Gregory J. Wiet

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Advanced display technologies have made the virtual exploration of relatively complex models feasible in many applications. Unfortunately, only a few human interfaces allow natural interaction with the environment. Moreover, in surgical applications, such realistic interaction requires real-time rendering of volumetric data-placing an overwhelming(More)
The Temporal Bone Dissection Simulator is an ongoing research project for the construction of a synthetic environment suitable for virtual dissection of human temporal bone and related anatomy. Funded by the National Institute on Deafness and Other Communication Disorders (NIDCD), the primary goal of this project is to provide a safe, robust, and(More)
PURPOSE Automatic scoring of resident performance on a virtual mastoidectomy simulation system is needed to achieve consistent and efficient evaluations. By not requiring immediate expert intervention, the system provides a completely objective assessment of performance as well as a self-driven user assessment mechanism. METHODS An iconic temporal bone(More)
PURPOSE Development of a visualization system that provides surgical instructors with a method to compare the results of many virtual surgeries (n > 100). METHODS A masked distance field models the overlap between expert and resident results. Multiple volume displays are used side-by-side with a 2D point display. RESULTS Performance characteristics were(More)
The intra-cochlear distributions of aspartate aminotransferase and glutaminase, prominent enzymes of aspartate and glutamate metabolism, have been studied by quantitative microchemical techniques. Also measured was choline acetyltransferase, the enzyme synthesizing acetylcholine, and a marker for the olivocochlear bundle. Aspartate aminotransferase activity(More)
To further investigate the peculiar characteristics of the middle ear and extraocular muscles, compared to the extensively studied skeletal muscles of the limbs, activities of enzymes of transmitter and energy metabolism were measured in homogenates of these muscles from albino and pigmented rats. These activities were compared to those for a masticatory(More)
Results Human cochlear normally has two and half turns. A pathological sample of a three-turn cochlea was sliced into 230 slides more than thirty years ago. Summary and Ongoing Work We present a pipeline for automatic registration of large set of microscopic images. We use a graph theoretical approach to match high-level features between consecutive(More)
We describe the use of the weighted distance transform (WDT) to enhance applications designed for volume visualization of segmented anatomical datasets. The WDT is presented as a general technique to generate a derived characteristic of a scalar field that can be used in multiple ways during rendering. We obtain real-time interaction with the volume by(More)