Imaging Prostate Cancer with SQUID-Detected Microtesla MRI

使用 SQUID 检测的微特斯拉 MRI 对前列腺癌进行成像

• 批准号: 7448743
• 负责人: John Clarke
• 金额: $ 20.88万
• 依托单位: UNIVERSITY OF CALIF-LAWRENC BERKELEY LAB
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-04-04 至 2010-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7448743
• 关键词: Affect; Agreement; Atrophic; Benign; Biopsy; Blinded; Brachytherapy; Cancerous; Clinical; Compatible; Comprehensive Cancer Center; Copper; Data; Detection; Development; Diagnosis; Diagnostic Neoplasm Staging; Disease; Electronics; Ensure; Facility Construction Funding Category; Frequencies; Future; Gel; Gland; Gleason Grade for Prostate Cancer; Goals; Histocompatibility Testing; Histology; Histopathology; Hyperplasia; Image; Image Guided Biopsy; Imaging Phantoms; Imaging Techniques; Imaging technology; In Situ; Inflammation; Location; Magnetic Resonance Imaging; Malignant Neoplasms; Malignant neoplasm of prostate; Maps; Measurement; Medical Surveillance; Metals; Methods; Molds; Monitor; Noise; Normal tissue morphology; Nuclear Magnetic Resonance; Numbers; Operative Surgical Procedures; Organ; Patient Monitoring; Patient observation; Patients; Performance; Peripheral; Placement; Primary Carcinoma; Procedures; Prostate; Prostatic Neoplasms; Prosthesis; Protocols documentation; Protons; Public Health; Radioactive Seed Implantation; Rate; Recurrence; Relaxation; Research; Research Infrastructure; Resolution; Seeds; Sensitivity and Specificity; Sepharose; Shapes; Signal Transduction; Source; Specificity; Specimen; Squid; Staging; System; Techniques; Technology; Testing; Three-Dimensional Image; Three-Dimensional Imaging; Time; TimeLine; Tissues; Tumor Tissue; Ultrasonography; Water; Weight; base; cancer imaging; clinical application; cryogenics; density; design; detector; expectation; improved; in vivo; magnetic field; magnetic resonance spectroscopic imaging; novel; prototype; research study; sensor; size; superconducting quantum interference device; tumor; tumor progression

DESCRIPTION (provided by applicant): Conventional magnetic resonance imaging (MRI) at 1.5 tesla and above is used increasingly for the detection, diagnosis and staging of cancer. In the case of prostate cancer, however, conventional MRI does not provide sufficient specificity for detection of prostate tumors. To take advantage of the enhanced T1 (longitudinal relaxation time) contrast available at low magnetic fields, a novel MRI system has been developed at LBNL which acquires MR images at microtesla fields, comparable to the Earth's field. In this technique, prepolarization of the proton spins in a much higher magnetic field is combined with detection of the nuclear magnetic resonance signal using a Superconducting QUantum Interference Device (SQUID) to enhance the signal-to-noise ratio. Preliminary data on ex vivo prostate specimens indicate that there is significantly enhanced contrast between prostate tumors and healthy prostate tissue. The goal of the proposed project is to assess the potential of this novel MR imaging method for the diagnosis and staging of prostate cancer. In a blinded study on ex vivo prostate specimens we will determine the T1 contrast in images of specimens containing different types of benign prostate tissue and tumors with various Gleason grades and compare the results with those from histopathology performed at the UCSF Comprehensive Cancer Center. In addition, we will improve the sensitivity of the SQUID detector and increase the magnitude of the polarizing field in our current imaging system to assess the spatial resolution and the signal to noise and contrast to noise ratios achievable with a future in vivo imaging system. To attain these goals we propose the following specific aims: Aim 1. Upgrade the detector sensitivity. Aim 2. Determine T1 contrast in images of ex vivo prostate tissue containing tumors and other prostate tissue types to determine the sensitivity and specificity for detecting prostate cancer. Aim 3. Design and build a polarizing coil suitable for in vivo imaging. Aim 4. Image three-dimensional (3D) prostate phantoms and compare the resolution with results predicted by calculations; image 2D ex vivo prostate specimens at a distance corresponding to that for in vivo imaging. Provided these experiments confirm the preliminary measurements, a prototype system could subsequently be constructed for in vivo studies of prostate cancer. This system would potentially be less expensive and more open than conventional MRI systems, and could significantly impact the diagnosis and staging of prostate cancer. Possible applications include: (i) Imaging the prostate before a biopsy to determine the location and extent of the cancer. (ii) More accurate mapping of the location of tumors to guide biopsy. (iii) Serial imaging to determine the progression of tumors during treatment or active surveillance. (iv) In situ monitoring of focal therapies, such as placement of the seeds during brachytherapy. PUBLIC HEALTH RELEVANCE: A magnetic resonance imaging (MRI) system will be developed to demonstrate the feasibility of imaging prostate tumors in very low magnetic fields. This technique offers much higher contrast between healthy and cancerous tissue compared to conventional high-field MRI, and the system is both less confining and less expensive. Clinical applications are expected to include serial monitoring of tumors during treatment or active surveillance, image guided biopsy, and monitoring of focal therapies like brachytherapy.

