Hemispheric Activation of Anterior and Inferior Prefrontal Cortex during Verbal Encoding and Recognition: A PET Study of Healthy Volunteers

Evidence of bilateral prefrontal activation during memory encoding and retrieval has increased attention given to anatomical subdivisions within the prefrontal cortex. The current study examined anterior and inferior aspects of the prefrontal cortex to determine their degree of functional and hemispheric overlap during encoding and recognition. Cerebral blood flow of 25 healthy volunteers was measured using PET ¹⁵O-water methods during four conditions: resting baseline, sequential finger movement, word encoding, and word recognition. Resting and motor images were averaged to provide a single reference that was subtracted from encoding and recognition using statistical parametric mapping (SPM96). Memory conditions were also subtracted from each other to identify differences in regional activity. Subjects performed well (86% correct) and had a slightly conservative response bias. Baseline subtraction from encoding revealed focal activation of left inferior prefrontal cortex (area 45) without significant contralateral activation. Recognition minus baseline subtraction produced a focal right anterior prefrontal activation (areas 9 and 10) that was not present in the left hemisphere. Bilateral effects were seen in area 45 during recognition. Subtraction of memory tasks from each other did not reveal any areas of greater activity during encoding. However, the recognition task produced greater activation in right area 9 extending into the anterior cingulate. Greater activity during recognition was also observed in left insula and bilateral visual integration areas. These results are discussed in relation to the prevailing model of prefrontal hemispheric asymmetry during episodic memory.     

Localization of Language-Related Cortex withO-Labeled Water PET in Patients with Gliomas

Measurement of relative cerebral blood flow (CBF) with¹⁵O-labeled water PET has been widely used for brain mapping experiments on language functions in normal volunteers and patients with epilepsy. We focused on the question of whether PET during speech activation is an appropriate method for noninvasive determination of language-related cortex in patients with brain tumors. Furthermore, the suitability of the method for determination of hemispheric language dominance was examined and compared to the results of the Edinburgh Handedness Inventory. Ten right-handed and six left-handed patients with gliomas were examined prior to surgery while repeatedly performing word repetition and verb generation tasks. A set of volumes of interest (VOIs) was drawn on coregistered MRI in order to account for anatomic variability as well as anatomical alterations due to tumor mass effect. Repetition of nouns did not produce significant hemispheric differences. During stimulation by verb generation, reliable lateralized activations of Broca's area and supplementary motor area were detected in all right-handed patients. Of the left-handed patients, two showed clear right lateralization, two activated Broca's area bilaterally, and two had a pattern similar to that of right-handers. Patients with bilateral activations showed the strongest tendency toward bihandedness according to the handedness inventory. Lateralization of supplementary motor area in left-handers corresponded to lateralized activity in Broca's area. Tumors in the vicinity of language-related regions did not alter activation responses. In conclusion, measurement of CBF changes during verb generation permits identification of language-related areas in patients with gliomas with strong lateralization related to hemispheric dominance. These findings may be of particular clinical interest for left-handed patients.     

PET用于检出亨廷顿病进展

亨廷顿病(HD)由中枢神经系统退行性变引起,明显损害患者认知、情绪及运动等,尤其是运动功能,可导致典型舞蹈样动作.目前影像学诊断HD仍存在一定困难.PET脑代谢显像、多巴胺系统显像、脑内受体显像及相关多模态显像技术等可提高HD检出率.本文对PET检测HD的应用进展进行综述.     

