Workstation Software Research Articles

Diagnostic Accuracy of an iPhone DICOM Viewer for the Interpretation of Magnetic Resonance Imaging of the Knee

To evaluate the diagnostic performance of viewing magnetic resonance (MR) images on a handheld mobile device compared with a conventional radiology workstation for the diagnosis of intra-articular knee pathology. Prospective comparison study. Tertiary care center. Fifty consecutive subjects who had MR imaging of the knee followed by knee arthroscopy were prospectively evaluated. Two musculoskeletal radiologists independently reviewed each MR study using 2 different viewers: the OsiriX DICOM viewer software on an Apple iPhone 3GS device and eFilm Workstation software on a conventional picture archiving and communications system workstation. Sensitivity and specificity of the iPhone and workstation interpretations was performed using knee arthroscopy as the reference standard. Intraobserver concordance and agreement between the iPhone and workstation interpretations were determined. There was no statistically significant difference between the 2 devices for each paired comparison of diagnostic performance. For the iPhone interpretations, sensitivity ranged from 77% (13 of 17) for the lateral meniscus to 100% (17 of 17) for the anterior cruciate ligament. Specificity ranged from 74% (14 of 19) for cartilage to 100% (50 of 50) for the posterior cruciate ligament. There was a very high level of interobserver and intraobserver agreement between devices and readers. The iPhone reads took longer than the corresponding workstation reads, with a significant mean difference between the iPhone and workstation reads of 3.98 minutes (P < 0.001). The diagnostic performance of interpreting MR images on a handheld mobile device for the assessment of intra-articular knee pathology is similar to that of a conventional radiology workstation, however, requires a longer viewing time. Timely and accurate interpretation of complex medical images using mobile device solutions could result in new workflow efficiencies and ultimately improve patient care.

Desempeño predictivo y clínico de un dispositivo target-controlled infusion para sevofluorano en una estación de trabajo convencional: correlación farmacocinética del modelo empleado

IntroductionGood governance of resources and global warming has attracted interest on minimal flow (0.3–0.5 l/min) inhalation anesthesia. ObjectivesTo evaluate the predictive and clinical performance of a TCI (Target-controlled infusion) device, and its pharmacokinetic correlation for sevoflurane. MethodsProspective, longitudinal, and analytical study on 25 adult patients. Fresh gas flow used 0.5 l/min. Target concentration of 1.2% (v/v). Continuous and variable infusion into the circuit of the anesthesia workstation. Controller developed with LABVIEW 6.1. Hemodynamic, respiratory and anesthetic depth data collected every 5 s using the anesthesia workstation software. Bias (MDPE%), inaccuracy (MDAPE%), wobble, and divergence of the TCI device were determined in the first hour. STATA-12 pk collapse was used to analyze the area under the curve of the target and expired concentrations. The results are expressed as Mean (CI 95%) and Median [IQR]*. ResultsTarget concentration used 1.22 [1.14–1.37] %*, reached in 04:07 [03:15–06:15]* min:s (expiratory branch). Anesthetic duration 1:10:50 (00:56:57–1:24: 43) h:min:s. Sevoflurane consumption 6.9 (5.7–8.0) ml. MDPE% −12.8 (−17.6 to −8.1) %; MDAPE% 15.9 (11.9–19.8) %; wobble 6.9 (5.0–8.7)% and divergence 0.89% (−5.96 to 7.7)%h-1. Interactions per hour on the TCI of 3 (2–4). Correlation of the area under the curve, Spearman's rho = 0.8577, p < 0.00001. ≥15% inaccuracy was associated with age >65 years and obesity. ConclusionsThe TCI sevoflurane© showed good performance, and the target concentration was rapidly reached and remained stable, with few interactions with the device needed during the first hour. There were neither overdosing nor clinically significant alterations.

