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 evaluate the short-term clinical efficacy of external fixation and internal fixation with steel plate in the treatment of unstable distal radius fractures (AO-23C type), based on the principles of Chinese osteosynthesis (CO). METHODS: Forty-eight patients with unstable distal radius fractures between January 2022 and February 2023 were retrospectively analyzed and divided into the CO external fixation group and internal fixation group. CO external fixation group consisted of 25 patients, including 7 males and 18 females, aged from 37 to 56 years old with an average of ( 52.6±11.3) years old. Among them, there were 7 patients of traffic accidents and 18 patients of falls, resulting in a total of 25 patients of closed fractures and no open fractures, the treatment was conducted using closed reduction and CO external fixation. The internal fixation group consisted of 23 patients, comprising 8 males and 15 females, age ranged from 41 to 59 years old, with an average age of(53.3±13.7) years old. Among them, 8 patients resulted from car accidents while the remaining 15 patients were caused by falls. All 23 patients were closed fractures without any open fractures observed. The technique of open reduction and internal fixation with steel plate was employed. The perioperative data, including injury-operation time, operation duration, blood loss, and length of hospital stay, were assessed in both groups. Additionally, the QuickDASH score and visual analogue scale (VAS) were evaluated. Range of motion and grip strength assessment, imaging findings such as palmar inclination angle, ulnar declination angle, radius length, articular surface step, intra-articular space measurements were also examined along with any complications. RESULTS: The follow-up duration ranged from 0 to 24 months, with an average duration of (16.0±3.8) months. The CO external fixation exhibited significantly shorter time from injury to operation (2.4±3.3) d vs (7.4±3.7) d, shorter operation duration (56.27±15.23) min vs (74.10±5.26) min, lower blood loss (14.52±6.54) ml vs (32.32±10.03) ml, and reduced hospitalization days (14.04±3.24 )d vs (16.45±3.05) d compared to the internal fixation group (P<0.05). The QuickDASH score at 12 months post-operation was (8.21±1.64) in the CO external fixation group, while no significant difference was observed in the internal fixation group (7.04±3.64), P>0.05. There were no statistically significant differences in VAS between two groups at 6 weeks, as well as 1 and 3 months post-surgery (P>0.05). Additionally, there were no significant disparities observed in terms of range of motion and grip strength between two groups at the 2-year follow-up after the operation (P>0.05). After 12 months of surgery, the CO external fixation group exhibited a significantly smaller palmar inclination angle (17.90±2.18) ° vs (19.87±3.21) °, reduced articular surface step (0.11±0.03) mm vs (0.17±0.02) mm, and shorter radius length (8.16±1.11) mm compared to the internal fixation group (9.59±1.02) mm, P<0.05. The ulnar deviation angle and intra-articular space did not show any significant difference between two groups (P>0.05). The reduced fell within the allowable range between the CO external fixation group (23 out of 25 cases) and the internal fixation group (21 out of 23 cases) was not statistically significant (P=0.29). There was no significant difference in complications between the two groups(P>0.05). CONCLUSION Both the CO external fixation and open reduction with plate internal fixation demonstrate clinical efficacy in managing unstable distal radius fractures. The CO external fixation offers advantages in shorter injury-to-operation times, reduced intraoperative blood loss, and decreased surgical durations, while radial shortening is more effectively controlled by internal fixation.
