SURGICAL GUIDE-WIRE PLACEMENT PLANNING

FIELD OF THE INVENTION

The present invention relates to a medical image-processing device for guide- wire placement planning, a method for guide-wire planning, a medical imaging system, a computer program element, and a computer-readable medium.

BACKGROUND OF THE INVENTION

The detection rate of early-stage breast cancers has improved owing to the application of new scanning technologies. This has caused an increase in the number of surgical procedures performed involving the dissection and removal of tissue containing lesions at an early stage. This has allowed for breast-conserving surgery to be performed with an improved cosmetic outcome.

When performing surgery at this early stage, the lesions are often invisible, and not palpable to a surgeon. Therefore, the surgeon must be guided to the lesion using a guide-wire. The guide-wire is placed by a radiologist before an operation. The radiologist positions the guide-wire so that its tip terminates in an area containing a lesion. A 2D mammogram is used to assist with this process. Techniques for positioning the guide-wire may be improved, though.

WO 2011/145037 describes a system for assisting medical professionals during a breast dissection operation.

WO 2007/135609 describes a system which includes a component that updates a registration between an image space coordinate system and an interventional space coordinate system based on interventional device position information within a patient obtained from intermediate image data indicative of the interventional device location and a position sensor that is located on an interventional device within the patient.

US 2004/0068187 describes a system and method for generating three dimensional (3D) models of bones. It is said that a surgical planner/simulator module may be used to assist a surgeon in making a detailed surgical plan by utilizing accurate 3D bone models and realistic 3D computer graphics and animation. SUMMARY OF THE INVENTION

It would be advantageous to have an improved system for assisting with the placement of guide-wires. To address this concern, a first aspect of the invention provides a medical image-processing device for guide-wire placement planning comprising: an input unit, a processing unit, and an output unit.

The input unit is configured to provide the processing unit with three- dimensional object image data of a region of interest of an object, to provide a location of a target region inside the region of interest of the three-dimensional object image, and to provide a set of generic surgical model information, wherein each generic surgical model represents a surgical protocol.

The processing unit is configured to select a generic surgical model from the set of generic surgical model information, to align the three-dimensional object image data, the location of the target region, and the selected generic surgical model using an image registration process to create a patient-customized surgical model, and to generate at least one guide-wire insertion path in the patient-customized surgical model.

The output unit is configured to display the at least one guide-wire insertion path suitable for insertion of a guide-wire into the object.

Advantageously, this allows an improvement in the exchange of information between the breast surgeon and a radiologist. The correct positioning of a guide-wire is of some importance to the success of an eventual surgical intervention, because a guide-wire can obstruct a surgical tool (like a scalpel) during surgery.

With such an improved exchange of information between the surgeon and the radiologist afforded by the invention, the guide-wire can be placed by the radiologist so that it guides the surgeon to the lesion, without obstructing the incision pathways to be made by the surgeon to find a lesion, according to the surgeon's surgical plan.

According to an aspect of the invention, there is provided a method of surgical guide-wire placement planning comprising the steps of:

a) providing three-dimensional object image data of a region of interest of an object;

b) providing a location of a target region inside the region of interest of the three- dimensional object image;

c) providing a set of generic surgical model information, wherein each generic surgical model represents a surgical protocol; d) selecting a generic surgical model from the set of generic surgical model information;

e) aligning the three-dimensional object image data, the location of the target region, and the selected generic surgical model using an image registration process, to create a patient-customized surgical model;

f) generating at least one guide-wire insertion path in the patient-customized surgical model;

g) displaying the at least one guide-wire insertion path suitable for insertion of a guide-wire into the object.

According to an aspect of the invention, a medical imaging system for guide- wire placement planning is provided. The system comprises:

an image acquisition arrangement,

a medical image-processing device as previously described, and a display unit.

The medical imaging system is configured to acquire image data from the image acquisition arrangement, and to provide the data to the medical image-processing device.

According to an aspect of the invention, a computer program element for controlling a device as previously described is provided.

