Differential Diagnoses of Diseases Involving the Extrinsic Ocular Musculature ­ A Pictorial Essay

Introduction There are some inflammatory, infectious, and neoplastic diseases affecting the extrinsic orbital musculature (EOM) that present with pain, decreased visual acuity, and proptosis. Imaging is fundamental to the differential diagnoses of these diseases with similar clinical presentations. The present case series report has as main objective to illustrate and discuss the main pathologies that affect the orbit. Material and Methods The present series of cases discusses the main pathologies that can affect the extraocular musculature that can be characterized by computed tomography (CT) or magnetic resonance imaging (MRI) using cases from our institution. Results and Discussion The present study compiled several cases of ophthalmopathy from our institution to illustrate and address some of these pathologies, such as orbital lymphoma, Grave disease, metastases, periorbital cellulitis, and idiopathic orbital inflammatory syndrome. The diseases are discussed according to the presentation of clinical cases with emphasis on the main imaging findings of each pathology. Conclusion Computed tomography and MRI can help in the diagnosis and follow-up of the diseases that affect the EOM. We must be conversant with the main characteristics of the pathologies presented in the present case series report, since such findings together with clinical data can confirm the diagnosis of these diseases or at least help to narrow the differential diagnoses.

Ocular motility changes after inferomedial wall and balanced medial plus lateral wall orbital decompression in Graves' orbitopathy: a randomized prospective comparative study

OBJECTIVES: To compare the surgical outcomes of inferomedial wall orbital decompression (IM-OD) and balanced medial plus lateral wall orbital decompression (ML-OD) in patients with inactive Graves' orbitopathy (GO) with regard to exophthalmos reduction and ocular motility abnormalities. METHODS: Forty-two patients with inactive GO eligible for OD were randomly assigned to either the IM-OD or ML-OD groups. Pre and postoperative evaluations included Hertel exophthalmometry, sensory, and motor extraocular motility assessment, standardized photographs in the nine gaze positions, and computed tomography (CT) of the orbits. ClinicalTrials.gov: NCT03278964. RESULTS: Exophthalmometry reduction was statistically significant in both groups (p<0.001), but was greater in the ML-OD group (p=0.010). New-onset esotropia occurred in 11.1% and 23.5% of patients who underwent IM-OD and ML-OD, respectively, with no statistically significant difference in the frequency of pre and postoperative strabismus in either group. The mean increase in preoperative esotropia was 24±6.9 and 12±8.8 prism diopters in patients who underwent IM-OD and ML-OD, respectively. In the IM-OD group, abduction and elevation worsened at the first (p<0.05) and third (p<0.05) postoperative visits but were restored at 6 months. The versions did not change postoperatively with ML-OD. The preoperative CT-measured medial rectus muscle area predicted new-onset strabismus (p=0.023). Significant postoperative medial rectus muscle enlargement occurred in both groups (p<0.001). Restriction in elevation and abduction was significantly associated with enlarged inferior (p=0.007) and medial rectus muscle areas (p=0.002). CONCLUSIONS: IM-OD is as safe as ML-OD with regard to new-onset strabismus, and represents a good alternative for patients who do not require significant exophthalmos reduction. ML-OD offers greater exophthalmos reduction and smoother postoperative recovery. Patients with preoperative enlarged medial rectus muscle on CT are at risk for new-onset esotropia, and preoperative esotropia is likely to increase after OD.

Comparison of choroidal thickness in patients with active and stable thyroid eye disease / Comparação da espessura da coroide em pacientes com doença ocular tireoidiana ativa e estável

ABSTRACT Purpose: To compare the choroidal thickness in active and stable phases of thyroid eye disease. Methods: Forty-seven eyes of 47 patients with thyroid eye disease were prospectively studied. Patients were evaluated on the basis of their clinical activity scores, with scores 33 defined as active disease. Subfoveal, temporal macular, nasal macular, temporal peripapillary, and nasal peripapillary choroidal thickness measurements were performed with Cirrus enhanced depth imaging spectral-domain optical coherence tomography, and the results in the two groups were compared. Results: Twenty-four patients were int he active group, whereas 23 patients were in the stable group. Choroidal thickness was significantly higher in the subfoveal and temporal macular regions in the active group. Although the nasal macular and peripapillary values were also higher in the active group, the difference was insignificant. Conclusions: Subfoveal choroidal thickness was significantly higher in patients with thyroid eye disease in the active phase than in those with stable phase disease.

