticosteroid was administered and tapered with oral steroid. The orbital clinical findings showed improvements, better ocular movements, and diminished headache complaints.
 Discussion : As a rare case, the diagnosis of orbital myositis in adolescence can be challenging and requires detailed examination, and proper imaging to exclude other diagnosis such as ophthalmoplegic migraine, infections, malignancies, or congenital lesions (hemangioma). The first-line therapy is a systemic corticosteroid, which well responded in this patient.
 Conclusion : In this patient, intravenous corticosteroid represent an effective treatment. Close monitoring of the disease progression is required after switching to oral therapy to prevent relapse.

Background Ocular extraintestinal manifestations (O-EIM) of inflammatory bowel disease (IBD) are rare, with most being attributed to scleritis, episcleritis and uveitis. Orbital myositis, however, is an exceedingly rare manifestation that is described as acute or chronic inflammation of one or more extraocular muscles leading to symptoms related to the mass effect including orbital pain, swelling, ophthalmoplegia, proptosis, and diplopia. To date, 3 reports of varying ocular myositis preceding IBD diagnosis have been described in pediatrics. Aims This report describes a case of unilateral orbital myositis, which was the initial and only symptom of newly diagnosed adolescent with Crohn’s disease (CD). Methods A chart review was conducted and placed into the context of this rare presentation. Results 15-year-old female presented with acute 6th cranial nerve palsy with ipsilateral optic disc edema, raising concern for raised intracranial pressure. Magnetic resonance imaging (MRI) revealed a retro-orbital mass on the left lateral rectus muscle, consistent with orbital pseudo tumor and myositis, no intracranial tumor or vascular lesion. She was treated with 3-month course of prednisone. An inflammatory condition was suspected based on the unusual presentation of orbital myositis which responded well to prednisone. Alternative infectious or rheumatologic causes of orbital pseudotumor were excluded and the patient was treated with corticosteroids prior to gastroenterology (GI) consultation. She was found to have elevated C-reactive protein (CRP), hypoalbuminemia and anemia at presentation. Fecal calprotectin (649)) was subsequently found to be positive at GI consultation after corticosteroid treatment initiation. Given the patient did not exhibit any GI signs or symptoms at the time of the evaluation, further GI investigations were deferred to after completion of steroids. Fecal calprotectin was persistently elevated (1463) after resolution of ocular symptoms and completion of steroids. Magnetic resonance enterography (MRE) identified inflammation of the terminal ileum. A definitive diagnosis of CD was established following upper GI endoscopy and colonoscopy with biopsies. Conclusions Orbital myositis is a rare ocular manifestation of CD. Early recognition and treatment are critical as they may precede the development of overt gastrointestinal symptoms, potentially delaying diagnosis if not considered. Given the rarity of this presentation, further studies are needed to better understand the pathophysiological link between CD and orbital myositis. Funding Agencies None

Orbital myositis occurs in typical and atypical forms. This review summarizes and updates the current state of knowledge of all forms of inflammation affecting extraocular muscle, excluding thyroid-associated orbitopathy. A comprehensive literature review of orbital myositis was performed. Orbital myositis typically occurs in an idiopathic acute form, with painful diplopia due to inflammation in 1 or more extraocular muscles of young adult females, which usually responds to a course of oral corticosteroids. Atypical forms include idiopathic chronic or recurrent orbital myositis, and myositis related to systemic autoimmune, inflammatory, and infective conditions. The commonest associated autoimmune condition is inflammatory bowel disease. Immunoglobulin G4-related ophthalmic disease often affects extraocular muscle. Drug reactions and rarely paraneoplastic disease may also cause extraocular muscle inflammation. Orbital myositis occurs in a typical acute steroid responsive form, but atypical forms related to specific autoimmune and inflammatory conditions are increasingly recognized. Orbital myositis has many similarities to uveitis and would benefit from a systematic approach to nomenclature, diagnosis, and treatment.