According to an aspect of the invention, a computer-readable medium having stored the computer program element as previously described is provided.

A surgical guide-wire typically comprises a metal wire which is inserted into a patient's breast, along a pathway, to define an incision route. The tip of the guide wire is typically arranged so that it rests in the center of a lesion. Alternatively, the guide-wire is arranged so that it lies in a sideways relationship with the lesion, so as to "bracket" the lesion. Typically, the guide-wire is applied using a needle. After application of the guide-wire, the needle is removed, and the wire is left in place.

In this description, the term "three-dimensional object image data" refers to a volumetric representation of an area of treatment of a patient, for example a breast.

In this description, the term "target region" is used to define an area inside the three-dimensional object image data which defines the location of a lesion.

In the following description, the term "surgical protocol" is information which represents a sequence of tasks to be carried out by a breast surgeon, in order to perform an excision of cancerous tissue. The surgical protocol can be considered to include qualifiers such as incision points, lengths and angles of incisions, depths of incisions, shapes of incisions. Several surgical protocols may be defined, each representing a different type of breast tissue removal. It will be appreciated that such a protocol may be in a normalized (generic) form, or may, alternatively, be defined in relation to the unique dimensions of a patient.

The term "generic surgical model information" refers to the virtual representation of a generic surgical model, according to a surgical protocol. The generic surgical model may be modelled by a simple volumetric model such as a half-sphere, which denotes the mass of a generic breast. Alternatively, more complex generic surgical models may be provided, such as biomechanical models. The generic surgical model comprises a three-dimensional model, which can be split into three-dimensional segments based on the incisions defined by the surgical protocol.

In this description, the term "patient-customized surgical model" defines the result of aligning a generic surgical model with three-dimensional object image data related to a part of a patient's body, such as patient's breast. This allows a surgical protocol surgical protocol to be demonstrated on a likeness of a patient's breast.

In this description, the term "guide-wire insertion path" means a linear or curved route along which a guide-wire could be inserted into a patient's breast by a radiologist.

The term "treatment object" in this description refers to a human breast, but the invention is also suitable for use in other clinical situations where the accurate positioning of guide-wires before surgical intervention is necessary.

Therefore, it can be seen as a gist of the invention to allow a radiologist to be made aware of a planned surgical procedure, and the implications of the procedure on the placement of the guide-wire. This allows the guide -wire to be placed in a more appropriate way. The proposed approach involves an improvement in the information exchange between a radiologist and the breast surgeon. Initially, the surgeon plans the breast surgery, resulting in a surgical plan. The surgical plan is used by the radiologist for guide-wire placement. In preparation of the guide-wire placement, the surgical plan is illustrated to the radiologist by the guide-wire placement assistant, typically a software package. The guide-wire placement assistant allows planning development and adjustment of the guide-wire placement in accordance with surgical needs. The guide-wire placement assistant also can provide feedback about the guide-wire placement, indicating the discrepancy between the placement and the planned surgical pathway. BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the invention will be described in the following with reference to the following drawings:

Fig. 1 illustrates a method according to an aspect of the invention.

Fig. 2 illustrates a surgical protocol for breast dissection.

Fig. 3 indicates an alternative surgical protocol for breast dissection.

Fig. 4 indicates another surgical protocol for breast dissection.

Fig. 5 schematically illustrates a medical image-processing device according to an aspect of the invention.

Fig. 6 illustrates a surgical and radiology planning environment.

Fig. 7 illustrates a system according to an aspect of the invention.

DETAILED DESCRIPTION OF EMBODIMENTS

At an early stage most cancerous lesions are invisible to the naked eye and consequently not palpable to a surgeon during surgery. To find and excise these invisible cancers, the number of aids are available. The most usual aid is the use of a guide-wire in surgery.

A typical prior-art clinical protocol for the use of guide-wires in breast surgery involves the acquisition of a two-dimensional mammogram using conventional X-ray technology. Whilst the patient is positioned at the X-ray machine, a "check-film" is taken to ensure that the lesion is in an expected position. This task is carried out by the radiologist.

