Orbital involvement in Rosai-Dorfman disease

A doença de Rosai-Dorfman (DRD) ou histiocitose sinusal com linfadenopatia maciça é uma entidade clínica idiopática, rara e benigna, caracterizada pela proliferação histiocitária com linfofagocitose. Geralmente se apresenta com linfoadenomegalia cervical, no entanto pode haver acometimento extranodal, sendo a região orbitária um dos locais de possível acometimento. Na maioria dos casos é uma doença autolimitada com melhora espontânea, entretanto pode ser necessária exérese cirúrgica da lesão ou tratamento com corticosteróides e radioterapia.Neste trabalho, relatamos o caso de um paciente masculino de 29 anos, com queixa de tumoração em pálpebra inferior direita por 6 meses e história de acometimento sinusal prévio pela doença de Rosai Dorfmann. Ao exame oftalmológico apresentava proptose de olho direito e aumento de volume de pálpebra inferior direita. O exame de tomografia computadorizada de órbitas evidenciou lesão sólida extraconal em órbita direita. Após a exérese da lesão houve melhora importante do quadro clínico. O exame histopatológico associado à imuno-histoquímica confirmou o envolvimento orbitário na DRD. Revisamos também o quadro clínico, diagnóstico diferencial e tratamento desta afecção.Rosai-Dorfman disease or sinus histiocytosis with massive lymphadenopathy is a rare idiopathic and benign clinical entity, characterized by histiocytic proliferation with linfofagocitosis. It usually presents with cervical lymphadenopathy although extranodal involvement may occur. The orbital region is one of the most common extranodal sites. It is usually a self-limiting disease with spontaneous resolution but surgical excision, corticosteroids and radiotherapy may be necessary. We describe the case of a 29-years-old male patient complaining of an orbital mass sensation for 6 months and a history of previous sinus involvement from Rosai-Dorfman disease. Ophthalmic examination showed proptosis of the right eye and swelling of right lower eyelid. Computed tomography of the orbits disclosed a solid extraconal lesion in the inferior right orbit. After surgical excision there was a significant clinical improvement. Histopathologic examination confirmed the diagnosis of Rosai-Dorfman disease. We also review the clinical picture and differential diagnosis of this condition

Predicting dysthyroid optic neuropathy using computed tomography volumetric analyses of orbital structures

OBJECTIVE: To evaluate the ability of orbital apex crowding volume measurements calculated with multidetector-computed tomography to detect dysthyroid optic neuropathy. METHODS: Ninety-three patients with Graves' orbitopathy were studied prospectively. All of the patients underwent a complete neuro-ophthalmic examination and computed tomography scanning. Volumetric measurements were calculated from axial and coronal contiguous sections using a dedicated workstation. Orbital fat and muscle volume were estimated on the basis of their attenuation values (in Hounsfield units) using measurements from the anterior orbital rim to the optic foramen. Two indexes of orbital muscle crowding were calculated: i) the volumetric crowding index, which is the ratio between soft tissue (mainly extraocular muscles) and orbital fat volume and is based on axial scans of the entire orbit; and ii) the volumetric orbital apex crowding index, which is the ratio between the extraocular muscles and orbital fat volume and is based on coronal scans of the orbital apex. Two groups of orbits (with and without dysthyroid optic neuropathy) were compared. RESULTS: One hundred and two orbits of 61 patients with Graves' orbitopathy met the inclusion criteria and were analyzed. Forty-one orbits were diagnosed with Graves' orbitopathy, and 61 orbits did not have optic neuropathy. The two groups of orbits differed significantly with regard to both of the volumetric indexes (

Probing the radio emission from air showers with polarization measurements

The emission of radio waves from air showers has been attributed to the so-called geomagnetic emission process. At frequencies around 50 MHz this process leads to coherent radiation which can be observed with rather simple setups. The direction of the electric field induced by this emission process depends only on the local magnetic field vector and on the incoming direction of the air shower. We report on measurements of the electric field vector where, in addition to this geomagnetic component, another component has been observed that cannot be described by the geomagnetic emission process. The data provide strong evidence that the other electric field component is polarized radially with respect to the shower axis, in agreement with predictions made by Askaryan who described radio emission from particle showers due to a negative charge excess in the front of the shower. Our results are compared to calculations which include the radiation mechanism induced by this charge-excess process.A. Aab...J.A. Bellido...R.W. Clay...M.J. Cooper...B.R. Dawson...T.D. Grubb...T.A. Harrison...A.E. Herve...G.C. Hill...M. Malacari...S.J. Saffi...J. Sorokin...P. Wahrlich...(The Pierre Auger Collaboration

