scholarly journals Behavior of Generated Gas during Femtosecond Laser Lens Irradiation in Porcine Cadaver Eyes

2021 ◽  
Vol 11 (17) ◽  
pp. 8247
Author(s):  
Yoichiro Masuda ◽  
Kotaro Oki ◽  
Akira Watanabe ◽  
Makiko Ohkido ◽  
Hisaharu Iwaki ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Anterior Chamber Depth ◽  
Lens Capsule ◽  
Posterior Capsule ◽  
Irradiation Site ◽  
Irradiation Energy ◽  
Before And After ◽  
Capsular Block Syndrome

(1) Background: We investigated the behavior of gas inside a lens and its influence on the lens capsule, which may cause complications by lens irradiation with a femtosecond laser cataract surgery device. (2) Methods: The crystalline lenses of 6-month-old porcine cadaver eyes were observed during laser irradiation. An intraocular endoscope in the vitreous cavity was used to measure the posterior capsule position. Optical coherence tomography measurements of the anterior chamber depth before and after the laser irradiation, as well as measurements of the equatorial perimeter of the extracted lens, were compared with those of the controls. (3) Results: Femtosecond laser-generated gas in the porcine lens was dependent on laser irradiation energy. Increases in the amount of laser irradiation energy caused the generated gas to coalesce, move backwards beyond the laser irradiation site, and expand the lens capsule and posterior capsule. (4) Conclusions: The present results suggest that laser irradiation-induced gas moves in the direction of the posterior capsule beyond the lens irradiation site and expands the lens capsule, which may be involved in the development of capsular block syndrome.

scholarly journals Outcome of Surgical Treatment in Late-Onset Capsular Block Syndrome

2017 ◽  
Vol 2017 ◽  
pp. 1-8 ◽  
Author(s):  
Yang Huang ◽  
Zi Ye ◽  
Hang Li ◽  
Zhaohui Li
Keyword(s):  
Surgical Treatment ◽  
Inflammatory Cytokines ◽  
Aqueous Humor ◽  
Late Onset ◽  
Anterior Chamber Depth ◽  
Human Lens ◽  
Necrosis Factor Alpha ◽  
Before And After ◽  
Factor Alpha ◽  
Capsular Block Syndrome

Purpose. To further investigate the pathogenesis of late-onset capsular block syndrome (CBS) and to evaluate the safety of surgical treatment.Methods. Seven patients diagnosed with late-onset CBS were retrospectively analyzed. Anterior chamber depth (ACD), intraocular pressure (IOP), refractive diopter, and best-corrected visual acuity (BCVA) before and after surgery were recorded. The opaque substance was tested with Western blot, and a flow cytometer multiple array assay system was utilized to evaluate the levels of inflammatory cytokines from opaque substance and aqueous humor, respectively.Results. Patients who had undergone surgical treatment showed a significant BCVA and spherical equivalent refractive error improvement (P=0.002,P=0.021, resp.). Nevertheless, ACD and IOP before and after surgery were in normal range with no difference (P=0.165,P=0.749, resp.).αB-crystallin andβB-crystallin were detected in all opaque substances. Tumor necrosis factor-alpha (TNF-α) and interlukin-1β(IL-1β) levels in opaque substance were significantly higher than those in aqueous humor (P=0.038,P=0.007, resp.), while IL-2 and IL-6 were not detected in any samples.Conclusions. Opaque substance is derived from human lens epithelial cells. Inflammatory cytokines may be involved in the pathogenesis of late-onset CBS. In addition, surgical treatment is an effective approach. This trial is registered withChiCTR-IOR-17011287.

scholarly journals Study of State of Interface “Intraocular Lens — Posterior Capsule” Depending on Size of Capsulorhexis in Senile Cataract Phacoemulsification

