Davidson’s Marking System accompanied my life at the grossing table for many years. I used the wooden holding trays not only for inking but as immobilization gadget (“Equipment, Instrument & Gadgets” link).
Dr. Terence Davidson’s initial proposal of using marking system for Mohs surgery now extends far beyond this purpose. Multicolor inking is obligatory in many cases of tumor surgery to meet the diagnostic staging requirements.
The specimen inking becomes more and more the standard practice in grossing biopsies. Biopsy inking, except large breast excisional biopsies, is different from general inking of surgical pathology specimens. The main purpose of inking is specimen orientation, predominately during embedding, although in some occasions inking also helps to define the margin of excision. These circumstances determine some particularities of inking in every day surgical pathology practice.
Te original design of the Davidson’s Marking System holding tray is bulky for biopsies. Five colors are superfluous for biopsies. The new 3-dye Wood Holding tray is in principle the same as the original holding tray. However three dyes do not solve the problem of inking the skin biopsy with the request for examination of margins because usually two or four colors are used depending on the orientation by the surgeon (a suture or a different mark).
Bradley Products, Inc. continues to develop some applications to the Davidson’s Marking System. Now plastic holding trays are available. However they are variations of the initial design. Pegs designed to hold the cups are not used in practice although they have some rationality in the intention.
The enormous amount of biopsies in modern surgical pathology laboratory determines different ways of the grossing table’s set up. The Figure 1 presents the working tray for biopsies processing on a standard grossing table. You can see how overcrowded it is. If we have a multicolor specimen, we need to change the set up. Under conditions of assembly line biopsies processing in surgical pathology laboratory, it is a waste of time that slows down productivity. The tray is begging for a portable inking gadget.
Figure 1. A tray for biopsies processing
Biopsies inking has some particularities. Here are some of them:
1. Inking is predominately monocolor with maximum four colors.
2. The color of the ink should be bright to contrast with white-grey paraffin wax during embedding.
3. The ink application should be precise as mush as possible.
4. The mordant use is obligatory, but very precise and limited.
The standard Davidson’s Marking System holding tray or its recent modifications do not meet these requirements. Design of gadgets for biopsies ought to be different from general surgical pathology equipment which is oriented predominately on large and small specimens.
Figure 2 presents the modification of the standard holding tray.
Fig. 2 Modification of Davidson’s Marking System holding tray
Summarization of the rational design of holding device gadget for biopsies inking in surgical pathology laboratory:
a/ portable on the grossing table crowded for an assembly line fast grossing processing;
b/ easily manageable for different operations;
c/ cleanable to keep neat and prevent specimen’s contamination.
The website proposes a modification of the Davidson’s Marking System holding tray. It is reasonable to have a special biopsy inking kit.
A curved plastic or wooden platform (4 cm in width x 18 cm in length x 4 cm in high) as a tray for holding four small containers (2 cm in diameter) for four colors ink. The standard biopsy does not require more than 4 dyes, for example skin excision biopsy with a suture marking that determines orientation of the margins of excision. The most biopsies a monocolor or two color inking.
Holes for holding dye applicators and for containers for mordant (3 cm in diameter) with foam pads as applicators for mordant are from both ends of the platform. Mordant and pads are kept in different containers. The working pads can be kept in the mordant to be soaked for immediate use.
Below is the general plan of the platform’s design.
Diagram of the general design of the platform for biopsies inking.
The containers for the dyes should have wide openings for convenience of operation.
The lids should have hinges to easily be closed, especially for mordant to prevent evaporation (Fig. 3).
There can be attached a round tab like space to keep a plastic corresponding color applicator (Fig. 4).
The best dye applicator looks as a plastic StrataTip® Sample (Fig. 4). It is or was used in molecular biology laboratories (Stratagene is the manufacturer), but this is only an example of different kind of applicators and sometimes a mordant as well.
Fig. 4. Plastic applicators
The container for mordant should be more voluminous than dye containers and it should have a lid similar to dye containers to keep it closed as much as possible.
The foam pads container for mordant application should be rectangular to follow the most popular blue pads size (Fig.5).
Fig. 5. The container for mordant foam applicators
In opposite to containers with dyes and mordant, the lid should not be close tightly.
This design has advantages:
One stop shop gadgets that combines all necessary tools
New look. Curved form saves the grossing table’s space. This economy is important for overcrowded grossing table.
It is easier to add from the stock bottle small quantities of dyes.
This gadget proposal is posted for everyone who wants to use it in laboratory practice or able to commercialize it in a product for the sake of improvement biopsy grossing technology.