With the patient under local anaesthetic, a needle containing a guide-wire is inserted into the breast to the correct depth so that its tip denotes the cancerous lesion. This is performed with reference to the previous mammogram. Once the guide-wire has been inserted, the surrounding needle is removed. Optionally, one or more further mammograms are taken for the use of the surgeon.

The patient will then be sent to surgery, to have the area of tissue containing a lesion (denoted by the guide-wire tip) removed.

Usually, the excised tissue is sent back to the radiography department, and an X-ray exposure through the excised tissue is made, with the guide-wire still present. This is so that the medical professionals can be sure that all of the cancerous material has been excised.

Problematically, the guide-wire can stray into regions not containing a lesion. The guide-wire can also stray into regions which intersect with incision pathways that the surgeon must make to effect the dissection. This is inconvenient, and can lead to inaccuracy during the operation.

According to an aspect of the invention, a method 10 of surgical guide-wire placement planning comprising the steps of:

a) providing 12 three-dimensional object image data of a region of interest of an object;

b) providing 14 a location of a target region inside the region of interest of the three-dimensional image;

c) providing 16 a set of generic surgical model information, wherein each generic surgical model represents a surgical protocol;

d) selecting 18 a generic surgical model from the set of generic surgical model information;

e) aligning 20 the three-dimensional object image data, the location of the target region, and the selected generic surgical model using an image registration process, to create a patient-customized surgical model;

f) generating 22 at least one guide-wire insertion path in the patient- customized surgical model;

g) displaying 24 the at least one guide-wire insertion path suitable for insertion of a guide-wire of the object.

Therefore, in a method of surgical guide-wire placement planning according to the invention, information exchange between the radiology professional and the surgical professional is enhanced, because information about surgical techniques and their implications for guide-wire placement in patients are clearly displayed to the radiology professional.

As a precursor to the surgical guide-wire placement planning, three- dimensional object image data 98 of a region of interest of an object is provided in step a). The three-dimensional object image data 98 may come from a CT scan.

According to an embodiment, the three-dimensional object image data 98 of a region of interest of an object is reconstructed from a fusion of a 2D mammogram, and a biomechanical model which has been adapted to the information contained in the 2D mammogram.

This technique involves obtaining the three-dimensional outline of a patient's breast using, for example, a laser-measuring technique. A 2D mammogram of a patient's breast is taken. The outline of the patient's breast is input to the biomechanical breast model to provide a breast model which is customized to the patient's dimensions. Then, the biomechanical model is registered to the 2D mammogram image. The result of this procedure is a three-dimensional object image data of breast tissue.

The location of a target region 100 inside the region of interest of the three- dimensional object image 98 can be derived visually, for example, a medical professional can inspect a 2D mammogram for details of a lesion. The 2D coordinates registered to a datum on the 2D mammography image can be provided to give the location of a target region 100.

Finally, a set of generic surgical model information 102, wherein each generic surgical model represents a surgical protocol, is provided. The purpose of the generic surgical model is to provide a generalized display of surgical breast cancer removal techniques which are not customized to a patient.

According to an embodiment, a simple generic surgical model may be represented by a half-sphere. More complex generic surgical models are also known. The differences in each surgical protocol (for example, different incision locations, and the order of tissue removal) are easily visible to a medical professional on the generic surgical model, when displayed on a display screen.

Fig. 2 illustrates a generic surgical model for a lumpectomy operation. In a lumpectomy, a thin cylinder of tissue 46a is excised from a breast. This cylinder contains a cancerous lesion, and a safety margin to ensure that the entire lesion is removed. The location of a lesion inside the cylinder is shown using a guide-wire. Following a lumpectomy operation, the excised tissue is carefully x-rayed, with the guide-wire still in place, to ensure that all of the cancerous material has been removed.

