ObjectiveThe widespread adoption of portable fundus cameras for primary care and community screening is hindered by limitations in current autofocus(AF) technologies. Image-based methods relying on sharpness evaluation require iterative searches, resulting in slow convergence, while projection-based techniques are susceptible to optical artifacts and calibration errors. To address these challenges, this study introduces a novel AF system based on direct wavefront sensing, designed to deliver simultaneous high speed, high precision, and operational robustness within the compact form factor essential for portable ophthalmic devices. MethodsOur approach fundamentally reimagines the AF process by directly measuring the ocular wavefront aberration. We developed a custom portable fundus camera integrating a miniaturized Shack-Hartmann wavefront sensor (SHWS) into the optical path. An 850 nm laser diode projects a point source onto the retina via oblique illumination to minimize corneal reflections. Light scattered from this spot carries the eye’s refractive error through the imaging optics and is directed to the SHWS, positioned at a plane optically conjugate to the primary color CMOS imaging sensor. A microlens array within the SHWS samples the incident wavefront, generating a pattern of focal spots on a CCD. Real-time centroid analysis of these spots provides a map of local wavefront slopes. These measurements are processed through a singular value decomposition (SVD) algorithm to fit a Zernike polynomial basis set, enabling real-time reconstruction of the wavefront phase. The defocus component (S) is extracted from the second-order Zernike coefficients, providing a direct, quantitative measure of the refractive error in diopters. This value serves as a precise error signal in a closed-loop control system, which commands a voice-coil actuated focusing lens to its null position in a single, deterministic step, eliminating the need for iterative search algorithms. ResultsComprehensive evaluation demonstrated the system’s high performance. Testing on a calibrated model eye (OEMI-7) established a highly linear relationship between the computed defocus S and the focusing lens position across a ±20 Diopter (D) compensation range, achievable within a 5 mm mechanical travel. The system achieved a focusing precision of 0.08 D, corresponding to an 18-fold improvement over a conventional projection spot-size method tested under identical conditions. The total focus acquisition time, encompassing wavefront measurement, computation, and lens actuation, averaged under 0.5 s. Clinical validation with 25 human volunteers (50 eyes, refractive range -15 D to +10 D) confirmed practical efficacy. The wavefront-sensing AF succeeded in 92% of attempts with a mean time of 0.5 s, substantially outperforming a projection-based benchmark which achieved only a 32% success rate with an average time of 4.25 s. The system provided instantaneous directional guidance and maintained stability during minor ocular movements. Objective assessment of image quality, via amplitude contrast of retinal vasculature, showed consistent and significant enhancement following AF correction across the entire tested diopter range. ConclusionThis work successfully implements and validates a direct wavefront-sensing autofocus paradigm for portable fundus cameras. By directly quantifying and compensating for the optical defocus aberration, this method bypasses the fundamental limitations of image-processing and projection-based techniques, enabling rapid, precise, and deterministic diopter compensation. The developed system delivers an exceptional combination of a wide operational range (±20 D), high accuracy (0.08 D), fast convergence (0.5 s), and a compact physical footprint. This technology provides a practical and high-performance focusing solution capable of enhancing the reliability, throughput, and diagnostic utility of portable retinal imaging in large-scale screening applications. Future efforts will be directed towards system cost optimization and performance adaptation for diverse ocular conditions.