Uptake and retention of manganese contrast agents for PET and MRI in the rodent brain

Manganese‐enhanced magnetic resonance imaging (MRI) is an established neuroimaging method for signal enhancement, tract tracing, and functional studies in rodents. Along with the increasing availability of combined positron emission tomography (PET) and MRI scanners, the recent development of the positron‐emitting isotope ⁵²Mn has prompted interest in the use of Mn²⁺ as a dual‐modality contrast agent. In this work, we characterized and compared the uptake of systemically delivered Mn²⁺ and radioactive ⁵²Mn²⁺ in the rat brain for MRI and PET, respectively. Additionally, we examined the biodistribution of two formulations of ⁵²Mn²⁺ in the rat. In MRI, maximum uptake was observed one day following delivery of the highest MnCl₂ dose tested (60 mg/kg), with some brain regions showing delayed maximum enhancement 2–4 days following delivery. In PET, we observed low brain uptake after systemic delivery, with a maximum of approximately 0.2% ID/g. We also studied the effect of final formulation vehicle (saline compared with MnCl₂) on ⁵²Mn²⁺ organ biodistribution and brain uptake. We observed that the addition of bulk Mn²⁺ carrier to ⁵²Mn²⁺ in solution resulted in significantly reduced ⁵²Mn²⁺ uptake in the majority of organs, including the brain. These results lay the groundwork for further development of ⁵²Mn PET or dual Mn‐enhanced PET–MR neuroimaging in rodents, and indicate several interesting potential applications of ⁵²Mn PET in other organs and systems. Copyright © 2016 John Wiley & Sons, Ltd.     

PET/MRI在癫痫中的应用进展

癫痫是一种常见的神经系统疾病,因其病情易反复发作,给患者及其家庭带来了极大的负担。近年来,神经影像学领域经历着快速的发展,将MRI的高组织对比度和高空间分辨率与正电子发射断层扫描(positron emission computed tomography,PET)的代谢敏感性相结合的PET/MRI应运而生,PET/MRI在对癫痫患者的致痫灶定位以及改善手术结局中表现出明显优势。笔者对PET/MRI在癫痫中的应用进展进行阐述。     

PET in cardiology: current status and clinical expectations

Summary. The development of positron emission tomography (PET) in the clinical environment along with the synthesis of biologically active molecules and tracer kinetic principles has provided a diagnostic tool for in vivo tissue characterization in humans. Moreover, based on the growing knowledge of cellular function on the molecular level of diseases PET biological imaging has stimulated the synthesis of numerous metabolic compounds labelled with the four primary positron-emitting radioisotopes C-ll, F-18, N-13 and 0–15. While the concept of biological imaging has gained attraction for probing both the central nervous system and neoplastic tissues, current diagnostic benefit from PET is probably best defined in cardiovascular medicine.     

Common carotid segmentation in 18F-sodium fluoride PET/CT scans: Head-to-head comparison of artificial intelligence-based and manual method

Background

Carotid atherosclerosis is a major cause of stroke, traditionally diagnosed late. Positron emission tomography/computed tomography (PET/CT) with ¹⁸F-sodium fluoride (NaF) detects arterial wall micro-calcification long before macro-calcification becomes detectable by ultrasound, CT or magnetic resonance imaging. However, manual PET/CT processing is time-consuming and requires experience. We compared a convolutional neural network (CNN) approach with manual segmentation of the common carotids.

Methods

Segmentation in NaF-PET/CT scans of 29 healthy volunteers and 20 angina pectoris patients were compared for segmented volume (Vol) and mean, maximal, and total standardized uptake values (SUVmean, SUVmax, and SUVtotal). SUVmean was the average of SUVmeans within the VOI, SUVmax the highest SUV in all voxels in the VOI, and SUVtotal the SUVmean multiplied by the Vol of the VOI. Intra and Interobserver variability with manual segmentation was examined in 25 randomly selected scans.

Results

Bias for Vol, SUVmean, SUVmax, and SUVtotal were 1.33 ± 2.06, −0.01 ± 0.05, 0.09 ± 0.48, and 1.18 ± 1.99 in the left and 1.89 ± 1.5, −0.07 ± 0.12, 0.05 ± 0.47, and 1.61 ± 1.47, respectively, in the right common carotid artery. Manual segmentation lasted typically 20 min versus 1 min with the CNN-based approach. Mean Vol deviation at repeat manual segmentation was 14% and 27% in left and right common carotids.

Conclusions

CNN-based segmentation was much faster and provided SUVmean values virtually identical to manually obtained ones, suggesting CNN-based analysis as a promising substitute of slow and cumbersome manual processing.     

