Differentiating autoimmune pancreatitis from pancreatic ductal adenocarcinoma with CT radiomics features

PurposeThe purpose of this study was to determine whether computed tomography (CT)-based machine learning of radiomics features could help distinguish autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma (PDAC).Materials and MethodsEighty-nine patients with AIP (65 men, 24 women; mean age, 59.7 ± 13.9 [SD] years; range: 21–83 years) and 93 patients with PDAC (68 men, 25 women; mean age, 60.1 ± 12.3 [SD] years; range: 36–86 years) were retrospectively included. All patients had dedicated dual-phase pancreatic protocol CT between 2004 and 2018. Thin-slice images (0.75/0.5 mm thickness/increment) were compared with thick-slices images (3 or 5 mm thickness/increment). Pancreatic regions involved by PDAC or AIP (areas of enlargement, altered enhancement, effacement of pancreatic duct) as well as uninvolved parenchyma were segmented as three-dimensional volumes. Four hundred and thirty-one radiomics features were extracted and a random forest was used to distinguish AIP from PDAC. CT data of 60 AIP and 60 PDAC patients were used for training and those of 29 AIP and 33 PDAC independent patients were used for testing.ResultsThe pancreas was diffusely involved in 37 (37/89; 41.6%) patients with AIP and not diffusely in 52 (52/89; 58.4%) patients. Using machine learning, 95.2% (59/62; 95% confidence interval [CI]: 89.8–100%), 83.9% (52:67; 95% CI: 74.7–93.0%) and 77.4% (48/62; 95% CI: 67.0–87.8%) of the 62 test patients were correctly classified as either having PDAC or AIP with thin-slice venous phase, thin-slice arterial phase, and thick-slice venous phase CT, respectively. Three of the 29 patients with AIP (3/29; 10.3%) were incorrectly classified as having PDAC but all 33 patients with PDAC (33/33; 100%) were correctly classified with thin-slice venous phase with 89.7% sensitivity (26/29; 95% CI: 78.6–100%) and 100% specificity (33/33; 95% CI: 93–100%) for the diagnosis of AIP, 95.2% accuracy (59/62; 95% CI: 89.8–100%) and area under the curve of 0.975 (95% CI: 0.936–1.0).ConclusionsRadiomic features help differentiate AIP from PDAC with an overall accuracy of 95.2%.     

Reduced nontarget embolization and increased targeted delivery with a reflux-control microcatheter in a swine model

PurposeTo evaluate the potential differences in non-target embolization and vessel microsphere filling of a reflux-control microcatheter (RCM) compared to a standard end-hole microcatheter (SEHM) in a swine model.Materials and methodsRadiopaque microspheres were injected with both RCM and SEHM (2.4-Fr and 2.7-Fr) in the kidneys of a preclinical swine model. Transarterial renal embolization procedures with RCM or SEHM were performed in both kidneys of 14 pigs. Renal arteries were selectively embolized with an automated injection protocol of radio-opaque microspheres. Ex-vivo X-ray microtomography images of the kidneys were utilized to evaluate the embolization by quantification of the deposition of injected microspheres in the target vs. the non-target area of injection. X-ray microtomography images were blindly analyzed by five interventional radiologists. The degree of vessel filling and the non-target embolization were quantified using a scale from 1 to 5 for each parameter. An analysis of variance was used to compare the paired scores.ResultsTotal volumes of radio-opaque microspheres injected were similar for RCM (11.5 ± 3.6 [SD] mL; range: 6–17 mL) and SEHM (10.6 ± 5.2 [SD] mL; range: 4–19 mL) (P = 0.38). The voxels enhanced ratio in the target (T) vs. non-target (NT) areas was greater with RCM (T = 98.3% vs. NT = 1.7%) than with SEHM (T = 89% vs. NT = 11%) but the difference was not significant (P = 0.30). The total score blindly given by the five interventional radiologists was significantly different between RCM (12.3 ± 2.1 [SD]; range: 6–15) and the standard catheter (11.3 ± 2.5 [SD]; range: 4–15) (P = 0.0073), with a significant decrease of non-target embolization for RCM (3.8 ± 1.3 [SD]; range: 3.5–4.2) compared to SEHM (3.2 ± 1.5 [SD]; range: 2.9–3.5) (P = 0.014).ConclusionIn an animal model, RCM microcatheters reduce the risk of non-target embolization from 11% to 1.7%, increasing the delivery of microspheres of 98% to the target vessels, compared to SEHM microcatheters.     

