1.A low-dose CT reconstruction method using sub-pixel anisotropic diffusion.
Shizhou TANG ; Ruolan SU ; Shuting LI ; Zhenzhen LAI ; Jinhong HUANG ; Shanzhou NIU
Journal of Southern Medical University 2025;45(1):162-169
OBJECTIVES:
We present a new low-dose CT reconstruction method using sub-pixel and anisotropic diffusion.
METHODS:
The sub-pixel intensity values and their second-order differences were obtained using linear interpolation techniques, and the new gradient information was then embedded into an anisotropic diffusion process, which was introduced into a penalty-weighted least squares model to reduce the noise in low-dose CT projection data. The high-quality CT image was finally reconstructed using the classical filtered back-projection (FBP) algorithm from the estimated data.
RESULTS:
In the Shepp-Logan phantom experiments, the structural similarity (SSIM) index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 28.13%, 5.49%, and 0.91%, the feature similarity (FSIM) index was increased by 21.08%, 1.78%, and 1.36%, and the root mean square error (RMSE) was reduced by 69.59%, 18.96%, and 3.90%, respectively. In the digital XCAT phantom experiments, the SSIM index of the CT image reconstructed by the proposed algorithm, as compared with FBP, PWLS-Gibbs and PWLS-TV algorithms, was increased by 14.24%, 1.43% and 7.89%, the FSIM index was increased by 9.61%, 1.78% and 5.66%, and the RMSE was reduced by 26.88%, 9.41% and 18.39%, respectively. In clinical experiments, the SSIM index of the image reconstructed using the proposed algorithm was increased by 19.24%, 15.63% and 3.68%, the FSIM index was increased by 4.30%, 2.92% and 0.43%, and the RMSE was reduced by 44.60%, 36.84% and 15.22% in comparison with FBP, PWLS-Gibbs and PWLS-TV algorithms, respectively.
CONCLUSIONS
The proposed method can effectively reduce the noises and artifacts while maintaining the structural details in low-dose CT images.
Tomography, X-Ray Computed/methods*
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Algorithms
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Phantoms, Imaging
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Anisotropy
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Image Processing, Computer-Assisted/methods*
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Humans
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Radiation Dosage
2.Expert consensus on cryoablation therapy of oral mucosal melanoma
Guoxin REN ; Moyi SUN ; Zhangui TANG ; Longjiang LI ; Jian MENG ; Zhijun SUN ; Shaoyan LIU ; Yue HE ; Wei SHANG ; Gang LI ; Jie ZHNAG ; Heming WU ; Yi LI ; Shaohui HUANG ; Shizhou ZHANG ; Zhongcheng GONG ; Jun WANG ; Anxun WANG ; Zhiyong LI ; Zhiquan HUNAG ; Tong SU ; Jichen LI ; Kai YANG ; Weizhong LI ; Weihong XIE ; Qing XI ; Ke ZHAO ; Yunze XUAN ; Li HUANG ; Chuanzheng SUN ; Bing HAN ; Yanping CHEN ; Wenge CHEN ; Yunteng WU ; Dongliang WEI ; Wei GUO
Journal of Practical Stomatology 2024;40(2):149-155
Cryoablation therapy with explicit anti-tumor mechanisms and histopathological manifestations has a long history.A large number of clinical practice has shown that cryoablation therapy is safe and effective,making it an ideal tumor treatment method in theory.Previously,its efficacy and clinical application were constrained by the limitations of refrigerants and refrigeration equipment.With the development of the new generation of cryoablation equipment represented by argon helium knives,significant progress has been made in refrigeration efficien-cy,ablation range,and precise temperature measurement,greatly promoting the progression of tumor cryoablation technology.This consensus systematically summarizes the mechanism of cryoablation technology,indications for oral mucosal melanoma(OMM)cryotherapy,clinical treatment process,adverse reactions and management,cryotherapy combination therapy,etc.,aiming to provide reference for carrying out the standardized cryoablation therapy of OMM.