SPECT vs. PET monitoring of bone defect healing and biomaterial performance in vivo

Quantification of the bone healing processes by X‐ray‐based methods becomes inaccurate in the presence of radiopaque synthetic materials. In this study, single photon emission computed tomography (SPECT) and positron emission tomography (PET) were compared as alternatives to follow in vivo bone healing in a rat calvarial defect model. SPECT/computed tomography (CT) following administration of ^99mtechnetium‐labelled hydroxymethylene diphosphonate (^99mTc‐HDP) and PET/CT data with ¹⁸F‐fluoride were acquired up to 10 weeks after surgery. New bone formation was then confirmed by histology. Computed tomography scans allowed visualization of untreated bone defect healing; however, no information was gathered in presence of the ceramic. Positron emission tomography provided superior data compared with SPECT. The ¹⁸F‐fluoride uptake increased significantly up to 4 weeks after surgery, declining thereafter until the last time‐point. In vivo performances of porous versus dense ceramic scaffolds were also evaluated by PET, with a significantly higher uptake registered within the porous scaffolds. In conclusion, PET is a valuable tool for qualitative/quantitative follow‐up of bone healing around radiopaque bone substitutes in vivo. Copyright © 2014 John Wiley & Sons, Ltd.     

Does Radiofrequency Catheter Ablation Induce a Deterioration in Sympathetic Innervation? A Positron Emission Tomography Study

Radiofrequency catheter ablation (RFCA) is an effective treatment for the interruption of accessory bypass tracts in WPW syndrome or the modification of the Ay-nodal conduction system in patients with A V-nodal tachycardias. However RFCA may also damage cardiac innervation. The purpose of this pilot study was to assess possible changes in sympathetic innervation after RFCA as evaluated by the cathecholamine analog carbons-11- hydoxyephedrine (HED) positron emission tomography (PET) which allows the visualisation of sympathetic nerve terminals. We investigated nine patients with supraventricular tachycardias before and two to six weeks after RFCA. Myocardial perfusion was depicted by n-I3-ammonia-PET. In addition to visual analysis, HED retention was quantified in the myocardial quadrant distal to the location of intervention; these results were compared with values in remote areas. Before RFC A, myocardial perfusion showed homogenous distribution in 8 of 9 patients. One patient showed a perfusion defect in the posterior wall. HED retention matched perfusion distribution in all patients. After RF'CA there was no significant change observed either in ammonia or in HED distribution. Quantitative HED retention data showed no significant change before versus after RFC A. Thus, HED-PET does not demonstrate any abnormalities of tracer uptake indicating integrity of sympathetic nerve terminals after radiofrequency ablation therapy.     

FDG PET/CT of the non‐malignant liver in an increasingly obese world population

Because of obesity, non‐alcoholic fatty liver disease (NAFLD) is becoming increasingly important. 10% of NAFLD patients develop non‐alcoholic steatohepatitis (NASH), which may progress to cirrhosis and is now the leading indication for liver transplantation in the Western world. Prefibrotic NASH can only be reliably diagnosed by biopsy. However, given its success in other inflammatory diseases, PET/CT with ¹⁸F‐fluorodeoxyglucose (FDG), although non‐specific, may offer a promising approach to diagnosing not only NASH but also other inflammatory liver conditions. In addition, FDG PET has generated pathophysiological information on hepatic glucose metabolism and, diagnostically, used liver for quantification of tumour FDG accumulation (e.g. Deauville scoring). A review of hepatic FDG PET is therefore timely. There are two general approaches to the quantification of hepatic FDG accumulation: firstly, standard uptake value (SUV) and secondly dynamic PET. SUV is a poor index of hepatic metabolic function because most hepatic FDG (~75%) is un‐phosphorylated 60‐min postinjection. Hepatic fat is increased in NAFLD but accumulates negligible FDG. Because fat distribution is heterogeneous, maximum pixel SUV is therefore preferred to mean pixel SUV. Computer modelling of dynamic PET dissects the transport constants governing hepatic FDG kinetics but is challenged by the liver's dual blood supply. Graphical analysis is less informative but more robust and will be the preferred clinical approach to measurement of hepatic FDG phosphorylation. Previous dynamic PET studies have ignored hepatic fat and therefore potentially underestimated glucose accumulation in patients with hepatic steatosis. Future work should use graphical analysis of dynamic PET and correction for hepatic fat.     

