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1.
《Diagnostic and interventional imaging》2020,101(9):555-564
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%. 相似文献
2.
《Journal of Clinical Orthopaedics and Trauma》2019,10(2):380-386
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices. 相似文献
3.
Outcome of conservative treatment of primary vesicoureteral reflux in 87 Thai children in a single center 总被引:1,自引:0,他引:1
PRAYONG VACHVANICHSANONG PORNSAK DISSANEEWATE APIRADEE LIM ALAN GEATER 《International journal of urology》2006,13(11):1393-1397
AIM: To evaluate the outcome of primary vesicoureteral reflux (VUR) using conservative treatment. METHODS: Eighty-seven children with primary VUR who had been treated with a conservative medical regimen and monitored through a yearly cystogram were recruited for the study. The study was conducted at the Pediatric Nephrology Clinic in Songklanagarind Hospital, the major tertiary care center in southern Thailand. Statistical analyses using Kaplan-Meier survival curves, chi-squared test, Fisher's exact test and multivariate analysis with Cox regression were performed. RESULTS: The study group consisted of 41 boys and 46 girls, with a total of 133 VUR. The age of the boys was significantly lower than that of the girls (P < 0.001). Resolution of the low grades (grades I-III) of VUR was significantly more frequent than that of the high grades (grades IV-V) (68/95, 72%vs 14/38, 37%; P < 0.001). Using the Kaplan-Meier survival analysis and log-rank test, the resolutions of VUR in boys versus girls, and age <1 years versus >or=1 years were not significantly different (P = 0.2252 and 0.4756, respectively). Low-grade VUR and unilateral VUR had significantly higher probabilities of resolution than high-grade VUR and bilateral VUR, respectively (P = 0.0041 and 0.0467, respectively). Multivariate Cox regression analysis indicated that among low-grade VUR, boys and unilateral VUR had significantly higher probabilities of resolution. Among the high-grade VUR, neither sex nor laterality had a significant effect on the probabilities of VUR resolution. CONCLUSION: This study offers more evidence that children with low-grade VUR have a higher chance of reflux resolution if they are boys and have only unilateral VUR. There is still no good guide for resolution of reflux in children with high-grade VUR. 相似文献
4.
5.
邢建枝 《华北煤炭医学院学报》2002,4(6):793-793
我院自 1997~ 2 0 0 1年以来 ,CT扫描诊断检查重症颅脑外伤 (GCS评分 3~ 8分 ) 16 4例 ,其中 16 1例平稳度过扫描期 ,3例因伤势严重在扫描过程中呼吸心跳停止 ,经抢救无效死亡。1 临床资料 16 4例重症颅脑损伤中 ,单纯颅内血肿 6 3例占 38% ;血肿伴脑挫裂伤 38例占 2 3% 相似文献
6.
目的 探讨儿童颈椎间盘钙化症的影像表现及诊断价值,并提高对本病的认识。方法 回顾分析16例儿童颈椎钙化性椎间盘病的影像表现。结果 16例患均行颈椎平片检查,5例行CT扫描并作了三维重建,8例行MRI检查。16例平片均显示了椎间盘钙化灶,均为单发,CT平扫加三维重建显示4例钙化呈卵圆形,1例钙化为不规则形。MRI检查不仅显示了椎间盘内改变还清晰显示了病变相邻椎体边缘信号改变,在T1、T2加权像上呈低信号。结论 平片检查可以显示椎间盘钙化;CT平扫加三维重建能清晰显示了钙化灶的大小、形态;MRI检查在显示受累椎体及周围组织的改变方面明显优于CT和平片。 相似文献
7.
8.
目的探讨小脑出血的原因、临床特点、CT表现、治疗及预后情况。方法回顾分析32例患者的临床及CT影像资料。结果本病多见于60岁以上,以高血压动脉硬化为主要原因,以突发性眩晕、呕吐为发病的主要症状,头颅CT检查可确诊。预后与患者年龄、出血量、出血部位、意识状态等多种因素密切相关。结论CT扫描可及时准确诊断,避免误诊漏诊,临床上根据患者的综合情况采取不同的救治策略有助于提高疗效,改善预后。 相似文献
9.
m. fox † r. sweis † t. wong † & a. anggiansah 《Neurogastroenterology and motility》2007,19(10):798-803
Oesophageal spasm presents with dysphagia and chest pain. Current treatments are limited by poor efficacy and side effects. Studies in health and oesophageal dysmotility show that sildenafil reduces peristaltic pressure and velocity; however the clinical efficacy and tolerability in symptomatic oesophageal spasm remains uncertain. We provided open-label sildenafil treatment to two patients with severe, treatment resistant symptoms associated with oesophageal spasm. The effects of sildenafil on oesophageal function and symptoms were documented by high resolution manometry (HRM). Patients were followed up to assess the efficacy of maintenance treatment with sildenafil b.i.d. HRM revealed focal and diffuse spasm in the smooth muscle oesophagus that were associated with symptoms in both cases, especially on swallowing solids. Lower oesophageal sphincter function was normal. A therapeutic trial of 25-50 mg sildenafil suppressed oesophageal contraction almost completely for water swallows; however effective, coordinated peristalsis returned with reduced frequency of spasm for solid swallows. Dysphagia and chest pain resolved during the therapeutic trial and efficacy was maintained on maintenance treatment with 25-50 mg sildenafil b.i.d. without troublesome side effects. This report shows that sildenafil can improve oesophageal function and relieve dysphagia and chest pain in patients with oesophageal spasm in whom other treatments have failed. 相似文献
10.
颈椎病与中医辨证关系的探讨(附100例分析) 总被引:3,自引:0,他引:3
目的:探讨颈椎病与中医分型的辨证关系。方法:对100例该病的影像表现与中医分型进行系统分析。结果:主要临床表现颈部活动受限,颈、肩、背部疼痛,常伴头痛、头晕、视物模糊、耳鸣等症状。风寒型以软组织所致颈曲改变为主。肝肾亏虚型、痰湿交阻型以骨质增生、椎间隙及椎间孔狭窄为主。结论:X线、CT是本病首选检查方法,能与中医辨证有机结合,对中西医治疗有重要意义。 相似文献