In Fig. 2a, a generic surgical model 40 is illustrated in a plan view, and a side view is illustrated in a side view 40a. The components of the generic surgical model may be represented using a volumetric model. The generic surgical model 40 of the lumpectomy procedure defines, as a first step a), a single incision point 42, shown in the profile view as the line directed into the breast 42a. Moving to step b) of the generic surgical model, a substantially annular arc 44 has been created in the generic surgical model starting from the incision point 42. Any cancerous lesion would be denoted in the space inside the annular arc. Finally, in step c) of the lumpectomy generic surgical model, the cylinder of tissue containing the cancerous material has been withdrawn from the breast model 40 as denoted in feature 46a.

Fig. 2 does not illustrate guide-wire insertion but only illustrates the general lumpectomy procedure. Nevertheless, it is immediately apparent that if a guide-wire were hypothetically to be inserted in the space in the center of, and parallel to, lines 42a and 44a, then the annular incision 44 would be easy to make, because a scalpel would not collide with the guide-wire. This would be an example of good guide-wire positioning, in the context of a lumpectomy procedure.

Conversely, it could be imagined that a guide-wire could unintentionally be placed so as to bisect either, or both of lines 42a and 44a. If this was the case, then at a time when a surgeon came to make the annular incision 44, the guide-wire would cause the scalpel to be blocked, requiring the guide-wire to be adjusted during surgery, causing inconvenience to the surgeon, and potentially having adverse clinical consequences.

Fig. 3 indicates another surgical protocol known as a parallelogram mastopexy lumpectomy. In step a), two initial incision points 48 and 50 have been made, in step b), the provision of arcs 52 and 54 in between the initial incisions 48 and 50 is illustrated. In step c) of the surgical protocol, the tissue in between the two arcs has been excised as seen in wedge 56, leaving behind the void 58.

Fig. 4 illustrates another type of surgical protocol. In step a), incision points

60, 62 and 64 are defined. In step b), a first line 66 between incision 60 and 62 is shown and a second incision 68 between point 62 and 64. These incisions define a substantially sectoral region of the surgical model. In step c), the sector has been removed. This is known as an oncoplastic procedure.

In each of the three cases, illustrated above, it will be seen that a generic surgical model, is used to define the stages of a specific surgical protocol. Advantageously, such a model can be displayed in three dimensions in order to provide feedback information to a radiologist when deciding how to place a guide-wire.

Therefore, a generic surgical model from such a set of generic surgical models may be selected by a surgeon prior to a dissection procedure, dependent on the general type procedure deemed necessary by the surgeon.

According to an embodiment of the invention, there is a step of customizing the generic surgical model with information about a lesion location, and initial incision point information.

As discussed above, the method of surgical guide-wire placement planning comprises the step of aligning the three-dimensional object image data, the location of the target region, and the selected generic surgical model. According to an embodiment, the aligning may comprise three-dimensional image registration, to conform features of the generic surgical model to the three-dimensional object image data.

According to an embodiment of the invention, there is a step of feature extracting which extracts either automatically, or manually, the lesion and/or anatomical markers like the outline of the breast, the nipple, and the pectoralis muscle from a 2D mammogram image or the three-dimensional object image data. A step of model alignment aligns the selected generic surgical model to individual breast images of the patient.

Therefore, the generic surgical model (represented by a half-sphere, for example) is deformed in three dimensions so that it fits the three-dimensional object image data provided in step a). This creates a patient-customized surgical model, in which the steps outlined in Fig. 2, Fig. 3 or Fig. 4, can be represented according to the proportions, dimensions and image contents of the patient's breast.

According to an embodiment of the invention, the patient-customized surgical model may be displayed to a user, for example using a screen, or three-dimensional viewing glasses.

The generation of the patient-customized surgical model enables the planning of a guide-wire insertion path which does not collide with any required incision paths that the surgeon must make.

According to an embodiment of the invention, there is provided a step of inputting surgical margin information. The generation of the at least one guide-wire insertion path thereby includes the calculation of an additional safety-margin through which the guide- wire should not pass, to enable the surgical planning of a safety margin.

