Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 30
Filter
1.
Quant Imaging Med Surg ; 14(4): 2788-2799, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38617180

ABSTRACT

Background: Color Doppler ultrasonography (CDUS) is feasible to detect arteriovenous fistula (AVF) dysfunction in hemodialysis patients but is not sufficient to map the structure of fistula required for interventions. This study is designed to evaluate the diagnostic accuracy of three-dimensional time-of-flight magnetic resonance angiography (TOF-MRA) at 3.0T versus CDUS for AVF dysfunction, by using digital subtraction angiography (DSA) as reference. Methods: This prospective study enrolled 68 consecutive patients with dysfunctional AVF who underwent both CDUS and TOF-MRA at Shanghai Sixth People's Hospital affiliated to Shanghai Jiao Tong University School of Medicine. The analysis of the dysfunctional AVFs was divided into three regions: the feeding artery, fistula and draining veins. In the whole- and per-regional-based analyses, two observers who were blinded to the clinical and DSA results independently analyzed all CDUS and TOF-MRA datasets. The image quality and stenosis severity of the lesions on TOF-MRA were evaluated. A receiver operating characteristic curve was applied to analyze the detection of AVF dysfunction with TOF-MRA. Results: A total of 204 vessel regions were evaluated. The whole-region-based image quality of TOF-MRA was poorer in patients with a total occlusion (1.8±0.8) than in those with stenosis (2.7±0.6, P<0.001). In the whole-region analyses, TOF-MRA had higher sensitivity [99.1% (94.6-100.0%) vs. 82.9% (74.6-89.0%), P<0.001] and similar specificity [93.1% (85.0-97.1%) vs. 94.3% (86.5-97.9%), P=0.755] than CDUS. The per-region-based analyses showed that TOF-MRA yielded higher sensitivity [fistula region, 98.1% (88.4-99.9%) vs. 80.8% (67.0-89.9%); P=0.004; draining vein region, 100.0% (92.5-100.0%) vs. 85.0% (72.9-2.5%); P=0.003] and similar specificity [fistula region, 88.2% (62.3-97.8%) vs. 88.2% (62.3-97.9%); P>0.99; draining vein region, 100.0% (59.8-100.0%) vs. 87.5% (46.7-99.3%); P>0.99] than CDUS. Sensitivity and specificity of TOF-MRA were comparable to those of CDUS in feeding artery region. Conclusions: TOF-MRA is a feasible and accurate method to display AVF dysfunction in hemodialysis patients, and this method might fulfill the endovascular treatment planning requirements.

2.
Quant Imaging Med Surg ; 12(6): 3276-3287, 2022 Jun.
Article in English | MEDLINE | ID: mdl-35655831

ABSTRACT

Background: To use adversarial training to increase the generalizability and diagnostic accuracy of deep learning models for prostate cancer diagnosis. Methods: This multicenter study retrospectively included 396 prostate cancer patients who underwent magnetic resonance imaging (development set, 297 patients from Shanghai Jiao Tong University Affiliated Sixth People's Hospital and Eighth People's Hospital; test set, 99 patients from Renmin Hospital of Wuhan University). Two binary classification deep learning models for clinically significant prostate cancer classification [PM1, pretraining Visual Geometry Group network (VGGNet)-16-based model 1; PM2, pretraining residual network (ResNet)-50-based model 2] and two multiclass classification deep learning models for prostate cancer grading (PM3, pretraining VGGNet-16-based model 3; PM4: pretraining ResNet-50-based model 4) were built using apparent diffusion coefficient and T2-weighted images. These models were then retrained with adversarial examples starting from the initial random model parameters (AM1, adversarial training VGGNet-16 model 1; AM2, adversarial training ResNet-50 model 2; AM3, adversarial training VGGNet-16 model 3; AM4, adversarial training ResNet-50 model 4, respectively). To verify whether adversarial training can improve the diagnostic model's effectiveness, we compared the diagnostic performance of the deep learning methods before and after adversarial training. Receiver operating characteristic curve analysis was performed to evaluate significant prostate cancer classification models. Differences in areas under the curve (AUCs) were compared using Delong's tests. The quadratic weighted kappa score was used to verify the PCa grading models. Results: AM1 and AM2 had significantly higher AUCs than PM1 and PM2 in the internal validation dataset (0.84 vs. 0.89 and 0.83 vs. 0.87) and test dataset (0.73 vs. 0.86 and 0.72 vs. 0.82). AM3 and AM4 showed higher κ values than PM3 and PM4 in the internal validation dataset {0.266 [95% confidence interval (CI): 0.152-0.379] vs. 0.292 (95% CI: 0.178-0.405) and 0.254 (95% CI: 0.159-0.390) vs. 0.279 (95% CI: 0.163-0.396)} and test set [0.196 (95% CI: 0.029-0.362) vs. 0.268 (95% CI: 0.109-0.427) and 0.183 (95% CI: 0.015-0.351) vs. 0.228 (95% CI: 0.068-0.389)]. Conclusions: Using adversarial examples to train prostate cancer classification deep learning models can improve their generalizability and classification abilities.