3.Low-dose CT reconstruction based on high-dimensional partial differential equation projection recovery
Shanzhou NIU ; Shizhou TANG ; Shuyan HUANG ; Lijing LIANG ; Shuo LI ; Hanming LIU
Journal of Southern Medical University 2024;44(4):682-688
Objective We propose a low-dose CT reconstruction method using partial differential equation (PDE) denoising under high-dimensional constraints. Methods The projection data were mapped into a high-dimensional space to construct a high-dimensional representation of the data, which were updated by moving the points in the high-dimensional space. The data were denoised using partial differential equations and the CT image was reconstructed using the FBP algorithm. Results Compared with those by FBP, PWLS-QM and TGV-WLS methods, the relative root mean square error of the Shepp-Logan image reconstructed by the proposed method were reduced by 68.87%, 50.15% and 27.36%, the structural similarity values were increased by 23.50%, 8.83% and 1.62%, and the feature similarity values were increased by 17.30%, 2.71% and 2.82%, respectively. For clinical image reconstruction, the proposed method, as compared with FBP, PWLS-QM and TGV-WLS methods, resulted in reduction of the relative root mean square error by 42.09%, 31.04%and 21.93%, increased the structural similarity values by 18.33%, 13.45% and 4.63%, and increased the feature similarity values by 3.13%, 1.46% and 1.10%, respectively. Conclusion The new method can effectively reduce the streak artifacts and noises while maintaining the spatial resolution in reconstructed low-dose CT images.
4.Transfer of fibular pedicled bone flap of the proximal great toe to reconstruct the donor site defect in the second toe left by a flap harvesting for reconstruction of interphalangeal joint defects in fingers
Xiang WU ; Songgen PENG ; Haiyan HUANG ; Shengshan LI ; Min LIU ; Shizhou LI ; Songnan LIAO ; Qiaohong GUO ; Jingliang ZHANG
Chinese Journal of Microsurgery 2024;47(3):294-299
Objective:To investigate the clinical efficacy of transfer of a free segment of the proximal second toe interphalangeal joint composite tissue flap in reconstruction of defects of interphalangeal joint of fingers, and simultaneously reconstruct the donor site defect left with the second toe by a transfer of a pedicled bone flap of the fibular proximal great toe.Methods:From December 2020 to April 2023, a total of 9 patients with interphalangeal joint defects of fingers were treated in the Department of Hand Microsurgery of Shunde Heping Surgery Hospital. The patients were 7 males and 2 females, aged 18-55 years old, with an average age of 31 years old. Firstly, transfers of a free segment of the proximal second toe interphalangeal joint composite tissue flap were performed to reconstruct the defects of finger joints. Simultaneously in the surgery, transfers of the fibular pedicled bone flap of the proximal great toe were conducted to reconstruct the donor site defects left in the second toe. Patients were instructed with appropriate postoperative functional exercises. K-wires were removed at 8-12 weeks after surgery. Outpatient visits, telephone and WeChat follow-ups were conducted to evaluate the appearance and functional recovery of the reconstructed interphalangeal joints and donor feet. Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association, Vancouver Scar Scale (VSS) and American Orthopedic Foot and Ankle Society (AOFAS) foot function scoring standards were employed in the evaluation.Results:Postoperative follow-up lasted for 6 to 30 months. All of the 9 interphalangeal joint composite tissue flaps in the fingers survived with complete and good appearance. Function of the reconstructed interphalangeal joints of the fingers recovered well. According to the Evaluation Trial Standards of Upper Limb Partial Functional of Hand Surgery of Chinese Medical Association, the average score achieved 12 points, with 6 patients of excellent, 2 of good and 1 of fair. After surgery, the appearance and function of the donor great toes and second toes all recovered well. The average score of the scars in donor second toe evaluated by VSS was 4 points. All the donor feet were kept with 5 toes, with full, intact and good in appearance. According to the AOFAS foot function scoring standard, the average score achieved 95 points, and were excellent.Conclusion:Application of transfer of free proximal segment of interphalangeal joint composite tissue flap of the second toe in reconstruction of the interphalangeal joint defect of a finger, and simultaneously reconstruct the defect left with the donor second toe with a fibular proximal great toe flap pedicled with bone tissue can achieve good clinical efficacy in reconstruction of the defects of interphalangeal joint of fingers, restore the function of the interphalangeal joint of fingers and the appearance and function of the donor foot.
