Review: General Orientation Guidelines
- Specimens with a longer side versus width, such as core biopsies, are ideally arranged in parallel rows perpendicular to what will be the long axis of the slide.
- Larger specimens should be embedded face up or face down, making sure they lie flat and are in one plane.
- Multiple fragments of any specimen should be embedded within the same level and in a manner to show the most surface area.
- Lumen openings must be embedded in cross-section.
- Stratified layers should be embedded on edge to show all layers.
- Place at an angle any dense, rigid, or brittle specimens to aid microtomy.
- Leave a large perimeter of paraffin, especially around fatty specimens.
- Special orientation instructions are best given in relationship to the block face.
- If there are questions or concerns about orientation, it is always best to hold the specimen and ask for assistance from the grossing pathologists' assistant (PA) or pathologist to avoid losing important diagnostic information due to incorrect orientation.