3.
Quant Imaging Med Surg ; 12(2): 1163-1171, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35111613

ABSTRACT

BACKGROUND: This study aimed to exam the effects of thin-slab maximum intensity projection (TS-MIP) of computed tomography angiography (CTA) for collateral score (CS) and clot burden score (CBS) evaluation in patients with large-vessel-occlusion (LVO) stroke in the anterior circulation. METHODS: Of 241 consecutive patients with LVO stroke admitted to our center between August 2015 and June 2020, 187 patients were enrolled. CS and CBS were evaluated on conventional CTA and TS-MIP separately. Outcome at 90 days was classified as good if modified Rankin scale (mRS) was ≤2 and as poor if mRS was >2. The correlations between CS and CBS and clinical outcomes were assessed. Receiver operating characteristic (ROC) curve analysis was used to determine the diagnostic values of CS and CBS. Multivariate logistic regression analysis was performed to identify the independent predictors of 90-day good clinical outcomes. RESULTS: The correlation coefficient for clinical outcomes was significantly better for CS based on TS-MIP than that based on conventional CTA (-0.444 vs. -0.285, P=0.039); no significant difference was found in the CBS evaluation (TS-MIP: -0.356 vs. conventional CTA: -0.320, P=0.348). For predicting good clinical outcomes, TS-MIP-based CS was associated with larger area under the curve (AUC) (0.709 vs. 0.609, P=0.004) and higher sensitivity (69.1% vs. 42.0%, P=0.001) than CS based on CTA. In multivariable logistic regression analysis, the factors independently associated with good outcomes were National Institutes of Health Stroke Scale (NIHSS) score at admission (OR =1.147; P<0.001), TS-MIP-based CS (OR =0.326; P<0.001), final modified treatment in cerebral infarction (mTICI) score of 2b/3 (OR =0.098; P<0.001), and hemorrhagic transformation (OR =3.662; P<0.001). CONCLUSIONS: TS-MIP-CTA is superior to conventional CTA for evaluation CS and CBS, and TS-MIP-based CS may be a useful predictor of clinical outcome.

4.
Front Oncol ; 11: 697721, 2021.
Article in English | MEDLINE | ID: mdl-34568027

ABSTRACT

BACKGROUND: Apparent diffusion coefficients (ADCs) obtained with diffusion-weighted imaging (DWI) are highly valuable for the detection and staging of prostate cancer and for assessing the response to treatment. However, DWI suffers from significant anatomic distortions and susceptibility artifacts, resulting in reduced accuracy and reproducibility of the ADC calculations. The current methods for improving the DWI quality are heavily dependent on software, hardware, and additional scan time. Therefore, their clinical application is limited. An accelerated ADC generation method that maintains calculation accuracy and repeatability without heavy dependence on magnetic resonance imaging scanners is of great clinical value. OBJECTIVES: We aimed to establish and evaluate a supervised learning framework for synthesizing ADC images using generative adversarial networks. METHODS: This prospective study included 200 patients with suspected prostate cancer (training set: 150 patients; test set #1: 50 patients) and 10 healthy volunteers (test set #2) who underwent both full field-of-view (FOV) diffusion-weighted imaging (f-DWI) and zoomed-FOV DWI (z-DWI) with b-values of 50, 1,000, and 1,500 s/mm2. ADC values based on f-DWI and z-DWI (f-ADC and z-ADC) were calculated. Herein we propose an ADC synthesis method based on generative adversarial networks that uses f-DWI with a single b-value to generate synthesized ADC (s-ADC) values using z-ADC as a reference. The image quality of the s-ADC sets was evaluated using the peak signal-to-noise ratio (PSNR), root mean squared error (RMSE), structural similarity (SSIM), and feature similarity (FSIM). The distortions of each ADC set were evaluated using the T2-weighted image reference. The calculation reproducibility of the different ADC sets was compared using the intraclass correlation coefficient. The tumor detection and classification abilities of each ADC set were evaluated using a receiver operating characteristic curve analysis and a Spearman correlation coefficient. RESULTS: The s-ADCb1000 had a significantly lower RMSE score and higher PSNR, SSIM, and FSIM scores than the s-ADCb50 and s-ADCb1500 (all P < 0.001). Both z-ADC and s-ADCb1000 had less distortion and better quantitative ADC value reproducibility for all the evaluated tissues, and they demonstrated better tumor detection and classification performance than f-ADC. CONCLUSION: The deep learning algorithm might be a feasible method for generating ADC maps, as an alternative to z-ADC maps, without depending on hardware systems and additional scan time requirements.

5.
Eur Radiol ; 31(3): 1760-1769, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32935192

ABSTRACT

OBJECTIVES: We aimed to compare the efficiency of prostate cancer (PCa) detection using a radiomics signature based on advanced zoomed diffusion-weighted imaging and conventional full-field-of-view DWI. METHODS: A total of 136 patients, including 73 patients with PCa and 63 without PCa, underwent multi-parametric magnetic resonance imaging (mp-MRI). Radiomic features were extracted from prostate lesion areas segmented on full-field-of-view DWI with b-value = 1500 s/mm2 (f-DWIb1500), advanced zoomed DWI images with b-value = 1500 s/mm2 (z-DWIb1500), calculated zoomed DWI with b-value = 2000 s/mm2 (z-calDWIb2000), and apparent diffusion coefficient (ADC) maps derived from both sequences (f-ADC and z-ADC). Single-imaging modality radiomics signature, mp-MRI radiomics signature, and a mixed model based on mp-MRI and clinically independent risk factors were built to predict PCa probability. The diagnostic efficacy and the potential net benefits of each model were evaluated. RESULTS: Both z-DWIb1500 and z-calDWIb2000 had significantly better predictive performance than f-DWIb1500 (z-DWIb1500 vs. f-DWIb1500: p = 0.048; z-calDWIb2000 vs. f-DWIb1500: p = 0.014). z-ADC had a slightly higher area under the curve (AUC) value compared with f-ADC value but was not significantly different (p = 0.127). For predicting the presence of PCa, the AUCs of clinical independent risk factors model, mp-MRI model, and mixed model were 0.81, 0.93, and 0.94 in training sets, and 0.74, 0.92, and 0.93 in validation sets, respectively. CONCLUSION: Radiomics signatures based on the z-DWI technology had better diagnostic accuracy for PCa than that based on the f-DWI technology. The mixed model was better at diagnosing PCa and guiding clinical interventions for patients with suspected PCa compared with mp-MRI signatures and clinically independent risk factors. KEY POINTS: • Advanced zoomed DWI technology can improve the diagnostic accuracy of radiomics signatures for PCa. • Radiomics signatures based on z-calDWIb2000 have the best diagnostic performance among individual imaging modalities. • Compared with the independent clinical risk factors and the mp-MRI model, the mixed model has the best diagnostic efficiency.


