1.Comparison of clinical efficiency between neuroendoscope-assisted evacuation and navigation-assisted puncture in treating thalamic hemorrhage breaking into the ventricle
Yonghui HUANG ; Yang GAO ; Chen LI ; Puyuan ZHAO ; Tian HUAI ; Rujiang BAI ; Xuefu WANG
Chinese Journal of Clinical Medicine 2026;33(1):108-112
Objective To compare the clinical efficacy of neuroendoscope-assisted evacuation and navigation-assisted puncture drainage in treating thalamic hemorrhage breaking into the ventricle. Methods A retrospective analysis was conducted on the clinical data of 93 patients with thalamic hemorrhage breaking into the ventricle at Taihe Hospital of Wannan Medical College between January 2022 and February 2024. The patients received neuroendoscope-assisted removal of thalamic hematoma combined with contralateral extraventricular drainage (n=44, neuroendoscope group) and navigation-assisted thalamic hematoma puncture drainage combined with contralateral extraventricular drainage (n=49, navigation group), respectively. The treatment efficacy, surgical situation, and prognosis between the two groups were compared. Results The neuroendoscope group had longer operation duration, more intraoperative blood loss, higher hospitalization costs than the navigation group (P<0.05). The neuroendoscope group had higher hematoma clearance rate 3rd after surgery and shorter length of stay than the navigation group (P<0.05). There was no significant difference in the incidence of intracranial infection after surgery between the two groups. The neuroendoscope group had higher Glasgow coma scale (GCS) score at 1 week after surgery and Glasgow outcome scale (GOS) score at 3 months after surgery (P<0.01). Conclusions Compared with navigation-assisted puncture, neuroendoscope-assisted evacuation can improve the thalamic hemorrhage clearance rate, shorten the length of stay, and improve the prognosis of patients.
2.Current Status and Prospects of Research on Traditional Chinese Medicine Prevention and Treatment for Gastric Precancerous Lesions
Haiyan BAI ; Tai ZHANG ; Ping WANG ; Lin LIU ; Weichao XU ; Yaxin TIAN ; Lanshuo HU ; Qian YANG ; Xudong TANG
Journal of Traditional Chinese Medicine 2026;67(4):410-415
Traditional Chinese medicine (TCM), through its multi-target and systematic regulatory effects, has demonstrated unique advantages in the treatment of gastric precancerous lesions (GPL). At present, TCM theoretical research on GPL is mainly reflected in three aspects, the integration of macroscopic syndrome differentiation, the inflammation-carcinoma transformation mechanism, as well as the systematization and scientization of theoretical inheritance from famous TCM practitioners. High-quality evidence-based research findings serve as the foundation for clinical practice guidelines on GPL, and TCM has gained international academic recognition in the field of GPL prevention and treatment. Research on TCM mechanisms has yielded a series of important outcomes in the aspects of signaling pathways, gene expression regulation, cellular epigenetics, histone modification, and intestinal microecology. It is proposed that future research on GPL should focus on four key directions, establishing multi-omics data, exploring targeted intervention strategies on key regulatory nodes, advancing the standardization process of integrated traditional Chinese and western medicine prevention and treatment technologies, and constructing stratified screening and intervention platforms. The in-depth integration of TCM microcosmic mechanism of action with its macroscopic syndrome differentiation and treatment system, coupled with interdisciplinary research, will provide valuable references for the clinical treatment and scientific research of GPL.
