Visualization of photothermal interaction of Bessel beam with gastric tumor based on COMSOL

2021 ◽  
Author(s):  
Ao Teng ◽  
Xianlin Song
Keyword(s):  
Bessel Beam ◽  
Gastric Tumor

Giant Solitary Gastric Peutz-Jeghers Polyp Mimicking a Malignant Gastric Tumor: the Largest Described in Literature

2014 ◽  
Vol 23 (3) ◽  
pp. 321-324 ◽  
Author(s):  
Sorinel Lunca ◽  
Vlad Porumb ◽  
Natalia Velenciuc ◽  
Dan Ferariu ◽  
Gabriel Dimofte
Keyword(s):  
Upper Gastrointestinal Bleeding ◽  
Rare Event ◽  
Gastric Tumor ◽  
Node Metastasis ◽  
Mucocutaneous Pigmentation ◽  
History Of ◽  
Peutz Jeghers Syndrome ◽  
Upper Gastrointestinal ◽  
Gastric Malignancy ◽  
Polypoid Tumor

A solitary Peutz-Jeghers polyp is defined as a unique polyp occurring without associated mucocutaneous pigmentation or a family history of Peutz-Jeghers syndrome. Gastric solitary localization is a rare event, with only eight reported cases to date. We report herein the case of a 43-year old woman who presented with upper gastrointestinal bleeding, severe anemia, weight loss and asthenia. Endoscopy revealed a giant polypoid tumor with signs of neoplastic invasion of the cardia, with pathological aspect suggesting a Peutz-Jeghers hamartomatous polyp. Computed tomography suggested a malignant gastric tumor and a total gastrectomy was performed. The pathological specimen showed a giant 150/70/50 mm polypoid tumor and immunochemistry established the final diagnostic of a Peutz-Jegers type polyp. This is the largest solitary Peutz-Jeghers gastric polyp reported until now, and the second one mimicking a gastric malignancy with lymph node metastasis.

scholarly journals Photonic nanojet generated by a spheroidal particle illuminated by a vector Bessel beam

2021 ◽  
pp. 100106
Author(s):  
Yongjie Jia ◽  
Renxian Li ◽  
Wenze Zhuang ◽  
Jiarui Liang
Keyword(s):  
Bessel Beam ◽  
Spheroidal Particle ◽  
Photonic Nanojet

scholarly journals “Perfect” Terahertz Vortex Beams Formed Using Diffractive Axicons and Prospects for Excitation of Vortex Surface Plasmon Polaritons

2021 ◽  
Vol 11 (2) ◽  
pp. 717
Author(s):  
Boris Knyazev ◽  
Valery Cherkassky ◽  
Oleg Kameshkov
Keyword(s):  
Surface Plasmon ◽  
Surface Plasmon Polaritons ◽  
Bessel Beam ◽  
Diffraction Theory ◽  
Terahertz Range ◽  
High Resistivity ◽  
Visible Range ◽  
Optical Elements ◽  
Scalar Diffraction ◽  
Plasmon Polaritons

Transformation of a Bessel beam by a lens results in the formation of a “perfect” vortex beam (PVB) in the focal plane of the lens. The PVB has a single-ring cross-section and carries an orbital angular momentum (OAM) equal to the OAM of the “parent” beam. PVBs have numerous applications based on the assumption of their ideal ring-type structure. For instance, we proposed using terahertz PVBs to excite vortex surface plasmon polaritons propagating along cylindrical conductors and the creation of plasmon multiplex communication lines in the future (Comput. Opt. 2019, 43, 992). Recently, we demonstrated the formation of PVBs in the terahertz range using a Bessel beam produced using a spiral binary silicon axicon (Phys. Rev. A 2017, 96, 023846). It was shown that, in that case, the PVB was not annular, but was split into nested spiral segments, which was obviously a consequence of the method of Bessel beam generation. The search for methods of producing perfect beams with characteristics approaching theoretically possible ones is a topical task. Since for the terahertz range, there are no devices like spatial modulators of light in the visible range, the main method for controlling the mode composition of beams is the use of diffractive optical elements. In this work, we investigated the characteristics of perfect beams, the parent beams being quasi-Bessel beams created by three types of diffractive phase axicons made of high-resistivity silicon: binary, kinoform, and “holographic”. The amplitude-phase distributions of the field in real perfect beams were calculated numerically in the approximation of the scalar diffraction theory. An analytical expression was obtained for the case of the binary axicon. It was shown that a distribution closest to an ideal vortex was obtained using a holographic axicon. The resulting distributions were compared with experimental and theoretical distributions of the evanescent field of a plasmon near the gold–zinc sulfide–air surface at different thicknesses of the dielectric layer, and recommendations for experiments were given.

Non-diffraction-length Bessel-beam femtosecond laser drilling of high-aspect-ratio microholes in PMMA

Optik ◽  
2021 ◽  
Vol 229 ◽  
pp. 166295
Author(s):  
Haoran Wang ◽  
Fan Zhang ◽  
Kaiwen Ding ◽  
Ji'an Duan
Keyword(s):  
Aspect Ratio ◽  
Femtosecond Laser ◽  
High Aspect Ratio ◽  
Bessel Beam ◽  
Laser Drilling

scholarly journals Effective use of the “clip-flap” method for the endoscopic submucosal dissection of a difficult-to-approach superficial gastric tumor

Endoscopy ◽  
2015 ◽  
Vol 47 (S 01) ◽  
pp. E318-E319 ◽  
Author(s):  
Katsumi Yamamoto ◽  
Shiro Hayashi ◽  
Tsutomu Nishida ◽  
Hirotsugu Saiki ◽  
Masafumi Naito ◽  
...  
Keyword(s):  
Endoscopic Submucosal Dissection ◽  
Gastric Tumor ◽  
Submucosal Dissection ◽  
Effective Use

scholarly journals Pulmonary calcified masses and gastric tumor: Incomplete Carney's triad

2017 ◽  
Vol 23 (6) ◽  
pp. 372-373
Author(s):  
B. Hochhegger ◽  
S. Camargo ◽  
E. Marchiori
Keyword(s):  
Gastric Tumor ◽  
Carney’S Triad

Ultrahigh resolution optical coherence elastography using a Bessel beam for extended depth of field

2016 ◽  
Author(s):  
Andrea Curatolo ◽  
Martin Villiger ◽  
Dirk Lorenser ◽  
Philip Wijesinghe ◽  
Alexander Fritz ◽  
...  
Keyword(s):  
Bessel Beam ◽  
Depth Of Field ◽  
Optical Coherence ◽  
Ultrahigh Resolution ◽  
Extended Depth Of Field
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