Subject(s)
Multiparametric Magnetic Resonance Imaging , Prostatic Neoplasms , Diffusion Magnetic Resonance Imaging , Humans , Magnetic Resonance Imaging , Male , Prostatic Neoplasms/diagnostic imaging
6.
Quant Imaging Med Surg ; 9(6): 960-967, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31367550

ABSTRACT

BACKGROUND: Diabetes mellitus (DM) is associated with increased prevalence and severity of atherosclerosis. This study aimed to assess the prevalence and location of atherosclerosis in intracranial and extracranial vessels in diabetic patients and to investigate their association with ischemic stroke subtype. METHODS: Diabetes patients (n=128) and nondiabetic patients (n=195) were enrolled. Brain MRI, MR angiography, and digital subtraction angiography (DSA) imaging findings in the two groups were retrospectively compared. The characteristics of atherosclerosis (prevalence, location, severity) and collateral flow in diabetic and nondiabetic patients and their association with stroke subtype were analyzed. RESULTS: Atherosclerosis in extracranial vessels was more common in diabetes patients than in nondiabetic patients (43.8% vs. 23.1%; P<0.001). Symptomatic stenoses were commonly in the proximal internal carotid artery (ICA) and proximal vertebral artery (pVA). Diabetes patients were more likely to have lacunar infarction (49.2% vs. 32.3%; P=0.002) and less likely to have large artery infarct (36.7% vs. 48.2%; P=0.042). DM (OR, 2.03; 95% CI, 1.96-4.30; P=0.006) and age >65 years (OR, 2.55; 95% CI, 1.24-5.22; P=0.011) were independent risk factors for lacunar infarct. Diabetes patients with symptomatic extracranial stenosis or occlusion, combined with good collateral circulation, had significantly higher risk of lacunar infarction than nondiabetic patients (47.8% vs. 30.5%; P=0.045). CONCLUSIONS: DM aggravates the severity of extracranial atherosclerosis. Lacunar stroke is relatively common in diabetic patients and could even be due to large artery disease (LAD).

7.
J Endovasc Ther ; 26(1): 44-53, 2019 02.
Article in English | MEDLINE | ID: mdl-30580695

ABSTRACT

PURPOSE: To assess the diagnostic performance of quiescent-interval single-shot magnetic resonance angiography (QISS-MRA) at 3 tesla in diabetic patients with critical limb ischemia (CLI) vs contrast-enhanced MR angiography (CE-MRA) using digital subtraction angiography (DSA) as the standard of reference. METHOD: Thirty-seven consecutive diabetic patients (mean age 71.8±7.2 years; 30 men) with CLI (Fontaine stage III-IV) underwent QISS-MRA and CE-MRA with calf compression; DSA was the standard. Image quality (5-point Likert-type scale) and stenosis severity (5-point grading) for QISS-MRA and CE-MRA were evaluated by 2 blinded readers in 1147 and 654 vessel segments, respectively. Per-segment and per-region (pelvis, thigh, calf) sensitivity, specificity, positive predictive value, and negative predictive value were calculated. RESULTS: Image quality of QISS-MRA was lower compared with CE-MRA in the pelvic region (p<0.001 in both readers) and thigh region (p=0.033 in reader 1 and p=0.018 in reader 2), whereas in the calf region, the image quality of QISS-MRA was better than CE-MRA (p=0.009 in reader 1 and p=0.001 in reader 2). In segment-based analyses, there was no difference between QISS-MRA and CE-MRA in sensitivity [89.5% vs 90.3% in reader 1 (p=0.774) and 87.6% vs 90.6% in reader 2 (p=0.266)] or specificity [94.2% vs 92.9% in reader 1 (p=0.513) and 92.9% vs 92.9% in reader 2 (p>0.999)]. In region-based analyses, QISS-MRA and CE-MRA yielded similar sensitivity and specificity in all areas but the pelvic region for reader 2 (specificity 95.5% vs 84.8%, p=0.041). CONCLUSION: QISS-MRA performed very well in diabetic patients with CLI and was a good alternative for patients with contraindications to CE-MRA.


