Impregnation Flashcards
Enumerate advantages of impregnation (3)
✨ Easier handling
✨ Firm consistency of the specimen
✨ Cutting of suitably thin section w/o damage/distortion tothe tissue and cellular components
Types of tissue impregnation and embedding media (4)
✨Paraffin wax
✨Celloidin (collodion)
✨Gelatin
✨Plastic
The simplest, most common and best embedding medium used for routine tissue processing
Paraffin
✨how many times will you submerged a tissue in a melted paraffin wax after it has been completely cleared?
Follow-up Qs:
✨ what instrument/s will you use?
✨ regulated temp of the instrument?
✨ two or more changes
✨ paraffin oven; incubator
✨ 55-60 degrees C
Melting point of waxes (4)
✨ 45 C
✨ 52 C
✨ 56 C
✨ 58 C
temperature of wax normally used for routine work?
✨ 56 C
The process whereby the clearing agent is completely removed from the tissue and replaced by a medium that will completely fill all the tissue cavities
Impregnation (infiltration)
lab temp ranging from 20-24 C, what is the temp range of the paraffin wax?
54-58 C
lab temp ranging from 15-18 C, what is the temp range of the paraffin wax?
50-54 C
3 methods of paraffin wax impregnation and embedding
✨ Manual processing
✨ Automatic processing
✨ Vacuum embedding
For manual processing, how many mins is required in order to ensure complete removal of the clearing agent from the tissue?
15 mins (at least 4 changes)
For manual processing how many hours is needed to ensure complete embedding or casting of tissue?
3 hrs
this method makes use of an automatic tissue processing machine w/c fixes, dehydrates, clears and infiltrates tissues?
example of this machine?
✨ automatic processing
✨ Autotechnicon; Elliot bench-type processor
how many processing steps in automatic processing?
✨ 12 individual processing steps
in automatic processing, how many glass beakers are present? and what is their capacity?
✨ ten 1-liter glass beakers
moves the tissues from one processing reagent to another
transfer arm
what is the temperature of wax bath thermostats?
✨ Atleast 3°C above the melting point of the wax
process which involves the wax impregnation under negative atmospheric pressure inside an embedding oven to hasten removal of air bubbles and clearing agent to promote more rapid wax penetration of the tissue
Vacuum embedding
vacuum pressure
✨ not more than 500 mmHg (400-450 mmHg)
in vacuum embedding, what example of organ undergoes wax impregnation and removal of any residual air bubbles?
Lungs
Vacuum embedding is recommmended for (2)?
1) Urgent biopsies
2) Delicate tissues such as:
✨lung
✨brain
✨ CT
✨ decalcified bones
✨ eyes
✨spleen
✨ CNS
Factors that affects the total impregnation time (3)
✨Nature of the tissue
✨ size of the tissue
✨ type of clearing agent used
benzene and xylene are _____ removed from the tissues
easily
chloroform and cedarwood oil are _____ to remove from tissues
difficult
addition of this clearing agent may hasten displacement of cedarwood oil will less tissue shrinkage
benzene