3.Characteristics and influencing factors of postoperative weight change in patients with esophageal cancer: A prospective longitudinal study
Chengxiang LI ; Yang YANG ; Tian ZHANG ; Ruonan XIE ; Xin JIANG ; Yingjie LENG ; Zhuomiao NIE ; Guorong WANG
Chinese Journal of Clinical Thoracic and Cardiovascular Surgery 2026;33(02):267-274
Objective To longitudinally investigate the characteristics of postoperative weight changes in patients with esophageal cancer and analyze its influencing factors, which can provide certain guidance for nutritional intervention in patients with esophageal cancer. Methods Patients with esophageal cancer who underwent surgical treatment at the Sichuan Cancer Hospital from December 2020 to February 2022 were prospectively included. The general information questionnaire and body composition analyzer were used to longitudinally investigate the patients’ weight and body composition before surgery (T0), 1 month after surgery (T1), 3 months after surgery (T2) and 6 months after surgery (T3), and the change characteristics were analyzed. The generalized estimating equation was used to analyze the influencing factors for postoperative weight changes in patients with esophageal cancer. Results A total of 130 patients were enrolled, including 110 males and 20 females, aged 42-79 (63.33±8.16) years. The weight and body composition of patients with esophageal cancer showed a continuous slow downward trend within 6 months after surgery. The weight loss rate of patients at 1, 3, and 6 months after surgery was 5.10%, 7.76%, and 9.86%, respectively. The analysis results of the influencing factors for postoperative weight showed that patients with the following characteristics had more weight loss: female (β=−7.703, P=0.001), ≥60 years (β=−3.657, P=0.010), smoking (β=4.622, P=0.010), low tumor differentiation degree (β=4.314, P=0.039), and high frequency of eating (β=−3.400, P=0.008). Conclusion Weight loss is an important health problem for patients with esophageal cancer after surgery, and patients have a continuous downward trend in weight within 6 months after surgery. Medical staff should pay special attention to the patients who are female, ≥60 years, having smoking history and low tumor differentiation degree.
4.Protective effect and mechanism of chikusetsu saponin Ⅳa on the kidney in diabetic nephropathy rats
Yongli WANG ; Hai CHEN ; Xiaofang TIAN ; Xuechun WANG ; Liying YUAN ; Dan LIU ; Zhongfa LI ; Yanfang MENG ; Xiuyong YANG
China Pharmacy 2026;37(7):908-913
OBJECTIVE To study the protective effect and potential mechanism of chikusetsu saponin Ⅳ a (chsⅣ) on renal function in diabetic nephropathy (DN) model rats. METHODS DN rat model was established by high-fat diet combined with streptozotocin injection. Thirty-six model rats were randomly divided into model group (i.g. administration of normal saline, high-fat diet), chsⅣ low-dose and high-dose groups (i.g. administration of 90, 180 mg/kg chsⅣ, high-fat diet), with 12 rats in each group. Additionally, 10 normal rats were set as the control group (i.g. administration of normal saline, regular diet). From the 5th to the 12th week after streptozotocin injection, they were given intragastric administration of relevant drug or normal saline, once a day. After the last medication, the levels of fasting blood glucose, fasting insulin, blood urea nitrogen, serum creatinine and urine protein as well as the levels of reduced glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) in renal tissues were measured. Additionally, the insulin resistance index was calculated. Hematoxylin-eosin, periodic acid-Schiff, and Masson staining techniques were employed to examine the histopathological alterations in the renal tissue. The expressions of Notch signaling pathway-related proteins in renal tissue were detected by immunohistochemical staining and Western blot methods. RESULTS Compared with model group, the histomorphological of renal tissues in the chsⅣ low- and high-dose groups were significantly improved, with significant decreases in renal histological scores, mesangial expansion index, and glomerulosclerosis scores ( P <0.05); the levels of fasting blood glucose, fasting insulin, blood urea nitrogen, serum creatinine, urine protein and homeostasis model assessment for insulin resistance, as well as MDA content, the expression levels of Notch1, Notch intracellular domain, hairy and enhancer of Split 1 and Delta-like protein 1 in renal tissue were all significantly decreased ( P <0.05). The levels of GSH and SOD in renal tissue were significantly elevated ( P <0.05). Moreover, the improvement in these indicators was significantly more pronounced in the chsⅣ high-dose group compared to the chsⅣ low-dose group ( P <0.05). CONCLUSIONS ChsⅣ can ameliorate renal pathological damage and functional impairment in DN rats. Its underlying mechanisms include restoration of glucose homeostasis and insulin sensitivity, attenuation of renal oxidative stress, and suppression of aberrant Notch signaling pathway activation.