Subject(s)
Angiography, Digital Subtraction , Contrast Media/administration & dosage , Diabetic Angiopathies/diagnostic imaging , Gadolinium DTPA/administration & dosage , Ischemia/diagnostic imaging , Lower Extremity/blood supply , Magnetic Resonance Angiography , Peripheral Arterial Disease/diagnostic imaging , Aged , Critical Illness , Diabetic Angiopathies/physiopathology , Female , Humans , Ischemia/physiopathology , Male , Middle Aged , Observer Variation , Peripheral Arterial Disease/physiopathology , Predictive Value of Tests , Prospective Studies , Regional Blood Flow , Reproducibility of Results
8.
Cell Rep ; 24(12): 3207-3223, 2018 09 18.
Article in English | MEDLINE | ID: mdl-30232003

ABSTRACT

Increased aerobic glycolysis is a hallmark of cancer metabolism. How cancer cells coordinate glucose metabolism with extracellular glucose levels remains largely unknown. Here, we report that coactivator-associated arginine methyltransferase 1 (CARM1 or PRMT4) signals glucose availability to glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and suppresses glycolysis in liver cancer cells. CARM1 methylates GAPDH at arginine 234 (R234), inhibiting its catalytic activity. Glucose starvation leads to CARM1 upregulation, further inducing R234 hypermethylation and GAPDH inhibition. The re-expression of wild-type GAPDH, but not of its methylation-mimetic mutant, sustains glycolytic levels. CARM1 inhibition increases glycolytic flux and glycolysis. R234 methylation delays tumor cell proliferation in vitro and in vivo. Compared with normal tissues, R234 is hypomethylated in malignant clinical hepatocellular carcinoma samples. Notably, R234 methylation positively correlates with CARM1 expression in these liver cancer samples. Our findings thus reveal that CARM1-mediated GAPDH methylation is a key regulatory mechanism of glucose metabolism in liver cancer.


Subject(s)
Carcinoma, Hepatocellular/metabolism , Glucose/metabolism , Glyceraldehyde-3-Phosphate Dehydrogenases/metabolism , Glycolysis , Liver Neoplasms/metabolism , Protein-Arginine N-Methyltransferases/metabolism , Animals , Cells, Cultured , HEK293 Cells , Hep G2 Cells , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Protein-Arginine N-Methyltransferases/genetics
9.
Quant Imaging Med Surg ; 8(6): 568-578, 2018 Jul.
Article in English | MEDLINE | ID: mdl-30140619

ABSTRACT

BACKGROUND: To investigate the efficacy of retrograde recanalization for chronic total occlusion (CTO) of femoral-popliteal artery in patients with peripheral arterial disease. METHODS: In this single-center retrospective study, all patients who had undergone endovascular recanalization for femoral-popliteal CTOs at our center from June 2011 to October 2014 were included. Patients' demographics, immediate and follow-up outcomes were analyzed. RESULTS: A total of 205 patients with 238 CTOs were enrolled. In total, successful recanalization was achieved in 228 CTOs (95.8%). The antegrade procedure was successful in 196 CTOs. The retrograde procedure was successfully performed in 32 CTOs after failed antegrade procedure. Ankle-brachial index increased from 0.48±0.18 to 0.79±0.16 in antegrade group vs. 0.41±0.13 to 0.76±0.13 in retrograde group (P=0.438). Pulse score increased from 0.48±0.50 to 2.30±0.76 in antegrade group vs. 0.48±0.51 to 2.30±0.79 in retrograde group (P=0.771). At 12 and 24 months, primary patency rate was 86.2% (169/196) and 51.5% (101/196) in the antegrade group, and 75.0% (24/32) and 43.8% (14/32) in the retrograde group, respectively (P=0.346). Kaplan-Meier analysis showed limb salvage rates of 85.7% in the antegrade group vs. 78.1% in the retrograde group (P=0.198). CONCLUSIONS: Retrograde recanalization is effective for CTO of femoral-popliteal artery after the failure of an antegrade procedure; immediate outcomes and mid-term patency and limb salvage rate are comparable with that of antegrade procedure.

10.
Eur Radiol ; 28(6): 2708-2710, 2018 06.
Article in English | MEDLINE | ID: mdl-29318422

ABSTRACT

The original version of this article unfortunately contained mistakes. The legends to Figs. 2-4 were incorrectly interchanged. The correct versions are given below. The original article has been corrected.

11.
Eur Radiol ; 28(3): 897-909, 2018 Mar.
Article in English | MEDLINE | ID: mdl-28828514

ABSTRACT

OBJECTIVES: To investigate morphological characteristics used to predict recanalisation strategies in long-segment (>10 cm) femoral chronic total occlusion (LSF-CTO) angioplasty. METHODS: We retrospectively evaluated a range of morphological CTA and DSA features in patients who underwent recanalisation of LSF-CTO. The stage of CTO was classified into early (3-12 months) and late (>12 months) according to estimated duration. Characteristics including stump morphology, lesion length and calcification, proximal side branches, collaterals circulation, runoff vessels and concomitant arterial occlusion were used as predictors, and multivariate logistic regression analysis was performed to identify variables associated with late-stage CTO and retrograde technique. RESULTS: A total of 119 patients with 137 CTOs in 137 limbs were enrolled. Overall, successful recanalisation was achieved in 122 CTOs (89.1%). Flush occlusion [odds ratio (OR) 2.958; 95% confidence interval (CI) 1.172-7.465; p = 0.022], large collateral (OR 2.778; 95% CI 1.201-6.427; p = 0.017) and TransAtlantic Inter-Society Consensus II class D (TASC D) lesion (OR 1.743; 95% CI 1.019-2.981; p = 0.042) were predictors for late-stage CTO. Flush occlusion (OR 75.278; 95% CI 10.664-531.384; p < 0.001) and large collateral (OR 23.213; 95% CI 3.236-166.523; p = 0.002) were associated with high likelihood for retrograde approach. CONCLUSIONS: Flush occlusion and large collateral were associated with a CTO at late-stage which may require retrograde recanalisation. KEY POINTS: • CTO morphological characteristics help estimate lesion duration and optimise recanalisation strategies. • Flush occlusion and large collateral is associated with late-stage CTO and retrograde recanalisation. • Application of anterograde and retrograde recanalisation for long-segment femoral CTO is effective.


