HEAD & NECK CT andMR Imaging in the Diagnosis of Scleritis

SUMMARY: Scleritis is a rare, underdiagnosed vision-threatening condition that can occur isolated or in association with other orbital abnormalities. The etiology of scleritis is mainly inflammatory noninfectious, either idiopathic or in the context of systemic disease. Ultrasonography remains the criterion standard in diagnostic imaging of this condition but might prove insufficient, and studies on the diagnostic value of CT and MR imaging are lacking. We retrospectively analyzed 11 cases of scleritis in which CT and/or MR imaging were performed during the active phase of disease and assessed the diagnostic utility of these techniques. Themost important imaging findings of scleritis were scleral enhancement, scleral thickening, and focal periscleral cellulitis. MR imaging is the recommended imaging technique, though posterior scleritis also can be accurately diagnosed on CT. It is important for the radiologist to be acquainted with these findings because being able to diagnose scleritis is of clinical significance and might be vision-saving. ABBREVIATIONS: CECT contrast-enhanced CT; IOID idiopathic orbital inflammatory disease Scleritis is a rare but often treatable vision-threatening condition that can occur isolated or in association with other orbital abnormalities. The most common etiology is inflammatory (noninfectious, 90% of patients), either idiopathic in the spectrum of idiopathic orbital inflammatory disease (IOID)/pseudotumor or in the context of a systemic disease. Infectious scleritis is rare (7% of cases) and is associated with predisposing factors such as surgery or trauma. Although the diagnosis of scleritis is usually based on clinical assessment and ultrasonography, the variable clinical presentation, variable ultrasonography findings, and unfamiliarity with the diagnosis account for posterior scleritis being one of the most underdiagnosed conditions in ophthalmology. Improvements in CT and MR techniques have led to important progress in ophthalmologic imaging. However, detailed studies concerning imaging of scleritis, especially MR imaging, are few and contain only small numbers of patients. This article considers the role of CT and MR imaging in the diagnosis of scleritis, emphasizing the array of imaging findings in 11 cases. CASE SERIES We describe a series of 11 cases of scleritis in 10 different patients. All cases had CT and/or MR imaging performed during the active phase of disease. Scleritis was confirmed by an experienced ophthalmologist by using clinical and imaging criteria and by the therapeutic response in doubtful cases. CT was performed in 8 cases of unilateral scleritis and MR imaging in 6 unilateral and 1 bilateral case of scleritis. Table 1 lists the clinical and diagnostic information for the 10 patients who form the basis of this report. All patients underwent laboratory testing to determine the presence of infectious and systemic inflammatory diseases. Patient 1 A 50-year-old woman with Down syndrome presented with a 5-month history of ocular pain, proptosis, and periorbital swelling on the right orbit and low-grade fever. Contrast-enhanced CT (CECT) showed signs of preand postseptal cellulitis and scleritis of the right eye (Fig 1A). Infectious cellulitis was diagnosed and antibiotic therapy started. After a lack of improvement, an inflammatory etiology (IOID) was suspected and nonsteroidal anti-inflammatory drugs were initiated. Complete resolution of symptoms was subsequently achieved with systemic corticosteroids. Eighteen months later, the same patient re-presented with similar complaints related to the left eye. Clinically, it was again thought to be infectious orbital cellulitis. On CECT, imaging findings on the left orbit were identical to the previous Received December 20, 2015; accepted after revision June 14, 2016. From the Department of Neuroradiology (M.C.D.), Centro Hospitalar de Lisboa Central, Lisbon, Portugal; and Departments of Ophthalmology (M.J.J.) and Radiology (T.A.F.), Leiden University Medical Center, Leiden, the Netherlands. Please address correspondence to Mariana Cardoso Diogo, MD, Departamento de Neurorradiologia, Hospital de São José, Rua José António Serrano, 1150 – Lisboa, Portugal; e-mail: [email protected] http://dx.doi.org/10.3174/ajnr.A4890 AJNR Am J Neuroradiol ●:● ● 2016 www.ajnr.org 1 Published July 21, 2016 as 10.3174/ajnr.A4890 Copyright 2016 by American Society of Neuroradiology. findings on the right side (Fig 1B). Because of the presence of scleritis and a history of pseudotumor, recurrent IOID (with scleritis) was diagnosed and corticosteroids started, with total recovery. Patient 2 An 11-year-old girl presented with 3 months of severe headaches that progressed to bilateral orbital pain and blurry vision. She had a history of recurrent peripheral articular pain. Ultrasonography revealed bilateral disc edema, and optic neuropathy was suspected. Gadolinium-enhanced MR imaging showed bilateral posterior scleritis (Fig 2B). In the absence of infectious parameters, an