30 August 2007 Dear Editor, ORBITAL MYOSITIS FOLLOWING STREPTOCOCCAL PHARYNGITIS Idiopathic orbital myositis is an inflammatory process involving the extra ocular muscles. It not only occurs most frequently in young to middle-aged adults with a 2:1 female predominance, but also occurs in children. The cause is unknown, however, it has been considered that an immunopathogenic mechanism is likely.1 There have been two previously reported cases in a 36-year-old woman2 and a 13-year-old boy where orbital myositis has followed streptococcal pharyngitis.3 We now report a third case. A 9-year-old girl presented with a 40-h history of pain on movement of the right eye and several hours of swelling and purplish discolouration of the right upper eyelid. She had diplopia on lateral gaze. An initial diagnosis of periorbital cellulitis was made and she was treated with 3 days of intravenous cefotaxime and then discharged on oral cephalosporin. She re-presented 3 days after discharge with photophobia and continuing pain on eye movement. On examination, there was slight proptosis of the right eye. The right upper eye lid was swollen and there was diplopia on extreme lateral gaze. Her visual acuity was normal. Six weeks prior to the presentation, she had had an episode of severe tonsillitis with a right-sided tonsillar abscess which had been treated in hospital with intravenous penicillin for 5 days. Investigations at the second presentation showed a white cell count of 18.6 × 109/L, 14.1 × 09/L neutrophils, ESR 47, ASOT 560 iu/mL (normal < 200), anti-DNAse B 160 (normal < 20). Creatinine phosphokinase and thyroid function tests were normal. A computerized tomography (CT) scan of the orbits showed a uniform thickening of the right medial rectus muscle which enhanced after contrast administration (Fig. 1). The paranasal sinuses were normal. Computerized tomography scan showing enlargement of R medial rectus muscle. Treatment was commenced with oral prednisolone 1 mg/kg and within 48 h of starting prednisolone she was afebrile and the eyelid oedema had resolved. The steroid dose was gradually reduced over 8 weeks. On review at 4 weeks, she had no ocular symptoms. The clinical findings are typical of orbital myositis with painful eye movement, diplopia, mild proptosis and some periorbital oedema. The CT scan showed the typical muscle enlargement in the medial rectus. Orbital myositis has been described following upper respiratory tract infections.2 There are two previous cases of orbital myositis following serology or culture proven streptococcal pharyngitis. The first was a 36-year-old woman who developed periorbital myositis 2 weeks after culture proven streptococcal pharyngitis.2 There was a rapid resolution of symptoms in 5 days following institution of oral prednisolone. The second was a 13-year-old boy who developed orbital myositis in the lateral and medial recti muscles following streptococcal pharyngitis. He was treated with non-steroidal anti-inflammatory drug therapy and the symptoms resolved approximately 7 weeks after presentation.3 There are a number of post-infective complications recorded following Group A streptococcal pharyngitis which are considered to have an immunopathogenic basis. In addition to rheumatic fever and glomerulonephritis, these include post-streptococcal reactive arthritis,4 paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections,5 uveitis, erythema nodosum, tenosynovitis of the superior oblique tendon sheath and polymyalgia. Post-streptococcal polymyalgia consists of muscle pain, fever, raised antistreptolysin O titres, neutrophilia, raised inflammatory markers and normal muscle enzymes.6 Myopathic abnormalities have been observed on electromyography.6 The fever and tenderness associated with post-streptococcal polymyalgia improves within a few days of treatment with prednisolone and somewhat more slowly following non-steroidal anti-inflammatory medication. This clinical course and response to medication is similar to that observed in the present case and the other two reported cases of orbital myositis following streptococcal pharyngitis. The occurrence of polymyalgia indicates that post-streptococcal inflammatory syndromes can involve skeletal muscle tissue. This case highlights that orbital myositis is a cause of painful eye movements and mild proptosis in children and provides further support for the possibility that an immune-mediated post-streptococcal inflammation of ocular muscle is one cause.