PAGE 2 Flashcards
ORGAN PREPARATION OF AIR-FILLED LUNGS
Cover with several layers of gauze
ORGAN PREPARATION OF HOLLOW ORGANS
✓ Dilate with cotton soaked in fixative
✓ Completely open specimen
ORGAN PREPARATION OF BRAIN
✓ Fix first before sampling
✓ Suspended by a cord tied under the Circle of Willis
✓ Intravascular perfusion using Ringer’s lactate
ORGAN PREPARATION OF EYE
✓ Fixed whole
✓ Inject formol-alcohol
TISSUE PREPARATION OF HARD TISSUES
LENDRUM’S METHOD
PROCEDURE FOR LENDRUM’S METHOD
washed out with running water overnight and immersed in 4% aq. phenol solution for 1-3 days
TISSUE PREPARATION OF MUSCLES
✓ Stretched with sutures on each end
✓ Laid flat in a moist filter paper
CHARACTERISTICS OF A GOOD FIXATIVE
- Cheap & economical
- Stable and safe to handle
- Fast acting, permits rapid an even penetration
- Inhibits bacterial decomposition & autolysis
- Must harden tissues
- At least isotonic
- Must render tissues insensitive to subsequent processing
- Must be compatible with many staining procedures
TYPES OF FIXATIVE
- ACCORDING TO COMPOSITION
2. ACCORDING TO ACTION
TYPES OF FIXATIVE ACCORDING TO COMPOSITION
- SIMPLE FIXATIVE
2. COMPUND FIXATIVE
TYPES OF FIXATIVE ACCORDING TO ACTION
- MICROANATOMICAL FIXATIVE
- CYTOLOGICAL FIXATIVE
- HISTOCHEMICAL FIXATIVE
TYPES OF CYTOLOGICAL FIXATIVE
- CYTOPLASMIC FIXATIVE
2. NUCLEAR FIXATIVE
made up of only one component substance
SIMPLE FIXATIVES
made up of two or more fixatives
COMPOUND FIXATIVES
permit general microscopic study of tissue structures and normal intercellular relationship of tissues
MICROANATOMICAL FIXATIVE
