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1.
BMC Surg ; 24(1): 162, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762739

RESUMO

OBJECTIVES: To compare the efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism (DVT) in lower extremities after total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: A total of 592 patients were enrolled in the study. Clinical data of patients who underwent total hip arthroplasty (THA) and total knee arthroplasty (TKA) in our hospital from December 2021 to September 2022 were retrospectively collected, which mainly included patients' general information, surgery-related information, and DVT-related information. The patients were categorized into the nadroparin group(n = 278) and the fondaparinux sodium group(n = 314) according to the types of anticoagulants used. Anticoagulant therapy began 12-24 h after operation and continued until discharge. DVT prevalence between two groups was compared. The Statistical Package for Social Sciences (SPSS) software version 25 (SPSS, Armonk, NY, USA) was used for statistical analysis. RESULTS: The prevalence of DVT in the nadroparin group and the fondaparinux sodium group was 8.3% (23/278) and 15.0% (47/314), respectively(p = 0.012). Statistical analysis showed that nadroparin group showed a lower prevalence of thrombosis than fondaparinux group (OR = 1.952, P = 0.012). Subgroup analyses showed that nadroparin group had a lower prevalence of DVT than fondaparinux group in some special patients groups such as female patients (OR = 2.258, P = 0.007), patients who are 65-79 years old (OR = 2.796, P = 0.004), patients with hypertension (OR = 2.237, P = 0.042), patients who underwent TKA (OR = 2.091, P = 0.011), and patients who underwent combined spinal-epidural anesthesia (OR = 2.490, P = 0.003) (P < 0.05). CONCLUSION: Nadroparin may have an advantage over fondaparinux sodium in preventing DVT in lower extremities after THA and TKA.


Assuntos
Anticoagulantes , Artroplastia de Quadril , Artroplastia do Joelho , Fondaparinux , Nadroparina , Complicações Pós-Operatórias , Tromboembolia Venosa , Humanos , Fondaparinux/uso terapêutico , Feminino , Masculino , Estudos Retrospectivos , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Nadroparina/uso terapêutico , Nadroparina/administração & dosagem , Pessoa de Meia-Idade , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/epidemiologia , Idoso , Anticoagulantes/uso terapêutico , Anticoagulantes/administração & dosagem , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/cirurgia , Resultado do Tratamento
2.
Opt Express ; 32(4): 5705-5717, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38439289

RESUMO

We propose a large viewing angle integral imaging 3D display system based on a symmetrical compound lens array (SCLA). The display system comprises a high-resolution 2D display panel, an SCLA, and a light shaping diffuser. The high-resolution 2D display panel presents an elemental image array, the SCLA modulates the light rays emitted from the 2D display panel to form 3D images in space, and the light shaping diffuser eliminates the gaps between 3D pixels of the 3D images. We find that the lateral aberration is a crucial factor that affects the resolution of the reconstructed 3D image. The symmetrical structure of the SCLA enables a reduced focal length and the elimination of lateral aberration, improving the viewing angle and the 3D image resolution simultaneously. The experimental results confirm that the proposed display system increases the viewing angle to 68.6°, achieving a comparable resolution of the full field of view while maintaining a simple structure.

3.
Opt Express ; 30(25): 44580-44593, 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36522880

RESUMO

Depth of field (DOF) and resolution are mutually restricted in integral imaging (II) display. To overcome the trade-offs, we propose an II display system that simultaneously enhances the DOF and resolution. The system consists of a transmissive mirror device (TMD), a semi-transparent mirror (STM), and two II display units. Each II display unit consists of a 4K display screen and a micro-lens array (MLA). Benefiting from the parallel placement of the TMD and the STM, two central depth planes are reconstructed, which effectively enhances the DOF. Meanwhile, the resolution in the overlapping DOF region is increased to two times due to the interpolation of the light field information from two II display units. The impact of the distance between the two II display units and the TMD on the 3D image quality is analyzed. In geometric optics, a distance between the II two display units and the TMD is optimized to eliminate ghost images. In wave optics, a distance is optimized to eliminate 3D pixel gaps by exploiting the diffraction effect of the TMD. Both the geometric and wave optics are considered simultaneously to obtain a high-quality 3D image without ghost images and 3D pixel gaps. A DOF and resolution-enhanced II display system is developed, and the experimental results verify its feasibility.

