ABSTRACT
Atraumatic splenic rupture is a rare complication of acute and chronic pancreatitis. It arises due to its anatomical proximity to the pancreas, for instance, due to erosion of large pseudocysts or walled-of-necrosis (WON).Following we describe the case of a 62-year-old woman who presented for further diagnostics and treatment of acute pancreatitis with the development of large walled-of necrosis (WON) in the pancreatic corpus and tail. During the course, the patient developed a hemorrhagic shock. An emergency computer tomography (CT) of the abdomen revealed a ruptured spleen with a large capsular hematoma with no evidence of active bleeding. In contrast to previous published case reports, our treatment was exclusively minimal-invasive: by radiological guided embolization of the splenic artery and by endosonographic guided implantation of a lumen apposing metal stent (LAMS). The splenic hematoma was spontaneously regressive without secondary drainage.
Subject(s)
Pancreatitis, Acute Necrotizing , Shock, Hemorrhagic , Splenic Rupture , Female , Humans , Middle Aged , Pancreatitis, Acute Necrotizing/diagnosis , Pancreatitis, Acute Necrotizing/diagnostic imaging , Shock, Hemorrhagic/diagnosis , Shock, Hemorrhagic/etiology , Shock, Hemorrhagic/therapy , Acute Disease , Stents , Drainage/methods , Splenic Rupture/diagnostic imaging , Splenic Rupture/etiology , Necrosis , Hematoma/diagnosis , Hematoma/diagnostic imaging , Treatment OutcomeABSTRACT
How long does it take to emit an electron from an atom? This question has intrigued scientists for decades. As such emission times are in the attosecond regime, the advent of attosecond metrology using ultrashort and intense lasers has re-triggered strong interest on the topic from an experimental standpoint. Here, we present an approach to measure such emission delays, which does not require attosecond light pulses, and works without the presence of superimposed infrared laser fields. We instead extract the emission delay from the interference pattern generated as the emitted photoelectron is diffracted by the parent ion's potential. Targeting core electrons in CO, we measured a 2d map of photoelectron emission delays in the molecular frame over a wide range of electron energies. The emission times depend drastically on the photoelectrons' emission directions in the molecular frame and exhibit characteristic changes along the shape resonance of the molecule.
ABSTRACT
The photodissociation dynamics of strong-field ionized methyl iodide (CH3I) were probed using intense extreme ultraviolet (XUV) radiation produced by the SPring-8 Angstrom Compact free electron LAser (SACLA). Strong-field ionization and subsequent fragmentation of CH3I was initiated by an intense femtosecond infrared (IR) pulse. The ensuing fragmentation and charge transfer processes following multiple ionization by the XUV pulse at a range of pump-probe delays were followed in a multi-mass ion velocity-map imaging (VMI) experiment. Simultaneous imaging of a wide range of resultant ions allowed for additional insight into the complex dynamics by elucidating correlations between the momenta of different fragment ions using time-resolved recoil-frame covariance imaging analysis. The comprehensive picture of the photodynamics that can be extracted provides promising evidence that the techniques described here could be applied to study ultrafast photochemistry in a range of molecular systems at high count rates using state-of-the-art advanced light sources.
ABSTRACT
Photoionization is one of the fundamental light-matter interaction processes in which the absorption of a photon launches the escape of an electron. The time scale of this process poses many open questions. Experiments have found time delays in the attosecond (10-18 seconds) domain between electron ejection from different orbitals, from different electronic bands, or in different directions. Here, we demonstrate that, across a molecular orbital, the electron is not launched at the same time. Rather, the birth time depends on the travel time of the photon across the molecule, which is 247 zeptoseconds (1 zeptosecond = 10-21 seconds) for the average bond length of molecular hydrogen. Using an electron interferometric technique, we resolve this birth time delay between electron emission from the two centers of the hydrogen molecule.