Subject(s)
Angioplasty/methods , Arterial Occlusive Diseases/diagnosis , Collateral Circulation/physiology , Femoral Artery/diagnostic imaging , Aged , Aged, 80 and over , Arterial Occlusive Diseases/physiopathology , Arterial Occlusive Diseases/surgery , Chronic Disease , Computed Tomography Angiography , Female , Femoral Artery/surgery , Humans , Male , Middle Aged , ROC Curve , Retrospective Studies , Treatment Outcome
12.
Therap Adv Gastroenterol ; 10(1): 11-19, 2017 Jan.
Article in English | MEDLINE | ID: mdl-28286555

ABSTRACT

BACKGROUND: We determined the feasibility of, and tissue response to silicone-covered biodegradable magnesium- and plastic-stent insertion into the esophagus in rabbits. METHODS: The mechanical compression-recovery characteristics and degradation behaviors of the magnesium stent were investigated in vitro. A total of 45 rabbits were randomly divided into a magnesium- (n = 15) and a plastic- (n = 15) stent group, and underwent stent insertion into the lower third of the esophagus under fluoroscopic guidance; a control group (n = 15) did not undergo the intervention. Esophagography was performed at 1, 2, and 4 weeks. Five rabbits in each group were euthanized at each time point for histological examination. RESULTS: Silicone-covered magnesium stents showed similar radial force to plastic stents (p > 0.05). The magnesium stents degraded rapidly in an acidic solution, but 90.2% ± 3.1% of the residual mass was maintained after a 2-week degradation in a solution with a pH of 4.0. All stent insertions were well tolerated. Magnesium stents migrated in six rabbits (one at 1 week, one at 2 weeks and four at 4 weeks), and plastic stents migrated in three rabbits (one at 2 weeks and two at 4 weeks; p > 0.05). Esophageal wall remodeling (thinner epithelial and smooth muscle layers) was similar in both stented groups (p > 0.05), and the esophagus wall was found to be significantly thinner in the stented groups than in the control group (p < 0.05). Esophageal injury and collagen deposition following stent insertion were similar and did not differ from the control group (p > 0.05). CONCLUSIONS: Esophageal silicone-covered magnesium stents provided reliable support for at least 2 weeks, with acceptable migration rates and without causing severe injury or tissue reaction compared with plastic stents.

13.
Eur Radiol ; 27(6): 2546-2553, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27704201

ABSTRACT

OBJECTIVES: Determine the feasibility of and tissue response to biodegradable magnesium-silicone stent insertion into the oesophagus of rabbits. METHODS: Mechanical compression-recovery and degradation behaviours of the stents were investigated in vitro. Thirty rabbits were randomly divided into a magnesium-silicone stent group (n = 15) that received stent insertion into the lower 1/3 of the oesophagus under fluoroscopic guidance and a control group (n = 15). Oesophagography was performed at 1, 2 and 4 weeks. Five rabbits in each group were euthanized at each time point for histological examination. RESULTS: Magnesium-silicone stents showed good flexibility and elasticity, and degraded more slowly than bare stents at pH 4.0 and 7.4. All stent insertions were well tolerated. The oesophageal diameters at 1, 2 and 4 weeks were 9.7 ± 0.7, 9.6 ± 0.8 and 9.6 ± 0.5 mm, respectively (vs. 9.2 ± 0.8 mm before intervention; P > 0.05). Stent migration occurred in six rabbits (one at 1 week, one at 2 and four at 4). Microscopy demonstrated dilation of the oesophageal wall within 1 week of insertion. Oesophageal injury and collagen deposition following stent insertion were similar to control (P > 0.05). CONCLUSIONS: Oesophageal magnesium-silicone stent insertion was feasible and provided reliable support for 2 weeks without causing oesophageal injury or collagen deposition. KEY POINTS: • Mg stent provided apparently adequate radial force and silicone membrane reduced magnesium biodegradation • Stent insertion provided good support for at least 2 weeks before biodegradation • Stenting effectively resulted in oesophageal wall remodelling, without demonstrable injury.


Subject(s)
Absorbable Implants , Esophagus/surgery , Magnesium/pharmacology , Silicone Elastomers/pharmacology , Stents , Animals , Feasibility Studies , Female , Foreign-Body Migration , Humans , In Vitro Techniques , Male , Prosthesis Design , Rabbits , Random Allocation
14.
Eur Radiol ; 27(7): 2835-2842, 2017 Jul.
Article in English | MEDLINE | ID: mdl-27796479

ABSTRACT

OBJECTIVES: To determine whether string-like lumina (SLs) on contrast-enhanced magnetic resonance angiography (CE-MRA) predict better outcomes in diabetic patients with below-the-knee (BTK) chronic total occlusions (CTOs). METHODS: This study involved 317 long-segment (>5 cm) BTK CTOs of 245 patients that were examined using CE-MRA and treated using endovascular angioplasty. An SL with a CTO was slowly filled with blood on conventional CE-MRA. Univariate and multivariate analyses were performed to identify predictors of procedural success, recanalisation method and immediate blood flow restoration. The target-lesion patency and limb-salvage rates were assessed. RESULTS: SL-positive CTOs (n = 60) achieved a higher technique success rate, preferred intraluminal angioplasty and better blood flow restoration than SL-negative CTOs (n = 257, P < 0.05). Multivariate analyses revealed that lesion length was the independent predictor of procedural success (P = 0.028). SL was a predictor of intraluminal angioplasty (P < 0.001) and good blood-flow restoration (P = 0.004). Kaplan-Meier analyses at 12 months revealed a higher target lesion patency rate (P = 0.04) and limb-salvage rate (P = 0.35) in SL-positive CTOs. CONCLUSIONS: In patients with BTK CTOs, SL predicted intraluminal angioplasty and good blood-flow restoration for BTK CTOs. KEY POINTS: • Intraluminal recanalisation was more frequently used for BTK-CTOs with SLs than without • CTO length was the only independent predictor of successful CTO recanalisation • SL was the only predictor of intraluminal angioplasty for BTK-CTOs • SL and CTO length were predictors of good blood-flow restoration after recanalisation • Restenosis-free and limb-salvage rates were better for SL-positive CTOs than SL-negative CTOs.