4.
Opt Lett ; 47(18): 4628-4631, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36107049

RESUMO

We propose a system to eliminate the graininess of an integral imaging 3D display by using a transmissive mirror device (TMD). The proposed system consists of a 2D display, a micro-lens array (MLA), and a TMD. The TMD comprises square apertures with mirror-reflective inner wall. The light rays pass through the square aperture to form a diffraction spot, and the diffraction light intensity has a Sinc-function distribution. Therefore, the TMD can be used as an optical low-pass filter. In a certain imaging range, the mainlobe of the Sinc-function distribution is almost unchanged. The TMD has the property of a volumetric optical low-pass filter. It can interpolate the interval between discrete 3D pixels. Therefore, the TMD can be used to eliminate the graininess. The resolution of the 3D image is improved by 2.12 times. The experimental results verify the feasibility of the proposed system.

5.
Orthop Surg ; 14(11): 2871-2877, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36125199

RESUMO

OBJECTIVE: Neuropathic pain (NP) plays an important role in patients with knee osteoarthritis (KOA). However, the prevalence of NP at different treatment stages including outpatient, awaiting and after total knee arthroplasty (TKA) have not been compared. The understanding of this issue and identify risk factors can help physicians develop individualized strategies to manage the pain of KOA. Therefore, the aim of the study is to investigate the prevalence and risk factors of NP at different treatment stages of KOA. METHODS: Patients diagnosed as KOA between August 2016 and August 2020 were enrolled in this cross-sectional study and divided into three groups according to treatment stage, including outpatient stage, awaiting TKA stage (pre-TKA) and after TKA stage (post-TKA). A numeric rating scale (NRS) and PainDETECT questionnaire were used to evaluate nociceptive pain and NP. Patient demographics, radiological assessments using Kellgren-Lawrence (K-L) grade, and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) scores were analyzed. Data analysis and statistics were processed using SPSS 20.0 and examined by ANOVA with/without Bonferroni correction or Kruskal-Wallis test. A chi-square test was used to determine cross-table data and calculate the odds ratio (OR) value. RESULTS: Of the 921 patients, the prevalence of possible and likely NP was 17.5% (56/320) and 2.5% (8/320) in the pre-TKA group compared with 3.4% (8/233) and 0.4% (1/233) in the outpatient group and 1.4% (5/368) and 0.5% (2/368) in the post-TKA group, respectively. In the pre-TKA group, higher NRS (NRS >3; OR = 10.65, 95% CI: 3.25-34.92, P < 0.001) and WOMAC pain score (score > 10; OR = 4.88, 95% CI: 2.38-10.01, P < 0.001) conferred an increased risk of unclear pain. Age, gender, BMI and K-L grade showed no significant differences among the unlikely, possible and likely NP groups. CONCLUSION: Prevalence of NP is different at stages of out-patient, awaiting and after TKA in patients with KOA. Patients awaiting TKA have the highest prevalence of NP compared with patients in outpatient and post-TKA groups. In the patients waiting for TKA, higher NRS (NRS >3) and WOMAC pain scores (score > 10) are risk factors of NP.


Assuntos
Artroplastia do Joelho , Neuralgia , Osteoartrite do Joelho , Humanos , Osteoartrite do Joelho/cirurgia , Pacientes Ambulatoriais , Prevalência , Estudos Transversais , Neuralgia/cirurgia , Fatores de Risco , Articulação do Joelho/cirurgia , Resultado do Tratamento
6.
Opt Express ; 29(23): 37464-37475, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808817

RESUMO

A four-mode 2D/3D switchable display using a 1D/2D convertible liquid crystal (LC) lens array is proposed in this paper. The LC lens array is composed of two orthogonal LC lens arrays, with a λ/2 film in the middle to rotate the polarization by 90°. Based on the LC lens array, a four-mode 2D/3D switchable display is realized, which is switchable between the turn-off and turn-on states: when the operating voltage V1 = 0, V2 = 0, the display operates in mode I, which is 2D display; when the operating voltage V1 = 0, V2 = 0, the display operates in mode II, and the 3D display effect is in x direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode III, and the 3D display effect is in y direction; when the operating voltage V1 = 0, V2 = 0, the display operates in mode IV, the 3D display effect is in x-y plane. Experimental results indicate that the LC lens array has simple fabrication process, low operating voltage (∼5.4V), and short focal length. Moreover, based on the designed LC lens array, the 2D/3D switchable display shows no moiré pattern.

7.
Appl Opt ; 58(34): G276-G281, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31873510

RESUMO

In this paper, we present a 2D/3D mixed system with high image quality based on integral imaging and a switchable diffuser element. The proposed system comprises a liquid crystal display screen, lens array, switchable diffuser element and projector. The switchable diffuser element can be controlled to present 2D/3D mixed images or 2D and 3D images independently, and can reduce the Moire fringe and black grid. In addition to the improved display quality, the proposed system has advantages of a simple structure and is low cost, which contribute to the portability and practicability.

