Magnetic susceptibility is an intrinsic physical quantity which describes the relationship between material magnetization and applied external magnetic field. Quantitative susceptibility mapping (QSM) is an MRI technology which can quantify the buck magnetic susceptibility of tissue in vivo. It is particularly effective at elucidating anatomy with paramagnetic or diamagnetic components. QSM technology is a method for solving the ill-pose problem of un-conventional de-convolution of the measured tissue magnetic field with the unit magnetic dipole field to obtain the susceptibility source map. Many multi orientation scan based QSM and clinically acceptable single orientation QSM methods have been proposed to solve this ill-posed problem. In this paper, the QSM concept is introduced and the various QSM methods are systematically categorized and discussed. The aim of this paper is to summarize the current research progress of QSM, popularize the knowledge of QSM and promote the improvements and the rational application of QSM in clinical field.
ObjectiveTo evaluate the effect of the timing of surgery on treating refractory epilepsy caused by cavernomas. Method63 patients with refractory epilepsy caused by intracranial supratentorial cavernomas were retrospectively analyzed on the duration of epilepsy, epileptogenesis sitations, and epileptic seizure types. After resection surgeries of cavernomas, the surgical outcomes were compared between the patients with shorter duration of seizures and the longer ones. ResultThe durations of epilepsy were beteen 3 months and 25 years, median 4.5 years. The temporal epilepsies were 43, frontal 12, parietal 3, occipital 1, cingulate gyrus 1, and multiple lobe 3. The overall ILAE class 1 outcome was 71.4% in 63 patients at 2-year-followup, and ILAE class 1 and 2 outcome was 81.6%. The seizure free rate in the group with epilepsy duration shorter than 5 years was 92.1%, better than the 56.0% in the group with epilepsy duration longer than 5 years. ConclusionOnce the diagnosis of medical refractory epilepsy caused by cavernoma was confirmed, the early surgical operation should be considered seriously.
ObjectiveTo investigate the role of laparoscopic pancreaticoduodenectomy (LPD) for periampullary carcinoma. MethodsThis is a retrospective review of all periampullary carcinomas consecutively performed between January 2013 and January 2016 in Zhejiang Provincial People's Hospital. ResultsFifty-one patients underwent LPD. Conversion to open procedure was required in three cases. The operative time was (370±104) min, The estimated blood loss was (220.7±180.9) mL. Five cases had binding pancreaticogastric anastomosis, the other patients underwent duct to mucosa pancreaticojejunal anastomosis. Post operatively hospital stay was (14.6±11.2) days. The represented morbidity including pancreatic fistula (9 cases), postoperative intraperitoneal bleeding (2 cases), postoperative gastrointestinal bleeding (2 cases), delayed gastric emptying (4 cases), and bile leakage (4 cases). All patients underwent R0 resection. Postoperative pathological results: pancreatic adenocarcinoma: 28 cases, duodenal papillary adenocarcinoma: 12 cases, common bile duct adenocarcinoma: 11 cases. Conciusions LPD has been proven to be a safe procedure. Our LPD approach can improve the effectiveness of lymphadenectomy. It combined with resection of portal vein can improve the R0 resection rate of periampullary adenocarcinoma and is associated with better survival of those patients.