Humans ; Male ; Female ; Middle Aged ; Radius Fractures/physiopathology* ; Adult ; Bone Plates ; Fracture Fixation, Internal/methods* ; External Fixators ; Retrospective Studies ; Fracture Fixation/methods* ; Wrist Fractures

OBJECTIVE: To explore clinical efficacy of tibial transverse transport (TTT) combined with debridement in treating necrotizing fasciitis of the lower extremities. METHODS: A retrospective analysis was conducted on 31 patients with necrotizing fasciitis of the lower extremities who were treated with TTT from January 2021 to October 2023, including 28 males and 3 females, aged from 44 to 76 years old with an average of (57.58±8.79) years old. In-hospital mortality rate, amputation rate, length of hospital stay, hospitalization cost, number of surgeries, and inflammatory indicators before and after operation (white blood cells, hemoglobin, C-reactive protein, albumin), as well as wound healing and daily living ability were observed and compared. RESULTS: All 31 patients were followed up for 3 to 12 months with an average of (6.61±2.46) months. All patients' wounds healed without recurrence. The wound healing time was (4.96±2.61) months, amputation rate of 31 patients was 3.22% (1/31), in-hospital mortality rate was 0%, the length of hospital stay was (27.10±24.51) days, the hospitalization cost was (107, 300 ± 83, 300) yuan, and the number of surgeries was (3.26±1.93) times. White blood cells, C-reactive protein and albumin before operation were (13.41±5.54) ×10⁹/L, (136.67±73.50) mg·L^-1 and (25.92±5.59) g·L^-11 respectively, and improved to (11.05±3.65) ×10⁹/L, (79.91±51.40) mg·L^-1, and (30.31±4.02) g·L^-1 at 2 weeks after operation, and the differences were statistically significant (P<0.05);there was no statistically significant difference in hemoglobin before and after operation (P>0.05). At the latest follow-up, 16 patients were able to take care of themselves, 12 patients were partially self-sufficient, and 3 patients were completely unable to take care of themselves. CONCLUSION TTT with debridement could achieve satisfactory clinical efficacy in treating necrotizing fasciitis of the lower extremities.
Humans ; Male ; Female ; Middle Aged ; Aged ; Adult ; Fasciitis, Necrotizing/mortality* ; Retrospective Studies ; Debridement ; Lower Extremity/surgery* ; Tibia/surgery*

Objective： The aim of this study is to explore the predictive value of biparametric magnetic resonance imaging(bpMRI)for pelvic lymph node metastasis in prostate cancer patients with PSA≤20 μg/L and establish a nomogram. Methods： The imaging data and clinical data of 363 patients undergoing radical prostatectomy and pelvic lymph node dissection in the First Affiliated Hospital of Nanjing Medical University from July 2018 to December 2023 were retrospectively analyzed. Univariate analysis and multivariate logistic regression were used to screen independent risk factors for pelvic lymph node metastasis in prostate cancer, and a nomogram of the clinical prediction model was established. Calibration curves were drawn to evaluate the accuracy of the model. Results： Multivariate logistic regression analysis showed extrocapusular extension (OR=8.08,95%CI=2.62－24.97, P<0.01), enlargement of pelvic lymph nodes (OR=4.45,95%CI=1.16－17.11,P=0.030), and biopsy ISUP grade(OR=1.97,95%CI=1.12－3.46, P=0.018)were independent risk factors for pelvic lymph node metastasis. The C-index of the prediction model was 0.834, which indicated that the model had a good prediction ability. The actual value of the model calibration curve and the prediction probability of the model fitted well, indicating that the model had a good accuracy. Further analysis of DCA curve showed that the model had good clinical application value when the risk threshold ranged from 0.05 to 0.70.Conclusion： For prostate cancer patients with PSA≤20 μg/L, bpMRI has a good predictive value for the pelvic lymph node metastasis of prostate cancer with extrocapusular extension, enlargement of pelvic lymph nodes and ISUP grade≥4.