The generation of the at least one guide-wire insertion path may be manual. A user (such as a radiologist) may view on a screen the patient-customized surgical model (as a "still" 3D representation, an animated 3D representation, or a 2D "cut-through" view), and manipulate or place a guide-wire insertion path using an input means such as a computer mouse or a keyboard. The user may be able to drag around the placed guide-wire insertion path until it is suitably placed.

Alternatively, the generation of the at least one guide-wire insertion path may be effected using an automatic algorithm. The generation of the guide-wire insertion path may be viewed as a heuristic problem in three dimensions, in which the guide-wire must intersect with the location of the target region of a lesion, but must not stray too close to an incision path of the patient-customized surgical model. Many heuristic algorithms for searching for such an optimal guide-wire insertion path will be known to the person skilled in the art.

According to an embodiment of the invention, the heuristic search may additionally be bounded, to prevent a guide-wire path being generated which is too oblique (for example, entering the target at an opposite side of the breast to which a lesion is located).

According to an embodiment of the invention, the heuristic search may be partially bounded using "waypoints" which are placed by a user, with the intervening wire locations calculated by a search algorithm.

Finally, the at least one guide-wire insertion path is displayed, showing the path which is most suitable for insertion of the guide-wire into the object within the context of the patient-customized surgical model.

According to an embodiment of the invention, the insertion path is displayed on a display screen 96.

According to an embodiment of the invention, the three-dimensional object- image data represents a human breast.

According to an embodiment of the invention, there is provided a method of surgical guide-wire placement planning as described previously, wherein after step g), there are the steps of:

h) inserting the guide-wire into a treatment object according to the generated guide-wire insertion path;

i) imaging the guide-wire in its inserted position;

j) comparing the generated guide-wire insertion path with the image of the guide-wire in its placed position, wherein the comparison provides a guide-wire accuracy insertion metric.

According to this embodiment, radiology professional can ensure that the guide-wire has been placed in the correct position as calculated using the surgical and radiological planning workplace.

According to an embodiment of the invention, a method of surgical guide-wire placement planning is provided as previously described, wherein after step j), there is a step h):

h) projecting onto the treatment object a route-line representing the path of the guide-wire according to (i) its imaged position after insertion or (ii) the generated guide-wire insertion path. According to this embodiment, the radiology professional or the surgical professional may be assisted either during insertion of the guide-wire, or during surgery, respectively, with an optical trace representing a route-line of the guide-wire.

According to an embodiment of the invention, the alignment step is performed using elastic registration.

According to an embodiment of the invention, the method comprises after step e), the further steps of:

el) identifying anatomical datum points in the three-dimensional object image data;

e2) matching the identified anatomical datum points with corresponding datum points in the three-dimensional surgical model;

e3) performing the alignment of step e) using the matched anatomical datum points.

According to an embodiment of the invention, the method described above further comprises after step e) the further steps of:

e4) displaying the patient-customized surgical model to a user;

e5) inputting a guide-wire route manually according to boundaries specified in the generic surgical model;

e6) displaying the manually input guide wire route to the user;

According to an embodiment of the invention, the method described above further comprises in step a), the step al) of:

al) providing an initial guide-wire incision location; and in step f), the step: fl) using a three-dimensional heuristic search to calculate the at least one guide- wire insertion path using the boundary conditions of (i) the patient-customized surgical model (ii) the initial guide-wire incision location and (iii) the location of a target region inside the region of interest.

According to an embodiment of the invention, the method described above wherein in step fl), a plurality of guide-wire insertion paths are generated, and after step fl) there is the additional step f2) of:

f2) user selection of a path of the plurality of guide-wire insertion paths.

According to an embodiment of the invention, the method described above further comprises in step a), that the three-dimensional object image data of a region of interest of an object is provided by:

a2) providing a generic bio mechanical object model; a3) measuring the external contour of the region of interest of the object using optical metrology;

a4) generating the three-dimensional object image data by morphing the generic biomechanical model so that it conforms to the external contour measured in step a2).

According to an embodiment of the invention, the method described above further comprises, in step g), that the at least one guide-wire insertion path suitable for insertion of a guide-wire into the object is displayed on a screen of a medical imaging workstation.