Objective To explore the effectiveness of the peripheral arterial calcification scoring system(PACSS)based on computed tomography angiography(CTA)in assessing renal function in patients with peripheral arterial disease(PAD).Methods The clinical data,CTA imaging data,and laboratory results from PAD patients who underwent lower limb artery CTA examination were retrospectively collected.The PACSS was utilized to score the calcification in both lower limb arteries.Participants were categorized into three groups based on their estimated glomerular filtration rate(eGFR)(normal group:eGFR≥90 mL/min;mild renal dysfunction group:eGFR 60-89 mL/min,and moderate to severe renal dysfunction group:eGFR＜60 mL/min).The demographic data,clinical symptoms,and comorbidities among the three groups were compared by analysis of variance(ANOVA).The Spearman correlation coefficient was employed to evaluate the relationship between eGFR,cystatin C,and PACSS score.Results The age(P＜0.001)and PACSS score(P＜0.05)of patients with renal dysfunction were significantly higher than those of patients with normal renal function.However,there were no significant differences in gender,prevalence of diabetes,hypertension,or severe limb ischemia.Spearman correlation analysis showed that eGFR was negatively correlated with PACSS score(r=-0.18 in the right lower limb,P=0.037,r=-0.24 in the left lower limb,P=0.006).In contrast,cystatin C was positively correlated with PACSS score(r=0.26 in the right lower limb,P＜0.001,r=0.22 in the left lower limb,P=0.002).Conclusion The PACSS score of lower limb artery in PAD patients is corre-lated with the severity of renal dysfunction.This finding may facilitate early warning and clinical intervention for PAD patients with renal dysfunction.

Objective To explore the clinical value of energy-spectrum CT single-energy imaging in enhancing the image quality and stent display of stent placement CT angiography(CTA)in lower extremity atherosclerotic occlusive disease.Methods Twenty patients[mean(65.61±9.65)years;male/female,16/4]who underwent stenting for chronic occlusive disease of the lower extremity arteries by lower extremity arterial energetic spectral CTA were retrospectively recruited at our hospital.The original images were reconstructed into seven sets of single energy(40-100 keV),120 kVp,virtual unenhanced images(VUE)and metal artifact reduction(MAR)technique images.Images were debossed and then scaffolded for display with volumetric reconstruction(VR),maximum density projection(MIP)and curve planar reconstruction(CPR),and were objectively and subjectively assessed and compared using one-way analysis of variance(ANOVA).Results The 80 keV and MAR images had the highest scores compared to the other reconstruction group images(P＜0.01).Conclusion 80 keV single-energy imaging and de-metallization artifacts MAR improve the image quality of lower extremity arterial stent lumen and structure display;therefore,they have higher diagnostic value for clinicians.

Objective To develop a single-person breast surgery teaching system to improve the teaching efficiency of breast surgery.Methods The single-person breast surgery teaching system consisted of a magnetic suspension and retraction device and a breast model.The magnetic suspension and retraction device was composed of a magnetic suspension component and a magnetic retraction component,of which,the magnetic suspension component included a bracket,an outer magnet and an inner magnet and the magnetic retraction component comprised a magnetic base and an elastic grasping forceps.The breast model was established with porcine abdominal tissue obtained from slaughterhouses.Twelve surgical trainees were randomized into an experimental group(n=6)and a control group(n=6),and the 2 groups performed flap release operations on the breast model with skin-preserving mastectomy as the target procedure.The operation was carried out with the developed system in the experimental group and with the traditional procedure in the control group.Results The two groups had the flap-free operation on the breast model finished successufully,which had no significant differences in the length of incision(P>0.05);the experimental group gained advantages over the control group in the number of assistants required,operation time,times of skin flap injuries,times of glandular injuries and effect of exposure,with the differences being statistically significant(all P<0.05).Conclusion The single-person breast surgery teaching system enhances the effect of exposure efficiently,meets the reequirements for single-person training and improves the teaching efficiency.[Chinese Medical Equipment Journal,2025,46(7):34-38]

Objective To explore the clinical value of energy-spectrum CT single-energy imaging in enhancing the image quality and stent display of stent placement CT angiography(CTA)in lower extremity atherosclerotic occlusive disease.Methods Twenty patients[mean(65.61±9.65)years;male/female,16/4]who underwent stenting for chronic occlusive disease of the lower extremity arteries by lower extremity arterial energetic spectral CTA were retrospectively recruited at our hospital.The original images were reconstructed into seven sets of single energy(40-100 keV),120 kVp,virtual unenhanced images(VUE)and metal artifact reduction(MAR)technique images.Images were debossed and then scaffolded for display with volumetric reconstruction(VR),maximum density projection(MIP)and curve planar reconstruction(CPR),and were objectively and subjectively assessed and compared using one-way analysis of variance(ANOVA).Results The 80 keV and MAR images had the highest scores compared to the other reconstruction group images(P＜0.01).Conclusion 80 keV single-energy imaging and de-metallization artifacts MAR improve the image quality of lower extremity arterial stent lumen and structure display;therefore,they have higher diagnostic value for clinicians.