Contraction-induced [18F]-fluoro-deoxy-glucose uptake can be measured in human calf muscle using high-resolution PET

Contraction-induced glucose uptake can be imaged and quantified by the use of positron emission tomography (PET). In the human extremities, such data may reveal important information regarding the in vivo mechanical function of e.g. the force transmitting tissues such as tendons. However, to investigate structures of limited size, a PET scanner with high resolution is required. We tested the potential of the recently developed high-resolution brain PET scanner (ECAT HRRT) for imaging of human lower extremities. [18F]-fluoro-deoxy-glucose uptake following voluntary and stimulated isometric muscle contractions was studied in a 30-year-old male. The results showed that the activated muscle or muscles are clearly delineated in the high-resolution PET images. Furthermore, the load-induced gain in tendon uptake was clearly visualized. In conclusion, the HRRT scanner is an appropriate tool for investigating physiological processes within the human extremities, and the very high resolution yields a potential for more accurate conclusions when target tissues are limited in size.     

18F-FDG PET/CT代谢指标预测胃肠道间质瘤恶性危险度

目的探讨¹⁸F-脱氧葡萄糖正电子发射计算机体层显像仪（¹⁸F-FDG PET/CT）代谢指标对胃肠道间质瘤（GIST）恶性危险度的预测价值。 方法回顾性分析2010年11月至2017年12月北京大学肿瘤医院44例GIST患者¹⁸F-FDG PET/CT术前显像及手术病理结果等临床病理资料。对于¹⁸F-FDG PET/CT显像阳性和阴性患者,应用χ²检验分析患者性别、年龄、病变部位、肿瘤直径、淋巴结转移、脏器转移、核分裂象、Ki-67指数、CD117和CD34表达、美国国立卫生研究院（NIH）危险度分级以及世界卫生组织（WHO）肿瘤预后分组等临床病理参数。对于¹⁸F-FDG PET/CT显像阳性患者,应用非参数秩和检验分析不同临床特征（性别、年龄、病变部位、肿瘤直径、病变密度、淋巴结或脏器转移情况）和不同病理特征（核分裂象、CD34表达情况、Ki-67指数、NIH危险度分级以及WHO肿瘤预后分组）患者3种PET/CT代谢指标,即最大标准摄取值（SUVmax）、肿瘤代谢体积（MTV）、病灶糖酵解总量（TLG）。采用Pearson相关分析分析SUVmax、MTV、TLG与GIST恶性危险度的相关性。 结果44例GIST患者中¹⁸F-FDG PET/CT显像阳性者31例,阴性者13例,显像阳性率为70.5%。显像阳性和显像阴性患者在肿瘤直径、核分裂象、Ki-67指数、NIH危险度分级、WHO肿瘤预后分组方面的差异均有统计学意义（χ²=13.926,P=0.003;χ²=7.738,P=0.021;χ²=4.233,P=0.040;χ²=24.670,P<0.001;χ²=24.670,P<0.001）,而在性别、年龄、病变部位、淋巴结转移、脏器转移、CD117和CD34表达方面差异均无统计学意义（P均>0.05）。31例¹⁸F-FDG PET/CT显像阳性者中,肿瘤直径≤5 cm患者与>5 cm患者比较,MTV（P=0.003）和TLG（P=0.004）的差异具有统计学意义,而SUVmax的差异无统计学意义（P>0.05）。核分裂象≤5/50HPF和>5/50HPF的患者,Ki-67指数≤5%和>5%的患者,以及不同NIH危险度分级、WHO肿瘤预后分组的患者,其SUVmax（P=0.022,0.023,0.016,0.016）、MTV（P=0.038,0.028,0.004,0.004）和TLG（P=0.025,0.014,0.004,0.004）的差异均具有统计学意义。不同性别患者,年龄≤60岁和>60岁患者,不同病变部位患者,不同病变密度患者,淋巴结或脏器有无转移的患者,以及不同CD34表达情况的患者,其SUVmax、MTV和TLG的差异均无统计学意义（P均>0.05）。行Pearson相关性分析显示,SUVmax（P=0.020,0.020,0.014,0.014）、MTV（P=0.037,0.026,0.003,0.003）和TLG（P=0.024,0.012,0.003,0.003）与核分裂象、Ki-67指数、NIH危险度分级、WHO肿瘤预后分组等病理学特征均具有相关性,差异具有统计学意义。SUVmax、MTV、TLG受试者工作特征曲线下面积分别为0.754、0.801和0.801。 结论¹⁸F-FDG PET/CT代谢指标SUVmax、MTV、TLG对GIST恶性危险度的分级有一定预测价值。     