Fig. 5 shows a medical image-processing device 10 for guide-wire placement planning according to an aspect of the invention. The device comprises:

an input unit 92;

a processing unit 94; and

an output unit 96.

The input unit 92 is configured to provide the processing unit 94 with three- dimensional object image data of a region of interest of an object, to provide a location of a target region inside the region of interest of the three-dimensional object image, and to provide a set of generic surgical model information, wherein each generic surgical model represents a surgical protocol.

The input unit is configured to receive at least three-dimensional object image data of a region of interest of an object 98, a location of a target region inside the region of interest of an object 100, and set of generic surgical model information 102.

The processing unit 94 is configured to select a generic surgical model from the set of generic surgical model information, to align the three-dimensional object image data, the location of the target region, and the selected generic surgical model using an image registration process to create a patient-customized surgical model, and to generate at least one guide-wire insertion path in the patient-customized surgical model.

The output unit 96 is configured to display the at least one guide-wire insertion path suitable for insertion of a guide-wire into the object.

Therefore, at least the patient-customized surgical model permits an improved exchange of information between a radiologist and a surgeon.

Fig. 6 shows a practical application of the device and method described above, as software modules running on computer systems. In Fig. 6 the first workstation 70 is shown with a surgical planning workplace displayed. The second workstation 72 is shown with a radiology planning workstation displayed. The first and second workstations are connected, to enable collaboration between a surgical professional, and a medical professional. It will be appreciated that the software could run on the same computer, rather than requiring two computers. Conventionally, the software would be in communication with a server via a network, or the internet as is known to those skilled in the art.

Alternatively, data can be transferred using CD-ROM, DVD, a USB stick, or other data transfer means.

The surgical planning workplace 70 allows the display and selection of a set of surgical procedures 72a, 72b, 72c, as discussed previously. Each procedure is described by a qualifier indicating its appropriate use. Qualifiers might, for example, be image-based information.

In the surgical planning workplace, the surgical protocol is represented by a 3D surgical model, which may be a standardized image-based breast model 73, such as a half-sphere, which indicates the surgical pathway, and the tissue that has to be excised.

A surgical procedure selector menu 75 allows the selection of an appropriate generic surgical procedure out of the set of predefined surgical procedures 72a, 72b, 72c.

According to an embodiment, the selection is performed manually by a surgeon.

According to an embodiment, the selection of the appropriate surgical procedure is performed automatically, based on a metric derived from an image analysis of a 2D mammogram image.

Finally, the surgical procedure selector allows the individualization of a selected surgical procedure by allowing an operator automatically or manually to align patient breast images to the selected surgical procedure, as represented by the 3D surgical model 73, by using tools from the image toolbox.

The radiology guide-wire workplace 72 comprises a guide-wire placement assistant 74 as a module of a radiology-planning software application. The guide-wire placement assistant displays the surgical procedure for a relevant patient, as previously defined by the surgeon in the surgical planning workplace.

The radiology planning workplace can optionally display the 3D surgical model (the standardized image-based breast model) 73 of the selected surgical procedure, and an overlay of the individualized surgical procedures on the selected breast images.

The radiology planning workplace also has tools for semi-automatic planning of guide-wire placement in terms of at least incision location, pathway, and depth of guide- wire placement. The planned guide-wire placement may be automatic, or it may be positioned manually using input means 70 such as a keyboard 76 or a mouse 78.

According to an embodiment, the radiology planning workplace allows the input of a post-placement mammogram, for comparison with the original guide-wire placement plan. Thus, the radiology planning workplace can provide feedback of the placement of the guide-wire and its deviation from the original surgical plan.

The screen of the radiology planning workplace displays the patient- customized surgical model 80 and aspects of the incision and removal of tissue 82 along with a guide-wire path 84.

According to an embodiment of the invention, the radiology plan showing the at least one guide-wire insertion path may be returned to the surgical planning workplace to enable a surgeon to confirm that a guide-wire placement plan is acceptable before the guide- wire is placed.