Testicular histology based on testicular biopsy is an important factor for determining appropriate testicular sperm extraction surgery and predicting sperm retrieval outcomes in patients with azoospermia. Therefore, we developed a deep learning (DL) model to establish the associations between testicular grayscale ultrasound images and testicular histology. We retrospectively included two-dimensional testicular grayscale ultrasound from patients with azoospermia (353 men with 4357 images between July 2017 and December 2021 in The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, China) to develop a DL model. We obtained testicular histology during conventional testicular sperm extraction. Our DL model was trained based on ultrasound images or fusion data (ultrasound images fused with the corresponding testicular volume) to distinguish spermatozoa presence in pathology (SPP) and spermatozoa absence in pathology (SAP) and to classify maturation arrest (MA) and Sertoli cell-only syndrome (SCOS) in patients with SAP. Areas under the receiver operating characteristic curve (AUCs), accuracy, sensitivity, and specificity were used to analyze model performance. DL based on images achieved an AUC of 0.922 (95% confidence interval [CI]: 0.908-0.935), a sensitivity of 80.9%, a specificity of 84.6%, and an accuracy of 83.5% in predicting SPP (including normal spermatogenesis and hypospermatogenesis) and SAP (including MA and SCOS). In the identification of SCOS and MA, DL on fusion data yielded better diagnostic performance with an AUC of 0.979 (95% CI: 0.969-0.989), a sensitivity of 89.7%, a specificity of 97.1%, and an accuracy of 92.1%. Our study provides a noninvasive method to predict testicular histology for patients with azoospermia, which would avoid unnecessary testicular biopsy.
Humans ; Male ; Azoospermia/diagnostic imaging* ; Deep Learning ; Testis/pathology* ; Retrospective Studies ; Adult ; Ultrasonography/methods* ; Sperm Retrieval ; Sertoli Cell-Only Syndrome/diagnostic imaging*

Objective:To investigate the clinical characteristics and prognosis of acute pancreatitis (AP) with different etiologies.Methods:The retrospective cohort study was conducted. The clinical data of 702 patients with AP who were admitted to Xuanwu Hospital of Capital Medical University from January 2018 to December 2022 were collected. There were 451 males and 251 females,aged (52±17)years. Observation indicators: (1) clinical characteristics of AP patients with different etiologies; (2) complications and prognosis of AP patients with different etiologies; (3) complications and prognosis of moderately severe and severe AP patients with different etiologies. Comparison of measurement data with normal distribution among multiple groups was conducted using the one-way analysis of variance. Comparison of measurement data with skewed distribution among multiple groups was conducted using the Kruskal-Wallis H test. Comparison of count data among multiple groups was conducted using the chi-square test. Results:(1) Clinical characteris-tics of AP patients with different etiologies. Of the 702 AP patients, 434 cases were biliary AP, 199 cases were hypertriglyceridemic-induced AP,29 cases were alcoholic AP, and 40 cases were idiopathic AP. There were significant differences in gender,age,body mass index,combined cardiovascular disease,combined diabetes,combined nephrosis,disease severity and modified computed tomography severity index among AP patients with different etiologies ( χ2=24.61, F=48.65, 12.24, χ2=13.67, 12.90, 14.12, 15.56, H=17.62, P<0.05). (2) Complications and prognosis of AP patients with different etiologies. There was no significant difference in infectious pancreatic necrosis,duration of intensive care unit stay,total duration of hospital stay, and death of patients during hospitalization among AP patients with different etiologies ( P>0.05). (3) Complications and prognosis of moderately severe and severe AP patients with different etiologies. Of the 395 patients with moderately severe and severe AP, 217 cases were biliary AP, 128 cases were hypertriglyceridemic-induced AP, 19 cases were alcoholic AP, and 31 cases were idiopathic AP. There were significant differences in renal injury, multiple organ dysfunction syndrome and walled-off necrosis among moderately severe and severe AP patients with different etiologies ( χ2=12.62, 8.25, 14.33, P<0.05), and there was no significant difference in infectious pancreatic necrosis, lung injury, circulation system injury, duration of intensive care unit stay, total duration of hospital stay, or death of patients during hospitalization among moderately severe and severe AP patients with different etiologies ( P>0.05). Conclusions:The clinical charac-teristics vary among AP patients with different etiologies. The risk of complications varies among moderately severe and severe AP patients with different etiologies.

