Title : Compression for 3-D Medical Images, with special concern on Virtual Colonoscory Name : Salih Burak Gokturk, gokturkb@stanford.edu Description : The medical images consist of three dimensional volumes. An abdomen CT scan contains 512x512x300 voxels in average, where each voxel is coded by 16 bits. In other words, the medical information for one individual is 150MB. This fact shows the obvious necessity of compression in medical images. On the other hand, the number of recent papers in literature is too few, and a generic compression method has not been set up. The main property of medical images is smoothness. The amount of change inter and intra slices is really small. On the other hand, this change spreads to the whole image, as opposed to a little portion in movies, so MPEG is probably not the right choice for medical images. In this project, I will be concentrating on applying the common compression methods to 3-D medical volumes. These will include lossless coding[3], vector quantization, transform coding and if time permits wavelet coding[2]. I would like to focus mainly on colon images. Virtual colonoscopy is a new branch of science for the computer aided detection of colon cancer. This branch of science started first by visualization. The next and current step is automated detection of colon cancer[1]. I feel that in the near future, a need for compression will occur. The final step of my project will be a knowledge based compression scheme. For this purpose, a radiologist will be contacted and asked about the redundant portions of CT abdomen volumes for virtual colonoscopy. Next, a compression scheme that uses this information will be applied. Tentative Schedule : Nov.6 - Nov.13 : Gathering the medical data. Formating the data into a matlab readable format. Application of lossless coding, Vector Coding, DCT based transform coding. Nov.13-Nov.20 : Meeting with the radiologist. Design of of knowledge based transformation. Applying wavelet based transform (if time permits) Nov.20-Nov.27 : Application of the knowledge based compression scheme. Nov 27 Dec1 : Report and presentation generation. References: [1] A graph Memhod for conservative detection of polyps by Salih Burak Gokturk, Carlo Tomasi, Proceedings of 2nd International Symposium on Virtual Colonoscopy, Boston, 2000,page 105. [2] Coding of 3D medical images using 3D wavelet decompositions by Baskurt, A.; Peyrin, F.; Benoit-Cattin, H.; Goutte, R. Acoustics, Speech, and Signal Processing, 1993. ICASSP-93., 1993 IEEE International Conference on Volume: 5 , 1993 , Page(s): 562 -565 vol.5 [3] Information preserved guided scan pixel difference coding for medical images by Takaya, K.; Tannous, C.G.; Li Yuan WESCANEX 95. Communications, Power, and Computing. Conference Proceedings., IEEE Volume: 1 , 1995 , Page(s): 238 -243 vol.1