Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY, USA.
BJU Int. 2014 Jun;113(6):977-85. doi: 10.1111/bju.12335. Epub 2013 Dec 2.
To study the feasibility and safety of using a magnetic resonance imaging (MRI)-safe robot for assisting MRI-guided transrectal needle placement and biopsy in the prostate, using a canine model. To determine the accuracy and precision afforded by the use of the robot while targeting a desired location in the organ.
In a study approved by the Institutional Animal Care and Use Committee, six healthy adult male beagles with prostates of at least 15 × 15 mm in size at the largest transverse section were chosen for the procedure. The probe portion of the robot was placed into the rectum of the dog, images were acquired and image-to-robot registration was performed. Images acquired after placement of the robot were reviewed and a radiologist selected targets for needle placement in the gland. Depending on the size of the prostate, up to a maximum of six needle placements were performed on each dog. After needle placement, robot-assisted core biopsies were performed on four dogs that had larger prostate volumes and extracted cores were analysed for potential diagnostic value.
Robot-assisted MRI-guided needle placements were performed to target a total of 30 locations in six dogs, achieving a targeting accuracy of 2.58 mm (mean) and precision of 1.31 mm (SD). All needle placements were successfully completed on the first attempt. The mean time required to select a desired target location in the prostate, align the needle guide to that point, insert the needle and perform the biopsy was ∼ 3 min. For this targeting accuracy study, the inserted needle was also imaged after its placement in the prostate, which took an additional 6-8 min. Signal-to-noise ratio analysis indicated that the presence of the robot within the scanner bore had minimal impact on the quality of the images acquired. Analysis of intact biopsy core samples indicated that the samples contained prostatic tissues, appropriate for making a potential diagnosis. Dogs used in the study did not experience device- or procedure-related complications.
Results from this preclinical pilot animal study suggest that MRI-targeted transrectal biopsies are feasible to perform and this procedure may be safely assisted by an MRI-safe robotic device.
使用一种经磁共振成像（MRI）安全认证的机器人辅助 MRI 引导经直肠前列腺穿刺活检，在犬模型中研究其可行性和安全性。确定在靶向器官目标位置时使用机器人的准确性和精密度。
在机构动物护理和使用委员会批准的一项研究中，选择了 6 只具有至少 15×15mm 大小的前列腺的健康成年雄性比格犬进行该程序。将机器人的探头部分放入犬的直肠中，采集图像并进行图像到机器人的配准。对放置机器人后的图像进行审查，由放射科医生选择在腺体内进行针放置的目标。根据前列腺的大小，每只犬最多可进行 6 次针放置。在进行针放置后，对 4 只前列腺体积较大的犬进行机器人辅助核心活检，并对提取的核心进行潜在诊断价值分析。
总共在 6 只犬中进行了 30 次机器人辅助 MRI 引导的针放置，目标定位精度为 2.58mm（平均值），精度为 1.31mm（标准差）。所有针放置均首次成功完成。选择前列腺中所需目标位置、将针引导器对准该点、插入针和进行活检所需的平均时间约为 3 分钟。对于这项靶向精度研究，在将针插入前列腺后还对其进行了成像，这又额外花费了 6-8 分钟。信噪比分析表明，机器人在扫描孔内的存在对采集图像的质量几乎没有影响。对完整活检芯样本的分析表明，样本包含前列腺组织，适合进行潜在诊断。用于研究的犬未经历与设备或程序相关的并发症。
这项临床前动物研究的结果表明，MRI 靶向经直肠活检是可行的，并且该程序可以由经 MRI 安全认证的机器人设备安全辅助。