Objective To explore the mechanism of myocardial toxicity caused by N-methyl-3,4-methyle-nedioxyamphetamine(MDMA),the changes of intracellular calcium oscillation mode and calcium han-dling proteins during acute exposure to different concentrations of MDMA were detected,and the in-volvement of nuclear factor κB(NF-κB)and its effect on calcium handling proteins were investigated.Methods Primary rat cardiomyocytes were cultured to establish MDMA acute exposure model,and a control group was set up.The MDMA poisoning model was divided into three concentration groups of 10,100 and 1 000 μmol/L.After 1 h of exposure,the morphological changes of cardiomyocytes were ob-served,the cytotoxicity and changes in calcium signals were measured,and the changes in calcium handling proteins RyR2,SERCA2a,PLN,NCX1 and Cav1.2 were detected.The changes of NF-κB activity and the expression of nucleoprotein p-p65(Ser311)and PKCζ after MDMA exposure,and the intervention of NF-κB inhibitors pyrrolidine dithiocarbamate ammonium(PDTC)and protein kinase C(PKC)inhibitor chelerythrine(CHE)were detected by electrophoretic mobility shift assay(EMSA)and Western blotting.The effects of PDTC intervention on calcium signals,and the expressions of RyR2,SERCA2a,PLN,NCX1 and Cav1.2 after acute MDMA exposure were also observed.Results No obvious changes were observed in the morphology of cardiomyocytes after acute exposure to MDMA,whereas the oscillation waveform of intracytoplasmic calcium ion showed irregular changes with increased oscillation amplitude,intense fluctuations,irregular frequency,and increased fluctuation range of relative optical density values.The expression of RyR2,SERCA2a and NCX1 increased,while the expression of Cav1.2 and PLN de-creased.Acute MDMA exposure could increase NF-κB activity,while PDTC and CHE intervention could inhibit NF-κB activity.In MDMA exposed group,the expression of PKCζ and nucleoprotein p-p65(Ser311)both increased and could be inhibited by CHE.After the intervention of PDTC to block NF-κB,the amplitude of calcium oscillation was lower than that of the MDMA exposed group,and the expres-sion of RyR2,SERCA2a and NCX1 decreased.There was no significant change in PLN,while the ex-pression of Cav1.2 increased.Conclusion MDMA can lead to an increase of calcium ion concentration in cardiomyocytes.Calcium ions are involved in myocardial toxicity of MDMA.The mechanism is re-lated to changes in calcium handling proteins,mainly associated with the increased expression of RyR2.MDMA can up-regulate the intracellular activity of NF-κB through the PKCζ-NF-κB pathway and affect calcium handling proteins,which aggravate intracellular calcium overload during acute MDMA exposure.