Predictive and clinical performance of a TCI device for sevoflurane at a conventional workstation: Pharmacokinetic correlation of the model used

IntroductionGood governance of resources and global warming has attracted interest on minimal flow (0.3–0.5l/min) inhalation anesthesia. ObjectivesTo evaluate the predictive and clinical performance of a TCI (Target-controlled infusion) device, and its pharmacokinetic correlation for sevoflurane. MethodsProspective, longitudinal, and analytical study on 25 adult patients. Fresh gas flow used 0.5l/min. Target concentration of 1.2% (v/v). Continuous and variable infusion into the circuit of the anesthesia workstation. Controller developed with LABVIEW 6.1. Hemodynamic, respiratory and anesthetic depth data collected every 5s using the anesthesia workstation software. Bias (Median of Predictive Error, MDPE%), inaccuracy (Absolute Mean of Predictive Error, MDAPE%), wobble, and divergence of the TCI device were determined in the first hour. STATA-12 pk collapse was used to analyze the area under the curve of the target and expired concentrations. The results are expressed as mean (95% CI) and median [IQR]*. ResultsTarget concentration used 1.22 [1.14–1.37]%*, reached in 04:07 [03:15–06:15]* min:s (expiratory branch). Anesthetic duration 1:10:50 (00:56:57–1:24: 43) h:min:s. Sevoflurane consumption 6.9 (5.7–8.0) ml. MDPE% −12.8 (−17.6 to −8.1) %; MDAPE% 15.9 (11.9–19.8) %; wobble 6.9 (5.0–8.7)% and divergence 0.89% (−5.96 to 7.7)%h-1. Interactions per hour on the TCI of 3 (2–4). Correlation of the area under the curve, Spearman's rho=0.8577, p<0.00001. ≥15% inaccuracy was associated with age >65 years and obesity. ConclusionsThe TCI sevoflurane© showed good performance, and the target concentration was rapidly reached and remained stable, with few interactions with the device needed during the first hour. There were neither overdosing nor clinically significant alterations.

SU‐E‐J‐26: Analysis of Image Quality in CBCT QA Using a Treatment Planning System

Purpose:The objective of this study is to propose an alternative QA technique that analyzes imaging quality(IQ) in CBCT‐QA processing.Methods:A catphan phantom was used to take CT imaging data set that were imported into a treatment planning system – Eclipse. The image quality was analyzed in terms of in‐slice geometry resolution, Hounsfield numbers(HU) accuracy, mean‐slice thickness, edge‐to‐center uniformity, low contrast resolution, and high contrast spatial resolution in Eclipse workstation. The CBCT‐QA was also analyzed by OBI‐workstation and a commercial software. Comparison was made to evaluation feasibility in a TPS environment.Results:The analysis of IQ was conducted in Eclipse v10.0 TPS. In‐slice geometric resolution was measured between 2‐rods in section CTP404 and repeated for all 4 rods with the difference between expected and measured values less than +/−0.1 cm. For HU, the difference between expected and measured values in HU was found much less than +/−40. Mean slice thickness measured by a distance on the wire proportional to scanner increment multiplying by a factor of 0.42. After repeating measurements to 4 wires, the average difference between expected and measured values was less +/−0.124 mm in slice thickness. HU uniformity was measured in section CTP486 with the tolerance less than +/−40 HU. Low contrast resolution in section CTP515 and high contrast resolution in section CTP528 were found to be 7 disks in diameter of 4 mm and 6 lp/cm, respectively. Eclipse TPS results indicated a good agreement to those obtained in OBI workstation and ImagePro software for major parameters.Conclusion:An analysis of IQ was proposed as an alternative CBCT QA processing. Based upon measured data assessment, proposed method was accurate and consistent to IQ evaluation and TG142 guideline. The approach was to utilize TPS resource, which can be valuable to re‐planning, verification, and delivery in adaptive therapy.

Model-based Automatic Segmentation Algorithm Accurately Assesses the Whole Cardiac Volumetric Parameters in Patients with Cardiac CT Angiography: A Validation Study for Evaluating the Accuracy of the Workstation Software and Establishing the Reference Values

The cardiac chamber volumes and functions can be assessed manually and automatically using the current computed tomography (CT) workstation system. We aimed to evaluate the accuracy and precision and to establish the reference values for both segmentation methods using cardiac CT angiography (CTA). A total of 134 subjects (mean age 55.3 years, 72 women) without heart disease were enrolled in the study. The cardiac four-chamber volumes, left ventricular (LV) mass, and biventricular functions were measured with manual, semiautomatic, and model-based fully automatic approaches. The accuracies of the semiautomated and fully automated approaches were validated by comparing them with manual segmentation as a reference. The precision error was determined and compared for both manual and automatic measurements. No significant difference was found between the manual and semiautomatic assessments for the assessment of all functional parameters (P > .05). Using the manual method as a reference, the automatic approach provided a similar value in LV ejection fraction and left atrial volumes in both genders and right ventricular (RV) stroke volume in women (P > .05), with some underestimation of RV volume (P < .001) and overestimation of all remaining parameters (P < .05) in both genders. In addition, a significantly higher precision with a considerable association in intermeasurement (reproducibility) was observed using the automated approach. The model-based fully automatic segmentation algorithm can help with the assessment of the cardiac four-chamber volume and function. This may help in establishing reference values of functional parameters in patients who undergo cardiac CTA.

