Les métastases orbitaires [Orbital metastasis]

PURPOSE: The purpose of this paper is to present our data and to provide some conclusions about the attitude that has to be chosen when metastasis of the orbit is suspected. PATIENTS AND METHODS: Between 1965 and 1994, 571 patients with non-traumatic orbital diseases were controlled in the department of ophthalmology of Lausanne. Thirty-four cases of metastasis of the orbit were selected, that is 24 females and 10 males, aged from 1 to 81 years. Tumors of the breast are the most frequent origin of this metastasis, followed by cutaneous melanomas and pulmonary tumors. Orbital metastasis was the first sign of a malignant process in 7 patients. The histologic diagnosis was confirmed in 15 patients. The type of treatment is presented herein and the follow-up of more than half of the cases is given. RESULTS AND CONCLUSION: Orbital metastasis can develop after a long time in patients who were previously treated for malignant tumors. In several cases, orbital metastasis was the first sign of a malignant process which starts to become general. This diagnosis has to be taken into account when a patient was treated earlier for a malignant tumor, and it is reasonable to propose a biopsy or an excision biopsy in every orbital pathology which was not confirmed by clinical or paraclinical investigations.

Nuclear magnetic resonance chemical shifts with the statistical average of orbital-dependent model potentials in Kohn-Sham density functional theory

The performance of the SAOP potential for the calculation of NMR chemical shifts was evaluated. SAOP results show considerable improvement with respect to previous potentials, like VWN or BP86, at least for the carbon, nitrogen, oxygen, and fluorine chemical shifts. Furthermore, a few NMR calculations carried out on third period atoms (S, P, and Cl) improved when using the SAOP potential

Management of diplopia secondary to neurosurgical injury of the orbital roof

BACKGROUND: Diplopia related to neurosurgical procedures is often consecutive to oculomotor nerve lesions. We hereby report an oculomotor dysfunction secondary to an orbital roof effraction and its treatment. HISTORY AND SIGNS: Following surgery for a left anterior communicating artery aneurysm, a 45-year-old woman reported vertical diplopia associated with a left orbital hematoma. The diagnosis of third cranial nerve palsy was excluded by orbital imaging which revealed an orbital roof defect with incarceration of the levator palpebrae and superior rectus. THERAPY AND OUTCOME: As neurosurgeons advised against muscle adhesiolysis, diplopia was corrected by a two-step procedure on the oculomotor muscles. We first corrected horizontal and torsional deviations by operating on the healthy eye, before correcting the vertical deviation on the fellow eye. This two-step extraocular muscle surgery allowed restoration of binocular single vision in a useful field of gaze. CONCLUSIONS: Diplopia can occur as a rare orbital complication during neurosurgical procedures. Surgery of extraocular muscles can provide good functional results

Reconstruction fronto-orbitaire complexe avec prothèse en PEEK et expansion cutanée : à propos d'un cas [Complex fronto-orbital reconstruction with a PEEK prosthesis and skin expansion: about a case].

INTRODUCTION: Reconstructions of the fronto-orbital area remain a challenge to the reconstructive surgeon, due to the functional and esthetic impact. OBSERVATION: The authors present a case of a complex fronto-orbital reconstruction with a PEEK (PolyEtherEtherKetone) implant, associated with a skin expansion. DISCUSSION: With a follow-up of over three years, the cosmetic result is excellent. The authors believe that this technique is reliable, fast with long-term good results.

La thérapie actuelle du rhabdomyosarcome orbitaire de l'enfant [Update of orbital rhabdomyosarcoma therapy in children]

INTRODUCTION: Rhabdomyosarcoma is the most frequent primitive orbital malignant tumor in children. If the treatment is started as soon as possible after discovery of the disease, the vital prognosis is considerably better than otherwise. The goal of this paper is to present the new therapeutic protocol and to report our experience in this field. MATERIAL AND METHOD: During the past 35 years, 102 cases of orbital tumors were collected in children under 15 years of age: 5 cases of rhabdomyosarcoma were cared for in our department. At the time of tumor diagnosis, the age of our patients ranged from 3 weeks to 13 years. After a biopsy or excision biopsy, all our cases were treated by chemotherapy with or without radiotherapy. Medication was mostly vincristine, ifosfamide and actinomycine D. When the result of the treatment was not satisfactory, carboplatine and epirubicine, vincristine as well as ifosfamide were given. Radiotherapy was performed only in particular cases or in recurrences. CONCLUSION: Rhabdomyosarcoma is a highly malignant tumor. Although rare, it is the most frequent of malignant tumors in children. It is important to keep it in mind in order to perform a biopsy enabling quick diagnosis and treatment following the modern protocol giving the highest chances of survival to these patients: about 98% in 3 years.

