晚期帕金森病患者^18F—脱氧葡萄糖PET脑影像学特征的研究

目的探讨晚期帕金森病(PD)患者静止期18F-脱氧葡萄糖(FDG)PET的脑影像学特征及其意义.方法对8例双侧症状的晚期帕金森病患者(男5例,女3例;平均年龄64.5±3.7岁;H-Y分级4.1±0.5)和8例正常人(对照组),经静脉注射FDG后行脑造影断层显像,获得脑局部葡萄糖代谢图像,通过SPM99统计学软件进行数据分析,比较两组之间脑内代谢的差异.结果与正常人相比,帕金森病患者双侧丘脑、中央前回皮质(BA6)以及豆状核代谢增加(P＜0.001);前额叶运动区(BA46)以及顶枕部代谢减低(P＜0.001).结论帕金森病患者丘脑、豆状核代谢增加,其相应的前额叶运动区以及顶枕部代谢减低,帕金森病的这一脑内代谢特点有助于帕金森病的辅助诊断及对其发病机制的探讨.     

晚期帕金森病患者~(18)F-脱氧葡萄糖PET脑影像学特征的研究

目的　探讨晚期帕金森病 (PD)患者静止期 1 8F-脱氧葡萄糖 (FDG) PET的脑影像学特征及其意义。方法　对 8例双侧症状的晚期帕金森病患者 (男 5例 ,女 3例 ;平均年龄 64.5± 3.7岁 ;H- Y分级 4.1± 0 .5)和 8例正常人 (对照组 ) ,经静脉注射 FDG后行脑造影断层显像 ,获得脑局部葡萄糖代谢图像 ,通过 SPM99统计学软件进行数据分析 ,比较两组之间脑内代谢的差异。结果　与正常人相比 ,帕金森病患者双侧丘脑、中央前回皮质 (BA6)以及豆状核代谢增加 (P<0 .0 0 1 ) ;前额叶运动区 (BA46)以及顶枕部代谢减低 (P<0 .0 0 1 )。结论　帕金森病患者丘脑、豆状核代谢增加 ,其相应的前额叶运动区以及顶枕部代谢减低 ,帕金森病的这一脑内代谢特点有助于帕金森病的辅助诊断及对其发病机制的探讨。     

~(18)F氟脱氧葡萄糖正电子发射断层显像鉴别阿尔茨海默病和额颞叶痴呆的价值

目的探讨~(18)F-氟脱氧葡萄糖(~(18)F-FDG)正电子发射断层显像(positron emission tomography,PET)/CT对阿尔茨海默病(AD)和额颞叶痴呆(FTD)的鉴别诊断价值。方法回顾性分析临床诊断为AD 20例和FTD 10例的~(18)F-FDG PET/CT脑代谢显像资料,采用脑代谢影像进行视觉分析,测量相应部位的标准摄取值(standard up take value,SUV),以小脑为参考脑区,以放射性摄取减低脑区的SUV与小脑SUV的比值(SUVr)表示。采用NeuroQ脑分析软件进行定量分析其代谢模式特点。结果 20例AD患者视觉分析显示,16例(80.0%)伴有双侧顶叶代谢减低,8例(40.0%)伴有双侧颞叶代谢减低,5例(25.0%)伴有单侧额叶代谢减低,2例(10.0%)伴有单侧颞叶代谢减低;定量分析显示,全部患者(100.0%)均伴有双侧顶叶代谢减低,18例(90.0%)伴有后扣带回代谢减低,17例(85.0%)伴有双侧颞叶代谢减低,7例(35.0%)伴有单侧额叶代谢减低。10例FTD患者视觉分析显示,8例(80.0%)患者伴有颞叶代谢减低,6例(60.0%)患者伴有额叶代谢减低,3例(30.0%)伴有双侧顶叶代谢减低;定量分析显示,10例患者(100.0%)均伴有额叶代谢减低,8例(80.0%)伴有颞叶代谢减低,4例(40.0%)伴有双侧顶叶代谢减低,4例(40.0%)伴有基底节代谢减低,3例(30.0%)伴有后扣带回代谢减低。AD患者和FTD患者额叶、顶叶和颞叶SUVr比较,差异有统计学意义(1.08±0.13 vs 0.75±0.09,0.78±0.14 vs 1.06±0.05,0.81±0.14 vs 0.95±0.12,P<0.01)。结论 ~(18)F-FDG PET/CT脑显像显示的AD和FTD患者不同的代谢减低模式,有助于临床进行鉴别诊断。     

18F-FDG PET脑显像SPM分析法在颞叶内侧癫痫术前定位中的价值

目的探讨18F-FDG PET脑显像像素统计参数图（SPM）法在颞叶内侧癫痫术前定位中的价值。方法对17例颞叶内侧癫痫患者行脑18F—FDG PET检查,对其所有PET图像进行感兴趣区（ROI）法及SPM分析法比较。SPM分析法所用健康对照组选自同期于本中心健康查体者20例。结果ROI法对癫痫灶准确定侧率为70．6％,准确定位率为29．4％;SPM法分别为70．6％、47．1％。二者准确定位率比较,P〈0．05。SPM法发现双侧颞叶代谢异常9例（52．9％）,伴额、顶叶皮层代谢异常者12例（70．6％）。结论18F-FDG PET脑显像SPM法是一种简便、客观、有效的颞叶癫痫灶定位方法,且有助于发现脑代谢异常。     