Subject(s)
Angioplasty/methods , Arterial Occlusive Diseases/diagnosis , Blood Flow Velocity/physiology , Contrast Media/pharmacology , Limb Salvage/methods , Magnetic Resonance Angiography/methods , Regional Blood Flow/physiology , Aged , Arterial Occlusive Diseases/physiopathology , Arterial Occlusive Diseases/surgery , Female , Follow-Up Studies , Humans , Knee , Male , Retrospective Studies , Time Factors , Treatment Outcome
15.
Korean J Radiol ; 17(6): 874-881, 2016.
Article in English | MEDLINE | ID: mdl-27833403

ABSTRACT

OBJECTIVE: To prospectively investigate predictors for good restoration of blood flow of below-the-knee (BTK) chronic total occlusions (CTOs) after endovascular therapy in diabetes mellitus (DM) patients. MATERIALS AND METHODS: A total of 120 long-segmental (≥ 5 cm) BTK, CTOs in 81 patients who underwent recanalization were included in this study. After angioplasty, blood-flow restoration was assessed using modified thrombolysis in myocardial ischemia grades and classified as good flow (grade 3) and poor flow (grade 1/2). One hundred and six CTOs with successful recanalization were divided into a good flow group (GFG; n = 68) and poor flow group (PFG; n = 38). Multivariate logistic regression analyses were undertaken to determine independent predictors of blood-flow restoration. Receiver operating characteristic curves were constructed to determine the best cutoff value. The prevalence of target-lesion restenosis during follow-up was compared between two groups. RESULTS: Univariate analyses suggested that CTOs in GFG were characterized by lighter limb ischemia (p = 0.03), shorter course of ischemic symptoms (p < 0.01) and lesion length (p = 0.04), more frequent use of intraluminal angioplasty (p = 0.03), and higher runoff score (p < 0.01) than those in PFG. Multivariate regression analyses suggested that distal runoffs (p = 0.001; odds ratio [OR], 10.32; 95% confidence interval [CI]: 4.082-26.071) and lesion length (p < 0.001; OR, 1.26; 95% CI: 1.091-1.449) were independent predictors for good flow restoration. Kaplan-Meier analyses at 12 months showed a higher prevalence of non-restenosis in GFG (p < 0.01). CONCLUSION: Distal runoffs and lesion length are independent predictors for good flow restoration for long-segmental BTK, CTOs in DM patients who receive endovascular therapy.


Subject(s)
Arterial Occlusive Diseases/therapy , Blood Flow Velocity/physiology , Diabetes Mellitus, Type 2/complications , Knee Joint/blood supply , Aged , Area Under Curve , Arterial Occlusive Diseases/complications , Arterial Occlusive Diseases/diagnostic imaging , Arterial Occlusive Diseases/physiopathology , Chronic Disease , Female , Femoral Artery/diagnostic imaging , Humans , Kaplan-Meier Estimate , Limb Salvage , Logistic Models , Magnetic Resonance Angiography , Male , Middle Aged , Odds Ratio , Predictive Value of Tests , ROC Curve , Regional Blood Flow/physiology , Retrospective Studies , Treatment Outcome
16.
Comput Methods Programs Biomed ; 125: 58-65, 2016 Mar.
Article in English | MEDLINE | ID: mdl-26701199

ABSTRACT

BACKGROUND: Diabetes mellitus is associated with an increased risk of liver cancer, and these two diseases are among the most common and important causes of morbidity and mortality in Taiwan. PURPOSE: To use data mining techniques to develop a model for predicting the development of liver cancer within 6 years of diagnosis with type II diabetes. METHODS: Data were obtained from the National Health Insurance Research Database (NHIRD) of Taiwan, which covers approximately 22 million people. In this study, we selected patients who were newly diagnosed with type II diabetes during the 2000-2003 periods, with no prior cancer diagnosis. We then used encrypted personal ID to perform data linkage with the cancer registry database to identify whether these patients were diagnosed with liver cancer. Finally, we identified 2060 cases and assigned them to a case group (patients diagnosed with liver cancer after diabetes) and a control group (patients with diabetes but no liver cancer). The risk factors were identified from the literature review and physicians' suggestion, then, chi-square test was conducted on each independent variable (or potential risk factor) for a comparison between patients with liver cancer and those without, those found to be significant were selected as the factors. We subsequently performed data training and testing to construct artificial neural network (ANN) and logistic regression (LR) prediction models. The dataset was randomly divided into 2 groups: a training group and a test group. The training group consisted of 1442 cases (70% of the entire dataset), and the prediction model was developed on the basis of the training group. The remaining 30% (618 cases) were assigned to the test group for model validation. RESULTS: The following 10 variables were used to develop the ANN and LR models: sex, age, alcoholic cirrhosis, nonalcoholic cirrhosis, alcoholic hepatitis, viral hepatitis, other types of chronic hepatitis, alcoholic fatty liver disease, other types of fatty liver disease, and hyperlipidemia. The performance of the ANN was superior to that of LR, according to the sensitivity (0.757), specificity (0.755), and the area under the receiver operating characteristic curve (0.873). After developing the optimal prediction model, we base on this model to construct a web-based application system for liver cancer prediction, which can provide support to physicians during consults with diabetes patients. CONCLUSION: In the original dataset (n=2060), 33% of diabetes patients were diagnosed with liver cancer (n=515). After using 70% of the original data to training the model and other 30% for testing, the sensitivity and specificity of our model were 0.757 and 0.755, respectively; this means that 75.7% of diabetes patients can be predicted correctly to receive a future liver cancer diagnosis, and 75.5% can be predicted correctly to not be diagnosed with liver cancer. These results reveal that this model can be used as effective predictors of liver cancer for diabetes patients, after discussion with physicians; they also agreed that model can assist physicians to advise potential liver cancer patients and also helpful to decrease the future cost incurred upon cancer treatment.


