Tissue Splitting Biopsy Needle

Abstract

Tissue splitting biopsy devices and methods use a needle portion and a sheath portion that are configured such as to allow simultaneous sectioning of a tissue to produce two tissue samples with corresponding surfaces using motion of the needle portion relative to the sheath portion. Most preferably, the needle portion has a chisel blade tip and at least two cavities opposite to each other and at the same distance from the tip, while the sheath portion has a sharpened front edge.

Description

[0001]This application claims priority to our copending U.S. provisional patent application with the Ser. No. 60 / 982,686, filed Oct. 25, 2007, and which is incorporated by reference herein.FIELD OF THE INVENTION[0002]The field of the invention is medical devices, especially as it relates to biopsy needles that produce multiple adjacent tissue samples.BACKGROUND[0003]Biopsies are often indispensable tools for accurate diagnosis and / or staging of a disease as blood-based tests typically provide only indirect evidence of tissue status, and current imaging analysis often lacks sufficient resolution and information density.[0004]Most commonly, a biopsy is performed using a biopsy gun in which one or more needles are advanced into the target tissue, typically under ultrasound or MRI guidance. A typical biopsy needle and gun is described in U.S. Pat. No. 5,971,939. Where desired, sample acquisition and movement may be assisted using vacuum in the needle as illustrated in U.S. Pat. No. 5,02...

AI Technical Summary

Benefits of technology

[0018]Various objects, features, aspects and advantages of the inventive subject matter will become more apparent from the following

Problems solved by technology

Biopsies are often indispensable tools for accurate diagnosis and / or staging of a disease as blood-based tests typically provide only indirect evidence of tissue status, and current imaging analysis often lacks sufficient resolution and information density.

Furthermore, where a definition or use of a term in an incorporated reference is inconsistent or contrary to the definition of that term provided herein, the definition of that term provided herein applies and the definition of that term in the reference does not apply.

Unfortunately, the processing steps for visual analysis of tissue (e.g., fixation, paraffin embedding, and staining) and molecular biological analysis of tissue (e.g., in-situ PCR, fluorescence in-situ hybridization, etc.) are in many cases incompatible and thus require multiple tissue samples to be taken from the area under investigation.

While such devices advantageously allow collection of multiple samples from a single area, various disadvantages nevertheless remain.

For example, where a malignancy is relatively small or distributed irregularly across a tissue (e.g., various malignancies in the prostate), the collected samples often fail to be co-located in the same area of interest.

Therefore, the above devices often fail to provide consistent and representative samples.

The same difficulties exist in still further known devices where multiple biopsies can be taken serially through a single sample window or needle with a flexible retractable tip cover as disclosed in U.S. Pat. No. 6,149,607 and WO2007 / 021903A2, and U.S. Pat. No. 7,137,956, respectively.

While such devices allow collection of multiple samples in multiple areas of interest, samples produced with these devices typically fail to produce tissue of the same area of interest.

While such devices and methods at least conceptually produce two samples from the same location, numerous difficulties nevertheless remain.

Most significantly, as the tissue is forced through the lumen of the cannula or needle, tissue distortion due to friction along the inside of the cannula or needle, and / or compression due to the added volume of the blade / separator structure will occur and lead to loss of tissue and tissue integrity, which is particularly pronounced in the device of the '265 application as the inner lumen is significantly smaller than the cutting tip lumen.

However, such post-harvest splitting requires considerable expertise and equipment typically not available in the clinic at which the biopsy is taken.

Moreover, even where great care is taken to split the biopsy core equally, consistent splitting is rarely achieved throughout the entire length of the core.

Therefore, while numerous devices and methods for biopsies are known in the art, all or almost all of them suffer from one or more disadvantages.

Most significantly, correlation of the corresponding areas is typically not possible as non-adjacent surfaces are generally obtained in such devices and methods.

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