Authors: Mark Steven Whiteley, Sienna Esme Davey, Gabriel Mark Placzek
Categories: Original Article, Access and invasiveness classification, keyhole, minimal access, minimally invasive, non-invasive
Source: Journal of Minimal Access Surgery
The rapid development of less invasive and traumatic medical procedures has resulted in a mixture of terms used to describe them, without any agreed definition for each. This is confusing to both medical professionals and patients and can lead to unrealistic patient expectations. The aim of this article is to show the current confused nomenclature and to suggest a new, simple classification based on access and invasiveness (AI) that can be applied to any medical procedure.
We performed an online search for definitions for ‘non-invasive’, ‘non-surgical’, ‘minimally invasive’, ‘minimal access’, ‘pinhole’ and ‘keyhole’. We then searched peer-reviewed medical papers (PRMPs) and patient facing websites (PFWs) for the following index procedures, to see which of the original 6 terms were used to describe transvaginal ultrasound, sclerotherapy for leg veins, botulinum toxin injections, dermal fillers, endovenous thermal ablation and laparoscopic gall bladder removal.
We found a wide variety of definitions for each of the initial terms. In both PRMPs and PFWs, there were a variety of terms used for each index procedure (i.e.: transvaginal ultrasound, injections of sclerotherapy, botulinum toxin or dermal fillers being both ‘non-invasive’ and ‘minimally invasive’) showing confusion in the classification of procedures. We suggested the ‘AI classification’ based on access (A - none, B - natural orifice or C - penetrating an epithelial surface) and invasiveness (1 - none, 2 - surface damage, 3 - needle = <21G, 4 - cannula >21G but not a surgical trocar, 5 - surgical trocars or small incisions and 6 - incisions).
The current confusion of terms used for procedures that are less invasive than the open surgical alternatives leads to confusion and possible false patient expectations. We have proposed an AI classification that can be applied easily to any procedure, giving a uniform classification for medical professionals and patients to understand.
Keywords: Access and invasiveness classification, keyhole, minimal access, minimally invasive, non-invasive
Over the last three decades, there has been a move from open surgery towards more minimally invasive alternatives. However, there are many different terms used for such surgery and procedures such as ‘non-invasive’, ‘non-surgical’, ‘minimal access’, ‘minimally invasive’, ‘keyhole’ and ‘pinhole’. Many of these are used interchangeably and there is no clear definition as to which is which.
The situation is made more confusing with the advent of increased medical content on the Internet, some which aim to be educational, but much is also promotional. This has resulted in the tendency to make the invasiveness of any procedure appear as minimal as possible.
Examples of such descriptions are the injection of sclerotherapy solutions or foam for varicose veins and the injection of botulinum toxin into the facial muscles both being widely described as ‘non-invasive’.[1,2,3,4,5,6,7,8,9,10]
Although it may suit practitioners to call such procedures, ‘non-invasive’, non-medically aware patients may well be dismayed to find that the advertised ‘non-invasive’ treatment entails injections with a hypodermic needle through the skin and into structures beneath.
We decided to review the current definitions for each of these terms, and then search peer-reviewed medical papers (PRMPs) and patient facing websites (PFWs) to identify the extent of the different use of these terms for certain index procedures.
Finally, we present a simple classification that appears to cover all medical procedures. This classification uses two components - (1) Access and (2) invasiveness. Use of this ‘Access and invasiveness (AI) classification’ would allow doctors and practitioners to classify any of their procedures honestly, patients to know the AI of any procedure and regulators to be able to stratify different procedure types and possible risks associated with each approach.
We performed an online search for definitions of each term below, to gauge whether the available definitions for each were clear and uniform or whether there was a discrepancy between the stated definitions. As some of these terms are also used for other areas outside of medicine, we restricted the definitions used to those pertaining to medical
We selected a set of commonly performed procedures that are usually associated with the above definitions. The selected index procedures
For each of the terms defined above, we searched both PRMPs and then PFWs, to see if there was any evidence of confusion as to the classification of each of the index procedures.
Online searches were performed by searching each defined term crossed with each index procedure in turn. PRMPs were searched using PubMed (https://pubmed.ncbi.nlm.nih.gov/) and PFWs were searched using the search engine Google (https://www.google.co.uk/).
We considered the components of any procedure in terms of how a patient might perceive its ‘invasiveness’. There are two main
We decided that we would only consider the AI and not the procedure itself and not the effects or risks of any substance injected or procedure performed once access had been achieved.
We analysed 27 definitions of ‘non-invasive’ on a simple Google search, and we classified them into groups, defining non-invasive:
A search of the index procedures listed in the methods section above, on PubMed
A search of the same procedures on Google
Although the strict definition of this term in the online dictionaries was uniformly simple as either a treatment that does not involve cutting open the body,[59] or ‘not of, relating to, involving or used in surgery,’[60,61] one PFW stated that ‘non-surgical treatments’ are known as ‘non-invasive’ and ‘do not involve the skin being cut or instruments being inserted into the body’ - but then includes ‘injected solutions’ as an example.[62]
A search of PRMPs for non-surgical (no surgery) being used in relation with the index procedures
Searching for the index procedures being called non-surgical (no surgery) on PFWs we
This term is used widely and with a variety of
Searching PRMPs for which of the index procedures were classified ‘minimally invasive’, showed that all these procedures have been published as minimally invasive
A search of the same procedures being called ‘minimally invasive’ on PFWs
The term ‘minimal access’ is usually used interchangeably with ‘minimally invasive’ in terms of medical procedures.[154] Definitions of minimal access that do not reference a minimally invasive approach echo the definitions of ‘minimally invasive’. Thus, ‘minimal access is defined as ‘one or more small incisions instead of a large incision’[155] or ‘reduced trauma of access, which allows more rapid recovery.[156]
A search of the index procedures in PRMPs
A search of these same index procedures on PFWs showed no examples of any of the index procedures being called ‘minimal access’ procedures.