8.
Light Sci Appl ; 8: 67, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31666943

RESUMO

Integral imaging is a promising three-dimensional (3D) imaging technique that captures and reconstructs light field information. Microlens arrays are usually used for the reconstruction process to display 3D scenes to the viewer. However, the inherent chromatic aberration of the microlens array reduces the viewing quality, and thus, broadband achromatic imaging remains a challenge for integral imaging. Here, we realize a silicon nitride metalens array in the visible region that can be used to reconstruct 3D optical scenes in the achromatic integral imaging for white light. The metalens array contains 60 × 60 polarization-insensitive metalenses with nearly diffraction-limited focusing. The nanoposts in each high-efficiency (measured as 47% on average) metalens are delicately designed with zero effective material dispersion and an effective achromatic refractive index distribution from 430 to 780 nm. In addition, such an achromatic metalens array is composed of only a single silicon nitride layer with an ultrathin thickness of 400 nm, making the array suitable for on-chip hybrid-CMOS integration and the parallel manipulation of optoelectronic information. We expect these findings to provide possibilities for full-color and aberration-free integral imaging, and we envision that the proposed approach may be potentially applicable in the fields of high-power microlithography, high-precision wavefront sensors, virtual/augmented reality and 3D imaging.

9.
J Opt Soc Am A Opt Image Sci Vis ; 36(4): 588-593, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044978

RESUMO

An augmented reality (AR) three-dimensional (3D) display based on one-dimensional integral imaging (1DII), by using a lenticular lens array holographic optical element (LLA-HOE), is proposed. The 3D image of the 1DII has higher vertical resolution compared with the image of conventional integral imaging whose resolution is sharply reduced for providing quasi-continuous viewpoints in both the horizontal and vertical directions. The proposed 3D display consists of a projector and an LLA-HOE and is compact. As an image combiner, the LLA-HOE can diffract Bragg-matched light rays that have the same wavelength and incident angle as the original reference wave; it can also function as a lenticular lens array to reconstruct a 3D image but transmit other light rays emitted from the surroundings. In the experiment, an LLA-HOE of 80 mm×80 mm size is recorded, and a combination of a high-resolution 3D virtual image and a real 3D object is presented by the proposed AR 3D display.

10.
Opt Lett ; 44(2): 387-390, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-30644907

RESUMO

An integral imaging-based 2D/3D convertible display system is proposed by using a lens-array holographic optical element (LAHOE), a polymer dispersed liquid crystal (PDLC) film, and a projector. The LAHOE is closely attached to the PDLC film to constitute a projection screen. The LAHOE is used to realize integral imaging 3D display. When the PDLC film with an applied voltage is in the transparent state, the projector projects a Bragg matched 3D image, and the display system works in 3D mode. When the PDLC film without an applied voltage is in the scattering state, the projector projects a 2D image, and the display system works in 2D mode. A prototype of the integral imaging-based 2D/3D convertible display is developed, and it provides 2D/3D convertible images properly.

11.
Opt Express ; 26(9): 11084-11099, 2018 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-29716046

RESUMO

This paper realizes an optical 3D images encryption and reconstruction by employing the geometric calibration algorithm to the monospectral synthetic aperture integral imaging system. This method has the simultaneous advantages of improving the quality of 3D images by eliminating the crosstalk from the unaligned cameras and increasing security of the multispectral 3D images encryption by importing the random generated maximum-length cellular automata into the Fresnel transform encoding algorithm. Furthermore, compared with the previous 3D images encryption methods of encrypting 3D multispectral information, the proposed method only encrypts monospectral data, which will greatly minimize the complexity. We present experimental results of 3D image encryption and volume pixel computational reconstruction to test and verify the performance of the proposed method. Experimental results validate the feasibility and robustness of our proposed approach, even under severe degradation.

12.
Appl Opt ; 57(4): 952-958, 2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29400773

RESUMO

In this paper, we propose a dual-view-zone tabletop 3D display system based on integral imaging by using a multiplexed holographic optical element (MHOE) that has the optical properties of two sets of microlens arrays. The MHOE is recorded by a reference beam using the single-exposure method. The reference beam records the wavefronts of a microlens array from two different directions. Thus, when the display beam is projected on the MHOE, two wavefronts with the different directions will be rebuilt and the 3D virtual images can be reconstructed in two viewing zones. The MHOE has angle and wavelength selectivity. Under the conditions of the matched wavelength and the angle of the display beam, the diffraction efficiency of the MHOE is greatest. Because the unmatched light just passes through the MHOE, the MHOE has the advantage of a see-through display. The experimental results confirm the feasibility of the dual-view-zone tabletop 3D display system.

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