Pulmonary Vascular Tree Segmentation from Contrast-Enhanced CT Images

We present a pulmonary vessel segmentation algorithm, which is fast, fully automatic and robust. It uses a coarse segmentation of the airway tree and a left and right lung labeled volume to restrict a vessel enhancement filter, based on an offset medialness function, to the lungs. We show the application of our algorithm on contrast-enhanced CT images, where we derive a clinical parameter to detect pulmonary hypertension (PH) in patients. Results on a dataset of 24 patients show that quantitative indices derived from the segmentation are applicable to distinguish patients with and without PH. Further work-in-progress results are shown on the VESSEL12 challenge dataset, which is composed of non-contrast-enhanced scans, where we range in the midfield of participating contestants.Comment: Part of the OAGM/AAPR 2013 proceedings (1304.1876

Healthy Lung Vessel Morphology Derived From Thoracic Computed Tomography

Knowledge of the lung vessel morphology in healthy subjects is necessary to improve our understanding about the functional network of the lung and to recognize pathologic deviations beyond the normal inter-subject variation. Established values of normal lung morphology have been derived from necropsy material of only very few subjects. In order to determine morphologic readouts from a large number of healthy subjects, computed tomography pulmonary angiography (CTPA) datasets, negative for pulmonary embolism, and other thoracic pathologies, were analyzed using a fully-automatic, in-house developed artery/vein separation algorithm. The number, volume, and tortuosity of the vessels in a diameter range between 2 and 10mm were determined. Visual inspection of all datasets was used to exclude subjects with poor image quality or inadequate artery/vein separation from the analysis. Validation of the algorithm was performed manually by a radiologist on randomly selected subjects. In 123 subjects (men/women: 55/68), aged 59 +/- 17 years, the median overlap between visual inspection and fully-automatic segmentation was 94.6% (69.2-99.9%). The median number of vessel segments in the ranges of 8-10, 6-8, 4-6, and 2-4 mm diameter was 9, 34, 134, and 797, respectively. Number of vessel segments divided by the subject's lung volume was 206 vessels/L with arteries and veins contributing almost equally. In women this vessel density was about 15% higher than in men. Median arterial and venous volumes were 1.52 and 1.54% of the lung volume, respectively. Tortuosity was best described with the sum-of-angles metric and was 142.1 rad/m (138.3-144.5 rad/m). In conclusion, our fully-automatic artery/vein separation algorithm provided reliable measures of pulmonary arteries and veins with respect to age and gender. There was a large variation between subjects in all readouts. No relevant dependence on age, gender, or vessel type was observed. These data may provide reference values for morphometric analysis of lung vessels

The role of pulmonary arterial stiffness in COPD

AbstractCOPD is the second most common cause of pulmonary hypertension, and is a common complication of severe COPD with significant implications for both quality of life and mortality. However, the use of a rigid diagnostic threshold of a mean pulmonary arterial pressure (mPAP) of ≥25mHg when considering the impact of the pulmonary vasculature on symptoms and disease is misleading. Even minimal exertion causes oxygen desaturation and elevations in mPAP, with right ventricular hypertrophy and dilatation present in patients with mild to moderate COPD with pressures below the threshold for diagnosis of pulmonary hypertension. This has significant implications, with right ventricular dysfunction associated with poorer exercise capability and increased mortality independent of pulmonary function tests.The compliance of the pulmonary artery (PA) is a key component in decoupling the right ventricle from the pulmonary bed, allowing the right ventricle to work at maximum efficiency and protecting the microcirculation from large pressure gradients. PA stiffness increases with the severity of COPD, and correlates well with the presence of exercise induced pulmonary hypertension. A curvilinear relationship exists between PA distensibility and mPAP and pulmonary vascular resistance (PVR) with marked loss of distensibility before a rapid rise in mPAP and PVR occurs with resultant right ventricular failure. This combination of features suggests PA stiffness as a promising biomarker for early detection of pulmonary vascular disease, and to play a role in right ventricular failure in COPD. Early detection would open this up as a potential therapeutic target before end stage arterial remodelling occurs

Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study

The VESSEL12 (VESsel SEgmentation in the Lung) challenge objectively compares the performance of different algorithms to identify vessels in thoracic computed tomography (CT) scans. Vessel segmentation is fundamental in computer aided processing of data generated by 3D imaging modalities. As manual vessel segmentation is prohibitively time consuming, any real world application requires some form of automation. Several approaches exist for automated vessel segmentation, but judging their relative merits is difficult due to a lack of standardized evaluation. We present an annotated reference dataset containing 20 CT scans and propose nine categories to perform a comprehensive evaluation of vessel segmentation algorithms from both academia and industry. Twenty algorithms participated in the VESSEL12 challenge, held at International Symposium on Biomedical Imaging (ISBI) 2012. All results have been published at the VESSEL12 website http://vessel12.grand-challenge.org. The challenge remains ongoing and open to new participants. Our three contributions are: (1) an annotated reference dataset available online for evaluation of new algorithms; (2) a quantitative scoring system for objective comparison of algorithms; and (3) performance analysis of the strengths and weaknesses of the various vessel segmentation methods in the presence of various lung diseases.Rudyanto, RD.; Kerkstra, S.; Van Rikxoort, EM.; Fetita, C.; Brillet, P.; Lefevre, C.; Xue, W.... (2014). Comparing algorithms for automated vessel segmentation in computed tomography scans of the lung: the VESSEL12 study. Medical Image Analysis. 18(7):1217-1232. doi:10.1016/j.media.2014.07.003S1217123218

Friedrich Mayer-Beck : Leben und druckgraphisches Werk

Die vorliegende Diplomarbeit befasst sich mit dem Leben des Künstlers Friedrich Mayer-Beck (1907 Wien - 1977 Leoben) und seinem umfangreichen druckgraphischen Werk, das bisher in der Literatur noch nicht ausführlich bearbeitet wurde.Die Arbeit ist nach Lebensabschnitten gegliedert, welche die Jugend- und Ausbildungszeit, die Zeit seiner Tätigkeit in Graz vor und im 2. Weltkrieg, seine schwierige Lage nach dem 2. Weltkrieg und die Neupositionierung in Leoben, seine umfangreiche Tätigkeit bis zur Pensionierung und schließlich die wenigen Jahre bis zu seinem Tod umfassen.Mayer-Beck erhielt in den Jahren 1925 bis 1929 eine fundierte Ausbildung an der Akademie der bildenden Künste in Wien, wo er anschließend bis 1933 auch die Meisterklasse bei Prof. Rudolf Bacher besuchte. Nach seiner Ausbildung war er zuerst in Wien, dann in Graz und in Leoben an verschiedenen Gymnasien als Lehrer tätig, zuletzt am heutigen BG/BRG Leoben 1.Der Schwerpunkt seiner künstlerischen Arbeit lag bis zum Ende des 2. Weltkrieges auf der Arbeit mit Holzstichen im Stil der Neuen Sachlichkeit und der Buchillustration. Eine Liste der illustrierten Bücher ist im Anhang enthalten.Nach dem Krieg wendet sich der Künstler dem Holzschnitt und der Hinterglasmalerei zu. Seine Themen sind die zutiefst menschlichen Grundfragen nach dem Sinn des Lebens, Schmerz, Leid und Tod. Inhaltlich greift er dabei vorwiegend auf die Bibel (AT und NT) und auf die Werke der Weltliteratur zurück. Er entwickelt einen eigenständigen, kalligraphisch geprägten, expressiven Stil.Seine Arbeiten im Holzschnitt sind mit Werken von Hans Fronius, Switbert Lobisser und Franz Weiß vergleichbar und erreichen ein ebenbürtiges Niveau. Graphische Arbeiten Mayer-Becks wurden von der Albertina in Wien und der Neuen Galerie am Joanneum in Graz angekauft. Leider fanden sie ansonsten nur in einem kleinen Kreis von Liebhabern Verbreitung und drohen nun in Vergessenheit zu geraten. Dem soll diese Diplomarbeit entgegenwirken.The following paper is about the life of the artist Friedrich Mayer-Beck (1907 in Vienna - 1977 in Leoben) an his extensive graphich work, which has not been thoroughly compiled an edited so far.The structure of the text follows the important periods of his life, covering his youth and education, his time in Graz before and during World War II, his difficult position after the Great War, re-positioning in Leoben, his extensive work until retirement an finally the the few productive years until his death.Mayer-Beck received a sound education at the Academy of Fine Arts in Vienna from 1925 to 1929, where he subsequently visited the master class of Prof. Rudolf Bacher until 1933. After his education he was working as a teacher at several grammar schools (in Austria: Gymnasium), first in Vienna, then in Graz an finally in Leoben.The focus of his artistic work until the end of World War II is on wood-engravings in the style of the "Neue Sachlichkeit" ("new objectivity") as well as book illustrations (a list of these books is included in the appendix).After the war the artist turned his attention toward wood-cuts an reverse glass paintings (in German: "Hinterglasbilder"). His topics are basic questions of the human existence: the meaning of life, pain, suffering and death. He received his inspiration from the bible (Old an New Testament) an works of the world literature, an he developed an individual, calligraphically affected, expressive style.His wood-cuts are comparable and on par to those by Hans Fronius, Switbert Lobisser and Franz Weiß. Graphical works by Mayer-Beck were acquired by the Albertina in Vienna and the Neue Galerie am Universalmuseum Joanneum in Graz. Unfortunately they did not reach attention beyond a small circle of aficionados and went largely unnoticed by the larger public, an are therefore faced to sink to oblivion, which this paper tries to prevent.Abweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in dt. u. engl. SpracheGraz, Univ., Dipl.-Arb., 2013(VLID)23207