The little there is available for the definition of ‘Pinhole’ when related to surgery is mainly centered around gum disease. A John Chao, D.D.S., claims to have patented the Chao Pinhole^®^ Surgical Technique (PST^®^)[158] which is a treatment for gum recession. Hence, most explanations of pinhole procedures seem to revolve around dental or oral procedures.[159,160] However, we did find one use of ‘pinhole’ as access to blood vessels by interventional radiologists, although it was not presented as a definition.[161]
Our search of the index procedures being described as ‘pinhole’ procedures in PRMPs yielded no results. The same was true for the PFWs search, with the exception of endovenous thermal ablation, which is described as a ‘pinhole’ procedure on a few PFWs.[162,163,164]
The term ‘keyhole’, in relation to surgery, is defined in several
A search of PRMPs papers that call the index procedures ‘keyhole’ revealed the
Searching on PFWs:
New proposed access and invasiveness ‘AI’ classification
We defined the access into the body into three classifications [Table 1]:
We then defined the invasiveness as to a grading of the trauma to the tissue by the access but not by the treatment process.
In the case of ‘hybrid procedures’, where a natural orifice approach is combined with surgical trocars across the skin surface and muscle layers, the approach with the more significant damage to the body should be used for the classification (i.e.: C for the trocars, ignoring B for the natural orifice part of the procedure).
Thus, any procedure or intervention can be defined in terms of the letter and number or the combination of descriptions. Examples of each are outlined in Table 2.
Over the past 20–30 years, there have been tremendous advances in medicine. Some of the most important of these have been the ability to perform effective procedures with far less tissue trauma than previously. Provided the treatments are effective, reduced trauma to the patient’s body usually translates into less pain, fewer complications and a quicker return to normal life.
In most, if not all, medical specialities and procedures are becoming less invasive. However, to remain effective, most therapeutic procedures still need an element of invasiveness as well as tissue trauma, to have the desired effect on the target tissues or organs. Such interventions may well be far less invasive and traumatic than the older operation that they are replacing, but to patients undergoing such procedures, their experience is usually unique and not coloured by having had the previous alternative. As such, although health care professionals can appreciate the great advantages of a new procedure, a patient may still find their individual experience quite traumatic and painful.
Therefore, it is important that patients are given a realistic expectation of the trauma that they can expect from any proposed intervention.
Moreover, in an increasingly commercialised environment, there is a tendency for companies that supply medical equipment or medical services, as well as hospitals, clinics, doctors and nurses, to minimise the expectation of scars, pain, complications or recuperation in their patient-facing information. This is fully understandable, but as a profession, doctors have a moral duty to ensure that such information is accurate and, if challenged, defendable.
For these reasons, and others, such as costing and coding of procedures, research and auditing, it is important for there to be a standardised description as to the invasiveness of each medical procedure.
As we have shown in the results, at the current time, there is no uniform way to define or describe how ‘invasive’ a procedure is. Definitions vary, even for what should be the easiest to define - ‘non-invasive’. Simple English would lead us to expect that ‘non-invasive did indeed mean ‘does not enter or cut the body’. Hence, many patients might be understandably upset to find out that their promised ‘non-invasive’ ultrasound test actually involves the insertion of the probe into their vagina, or their promised ‘non-invasive’ treatment of leg veins or wrinkles involved injections with needles.
Conversely, a patient expecting ‘keyhole’ surgery for varicose veins might well expect a 1 cm incision such as for a laparoscope and be very pleasantly surprised to have only a tiny hole from a Seldinger approach for a 6 FG cannula.
We have proposed a very logical classification that is based on only 2 factors - AI - hence the ‘AI Classification’ [Table 1].
Any, and every, intervention can be defined and classified using this AI classification, as shown by the examples in Table 2. Using the AI classification, patients will know that their laser skin rejuvenation is A1 - non-invasive, but their laser hair removal is A2 - superficial ablation. They will get no surprises when their transvaginal scan is B1 - internal non-invasive, but a colposcopy with cervical ablation is B2 - internal superficial ablation.
Moreover, it gives patients a more realistic expectation if all health care providers explained that sclerotherapy, dermal fillers and botulinum toxin injections were not ‘non-invasive’, but were C3 - penetrating pinhole procedures.
No one likes change and so we expect an initial resistance to this suggestion. However, the use of the AI classification that can be applied to all medical procedures, and that can be understood by patients and health care professionals alike, would help reduce unrealistic patient expectations that might have been caused by the inappropriate use of terms in PRMPs, PFWs or other promotional literature from doctors, clinics or hospitals.
Nil.
There are no conflicts of interest.