Clearing

• What is another name for clearing in tissue processing?

  Dealcoholization
• What is the purpose of clearing in tissue processing?

  To remove dehydrating agents and replace them with a miscible fluid
• What is the effect of over clearing on tissue?

  It causes brittleness
• What is the most common clearing agent used?

  Xylene
• What is the typical clearing time for xylene?

  15-30 minutes to 1 hour
• What is the maximum thickness for a celloidin section during clearing?

  Less than 5 mm
• How long should tissues be left in toluene for optimal results?

  1. 2 hours
• What is a key difference between toluene and xylene in terms of toxicity?

  Toluene is not carcinogenic, while xylene is considered more toxic
• What is the typical clearing time for benzene?

  15-60 minutes
• What is a significant health risk associated with benzene?

  It can cause aplastic anemia
• How long does chloroform typically take to clear tissues?

  1. 24 hours
• What is a notable characteristic of chloroform as a clearing agent?

  It is slower in action than xylene
• What is the main use of cedarwood oil in tissue processing?

  For CNS tissue and cytology
• How long does cedarwood oil take to clear tissues?

  1. 3 days
• What is the main drawback of using cedarwood oil?

  It is very expensive
• What is the primary use of aniline oil in tissue processing?

  Recommended for embryos, insects, and very delicate tissue
• What is a characteristic of clove oil as a clearing agent?

  It has minimal shrinkage
• What is the main limitation of using methyl benzoate and methyl salicylate?

  They are slow acting
• What are the uses of various clearing agents mentioned?

  • Oil of Bergamot: for skin and smooth muscle
  • Oil of Origanum: for skin
  • Oil of Wintergreen: for delicate tissues
  • Carbon Disulfide: for smooth muscle; foul odor
  • Carbol Xylene: for friable tissues
  • Terpineol: for delicate materials like eyes
  • Phenol: for smooth muscles
  • High Test Aviation: excellent clearing agent
• What is the effect of carbon tetrachloride on tissues?

  It can cause tissue hardening
• What is the typical action time for carbon tetrachloride?

  Similar to chloroform
• What is a notable characteristic of carbol xylene?

  It is used for friable tissues
• What is the primary use of terpineol in tissue processing?

  For delicate materials like eyes
• What is the main use of phenol in tissue processing?

  For smooth muscles
• What is the significance of high test aviation fuel in tissue processing?

  It is an excellent clearing agent
• How do the properties of oil of wintergreen compare to other clearing agents?

  It is an artificial oil used for delicate tissues
• What is the effect of using adulterated clove oil in tissue processing?

  It can easily become contaminated
• What is the typical duration for using chloroform as a clearing agent?

  1. 24 hours
• What is the main advantage of using benzene in tissue processing?

  It doesn't make tissues hard and brittle
• How does the action time of xylene compare to that of toluene?

  Xylene acts faster than toluene
• What is the significance of using a clearing agent that is miscible with both the dehydrating agent and the embedding medium?

  It ensures proper transition between different phases of tissue processing
• What is the effect of prolonged exposure to toluene?

  It is toxic
• Why is it important to monitor the duration of clearing agents?

  To prevent brittleness and ensure optimal tissue preservation