5.Ameliorative Effect of Wendantang Combined with Danshenyin and Dushentang on Ischemic Heart Disease with Phlegm-stasis Syndrome in Mice Based on Circulating Monocytes
Fenghe YANG ; Ziqi TIAN ; Zhiqian SONG ; Shitao PENG ; Wenjie LU ; Tao LIN ; Chun WANG ; Zhangchi NING
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):22-32
ObjectiveTo investigate the ameliorative effect of Wendantang combined with Danshenyin and Dushentang (WDD) on mice with ischemic heart disease (IHD) presenting phlegm-stasis syndrome based on the inflammatory phenotype and differentiation of circulating monocytes. MethodsA model of IHD with phlegm-stasis syndrome was established using left anterior descending coronary artery ligation supplemented with a high-fat diet. Eighty model mice were randomly assigned to the model group, WDD low-dose group (WDD-L), WDD medium-dose group (WDD-M), WDD high-dose group (WDD-H), and atorvastatin calcium tablet group, with 16 mice in each group. An additional 16 C57BL/6J mice were designated as the sham-operation group. The WDD groups received intragastric administration at doses of 8.91, 17.81, 35.62 g·kg-1, and the atorvastatin calcium tablet group received the corresponding drug at 1.3 mg·kg-1, twice daily. The sham-operation and model groups were given the same volume of pure water by gavage each day. After 5 consecutive weeks of administration, the cardiac index was calculated. Cardiac function was assessed by echocardiography. Myocardial histopathology was examined by hematoxylin-eosin (HE) staining. Serum N-terminal pro-B-type natriuretic peptide (pro-BNP) content was measured by enzyme-linked immunosorbent assay (ELISA). Hemorheological parameters were analyzed using an automated hemorheology analyzer. Serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were determined using an automated biochemical analyzer. Changes in circulating monocytes were detected by flow cytometry. Mouse bone marrow mononuclear cells were isolated in vitro and divided into blank group, model serum group, WDD-L drug-containing serum group, WDD-M drug-containing serum group, and WDD-H drug-containing serum group. CD36 expression and macrophage differentiation in each group were assessed by flow cytometry. The mechanism by which WDD mediates circulating monocyte differentiation was further explored using CD36 knockdown/overexpression RAW264.7 cell lines. ResultsCompared with the sham-operation group, the model group showed a significantly increased cardiac index (P0.01), significantly decreased fractional shortening (FS) (P0.01), and significantly increased left ventricular end-diastolic internal diameter (LVDD) and left ventricular end-systolic internal diameter (LVDS) (P0.01). Cardiomyocytes exhibited marked deformation and necrosis with inflammatory cell infiltration. Serum pro-BNP levels were significantly elevated (P0.01), and whole-blood viscosity (BV) at high, medium, and low shear rates was significantly increased (P0.01). Compared with the model group, the WDD groups showed significantly reduced cardiac index (P0.05, P0.01), significantly increased FS (P0.05, P0.01), significantly decreased LVDD and LVDS (P0.01), markedly improved cardiomyocyte morphology, significantly reduced inflammatory infiltration, significantly decreased serum pro-BNP levels (P0.01), and significantly decreased BV at high, medium, and low shear rates (P0.01), with the most pronounced improvement observed in the WDD-M group. Compared with the sham-operation group, TC, TG, and LDL levels were significantly increased in the model group (P0.05, P0.01), while HDL levels were significantly decreased (P0.05). After WDD-H treatment, TC, TG, and LDL levels were significantly reduced and HDL levels were significantly increased in mice (P0.05, P0.01). Compared with the sham-operation group, classical monocytes in blood and bone marrow and intermediate monocytes in blood were significantly increased in the model group (P0.01), whereas intermediate monocytes in bone marrow and non-classical monocytes in blood were significantly decreased (P0.01). After WDD administration, all circulating monocyte subsets in blood and bone marrow were significantly alleviated (P0.05, P0.01), with the WDD-M group showing the optimal effect. In vitro, compared with the blank group, CD36 expression on bone marrow monocytes and the proportion of differentiated macrophages were significantly increased in the model serum group (P0.01), and CD36 expression was significantly upregulated on RAW264.7 cells (P0.01). Compared with the model serum group, all drug-containing serum groups exhibited significantly reduced CD36 expression on bone marrow monocytes and significantly reduced macrophage differentiation (P0.01). WDD downregulated CD36 expression in both CD36 knockdown and overexpression RAW264.7 cell lines (P0.05, P0.01), with the strongest regulatory effect observed in the WDD-M drug-containing serum group. ConclusionWDD can significantly improve the manifestations of phlegm-stasis syndrome in IHD mice and reduce the proportion of classical circulating monocytes. Its mechanism may be related to the inhibition of CD36 expression on classical circulating monocytes.