Subject(s)
Diabetes Mellitus, Type 2/complications , Internet , Liver Neoplasms/complications , Neural Networks, Computer , Humans , Liver Neoplasms/pathology , Risk Factors
17.
Vascular ; 24(2): 157-65, 2016 Apr.
Article in English | MEDLINE | ID: mdl-26002783

ABSTRACT

PURPOSE: To assess the technical feasibility and efficacy of the rendezvous technique, a type of subintimal retrograde wiring, for the treatment of long-segmental chronic total occlusions above the knee following unsuccessful standard angioplasty. METHODS: The rendezvous technique was attempted in eight limbs of eight patients with chronic total occlusions above the knee after standard angioplasty failed. The clinical symptoms and ankle-brachial index were compared before and after the procedure. At follow-up, pain relief, wound healing, limb salvage, and the presence of restenosis of the target vessels were evaluated. RESULTS: The rendezvous technique was performed successfully in seven patients (87.5%) and failed in one patient (12.5%). Foot pain improved in all seven patients who underwent successful treatment, with ankle-brachial indexes improving from 0.23 ± 0.13 before to 0.71 ± 0.09 after the procedure (P < 0.001). At the end of the follow-up period, the visual analogue scale improved from 6.86 ± 1.57 to 1.57 ± 1.27 (P < 0.001). Non-healing ulcers in three patients either healed (n = 2) or improved (n = 1). No major amputation was necessary. Kaplan-Meier analyses revealed that stenosis-free rate was 83.3% at six months and 41.7% at 12 months. CONCLUSION: The rendezvous technique is a feasible and effective treatment for chronic total occlusions above the knee when standard angioplasty fails.


Subject(s)
Angioplasty, Balloon/methods , Angioplasty/adverse effects , Femoral Artery , Lower Extremity/blood supply , Peripheral Arterial Disease/therapy , Popliteal Artery , Aged , Angioplasty, Balloon/adverse effects , Ankle Brachial Index , Chronic Disease , Constriction, Pathologic , Disease-Free Survival , Feasibility Studies , Female , Femoral Artery/diagnostic imaging , Femoral Artery/physiopathology , Humans , Kaplan-Meier Estimate , Limb Salvage , Male , Middle Aged , Peripheral Arterial Disease/diagnostic imaging , Peripheral Arterial Disease/physiopathology , Popliteal Artery/diagnostic imaging , Popliteal Artery/physiopathology , Recurrence , Retrospective Studies , Time Factors , Treatment Failure , Vascular Patency , Wound Healing
18.
PLoS One ; 10(10): e0140494, 2015.
Article in English | MEDLINE | ID: mdl-26484672

ABSTRACT

OBJECTIVES: To evaluate the efficacy of percutaneous aspiration thrombectomy (PAT) for infrainguinal arterial thromboembolism in patients undergoing endovascular recanalization (EVR) and to investigate the predictors for thromboembolic complications. MATERIALS AND METHODS: In total, 23 patients (23 limbs) who underwent PAT for thromboembolism (PAT group, PG) during EVR and 237 patients (302 limbs) who underwent successful EVR without thromboembolic complications (control group, CG) were enrolled. Immediate post-operation and follow-up outcomes were compared between the two groups. Multivariate analysis was performed to identify the predictors of thromboembolic complications. Technical success of PAT was defined as achievement of <30% residual stenosis and restoration of mTIMI grade 3. RESULTS: The technical success rate was 95.7% in PG. After intervention, the ankle-brachial index (ABI), restoration of blood flow and improvement in dorsal/plantar arterial pulse score showed no significant differences between PG and CG. During follow-up in PG, a sustained ABI improvement was observed in 63.6% (70.9% in CG), an improvement in walking distance in 68.8% (79.9% in CG,), ulcer healing in 75.0% (71.7% in CG) and restenosis/occlusion in 31.8% (25.2% in CG). The limb salvage rate was 100% in PG (96.0% in CG), and pain relief was observed in 66.7% patients with critical limb ischaemia (81.6% in CG). Superficial femoral artery involvement [0.233; 95% confidence interval (CI), 0.108-0.461; P < 0.001], de-novo lesion occlusion (683.8; 95% CI, 36.5-12804.6; P < 0.001) and intraluminal angioplasty (118.4; 95% CI, 8.0-1758.0; P = 0.001) was associated with high incidence of thromboembolism. CONCLUSION: PAT is a safe and effective treatment for thromboembolism during infrainguinal arterial EVR. SFA involvement, de-novo lesion occlusion and intraluminal angioplasty may be predictors of thromboembolic complications.


