Читать книгу Veterinary Surgical Oncology - Группа авторов - Страница 22

This technique is most effective for cutaneous lesions as well as intraoperatively for biopsies of masses within organs such as the liver, spleen, and kidney. Subcutaneous lesions can be biopsied using this method, but it is best to incise the skin overlying the mass and then obtain the sample using the biopsy instrument.

Figure 1.3 (a) Automated needle core biopsy instrument. (b) The tip of the needle has an indentation, which is filled with the tumor tissue when inserted. There is a sleeve with a cutting edge (red arrow), which cuts the piece of tissue in the indentation of the needle.

Instrumentation includes a punch biopsy instrument (Figure 1.4), which typically comes in sizes of 2, 4, 6, and 8 mm; #11 scalpel blade; local anesthetic; Metzenbaum scissors; forceps; and suture. The area containing the mass is clipped free of fur and prepared with aseptic technique. If intact skin will be penetrated and the animal is not anesthetized, the skin overlying the lesion is anesthetized with lidocaine or bupivacaine. For cutaneous masses, an incision is not necessary. For subcutaneous masses, make an incision in the skin over the mass and dissect tissues overlying the mass if present to allow for the procurement of a better sample. The skin incision should be large enough for the punch biopsy instrument to be placed and allow it to be twisted without engaging skin. Twist the punch biopsy instrument until the device is embedded into the mass to the hub. The punch biopsy instrument is then withdrawn from the mass to expose the tissue sample. Gently grasp the sample with forceps, utilize Metzenbaum scissors to sever the deep aspect of the sample from the rest of the tissue, and remove the sample. A single suture is generally sufficient to close the incision. The same procedure can be performed on visceral organs.