Metodologia para reconhecimento de três solos por sensores: laboratorial e orbital

O presente trabalho teve como objetivo estabelecer um método para a utilização de dados espectrais, obtidos em laboratório e imagens do Landsat 5, no reconhecimento e discriminação de três classes de solos do estado de São Paulo. Foram coletadas amostras de solo e obtidos os dados de reflectância por espectrorradiômetro em laboratório como padrão de um Latossolo Vermelho distroférrico (LVdf), um Argissolo Vermelho-Amarelo (PVA) e Neossolo Quartzarênico (RQ). Foram extraídos dados de reflectância das imagens, com os quais se efetuou a classificação digital pelo classificador Spectral Angular Mapper. As curvas espectrais obtidas por espectrorradiômetro em laboratório mostraram três padrões distintos de comportamento espectral, baseados nas diferenças da forma das curvas, feições de absorção dos minerais do solo e na intensidade de reflectância. O LVdf apresentou menor albedo em virtude da textura argilosa e maiores teores de Fe, ao contrário dos solos mais arenosos PVA e RQ. As bandas de absorção características da caulinta (2.200 nm), OH- e água (1.400 e 1.900 nm) ocorreram em todos os solos. Solos arenosos, como o RQ, apresentaram uma curva espectral com tendência positiva. A linha do solo mostrou distinção espectral, tanto com dados orbitais como terrestres, indicando que cada solo tem uma tendência individual. Os padrões espectrais obtidos em laboratório foram importantes para a eficiência do método na detecção dos mesmos nas imagens de satélite. Os solos avaliados podem ser discriminados e reconhecidos pela interpretação quantitativa em imagens. O método mostrou-se eficiente como auxílio no mapeamento de solos no nível semidetalhado de alta intensidade.

Diffusion-weighted spectroscopy: a novel approach to determine macromolecule resonances in short-echo time 1H-MRS.

Quantification of short-echo time proton magnetic resonance spectroscopy results in >18 metabolite concentrations (neurochemical profile). Their quantification accuracy depends on the assessment of the contribution of macromolecule (MM) resonances, previously experimentally achieved by exploiting the several fold difference in T(1). To minimize effects of heterogeneities in metabolites T(1), the aim of the study was to assess MM signal contributions by combining inversion recovery (IR) and diffusion-weighted proton spectroscopy at high-magnetic field (14.1 T) and short echo time (= 8 msec) in the rat brain. IR combined with diffusion weighting experiments (with δ/Δ = 1.5/200 msec and b-value = 11.8 msec/μm(2)) showed that the metabolite nulled spectrum (inversion time = 740 msec) was affected by residuals attributed to creatine, inositol, taurine, choline, N-acetylaspartate as well as glutamine and glutamate. While the metabolite residuals were significantly attenuated by 50%, the MM signals were almost not affected (< 8%). The combination of metabolite-nulled IR spectra with diffusion weighting allows a specific characterization of MM resonances with minimal metabolite signal contributions and is expected to lead to a more precise quantification of the neurochemical profile.

Quantification of brain glycogen concentration and turnover through localized 13C NMR of both the C1 and C6 resonances.

We have recently shown that at isotopic steady state (13)C NMR can provide a direct measurement of glycogen concentration changes, but that the turnover of glycogen was not accessible with this protocol. The aim of the present study was to design, implement and apply a novel dual-tracer infusion protocol to simultaneously measure glycogen concentration and turnover. After reaching isotopic steady state for glycogen C1 using [1-(13)C] glucose administration, [1,6-(13)C(2)] glucose was infused such that isotopic steady state was maintained at the C1 position, but the C6 position reflected (13)C label incorporation. To overcome the large chemical shift displacement error between the C1 and C6 resonances of glycogen, we implemented 2D gradient based localization using the Fourier series window approach, in conjunction with time-domain analysis of the resulting FIDs using jMRUI. The glycogen concentration of 5.1 +/- 1.6 mM measured from the C1 position was in excellent agreement with concomitant biochemical determinations. Glycogen turnover measured from the rate of label incorporation into the C6 position of glycogen in the alpha-chloralose anesthetized rat was 0.7 micromol/g/h.

Comportamento espectral dos solos na paisagem a partir de dados coletados por sensores terrestre e orbital

Parte da variabilidade dos índices de produção agrícola está associada com as características do solo e da paisagem. Dessa forma, práticas de manejo, como a adubação, devem levar em consideração esta variabilidade. O sensoriamento remoto é uma ferramenta que pode fornecer, de maneira rápida, informações para o manejo do solo, pois relaciona a radiação eletromagnética com os atributos do solo. Assim, este trabalho teve como objetivo avaliar o comportamento espectral, em dois níveis de aquisição de dados (terrestre e orbital), de diferentes classes de solos ao longo de toposseqüências na região de São Carlos e Ibaté, SP. Para isso, amostras de terra georreferenciadas foram coletadas em 319 pontos, em três profundidades. Em seguida, obtiveram-se os dados radiométricos em laboratório, na faixa espectral entre 450 e 2.500 nm. Os mesmos locais amostrados na camada superficial, no campo, foram avaliados na imagem de satélite. A partir dos resultados obtidos, pode-se concluir que: (a) teores de areia grossa, argila e matéria orgânica, e cor tiveram relação com a reflectância dos solos; (b) ao longo das vertentes ocorrem variações nos dados espectrais dos solos; e (c) solos da mesma ordem taxonômica, porém com classes texturais diferentes, apresentam diferentes comportamentos espectrais, podendo ser discriminados por sensoriamento remoto.