Software usage for synthesized sound in acoustics education

Musical acoustics engages students of many backgrounds when studying acoustics. Free software in the form of digital audio workstations can be used to provide students with a hands-on instruction to concepts of synthesis. Students can easily manipulate variables to add or detract from the realism of synthesized sound. This process of synthesizing sound provides a means for students to understand the concepts of additive and subtractive synthesis, attack and decay times, reverberation times, and filters. Application of free digital audio workstation software in an undergraduate class at Brigham Young University and in the recently revamped ASA Outreach workshop will be discussed.

Replacement of Professional Photogrammetric Workstations with Low Cost or Free of Charge Photogrammetric Software and Services for Image Triangulation and Image Matching

In the modern context of digital technology in the field of surveying and mapping, the technique of digital photogrammetry plays crucial role in all steps of mapping. There are some very expensive as well as low cost and free softwares are available in the market for professional photogrammetric work stations. The image triangulation and image matching is one of the very important steps of photogrammetry for which LPS as a commercial software is available in market. There are some low cost and free software as 123D Catch and Patch Boased Multi View Stereo Softwear (PMVS) also available. So, this paper mainly deals with the accuracy as well as the performance of those software for aerial triangulation and image matching for airborne image data to substitute commercial software for photogrammetric workstations. The accuracy assessment of image orientation, points cloud as well as DSM generated from those points cloud are also performed and compared with all products of LPS as commercial software. Nepalese Journal on Geoinformatics -12, 2070 (2013AD): 42-48

Magnetic Resonance Imaging as a Useful Tool in the Evaluation of Clinical Treatment of Otospongiosis

Objectives: Evaluate the applicability of magnetic resonance imaging (MRI) as a method for monitoring the activity of otospongiotic lesions before and after clinical treatment. Methods: Prospective, randomized, controlled, double- blind study involving 31 patients with clinical, audiometric, and tomographic diagnosis of otosclerosis. If computed tomography (CT) demonstrated active lesions, these patients underwent (MRI) in order to detect otospongiotic foci, seen as areas of gadolinium enhancement. Patients were divided into three groups and received treatment with placebo, alendronate sodium, or sodium fluoride for 6 months. After this period, clinical and audiometric evaluations and a second MRI were performed. The MRIs were evaluated by both a neuroradiologist and an otolaryngologist in a subjective (visual) and objective (using specific eFilm Workstation software) manner. Outcomes were assessed by comparing the MRI, clinical, and audiometric evaluations in the pre- and post-treatment periods. Results: Otospongiosis was most predominantly identified in the region anterior to the oval window (RAOW), and this site was reliable for comparing pre- and post-treatment scans. The patients in the alendronate and sodium fluoride groups had MRI findings that suggested a decrease in activity of otospongiotic lesions, more relevant in the alendronate group. These findings were statistically significant for both subjective and objective MRI evaluations. Conclusions: MRI shows higher sensitivity for detecting reduction in inflammatory activity of otospongiosis compared to clinical and audiometric findings. The objective MRI evaluation was the most accurate method of monitoring clinical treatment response in otospongiosis.

AB1273 Virtual anatomy of cervical nerve roots by 3-D MRI/CT fusion imaging

BackgroundBoth CT and MRI are widely known to be important tools in diagnosing spinal disorders. However, even when three-dimensional data are collected, images are often presented in two dimensions and...

Abstract 979: Paclitaxel resistance in prostate cancer: rescue of resistance using HDAC inhibitor SAHA involves apoptosis.

