@TechReport{TR079,
  author =	 "Georg Langs and Horst Bischof and Philipp
                  L. Peloschek",
  title =	 "Automatic {Q}uantification of {D}estructive {C}hanges
                  {C}aused by {R}heumatoid Arthritis",
  institution =	 "PRIP, TU Wien",
  number =	 "PRIP-TR-079",
  year =	 "2003",
  url =		 "https://www.prip.tuwien.ac.at/pripfiles/trs/tr79.pdf",
  abstract =	 "Rheumatoid arthritis is an incurable disease a
                  ecting predominantly peripheral joints of the
                  appendicular skeleton. It can lead to severe
                  disabling mutilations and even to the complete
                  destruction of the joints. The accurate and
                  reproducible quantification of the progression of
                  the disease and of the destructive changes caused to
                  the joints is a decisive factor during therapy and
                  during clinical trials. The manual quantification
                  methods are time consuming and lack accuracy as well
                  as reproducibility. In this thesis an alternative
                  approach to automatically quantify the destructive
                  changes caused by rheumatoid arthritis is
                  proposed. Based on a hand radiograph the positions
                  of the bones and joints are determined by local
                  linear mapping nets. They learn the visual
                  appearance as well as the anatomical structure of
                  the hand during a training phase. The ability to
                  learn makes a straightforward transfer of the method
                  to other anatomical structures possible. Based on
                  the coarse position estimates of the bones, the
                  contour is identified with active shape models and
                  snakes. When these methods are combined in the ASM
                  driven snakes algorithm, a control of a priori
                  knowledge utilized during the search for the
                  pathologically changed contour is possible. The
                  resulting description and visual information of the
                  bone contour and its surroundings are used for point
                  wise classification of the contour with respect to
                  the question whether or not individual points are a
                  ected by rheumatoid arthritis. The automatic
                  determination of the extent of erosions in the joint
                  region allows for an accurate and operator
                  independent quantification of the disease
                  progression.",
}