New-Onset Right Hypertropia: A Sequela of Inflammatory Orbital Pseudotumor

I. Case Hx: A 45 year old African American male presents as a walk-in with a new vertical deviation of his right eye. He reports slow onset over the past six months, gradually worsening. He notes constant vertical diplopia. He denies eye pain. His comprehensive eye exam six months earlier was unremarkable. No vertical deviation was noted. A mild prescription was released for distance and near. Medical conditions include carpal tunnel, osteoarthritis, and poorly controlled Type 2 diabetes mellitus with a fluctuating HbA1c. He has a history of Bell’s Palsy affecting the right side of his face, but the condition has been resolved for fifteen years without recurrence. The patient is currently taking metformin and tramadol for joint pain. II. Pertinent findings: The patient was afebrile without nausea or fatigue. No recent illnesses were noted. Clinical examination indicated a vertical hypertropia OD greater than 40 prism diopters. Pupils were normal. EOMs indicated incomplete depression OD in downgaze and slight abduction limitations OD. CVFs were full to finger counting OD, OS. Hertel exophthalmometry was 30 OD, 25 OS. Color vision was normal. On slit lamp exam, 2-3+ periorbital edema OD was noted without tenderness. There was 2+ conjunctival chemosis with trace injection OD. No follicles or papillae were noted. The patient’s left eye was completely uninvolved. No anterior chamber reaction was noted OD,OS, and IOP was 23 mmHg OD, 18 mmHg OS. Upon dilated examination, all posterior health was unremarkable. No nerve edema or abnormalities were noted OD or OS. The patient was sent for an MRI with and without contrast. A multisequential multiplanar MRI of the head was obtained. The radiology report indicated proptosis OD with enlargement of the superior and lateral recti. See figure 1. The left eye was normal. A 1.5 cm retention cyst was noted in the right maxillary sinus. See figure 2. All other sinus and cerebral structures were normal. III. Differential Diagnosis: The differential diagnoses were inflammatory orbital pseudotumor (idiopathic orbital inflammatory syndrome) versus infectious orbital cellulitis. The patient has a history of normal thyroid levels, so thyroid eye disease was not a concern. The patient had a history of chronic sinusitis, a common underlying cause of orbital cellulitis. The co-managing ophthalmologist also consulted an oculoplastics ophthalmologist to consider conducting a biopsy to rule out lymphoma if conservative treatment was ineffective. The biopsy was intended to confirm if the muscle bellies were enlarged, or infiltrated with invasive cell types. IV. Diagnosis and Discussion: Inflammatory orbital pseudotumor generally presents with unilateral periorbital edema, proptosis, redness, double vision, pain, and blurred vision. It can appear as acute, recurrent, or chronic in nature.1 The inflammation is non-infectious and space-occupying, with no systemic association.2 Restricted motility is frequently noted, as EOMs are inflamed and inhibited. Involvement of the EOMs is noted on imaging as enlarged muscle bellies and associated tendons. The subcategory of inflammatory orbital pseudotumor that involves the muscles versus general orbital tissue is called orbital myositis.1 Psuedotumor is the third most prevalent inflammatory orbital condition, following thyroid eye disease and lymphoproliferative disease.3 New-Onset Right Hypertropia: A Sequela of Inflammatory Orbital Pseudotumor

Important tests to conduct for diagnosis include a history to rule out malignancy, exophthalmometry, IOP, and a dilated view of the nerve for edema from a space-occupying lesion. A fever noted in office indicates active infection, as with an orbital cellulitis. Blood work to consider includes an ESR, CBC with differential, ANA, BUN, creatinine (before imaging with contrast), and fasting blood sugar prior to beginning the patient on oral steroids. A CBC with differential indicates active infection, while an ESR or ANA will provide information regarding inflammation. If concern for granulomatous conditions is present, a chest x-ray with an ACE test is pertinent. Because this condition is non-infectious, the mainstay of treatment is oral steroids to decrease inflammation. A biopsy of orbital tissue may be conducted to rule out malignancy if the patient is not responsive to steroid treatment.1 V. Treatment, management: The patient was started on 80 mg of oral prednisone daily with 20 mg of omeprazole for prostaglandin protection, as is the standard of care1. He was monitored at one week for progress. Exophthalmometry readings indicated 2mm of improvement in proptosis OD at one week. The abduction and depression deficits began to decrease after two weeks of steroid treatment, as function to the lateral rectus and superior rectus were gradually restored. The frequency of the right hypertropia became more intermittent instead of constant by week two. Diplopia lessened. The patient was followed weekly for follow up and progress evaluation until symptoms resolved entirely. Four weeks of oral prednisone treatment was ultimately required to decrease the orbital inflammation. The length of this treatment was longer than anticipated, but improvement in the condition at weekly intervals indicated treatment was working, albeit gradually. Once the proptosis and periorbital edema had subsided, the patient was placed on a four-week prednisone taper to prevent rebound inflammation. VI. Conclusion: Inflammatory orbital conditions may pose a threat to the health of a patient, or be indicative of serious systemic health concerns. Access to imaging and co-management with ophthalmology ensures the management of the condition are seamless, and treatment is maximized for quick resolution. References: 1. The Wills Eye Manual : Office and Emergency Room Diagnosis and Treatment of Eye Disease. 6th Edition. Philadelphia :Lippincott, 2012. 2. Shenoy C, Sattur S. A woman with orbital myositis. CMAJ : Canadian Medical Association Journal. 2007;176(2):174. 3. Weber AL, Romo LV, Sabates NR. Pseudotumor of the orbit: clinical, pathologic, and radiologic evaluation. Radiol Clin North Am 1999;37:151-68.