Abstract Introduction and Objective: Although Paclitaxel has demonstrated antitumor activity against several cancers, the acquisition of resistance during treatment remains a significant problem. Several potential mechanisms were proposed and the recent studies determined that drug resistance may involve histone H3 acetylation. Histone deacetylases (HDACs) are overexpressed in prostate cancer (PCa) and HDAC inhibitors have greater anti-proliferative activity against prostate and breast cancer models. We have investigated the interaction of the HDAC inhibitors Valproic Acid (VPA) and SAHA (Vorinostat) with Paclitaxel in both susceptible and resistance PCa cell lines. We evaluated anti-proliferative activity, nuclear morphometry, expression of apoptotic genes: Caspases 3 and 9 and Annexin A5, and three keratins (8, 18 and 19) which are involved in cell differentiation. Methods: Four PCa cell lines PC3, PC3-TxR (Paclitaxel resistant), DU145 and DU145-TxR (Paclitaxel resistant) were grown in 96 well &amp; 24 well tissue culture plates. After a day, the cells were exposed to 1.2mM of VPA and 5μM of SAHA for 24 hours followed by treatment with 4.5nM Paclitaxel for 48 hours. WST-1 cytotoxicity assay was performed in the 96 well plates. From the 24 well plates, RNA was isolated and the real-time PCR for expression of specific genes was done using gene specific primers and β-actin (to calculate relative expression). Nuclear morphometry was done in Feulgen stained nuclei using AutoCyteTM Pathology Workstation and QUIC-DNA software. Results: We found after 24hrs treatment: (i) VPA (1.2mM) reversed Paclitaxel resistance only in PC3 cell lines (50%) while (ii) SAHA made all the PCa cell lines more susceptible to Paclitaxel (50-60%). We observed specific changes in DNA ploidy and in nuclear structure in Paclitaxel resistant DU145-TxR cell lines when compared to DU145 cells. Our results showed different patterns of apoptotic and keratin gene expression occurred in DU145 and DU145-TxR cell lines following treatment with SAHA but no significant changes in PC3 and PC3-TxR cell lines. Expressions of Caspase 3, Caspase 9 and Annexin A5 were increased significantly in SAHA treated DU145-TxR cells, and KRT-8 and KRT-19 (keratins) were significantly downregulated in DU145-TxR cell lines irrespective of treatment. Conclusions: Hence, resistance to Paclitaxel can be rescued by HDAC inhibitors VPA and SAHA, but likely by different mechanisms that are yet to be established. Also, altered expression of apoptotic biomarkers, but not keratins shows that the rescue by SAHA involves apoptosis but not epithelial mesenchymal transition. Source of funding: National Cancer Institute of the National Institutes of Health through awards funded under Grant number 1U54CA143868-03 Citation Format: Christhunesa S. Christudass, Karan Sood, David Yeater, Robert W. Veltri. Paclitaxel resistance in prostate cancer: rescue of resistance using HDAC inhibitor SAHA involves apoptosis. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 979. doi:10.1158/1538-7445.AM2013-979

Towards Generic Embedded Multiprocessing for RVC-CAL Dataflow Programs

Dataflow languages enable describing signal processing applications in a platform independent fashion, which makes them attractive in today's multiprocessing era. RVC-CAL is a dynamic dataflow language that enables describing complex data-dependent programs such as video decoders. To this date, design automation toolchains for RVC-CAL have enabled creating workstation software, dedicated hardware and embedded application specific multiprocessor implementations out of RVC-CAL programs. However, no solution has been presented for executing RVC-CAL applications on generic embedded multiprocessing platforms. This paper presents a dataflow-based multiprocessor communication model, an architecture prototype that uses it and an automated toolchain for instantiating such a platform and the software for it. The complexity of the platform increases linearly as the number of processors is increased. The experiments in this paper use several instances of the proposed platform, with different numbers of processors. An MPEG-4 video decoder is mapped to the platform and executed on it. Benchmarks are performed on an FPGA board.

