Sampling Immobilization in Surgical Pathology

Immobilization during sampling is underestimated in grossing  (cut in) in the surgical pathology laboratory. There is no question that surgical pathology gross section requires a firm surface beneath the specimen. Though for different reasons, the firmness of the specimen determines the need for immobilization. In the vast majority of cases, it is not a problem for a skilled grossing person to make reasonably satisfactory sections. However, some specimens require certain skills supported by special techniques, devices, gadgets, and improvised at-hand materials.

Nobody is cutting in the air. It is impossible to cut on a pillow. The object of the cutting needs immobilization. Specimen sampling immobilization has three main aspects: cutting surface, holding instrument (including a hand), immobilization devise.

The importance of the cutting surface is often underestimated in grossing practice. The cork boards disappeared from practice for good. Filthy, with uneven surface, they are appropriate now for stretching a specimen in preparation for even fixation. However, they had a rational idea of additional immobilization of the specimen while cutting due to friction between the surface the outer layer of the specimen to be cut. In this regard, the modern grossing board with their smooth surface, more or less acceptable for large specimens due to their cleaning convenience, are not appropriate for biopsy and small specimen cutting because the surface should “grasp” for immobilization during cutting.

For a long time, I’m propagating the well know rubber surface of the cutting board. Rubber provides the necessary resistance to the cutting instrument, friction, and relative “softness” of the surface.  A cafeteria tray can be an improvised example of such a board.

 

easy to clean

easy to clean

Tray cutting board

As an equivalent of the rubber surface, a Styrofoam material can be useful as a cutting surface. Because Styrofoam board re unpractical for many reason, the insert of a standard prefilled formalin container’s lid, can be an excellent “individual for every specimen cutting board.”

skin section ready

It seems that in the future manufacturer will provide the surgical pathology laboratory with gelled cut resistant surface grossing boards, like the handle of hair brush, but it will not occur tomorrow.

In the foreseeable future, nothing can substitute as a holding instrument a forceps. The industry offers a great variety of them that is justified due to different kinds of specimens and personal preferences. Among them, three types of forceps can be distinguished for practical purpose: 1. thin branch forceps; 2. Regular serrated forceps; 3. Russian holding forceps

Thin branch forceps are used for different purposes in sampling biopsies. They are indispensible in sampling specimens with two open areas as in a cervical cone biopsy

LEEP

Cervical cone initial ink

or  during triage kidney biopsies as a part of a kit.

Renal needle biopsy triadge kit

Renal needle biopsy triadge kit

 

Russian holding forceps is indispensible for situation that require strong forth in specimen holding for immobilization, for instance in bone or other calcified specimen cutting of sewing.

 

Russian Tissue Forceps 10" fits the notch

Russian Tissue Forceps 10″ fits the notch

Russian Tissue Forceps (10" and 6")

Russian Tissue Forceps (10″ and 6″)

 

Femoral head fracture

Although a paddle forceps is useful for cutting fatty tissues or sometimes thin specimens, it is especially useful for fragile large nodulated polyps. The grip of a 15 cm length with a 2.1 cm x 2.1 cm pad makes the cut easier to keep together otherwise falling apart fragments.

slide show 5

 

Immobilization devices are critical for successful sampling, especially in a case of calcified specimens. This is the reason that most of devices, contrivances, and gadgets are designated for bone cutting.

A decent section of a femoral head with osteoarthritis can easy be made whether using a mechanical or hand saw. Technical difficulties arise when sampling calcified tumors, fragile complicated bones, small fragments of bone, and with serial sections. In my experience, a hacksaw is preferable for these specimens. There are certain particularities in sawing technique, but the main issue is preventing the specimen’s movement due to a “snag” between the saw and the calcified tissue. The employment of the “third hand” principle for additional immobilization makes a significant difference.

It is important to find an appropriate vertical surface to press the bone specimen against during sawing. Depending on the size of the specimen, the vertical surface can be different in form, but must be more or less flat. A Davidson’s Marking System stand is optimal as an immobilization support gadget. This wooden stand with round bottle holders and multiple, different shaped notches can adjust to accommodate many configurations of bone specimens. The pegs are very useful, especially if many of them are flatted to be the “third hand” during sectioning

Third hand

In the case of a fragile bone or calcified tumor, it is reasonable to use a hard-pressed packing carton as an immobilization support at-hand material. In this situation, the wall, as the “third hand”, prevents the fragile bone’s surface from crashing, but the cutting instruments (saw for example) pass through the carton, maintaining the integrity of the specimen and the section.

 

The base of the fragile bones of theampytated nose  are pressed against the border of the hard-pressed carton tray

The base of the fragile bones of theampytated nose are pressed against the border of the hard-pressed carton tray

The specimen is pressed against the border

The specimen is pressed against the border

 

The success of Exact Saw is not in the cutting blade, which presents in most of the mechanical saw (MarMed for example), but is a metallic vertical board. This detail of the design is demonstrated only on the you Tube video, but this is the crucial part that made exact bone cut possible.

A different form of firm but relatively soft immobilization is a vacuum base vice.

maxillavisebubble

 

MaxillaMask 8-19-04 016

MOPEC’s Saw stand can be a useful immobilization device if combined with hard-pressed carton. The latter allow the saw go through but preventing the object, bone for instance from cracking during the final saw movements.

hard-pressed carton on the Mopec's stand

 

Hard -pressed carton on Mopec's saw stand

Hard-pressed packing carton, as immobilization gadgets, is my passion. It provides stability, flexibility, and reliability during sawing complicated bone specimens.

Larynx hardpressed

See special article.

A wood clamp can be used is some occasions if the bone specimen is large and there is no any other method for immobilization.

DCF 1.0

DCF 1.0

Simple stands like MOPEC’s for amputated leg

MopecAbovetheKneeSpecimen2_large

Dr.Peters offered a special immobilization device close to a vise by idea.

Peter's vise1

Or a bucket with water can be used for large specimens. I like the bucket more not only as my suggestion, but it is more reliable for immobilization.

 

led supportbacket

The uniformity of biopsy gross section has always been the goal, but it has now become a necessity in microwave accelerated processing technology because the protocol depends on the size of the sample. While implementing the Sakura Finetek Xpress® (Torrance, CA) microwave processing instrument, the University of Miami/Jackson Memorial Hospital developed a grossing board with a slotted metal plate and a track for knife/blade section. Sliding the knife/blade in the track along the surface of the cutting board produces uniform (1.5 mm) thickness sections. Sakura Finetek Accu-Edge® Grossing Tools include specially designed grossing board to accommodate different size specimens by using “adjustable wells that ensure to an exact thickness”, as is stated in the company’s promotional literature.  Actually, the bottom of the well serves as a “third hand” of sorts in the biopsy immobilization for uniform section.

A completely different technological approach presents the Biopsy Uniform Section device which implements the principle of “third hand” immobilization. The core of the design is its three features: a specific (2 mm, 3 mm, and 4 mm) horizontal sidebar for a chosen thickness of the section, a vertical sideboard, and a V- notched slot for the cutting blade. The sideboard provides immobilization for the end of tissue to be cut functioning as the “third hand.”

BUSMilestonePrototype

 

 

 

 

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