Correlation of 18F-FDG PET/CT SUVmax with clinical features,D-dimer and LDH in patients with primary intestinal lymphoma

ObjectiveTo investigate the characteristics of fluorine-18-deoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) maximum standardized uptake value (SUVmax) in primary intestinal lymphoma (PIL) and its correlation with D-dimer and lactate dehydrogenase (LDH).MethodsFifty-two patients diagnosed with PIL from June 2016 to December 2019 were analyzed. All patients underwent 18F-FDG PET/CT. The relationships between SUVmax and different pathological subtypes, clinical stages and risk grades were analyzed. The correlations between SUVmax and Ki-67, LDH and D-dimer were determined. Additionally, PET/CT imaging results were collected from 35 patients with primary intestinal cancer (PIC) and compared with the imaging features of PIL.ResultsSUVmax was significantly different between PIL and PIC groups and various PIL pathological subgroups. Patients in the high-risk PIL group had markedly higher SUVmax values than the intermediate-risk and low-risk groups. A significant positive correlation was observed between SUVmax and Ki-67 in patients with PIL. SUVmax was significantly different between the elevated and normal D-dimer groups. D-dimer showed a positive correlation with SUVmax.Conclusion18F-FDG PET/CT SUVmax reflects the aggressiveness of lymphoma to a certain degree, is correlated with Ki-67 and determines the risk grades of PIL. Moreover, it facilitates differential diagnosis, clinical staging and treatment based on D-dimer levels.     

短暂性全面遗忘症的临床与PET成像研究

目的:研究短暂性全面遗忘症(transient global amnesia.TGA)患者脑代谢状况,并探讨其发病机理,方法:对3例临床下诊断为TGA的患者,分别行简易心理测试(MMSE)及脑核磁共振成像(MRI),在恢复后不同时间以18F标记的脱氧葡萄糖(18F-FDG)为示踪剂行脑正电子发射型计算机断层扫描(positron emission tomography,PET)成像,并对其图像与 病史进行对照研究.结果:3例患者MMSE测试及MRI扫描均未见异常,PET成像显著,1例正常,另外2例发现与记忆相关相关结构有不同程度的低代谢.结论:TGA的发病机制离缺血的病理生理过程,其脑代谢状况与症状持续时间密切相关,尽早终止其发作是必要的.     