5.Low-dose CT reconstruction based on high-dimensional partial differential equation projection recovery
Shanzhou NIU ; Shizhou TANG ; Shuyan HUANG ; Lijing LIANG ; Shuo LI ; Hanming LIU
Journal of Southern Medical University 2024;44(4):682-688
Objective We propose a low-dose CT reconstruction method using partial differential equation (PDE) denoising under high-dimensional constraints. Methods The projection data were mapped into a high-dimensional space to construct a high-dimensional representation of the data, which were updated by moving the points in the high-dimensional space. The data were denoised using partial differential equations and the CT image was reconstructed using the FBP algorithm. Results Compared with those by FBP, PWLS-QM and TGV-WLS methods, the relative root mean square error of the Shepp-Logan image reconstructed by the proposed method were reduced by 68.87%, 50.15% and 27.36%, the structural similarity values were increased by 23.50%, 8.83% and 1.62%, and the feature similarity values were increased by 17.30%, 2.71% and 2.82%, respectively. For clinical image reconstruction, the proposed method, as compared with FBP, PWLS-QM and TGV-WLS methods, resulted in reduction of the relative root mean square error by 42.09%, 31.04%and 21.93%, increased the structural similarity values by 18.33%, 13.45% and 4.63%, and increased the feature similarity values by 3.13%, 1.46% and 1.10%, respectively. Conclusion The new method can effectively reduce the streak artifacts and noises while maintaining the spatial resolution in reconstructed low-dose CT images.
6.Investigation of quality attributes of outpatient doctors based on Kano model
Bingwen HE ; Lihua PENG ; Yongpin WU ; Shizhou LI ; Banghui OUYANG ; Renbin HUANG
Chinese Journal of Hospital Administration 2021;37(8):666-670
Objective:To identify the essential quality, expected quality and charm quality of outpatient doctors based on Kano model.Methods:The Kano model quality attribute questionnaire for outpatient doctors was designed from 4 dimensions and 18 indicators of service, quality, safety and cost. 220 outpatients were investigated in a tertiary hospital. The reliability and validity of 212 valid questionnaires were tested and the questionnaire data were analyzed.Results:Both the Cronbach α coefficient and the KMO value were higher than 0.7, which indicated that the reliability and validity were good. Nine of the 18 survey indicators were essential quality, focusing on the quality dimension and service dimension; 4 items were expected quality; 4 items were charm quality, focusing on disease cognition, prevention and drug safety; 1 item was indifferent quality.Conclusions:The essential quality of outpatient doctors is to provide basic and standardized medical services to patients. Studying the quality attribute can provide behavior guidance for outpatient doctors, improve patient satisfaction and quality of outpatient medical services.
7. The special named ankle fractures: the diagnosis and treatment
Yaxing LI ; Yi REN ; Xia TANG ; Yu CHEN ; Shizhou WU ; Wei DENG ; Yun ZHU ; Fuguo HUANG ; Hui ZHANG
Chinese Journal of Orthopaedics 2019;39(21):1344-1356
Due to the complex anatomical structure of ankle and the various mechanisms of ankle injury, manyeponyms and systematic classifications of ankle fracture have been developed in the past centuries. Before the emergence and constant improvement of classifications of ankle fracture, ankle fractures were most commonly named afterthe physicians who first described them. Now,these ankle fracture eponyms are still found in medical literature, textbooks and even mass media. Many special named ankle fractures can be explained by the Lauge-Hansen classification now, and they may have little practical use. However, it is still necessary to summarize and review these ankle fracture eponyms, in order to correct the wrong usage of these and to remember the sages in this field.We reviewed both common and less frequently used ankle fracture eponyms, focusing on imaging features to identify and differentiate these injuries. We also briefly reviewed the mechanism of each injury, associated complications, its diagnosis and treatment.
8.Open reduction and internal fixation combined with Ilizarov joint distraction for treatment of comminuted talar body fractures
Jia LI ; Yaxing LI ; Yu CHEN ; Wei DENG ; Shizhou WU ; Yi REN ; Fuguo HUANG ; Hui ZHANG
Chinese Journal of Orthopaedic Trauma 2017;19(12):1024-1028
Objective To evaluate open reduction and internal fixation (ORIF) combined with Ilizarov joint distraction in the treatment of comminuted talar body fractures.Methods Between July 2010 and May 2016,16 patients with comminuted talar body fracture underwent ORIF followed by ankle joint distraction by Ilizarov external fixator at our department.They were 9 males and 7 females,aged from 17 to 56 years (average,35.6 years).Radiological assessments were conducted by plain radiographs and computed tomography (CT) scans pre-and post-operatively.Clinical outcomes were evaluated according to visual analogue scale (VAS),American Orthopedic Foot and Ankle Society (AOFAS) hindfoot score,the short form (SF)-36 health survey scores and patients' satisfaction.Results Two patients were lost to follow-up.The remaining 14 patients were followed up for an average duration of 33.3 months (from 13 to 52 months).All the fractures united.Superficial wound infection occurred in one case.Eight patients developed post-traumatic osteoarthris;4 patients presented with avascular necrosis.At final follow-ups,the AOFAS scores ranged from 30 to 97 points (mean,69.8 points),the VAS scores from 0 to 6 points (mean,2.5 points),the physical component summary in SF-36 from 18.0 to 55 points (mean,41.7 points),and the mental component summary from 40 to 70 points (mean,54.1 points).Two patients reported strong satisfaction,5 satisfaction,4 moderate satisfaction,and 3 dissatisfaction.Conclusion For comminuted talar body fractures,ORIF combined with Ilizarov joint distraction is a new and effective treatment which can not only provide adequate fixation strength but also reduce the incidence of post-traumatic osteoarthris or avascular necrosis.
