Methods and devices for automated biopsy and collection of soft tissue

Abstract

Instruments for performing percutaneous biopsy procedures are disclosed, which have advantageous features for improving functionality and performance over prior art devices. These instruments comprise two types, single-use devices, and multiple-use devices having active tissue capture capability. Improved features include the ability to retrieve and evaluate multiple tissue samples during a single insertion procedure, without physical handling of the samples, as well as constructional features, such as a molded tissue cassette housing, variant vacuum port embodiments suited for different tissue environments, and a method for backflushing the instrument to remove biological debris, among others.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation-in-part of co-pending parent application Ser. No. 08 / 217,246, filed Mar. 24, 1994.FIELD OF THE INVENTION [0002] The present invention relates to methods and devices for tissue sampling, and more specifically to improved biopsy instruments and methods for acquiring subcutaneous biopsies and for removing lesions. BACKGROUND OF THE INVENTION [0003] It is often desirable and frequently necessary to sample or test a portion tissue from humans and other animals, particularly in the diagnosis and treatment of patients with cancerous tumors, pre-malignant conditions, and other diseases or disorders. Typically, in the case of cancer, when the physician establishes by means of procedures such as palpation, x-ray, or ultrasound imaging that suspicious circumstances exist, a biopsy is performed to determine whether the cells are cancerous. Biopsy may be done by an open or percutaneous technique. Open biopsy, which...

AI Technical Summary

Benefits of technology

[0009] This invention addresses the aforementioned needs by providing a number of important new features and innovations for the active capture type of biopsy instrument which each collectively or singly contribute to improved and more versatile operation. For example, such innovations include a molded tissue cassette housing, permitting easy and inexpensive fabrication while also permitting the handling and viewing of multiple tissue samples without physical contact by the instrument operator. The housing is interconnected with the piercing needle using a thumbwheel which permits the needle to rotate relative to the housing, thereby preventing the vacuum tube from wrapping about the housing. Several variant vacuum port embodiments are disclosed, each of which have advantages in certain tissue environments. Also disclosed is a method for backflushing biological debris from the instrument which builds up after repeated sampling procedures, without removing the instrument from the selected tissue location.

[0010] With respect to the single-use type of biopsy instrument, several tissue capture embodiments are disclosed for improving the capture process, so that complete and well preserved samples are obtained. Many of these embodiments are also applicable for use with the active capture instrument type.

[0012] Surprisingly, the inventors have found that preferably, in order to minimize tissue clogging of the cutter, the knock-out pin should have an effective diameter or cross-sectional area of at least 0.030 inches, and the ratio of the effective diameter of the knock-out pin to the internal diameter of the cannular cutter should be at least approximately one-half.

Problems solved by technology

The type of biopsy utilized depends in large part on circumstances present with respect to the patient, and no single procedure is ideal for all cases.

However, they also have disadvantages.

An important disadvantage is that the small core size makes it necessary to accurately place the needle when sampling small lesions.

This action is tedious and time consuming.

A further disadvantage of such single-use guns is the needle typically used in such a device, e.g. the True Cut® needle manufactured by Travenol Laboratories.

Unfortunately, the True Cut® needle is rough on organs and lesions, often only obtaining small fragments of tissue, and is quite operator dependent—some individuals are good at operating the device and some are not.

However, it does not operate equally well in all procedures and in all bodily environments.

Images