中期18F-FDG PET/CT的评价方法在弥漫性大B细胞淋巴瘤预后预测中的价值

目的  探讨中期¹⁸F-FDG PET/CT的Deauville 5分法（Deauville 5-PS）、病灶与肝脏最大标准摄取值（SUV_max）的比值（LLR）、化疗前与化疗中期SUV_max的变化率（ΔSUV_max）3种评价方法在弥漫性大B细胞淋巴瘤（DLBCL）预后预测中的价值。方法  回顾性分析117例初治的DLBCL患者资料,采用Deauville 5-PS、LLR、ΔSUV_max对化疗中期PET/CT进行分析。采用ROC曲线计算LLR、ΔSUV_max预测患者无进展生存（PFS）和总生存（OS）的最佳临界值。采用Kaplan-Meier生存分析、单因素和多因素Cox比例风险回归模型对2年PFS率及OS率进行预后分析。结果  117例DLBCL患者中,疾病进展46例（39.3%）,死亡34例（29.1%）。Deauville 5-PS、LLR、ΔSUV_max分别以4分、1.81、75%为界值时,ΔSUV_max预测DLBCL患者PFS和OS的特异性、阳性预测值、准确度均高于LLR,LLR均高于Deauville 5-PS,但Deauville 5-PS预测DLBCL患者PFS、OS的敏感度最高。Deauville 5-PS < 4分组与≥4分组患者2年PFS率和OS率分别为80.8%和93.4%、49.3%和65.6%,差异有统计学意义（P < 0.001）;LLR < 1.81组与≥1.81组患者2年PFS率和OS率分别为82.4%和89.4%、27.2%和56.3%,差异有统计学意义（P < 0.001）。ΔSUV_max>75%与ΔSUV_max≤75%组患者2年PFS率和OS率分别为86.2%和93.1%、20.5%和48.9%,差异有统计学意义（P < 0.001）。单因素分析显示Deauville 5-PS、LLR、ΔSUV_max均是DLBCL患者PFS和OS的预后影响因素（P < 0.01）。多因素分析显示,ΔSUV_max和国际预后指数评分是DLBCL患者PFS、OS的独立危险因素。结论  中期PET/CT的Deauville 5-PS、LLR、ΔSUV_max3种评价方法均能预测DLBCL患者的预后,其中ΔSUV_max预测效能优于Deauville 5-PS和LLR,而且△SUV_max对DLBCL的预后具有独立预测价值。     

肥厚型心肌病患者18F-FDG PET心肌代谢显像与心脏MRI

目的 评价肥厚型心肌病（HCM）患者空腹及糖负荷状态下¹⁸F-FDG PET心肌葡萄糖代谢的变化。方法 对36例HCM患者行心脏MRI（CMRI）和空腹+糖负荷状态¹⁸F-FDG PET显像,对心肌代谢显像图像进行半定量评分。根据CMRI结果将患者分为延迟强化组（n=24）及无延迟强化组（n=12）,比较2组心肌代谢评分的差异。结果 空腹状态下延迟强化组左心室心肌代谢总评分较无延迟强化组明显减低;糖负荷状态下,2组代谢总评分差异无统计学意义。11例42个心肌节段在空腹状态下放射性摄取正常或增高,而糖负荷状态下放射性摄取稀疏或缺损,与其他25例比较,其室间隔厚度、左心室后壁厚度明显增加,延迟强化心肌节段数增多,左心室射血分数明显减低,差异均有统计学意义（P均<0.05）。结论 HCM患者空腹与糖负荷状态下¹⁸F-FDG PET心肌葡萄糖代谢显像表现出不均一性,结合CMRI,有望作为HCM患者危险度分层的指标。     

18F-FDG PET/CT显像在多发性骨髓瘤继发骨髓外浸润中的应用价值

目的:探讨多发性骨髓瘤继发髓外浸润的¹⁸F-FDG PET/CT图像特点,提高对该表现的认识。方法:回顾性分析2012年1月至2020年10月中国科学技术大学附属第一医院21例为穿刺病理或随访证实的多发性骨髓瘤继发髓外浸润患者,所有患者治疗前均行¹⁸F-FDG PET/CT显像,分析髓外浸润PET/CT显像特点。结果:21例患者中,男12例,女9例,年龄41-77岁,平均(58.3±10.0)岁;骨髓外浸润累及淋巴结9例,肺、胃、脾脏及肾脏各2例,腹膜后、右心耳、皮下结节及脊膜受累及各1例;髓外浸润SUVmax最大值21.2,最小值2.1,平均值7.7±5.3,骨髓病变最大值33.5,最小值2.4,平均值6.6±3.6,髓外浸润与骨髓病变SUVmax比较,二者之间差异无统计学意义(Z=-1.195,P=0.232)。结论:¹⁸F-FDG PET/CT不仅对多发性骨髓瘤有很好的诊断价值,而且对继发髓外浸润也有很好的评估价值,为临床治疗及预后判断提供了一定的参考。     