18F-脱氧葡萄糖单光子发射计算机断层显像鉴别阿尔茨海默病及额颞叶痴呆的临床研究

目的 探讨阿尔茨海默病(Alzheimers disease,AD)及额颞叶痴呆(Frontotemporal dementia,FTD)患者18 F-脱氧葡萄糖(18F-deoxyglucose,18F-FDG)单光子发射计算机断层显像(SPECT)的特点。方法 选择2014年12月~2015年10月在首都医科大学宣武医院核医学科就诊并诊断为AD和FTD的患者29例,按诊断分为AD组19例,其中男性8例,女性11例,平均年龄(61.57±7.46)岁;FTD组10例,其中男性6例,女性4例,平均年龄(62.80±7.53)岁。同期选健康老年人9例为对照组,其中男性4例,女性5例,平均年龄(60.11±10.79)岁。所有研究对象行18F-FDG的SPECT检查。结果 对照组双侧大脑皮质、丘脑和基底节区未见异常放射性浓聚、稀疏或缺损。AD组和FTD组患者与对照组相比,18F-FDG的SPECT检查均表现为皮质代谢减低。AD组15例双侧大脑皮质对称性减低,其中40.00%顶、颞叶皮质代谢对称性明显减低;33.3%双侧顶叶皮质代谢对称性明显减低;13.33%伴有双侧额叶皮质代谢对称性减低。FTD组8例对称性减低,其中50%双侧额叶皮质代谢对称性明显减低。Fisher确切概率法检验显示,AD组和FTD组患者的SPECT脑代谢表现具有显著统计学差异(P0.05)。结论18F-FDG的SPECT能够为临床鉴别诊断AD和FTD提供客观的影像学依据。     

帕金森病不同临床阶段静态脱氧葡萄糖代谢模式的正电子发射断层扫描

目的研究帕金森病(PD)在不同临床阶段脱氧葡萄糖(FDG)代谢特征和变化过程。方法对33例PD患者(PD组)以及8例无神经系统疾病患者(正常对照组)进行了18F-FDG-正电子发射断层扫描(PET)检查。PD患者中H-Y分期:Ⅰ期3例,Ⅱ期18例,Ⅲ期10例,Ⅳ期2例。分别取豆状核、尾状核、丘脑、小脑、双侧额叶、双侧顶叶、双侧颞叶和双侧枕叶为感兴趣区(ROI)进行放射性显像强度比较。结果与正常对照组比较,PD组不同临床阶段FDG代谢的共同点是:颅内结构FDG脑代谢呈现不对称性,以豆状核代谢不对称为主;丘脑、尾状核、额顶叶交界区FDG代谢降低;豆状核代谢高于尾状核以及丘脑。随着病情进展FDG脑代谢逐渐变化:H-YⅠ期时症状首发肢体对侧豆状核代谢高于同侧豆状核,H-YⅡ~Ⅳ期时症状首发肢体同侧豆状核代谢也逐渐增高接近于对侧的豆状核;H-YⅠ期的额顶交界区皮质代谢降低,Ⅱ、Ⅲ期低代谢范围逐渐扩大,Ⅳ期则发展到额、顶、颞叶广泛低代谢。结论PD的FDG代谢随着病情进展既有共性,也有不同的特征性改变。这种FDG代谢的变化有助于PD的诊断和鉴别诊断。     

头部MRI及PET检查对进行性核上性麻痹与帕金森病的诊断价值

目的探讨头部磁共振成像(MRI)及以18F-脱氧葡萄糖(18F-FDG)为示踪剂的正电子发射计算机断层扫描(PET)两种影像学检查对进行性核上性麻痹(PSP)及帕金森病(PD)的诊断价值。方法对2004年8月至2006年11月在首都医科大学附属北京天坛医院神经内科就诊的11例PSP和178例PD患者进行常规头部MRI检查,并对其中5例PSP和48例PD患者进行18F-FDGPET检查。结果(1)MRI检查:11例PSP患者均可见矢状位T1加权像有中脑上缘平坦或者凹陷表现,PD组未见上述表现;正中矢状位T1加权像上计算中脑截面面积,PSP组低于PD组,差异有显著性意义(P<0.01)。(2)18F-FDGPET检查:PSP组主要表现为对称性额叶低代谢,纹状体代谢基本对称。PD组主要表现为顶叶代谢略低于额叶前部,首发症状肢体对侧顶叶代谢降低明显;纹状体呈不对称表现,首发症状肢体同侧纹状体代谢降低,对侧纹状体后部代谢降低;纹状体代谢高于同侧丘脑。结论MRI及18F-FDGPET检查对诊断PSP在中脑形态学改变(中脑萎缩)及脑葡萄糖低代谢方面有特异性,与PD组比较差异有显著性意义。     

皮质基底节综合征临床及影像学分析

目的 探讨皮质基底节综合征(CBS)的临床及影像学特征.方法 选择2017年7月～2021年4月我院神经内科门诊和病房就诊的CBS患者20例,依据18F氟脱氧葡萄糖(18F-FDG)正电子发射断层显像(PET)的脑代谢模式分为阿尔茨海默病(AD)源性CBS(CBS-AD)组8例和非CBS-AD组12例,用简易智能状态检...     