Humans ; Male ; Prostatic Neoplasms/diagnostic imaging* ; Lymphatic Metastasis ; Retrospective Studies ; Nomograms ; Prostate-Specific Antigen/blood* ; Lymph Nodes/pathology* ; Pelvis ; Predictive Value of Tests ; Prostatectomy ; Lymph Node Excision ; Risk Factors ; Magnetic Resonance Imaging ; Logistic Models ; Middle Aged ; Aged

OBJECTIVE: To elucidate how spinal manipulative therapy (SMT) exerts its analgesic effects through regulating brain function in lumbar disc herniation (LDH) patients by utilizing resting-state functional magnetic resonance imaging (rs-fMRI). METHODS: From September 2021 to September 2023, we enrolled LDH patients (LDH group, n=31) and age- and sex-matched healthy controls (HCs, n=28). LDH group underwent rs-fMRI at 2 distinct time points (TPs): prior to the initiation of SMT (TP1) and subsequent to the completion of the SMT sessions (TP2). SMT was administered once every other day for 30 min per session, totally 14 treatment sessions over a span of 4 weeks. HCs did not receive SMT treatment and underwent only one fMRI scan. Additionally, participants in LDH group completed clinical questionnaires on pain using the Visual Analog Scale (VAS) and the Japanese Orthopedic Association (JOA) score, whereas HCs did not undergo clinical scale assessments. The effects on the brain were jointly characterized using the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo). Correlation analyses were conducted between specific brain regions and clinical scales. RESULTS: Following SMT treatment, pain symptoms in LDH patients were notably alleviated and accompanied by evident activation of effects in the brain. In comparison to TP1, TP2 exhibited the most significant increase in ALFF values for Temporal_Sup_R and the most notable decrease in ALFF values for Paracentral_Lobule_L (voxelwise P<0.005; clusters >30; FDR correction). Additionally, the most substantial enhancement in ReHo values was observed for the Cuneus_R, while the most prominent reduction was noted for the Olfactory_R (voxelwise P<0.005; clusters >30; FDR correction). Moreover, a comparative analysis revealed that, in contrast to HCs, LDH patients at TP1 exhibited the most significant increase in ALFF values for Temporal_Pole_Sup_L and the most notable decrease in ALFF values for Frontal_Mid_L (voxelwise P<0.005; clusters >30; FDR correction). Furthermore, the most significant enhancement in ReHo values was observed for Postcentral_L, while the most prominent reduction was identified for ParaHippocampal_L (voxelwise P<0.005; clusters >30; FDR correction). Notably, correlation analysis with clinical scales revealed a robust positive correlation between the Cuneus_R score and the rate of change in the VAS score (r=0.9333, P<0.0001). CONCLUSIONS Long-term chronic lower back pain in patients with LDH manifests significant activation of the "AUN-DMN-S1-SAN" neural circuitry. The visual network, represented by the Cuneus_R, is highly likely to be a key brain network in which the analgesic efficacy of SMT becomes effective in treating LDH patients. (Trial registration No. NCT06277739).
Humans ; Magnetic Resonance Imaging ; Intervertebral Disc Displacement/diagnostic imaging* ; Male ; Female ; Brain/diagnostic imaging* ; Adult ; Manipulation, Spinal/methods* ; Middle Aged ; Lumbar Vertebrae/physiopathology* ; Pain Management ; Rest ; Case-Control Studies

Hilar cholangiocarcinoma is insidious in onset and often causes obstructive jaundice due to bile stasis,leading to impaired liver function.For tumors with malignant obstructive jaundice,biliary drainage is often performed before surgery in clinical practice.Currently,the commonly used drainage methods are percutaneous transhepatic biliary drainage(PTBD)and endoscopic retrograde biliary drain-age(ERBD),but there are controversies over the advantages and disadvantages of the two drainage methods.PTBD drainage can often lead to tumor implantation metastasis,but the underlying mechanism remains unclear.We detected tumor cells in PTBD and ERBD bile samples from hilar cholangiocarcino-ma patients,subsequently explored their tumorigenicity and mechanisms through tumorsphere assay in vitro and xenograft tumor models in vivo.The experiments included benign gallstones group(30 cases)as a negative control,PTBD group(14 cases)and ERBD group(13 cases).Tumorsphere formation was i-dentified in 3 cases(23％)among the 13 cases of ERBD group,in 6 cases(42％)among the 14 cases of PTBD group,but there were no tumor cells or formed tumorspheres in the 30 cases of benign gallstone group.The tumor sphere formation ability of cells in the PTBD group was significantly higher than that in ERBD group.Subcutaneous xenograft tumor assays showed that tumor growth in the PTBD group was sig-nificantly higher than that in the ERBD group.Tumor cells in PTBD bile possessed stronger tumorigenici-ty compared with the ERBD group.Mechanically,stem cell transcription factor Nanog mRNA levels were significantly higher in the PTBD group compared to the ERBD group.Both tumorsphere formation and xenograft tumor growth were reduced by Nanog knockdown in three cases of the PTBD group,indicating the important