According to an embodiment of the invention, either the surgical planning workplace, or the radiology planning workplace, or both can be provided with a feature extraction means which extracts either automatically, or manually, the lesion and/or anatomical markers like the outline of the breast, the nipple, and the pectoralis muscle. The model aligner aligns the generic surgical model to the three-dimensional object data of the patient. Therefore, the guide-wire placement can be selected from a predefined set of plans of guide-wire placement by the radiologist. Alternatively, the guide-wire placement is edited by the radiology professional, using editing tools that assist the drawing of incision points, pathways, and target points in radiological images (either 2D or 3D) or breast diagrams. Alternatively, the guide-wire placement is calculated automatically by the guide-wire placement assistant. The radiologist is enabled to modify, correct, and approve the proposed guide-wire placement.

For displaying the guide-wire placement, a display plan of guide-wire placement on the screen of the workstation such as a radiology guide-wire workplace is possible. Alternatively, the planned guide-wire placement can be projected on the top of the patient's breast during surgical procedures. Finally, the deviation from the planned guide- wire placement or surgical plan can be shown as a distance from the target during the guide- wire placement, or as feedback from the guide-wire placement by comparing the result of the guide-wire placement and the planned guide-wire placement.

Therefore, an approach to planning guide-wire placement has been presented which enables better communication between the surgeon and a radiology professional. According to an embodiment of the invention, a medical image-processing device 90 is provided, wherein the generic surgical model comprises a three-dimensional surgical model comprising a plurality of three-dimensional segments representing areas of the region of interest of an object to be removed or retained, and surgical model metadata associated with the model selected from the group of:

(i) type of procedure,

(ϋ) number of incisions,

(iii) location, size, and orientation of incisions on the generic surgical model,

(iv) order of incisions,

(v) location of anatomical datum points on the three-dimensional surgical model,

(vi) safety margin, and

(vii) guide-wire type.

According to this embodiment, the generic surgical model may carry more details of surgical parameters of interest of surgeons which may be used to characterize further the generic surgical model, and therefore provide a more accurate patient-customized surgical model.

According to an embodiment of the invention, a medical- image processing device 90 is provided as previously described; wherein the alignment step is performed using elastic registration.

According to an embodiment of the invention, a medical-image processing device 10 as previously described is provided, wherein the processor 94 is further configured to identify anatomical datum points in the three-dimensional object image data, match the identified anatomical datum points with corresponding datum points in the three-dimensional surgical model, and perform the alignment using the matched anatomical datum points.

According to this aspect of the invention, image features which are palpable both in the three-dimensional object image data derived from a 2D mammogram, and which are present in a generic surgical model, are used to more accurately register the three- dimensional object image data and the generic surgical model.

According to an embodiment of the invention, the processing unit 94 is further configured to display the patient-customized surgical model to a user, input a guide-wire route manually according to boundaries specified in the generic surgical model, and display the manually input guide wire route to the user.

According to an embodiment of the invention, a medical image-processing device 90 as previously described is provided, wherein the input device 92 is configured to provide the processing unit 94 with an initial guide -wire incision location, and the processing unit 94 is configured to use a three-dimensional heuristic search to calculate the at least one guide-wire insertion path using the boundary conditions of (i) the patient-customized surgical model, (ii) the initial guide-wire incision location and (iii) the location of a target region inside the region of interest.

According to this embodiment, a user may select the guide-wire routes but receives visual feedback when the selected route exceeds the boundary conditions.

According to this embodiment, an optimal guide-wire route can be calculated using the patient-customized surgical model.

According to an embodiment of the invention, a medical image-processing device 94 is provided, wherein the processor 94 is configured to generate a plurality of guide- wire insertion paths, and the input device is configured to provide to the processing device 94 a user selection of a path of the plurality of guide- wire insertion paths.

According to this embodiment of the invention, several promising guide-wire insertion paths can be presented to the user for selection.

According to an embodiment of the invention, a medical image-processing device as described previously is provided. The input unit 92 is configured to provide the processing unit 94 with a generic bio mechanical object model, and the measurement of the external contour of the region of interest of the object derived using optical metrology.