inflammatory idiopathic etiology was assumed and systemic corTable 1: Clinical data of patients with scleritis analyzed by CT and/or MR imaging Pt Duration of Symptoms US Performed, Diagnosis Clinical Diagnosis Imaging Modality Systemic Disease Final Diagnosis 1 5 mo No Infectious cellulitis CT Down syndrome IOID with scleritis 1 2 mo No Infectious cellulitis CT Down syndrome IOID with scleritis 2 3 mo Yes, disc edema Optic neuritis MRI Not found Bilateral idiopathic scleritis 3 2 mo No Intraorbital mass CT Not found Idiopathic scleritis 4 2 mo Yes, uveal mass Choroidal melanoma CT Not found Nodular idiopathic scleritis 5 Acute No Infectious cellulitis CT, MRI DRM; Colon carcinoma Infectious orbital disease with panophthalmitis 6 6 mo No Infectious cellulitis CT, MRI Down syndrome IOID with sclerouveitis 7 1 mo Yes, scleritis Scleritis or tumor MRI Granulomatosis with polyangiitis Autoimmune orbital inflammation with scleritis 8 2 mo No Uveitis CT, MRI JIA Autoimmune sclerouveitis 9 3 wk Yes, inconclusive Optic pathway condition CT, MRI None Idiopathic scleritis 10 4 wk No Optic pathway condition MRI None Idiopathic scleritis Note:—DRM indicates dermatomyositis; JIA, juvenile idiopathic arthritis; Pt, patient; US, ultrasonography. a Duration of symptoms refers to the time elapsed between onset of symptoms of scleritis (pain, vision disturbances) and the time of imaging. b Diagnosis after ophthalmologic evaluation and ultrasound and before CT and/or MRI. FIG 1. Asynchronous IOID with scleritis. A, CECT depicts outward, eccentric thickening and enhancement of the right globe wall with focal periscleral cellulitis (black arrow), compatible with posterior scleritis. There is associated preand postseptal cellulitis (white arrow) and proptosis. B, CECT 18 months after examination (A) shows almost identical findings in the left orbit. Black and white arrows point to the scleritis and cellulitis, respectively. Notice the complete resolution of the alterations of the right orbit. Also, notice involvement of the tendon of the lateral rectus anteriorly (dashed arrow). FIG 2. Bilateral inflammatory isolated scleritis: axial MR images. A, Post-Gd-DTPA T1-weighted image with fat saturation shows bilateral enhancement of the outer aspect of the sclera (white arrows) extending to the optic nerve sheath, depicting scleritis. There is also focal periscleral cellulitis. Notice the absence of ocular anomalies on the precontrast T1WI (B). 2 Diogo ● 2016 www.ajnr.org ticosteroids started, with improvement. Follow-up MR imaging showed no anomalies. Patient 3 A 68-year-old woman presented with a 2-month history of proptosis and ocular pain on the left eye. Suspecting a retrobulbar mass, CECT was performed, depicting scleritis with periscleral cellulitis. Diagnosis of inflammatory idiopathic scleritis was made, and the patient was started on nonsteroidal anti-inflammatory drugs, with clinical improvement. Patient 4 A 41-year-old woman was referred for enucleation by an ophthalmologist with the diagnosis of uveal melanoma. She had a 2-month history of vision loss and pain in the left eye. Fundoscopy and ultrasonography findings were compatible with a mass, but because of clinical uncertainty, including the presence of pain, a CECT was performed. It showed a scleral mass displacing the choroid anteriorly, with periscleral cellulitis (Fig 3). Given the cellulitis, sparing of the choroid, and the presence of pain, a diagnosis of inflammatory idiopathic nodular scleritis was suggested. Systemic corticosteroids were started, with complete resolution of symptoms, confirming the diagnosis. Patient 5 A 66-year-old woman under immunosuppression for dermatomyositis presented with sudden onset of vision loss on the left, headache, proptosis, fever, and elevated infectious parameters. MR imaging depicted preand postseptal cellulitis, scleritis, and dacryoadenitis (Fig 4A). An orbital infection was suspected, and the patient was started on antibiotics. Despite treatment, infection progressed to panophthalmitis, and a subsequent CT showed globe rupture (Fig 4B). Cultures isolated Clostridium septicum. Patient 6 A 56-year-old woman with Down syndrome complained of progressive right eyelid swelling and proptosis. Infectious cellulitis was suspected and the patient started on antibiotics, without improvement. An inflammatory idiopathic etiology was suspected and MR imaging performed, demonstrating preand postseptal cellulitis, scleritis, and uveitis, with choroidal and retinal detachments. Therapy with corticosteroids was initiated, with resolution of all ocular complaints. Patient 7 An 80-year-old woman with granulomatosis with polyangiitis (Wegener) presented with a history of left ocular pain and 1 month of left eyelid swelling. Ultrasonography identified left posterior scleritis, but because of lack of improvement on nonsteroidal anti-inflammatory drugs, MR imaging was performed to exclude malignancy. It showed left scleritis (Fig 5), dacryoadenitis, and cellulitis. The findings were consistent with inflammatory autoimmune orbital disease, and