6.Ameliorative Effect of Wendantang Combined with Danshenyin and Dushentang on Ischemic Heart Disease with Phlegm-stasis Syndrome in Mice Based on Circulating Monocytes
Fenghe YANG ; Ziqi TIAN ; Zhiqian SONG ; Shitao PENG ; Wenjie LU ; Tao LIN ; Chun WANG ; Zhangchi NING
Chinese Journal of Experimental Traditional Medical Formulae 2026;32(3):22-32
ObjectiveTo investigate the ameliorative effect of Wendantang combined with Danshenyin and Dushentang (WDD) on mice with ischemic heart disease (IHD) presenting phlegm-stasis syndrome based on the inflammatory phenotype and differentiation of circulating monocytes. MethodsA model of IHD with phlegm-stasis syndrome was established using left anterior descending coronary artery ligation supplemented with a high-fat diet. Eighty model mice were randomly assigned to the model group, WDD low-dose group (WDD-L), WDD medium-dose group (WDD-M), WDD high-dose group (WDD-H), and atorvastatin calcium tablet group, with 16 mice in each group. An additional 16 C57BL/6J mice were designated as the sham-operation group. The WDD groups received intragastric administration at doses of 8.91, 17.81, 35.62 g·kg-1, and the atorvastatin calcium tablet group received the corresponding drug at 1.3 mg·kg-1, twice daily. The sham-operation and model groups were given the same volume of pure water by gavage each day. After 5 consecutive weeks of administration, the cardiac index was calculated. Cardiac function was assessed by echocardiography. Myocardial histopathology was examined by hematoxylin-eosin (HE) staining. Serum N-terminal pro-B-type natriuretic peptide (pro-BNP) content was measured by enzyme-linked immunosorbent assay (ELISA). Hemorheological parameters were analyzed using an automated hemorheology analyzer. Serum levels of total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL), and high-density lipoprotein (HDL) were determined using an automated biochemical analyzer. Changes in circulating monocytes were detected by flow cytometry. Mouse bone marrow mononuclear cells were isolated in vitro and divided into blank group, model serum group, WDD-L drug-containing serum group, WDD-M drug-containing serum group, and WDD-H drug-containing serum group. CD36 expression and macrophage differentiation in each group were assessed by flow cytometry. The mechanism by which WDD mediates circulating monocyte differentiation was further explored using CD36 knockdown/overexpression RAW264.7 cell lines. ResultsCompared with the sham-operation group, the model group showed a significantly increased cardiac index (P<0.01), significantly decreased fractional shortening (FS) (P<0.01), and significantly increased left ventricular end-diastolic internal diameter (LVDD) and left ventricular end-systolic internal diameter (LVDS) (P<0.01). Cardiomyocytes exhibited marked deformation and necrosis with inflammatory cell infiltration. Serum pro-BNP levels were significantly elevated (P<0.01), and whole-blood viscosity (BV) at high, medium, and low shear rates was significantly increased (P<0.01). Compared with the model group, the WDD groups showed significantly reduced cardiac index (P<0.05, P<0.01), significantly increased FS (P<0.05, P<0.01), significantly decreased LVDD and LVDS (P<0.01), markedly improved cardiomyocyte morphology, significantly reduced inflammatory infiltration, significantly decreased serum pro-BNP levels (P<0.01), and significantly decreased BV at high, medium, and low shear rates (P<0.01), with the most pronounced improvement observed in the WDD-M group. Compared with the sham-operation group, TC, TG, and LDL levels were significantly increased in the model group (P<0.05, P<0.01), while HDL levels were significantly decreased (P<0.05). After WDD-H treatment, TC, TG, and LDL levels were significantly reduced and HDL levels were significantly increased in mice (P<0.05, P<0.01). Compared with the sham-operation group, classical monocytes in blood and bone marrow and intermediate monocytes in blood were significantly increased in the model group (P<0.01), whereas intermediate monocytes in bone marrow and non-classical monocytes in blood were significantly decreased (P<0.01). After WDD administration, all circulating monocyte subsets in blood and bone marrow were significantly