T 1764/14 06-03-2019

1. The appeal is admissible.

2. The invention

The invention relates to an X-ray diagnostic apparatus for positioning an X-ray generating unit and an X-ray detecting unit around a patient lying on a catheterization table, for example as shown in figure 2 of the application, reproduced below.

FORMULA/TABLE/GRAPHIC

The X-ray units (1, 2) are held on opposite ends of a C-arm (51) and are rotatable around the same imaging axis (SA). The C-arm is held by an arm holder (52) and can rotate with respect to the arm holder around a substantially horizontal axis (Z4). The arm holder is mounted on a stand (53) and can rotate with respect to the stand around a further substantially horizontal axis (Z3), perpendicular to Z4. SA can assume various directions but always passes through the point of intersection of Z3 and Z4, the isocenter (IS). The stand is mounted on a floor rotating arm (54) and can rotate around a substantially vertical axis (Z2) with respect to the floor rotating arm. The floor rotating arm can rotate around a further substantially vertical axis (Z1, coinciding with SA in the figure) with respect to the floor. The catheterization table (18) has a table top (17) with a central line (nearly coinciding with BL) intersecting Z1.

The X-ray diagnostic apparatus further comprises a control unit for controlling the rotation of the floor rotating arm around its axis Z1 and the rotation of the stand around its axis Z2 to bring the C-arm into a position in which axes Z1 and SA coincide. In that position, a first and a second posture lines, respectively connecting axes Z1 and SA with axis Z2, incline at a predetermined angle with respect to the central line of the table top. Figures 5B, 5C and 6A, reproduced below, illustrate configurations of the apparatus satisfying this condition.

FORMULA/TABLE/GRAPHIC

FORMULA/TABLE/GRAPHIC

FORMULA/TABLE/GRAPHIC

According to the application (paragraph [0011] of the published version), especially this last feature makes it possible to easily free working space around particular regions of the patient.

3. Main request

The subject-matter of claim 1 of the main request lacks novelty over D2.

D2 relates to an X-ray apparatus which permits isocentric scanning of a patient at multiple angles of incidence (column 1, lines 7 to 10). With reference to figures 1 and 4, reproduced below, the apparatus comprises a floor rotating arm (24), a stand (25), an arm holder (14), a C-arm (13), an X-ray generating unit (11) comprising a collimator (column 5, lines 20 to 24 and 59 to 61), an X-ray detecting unit (12), and a catheterization table (15) as defined in claim 1.

FORMULA/TABLE/GRAPHIC FORMULA/TABLE/GRAPHIC

The axes of relative rotation of these elements correspond to the claimed ones according to the following scheme:

Z1=AXIS 3

Z2=AXIS 4

Z3=AXIS 2

Z4=AXIS 1

SA=AXIS RX

The appellant argued that D2 did not disclose a floor rotating arm as claimed. However, element 24 in figure 4 is such a floor rotating arm since it has one end mounted on a floor surface and rotatable around vertical axis 3, and an opposite end supporting stand 25 (column 5, line 61 to column 6, line 4).

The presence of a control unit, disputed by the appellant, is implicit for apparatuses of the kind disclosed in D2 in view of the disclosed possibility of obtaining "a scan of the isocenter over a patient's entire body without having to displace the examination table" (column 5, lines 48 to 52) by a combined rotation around two axes. It is technically unreasonable that such a combined rotation should be performed manually. Moreover, column 2, lines 62 to 64, mentions a movement taking place "under the control of the operator", which equally presupposes the presence of a control unit.

The appellant further argued that D2 did not disclose that each of the possible rotations about the respective axes could be independently controlled. The Board does not share this view. First of all, the presence of those distinct axes of rotation alone makes it technically reasonable to associate them with distinct degrees of freedom of the X-ray apparatus, which implies an independent control of each possible rotation. Moreover, the description in D2 of all the possible movements which can be obtained by angular movements about AXES 1, 2, 3 and 4 (column 3, line 22 to column 4, line 62) presupposes that each of the possible rotations about the respective axis can be independently controlled. In this context, the particular movement to obtain a scan of the whole body of a patient lying on the examination table by a combined rotation around two axes (column 5, lines 44 to 52), referred to by the appellant, is only one of the possible movements obtainable with the apparatus of D2.

Since the claimed configuration with the C-arm located immediately above the floor rotating arm (AXIS RX coinciding with AXIS 3) is shown in figure 1, and AXES 3 and 4 can rotate (independently from each other) in a broad angle range (column 3, lines 55 to 58) to permit freedom of access to the patient's head (column 5, lines 52 to 55), the apparatus of D2 can be controlled to reach, in the defined interlocked state, the predetermined position defined by reference to a predetermined angle of the posture lines with respect to the central line of the table top, according to claim 1. The mere possibility of such a control implies the possibility of instructing the apparatus accordingly, i.e. by means of a "specific user instruction" as defined in the claim.

Hence, D2 anticipates all the features of claim 1 of the main request.

The appellant argued on the basis of a "specific (single) user instruction" allegedly requiring that the claimed configuration be reached by rotating the C-arm "at a single move". However, the claim merely requires that the control be performed in accordance with a specific user instruction. There is no definition of how the specific user instruction is imparted. Hence, the appellant's references to a "single move" and a "single instruction" is of no relevance.

