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Abstract Background Deep-learning-based computer-aided diagnosis (DL-CAD) systems using MRI for prostate cancer (PCa) detection have demonstrated good performance. Nevertheless, DL-CAD systems are vulnerable to high heterogeneities in DWI, which can interfere with DL-CAD assessments and impair performance. This study aims to compare PCa detection of DL-CAD between zoomed-field-of-view echo-planar DWI (z-DWI) and full-field-of-view DWI (f-DWI) and find the risk factors affecting DL-CAD diagnostic efficiency. Methods This retrospective study enrolled 354 consecutive participants who underwent MRI including T2WI, f-DWI, and z-DWI because of clinically suspected PCa. A DL-CAD was used to compare the performance of f-DWI and z-DWI both on a patient level and lesion level. We used the area under the curve (AUC) of receiver operating characteristics analysis and alternative free-response receiver operating characteristics analysis to compare the performances of DL-CAD using f- DWI and z-DWI. The risk factors affecting the DL-CAD were analyzed using logistic regression analyses. P values less than 0.05 were considered statistically significant. Results DL-CAD with z-DWI had a significantly better overall accuracy than that with f-DWI both on patient level and lesion level (AUCpatient: 0.89 vs. 0.86; AUClesion: 0.86 vs. 0.76; P

Objective: The purpose of this study was to identify the difference between dual energy spectral computed tomography (DECT) and magnetic resonance imaging (MRI) used to detect liver/cardiac iron content in Myelodysplastic syndrome (MDS) patients with differently adjusted serum ferritin (ASF) levels.Method: Liver and cardiac iron content were detected by DECT and MRI. Patients were divided into different subgroups according to the level of ASF. The receiver operating characteristic curve (ROC) analysis was applied in each subgroup. The correlation between iron content detected by DECT/MRI and ASF was analyzed in each subgroup.Result: ROC curves showed that liver virtual iron content (LVIC) Az was significantly less than liver iron concentration (LIC) Az in the subgroup with ASF < 1,000 ng/ml. There was no significant difference between LVIC Az and LIC Az in the subgroup with 1,000 ≤ ASF < 2,500 ng/ml and 2,500 ≤ ASF < 5,000 ng/ml. LVIC Az was significantly higher than LIC Az in the subgroup with ASF 5,000 mg/L in LIC, LIC became correlated with ASF. There was no significant difference between the subgroup with 2,500 ≤ ASF < 5,000 ng/ml and 5,000 ng/ml ≤ ASF in LIC expression. Furthermore, both LIC and liver VIC had significant correlations with ASF in patients with ASF < 2,500 ng/ml, while LVIC was still correlated with ASF, LIC was not correlated with ASF in patients with 2,500 ng/ml ≤ ASF. Moreover, neither cardiac VIC nor myocardial iron content (MIC) were correlated with ASF in these subgroups.Conclusion: MRI and DECT were complementary to each other in liver iron detection. In MDS patients with high iron content, such as ASF ≥ 5,000 ng/ml, DECT was more reliable than the MRI in the assessment of iron content. But in patients with low iron content, such as ASF < 1,000 ng/ml, MRI is more reliable than DECT. Therefore, for the sake of more accurately evaluating the iron content, the appropriate detection method can be selected according to ASF.

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.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

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. [ABSTRACT FROM AUTHOR]

The detection rate of prostate cancer (PCa) using traditional biopsy guided by transrectal ultrasound (TRUS) is not satisfactory. The aim of this study was to determine the utility of 3-Tesla (3-T) magnetic resonance imaging (MRI) prior to TRUS-guided prostate biopsy and to investigate which subgroup of patients had the most evident improvement in PCa detection rate. A total of 420 patients underwent 3-T MRI examination prior to the first prostate biopsy and the positions of suspicious areas were recorded respectively. TRUS-guided biopsy regimes included systematic 12-core biopsy and targeted biopsy identified by MRI. Patients were divided into subgroups according to their serum prostate-specific antigen (PSA) levels, PSA density (PSAD), prostate volume, TRUS findings and digital rectal examination (DRE) findings. The ability of MRI to improve the cancer detection rate was evaluated. The biopsy positive rate of PCa was 41.2% (173/420), and 41 of the 173 (23.7%) patients were detected only by targeted biopsy in the MRI-suspicious area. Compared with the systematic biopsy, the positive rate was significantly improved by the additional targeted biopsy (P=0.0033). The highest improvement of detection rate was observed in patients with a PSA level of 4-10 ng/ml, PSAD of 0.12-0.20 ng/ml², prostate volume >50 ml, negative TRUS findings and negative DRE findings (P<0.05). Therefore, it is considered that 3-T MRI examination could improve the PCa detection rate on first biopsy, particularly in patients with a PSA level of 4-10 ng/ml, PSAD of 0.12-0.20 ng/ml², prostate volume of >50 ml, negative TRUS findings and negative DRE findings. [ABSTRACT FROM AUTHOR]

