Monday, 18 October 2010

T 266/07 – Using The New Blinkers

The present decision is interesting because it puts into practice the teaching of G 1/07:

Independent claim 1 of the sole request reads as follows:
“Method for producing a magnetic resonance angiogram of selected vasculature in a subject, wherein a contrast agent has previously been introduced into the selected vasculature so that the intensity of the NMR signal of the vasculature dominates the intensity of NMR signals in other materials within an entire field of view, comprising the steps:
a) operating the MRI system to perform a pulse sequence which includes:
i) producing an RF excitation pulse to excite spins in the entire field of view which includes the selected vasculature;
ii) applying a phase encoding gradient along a first axis;
iii) applying a radial gradient directed at an angle θ in a plane perpendicular to the first axis; and
iv) acquiring an NMR signal during the application of the radial gradient to sample an angular projection of the data in k-space having NR data points radially spaced along a projection;
b) repeating step a) with a set of different phase encoding gradient values for each of a plurality of different radial gradient angles θ until k-space is sampled, wherein the plurality of different radial gradient angles θ is less than NR π/4 in number so that a sparsely sampled three-dimensional k-space data set is acquired;
c) Fourier reconstructing along the first axis a three-dimensional volume image of the entire field of view from the sparsely sampled k-space data set, whereby the spacial resolution of the resulting image is not affected by the sparse angular sampling and the artifacts associated with the sparse angular sampling are acceptable being no more than a few percent of the signal associated with the tissue surrounding the vasculature,
d) providing reduction of image artifacts generated by the sparse sampling by subtracting from the image reconstructed in step c), a mask image of the selected vasculature that was acquired before the contrast agent was introduced into the selected vasculature; and
e) displaying the reconstructed image produced in step d).
The Examining Division (ED) refused the application because it implicitly comprised a surgical step.

[4.1] In paragraph 1 of the reasons for the contested decision, the ED found that the claimed method of producing a magnetic resonance angiogram (MRA) implicitly included the invasive step of introducing – by injection – a contrast agent into the vasculature of a patient to be examined, and refused the claims under A 52(4) EPC 1973 on the grounds that the method had a surgical character. The Board does not agree with this finding.

[4.2] It is noted that since the contested decision was issued, the Enlarged Board of Appeal has handed down decision G 1/07, in view of which the objection under A 52(4) EPC 1973 raised in is no longer valid.

In particular, G 1/07 [4.3.2] holds that
“Methods which are merely directed to the operating of a device without themselves providing any functional interaction with the effects produced by the device on the body are teachings in which the performance of a physical activity or action that constitutes a method step for treatment of a human or animal body by surgery or therapy is not required in order for the teaching of the claimed invention to be complete. Hence, even if in such a case the use of the device itself requires the application of a surgical step to the body or is for therapeutic treatment the same does not apply to the claimed method for operating the device.”
[4.3] In the present case, the claimed method is directed to the operating of a magnetic resonance imaging (MRI) system. Whilst the presence of a contrast agent is indeed obligatory for the imaging method defined in claim 1, the method for operating the MRI device is not functionally related to the actual administration of the contrast agent. Claim 1 must be interpreted as only covering the production of an MRA of a vasculature into which a contrast agent has already been introduced. Thus, the actual step of introducing the contrast agent into the vasculature is not included within the scope of the method claim.

[4.4] When this interpretation is invoked the method according to claim 1 represents a technical method for producing an MRA of a selected vasculature by means of a magnetic resonance imaging system, and not a surgical method. Claim 1 is therefore not concerned with a method of surgical treatment of the human or animal body within the meaning of A 53(c) and is, therefore, not excluded from patentability under this provision.

Should you wish to download the whole decision, just click here.

Should you want to re-read relevant passages of G1/07, you can do so here.