alleviated (P<0.05, P<0.01), with the WDD-M group showing the optimal effect. In vitro, compared with the blank group, CD36 expression on bone marrow monocytes and the proportion of differentiated macrophages were significantly increased in the model serum group (P<0.01), and CD36 expression was significantly upregulated on RAW264.7 cells (P<0.01). Compared with the model serum group, all drug-containing serum groups exhibited significantly reduced CD36 expression on bone marrow monocytes and significantly reduced macrophage differentiation (P<0.01). WDD downregulated CD36 expression in both CD36 knockdown and overexpression RAW264.7 cell lines (P<0.05, P<0.01), with the strongest regulatory effect observed in the WDD-M drug-containing serum group. ConclusionWDD can significantly improve the manifestations of phlegm-stasis syndrome in IHD mice and reduce the proportion of classical circulating monocytes. Its mechanism may be related to the inhibition of CD36 expression on classical circulating monocytes.
7.Pathogenic Mechanisms of Spleen Deficiency-Phlegm Dampness in Obesity and Traditional Chinese Medicine Prevention and Treatment Strategies:from the Perspective of Immune Inflammation
Yumei LI ; Peng XU ; Xiaowan WANG ; Shudong CHEN ; Le YANG ; Lihua HUANG ; Chuang LI ; Qinchi HE ; Xiangxi ZENG ; Juanjuan WANG ; Wei MAO ; Ruimin TIAN
Journal of Traditional Chinese Medicine 2026;67(1):31-37
Based on spleen deficiency-phlegm dampness as the core pathogenesis of obesity, and integrating recent advances in modern medicine regarding the key role of immune inflammation in obesity, this paper proposes a multidimensional pathogenic network of "obesity-spleen deficiency-phlegm dampness-immune imbalance". Various traditional Chinese medicine (TCM) herbs that strengthen the spleen, regulate qi, and resolve phlegm and dampness can treat obesity by improving spleen-stomach transport and transformation, promoting water-damp metabolism, and regulating immune homeostasis. This highlights immune inflammation as an important entry point to elucidate the TCM concepts of "spleen deficiency-phlegm dampness" and the therapeutic principle of "strengthening the spleen and eliminating dampness to treat obesity". By systematically analyzing the intrinsic connection between "spleen deficiency generating dampness, internal accumulation of phlegm dampness" and immune dysregulation in obesity, this paper aims to provide theoretical support for TCM treatment of obesity based on dampness.
8.MRI findings of spinal cord atrophy after spinal cord injury in children and their injury level
Yingxin ZHANG ; Genlin LIU ; Di CHEN ; Hongxia ZHANG ; Yifan TIAN ; Yiji WANG ; Yang JING ; Ruidong CHENG ; Shaomin ZHANG ; Jiafeng YAO ; Bo SUN ; Xiaomeng SUN
Chinese Journal of Rehabilitation Theory and Practice 2026;32(4):387-392
ObjectiveTo delineate imaging findings using an imaging platform and investigate the correlation between MRI characteristics of spinal cord atrophy and clinical diagnosis in children with spinal cord injury (SCI). MethodsImaging data of 150 children with SCI admitted to Beijing Bo'ai Hospital, China Rehabilitation Research Center, from January, 2002 to March, 2024 were collected and imported into the imaging platform. The anteroposterior and transverse diameters of the middle part of the spinal cord at the cross-section with the most severe atrophy were measured, and the relevant indicators of the previous normal spinal cord segment were measured as controls; the radiomic features were extracted. Clinical data of the children including gender, age, cause of injury, sensory level, motor level, spinal cord injury level, injury severity and disease course were collected. ResultsSpinal cord atrophy was identified in 81 cases (54%), among which 78 cases (96%) were American Spinal Injury Association Impairment Scale (AIS) grade A and 3 cases (4%) were AIS grade C. The upper boundary of the spinal cord atrophy site strongly correlated with the injury level, motor level and sensory level (r > 0.8, P < 0.001). ConclusionMore than half of children with SCI may develop secondary spinal cord atrophy, the vast majority of whom suffer from complete spinal cord injury; the upper boundary of spinal cord atrophy is correlated with the injury level.
