T 0467/20 - Moved through the vessel of the patient

Key points

•  Claim 1 is directed to a system comprising "a first instrument sized [e.g. a catheter] and shaped for introduction into the [blood] vessel of the patient", a similar second instrument, and a computing device configured to "obtain pressure measurements from the first and second instruments while the second instrument is moved longitudinally through the vessel of the patient"
• The Board: "The contested patent relates to a system for assessing the severity of a stenosis in a blood vessel."
• The Board finds the claim to be sufficiently disclosed and inventive.
• Of note, Art. 53(c) is not discussed. Hence, a computer configured to perform calculations on output from a device that by way of surgery is introduced into the body of a patient is not excluded. 
• This decision appears in line with established case law, see e.g. T 2136/19. For a different approach, see T 0944/15.
• The present decision also illustrates the difference in the effect of Article 52(2) and Article 53 on inventive step. Features defining subject-matter excluded under Art. 53(c) can very well contribute to inventive step.
• " it is common ground that D1 does not disclose feature 4.3 of claim 1, whereby the computing unit is further configured to "modify the visual depiction of the vessel to simulate one or more treatment options based on expected results of the one or more treatment options on the pressure differential". " 
• This feature pertains to the presentation of information. 
• " The appellant [opponent] formulated the objective technical problem to be solved starting from D1 as being to facilitate the selection of a treatment method." 
• The Board seems to follow this formulation.
• " The Board first notes that D1 itself does not suggest that the "integrated graphical image output" may be used to simulate various treatment options. Without hindsight, the person skilled in the art proceeding from D1 alone would not implement feature 4.3 without an inventive step." 
• The distinguishing feature is the presentation of information. Interestingly, the Board does not comment on the case law that " A feature defining a presentation of information produces a technical effect if it credibly assists the user in performing a technical task by means of a continued and/or guided human-machine interaction process (T 336/14, T 1802/13 and T 1185/13). " (CLBA 10t hed. I.D.9.12.10.b).
• Implicitly, the method of treatment is a technical method and selecting the right treatment method is (apparently) seen as a technical problem, such that "facilitate the selection of a treatment method" is considered to be a technical problem.

EPO 

The link to the decision is provided after the jump, as well as (an extract of) the text of the decision.

https://www.epo.org/law-practice/case-law-appeals/recent/t200467eu1.html

1. Subject-matter of the contested patent

The contested patent relates to a system for assessing the severity of a stenosis in a blood vessel.

As illustrated in Figure 3 of the patent, reproduced below, a stenosis (108) is a blockage or narrowing of a blood vessel (100), caused for example by accumulation of plaque, which decreases the space available for blood to flow and results in a drop in blood pressure across the stenosis.

FORMULA/TABLE/GRAPHIC

The claimed system comprises a first and a second instrument, both sized and shaped for introduction into the vessel, such as a guidewire (130) and a catheter (132) in the example illustrated in Figure 3.

The system further comprises a computing device in communication with both instruments and configured to perform the following steps:

(a) obtain pressure measurements from the first and second instruments while the second instrument is moved longitudinally through the vessel of the patient from a first position to a second position while the first instrument is maintained in a fixed longitudinal position with respect to the vessel.

In the example illustrated in Figure 3, the catheter (132) remains at a fixed location outside the stenosis while the guidewire (130) is moved through the stenosis. Hence pressure can be measured simultaneously both at a fixed reference location outside the stenosis and at various locations across the stenosis.

(b) visually depict the vessel on a display based on a pressure differential calculated as the ratio of the pressure measurements obtained from the first instrument and the pressure measurements obtained from the second instrument.

Examples of such a visual depiction of the vessel based on the calculated pressure differential are shown, for example, in Figure 7 and Figure 9 (dashed curve) reproduced below. By analysing the shape of plots 212 and 236, this visual depiction can be used to both identify the location of a stenosis and assess its severity (paragraphs [0041] and [0046]).

(c) modify the visual depiction of the vessel to simulate one or more treatment options based on expected results of the one or more treatment options on the pressure differential.

An example of a visual depiction of the vessel modified in accordance with step (c) is the solid curve shown in Figure 9, reproduced below, in which a treatment option across the region 244 previously identified as a stenosis has been simulated on plot 238. By simulating and evaluating a plurality of treatment options, the most promising treatment approach for the patient can be selected (paragraphs [0047]-[0048]).

FORMULA/TABLE/GRAPHICFORMULA/TABLE/GRAPHIC

[...]

5. Inventive step

5.1 It is common ground that D1 discloses a system for evaluating a vessel of a patient, especially for identifying and assessing a stenosis (page 1, lines 15-27). Like the system of claim 1, this system comprises (Figure 1) a guiding catheter and a pressure sensor guidewire 5, i.e. a first instrument and a second instrument both sized and shaped for introduction into the vessel. D1 therefore discloses features 1 to 3 of claim 1.