roles of Nanog in tumorigenicity of PTBD group tumor cells.The half-life of Nanog mRNA was longer in PTBD group cells than in ERBD group cells,suggesting potential post-transcriptional regu-lation on Nanog mRNA.The Nanog m6A level was higher in PTBD group tumor cells compared to the ERBD group.Analysis of methyltransferases and demethylases,ALKBH5(α-ketoglutarate dependent dioxygenase alkb family homolog 5)mRNA levels were lower in the PTBD group than in the ERBD group and significantly correlated with the m6A level of Nanog.ALKBH5 knockdown led to an increase in the m6A level of Nanog,while ALKBH5 overexpression decreased the m6A level of Nanog.Dual-luciferase activity assays demonstrated that ALKBH5 knockdown significantly enhanced luciferase activity,whereas ALKBH5 overexpression reduced it.Further studies confirmed that ALKBH5 knockdown upregulated both the mRNA and protein levels of Nanog,whereas overexpressing ALKBH5 downregulated them.ALKBH5 mediated the demethylation modification of Nanog mRNA,and the lower levels of ALKBH5 expression in the PTBD group promoted Nanog's m6A modification.Overexpressing ALKBH5 decreased tumorsphere growth,while ALKBH5 knockdown increased it,which was subsequently reduced by the simultaneous Nanog knockdown again.In sum,tumor cells in PTBD and ERBD drainage bile from hilar cholangiocar-cinoma patients exhibited tumorigenicity.Compared to the ERBD group,tumor cells in PTBD bile with lower ALKBH5 expression levels enhanced Nanog's m6A modification to upregulate Nanog expression levels,resulting in stronger tumorigenicity.These findings are significant for elucidating propensity to tumor implantation metastasis from PTBD drainage.

Hilar cholangiocarcinoma is insidious in onset and often causes obstructive jaundice due to bile stasis,leading to impaired liver function.For tumors with malignant obstructive jaundice,biliary drainage is often performed before surgery in clinical practice.Currently,the commonly used drainage methods are percutaneous transhepatic biliary drainage(PTBD)and endoscopic retrograde biliary drain-age(ERBD),but there are controversies over the advantages and disadvantages of the two drainage methods.PTBD drainage can often lead to tumor implantation metastasis,but the underlying mechanism remains unclear.We detected tumor cells in PTBD and ERBD bile samples from hilar cholangiocarcino-ma patients,subsequently explored their tumorigenicity and mechanisms through tumorsphere assay in vitro and xenograft tumor models in vivo.The experiments included benign gallstones group(30 cases)as a negative control,PTBD group(14 cases)and ERBD group(13 cases).Tumorsphere formation was i-dentified in 3 cases(23％)among the 13 cases of ERBD group,in 6 cases(42％)among the 14 cases of PTBD group,but there were no tumor cells or formed tumorspheres in the 30 cases of benign gallstone group.The tumor sphere formation ability of cells in the PTBD group was significantly higher than that in ERBD group.Subcutaneous xenograft tumor assays showed that tumor growth in the PTBD group was sig-nificantly higher than that in the ERBD group.Tumor cells in PTBD bile possessed stronger tumorigenici-ty compared with the ERBD group.Mechanically,stem cell transcription factor Nanog mRNA levels were significantly higher in the PTBD group compared to the ERBD group.Both tumorsphere formation and xenograft tumor growth were reduced by Nanog knockdown in three cases of the PTBD group,indicating the important roles of Nanog in tumorigenicity of PTBD group tumor cells.The half-life of Nanog mRNA was longer in PTBD group cells than in ERBD group cells,suggesting potential post-transcriptional regu-lation on Nanog mRNA.The Nanog m6A level was higher in PTBD group tumor cells compared to the ERBD group.Analysis of methyltransferases and demethylases,ALKBH5(α-ketoglutarate dependent dioxygenase alkb family homolog 5)mRNA levels were lower in the PTBD group than in the ERBD group and significantly correlated with the m6A level of Nanog.ALKBH5 knockdown led to an increase in the m6A level of Nanog,while ALKBH5 overexpression decreased the m6A level of Nanog.Dual-luciferase activity assays demonstrated that ALKBH5 knockdown significantly enhanced luciferase activity,whereas ALKBH5 overexpression reduced it.Further studies confirmed that ALKBH5 knockdown upregulated both the mRNA and protein levels of Nanog,whereas overexpressing ALKBH5 downregulated them.ALKBH5 mediated the demethylation modification of Nanog mRNA,and the lower levels of ALKBH5 expression in the PTBD group promoted Nanog's m6A modification.Overexpressing ALKBH5 decreased tumorsphere growth,while ALKBH5 knockdown increased it,which was subsequently reduced by the simultaneous Nanog knockdown again.In sum,tumor cells in PTBD and ERBD drainage bile from hilar cholangiocar-cinoma patients exhibited tumorigenicity.Compared to the ERBD group,tumor cells in PTBD bile with lower ALKBH5 expression levels enhanced Nanog's m6A modification to upregulate Nanog expression levels,resulting in stronger tumorigenicity.These findings are significant for elucidating propensity to tumor implantation metastasis from PTBD drainage.

