Admin Table of Contents
What is a biopsy cassette?
Biopsy Cassettes are designed to allow processing of the smallest specimens without the need to use foam inserts or lens paper. The rigidly constructed cassettes are made of solvent and acid resistant plastic featuring a textured writing surface on three sides. Cassette offers a 50 degree writing surface.
How do you use a tissue cassette?
Method
- Place samples in tissue cassettes.
- Immerse cassettes in 10% formalin for 12–24 hr for tissue fixation.
- Transfer cassettes to ethanol dehydration series for 45 min each in 70%, 80%, and 95% ethanol.
- Immerse cassettes in 2 changes of 100% ethanol for 45 min each.
- Clear samples in 2 changes of xylene for 45 min.
How do you label a tissue cassette?
Label cassettes: When labelling cassettes, use only a reagent resistive marker (ex: Statmark Pen) or a #2 hard lead pencil for cassettes, never a pen or Sharpie marker. Solvents used in processing can remove the ink from many “permanent” Sharpie markers.
What is automatic tissue processing?
1 Description of Function. 1.1 Tissues from the body taken for diagnosis of disease processes are processed by the tissue processor in the histology laboratory to process tissues prior to microtomy to produce microscopic slides that are viewed under the microscope by pathologists.
What are the steps of tissue processing?
Overview of the steps in tissue processing for paraffin sections
- Obtaining a fresh specimen. Fresh tissue specimens will come from various sources.
- Fixation. The specimen is placed in a liquid fixing agent (fixative) such as formaldehyde solution (formalin).
- Dehydration.
- Clearing.
- Wax infiltration.
- Embedding or blocking out.
How do they take a biopsy of the liver?
It involves inserting a thin needle through your abdomen into the liver and removing a small piece of tissue. Two other types of liver biopsy — one using a vein in the neck (transjugular) and the other using a small abdominal incision (laparoscopic) — also remove liver tissue with a needle.
How do you fix a histology tissue?
Fixation The specimen is placed in a liquid fixing agent (fixative) such as formaldehyde solution (formalin). This will slowly penetrate the tissue causing chemical and physical changes that will harden and preserve the tissue and protect it against subsequent processing steps.
What is histology used for?
Histopathology is the diagnosis and study of diseases of the tissues, and involves examining tissues and/or cells under a microscope. Histopathologists are responsible for making tissue diagnoses and helping clinicians manage a patient’s care.
What are FFPE samples?
Formalin-Fixed Paraffin-Embedded (FFPE) tissue specimens have been a staple of research and therapeutic applications for decades. FFPE is a form of preservation and preparation for biopsy specimens that aids in examination, experimental research, and diagnostic/drug development.
What is the aim of tissue processing?
1. DEFINITION : Tissue processing: The aim of tissue processing is to embed the tissue in a solid medium firm enough to support the tissue and give it sufficient rigidity to enable thin sections to be cut, and yet soft enough not to damage the knife or tissue.
What happens if liver function test is abnormal?
If blood levels of transaminases go up this suggests leakage from damaged liver cells due to inflammation or cell death. AST and ALT tend to be high in liver disease and very high in liver inflammation. ALT is mainly found in the liver. AST is also found in muscle and red blood cells.
Are liver biopsies accurate?
An experience of 97 liver biopsies performed under the guidance of a portable ultrasonographic procedure was reviewed. Of the 88 cases in which the results of biopsy were available, 73 malignant and 7 benign liver diseases were correctly diagnosed by the procedure, an accuracy of 90.9 per cent. There was no mortality.