RESUMO Objetivo: Comparar a espessura da coroide nas fases ativa e estável da doença ocular tireoidiana. Métodos: Quarenta e sete olhos, de 47 pacientes com doença ocular tireoidiana foram estudados prospectivamente. Os pacientes foram avaliados com base em seus escores de atividade clínica, com escore de 33 definidos como doença ativa. As medidas subfoveais, maculares temporais, maculares nasais, peripapilares temporais e da espessura da coroide peripapilar foram realizadas com tomografia de coerência óptica de domínio espectral Cirrus EDI, e os resultados nos dois grupos foram comparados. Resultados: Vinte e quarto pacientes estavam no grupo ativo, enquanto 23 pacientes estavam no grupo estável. A espessura da coroide foi significativamente maior nas regiões macular subfoveal e temporal no grupo ativo. Embora os valores maculares e peripapilares nasais também fossem maiores no grupo ativo, a diferença foi insignificante. Conclusões: A espessura da coroide subfoveal foi significativamente maior em pacientes com doença ocular tireoidiana na fase ativa do que naqueles com doença na fase estável.

Isolated primary amyloidosis of the inferior rectus muscle mimicking Graves’ orbitopathy / Amiloidose primária isolada do músculo reto inferior simulando orbitopatia de Graves

ABSTRACT The diagnosis of Graves’ orbitopathy is usually straightforward. However, orbital diseases that mimick some clinical signs of Graves’ orbitopathy may cause diagnostic confusion, particularly when associated to some form of thyroid dysfunction. This report describes the rare occurrence of localized inferior rectus muscle amyloidosis in a patient with autoimmune hypothyroidism, who was misdiagnosed as Graves’ orbitopathy. A 48-year-old man complained of painless progressive proptosis on the left side and intermittent vertical diplopia for 6 months. The diagnosis of Graves’ orbitopathy was entertained after magnetic resonance imaging revealing a markedly enlarged, tendon-sparing inferior rectus enlargement on the left side, and an autoimmune hypothyroidism was disclosed on systemic medical workup. After no clinical improvement with treatment, the patient was referred to an ophthalmologist and further investigation was performed. The presence of calcification in the inferior rectus muscle on computed tomography, associated with the clinical findings led to a diagnostic biopsy, which revealed amyloid deposition. This report emphasizes that a careful evaluation of atypical forms of Graves’ orbitopathy may be crucial and should include, yet with rare occurrence, amyloidosis in its differential diagnosis.

RESUMO O diagnóstico de orbitopatia de Graves usualmente é fácil de ser estabelecido. No entanto, doenças da órbita que simulam alguns sinais clínicos da orbitopatia de Graves podem levar à confusão diagnóstica, particularmente quando associada à alguma forma de disfunção tireoidiana. Relatamos a ocorrência rara de amiloidose localizada no músculo reto inferior em paciente com hipotireoidismo autoimune, que recebeu inicialmente o diagnóstico errôneo de orbitopatia de Graves. Paciente masculino, 48 anos, com queixa de proptose progressiva e indolor do lado esquerdo e diplopia vertical intermitente há 6 meses. O diagnóstico de orbitopatia de Graves foi considerado após a realização de ressonância magnética, que revelou aumento importante do músculo reto inferior esquerdo, sem acometimento do tendão, e uma propedêutica sistêmica detectou hipotireoidismo autoimune. Como não houve melhora com o tratamento clínico, o paciente foi encaminhado a um oftalmologista, que realizou nova investigação. A presença de calcificação no músculo reto inferior na tomografia computadorizada, associada aos achados clínicos, levou a uma biópsia da lesão, que demonstrou a deposição de material amiloide. Este relato enfatiza como uma avaliação minuciosa das formas atípicas de orbitopatia de Graves é essencial e deve incluir a ocorrência, embora rara, de amiloidose no diagnóstico diferencial da orbitopatia de Graves.