While sampling (cut in) does not necessarily require that a specimen be cut, as is often the case with biopsies, this is something which the vast majority of regular surgical pathology laboratories do. This very much artisan processing step when grossing requires appropriate instruments. This post discusses predominately personal experience that reflects specific conditions of local institution/s.
There are two kinds of cutting instruments: those for soft specimens and those for calcified specimens. The choice of the in cutting instruments variants is less than during specimen immobilization. Moreover, some instruments, resembling tomato slicers, combine the tasks of cutting and immobilization. For example, suggested by MOPEC or more sophisticated by MILESTONE (ProCut).
The use of knives has been common for autopsies and large specimens. However the modern requirements for precise margins of resection and staging move the scale of choice towards blades due to their flexibility during section, their sharpness, and their disposability.
Nevertheless, knives will remain popular in the gross room, but they are shorter than old dissection knives, thinner, hopefully sharper made from high quality material.
It is unnecessary to describe all kinds of blades and knives offered by the manufacturers. Here we provide the principle of the choice of an appropriate knife or blade for the surgical pathology laboratory. Different types of disposable scalpels are not popular in surgical pathology (too expensive).
Blades are distinguishable by the standard numbers 10, 15, and 22. Although 10 and 15 can be advantageous for very small biopsy specimens – such as ophthalmology surgery – the standard is 22 as it fits the standard handle. Handles used to be wooden, although are now made of plastic. While different kinds of metallic handles may look attractive, they are too thin. This is especially evident when needing to change blades, something which should be done often. In terms of the ideal handle, in my experience, it is pear-shaped handle that reliably fits the palm.
Blade changing is an issue deserving special attention because of safety considerations. In my opinion, while the devices for removal (Mopec’s, for instance) may look attractive, they are a waste because they are not reliable. They do not work with every type of handle, and the blade or handle can sometimes become stuck in the device.
I do not have an experience with BLADEX, Inc. Safety Blade Exchanger. On the companies video, the handle is different than most used in the USA blade handles.
The safe way to remove the blade is by lifting the part that adheres to the handle with forceps, or even by thumb. This easily removes the blade. Really, I do not think that the safety blade exchangers are necessary. Such devices take precious space on the grossing table, but the blade is changed so often that additional device cannot substitute for attentive skilled work.
Different kinds of blades starting with Double sided Grossing Blades and finishing with a regular Gillette like razor have limited used. First are cumbersome, proprietary, although some like them. The Gillette like razor blade is difficult to manage, brittle, in general unsafe. With some developed skills, it can be used in after ophthalmology surgery.
A grossing knife with two parallel blades intended to provide uniform thickness of the sample. However, this device is useful in autopsies sampling, but for every day work in surgical pathology with constant change of the processing mode and the type of specimen, this kind of knife is cumbersome.
Instruments for calcified specimens
There is a variety of instruments and a difference in opinions regarding them. The main perhaps question is in the attitude toward hand or mechanical sawing. I prefer hand sawing, using mechanical sawing in simple bone specimens. Bur even in a case of a femoral head with degenerative arthritis hand sawing is more manageable and more open to diagnostic revelations.
The variety of cutting instruments is presented in our book Grossing Bones: Principles, Techniques, and Instruments (2017, Amazon.com).