Low-cost handheld medical device for neuroaxial anesthesia guidance in the obese

描述(申请人提供)：目前神经轴麻手术(即硬膜外麻醉和脊麻)的护理标准是手动触诊脊柱骨标，然后进行“盲针”插入。然而，在肥胖人群中，据估计约占美国总人口的33.9%，脊柱地标被厚厚的脂肪层覆盖，通过触诊无法检测到。因此，手术失败率很高(即40%-80%)，导致许多健康并发症：头痛、血肿、背痛、血管穿刺术、胸膜穿刺术、气胸和瘫痪。盲法的替代方法包括透视和超声引导。透视缺乏便携性，成本较高，并使患者暴露在电离辐射中。最近的研究表明，传统超声波可以提高成功率(例如，成功率从32%提高到65%)。然而，由于超声对骨骼的成像质量较差，故障率仍然很高。需要新的医疗器械技术来克服标准超声的局限性，提高肥胖者的神经轴麻成功率。这项第一阶段的提案寻求资金，以支持低成本、手持医疗设备的开发和可行性测试，用于肥胖者的神经轴麻指导。该项目的关键技术创新包括具有较少数量的单元件换能器和多模式位置传感的超声系统，由于降低了设备成本、更大的便携性和减少了离轴反射伪影，该系统在技术上比标准超声波先进。此外，该项目还包括一种基于主动形状模型的骨面位置估计方法，用于自动识别针插入位置，这使得图像解释比仅使用标准超声更直观。拟议项目的长期目标是将一种便携式、低成本、基于超声波的医疗设备商业化，以降低神经轴麻手术带来的不良健康后果的风险。这项研究的第一阶段假设是，可以开发一种低成本的基于超声的手持式医学成像设备，并在体外骨骼、组织和体脂模拟体模实验中证明，在图像深度可达10厘米的情况下，骨图像分辨率优于2.5 mm。将展示一种功能强大的手持超声样机，它具有实时图像显示和15分贝的电子信噪比(SNR)，图像深度为10厘米。此外，基于模型的脊柱解剖位置估计技术将在模拟中开发，该设备将在体外模型实验中进行实验验证，以展示成像分辨率&lt；2.5 mm。第二阶段的研究计划包括工业设计、软件和用户界面开发，以及在弗吉尼亚大学医院进行的体内试验研究。据估计，美国每年进行1800万例手术，美国市场规模估计约为2.08亿美元/年，全球市场规模为5.66亿美元/年。 公共卫生相关性：目前神经轴麻手术的护理标准包括基于手动触诊脊柱骨标的盲针插入。在肥胖者中，失败率很高(即40%-80%)，因为肥胖者看不到地标，这导致了许多健康并发症：头痛、血肿、背痛、血管穿孔、胸膜穿孔、气胸和瘫痪。该项目的长期目标是展示一种便携式、低成本、基于超声波的医疗设备，该设备可以促进肥胖者的神经轴麻，提高成功率，并降低相关健康并发症的风险。

DESCRIPTION (provided by applicant): The current standard of care for neuroaxial anesthesia procedures (i.e. epidural and spinal anesthesia) is manual palpation of spinal bone landmarks followed by "blind" needle insertion. However, in the obese segment of the population, estimated at approximately 33.9% of the total US population, spinal bone landmarks are covered with thick layers of fat and are not detectable via palpation. As a result, procedure failures occur at high rates (i.e. 40% - 80%) resulting in numerous health complications: headache, hematoma, backpain, vascular puncture, pleural puncture, pneumothorax, and paralysis. Alternative approaches to the blind method include fluoroscopy and ultrasound guidance. Fluoroscopy lacks portability, has a higher cost, and exposes the patient to ionizing radiation. Recent studies have shown that conventional ultrasound improves success rates (e.g. 65% from 32%). However, failure rates remain high due to poor image quality of bone with ultrasound. New medical device technology is needed to overcome limitations of standard ultrasound and improve neuroaxial anesthesia success rates in the obese. This Phase I proposal seeks funding to support the development and feasibility testing of a low-cost, handheld medical device for neuroaxial anesthesia guidance in the obese. Key technological innovations of this project include an ultrasound system with a low number of single-element transducers and multi-modality position sensing, which is technologically advanced over standard ultrasound due to reduced device cost, greater portability, and mitigation of off-axis reflection artifacts. In addition, this project includes an active shape model-based bone surface position estimation method for automated identification of needle insertion location, which enables more intuitive image interpretation than with standard ultrasound alone. The long-term goal of the proposed project is to commercialize a portable, low-cost, ultrasound-based medical device to lower the risk of adverse health outcomes from neuroaxial anesthesia procedures. The Phase I hypothesis of the proposed research is that a low-cost handheld ultrasound-based medical imaging device can be developed and demonstrated to achieve bone image resolution better than 2.5 mm at image depths up to 10 cm in ex vivo bone, tissue, and body fat-mimicking phantom experiments. A functional handheld ultrasound prototype with real-time image display and electronic signal-to-noise ratio (SNR) from bone > 15 dB at image depths of 10 cm will be demonstrated. In addition, model-based spinal bone anatomy position estimation techniques will be developed in simulation and the device will be experimentally validated in ex vivo phantom experiments to demonstrate imaging resolution < 2.5 mm. Research plans for Phase II include industrial design, software and user interface development, and an in vivo pilot study at the University of Virginia Hospital. With an estimated 18 million procedures performed in the US per year, the estimated US market size is approximately $208 M/yr with a worldwide market of $566 M/yr. PUBLIC HEALTH RELEVANCE: The current standard of care for neuroaxial anesthesia procedures includes blind needle insertion based on manual palpation of spinal bone landmarks. Failures occur at high rates (i.e. 40% - 80%) in the obese where landmarks are impalpable, which results in numerous health complications: headache, hematoma, back pain, vascular puncture, pleural puncture, pneumothorax, and paralysis. The long-term goal of this project is to demonstrate a portable, low-cost, ultrasound-based medical device that facilitates neuroaxial anesthesia in the obese, improves success rates, and lowers the risk of associated health complications.