Purpose Early detection of choroidal melanomas' relapse after conservative treatment is a challenge. Ocular echography is the main exam for the follow up of tumoral thickness, but are all the growths observed afte...
Purpose Early detection of choroidal melanomas' relapse after conservative treatment is a challenge. Ocular echography is the main exam for the follow up of tumoral thickness, but are all the growths observed after treatment reccurences? We decided to study the regression pattern of uveal melanomas after proton beam therapy to look for an association with local recurrences. Methods Our study is a retrospective study on all the patients treated by proton beam therapy at the Cyclotron of Nice between june 1991 and july 2010. Our inclusion criterias were a minimum of two echographic eight measurments after treatment and a follow up of a minimum of 6 months, exams were made by the same specialist(JPC). Results Over the 1155 patients treated, 779 encountered the inclusion criterias. The mean decrease is 8% at 6 months, 20% at 12 months and 35% at 24 months. we observed that 70% of the tumors are stable at 6 months, 50% at 12 months and only 30% at 24 months. An increase of more than 15% is encoutered in 10% of the patients at 6 months, 5 and 2,5% at 12 and 24 months. At 6 and 12 months, tumors which increase is bigger than 15% show no differences for local control. At 24 months,there is a significative difference for local control if the tumor increases(p=0,0003). Conclusion Analysis of regression pattern allows us to observe that an increase of tumoral thickness is quite usual and isn't statistically linked to local control failure if observed before 12 months. Confirmation of tumor growth is then necessary before an enucleation or a second radiotherapy. After 24 months, we found an association between recurrences and tumor growth and we need new exam to quickly confirm the diagnosis and start treatment.
A variation of the two‐tone masking technique was employed in an experiment designed to investigate the effects of stimulus intensity upon the critical band. The masker consisted of the upper and lower sidebands of a...
A variation of the two‐tone masking technique was employed in an experiment designed to investigate the effects of stimulus intensity upon the critical band. The masker consisted of the upper and lower sidebands of an AM signal with the carrier signal suppressed. The test signal was a pulsed sinusoid equal to the carrier frequency and located midway between the two maskers. The spacing between the sidebands (Δf) of the masker, the masker SPL and the location of the masker (carrier/test frequency) were parametrically varied. As the test frequency increased, a peak (increase) in the masking audiogram occurred that was dependent upon Δf and SPL. As Δf increased, this peak occurred at a higher test frequency. With Δf held constant, the peak migrated to a lower frequency with increases in masker SPL. While the traditional two‐tone masking technique generally results in critical band estimates that are dependent only upon frequency, the variation used in the present study leads to results that are dependent upon frequency and SPL.
A rigorous method for characterizing, in terms of a multimode scattering matrix, a finite array of antennas where each antenna can be described by means of spherical waves is presented in this paper. The procedure pro...
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A rigorous method for characterizing, in terms of a multimode scattering matrix, a finite array of antennas where each antenna can be described by means of spherical waves is presented in this paper. The procedure provides the impedance, coupling and radiating characteristics of the arrays and comprises two steps. First, the generalized scattering matrix (GSM) of each single antenna is numerically calculated over a wide band of frequencies. For this purpose we use a previously-developed methodology that combines the domain segmentation technique, the three-dimensional finite element method (3D-FEM), spherical mode expansion and a reduced order model obtained using a symmetric matrix Pade-Via-Lanczos (SyMPVL) algorithm. Second;the overall GSM of the finite array is calculated starting from the GSM of each antenna and using rotation and translation of spherical waves. A closed-form expression for the overall GSM is given and different examples are shown in order to validate the proposed method.
This paper analyzes and researches the CAD modeling technology of construction engineering through extended diagrams as well as polymorphic models. This paper takes the CAD model of the process plant as the main resea...
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