2021 ◽  
Vol 18 (3) ◽  
pp. 427-432
Author(s):  
Lina Bai ◽  
O. V. Kolenko ◽  
A. V. Egorova ◽  
A. V. Vasiliev
Keyword(s):  
Optical Coherence Tomography ◽  
Femtosecond Laser ◽  
Intraocular Lens ◽  
Senile Cataract ◽  
Posterior Capsule ◽  
Average Depth ◽  
Maximum Value ◽  
Full Contact ◽  
Corneal Opacities ◽  
Capsular Bag

Purpose. To study the state of interface “intraocular lens (IOL) — posterior capsule (PC)” depending on diameter of capsulorhexis in phacoemulsification of senile cataract.Patients and methods. 227 patients (227 eyes) were examined after phacoemulsification of senile cataract at LenSx femtosecond laser (Alcon, USA). The study did not include patients with corneal opacities, signs of axial displacement of lens, with irido- and phacodonesis, glaucoma, axial length less than 22 mm and more than 26 mm. Depending on diameter of performed capsulorhexis, we formed 3 groups: 1st group — 76 eyes with diameter capsulorexis 5.5 mm; 2nd group — 73 eyes with 5.0 mm; 3rd group — 78 eyes with 4.5 mm. We studied type of interface “IOL — PC”, the maximum value of PC diastasis and the maximum depth of its folds using an RTVue-100 Optical Coherence Tomography (Optovue, USA) on the first day after the operation.Results. The maximum number of eyes with absence of contact between IOL and PC was noted in the 3rd group (62.8 %), the largest number of eyes with full contact between IOL and PC (63.2 %) was in the 1st group. The minimum average depth of the PC folds (111.1 ± 32.7 μm) was noted in the 1st group, and the maximum (165 ± 75.4 μm) — in the 2nd group.Conclusion. The analysis showed that type of interface “IOL — PC” in the first day after phacoemulsification of senile cataract depends on diameter of capsulorhexis. The largest number of eyes (64.6 %) with full contact between IOL and PC was observed in the group of patients with capsulorhexis 5.5 mm, and the smallest (6.4 %) — in eyes with diameter capsulorexis 4.5 mm. Presumably, the main reason for the absence or incomplete contact between IOL and PC is the presence of viscous dispersive between them. The deformation of PC in the form of folds does not directly depend on diameter of capsulorhexis and, obviously, is due to the uneven tension of the capsular bag by the IOL haptics.

scholarly journals Coherent phonon dynamics in a c-plane sapphire crystal before and after intense femtosecond laser irradiation

2020 ◽  
Vol 28 (11) ◽  
pp. 16003
Author(s):  
Xin Zhao ◽  
Zhaogang Nie ◽  
Lin Ma ◽  
Fangteng Zhang ◽  
Mingming Hao ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Femtosecond Laser Irradiation ◽  
Sapphire Crystal ◽  
Coherent Phonon ◽  
Phonon Dynamics ◽  
Before And After

Generation of nano-bumps on transparent quartz glass surface under femtosecond laser irradiation

2008 ◽  
Author(s):  
Wei Guo ◽  
Zeng Bo Wang ◽  
Lin Li ◽  
Zhu Liu ◽  
Boris Luk’yanchuk ◽  
...  
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Quartz Glass ◽  
Glass Surface ◽  
Femtosecond Laser Irradiation

scholarly journals Utilization potential of intraluminal optical coherence tomography for the Eustachian tube

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hayoung Byun ◽  
Yeon Hoon Kim ◽  
Jingchao Xing ◽  
Su-Jin Shin ◽  
Seung Hwan Lee ◽  
...  
Keyword(s):  
Optical Coherence Tomography ◽  
Eustachian Tube ◽  
Balloon Dilatation ◽  
Optical Coherence ◽  
Cross Sectional ◽  
Anatomical Structures ◽  
Complex Anatomy ◽  
Before And After ◽  
Tubal Lumen ◽  
Oct Image

