Rotational needle insertion is commonly used in needle biopsy to improve cutting performance. The application of rotational motion for needle insertion has been shown to efficiently reduce the cutting force. However, studies have found that needle rotation can increase tissue damage due to the tissue winding effect. The bidirectional rotation of a needle during insertion can be a solution to avoid tissue winding while maintaining a low cutting force. In this study, needle insertion with bidirectional rotation was investigated by conducting mechanical and optical experiments. First, needle insertion tests were performed on gelatin-based tissue phantom samples to understand the effect of bidirectional needle rotation on the cutting force. Subsequently, the effective strain, which is an indicator of tissue damage, was observed at the cross-sections of samples in the axial and radial directions of the needle by using the digital image correlation (DIC) technology. The primary findings of this study are as follows: (1) higher needle insertion speeds result in higher cutting forces and effective strains that occur at the axial cross-section, (2) increase in the needle rotation reduces the cutting force and effective strain at the axial cross-section but increases the effective strain at the radial cross-section, (3) application of bidirectional rotation decreases the mean effective strain at the radial cross-section by 10%–25% while maintaining a low cutting force. In clinical applications, bidirectional rotation can be a useful strategy to simultaneously reduce the cutting force and tissue damage, which leads to better cutting performance and lower risks of bleeding and hematoma.

中文翻译：

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旋转进针同时减少切削力和组织损伤

旋转针插入常用于针活检以提高切割性能。已经证明，针插入的旋转运动的应用可以有效地降低切割力。然而，研究发现，由于组织缠绕效应，针旋转会增加组织损伤。在插入期间针的双向旋转可以是避免组织缠绕同时保持低切割力的解决方案。在这项研究中，通过进行机械和光学实验研究了双向旋转的针插入。首先，对基于明胶的组织模型样本进行了针插入测试，以了解双向针旋转对切割力的影响。随后，作为组织损伤指标的有效应变，通过使用数字图像相关（DIC）技术在针的轴向和径向方向上的样品横截面观察到。本研究的主要发现如下：(1) 较高的针插入速度会导致轴向横截面处出现更高的切削力和有效应变，(2) 针旋转的增加降低了轴向截面处的切削力和有效应变。 (3) 双向旋转使径向截面的平均有效应变降低 10%–25%，同时保持较低的切削力。在临床应用中，双向旋转是一种有用的策略，可以同时减少切割力和组织损伤，