PET/CT在直肠癌术后放化疗患者癌灶远端转移诊断及预后评估中的应用

目的  探究PET/CT在直肠癌术后放化疗患者癌灶远端转移诊断及预后评估中的应用效果。方法  回顾性分析我院2019年3月~2020年3月70例直肠癌手术患者的资料,所有患者术后均进行放化疗辅助治疗,并采用PET/CT检测治疗效果,根据治疗后是否出现复发、转移评估患者预后,以病理学检测为金标准,比较CT、PET/CT对直肠癌患者癌灶远端转移的诊断价值;将复发、转移者纳入复发转移组（n=26）,无复发转移者纳入预后良好组（n=44）,对比两组的临床资料;采用多因素Logistic回归分析影响直肠癌患者术后放化疗患者预后的相关因素。结果  70例患者中,术后3年经病理诊断癌灶远端转移阳性21例,阴性49例,CT诊断癌灶远端转移阳性22例,阴性48例,其中漏诊4例,误诊5例,诊断敏感度为80.95%,特异性为88.37%,准确率为87.14%,阳性预测值为77.27%,阴性预测值为91.67%,Kappa值为0.698;PET/CT诊断远端转移阳性23例,阴性47例,其中漏诊2例,误诊4例,诊断敏感度为90.47%,特异性为91.84%,准确率为91.43%,阳性预测值为82.61%,阴性预测值为95.74%,Kappa值为0.801;复发转移组年龄、病灶最大直径、TNM分期、最大标准化摄取值（SUV_max）、最小标准化摄取值（SUV_min）、滞留指数（RI）均高于预后良好组（P＜0.05）,两组性别、BMI、病理类型比较,差异无统计学意义（P＞0.05）;多因素Logistic回归分析显示,年龄、病灶最大直径、TNM分期、SUV_max值、SUV_min值、RI值是影响直肠癌患者术后放化疗预后的危险因素（P＜0.05）。结论  PET/CT技术对直肠癌术后放化疗患者癌灶远端转移诊断价值较高,且其诊断参数SUV_max值、SUV_min值、RI值是影响患者术后放化疗预后的危险因素,可用于临床术后复发转移预测。     

利用PET-CT对脑卒中早期康复训练的脑皮质功能区重组研究

目的：探讨脑卒中早期康复训练后脑功能区重组的规律。方法：发病1个月内的脑卒中偏瘫患者8例志愿者分为两组：康复治疗组6例,康复治疗时间1个半月,对照组2例(因个人经济原因未能接受康复治疗);发病初和1个月末分别进行PET-CT扫描、 Fugl-Meyer评价、Barthel指数及神经功能缺损的测定。结果：8例脑卒中患者第一次扫描的健侧与患侧总均值有显著性差异（P<0.01）,主要为初级运动区(M1)、后顶叶皮质(PPC)、小脑、辅助运动区(SMA)（P<0.01）,治疗组与对照组无明显差异（P>0.05）;两次同侧比较,健侧总均值与治疗组第二次有明显差异（P<0.05）;患侧总均值与治疗组第二次有显著性差异（P<0.01）。第二次各组内两侧比较,治疗组均有显著性差异（P<0.01）;对照组有明显差异（P<0.05）;第二次两组间比较：健侧各功能区有明显差异（P<0.05）,而两组患侧除M1无明显差异（P>0.05）外,其余各功能区有明显差异（P<0.05）。结论：卒中早期以健侧半球代偿为主导, 运动相关区在皮质功能重组中异常活跃, 脑卒中康复治疗后皮质激活区有向患侧半球转移的趋势,功能训练有利于皮质功能重组。