It follows that the main request cannot be allowed since, contrary to the requirements of Article 52(1) EPC, the subject-matter of claim 1 is not patentable for lack of novelty over D2 (Article 54(1) and (2) EPC).

4. Auxiliary request I

Claim 1 of auxiliary request I further requires that the specific user instruction is based on an operation of a button and causes the C-arm to "automatically and quickly" reach the posture in which the C-arm is located immediately above the floor rotating arm, and that the predetermined angle of the posture lines with respect to the central line of the table top is "finely adjustable by manually operating a button".

The Board agrees with the appellant that D2 does not disclose that instructions can be imparted by operating buttons.

As regards the suitability of the control unit of D2 for automatically and quickly moving the C-arm and for finely adjusting the predetermined angle, the Board considers that this suitability is inherent to D2, in particular since "quickly" and "finely" are relative and unprecise terms.

The Board further notes that the claim does not define an approach position or an approach position button. The claim does not specify either that two distinct and sequential instructions, for first moving the C-arm of the apparatus to a predetermined posture and then adjusting a predetermined angle, are imparted. In this respect, the fact that the two functional features of the control unit (i.e. its suitability for "automatically and quickly" moving the C-arm to the predetermined position defined by reference to a predetermined angle of the posture lines with respect to the central line of the table top, and for enabling a fine adjustment of that predetermined angle) are defined one after the other, does not imply that the fulfilment of the two functional features depends on sequential instructions. Contrary to the appellant's arguments, there is not even a definition of a time scale or sequence in claim 1 of auxiliary request I, in particular since it is a device claim. The term "finely", referred to by the appellant, has nothing to do with a time scale or sequence, as it qualifies how the predetermined angle can be adjusted.

In view of the above, the defined possibility of imparting instructions by operating buttons is in no direct relation to the effect, mentioned by the appellant, of quickly and safely moving the X-ray apparatus away from the patient. Rather, it has to be seen as addressing the problem of imparting specific user instructions for moving the C-arm to the predetermined position defined by reference to a predetermined, yet adjustable, angle of the posture lines with respect to the central line of the table top.

D2 is silent on how user instructions for moving the X-ray apparatus are to be imparted. The skilled person, desiring to devise an input interface for the apparatus of D2, would have to choose one of a number of equivalent, known technical means. For example, providing a touch screen with a virtual button (virtual buttons are also contemplated in the present application - figure 4 and paragraph [0028] of the published version) for setting angles of rotation around a certain axis, and with a further button for imparting the order of performing the set movement, would be one of several equally obvious possibilities. The fact that such a touch screen is per se known, put forward by the Board during the oral proceedings, was not disputed by the appellant.

It follows that the skilled person would arrive at the subject-matter of claim 1 of auxiliary request I in an obvious way.

Hence, auxiliary request I cannot be allowed since, contrary to the requirements of Article 52(1) EPC, the subject-matter of claim 1 is not patentable for lack of inventive step (Article 56 EPC).

5. Auxiliary request II

Compared with claim 1 of auxiliary request I, claim 1 of auxiliary request II merely adds the suitability of the control unit for controlling rotation of the floor rotating arm after controlling the rotation of the stand. This suitability depends on a specific user instruction only qualified by the fact that it can be imparted by operating buttons. In particular, the claim does not specify that distinct and sequential instructions are imparted.

The suitability of the control unit of D2 for controlling rotation of the floor rotating arm after controlling the rotation of the stand in accordance with a specific user instruction is given, since each of the possible rotations about the respective axes can be independently controlled, as explained above.

It follows that the subject-matter of claim 1 of auxiliary request II is not inventive for the same reasons as those provided in relation to auxiliary request I.

Hence, auxiliary request II cannot be allowed since, contrary to the requirements of Article 52(1) EPC, the subject-matter of claim 1 is not patentable for lack of inventive step (Article 56 EPC).

6. Auxiliary request III

Compared with claim 1 of auxiliary request II, claim 1 of auxiliary request III essentially adds the suitability of the control unit for correcting a direction of an image in accordance with rotation of the X-ray detecting unit or the collimator after controlling the rotation of the stand. This suitability, which amounts to the suitability for performing a certain rotation about the imaging axis, depends on a specific user instruction only qualified by the fact that it can be imparted by operating buttons. In particular, the claim does not specify that distinct and sequential instructions are imparted. The further amendment of the claim, reciting that the control unit "performs to control rotation" instead of "controls rotation" does not introduce any further limitation of the subject-matter claimed. The appellant did not argue otherwise.

The suitability of the control unit of D2 for performing any rotation about the imaging axis after controlling the rotation of the stand in accordance with a specific user instruction is given, since each of the possible rotations about the respective axes can be independently controlled, as explained above.

It follows that the subject-matter of claim 1 of auxiliary request III is not inventive for the same reasons as those provided in relation to auxiliary request I.

Hence, auxiliary request III cannot be allowed since, contrary to the requirements of Article 52(1) EPC, the subject-matter of claim 1 is not patentable for lack of inventive step (Article 56 EPC).

7. Since none of the appellant's requests can be allowed, the appeal must be dismissed.