Microcoil

Abstract: The optical microfiber coil resonator with self-coupling turns is suggested and investigated theoretically. This type of a microresonator has a three-dimensional geometry and complements the well-known Fabry-Perot (one-dimensional geometry, standing wave) and ring (two-dimensional geometry, traveling wave) types of microresonators. The coupled wave equations for the light propagation along the adiabatically bent coiled microfiber are derived. The particular cases of a microcoil having two and three turns are considered. The effect of microfiber radius variation on the value of Q-factor of resonances is studied.

Abstract: The use of devices in procedures, especially medical procedures where the events take place under view of Magnetic Resonance Imaging (MRI) systems is becoming more important. Although some general and specific structures have been discussed in the literature and commercialized, little has been done effectively to design devices for MRI procedures for specific tasks. The present invention describes a device for use within an organism, said device comprising an element having at least one pair of opposed RF receiver microcoils having a space between each microcoil of said pair of microcoils, the coils of said microcoils may have diameters of less than 2.4 mm. The device may also comprise an element having at least one pair of opposed RF receiver microcoils having a space between each microcoil of said pair of microcoils, said RF receiver microcoils each comprising at least three individual coils, said at least three individual coils of said microcoils having spacing between adjacent microcoils so that spacing between at least two pairs of individual coils within said microcoils differ by at least 10%. Circuitry may be insulated within the device by providing the wires and circuits within different layers in a coaxial layering of components within the catheter. The device may also comprise device an element having at least one pair of opposed RF receiver microcoils having a space between each microcoil of said pair of microcoils, the RF receiver microcoils each comprising at least three individual windings, the at least three individual windings of said microcoils having spacing between adjacent windings so that spacing between at least two pairs of individual windings within the microcoils differ by at least 10%.

Abstract: Purpose: To prospectively assess the safety and effectiveness of computed tomography (CT)-guided placement of fiber-coated microcoils used to guide video-assisted thoracoscopic surgical (VATS) excision of small peripheral lung nodules, with successful excision as the primary outcome and successful CT-guided microcoil placement and procedural complications as secondary outcomes. Materials and Methods: The institutional review board approved the study protocol. Informed consent was obtained from all 69 enrolled patients (30 men, 39 women; mean age, 60.7 years ± 10.1 [standard deviation]) with 75 nodules. At CT, one end of an 80-mm long, 0.018-inch-diameter fiber-coated microcoil was placed deep to the small peripheral lung nodule, and the other end was coiled in the pleural space. VATS excision of lung tissue, nodules, and the microcoil was performed with fluoroscopic guidance. Results: Seventy-three (97%) 4–24-mm nodules were successfully removed at fluoroscopically guided VATS excision; two nodules could ...

Abstract: We present the design, fabrication and test of high-Q factor radiofrequency planar microcoils for nuclear magnetic resonance (NMR) spectroscopy in small volume samples. The coils are fabricated on glass wafers using high-aspect ratio SU-8 photoepoxy and copper electroplating. On-wafer electrical characterization shows quality factors up to 40 at 800 MHz. A 500 μm diameter microcoil with a measured quality factor of 24 at 300 MHz is mounted on a printed circuit board and electrically contacted using aluminum wire bonding. This probe is inserted in a 7 T-superconducting magnet, and a 1H-NMR spectrum of 160 nl ethylbenzene contained in a capillary placed over the microcoil is acquired in a single scan. This work is an important step towards the integration of NMR detection into micro-total analysis systems (μTAS).