TROUBLESHOOTING: Cry-Ac

Problem: Trigger handle sticks open, won't stop spraying.
Solution: Rotate the trigger to the side until the next time you need to use it. If this doesn't work, depressurize it by unscrewing the top.

Problem: Excessive leaking/hissing from the relief valve.
Solution: The exterior of the Cry-Ac has too much frost built up. Try pushing down on the relief valve and twisting it back and forth to break up the ice. You can also clean the frost with alcohol and gauze.

Problem: Sprays only intermittently.

Solution: The liquid nitrogen supply may be contaminated with water. Check for cloudy droplets of ice.

Problem: Does not spray

Solution A) Trigger is too close. Twist the round silver part to adjust the trigger position.

Solution B) The Cry-Ac has been over-filled and there is insufficient air space inside the bottle to create an adequate build up of pressure required to spray. Do not fill past this line.

Solution C) Check that the rubber gasket is in place inside the cover and is not split or missing.

Solution D) The position of the trigger should be directly to the left or right of the delivery tube.

HOW TO PREP AND CUT: Biopies

Occasionally, the doctor may find a suspicious spot and will want to do a biopsy before going ahead with Mohs. Instead of the usual horizontal sectioning, biopsies are sectioned vertically. You may have heard it referred to as "bread-loafing."

A biopsy can reveal whether there are any cancer cells present and can help differentiate between the various types of cancer. It will not, however, tell you WHERE those cells are or if the margins are clear. 

There is no need to bisect or ink the tissue because you will be cutting through the entire piece. Squeeze some OCT onto a disc on the cold bar. Once the base of the OCT has turned white, hold the biopsy specimen vertically in the OCT until it's frozen enough to stand up on its own. Add more OCT on top so that none of the tissue is exposed.

Don't worry about lining it up perfectly, just eyeball it and do your best. The FBX slide must show sections from the entire specimen, so you'll be cutting through quite a bit of tissue in between the sections that you actually pick up. Advance the wheel manually several times then use the hand-crank wheel to discard a few regular cuts before picking up a nice wafer.

As always, be careful that the tissue sections are not placed on top of OCT from a previous section or it will all wash off in the stains. There won't be any tissue left to do a recut!

Repeat until you have at least 8 sections and you've cut through the entire biopsy specimen. Stain as usual.

Large Biopies
If you get a biopsy that's bigger than usual, you can save time by bisecting it and placing the halves vertically on a slide. Freeze the back of the slide and make a regular mount as if you're processing a normal mohs specimen. Since the piece is now essentially half the depth, you won't waste as much time cutting through the specimen to get your 8-10 sections.

Slide Review: Thick skin and sun damaged skin

Thick and/or sun damaged skin will appear as a translucent layer of cells outside the epidermis. This section shows scabby, sun damaged tissue, so the layer of cells is rough and uneven. In the mid dermis, the grayish/lavender area is most likely actinic elastosis, or the accumulation of abnormal elastic tissue in the dermis, also a result of sun damage.

This next section shows the thick skin found in the palms of the hand or the soles of the feet. Note that even though the image (courtesy of http://www.dartmouth.edu) points out the "thickened layer of squamous cells," it is not referring to SCC. Healthy squamous cells are a normal part of the superficial epidermis. The outermost squamous cells are heavily keratinized, creating a thick layer of dead cells that protects our hands and feet. 

For comparison, here is a section of normal tissue only a thin layer of dead squamous epithelial cells.