Imaging studies for diagnosing Graves&#39 orbitopathy and dysthyroid optic neuropathy

Although the diagnosis of Graves' orbitopathy is primarily made clinically based on laboratory tests indicative of thyroid dysfunction and autoimmunity, imaging studies, such as computed tomography, magnetic resonance imaging, ultrasound and color Doppler imaging, play an important role both in the diagnosis and follow-up after clinical or surgical treatment of the disease. Imaging studies can be used to evaluate morphological abnormalities of the orbital structures during the diagnostic workup when a differential diagnosis versus other orbital diseases is needed. Imaging may also be useful to distinguish the inflammatory early stage from the inactive stage of the disease. Finally, imaging studies can be of great help in identifying patients prone to develop dysthyroid optic neuropathy and therefore enabling the timely diagnosis and treatment of the condition, avoiding permanent visual loss. In this paper, we review the imaging modalities that aid in the diagnosis and management of Graves' orbitopathy, with special emphasis on the diagnosis of optic nerve dysfunction in this condition

Evaluation of Ocular Versions in Graves’ Orbitopathy: Correlation between the Qualitative Clinical Method and the Quantitative Photographic Method

Purpose. To assess the agreement between the qualitative clinical method and the quantitative photographic method of evaluating normal and abnormal ocular versions in patients with inactive Graves’ orbitopathy (GO). Methods. Forty-two patients with inactive GO had their ocular versions evaluated clinically according to three categories: normal, moderate alterations (−1 or −2 hypofunction), and severe alterations (−3 or −4 hypofunction). The subjects were photographed in the 9 positions of gaze, and the extent (mm) of eye movement in each position was estimated using Photoshop® and ImageJ and converted into degrees with a well-established method. The agreement between the two methods (qualitative vs. quantitative) for classifying ocular versions as normal or abnormal was assessed. Results. The mean quantitative measurements of versions were significantly different for each clinical category (normal, moderate alterations, and severe alterations) in the following five positions: abduction, adduction, elevation in abduction, elevation, and elevation in adduction (p<0.001). No such pattern was observed for the three infraversion positions (depression in abduction, p=0.573; depression, p=0.468; depression in adduction, p=0.268). Conclusion. The agreement was strong between the quantitative photographic method and the qualitative clinical method of classifying ocular versions, especially in lateral and supraversions, which are typically affected in GO. Digital photography is recommended for the assessment of ocular versions due to its practicality, suitability for telemedicine applications, and ease of monitoring during follow-up. This trial is registered with NCT03278964

A Comparative Study of Clinical vs. Digital Exophthalmometry Measurement Methods

Background. A number of orbital diseases may be evaluated based on the degree of exophthalmos, but there is still no gold standard method for the measurement of this parameter. In this study we compare two exophthalmometry measurement methods (digital photography and clinical) with regard to reproducibility and the level of correlation and agreement with measurements obtained with Computerized Tomography (CT) measurements. Methods. Seventeen patients with bilateral proptosis and 15 patients with normal orbits diseases were enrolled. Patients underwent orbital CT, Hertel exophthalmometry (HE) and standardized frontal and side facial photographs by a single trained photographer. Exophthalmometry measurements with HE, the digital photographs and axial CT scans were obtained twice by the same examiner and once by another examiner. Pearson correlation coefficient (PCC) was used to assess correlations between methods. Validity between methods was assessed by mean differences, interintraclass correlation coefficients (ICC’s), and Bland–Altman plots. Results. Mean values were significantly higher in the proptosis group (34 orbits) than in the normal group (30 orbits), regardless of the method. Within each group, mean digital exophthalmometry measurements (24.32 ± 5.17 mm and 18.62 ± 3.87 mm) were significantly greater than HE measurements (20.87 ± 2.53 mm and 17.52 ± 2.67 mm) with broader range of standard deviation. Inter-/intraclass correlation coefficients were 0.95/0.93 for clinical, 0.92/0.74 for digital, and 0.91/0.95 for CT measurements. Correlation coefficients between HE and CT scan measurements in both groups of subjects (r = 0.84 and r = 0.91, p<0.05) were greater than those between digital and CT scan measurements (r = 0.61 and r = 0.75, p<0.05). On the Bland–Altman plots, HE showed better agreement to CT measurements compared to the digital photograph method in both groups studied. Conclusions. Although photographic digital exophthalmometry showed strong correlation and agreement with CT scan measurements, it still performs worse than and is not as accurate as clinical Hertel exophthalmometry. This trail is registered with NCT01999790