The processing unit 94 is configured to generate the three-dimensional object image data of a region of interest of an object by generating the three-dimensional object image data by morphing the generic biomechanical model so that it conforms to the measured external contour.

According to this embodiment, a quasi-realistic model of the patient's breast may be provided simply using an optical depth measurement.

According to an embodiment of the invention, a medical image-processing device 90 as described previously is provided, wherein the display unit is configured to display the at least one guide-wire insertion path suitable for insertion of a guide-wire into the object on a screen of a medical imaging workstation.

According to an aspect of the invention, there is provided a medical imaging system 90 for guide-wire placement planning, comprising:

an image acquisition arrangement 92;

a medical image-processing device 94, and

a display unit 96. The medical imaging system 90 is configured to acquire image data from the image acquisition arrangement 92, and provide the data to the medical image-processing device 94.

According to an aspect of the invention, there is provided a computer program element for controlling a device as previously described, which, when being executed by the processing unit is adapted to perform the method steps discussed previously.

According to an aspect of the invention, there is provided a computer-readable medium having stored the computer program element described previously.

According to an embodiment of the generic surgical model comprises a three- dimensional surgical model comprising a plurality of three-dimensional segments

representing areas of the region of interest of an object to be removed or retained, and surgical model metadata associated with the model selected from the group of:

(i) type of procedure;

(ii) number of incisions;

(iii) location, size, and orientation of incisions on the generic surgical model;

(iv) order of incisions;

(v) location of anatomical datum points on the three-dimensional surgical model;

(vi) safety margin;

(vii) guide-wire type.

In another exemplary embodiment of the present invention, a computer program or a computer program element is provided that is characterized by being adapted to execute the method steps of the method according to one of the preceding embodiments, on an appropriate system.

The computer program element might therefore be stored on a computer unit, which might also be part of an embodiment of the present invention. This computing unit may be adapted to perform or induce a performing of the steps of the method described above. Moreover, it may be adapted to operate the components of the above described apparatus. The computing unit can be adapted to operate automatically and/or to execute the orders of a user. A computer program may be loaded into a working memory of a data processor. The data processor may thus be equipped to carry out the method of the invention.

This exemplary embodiment of the invention covers both, a computer program that right from the beginning uses the invention and a computer program that by means of an up-date turns an existing program into a program that uses the invention. Further on, the computer program element might be able to provide all necessary steps to fulfil the procedure of an exemplary embodiment of the method as described above.

According to a further exemplary embodiment of the present invention, a computer readable medium, such as a CD-ROM, is presented wherein the computer readable medium has a computer program element stored on it which computer program element is described by the preceding section.

A computer program may be stored and/or distributed on a suitable medium, such as an optical storage medium or a solid state medium supplied together with or as part of other hardware, but may also be distributed in other forms, such as via the internet or other wired or wireless telecommunication systems.

However, the computer program may also be presented over a network like the World Wide Web and can be downloaded into the working memory of a data processor from such a network. According to a further exemplary embodiment of the present invention, a medium for making a computer program element available for downloading is provided, which computer program element is arranged to perform a method according to one of the previously described embodiments of the invention.

It has to be noted that embodiments of the invention are described with reference to different subject matters. In particular, some embodiments are described with reference to method type claims whereas other embodiments are described with reference to the device type claims. However, a person skilled in the art will gather from the above and the following description that, unless otherwise notified, in addition to any combination of features belonging to one type of subject matter also any combination between features relating to different subject matters is considered to be disclosed with this application.

However, all features can be aligned providing synergetic effects that are more than the simple summation of the features.

While the invention has been illustrated and described in detail in the drawings and foregoing description, such illustration and description are to be considered illustrative or exemplary and not restrictive. The invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing a claimed invention, from a study of the drawings, the disclosure, and the dependent claims.

In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. A single processor or other unit may fulfil the functions of several items re-cited in the claims. The mere fact that certain features are re-cited in mutually different dependent claims does not indicate that a combination of these features cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.