Objective:To investigate the value of biparametric-MRI (bpMRI) based peritumoral radiomics for preoperative prediction of extraprostatic extension (EPE) in prostate cancer (PCa).Methods:In this cross-sectional study, consecutive bpMRI of patients undergoing prostatectomy for PCa were retrospectively collected from the First Medical Center (center 1) and the Third Medical Center (center 2) of Chinese PLA General Hospital. A total of 274 patients were finally enrolled. Patients at center 1 from January 2020 to December 2022 were randomly divided into a training set (149 cases) and an internal validation set (63 cases) by stratified random sampling. Patients at center 2 from January 2023 to March 2024 were assigned to the external test set (62 cases). Patients were categorized into EPE-positive group and EPE-negative group according to pathological assessment postoperatively. In the training set, there were 49 cases in EPE-positive group and 100 cases in EPE-negative group. In the internal validation set, there were 26 cases in EPE-positive group and 37 cases in EPE-negative group. In the external test set, there were 22 cases in EPE-positive group and 40 cases in EPE-negative group. Axial T 2WI and apparent diffusion coefficient (ADC) images were manually annotated to obtain index lesion regions of interest (ROIs), with the peritumoral ROIs subsequently delineated by semi-automatic segmentation technique. Radiomics features were extracted from intra-tumoral, peri-tumoral, and intra-tumoral plus peri-tumoral ROIs. The training set data was employed to select and optimize features to build the radiomics models. The logistic regression analysis was used to develop radiomics, clinical, and integrated models. The predictive performance was assessed by the area under the receiver operating characteristic curve (AUC) in the external test set, and compared by the DeLong test. The sensitivity and specificity were compared by the exact McNemar test. Results:In the external test set, the peri-tumoral radiomics model based on bpMRI showed the highest performance in evaluating EPE, with an AUC of 0.739 (95% CI 0.611-0.842), which was identified as the optimal radiomics model. EPE grade ( OR=6.151, 95% CI 3.371-11.226, P<0.001) was incorporated into the clinical model, with an AUC of 0.780 (95% CI 0.657-0.875) in the external test set. The integrated model had an AUC of 0.817 (95% CI 0.698-0.904) in the external test set. There was no statistically significant difference in comparisons of AUCs among the three models (all P>0.05). The sensitivity of the integrated model (68.2%) showed no significant difference from those of the clinical model and the optimal radiomics model (77.3% and 86.4%, respectively; P=0.500 and P=0.289). However, the specificity of the integrated model (85.0%) was significantly higher than those of the clinical model (67.5%, P=0.016) and the optimal radiomics model (50.0%, P<0.001). Conclusion:A bpMRI-based peritumoral radiomics integrating clinical model demonstrates high performance for preoperative prediction of EPE in PCa.

Gene therapy, harnessing the power of CRISPR-Cas9 and/or DNAzyme systems, stands as a pivotal approach in cancer therapy, enabling the meticulous manipulation of genes pivotal to tumorigenesis and immunity. However, the pursuit of precise gene therapy encounters formidable hurdles. Herein, a near-infrared upconversion theranostic nanomachine is devised and tailors for CRISPR-Cas9/DNAzyme systems mediate precise gene therapy. An ingenious logic DNAzyme system consists of Chain 1 (C1)/Chain 2 (C2) and endogenous lncRNA is designed. We employ manganese modified upconversion nanoparticles for carrying ultraviolet-responsive C1-PC linker-C2 (C₂P) chain and Cas9 ribonucleoprotein (RNP), with outermost coats with hyaluronic acid. Upon reaching tumor microenvironment (TME), the released Mn²⁺ ions orchestrate a trifecta: facilitating endosomal escape, activating cGAS-STING signaling, and enabling T1-magnetic resonance imaging. Under near-infrared irradiation, Cas9 RNP/C₂P complex dissociates, releasing Cas9 RNP into the nucleus to perform gene editing of Ptpn2, while C1/C2 chains self-assemble with endogenous lncRNA to form a functional DNAzyme system, targeting PD-L1 mRNA for gene silencing. This strategy remodels the TME by activating cGAS-STING signaling and dual immune checkpoints blockade, thus realizing tumor elimination. Our theranostic nanomachine armed with the CRISPR-Cas9/DNAzyme logic systems, represents a resourceful and promising strategy for advancing cancer systemic immunotherapy and precise gene therapy.