corticosteroids were started. Resolution of symptoms was achieved after adding cyclophosphamide. Patient 8 A 10-year-old boy with a history of idiopathic juvenile arthritis presented with ocular pain and diminished visual acuity of the left eye. Fundoscopy showed optic disc edema and signs of posterior uveitis, and orbital MR imaging depicted scleritis (Fig 6). Inflammatory autoimmune sclerouveitis was diagnosed, and corticosteroids and immunosuppressive medication were started, with clinical improvement. Patient 9 A 47-year-old man presented with a 3-week history of headaches and blurred vision. Ultrasonography was inconclusive. CECT depicted posterior scleritis, confirmed by MR imaging (Fig 7). Assuming an inflammatory idiopathic etiology, nonsteroidal anti-inflammatory drugs were started, with complete resolution of symptoms. Patient 10 An 8-year-old boy, with headaches for 4 weeks, presented with diminished visual acuity on the right eye. An optic neuropathy was suspected, and MR imaging FIG 3. Nodular inflammatory scleritis mimicking uveal melanoma. CECT depicts a posterior globe wall mass (black arrow) deviating the choroid-retinal layer internally (white arrow), and hence, most probably arising from the sclera. Also notice the presence of slight periscleral cellulitis. FIG 4. Infectious orbital process with scleritis followed by panophthalmitis. Post-Gd-DTPA axial T1-weighted spectral presaturation with inversion recovery image of the orbit (A) depicts scleral enhancement (black arrow) and extensive preand postseptal cellulitis, with involvement of the optic nerve sheath (white arrow) and dacryoadenitis (asterisk). CECT performed 48 hours later (B) shows lens luxation (white arrow) and inward folding of the globe wall with volume loss (black arrow), depicting globe rupture. AJNR Am J Neuroradiol ●:● ● 2016 www.ajnr.org 3 was performed, showing scleritis and focal periscleral cellulitis. An inflammatory idiopathic etiology was suspected and the patient started on corticosteroids and methotrexate, with visual recovery. DISCUSSION Although clinically scleritis is classified according to an anterior or posterior location and subdivided into diffuse or nodular (focal) forms, there has been no defined classification applied to imaging studies. Inflammation or infection of the sclera as observed on CT or MR imaging is generally referred to as “scleritis” independent of location or etiology. Anterior scleritis is the most common form, readily diagnosed on direct observation without the need for imaging. Posterior scleritis accounts for 2%–12% of cases and is widely underdiagnosed because of its rarity, variable clinical findings, and unfamiliarity with this condition of the general ophthalmologist and radiologist. The etiology of scleritis is most often inflammatory noninfectious, occurring either as an idiopathic condition (43%) or as a manifestation of a systemic disease (48%), most often autoimmune. Rheumatoid arthritis and granulomatosis with polyangiitis are the most common underlying conditions. Idiopathic inflammatory scleritis might occur isolated or associated with extraocular anomalies and, we believe, as suggested by other authors, is part of the IOID/pseudotumor spectrum. We identified a systemic disease in 2 patients (granulomatosis with polyangiitis, juvenile idiopathic arthritis). In addition, 2 patients had Down syndrome, which to our knowledge has not been specifically associated with scleritis; both patients presented with extensive IOID. Infectious scleritis is rare, particularly in the absence of predisposing factors. In our series, 1 case was identified in an immunosuppressed patient. The most distinctive clinical feature of scleritis is orbital pain, present in around 60% of patients. Orbital pain occurred in 7 of our 11 cases. From the remaining 4 cases, 3 presented with headaches. Decreased vision has been described to occur in up to 31% of patients, 3% developing permanent visual loss. We found visual symptoms in 6 cases, 5 of which resolved completely with treatment. Fever is a feature in infectious scleritis. Treatment depends on etiology and, excluding infectious causes, involves nonsteroidal anti-inflammatory drugs, corticosteroids, and immunosuppressive drugs. Correctly diagnosing scleritis is important given the potential for complications and the frequent association with systemic disease, of which scleritis might be the presenting manifestation. Because the posterior sclera cannot be directly visualized, imaging methods are needed to make or confirm the diagnosis in clinically challenging cases. Sonography is the most widely used imaging technique, but often fails to show pathognomonic findings and is of limited value in evaluating other intraorbital structures. Scleritis is frequently part of a more extensive inflammatory process, which might involve other orbital structures. In our series, sonography was performed by a specialized ophthalmologist in 4 patients and was diagnostic in 1 patient. Sonography was not performed in the remaining patients because scleritis was not clini-