A generalized foundry-oriented CMOS-MEMS platform well suited for integrated micromechanical resonators alongside IC amplifiers has been developed for commercial multi-user purpose and demonstrated with a fast turnaround time of only 3 months and a variety of design flexibilities for resonator applications. With this platform, different configurations of capacitively-transduced resonators monolithically integrated with their amplifier circuits, spanning frequencies from 500 kHz to 14.5 MHz, have been realized with resonator Q's ranging between 700 and 3500. This platform, specifically featured with various configurations of structural materials, multi-dimensional displacements, different arrangements of mechanical boundary conditions, tiny supports of resonators, large transduction areas, well-defined anchors and performance enhancement scaling with IC fabrication technology, offers a variety of flexible design options targeted for sensor, timing reference, and RF applications. In addition, resonators consisting of metal-oxide composite structures fabricated by this platform offer an effective temperature compensation scheme for the first time in CMOS-MEMS resonators, showing TCf six times better than that of resonators merely made by CMOS metals.

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Laminotomy and transforaminal lumbar interbody fusion (TLIF) is usually used to treat unstable spinal stenosis. Minimally invasive surgery (MIS) can cause less muscle injury than conventional open surgery (COS). The purpose of this study was to compare the degree of postoperative fatty degeneration in the paraspinal muscles and the spinal decompression between COS and MIS based on MRI. Fortysix patients received laminotomy and TLIF (21 COS, 25 MIS) from February 2016 to January 2017 were included in this study. Lumbar MRI was performed within 3 months before surgery and 1 year after surgery to compare muscle-fat-index (MFI) change of the paraspinal muscles and the dural sac cross-sectional area (DSCAS) change. The average MFI change at L2-S1 erector spinae muscle was significantly greater in the COS group (27.37 ± 21.37% vs. 14.13 ± 19.19%, P = 0.044). A significant MFI change difference between the COS and MIS group was also found in the erector spinae muscle at the caudal adjacent level (54.47 ± 37.95% vs. 23.60 ± 31.59%, P = 0.016). DSCSA improvement was significantly greater in the COS group (128.15 ± 39.83 mm 2 vs. 78.15 ± 38.5 mm 2 , P = 0.0005). COS is associated with more prominent fatty degeneration of the paraspinal muscles. Statically significant post-operative MFI change was only noted in erector spinae muscle at caudal adjacent level and L2-S1 mean global level. COS produces a greater area of decompression on follow up MRI than MIS with no statistical significance on clinical grounds. Lumbar spinal fusion with conventional open surgery (COS) is an effective method to relieve the symptoms of spinal stenosis and instability. However, COS is associated with extensive iatrogenic paraspinal muscle injury due to direct muscle dissection, denervation, and ischemia during long hours of muscle retraction. The paraspinal muscles, especially the multifidus and erector spinae muscles, are essential for carrying physiological loads and functional movement, and play an important role in the stability of the lumbar spine 1. Muscle atrophy after COS occurs frequently, and can result in back pain and failed back surgery syndrome 2. Therefore, minimally invasive surgery (MIS) techniques for lumbar spine fusion have become popular because they avoid long incisions and reduce muscle injury 1,3,4. However, few studies have examined the differences of postoperative paraspinal muscle changes and outcomes between COS and MIS.

This study demonstrates the torque-enhancement design for a 2-axis magnetostatic SOI scanner driven by a double-side electroplating ferromagnetic film. The present design has two merits: (1) the slender ferromagnetic material patterns with higher length-to-width ratio enhance the magnetization, (2) the backside electroplating of the ferromagnetic film increases the volume of the ferromagnetic materials. This study also establishes the fabrication processes to implement the proposed design. The processes also have two merits: (1) the handle-layer of the SOI wafer is exploited as the shadow mask to pattern the seed-layer at the backside of the device layer, (2) the device layer of the SOI wafer acts as the cathode to enable simultaneous double-side electroplating. In applications, a 2-axis SOI scanner was implemented and characterized. Measurements show a 149% torque enhancement from the double-side electroplating design. The vertical slender ferromagnetic material patterns further increase the magnetostatic torque to 211%. This study also successfully demonstrates the Lissajous scanning using the presented 2-axis SOI scanner.

Understanding ocular complications after spinal surgery is vital. Although rare, but the most troublesome complication is ischemic orbital compartment syndrome.

BackgroundVertebral compression fractures (VCFs) constitute a major health care problem, not only because of their high incidence but also because of their direct and indirect negative impacts on both patients’ health-related quality of life and costs to the health care system. Two minimally invasive surgical approaches were developed for the management of symptomatic VCFs: balloon kyphoplasty and vertebroplasty. The purpose of this study was to evaluate the effectiveness and safety of balloon kyphoplasty in the treatment of symptomatic VCFs.MethodsBetween July 2011 and June 2012, one hundred and eighty-seven patients with two hundred and fifty-one vertebras received balloon kyphoplasty in our hospital. There were sixty-five male and one hundred and twenty-two female patients with an average age of 74.5 (range, 61 to 95 years). The pain symptoms and quality of life, were measured before operation and at one day, three months, six months and one year following kyphoplasty. Radiographic data including restoration of kyphotic angle, anterior vertebral height, and any leakage of cement were defined.ResultsThe mean visual analog pain scale decreased from a preoperative value of 7.7 to 2.2 at one day (p < .05) following operation and the Oswestry Disability Index improved from 56.8 to 18.3 (p < .05). The kyphotic angle improved from a mean of 14.4° before surgery to 6.7° at one day after surgery (p < .05). The mean anterior vertebral height increased significantly from 52% before surgery to 74.5% at one day after surgery (p < .05) and 70.2% at one year follow-up. Minor cement extravasations were observed in twenty-nine out of two hundred and fifty-one procedures, including six leakage via basivertebral vein, three leakage via segmental vein and twenty leakage through a cortical defect. None of the leakages were associated with any clinical consequences.ConclusionsBalloon kyphoplasty not only rapidly reduced pain and disability but also restored sagittal alignment in our patients at one-year follow-up. The treatment of osteoporotic vertebral compression fractures with balloon kyphoplasty is a safe, effective, and minimally invasive procedure that provides satisfactory clinical results.

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A fully differential CMOS-MEMS oxide resonator fabricated using 0.18 μm CMOS-MEMS platform via metal wetetching post process has been demonstrated with Q > 10,000, first time ever in any CMOS-MEMS resonators, and more than 25 dB signal-to-feedthrough ratio at 47.9 MHz. Key to attaining such performance attributes to (1) the bulk-mode vibration to enable exceptional Q and much higher frequencies and (2) the oxide-rich structure with embedded metal electrodes for capacitive transduction, where SiO 2 offers better mechanical properties than metals to minimize intrinsic energy loss and where flexible electrical routing facilitates fully differential configuration to suppress capacitive feedthroughs. In addition, a previously developed metal wet-etching technique capable of releasing large device areas has been successfully transferred from 0.35 μm 2-Poly-4-Metal (2P4M) CMOS process to a new 0.18 μm 1-Poly-6-Metal (1P6M) technology node, therefore greatly lowering the motional impedance of the capacitivelytransduced resonators due to smaller electrode-to-resonator gap spacing and larger transduction areas. This technology paves a way to realize fully-integrated CMOS-MEMS oscillators and filters which might benefit future single-chip transceivers for wireless communications.