Subject(s)
Arterial Occlusive Diseases/surgery , Endovascular Procedures/methods , Thrombectomy/methods , Thromboembolism/surgery , Aged , Arterial Occlusive Diseases/etiology , Endovascular Procedures/adverse effects , Female , Humans , Logistic Models , Male , Middle Aged , Multivariate Analysis , Postoperative Complications/etiology , Postoperative Complications/surgery , Prognosis , Reproducibility of Results , Retrospective Studies , Risk Factors , Thromboembolism/etiology , Treatment Outcome
19.
J Plast Surg Hand Surg ; 49(6): 319-26, 2015.
Article in English | MEDLINE | ID: mdl-26083309

ABSTRACT

BACKGROUND: Flap necrosis is generally regarded as the result of vasospasm, thrombosis, and infection. METHODS: To improve skin flap survival and lower the risk of side effects due to systemic drug delivery, we formulated and evaluated compound gels for transdermal application. The transdermal delivery of 1% azithromycin (AZM), 0.5% amlodipine besylate (AB), and 300 IU/g low molecular weight heparin (LMWH) in compound gels, singly or in combinations, was measured across rat skin in vitro. The effects of AB and LMWH on flap blood circulation was investigated using fluorescein angiography, by transdermally applying the gel onto the surface of an in vivo ischaemic flap rat model; concentrations of the drugs were detected in both blood plasma and flap tissue at assigned timepoints. Finally, infected ischaemic flaps were treated to evaluate their anti-inflammatory effects and sizes of flap survival area. RESULTS: Each drug efficiently penetrated the in vitro skin in a time-dependent manner. In the in vivo ischaemic flaps, AB or LMWH increased the blood supply. All gel formulations that included AZM were associated with less flap inflammation. The surviving areas after treatment with AZM+LMWH or AZM+AB were significantly larger than that treated with the AZM-only gel, and the largest surviving area was that treated with AZM+AB+LMWH. Gels containing no AZM could not decrease flap inflammation or increase flap survival. CONCLUSION: Transdermal application of a compound gel with AZM, AB, and LMWH combined is a promising method to prevent and treat flap infection, improve blood circulation, and increase the survival of infected ischaemic flaps.


Subject(s)
Amlodipine/pharmacology , Azithromycin/pharmacology , Heparin, Low-Molecular-Weight/pharmacology , Surgical Flaps/blood supply , Surgical Wound Infection/drug therapy , Administration, Cutaneous , Animals , Chi-Square Distribution , Drug Therapy, Combination , Gels , Graft Survival , Humans , In Vitro Techniques , Ischemia/prevention & control , Rats , Risk Assessment , Surgical Flaps/microbiology , Surgical Wound Infection/diagnosis , Treatment Outcome
20.
J Endovasc Ther ; 22(2): 243-51, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25809370

ABSTRACT

PURPOSE: To compare the feasibility and efficacy of recanalizing below-the-knee (BTK) chronic total occlusions (CTOs) between patients with good or poor distal runoff based on magnetic resonance angiography (MRA) scans. METHODS: Two hundred long-segment BTK CTOs in 171 limbs of 113 diabetic patients (58 men; mean age 69.8±1.9 years) were divided into good distal runoff (GDR: 119 lesions, 98 limbs) or poor distal runoff groups (PDR: 81 lesions, 73 limbs) based on baseline MRA findings. After angioplasty, modified thrombolysis in myocardial ischemia (mTIMI) grades and ankle-brachial index (ABI) were used to assess immediate outcomes. Regularly scheduled duplex or MRA imaging was performed in follow-up. The restenosis and limb salvage rates were compared. RESULTS: The success rates were 93.3% and 87.7% in the GDR and PDR groups, respectively (p=0.21); subintimal angioplasty was more common in the PDR group (93.0% vs. 63.1%, p<0.01). Completion angiography indicated an mTIMI grade 3 blood flow in 71.2% lesions in the GDR patients and in 52.1% in the PDR (p=0.01) group. Improvement in the ABI was greater in the GDR limbs (p<0.001 vs. PDR). Mean imaging follow-up was 10.8±6.9 months in the GDR group and 11.1±6.6 months in the PDR group. Kaplan-Meier analysis showed a better restenosis-free rate in the GDR group (80.6% vs. 61.7%; p=0.02) at 12 months and for lesions with mTIMI grade 3 flow (p<0.01). At 24 months, Kaplan-Meier analysis revealed a better limb salvage rate in the GDR group (84.2% vs. 54.6%; p=0.02). CONCLUSION: Distal runoff detected using MRA could be a predictor for successful intraluminal recanalization, better distal tissue perfusion, improved long-term patency, and better limb salvage for patients with BTK CTOs.


Subject(s)
Angioplasty , Diabetic Angiopathies/diagnosis , Diabetic Angiopathies/therapy , Leg/blood supply , Magnetic Resonance Angiography , Peripheral Arterial Disease/diagnosis , Peripheral Arterial Disease/therapy , Aged , Angiography, Digital Subtraction , Angioplasty/adverse effects , Ankle Brachial Index , Blood Flow Velocity , Chronic Disease , Diabetic Angiopathies/physiopathology , Disease-Free Survival , Feasibility Studies , Female , Humans , Kaplan-Meier Estimate , Limb Salvage , Male , Middle Aged , Peripheral Arterial Disease/physiopathology , Predictive Value of Tests , Regional Blood Flow , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome , Ultrasonography, Doppler, Duplex , Vascular Patency
SELECTION OF CITATIONS
SEARCH DETAIL
...