Objective To explore feasibility of 3D metal printing technology combined with virtual design proximal clavicle anatomical plate.Methods A 52-year-old male healthy volunteer was retrospectively selected to design proximal clavicle anatomical plate system by using Mimics15.01,NX12.0 and other software.STL data were input into 3D printer to print 1∶1 clavicle model and proximal clavicle anatomical plate.The fit of the plate was tested in vitro and the accuracy of screw position was evaluated by imaging.Printing time of model,nail path design and fabrication time of the anatomical plate at proximal clavicle were recorded.Results The 3D metal printing proximal clavicle anatomical plate fitted well to clavicle model,orienta-tion of proximal clavicle locking screw was accurate,and X-ray and CT scan showed the screw position was good.Printing time of model,the time of nail path design,and the time of making anatomical plate of proximal clavicle were 120,15 and 300 min respectively.Conclusion The proximal clavicular anatomical plate system based on 3D metal printing technology could achieve good lamination of proximal clavicular fracture plate and precise screw placement,providing a new and accurate surgical method for the treatment of the proximal clavicular fracture.

Objective To explore establishment and finite element analysis of personalized proximal clavicular anatomical plate screw fixation model.Methods A 40-year-old male healthy volunteer was selected and the finite element analysis modules of 3D reconstruction software Mimics 15.01,Hypermesh 2019 and Abaqus 2020 were used.The finite element model of anatomic plate at the proximal clavicle was established,and a vertical load of 250 N was applied to the distal end of long axis of clavicle about 15 mm,then the overall structure,plate and screw displacement cloud image,Mises stress distribution were ob-served.Results The displacement distribution of the overall structure shows the maximum displacement was distributed on the distal clavicle.Under the four conditions of normal upper limb weight,longitudinal clavicle fracture,oblique fracture and shoulder impact violence during fall,longitudinal clavicle fracture and oblique fracture,the maximum displacement were 1.04 mm,1.03 mm,1.35 mm and 1.33 mm,respectively.The displacement cloud map of titanium alloy steel plate showed the largest displacement was distributed near the distal clavicular bone,and the maximum displacement were 0.89 mm,0.88 mm,1.10 mm and 1.09 mm,respectively.The displacement cloud map of titanium alloy screw showed the largest displacement was distribut-ed at the root of the distal screw,and the maximum displacement were 0.88 mm,0.87 mm,1.08 mm and 1.06 mm,respectively.Mises stress distribution showed the maximum stress was mainly distributed on titanium alloy plates and screws,and the stress on the clavicle was very small.Mises stress distribution cloud showed the maximum Mises stress was distributed at the second row of screw holes near the clavicle,and the maximum Mises stress were 673.1,678.1,648.5,654.4 MPa,respectively.The maximum stresses of titanium alloy screws were 414.5,417.4,415.8 and 419.7 MPa,respectively.Conclusion The biomechan-ical changes of personalized proximal clavicular anatomical plates are demonstrated by using 3D finite element method to pro-vide biomechanical data for personalized proximal clavicular anatomical plates.