Vector mode based hardware acceleration and emulation for LDPC application

PurposeWith the rapid development of integrated circuits, verification of SOC chips has become a great challenge due to its integration and complexity. Traditional software‐based simulation methodology cannot meet verification needs. Therefore, FPGA‐based hardware acceleration technologies are requested in SOC verification. The classic methodology of hardware acceleration downloads the DUT (Device under Test) to the FPGA, while part of RTL codes and test bench is still run on the simulator in the workstation. Research found that the speed bottleneck of this methodology is mostly caused by the ping‐pong mode of data transmission between workstation software and the FPGA emulator, thus resulting in that channel transmission time takes too much proportion of total time. The purpose of this paper is to present a vector mode based hardware/software co‐emulation methodology, which leverages a pipeline structure to transmit, receive and buffer data. This methodology reduces the communication overhead by carrying out a parallel mechanism in that while user's design is under test in the emulator, signal data are transmitting in the channel simultaneously, thus increasing the speed of hardware acceleration and emulation.Design/methodology/approachThe methodology of hardware acceleration proposed by this paper intercepts data for once from the emulation process of a traditional platform as test bench and utilizes direct memory access (DMA) channel to speed up data transfer, as well as increasing reasonable data caching mechanism, which reduces the ratio of channel transmission time in the entire emulation time, achieving accelerating emulation.FindingsThe proposed methodology and traditional hardware acceleration approach were tested on a quasi‐cyclic low‐density parity‐check (LDPC) decoder. Experiment results indicate that the proposed method can increase communication throughput 140 times compared with the traditional approach.Originality/valueA vector mode based hardware/software co‐emulation methodology is presented in the paper. Higher communication throughput can be achieved by carrying out a parallel mechanism, as well as leveraging a pipeline structure to transmit, receive and buffer data.

High field magnetic resonance background suppression diffusion imaging in the diagnosis of liver foci of space occupying lesion

To explore the diagnostic value of the 3.0T magnetic resonance liver diffusion weighted imaging with background suppression (DWIBS) in liver foci of space occupying lesion. A total of 43 cases of liver bureau stove perch pathological change were included: 15 were hepatocellular carcinoma (HCC) with 24 lesions; 7 were liver metastatic tumor with 13 lesions; 10 were liver hemangioma with 12 lesions; and 11 liver cyst with 20 lesions. After taking the conventional T1WI and T2WI sequence, the magnetic resonance background suppression diffusion imaging technology (diffusion weighted imaging with background suppression, DWIBS) was applied, following the dynamic enhanced scan. With the MRI to DWIBS workstation for classifying positron emission computed tomography (PET) processing, the T2WI diagram and dynamic enhanced diagram were compared respectively for the 3 sequences of lesion detection rate, T2WI, and DWIBS, to enhance the delay time between the two joint and combined lesion detection rate. With the MRI workstation software scanning image generation ADC diagram, the ADC values were measured for liver cancer, liver metastatic tumor, liver hemangioma and liver cysts. The 3 sequences of detection rates of the T2WI, DWIBS and enhanced delay period T1WI were 91.3%, 94.2%, and 95.6%. The detection rate of DWIBS plus T2WI was 92.7%; that of T2WI plus enhanced delay time was 94.9%, and that of DWIBS plus enhanced delay time was 96.3%, with the rate of DWIBS plus enhanced delay period obviously higher than that of the DWIBS plus T2WI (P<0.05). The ADC value of the benign liver tumor was obviously higher than that of the malignant tumors: hepatic cyst (2.614 ± 0.57)×10⁻³ mm²/s, liver hemangioma (2.055 ± 0.21)×10⁻³ mm²/s, metastatic carcinoma (1.374 ± 0.32)× 10⁻³ mm²/s, and liver cancer (1.287 ± 0.14)×10⁻³ mm²/s. Except for the liver cancer and the liver metastatic tumor, there was significant difference between the other groups (P<0.05). Combing the DWIBS technology, the PET-like images and the ADC value acquired, the combined enhanced sequences could further facilitate the demonstration of the liver foci of space occupying lesion, the accuracy of identification and diagnosis of the liver foci of space occupying lesion.

Early Changes in Tissue Perfusion After Tissue Plasminogen Activator Administration in Hyperacute Ischemic Stroke: Initial Experiences With Arterial Spin Labeling Perfusion Magnetic Resonance Imaging

Cerebral perfusion monitoring is an important component of hyperacute stroke treatment. Arterial spin labeling (ASL) perfusion magnetic resonance (MR) imaging provides a noninvasive method of cerebral perfusion observation. Rapid changes in cerebral perfusion were demonstrated in two patients admitted one hour after onset of hyperacute stroke who underwent recombinant tissue plasminogen activator (rt-PA) treatment. Serial MR images and ASL images were taken on admission and after rt-PA administration. Cerebral blood flow (CBF) values were obtained using the CBF workstation and analysis software. Interpretable ASL images were taken in both patients. Perfusion deficits were consistent with symptoms and/or MR angiography imaging abnormalities. Delayed arterial transit effect was present in one patient; serial imaging showed improvement of CBF after rt-PA treatment in both patients. ASL perfusion MR imaging can provide rapid noninvasive multislice imaging in hyperacute ischemic stroke, and can depict early perfusion deficit and quantify regional CBF concomitantly.