Reading pulmonary vascular pressure tracings: How to handle the problems of zero leveling and respiratory swings

The accuracy of pulmonary vascular pressure measurements is of great diagnostic and prognostic relevance. However, there is variability of zero leveling procedures, and the current recommendation of end-expiratory reading may not always be adequate. A review of physiological and anatomical data, supported by recent imaging, leads to the practical recommendation of zero leveling at the cross-section of three transthoracic planes, which are, respectively midchest frontal, transverse through the fourth intercostal space, and midsagittal. As for the inevitable respiratory pressure swings, end-expiratory reading at functional residual capacity allows for minimal influence of elastic lung recoil on pulmonary pressure reading. However, hyperventilation is associated with changes in end-expiratory lung volume and increased intrathoracic pressure, eventually exacerbated by expiratory muscle contraction and dynamic hyperinflation, all increasing pulmonary vascular pressures. This problem is amplified in patients with obstructed airways. With the exception of dynamic hyperinflation states, it is reasonable to assume that negative inspiratory and positive expiratory intrathoracic pressures cancel each other out, so averaging pulmonary vascular pressures over several respiratory cycles is most often preferable. This recommendation may be generalized for the purpose of consistency and makes sense, as pulmonary blood flow measurements are not corrected for phasic inspiratory and expiratory changes in clinical practice.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Celebrating Our Histories: Institutional Anniversaries in Archives and Special Collections

Archives and special collections actively work to preserve the institutional memory of the organizations or communities they represent. This makes these repositories the perfect resources for commemorating institutional anniversaries and other historic milestones. The purpose of this panel is to discuss how four Florida archives and special collections recently celebrated these notable dates. The presenters will discuss how they commemorated their special occasions through exhibitions, events, and more. Each group will give insights into their efforts and share takeaways from their experiences. Alexandra Vargas-Minor from Ringling College of Art & Design will discuss how the Ringling College Archives commemorated the College’s 90th anniversary through the creation of the inaugural archives exhibition titled 90 Years in the Ringling College Archives in the Spring of 2022. Alexandra will discuss her experience creating an exhibition spanning a 90-year history, tailoring archival programming and events to different audiences, and creating a digital timeline to succeed the exhibition. Rochelle Pienn and Emily Calderon from the Broward County Libraries will discuss how the African American Research Library and Cultural Center (AARLCC) is celebrating its 20th anniversary in 2022 with year-long programming. AARLCC kicked off the Vicennial of Black Excellence on February 11, 2022 with an opening exhibition Collector’s Duet: The Lifelong Librarianship of Vivian D. Hewitt and Dorothy Porter Wesley and reception. Broward County Library Special Collections staff will share their experiences and lessons learned from preparing the exhibit and virtual program. Jeffrey Zines from Florida International University will discuss how the University Archives and Special Collections department is participating in celebrating FIU’s 50th anniversary this fall. The FIU in ’72 celebration includes a curated display of photos and ephemera commemorating notable events in the university’s early years, which is located in the Green Library gallery. Jeffrey will also discuss responding to requests from other departments across campus who wish to develop their own commemorative displays. Victoria Jones from Florida Gulf Coast University will discuss how the University Archives and Special Collections has celebrated FGCU’s silver anniversary this fall. Recognizing that student involvement has been key to the university\u27s growth and development, the University Archives and Special Collections showcased campus life in their exhibition, Wings Up: 25 Years of Student Life at FGCU. Victoria will share lessons learned from the creation of the exhibition, programming, and the exhibit’s impact on collection development