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We present a framework with two options for selecting a subgroup of training cases for intracranial aneurysm (IA) treatment. Option one, general training, describes training cases that represent a variety of different IAs that represent the diversity of real world cases. This can be achieved via instance selection (IS), which reduces size of a dataset by eliminating redundancies via outlier removal and clustering. Option two, a specific training scenario, describes training that is specialized based on IA features of a specific case, for which we present the novel reverse instance selection (RIS), which introduces similarity to the specific case to the IS methodology. We evaluated our IS and RIS by comparing them to subsets selected based on similarity (SIM) and random sampling (RndS). RIS outperformed SIM and RndS in 79% of experiments. IS outperformed RndS in 33% of experiments. In both scenarios, we observed that our approaches, which balance the weaknesses of SIM and RndS, perform best for small subset sizes close to the database cluster size. Our IS and RIS are flexible in regards to the underlying machine learning and weighting of metrics for evaluation, thus providing a way to select a representative and diverse subset not just for IAs, but also for different kinds of data.

We present a novel tool designed for the semiautomatic detection and assessment of prostate cancer during recurrence diagnostics using PET-CT with prostate-specific membrane antigen (PSMA). The tool automatically generates a structured report, which is enhanced by 3D images and ensures the reproducibility of the findings. Moreover, the area of the findings is automatically determined and can be corrected manually. Image data from 50 patients following radical prostatectomy was used. Our approach and its user interface were qualitatively evaluated by a nuclear medicine specialist. The segmentation analysis revealed a requirement for further automation. The resulting report was deemed highly beneficial, particularly in terms of the resulting reproducibility and the presentation of 3D images depicting the findings. The presented tool has great potential for much-needed support in everyday clinical practice, as it facilitates the communication of the diagnostic results to colleagues and patients and thus prevents misunderstandings.

Intracranial mirror aneurysms are pathologic dilatations of cerebral arteries that occur at identical locations in both hemispheres. They do not always have identical sizes, shapes, or rupture states, despite identical patient-specific risk factors. As a subgroup of multiple aneurysms and thus small amounts of data, clinical research about their causes and development has not been conclusive. Using eight patients with 16 mirror aneurysms with different rupture states, we investigated differences between the hemispheres. We virtually performed stitching: detaching the aneurysm domes to place them on the opposite parent vessel to assess the influence of aneurysm morphology and upstream parent vessel shape on hemodynamics. In the unaltered datasets, we found that blood flow within aneurysms in the left hemisphere has higher wall shear stress and velocity. After stitching, we found that both upstream parent vessel as well as aneurysm morphology influence hemodynamics. Morphologic parameters like size, undulation index, and aneurysm angle had a higher influence. In a short rupture risk analysis we found a correlation between rupture and aspect ratio and non-sphericity index. Overall, we found possible indicators for mirror aneurysm analysis that illustrated the importance of morphological analysis, though more datasets are necessary for conclusive statements about special treatment for mirror aneurysms.

Byline: G. Fusai (1), R. Steinberg (1), A. Prachalias (1), N. D. Heaton (1), L. Spitz (2), M. Rela (1) Keywords: Ex vivo; Extracorporeal; Ex situ; Pheochromocytoma; Bench surgery Abstract: A case of a 15-year-old girl with a malignant extraadrenal pheochromocytoma situated between the inferior vena cava and the portal triad is described. Using ex vivo technique, the tumour was successfully resected on the bench, as a previous attempt to remove the tumour in situ had been abandoned. The surgical aspects and implications of ex vivo surgery are discussed, highlighting the increased operative risk, perioperative mortality, and poor long-term results in patients with malignant tumours. Author Affiliation: (1) Institute of Liver Studies and Liver Transplant Surgical Service, King's College Hospital, Denmark Hill, SE5 9RS, London, UK (2) University Department of Paediatric Surgery, Great Ormond Street Hospital, London, UK Article History: Registration Date: 11/03/2005 Accepted Date: 16/07/2004 Online Date: 22/11/2005

Aims: To compare the long term functional and psychosocial outcomes following surgical treatment for total colonic aganglionosis (TCA) with those in an age and gender matched group of patients with [...]

A method is reported to determine the phase and amplitude of sinusoidally modulated event rates, binned into four bins per oscillation, based on data generated at the resonant neutron spin‐echo spectrometer RESEDA at FRM‐II. The presented algorithm relies on a reconstruction of the unknown parameters. It omits a calculation‐intensive fitting procedure and avoids contrast reduction due to averaging effects. It allows the current data acquisition bottleneck at RESEDA to be relaxed by a factor of four and thus increases the potential time resolution of the detector by the same factor. The approach is explained in detail and compared with the established fitting procedures of time series having four and 16 time bins per oscillation. In addition the empirical estimates of the errors of the three methods are presented and compared with each other. The reconstruction is shown to be unbiased, asymptotic and efficient for estimating the phase. Reconstructing the contrast increases the error bars by roughly 10% as compared with fitting 16 time‐binned oscillations. Finally, the paper gives heuristic, analytical equations to estimate the error for phase and contrast as a function of their initial values and counting statistics. [ABSTRACT FROM AUTHOR]