3D Anatomy of the Cochlea for Cochlear Implant

Objective: This study aimed to create a 3-dimensional anatomy of the round window to hook region to identify the optimal site for cochleostomy in cochlear implantation and other endocochlear surgical procedures. Method: Ten normal ears were studied. To develop 3-dimensional reconstructed inner ear image based on high-resolution temporal bone images obtained by a spiral CT. The axial data were applied to create 3-dimensional images on the CT work station for post-processing with the use of current workstation software (GE Advantage Navigation). Results: The anatomy of the round window to hook region is complex, and spatial relationships can be difficult to evaluate using 2-dimensional CT images. Three-dimensional models of the round window membrane (RWM), cochlear duct, scala vestibule, scala tympani, ductus reuniens, and surrounding structures were generated. The relationship between these structures and the round window membrane (RWM) and adjacent otic capsule was easily identified. Conclusion: This 3-dimensional model has implications for surgical procedures to the inner ear that aim to minimize insertional trauma and decrease operation time. We can know the anatomic information before cochlear implant.

The diameter of the common bile duct in an asymptomatic Taiwanese population: Measurement by magnetic resonance cholangiopancreatography

BackgroundMagnetic resonance cholangiopancreatography (MRCP) is a popular modality for evaluation of the biliary tract, yet there is no data on the normal common bile duct (CBD) size of the average Taiwanese adult. This study attempts to establish a reference range for CBD diameter for the Taiwanese population. MethodsOver a 2-year period, all adults who underwent abdominal magnetic resonance imaging for health screening were recruited into the study. Patients with a prior history of hepatobiliary surgery and other significant morbidity were not included. Patients who were found to have abnormal liver function test results or abnormal imaging findings were also excluded from the study. After the patients fasted for a minimum of 8 hours, MR imaging was performed with a 1.5 T MR imager using a phased-array coil. Breath-hold thick slab single-shot turbo spin echo (ssTSE BH) projections were obtained, and these were used for CBD and portal vein diameter (PVD) measurement by workstation software. Initial recruitment included 265 patients, of which 66 were excluded due to abnormal liver function tests, seven more were excluded due to excess imaging artifacts or incomplete CBD visualization, and five were excluded due to other abnormal blood tests. This yielded a final study group of 187 patients between the ages of 21 and 78 years, which comprised 69 women and 118 men. ResultsThe mean CBD diameter is 4.6 mm, with a range from 1.76 to 10.49 mm. CBD diameters are significantly different in patients both younger and older than 65 years of age (p < 0.05), and are not significantly related to gender, serum glucose level, cholesterol level, hepatitis status and PVD. ConclusionOur study showed that the average CBD diameter for an asymptomatic Taiwanese adult is 4.6 mm, with an upper limit of 10.49 mm. CBD diameter is only significantly correlated with age. This is a useful reference in today's clinical setting where MRCP are commonly performed for evaluation of suspected biliary tract disease.

Analysis of perfusion defects by causes other than acute pulmonary thromboembolism on contrast-enhanced dual-energy CT in consecutive 537 patients