描述（由申请人提供）：在1.5特斯拉及以上的常规磁共振成像（MRI）越来越多地用于癌症的检测，诊断和分期。然而，在前列腺癌的情况下，常规MRI不能为检测前列腺肿瘤提供足够的特异性。为了利用在低磁场上可用的增强的T1（纵向松弛时间）对比度，在LBNL上已经开发了一种新型的MRI系统，该系统在Microtesla磁场上获得了MR图像，与地球场相当。在此技术中，使用超导量子干扰装置（Squid）将质子旋转的前极化与检测核磁共振信号相结合，以提高信号噪声比率。关于离体前列腺标本的初步数据表明，前列腺肿瘤和健康前列腺组织之间的对比度显着增强。拟议项目的目的是评估这种新颖的MR成像方法在前列腺癌诊断和分期的潜力。在一项针对离体前列腺样本的盲目研究中，我们将确定包含不同类型的良性前列腺组织和具有各种Gleason等级的样品图像中的T1对比度，并将结果与​​在UCSF综合癌症中心进行的组织病理学的结果进行比较。此外，我们将提高鱿鱼探测器的灵敏度，并增加当前成像系统中极化场的大小，以评估空间分辨率以及与噪声的信号以及与未来的体内成像系统可达到的噪声比对比。为了实现这些目标，我们提出以下特定目标：目标1。升级检测器的敏感性。 AIM 2。确定含有肿瘤和其他前列腺组织类型的离体前列腺组织图像中的T1对比度，以确定检测前列腺癌的敏感性和特异性。 AIM 3。设计并构建适合体内成像的偏振线圈。 AIM 4。图像三维（3D）前列腺幻象，并将分辨率与计算预测的结果进行比较；图像2D离体前列腺标本的距离与体内成像相对应的距离。只要这些实验证实了初步测量，可以随后为前列腺癌的体内研究构建原型系统。该系统可能比常规MRI系统更便宜，更开放，并且可能会显着影响前列腺癌的诊断和分期。可能的应用包括：（i）在活检前对前列腺进行成像以确定癌症的位置和程度。 （ii）更准确地映射肿瘤的位置以引导活检。 （iii）串行成像以确定治疗或主动监测过程中肿瘤的进展。 （iv）原位监测局灶性疗法，例如近距离放射治疗期间种子的放置。 公共卫生相关性：将开发一种磁共振成像（MRI）系统，以证明在非常低的磁场中成像前列腺肿瘤的可行性。与传统的高场MRI相比，该技术在健康组织和癌组织之间提供了更高的对比度，并且该系统既限制又较低。预计临床应用包括在治疗或主动监测过程中对肿瘤的连续监测，图像指导的活检以及对近距离肌疗法等局灶性疗法的监测。