Rationale and Objectives: To compare the clinical outcomes of retrograde transplantar arch angioplasty and conventional below-the-knee (BTK) anterograde recanalization. Materials and Methods: One hundred twelve limbs in 96 patients underwent attempt at antegrade tibial angioplasty. Among 27 technical failures, retrograde trans-dorsal or -planter percutaneous transluminal angioplasty was attempted in 22 limbs. Ankle-brachlal index (ABI), thrombolysis In myocardial infarction (TIMI) flow grade, and dorsal/plantar arterial pulse score improvement were compared immediately after the procedures between patients received successful anterograde angioplasty (anterograde angioplasty group [AAG], 85 limbs in 71 patients) and retrograde angioplasty (retrograde angioplasty group [RAG], 22 limbs in 20 patients). Target vessel restenosis and limb salvage were observed during follow-up. Results: Primary technical success rate was 75.9% in the RAG (vs. 74.0% AAG, P > .05). ABI Improved from 0.55 ± 0.21 to 0.93 ± 0.19 in the RAG (vs. 0.56 ± 0.14 to 0.89 ± 0.18 AAG, P > .05). TIMI flow grade demonstrated greater reperfusion of distal foot tissue in the RAG (2.3 ± 0.8 vs. 1.0 ± 0.8, P< .05). Primary patency rates at 12 and 24 months were 63.6% (14 of 22) and 45.5% (10 of 22) in the RAG and 52.9% (45 of 85) and 37.6% (32 of 85) In the AAG, respectively (P > .05). Kaplan-Meier analysis after 24 months found limb salvage rates of 93.8% in the RAG and 96.5% in the AAG (P > .05). Conclusions: Retrograde transplantar arch angioplasty achieved better immediate blood flow and similar ABI improvement, primary patency rate, and limb salvage rate compared to conventional transtibial angioplasty for BTK occlusions. This could become a supplemen-tary technique when anterograde angioplasty fails. [ABSTRACT FROM AUTHOR]

Background and Aim: To retrospectively analyze and compare the clinical efficacy of temporary stent insertion with pneumatic dilation of the same diameter in the treatment of achalasia based on a long-term follow up. Methods: A total of 101 treated achalasia patients were divided into a pneumatic dilation group (Group A, n = 38) and a temporary stent insertion group (Group B, n = 63). The diameter of the balloon or stent used was 30 mm. The total symptom scores (TSS) and esophageal manometry were used to assess the symptoms and lower esophageal sphincter (LES) pressure improvement. Barium swallow–esophageal studies were used to assess esophageal emptying objectively. TSS and LES pressure improvement were assessed, recorded, and compared during the regular interval follow up. Results: Forty-nine pneumatic dilations and 65 stent insertions were successfully performed in all patients under fluoroscopy. Complications included pain, reflux, and bleeding, which occurred in nine (23.6%), eight (21.1%), and three (8%) patients in Group A, and in 27 (42.9%), eight (12.7%), and 10 (15.9%) patients in Group B, respectively. The stent was retained approximately 4–7 days and was retrieved via endoscope. TSS, esophageal manometry, and barium esophagram post-treatment significantly improved compared to those given pretreatment ( P < 0.0001). At the end of follow up, TSS and LES pressure in Group B were 4.00 ± 1.00 and 43.67 ± 12.66 mmHg, compared to 10.20 ± 0.45 ( P = 0.0096) and 58.60 ± 8.65 mmHg ( P = 0.1687) in Group A. The Kaplan–Meier method revealed better symptom remission in Group B compared to Group A (log–rank test, P = 0.0212). Conclusion: Retrievable stent placement is more effective than the same diameter pneumatic dilation for the treatment of achalasia with a long-term follow up. [ABSTRACT FROM AUTHOR]

The aim of this retrospective study was to evaluate the clinical efficacy and limitations of different endovascular modalities in the treatment of very large and giant intracranial aneurysms. A group of 20 patients with very large and giant intracranial aneurysms treated by endovascular approaches were retrospectively analyzed. Of the 20 patients, 9 had been treated by parent artery occlusion, 8 by coil embolization, and 3 with an intracranial covered stent. Two recurrent aneurysms initially treated with coil embolization were retreated with an intracranial covered stent. Patients were followed for 9–83 months after the procedure. Endovascular treatment was technically feasible in all 20 patients. One patient died 7 days after the procedure from rebleeding caused by incomplete aneurysmal occlusion. Immediate postprocedural angiograms showed that complete occlusion was achieved in 11 aneurysms, subtotal occlusion in 7, and incomplete occlusion in 2. The final angiographic results in the other 19 surviving patients confirmed complete occlusion of 15 aneurysms, subtotal occlusion in 3, and incomplete occlusion in 1. Clinical evaluations performed at the final follow-up visit showed an excellent outcome in 11 patients and a good outcome in 8. Endovascular treatment of giant intracranial aneurysms with coil embolization is often associated with a low complete occlusion rate and a high recanalization rate, and parent artery occlusion remains a practical option in selected patients. Based on our limited experience, the use of an intracranial covered stent appears to be a relatively simple and safe procedure for occluding very large and giant aneurysms while still maintaining the patency of the parent artery. [ABSTRACT FROM AUTHOR]

BackgroundApparent 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.ObjectivesWe aimed to establish and evaluate a supervised learning framework for synthesizing ADC images using generative adversarial networks.MethodsThis 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.ResultsThe 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.ConclusionThe 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.