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resources:p2:start [2014/01/13 17:29] – mouradaresources:p2:start [2014/01/15 18:30] – egz
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 Figure 1. (a) Effect of supperfluidity of water around spherical sperparamagnetic NPs.(b) fluid properties in absence of magnetic effects Figure 1. (a) Effect of supperfluidity of water around spherical sperparamagnetic NPs.(b) fluid properties in absence of magnetic effects
  
-====== Epilepsy ======+ 
 +**Nanopore** 
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 +Set-up ( which nanoseconds membrane? size of hole? monitoring? , ? (background: Physics? Coil? calculation?) chemical protocol?  
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 +====== Epilepsy ====== 
  
 MRI imaging of superparamagnetic particles and rods aggregates in the brain MRI imaging of superparamagnetic particles and rods aggregates in the brain
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 Figure 1. Schematic of  tumor detection unite Figure 1. Schematic of  tumor detection unite
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 +====== Magneto-accoustic effect for breast surgery ======
 +II. Breast surgery
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 +The therapeutic effect of focused ultrasound was known for quite a century now. Long ago, before MRI systems where made possible, there was absolutely no way to benefit from the therapeutic effect of focused  ultrasounds, for there was no  physical  way to monitor the shifts in the position of focal points of acoustic fields, especially in a human body where, waves, on there way to the target, propagate through paths of different acoustic impedance (fat, muscle, veins and glands ). The spacial shift of focal points coordinates is counterproductive and could prove lethal in cases like tumor ablation. MRI systems allow the visualization and monitoring of focal points and hence, in case of a noticeable  shift  in the coordinates, corrections of the targeting could be carried out.
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 +2.1 MRI free focused ultrasound surgery breast carcinoma
 + A totally acoustic imaging and ablation system as mentioned formerly is quiet impossible. Unless, one resorts to contrast agents to highlight tumors under an acoustic field, tumors will remain invisible for contemporary sonographs. Ultrasound contrast agents consist mainly of gas entrapping, polymeric micro capsules that reflect ultrasonic waves in a different way that differs from tissues. But gas bubbles are highly soluble in blood, conferring to the capsules, a very shot period of life within the body and  making them unsuitable for ablation applications. The development of a new technique of visualization and ablation of tumors using acoustic field exclusively is eminent and calls for a new generation of tumor markers for ultrasound imaging and new technique of focusing acoustic energy in homogeneous media, in a way that is independent of human observation and correction.           
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 +2.2 All ultrasonic detection and ablation system  of breast tumors
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 +Heterogeneity of propagation media has been studied by the navy in order to overcome the problem of object identification by sonars, in troubled waters. Phase conjugation, imported from optics (holography) allows an acoustic echo to be sent back to the source (tumor) and be focused exactly inside it, with an unprecedented resolution (smaller size of the focal points and sharper temperature profiles). The conjugation is carried out simply by recording the imaging signals (By 360 degrees matrix of piezoelectric elements), recording the echos in RAMs (digital memory) and reading it backward to create high power ultrasound waves, meant to be sent back to the tumor. The time reversal of the waves is at the core of this phase conjugation technique. Time reversal is the mere fact of reading the RAM in a reversed manner. This way, we can create a low cost, MRI free targeting system, that is portable reliable. Further more in the development phase of this system, results should be compared with the targeting power given by an MRI system. At Sait-Luc Hospital, Temperature maps (T-maps) are already running on MRI systems, a powerful tool that allowed systems developed by GE (Exablate 2000) to visualize sonication points in the breast in order to correct for the shifts introduced by inhomogeneities. T-maps are MRI sequences based on echo-planar imaging EPI, that can detect a temperature gradient of 0.01 degrees Celsius. Figure. 2, depicts the all ultrasound detection and ablation of breast tumors.
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 +{{:resources:p2:breast_surgery.jpg|}}
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 +Figure. 2, All ultrasound detection and ablation of breast tumors
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