A pedometer is a popular wearable sensor used to enumerate walking steps taken per day and in this way determines the approximate distance traveled. In this study, we used blood pressure and walking step data, obtained from 48 patients in a home healthcare system, to investigate the effectiveness of the pedometer in a clinical setting. Changes in blood pressure and walking steps per day were compared. Our results indicate that walking, as a regular form of exercise, contributed to lowering of blood pressure. Thus the pedometer is useful for improving the quality of life of patients in the home healthcare setting.

This paper proposes a 3-D cardiovascular modeling system based on neonatal echocardiographic images. With the system, medical doctors can interactively construct patient-specific cardiovascular models, and share the complex topology and the shape information. For the construction of cardiovascular models with a variety of congenital heart diseases, we propose a set of algorithms and interface that enable editing of the topology and shape of the 3-D models. In order to facilitate interactivity, the centerline and radius of the vessels are used to edit the surface of the heart vessels. This forms a skeleton where the centerlines of blood vessel serve as the nodes and edges, while the radius of the blood vessel is given as an attribute value to each node. Moreover, parent-child relationships are given to each skeleton. They are expressed as the directed acyclic graph, where the skeletons are viewed as graph nodes and the connecting points are graph edges. The cardiovascular models generated from some patient data confirmed that the developed technique is capable of constructing cardiovascular disease models in a tolerable timeframe. It is successful in representing the important structures of the patient-specific heart vessels for better understanding in preoperative planning and electric medical recording of the congenital heart disease.

This paper introduces a new design to allow interactive, direct manipulation of volume data on volumetrically rendered images. We present an adaptive volume proxy mesh which serves not to define surfaces, but to encode the geometry and physical state of the volume. This system performs a modeling-free form of direct volume deformation by adaptively constructing the whole geometric structure on the background while keeping the structure transparent to the user. A complex, high-frequency structure is locally encoded into the mesh on-the-fly based on the user's volume of interest. This paper also presents a scheme for volume shading/shadowing applied in combination with our framework for improving reality in the visualization of time-varying deformable objects. We demonstrate examples of geometry-encoded direct volume manipulation and application to volume exploration and surgical simulation.

This paper presents a new set of techniques by which surgeons can interactively manipulate patient-specific volumetric models for sharing surgical process. To handle physical interaction between the surgical tools and organs, we propose a simple surface-constraint-based manipulation algorithm to consistently simulate common surgical manipulations such as grasping, holding and retraction. Our computation model is capable of simulating soft-tissue deformation and incision in real time. We also present visualization techniques in order to rapidly visualize time-varying, volumetric information on the deformed image. This paper demonstrates the success of the proposed methods in enabling the simulation of surgical processes, and the ways in which this simulation facilitates preoperative planning and rehearsal.

This paper proposes vertex-preserving cutting methods on finite element models for interactive soft tissue simulation. Unlike existing methods, we aim to shape variety of incisions using only initial vertices of tetrahedral meshes. Neither tetrahedral decomposition nor vertex creation is used. The number of vertices is preserved. This avoids increase of computation cost as well as allows fast update of physical status of finite element models. To preserve 3D shape and sharp feature of initial meshes through on-the-fly mesh modification, constraints are introduced to the topological update scheme. In our model, the size of stiffness matrix is constant. Our framework efficiently simulates several varieties of smooth incisions with sufficient quality for surgical simulation, and also achieves interactive performance in complex meshes with thousands of elements.

The Hanshin-Awaji earthquake in January 1995 caused the greatest number of deaths and injuries in Japan since World War II. Various weaknesses of modern information systems were exposed during and after the earthquake. The authors carried out a questionnaire survey to investigate the current state of hospital information and to examine the kinds of information needed immediately after an earthquake. The survey results show that information about the ability to admit new patients and the availability of medical supplies is necessary immediately after such a disaster. These results will be useful for planning countermeasures against this kind of disaster.