Prediction of steady-state bioequivalence relationships using single dose data I-linear kinetics

Simulated data using a linear one- and two-compartment body model with different absorption characteristics were used to evaluate the ability of single dose bioavailability data to predict the relationships that exist at steady state. This was done by comparing the confidence intervals obtained from single and multiple dose data sets for the parameters of Tmax, Cmax, and area under the curve from time zero to infinity (AUC0-infinity). As a consequence of Tmax and Cmax decreasing and increasing from single to multiple dosing regimens, the confidence intervals for these parameters reflected these changes. The 90 per cent confidence interval expressed as a percentage of the reference mean increased or decreased for Tmax dependent upon the ratio of Ka test/Ka reference, and decreased for Cmax while the interval for AUC0-infinity exhibited no predictable pattern and appeared to be influenced by the amount of error in the data set. Alteration of either the dosing interval or the fraction absorbed did not affect the pattern of change in the confidence intervals for Tmax and Cmax, but the latter did result in a decrease in the interval for AUC0-infinity. Analysis of the confidence intervals for Tmax, Cmax and AUC0-infinity in bioequivalency studies for quinidine gluconate and procainamide hydrochloride following administration of single and multiple doses to different subjects appeared to be consistent with the patterns observed for the simulated data sets.     

Treatment strategy for synchronous metastases of colorectal cancer: is hepatic resection after an observation interval appropriate?

Background In cases of synchronous colorectal hepatic metastases, the primary colorectal cancer strongly influences on the metastases. Our treatment policy has been to conduct hepatic resection for the metastases at an interval of 3 months after colorectal resection. We examined the appropriateness of interval hepatic resection for synchronous hepatic metastasis. Materials and methods The subjects were 164 patients who underwent resection of hepatic metastasis of colorectal cancer (synchronous, 70 patients; metachronous, 94 patients). Background factors for hepatic metastasis and postoperative results were compared for synchronous and metachronous cases. Results The cumulative survival rate for 164 patients at 3, 5, and 10 years postoperatively was 71.9%, 51.8%, and 36.6%, and the post-resection recurrence rate in remnant livers was 26.8%. Interval resection for synchronous hepatic metastases was conducted in 49 cases after a mean interval of 131 days. No difference was seen in postoperative outcome between synchronous and metachronous cases. Conclusion The outcome was similarly favorable in cases of synchronous hepatic metastasis and in cases of metachronous metastasis. Delaying resection allows accurate understanding of the number and location of hepatic metastases, and is beneficial in determining candidates for surgery and in selecting surgical procedure.     

A study of the interrupted REM episode

Brief interruptions of REM sleep are considered to be part of the REM episode. The maximum allowable duration of such an interruption, which is used to define the end of the REM episode, is currently a matter of debate. Making measurements on individual REM cycles, inter-REM interval analysis was carried out to determine whether the generally adopted 15 minute empirical rule for this maximum needs to be extended to 25 minutes as suggested by several including Kobayashi et al. Our results show that there is no reason to alter the 15 minute rule and that measurements which do not take into account the time-of-night effect may be misleading. The proportion of interrupted REM episodes observed in our population of healthy adults is high. We have therefore also examined in some detail the phenomenology of the temporal evolution of the structure and content of the interrupted REM episodes. Both showed a definite change over the night: the interruptions in the earlier episodes tend to return the system to slow wave sleep while those in the later episodes tend to return it to wake. It is hypothesized that these interruptions reflect a measure of REM sleep pressure and its interaction with both slow wave sleep and wake pressures.     