9.Findings from multifocal electroretinography of posterior uveitis in Behcet's disease
Guangwei LUO ; Feng, WEN ; Futian, JIANG ; Shizhou, HUANG ; Shixian, LONG ; Caijiao, LIU ; Tianqin, GUAN
Chinese Ophthalmic Research 2010;28(3):257-260
Background Behcet's disease is a refractory panuveitis with high blindness rate.Multifocal electroretinography (mfERG) is a useful tool for the evaluation of the function of the posterior retina.ObjectiveThe aim of this study is to assess the characteristics of Behcet's disease using the mfERG.Methods mfERG was recorded in 68 eyes of 39 cases with active stage of Behcet's disease.All of the patients were diagnosed based on the Standard of International Study Group for Behcet's Disease and assigned to the cystoid macular edema (CME) group and the diffuse macular edema (DME) group after assessment by fundus fluorescein angiography (FFA).Seventeen normal subjects were used as controls.Oral informed consent was obtained from all of the subjects prior to this trial.mfERG recording followed the ISCEV Guidelines for Clinical Multifocal Electroretinography (2007 edition).The response density and latency of P1 and N1 waves in 6 rings were analyzed and compared.Results The amplitudes of N_1 waves from rings 1 through 6 and N1 wave from rings 1 through 5 were significantly declined in patients with Behcet's disease compared with normal control (P<0.01).All of the latencies of P_1 waves from rings 1 through 6 were insignificantly shortened in patients with Behcet's disease compared with normal control (P>0.05).The amplitudes of P_1 and N_1 waves from rings 1 through 6 in diffuse macular edema group were considerably lower than those in the cystoid macular edema group (P<0.05,P<0.01).A test of visual acuity showed a negative correlation to the amplitude and latency of N_1 wave (r=-0.36,-0.37,P<0.05 ) and a positive correlation with the amplitude of N1 wave (r=0.43,P<0.05) in the DME group.In the CME group,a test of visual acuity presented a negative correlation to the amplitude and latency of N1 wave and latency of P1 (r=-0.41,-0.35,-0.40,P<0.05 ) and a positive correlation with the amplitude of P1 wave (r=0.48,P<0.05).Conclusion mfEGR demonstrates that retinal electro-activity is abnormal in eyes with Behcet's disease.The distinct functional disorder is situated around the fovea.
10.Effect of experimental scotoma on multifocal visual evoked potential
Xiaopeng HU ; Shizhou HUANG ; Futian JIANG ; Shixian LONG ; Jiongji LIANG ; Dezheng WU ; Lezheng WU
Journal of Third Military Medical University 2003;0(07):-
Objective To investigate the influence of experimental scotoma on multifocal visual evoked potential (mf-VEP). Methods The mf-VEP of 10 healthy individuals (20 eyes) was measured with VERIS Science 4.0. Every eye was measured for 3 times. The right eye was measured with full field stimulation and upper hemi-field or lower hemi-field masked. The left eye was measured with full field stimulation and central three-rings area or lower nasal field masked. The first slice responses of the second order in different field were analyzed and compared by VERIS software. Results The mf-VEP in masked area was undetectable or obviously decreased in all subjects. In most unmasked field, the amplitudes of mf-VEP were not changed, except that in some place decreased slightly with statistically significant difference in comparison to the full field stimulation mode. Conclusion mf-VEP is influenced with experimental scotoma. The mf-VEP changes are consistent with the visual field masked.

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