Volume manipulation using CUT and PASTE operations
and its applications
Akio Doi1, Hiroki Takahashi1, Sachio Mega2, and Taro Mawatari3
1

1

Software and Information Science, Iwate Prefectural University, Japan2
Department of CG, JFP Corporation, Japan,
3
Hamanomachi Hospital, Japan

Introduction

With the advent of the aging society, knee and hip joint
diseases have increased rapidly in recently, and both Total
Knee Arthroplasty (TKA) and Total Hip Arthroplasty(THA) surgery are increasing. TKA and THA are surgical
techniques that replace the artificial component(assortment of implant) with knee and hip joint,respectively. The conventional preoperative planning uses
inferior limb X-ray images (Two-Dimensional Computed
Radiography images: 2D CR). That's because X-ray film
image in standing position contains the information
required for preoperative planning. Therefore, thetechniques and experiences of the surgeon cause a large
difference for precise position of implant and cutting boneplane, volume of cutting bone, and so on. In order tosolve the problems and to support the surgeon in apreoperative planning of TKA and THA, we havedeveloped a 3D based surgical planning system on apersonal computer. The system manipulates 3D templates
of TKA and THA components, and cut and paste bone
precisely on three-dimensional (3D) Computed
Tomography (CT) image. In this paper, we havedescribed the detail of interactive cutting and pasting
functions for 3D image, and we have applied them into
our 3D based surgical planning system. We also evaluate
our manipulation techniques by using several CT imageof patients.
2Multi-volume operation for 3D image

Simultaneous processing of CT and MR images, which are
different modality, is often used in clinical fields. CT canvisualize bones, such as a femur (thighbone) and a tibia, but it isdifficult to visualize cartilage (soft bones) in knee joint. Since
MRI can visualize cartilage region, both CT and MR images
will be utilized for preoperative planning of surgery. The
conventional 3D image processing manipulates a single 3Dimage. However, the advent of 64-bit OS (Operating System),and the improvements of CPU (Central Processor Unit) andGPU (Graphics Processor Unit), and large-capacity memory onCPU, make it possible to manipulate multiple 3D imagesimultaneously on a personal computer.
2.1
CUT operations using stroke
Commonly, a display monitor is used to deal with 3D objects
in 3D space. However, it is difficult and time consuming task toplace 3D objects in 3D space on a display monitor. Therefore,
we propose a tablet-based method to place 3D objects in 3Dspace. We utilize the directed line, we called stroke, on thescreen, and define the CUT surface in 3D space on a display

monitor. The image region is partitioned by the plane enclosed
in the line which gave the direction. The direction of line, wecalled stroke, represents the normal direction of cut plane, whichis positive or not. Here, we show several examples in theoperation. Front and back sides of the cut surface are defined by
the direction of the arrow (arranged in order of ①→②), as
shown in the figs 1 and 2.

Fig. 1 Placement (case A)

Fig. 2 Placement (case B)

If cut surface is single, the results shown in Figure 3 will besame, regardless of the front and back sides of the cut surface. Ifthe number of cut surface is two or more, the results will bechanged by a combination of front and back sides of each cut
surface. Also, the size of the cut surface will be treated as anextension that is present (dotted line in Figure 4) on the display
even shorter. Processing in the two cut surfaces is that we divide
into two separate regions, which are the region enclosed by thefront side of the faces, and other region. If two of the cut surface,
the direction of each segment in the stroke, you can specify thearea to be cut.

Fig. 3 Results (1)Fig. 4 Extended linesFig. 5 Two cut planes (1)Fig. 6 Results (2)Fig. 9 PASTE operation

Fig. 7 Two cut planes (2)Fig. 8 Results (3)2.2PASTE operation
PASTE operation has the ability to place two planes on thesame plane. For example, the two cut surfaces of the image
volume are pasted. This feature is used when both images needto connect each other, precisely. In our system, the user selecttwo cut surfaces interactively, and the first cut surface is relocated on the second cut surface. After the placement, thevolume image with first cut surface can be moved and rotatedhorizontally on other surface (Figure 9).
33D based surgi cal planning system

Our 3D based surgical planning system manipulates a multivolume data, and we have developed cut and paste operations toimprove the accuracy of surgical procedures. In addition, wehave supported several functions, such as DICOM image loader,volume rendering, image segmentation, implant placement (3DTemplating), drawing auxiliary lines, for assistance withpreoperative planning.
Our goal is that the whole procedure for the preoperativeplanning will be done within 30 to 40 minutes. Therefore, oursystem, unlike traditional CAD systems and CG system, hasbeen designed and implemented to allow, cut, move, rotate
objects with intuitive mouse-only operation. The mouse is suited
to intuitive operations for rotation and movement on a screen.
Each subset of several images is selected by the mouse, and theselected images can be moved and rotated interactively. Figure
10 shows the simulation results of the posterior rotational
osteotomy in clinical fields.
Our 3D based surgical system has been written by VC++ andOpenGL on Windows families, and our volume rendering
utilizes 3D texture function of OpenGL [2]. The gray-scaled
image has converted to color image, and stored as 3D texture
memory, and displayed by GPU.

Fig. 10 CUT and PASTE operations for 3D image
4Conclusion

The exact and efficient surgery planning increases the Quality
Of Life (QOL) of the patients, and reduces the burden ofsurgeons for the entire artificial joint surgery procedures. Oursystem manipulate 3D image directly, and CUT and PASTE
operations are very powerful tool for surgeons.
In this paper, we have described the detail of interactive
cutting and pasting functions for 3D image, and we have
implemented these functions into our 3D based surgicalplanning system.
The surgeons have evaluated ease of use of the manipulation
techniques by using several CT images of patients for TKA andTHA surgery. They have also used to several complicatedosteotomy surgery, such as the posterior rotational osteotomy
for the non-traumatic osteonecrosis of the femoral head.
Acknowledgements
Part of this research was conducted with a grant-in-aid for
Scientific Research (project number 23500562), and theresearch fund by the Japan Science and Technology Agency.
References[1][2]

M. Tokuda, A. Doi, F. Itoh, M. Suzuki, H. Haneishi, “ AnAutomatic Extraction of the Bone Axes of Femur and Tibia ofKnee Joint Using Inferior limb X -ray Image”, Journal of theInstitue of Image Electronics Engineers of Japan, Vol. 37, No. 4,
pp. 8-20, 2008.
A. Doi, T. Takahashi, T. Mawatari, and S. Mega, “Development ofa volume rendering system using 3D texture compression
techniques on general-purpose personal computer“, IEEE iCAST
2011, Dalian/China, 2011.