中性粒细胞分布数据序列小波变换研究

目的　研究小波分析结合复倒谱处理血膜中中性粒细胞分布数据信号的新方法及临床意义。方法　利用“虚拟盒计数法”方法采集血膜中的细胞分布数据信号 ,然后进行小波变换结合复倒谱分析方法处理。结果　提出血膜中细胞分布状态的“密集子”新概念。计算出小波变换复倒谱主极大值 ,并以此作为不同情况下血膜中中性粒细胞分布“密集子”间距的准确参数。结论　方法简单 ,能较好的反映血膜中细胞分布状态的微观组织结构特征 ,是血膜中细胞“密集子”表达定征的一种有效方法     

Osteotomy around the knee: Assessment of quality,content and readability of online information

BackgroundAs knee osteotomy surgery becomes increasingly accessible, more patients may turn to the Internet for information. This study examined the source, quality, content and readability of online information regarding osteotomy around the knee.MethodsThe first 70 websites returned by the top four search engines were identified using the key words: “knee osteotomy” and “high tibial osteotomy.” The websites were categorised by type and assessed using the DISCERN score, Journal of the American Medical Association (JAMA) benchmark criteria and a novel Knee Osteotomy-Specific Score (KOSS). The presence of the Health On the Net (HON) code accreditation seal was noted. Readability of each website was assessed using eight readability formulae. The mean reading grade level (RGL) was compared to the 6th and 8th grade reading levels. The mean RGL of each category was also compared.ResultsOf the 45 unique websites analysed, the majority were Physician (33%) and Journal websites (31%). The mean DISCERN score was 36.7 (±8.9) which is classified as ‘poor.’ The mean JAMA benchmark criteria score was 2.04 (±1.5) and Physician websites were most likely to be scored zero. The mean KOSS was 15.4 (±5.7). The highest scoring website was a Commercial site but, overall, Journal category sites provided the best quality information. Websites that bore the HONcode seal obtained higher DISCERN, JAMA benchmark criteria and Knee Osteotomy - Specific Scores.The cumulative mean RGL was 13.2 (±2.2) which exceeded the 6th grade level by an average of 7.2 grade levels and the 8th grade level by an average of 5.2 grade levels. No website (0%) was written at or below either the 6th or the 8th grade reading levels. The mean Flesch Reading Ease Score of all websites was 41.13 (±14.7) which is classified as ‘difficult.’ Journal websites had the highest RGL.ConclusionThe information available online regarding osteotomy around the knee varies tremendously in quality and completeness. Physician sites predominate, but these were among the lowest scoring of all websites. Even where high quality information is available, it is set at too high a level to be easily understood.Level of evidenceSurvey of materials – Internet.     

交互信息在心脏状态和心率研究中的应用

交互信息是一种检测系统之间相依性的方法 ,它可以同时检测线性和非线性相关。本文介绍了交互信息的计算方法和性质 ,讨论了它在单个时间序列上的应用 ,并将它应用于心脏状态研究上。利用实验动物的数据 ,我们发现了心搏的运动既不是随机的也不是周期的 ;并且 ,不同心脏状态下的交互信息有很大的差别 ,浅麻 ,机控呼吸和开胸状态下交互信息都相对较小 ,心肌损伤后有明显增大 ,提示心搏的交互信息与心脏健康程度有很大关系     

Risk of appendiceal neoplasm after interval appendectomy for complicated appendicitis: A systematic review and meta-analysis

BackgroundNon-operative management is often the treatment of choice in cases of complicated appendicitis and routine interval appendectomy is not usually recommended. Actually, recent studies show an alarming number of appendiceal neoplasms following interval appendectomy. The aim of this study is to evaluate the prevalence of appendiceal neoplasms and their histological types after interval appendectomy for complicated appendicitis in adults.MethodsA comprehensive literature search of the PubMed, Scopus and Web of Science databases was conducted according to the PRISMA statement. Studies reporting appendiceal neoplasm rates after interval appendectomy and histopathological characteristics were included. The most recent World Health Organization (WHO) classification of malignant tumours was considered. A pooled prevalence analysis for both prevalence and pathology was performed.ResultsA total of eight studies was included: seven retrospective series and one randomized controlled trial. The pooled prevalence of neoplasms after interval appendectomy was 11% (95% CI 7–15; I² = 37.5%, p = 0.13). Appendiceal mucinous neoplasms occurred in 43% (95% CI 19–68), adenocarcinoma in 29% (95% CI 6–51), appendiceal neuroendocrine neoplasm in 21% (95% CI 6–36), globet cell carcinoma in 13% (95% CI -2-28), adenoma or serrated lesions in 20% (95% CI -0-41) of cases.ConclusionThe risk of appendiceal neoplasm in patients treated with interval appendectomy for complicated appendicitis is 11%; mucinous neoplasm is the most common histopathological type. Further studies should investigate this association in order to clarify the biological pathway and clinical implications.