Three-dimensional ion imaging study of PCl3 photodissociation at 235 nm

Abstract Background The imaging characteristics of sacral sacralalar-iliac (S2AI) screw trajectory in adult degenerative scoliosis (ADS) patients will be determined. Methods S2AI screw trajectories were mapped on three-dimensional computed tomography (3DCT) reconstructions of 40 ADS patients. The starting point, placement plane, screw template, and a circle centered at the lowest point of the ilium inner cortex were set on these images. A tangent line from the starting point to the outer diameter of the circle was selected as the axis of the screw trajectory. The related parameters in different populations were analyzed and compared. Results The trajectory length of S2AI screws in ADS patients was 12.00 ± 0.99 cm, the lateral angle was 41.24 ± 3.92°, the caudal angle was 27.73 ± 6.45°, the distance from the axis of the screw trajectory to the iliosciatic notch was 1.05 ± 0.81 cm, the distance from the axis of the screw trajectory to the upper edge of the acetabulum was 1.85 ± 0.33 cm, and the iliac width was 2.12 ± 1.65 cm. Compared with females, the lateral angle of male ADS patients was decreased, but the trajectory length was increased (P < 0.05). Compared to patients without ADS in previous studies, the lateral angle of male patients was larger, the lateral angle of female patients was increased, and the caudal angle was decreased (P < 0.05). Conclusions There is an ideal trajectory of S2AI screws in ADS patients. A different direction should be noticed in the placement of S2AI screws, especially in female patients.

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Ultraviolet photodissociation dynamics of PCl3 at 235 nm: three-dimensional ion imaging and theoretical analysis

Physical Chemistry Chemical Physics ◽

10.1039/d1cp01396c ◽

2021 ◽

Author(s):

Alexei Chichinin ◽

Christof Maul ◽

Karl-Heinz Gericke

Keyword(s):

Theoretical Analysis ◽

Ground State ◽

Multiphoton Ionization ◽

Three Dimensional ◽

Ion Imaging ◽

Ultraviolet Photodissociation

The photodissociation dynamics of PCl3 at 235 nm has been studied by monitoring ground state Cl(2P3/2) and spin-orbitally excited Cl(2P1/2) atoms by resonance enhanced multiphoton ionization(REMPI). Also, the PCl+n (n=0,1,2)...

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Three-dimensional (3D) velocity map imaging: from technique to application

Journal of Physics B Atomic Molecular and Optical Physics ◽

10.1088/1361-6455/ac4b42 ◽

2022 ◽

Author(s):

Gihan Basnayake ◽

Yasashri Ranathunga ◽

Suk Kyoung Lee ◽

Wen Li

Keyword(s):

Three Dimensional ◽

Cost Effective ◽

Velocity Map Imaging ◽

Imaging Method ◽

Translational Energy ◽

Ion Imaging ◽

Standard Tool ◽

Recent Advancement ◽

Acquisition Speed ◽

Energy And Angular Distributions

Abstract The velocity map imaging (VMI) technique was first introduced by Eppink and Parker in 1997, as an improvement to the original ion imaging method by Houston and Chandler in 1987. The method has gained huge popularity over the past two decades and has become a standard tool for measuring high-resolution translational energy and angular distributions of ions and electrons. VMI has evolved gradually from 2D momentum measurements to 3D measurements with various implementations and configurations. The most recent advancement has brought unprecedented 3D performance to the technique in terms of resolutions (both spatial and temporal), multi-hit capability as well as acquisition speed while maintaining many attractive attributes afforded by conventional VMI such as being simple, cost-effective, visually appealing and versatile. In this tutorial we will discuss many technical aspects of the recent advancement and its application in probing correlated chemical dynamics.

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Photoionization and photodissociation of HCl(BΣ+1,J=0) near 236 and 239nm using three-dimensional ion imaging

The Journal of Chemical Physics ◽

10.1063/1.2198831 ◽

2006 ◽

Vol 124 (22) ◽

pp. 224324 ◽

Cited By ~ 28

Author(s):

A. I. Chichinin ◽

C. Maul ◽

K.-H. Gericke

Keyword(s):

Three Dimensional ◽

Ion Imaging

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Quadratus lumborum block: an imaging study of three approaches

Regional Anesthesia and Pain Medicine ◽

10.1136/rapm-2020-101554 ◽

2020 ◽

Vol 46 (1) ◽

pp. 35-40

Author(s):

Angela Lucia Balocco ◽

Ana M López ◽

Cedric Kesteloot ◽

Jean-Louis Horn ◽

Jean-François Brichant ◽

...

Keyword(s):

Three Dimensional ◽

Imaging Study ◽

Transverse Process ◽

Distribution Patterns ◽

Transversus Abdominis ◽

Paravertebral Space ◽

Posterior Aspect ◽

Quadratus Lumborum ◽

Psoas Muscles ◽

Human Cadavers

Background and objectivesDifferent injection techniques for the quadratus lumborum (QL) block have been described. Data in human cadavers suggest that the transverse oblique paramedian (TOP) QL3 may reach the thoracic paravertebral space more consistently than the QL1 and QL2. However, the distribution of injectate in cadavers may differ from that in patients. Hence, we assessed the distribution of the injectate after the QL1, QL2, and TOP QL3 techniques in patients.Materials and methodsThirty-four patients scheduled for abdominal surgery received QL blocks postoperatively; 26 patients received bilateral and 8 patients received unilateral blocks. Block injections were randomly allocated to QL1, QL2, or TOP QL3 techniques (20 blocks per each technique). The injections consisted of 18 mL of ropivacaine 0.375% with 2 mL of radiopaque contrast, injected lateral or posterior to the QL muscle for the QL1 and QL2 techniques, respectively. For the TOP QL3, the injection was into the plane between the QL and psoas muscles, proximal to the L2 transverse process. Two reviewers, blinded to the allocation, reviewed three-dimensional computed tomography (3D-CT) images to assess the distribution of injectate.Results and discussionThe QL1 block spread in the transversus abdominis plane (TAP), QL2 in the TAP, and posterior aspect of the QL muscle, whereas TOP QL3 spread consistently in the anterior aspect of the QL muscle with occasional spread to the lumbar and thoracic paravertebral areas.ConclusionsThe spread of injectate after QL1, QL2, and QL3 blocks, resulted in different distribution patterns, primarily in the area of injection. The TOP QL3 did not result in consistent interfascial spread toward the thoracic paravertebral space.

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