AbstractImaging the Eustachian tube is challenging because of its complex anatomy and limited accessibility. This study fabricated a fiber-based optical coherence tomography (OCT) catheter and investigated its potential for assessing the Eustachian tube anatomy. A customized OCT system and an imaging catheter, termed the Eustachian OCT, were developed for visualizing the Eustachian tube. Three male swine cadaver heads were used to study OCT image acquisition and for subsequent histologic correlation. The imaging catheter was introduced through the nasopharyngeal opening and reached toward the middle ear. The OCT images were acquired from the superior to the nasopharyngeal opening before and after Eustachian tube balloon dilatation. The histological anatomy of the Eustachian tube was compared with corresponding OCT images, The new, Eustachian OCT catheter was successfully inserted in the tubal lumen without damage. Cross-sectional images of the tube were successfully obtained, and the margins of the anatomical structures including cartilage, mucosa lining, and fat could be successfully delineated. After balloon dilatation, the expansion of the cross-sectional area could be identified from the OCT images. Using the OCT technique to assess the Eustachian tube anatomy was shown to be feasible, and the fabricated OCT image catheter was determined to be suitable for Eustachian tube assessment.

scholarly journals Subtle changes of the crystalline lens after cycloplegia: a retrospective study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Cheng Dai ◽  
Meng Liu ◽  
Xiaodong Lv ◽  
Binzhong Li
Keyword(s):  
Retrospective Study ◽  
Children And Adolescents ◽  
Population Change ◽  
Anterior Segment ◽  
Anterior Chamber Depth ◽  
Crystalline Lens ◽  
Equivalent Diameter ◽  
Crystalline Morphology ◽  
Significant Difference ◽  
Before And After

Abstract Background The purpose of this study was to evaluate the shape of the crystalline lens in terms of biometry and diopters before and after cycloplegia using the CASIA2 swept-source (SS) optical coherence tomography (OCT) system on the anterior segment. Methods This was a retrospective study. Children and adolescents (26 males and 29 females, aged 4–21 years) with simple ametropia were selected for optometry and CASIA2 imaging at 2 separate visits before and after cycloplegia. Diopter values were derived from the spherical power (S) obtained by optometry. Biometric parameters of the crystalline lens, including the anterior chamber depth (ACD), anterior and posterior curvature of the lens (ACL and PCL), lens thickness (LTH), lens decentration (LD), lens tilt (LT), and equivalent diameter of the lens (LED), were measured by the CASIA2 system. The differences in these parameters after compared with before cycloplegia were determined, and their relationships were analyzed. Results Fifty-five participants (106 eyes) were initially enrolled. There was a significant difference (P < 0.05) in the S (t=-7.026, P < 0.001), ACD (t=-8.796, P < 0.001), ACL (t=-13.263, P < 0.001) and LTH (t = 7.363, P < 0.001) after compared with before cycloplegia. The change in the PCL (t = 1.557, P = 0.122), LD (t = 0.876, P = 0.383), LT (t = 0.440, P = 0.661) and LED (t=-0.351, P = 0.726) was not statistically significant (P > 0.05). There was a significant (P < 0.05) correlation of the change in the S with that in the ACL (r = 0.466, P < 0.001), LTH (r=-0.592, P < 0.001), and LED (r = 0.223, P = 0.021) but not the PCL (r = 0.19, P = 0.051), LD (r=-0.048, P = 0.0628) or LT (r=-0.022, P = 0.822). Furthermore, the change in the ACD was closely related to the change in crystalline morphology. However, in children and adolescents, we found that the change in crystalline morphology was unrelated to age. Conclusions Changes in lens morphology after compared with before cycloplegia are mainly related to the ACL and LTH, but there is no difference in the PCL, LD, LT, or LED. In the adolescent population, change in the S is related to change in the ACL, LED and LTH. However, age is unrelated to the shape and tendency of the crystalline lens. Further research is required to determine whether the same conclusion applies to different age groups and different refractive states (myopia, hyperopia, emmetropia) .

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