9.Fibroblast Growth Factors in Parkinson’s Disease: Multi-target Neuroprotective Mechanisms Involving Neuroinflammation, Cellular Stress, and Ferroptosis
Hui WANG ; Zi-Gui ZHOU ; Teng-Teng HAN ; Chang-Zhi YANG ; Xue-Wen TIAN
Progress in Biochemistry and Biophysics 2026;53(4):855-874
Parkinson’s disease (PD) is a progressive neurodegenerative disorder characterized by the selective loss of dopaminergic neurons in the substantia nigra pars compacta and the pathological accumulation ofα‑synuclein. Although extensive progress has been made in elucidating its pathogenesis, current therapeutic approaches remain largely symptomatic, and effective disease-modifying treatments are still unavailable. Increasing evidence indicates that PD is driven by the interaction of multiple pathological processes, including neuroinflammation, iron homeostasis dysregulation and ferroptosis, endoplasmic reticulum (ER) stress, mitochondrial dysfunction, oxidative stress, and impaired protein homeostasis, which together contribute to neuronal vulnerability and degeneration. Fibroblast growth factors (FGFs) comprise a family of 22 ligands that play important roles in neural development, stress responses, metabolic regulation, and the maintenance of nervous system homeostasis. Recent studies have shown that several FGF family members, such as FGF1, FGF2, FGF9, and FGF21, exert neuroprotective effects in cellular and animal models of PD. These effects include the regulation of inflammatory responses, oxidative stress, iron homeostasis, cellular stress adaptation, and neuronal survival. Compared with therapeutic strategies targeting a single pathogenic pathway, FGFs appear to influence multiple disease-related processes, suggesting their potential relevance to the complex pathophysiology of PD. Experimental evidence indicates that altered FGF signaling may contribute to dopaminergic neuron dysfunction through the coordinated regulation of several interconnected mechanisms. FGFs have been reported to modulate neuroinflammation by affecting the activation of microglia and astrocytes, thereby influencing the inflammatory environment in the central nervous system. In addition, FGFs are involved in the regulation of iron homeostasis and ferroptosis, partly through antioxidant signaling pathways associated with NRF2, SLC7A11, and GPX4. Moreover, FGFs can alleviate ER stress and mitochondrial dysfunction by activating intracellular signaling pathways such as PI3K/AKT, AMPK-PGC-1α, as well as SIRT1-dependent programs, which support cellular energy metabolism and redox balance. Recent advances in single-cell and spatial transcriptomic studies further suggest that FGF signaling is not limited to neuron-intrinsic mechanisms but also involves interactions among different glial cell types. Altered FGF ligand-receptor communication between astrocytes and oligodendrocytes has been observed in PD models and is associated with increased susceptibility of dopaminergic neurons to oxidative stress and ferroptosis. These findings indicate that the biological effects of FGFs are influenced by cell type and disease stage and may vary under different pathological conditions. In this review, we summarize recent progress in understanding the roles of FGF family members in PD, with a focus on their involvement in iron homeostasis dysregulation and ferroptosis, neuroinflammation, cellular stress responses, and neuronal protection and regeneration. By integrating current evidence, this review aims to provide a clearer understanding of how FGFs participate in PD pathogenesis and to offer a theoretical basis for future studies exploring their potential value in disease-modifying therapeutic strategies.
10.Compact Fundus Imaging System Using Shack-Hartmann Wavefront Sensing for High-speed Auto-focus
Zhe-Kai LIN ; Long CHEN ; Geng-Yong ZHENG ; Jin-Tian HUANG ; Jia-Xin DONG ; Shang-Pan YANG ; Wen-Zheng DING ; Ding-An HAN ; Xue-Hua WANG ; Ya-Guang ZENG
Progress in Biochemistry and Biophysics 2026;53(4):1076-1086
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.

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