5.2 In use, after the guiding catheter has been positioned proximally to the area to be examined, for example a suspected stenosis, the guidewire is moved past this region of interest. The guiding catheter is then locked in position, and the guidewire is pulled back along the vessel while acquiring pressure data across the stenosis (page 8, lines 7-30). The pressure data is received at a computing unit in communication with the guidewire (processing means 1), processed and combined with image data representative of the vessel (for example an angiogram image) to generate an "integrated graphical image output", i.e. a visual depiction of the target vessel in which the pressure data is mapped onto a corresponding position on an image of the vessel (page 3, lines 20-25; page 2, lines 29-30).

While the processed data displayed in the "integrated graphical image output" may be a "numerical relation" between the pressure data acquired by the guidewire and a static reference pressure obtained initially proximally to the stenosis (page 3, lines 29-30; page 5, lines 11-13), D1 further discloses on page 4, lines 5-6 and claim 9 that "Fractional Flow Reserve (FFR) values may also be calculated and displayed along the vessel". The appellant argued that the resulting "integrated graphical image output" displaying the FFR values along the vessel constituted a visual depiction of the vessel based on a pressure differential (calculated according to feature 4.2), which the respondent contested.

5.3 Regardless of this point of dispute, it is common ground that D1 does not disclose feature 4.3 of claim 1, whereby the computing unit is further configured to "modify the visual depiction of the vessel to simulate one or more treatment options based on expected results of the one or more treatment options on the pressure differential". The Board disagrees that the person skilled in the art starting from D1 would implement feature 4.3 and thus arrive at the subject-matter of claim 1 in an obvious manner, even considering D2.

5.3.1 The appellant formulated the objective technical problem to be solved starting from D1 as being to facilitate the selection of a treatment method.

5.3.2 The Board first notes that D1 itself does not suggest that the "integrated graphical image output" may be used to simulate various treatment options. Without hindsight, the person skilled in the art proceeding from D1 alone would not implement feature 4.3 without an inventive step.

5.3.3 Concerning D2, it is true that this document discloses a system for evaluating a vessel that specifically addresses the technical problem above (paragraph [0013]). To this end, the system of E2 generates various displays to enable a user to simulate the placement of a stent in the vessel and to investigate the resulting effects on the vessel flow properties. On that basis, various treatment options can be simulated to determine the most appropriate one.

5.3.4 However, as submitted by the respondent, the system of D2 is entirely based on OCT measurements, i.e. on an imaging technique on the basis of which not only the morphology of the vessel but also its flow properties are determined and simulated by running a computational fluid dynamics program (paragraphs [0015] and [0121]). Without hindsight, the person skilled in the art would find no incentive in D2 to implement feature 4.3 in the system of D1, in which the vessel flow properties are determined based on pressure measurements and then overlaid on a morphological view of the vessel.

5.3.5 The lumen profiles presented in Figure 25, to which the appellant referred, illustrate the morphology of a vessel, both in an unstented configuration and with various simulated stents implanted. A similar lumen profile for another vessel is shown in the upper part of Figure 23. As such, these profiles obtained from OCT measurements (paragraph [0125]) represent visual depictions of the vessel: however, they are merely based on imaging the vessel and not on its flow properties. Moreover, to simulate the presence of a stent the profiles are only modified based on the stent geometry, namely to reflect how the stent would modify the vessel lumen, and not based on the effects that the stent would have on the vessel flow properties.

Therefore this teaching would not motivate the person skilled in the art starting from D1 to modify the "integrated graphical image output" of D1 to simulate one or more treatment options "based on expected results of the one or more treatment options on the pressure differential", i.e. to implement feature 4.3.

The indication of a VRR value on these profiles, or equivalently the indication of an FFR value as disclosed in paragraphs [0107]-[0110], does not contradict this conclusion. Both parameters VRR and FFR are also calculated from the OCT measurements and characterise the flow properties of the vessel as a whole. Even bearing such an indication, the lumen profiles of Figures 23 and 25 are thus not a visual depiction of the vessels based on these flow parameters. The teaching in D2 that these values are updated as the stent characteristics are changed by a user (paragraph [0121]) therefore does not point the person skilled in the art towards feature 4.3 either.

5.3.6 The appellant also referred to the lower graph of Figure 23. This graph does show two curves representing the total pressure along the vessel as a function of the distance, for the vessel either unstented or stented.

Even if these curves are regarded as visual depictions of the vessel as argued by the appellant, they are also derived from the OCT measurements and are actually a sub-product of the calculation of VRR (paragraph [0121]); moreover, they show the total pressure and not a pressure differential calculated according to feature 4.2. Thus they cannot point the person skilled in the art towards implementing feature 4.3 in the system of D1 either.

5.3.7 Rather, if the person skilled in the art were to combine D2 with D1 to solve the technical problem above, they would simply adopt the optimisation technique disclosed in D2 as a whole. As this technique is based solely on OCT imaging without necessitating pressure measurements, there would in this case be no reason to implement feature 4.3 in the resulting system. The person skilled in the art would therefore not arrive at the subject-matter of claim 1.

5.4 At least for these reasons, the Board concludes that the subject-matter of claim 1 involves an inventive step starting from D1. Due to this conclusion, there is no need to determine whether D1 discloses features 4 to 4.2.

6. It follows from the above considerations that none of the appellant's objections admitted into the appeal proceedings prejudices maintenance of the patent as granted.

Order

For these reasons it is decided that:

The appeal is dismissed.