To assess causes, incidence and patterns of perfusion defects (PDs) on dual-energy perfusion CT angiography (DECTA) in clinically suspected acute pulmonary thromboembolisms (PTE). Consecutive 537 patients who underwent DECTA for suspicion of PTE were retrospectively reviewed. After excluding patients with possible PTE or unsatisfactory perfusion map quality, 299 patients with 1697 lobes were included. The DECTA (Somatom Definition, Siemens) was performed at 140kV and 80kV. Color-coded perfusion images were obtained with a lung PBV application of the workstation software (Syngo Dual Energy). The presence, incidence, three patterns of PDs (wedge-shaped, heterogeneous, and regionally homogeneous), pulmonary diseases, and the matchedness between the PD and the disease extent were studied. 315 of 1697 lobes (18.6%) in 156 of 299 patients (81.3%) showed PDs. Among them, 51 (3%), 257 (15.1%), and 7 (0.4%) lobes had PDs due to vascular, nonvascular, and unidentifiable causes, respectively. Vascular causes include: pulmonary arterial (PA) hypertension (0.7%), extrinsic occlusion of PA by fibrosis (0.6%), PA hypoplasia (0.6%), vasculitis (0.5%), cancer mass compressing PA, venous occlusion, AVM, and pulmonary angiosarcoma. Most of PDs were wedge-shaped and well-matched. Nonvascular causes include: mosaic attenuation (4.1%), emphysema (3.2%), interstitial fibrosis (1.6%), bronchitis (1.4%), GGO (1.2%), cellular bronchiolitis (1%), bronchiectasis, airway obstruction, compensaroty lung hyperinflation, air trapping, cor-pulmonale, bronchopneumonia, physiologic decreased ventilation, and segmental bronchial atresia. Most of PDs showed heterogeneous pattern and were not matched. Various vascular and nonvascular diseases cause PDs on DECTA. Each disease shows different pattern of PD depending on pathophysiology and physiologic compensation.

Integration of a Robotic Endoscope Holder with the Surgical Assistant Workstation Software Framework

We have integrated the Philips Research robot arm with the Johns Hopkins cisst library, an open-source platform for computer assisted surgical intervention, for assistance during minimally invasive cardiac surgery using image-based steering of an endoscope. The development of a Matlab to C++ wrapper to abstract away servo-level details facilitates the rapid development of a component-based framework with “plug and play” features. This allows the user to easily exchange the robot with an alternative manipulator while maintaining the same overall functionality.

Performance evaluation of MapReduce using full virtualisation on a departmental cloud

Performance evaluation of MapReduce using full virtualisation on a departmental cloudThis work analyses the performance of Hadoop, an implementation of the MapReduce programming model for distributed parallel computing, executing on a virtualisation environment comprised of 1+16 nodes running the VMWare workstation software. A set of experiments using the standard Hadoop benchmarks has been designed in order to determine whether or not significant reductions in the execution time of computations are experienced when using Hadoop on this virtualisation platform on a departmental cloud. Our findings indicate that a significant decrease in computing times is observed under these conditions. They also highlight how overheads and virtualisation in a distributed environment hinder the possibility of achieving the maximum (peak) performance.

Virtual Intraaortic Endoscopy in Severe Calcific Aortic Stenosis

A 93-year-old woman with calcific aortic stenosis who required long-term hemodialysis was referred to our department because of hypotension during hemodialysis. Her echocardiogram showed severe calcific aortic stenosis and concentric left ventricular hypertrophy. Before and after hemodialysis, the left ventricular dimensions changed, and a peak pressure gradient varied from 92 to 53 mm Hg. The morphologic evaluation of the aortic valve was not reliable because of a poor acoustic window. At cardiac catheterization, the valve was not crossed with a catheter. Virtual intraaortic endoscopy was reconstructed from a cardiac electrocardiogram-gated 64-slice computed tomography image (Aquilion 64, Toshiba Medical Systems Corp, Tochigi-ken, Japan). Using the Ziostation 3-dimensional workstation software (Ziosoft Inc, Tokyo, Japan), the movement of the aortic valve could be demonstrated dynamically in all phases of the cardiac cycle, similar to a real intraaortic endoscopic image (Fig 1A; end diastole, 1B; end systole; LCO = left coronary ostium; RCO = right coronary ostium). The cusps were immobilized during systole by the calcific deposits along their flexion lines at their bases. Only the free borders of the cusps were mobilized (Fig 1B). Measurement of the aortic valve area showed it was 0.8 cm2 (Fig 2; LCO = left coronary ostium; RCO = right coronary ostium).Fig 2View Large Image Figure ViewerDownload (PPT) The patient underwent aortic valve replacement with a 17-mm Regent valve (St. Jude Medical, St. Paul, MN). Intraoperative findings confirmed the preoperative virtual endoscopic findings. The patient's postoperative course was uneventful. As the population continues to age, a greater number of patients with senile calcific aortic stenosis will become candidates for aortic valve replacement. We suggest that virtual intraaortic endoscopy might be an alternative diagnostic method to Doppler imaging and catheterization, particularly in patients with severe calcific aortic stenosis.