18F-FDG PET/CT分子显像评价缺血性心脏病患者心功能受损与脑葡萄糖代谢的相关性研究

目的从细胞能量代谢的角度评价缺血性心脏病(IHD)患者左心室功能受损与脑葡萄糖代谢水平之间的关系,探索心功能受损患者脑葡萄糖代谢减低的功能区。方法入选于2016年4月至2017年10月在北京安贞医院行99Tcm-甲氧基异丁基异腈(MIBI)门控单光子发射计算机断层扫描/CT(SPECT/CT)心肌灌注显像、18F-脱氧葡萄糖(FDG)门控正电子发射计算机断层成像/CT(PET/CT)心肌葡萄糖代谢显像和脑葡萄糖代谢显像(于3 d内完成所有检查)的IHD患者110例。采用QGS软件分析门控SPECT/CT心肌灌注显像和门控PET/CT心肌葡萄糖代谢显像数据,获取左心室功能参数,包括舒张末期容积(EDV)、收缩末期容积参数(ESV)和左心室射血分数(LVEF)。采用17段-5分法判断心肌存活和心肌梗死,并计算心肌存活范围及心肌梗死范围。根据心肌存活范围将患者分为存活心肌<10%组(44例)、存活心肌10%~<20%组(36例)和存活心肌≥20%组(30例)。采用Pearson相关系数分析心肌存活范围及心肌梗死范围等影像参数与脑葡萄糖代谢水平之间的相关性。采用脑代谢定量分析软件SPM评估全脑葡萄糖代谢标准摄取值的平均值(SUVmean)与小脑葡萄糖代谢SUVmean,并计算靶本比值全脑/小脑(TBR全脑/小脑),即全脑葡萄糖代谢SUVmean与小脑葡萄糖代谢SUVmean的比值。采用SPM软件评估3组之间不同脑功能区脑葡萄糖代谢水平的差异。结果男性101例,年龄(57±10)岁。TBR全脑/小脑与存活心肌范围、梗死心肌范围、门控SPECT/CT及门控PET/CT测得的LVEF有相关性(r值分别为0.280、-0.329、0.188、0.215,P均<0.05)。存活心肌<10%组患者的TBR全脑/小脑为(1.25±0.97),明显低于存活心肌10%~<20%组的1.32±0.17(P<0.05)和存活心肌≥20%组的1.34±0.16(P<0.05)。SPM分析发现,与存活心肌≥20%组比较,存活心肌<10%组患者的楔前叶、额叶、中央后回、顶叶、颞叶等脑功能区的脑葡萄糖代谢水平明显减低。结论IHD患者的左心室功能受损与脑葡萄糖代谢水平存在相关性。心肌存活量少的IHD患者,全脑葡萄糖代谢水平减低,且主要集中在与认知功能相关的脑功能区。     

非霍奇金淋巴瘤患者脑葡萄糖代谢改变的统计参数图分析

目的探讨非霍奇金淋巴瘤(NHL)患者脑葡糖糖代谢改变的特点。方法回顾性分析解放军总医院2015年1月至2016年5月95例未经治疗的体部NHL患者和60例健康体检者脑部~(18)氟-脱氧葡萄糖(~(18)F-FDG)正电子发射计算机断层显像(PET/CT)图像,通过统计参数图(SPM)软件在一定显著性水平(P0.001)和体素阈值(K=125体素)下分析NHL患者与60例健康体检者、以及14例60岁和81例≤60岁NHL患者脑部葡萄糖代谢改变的特征和脑区分布。结果与对照组相比,NHL患者未发现代谢增高的脑区,但存在多个脑区的葡萄糖代谢减低,减低区主要位于部分双侧枕叶、左侧额下回、双侧中央前回,且左侧葡萄糖代谢减低区域的范围较右侧更广泛。60岁NHL组和≤60岁NHL组相比,60岁NHL患者脑部葡萄糖代谢出现减低区和增高区,减低区主要存在于双侧额叶,增高区主要存在于双侧小脑。结论 NHL患者脑葡糖糖代谢减低并非全脑性分布,而是以区域性葡萄糖代谢减低为特征,涉及脑区可能与患者的精神情感功能及免疫改变有关。60岁NHL患者葡萄糖代谢减低区域更广泛,可能与脑老化改变相关。     

进行性核上性麻痹的临床表现和神经影像学特点

目的探讨进行性核上性麻痹(progressive supranuclear palsy,PSP)的临床特点及头颅MRI、正电子发射体层扫描(PET)检查在本病中的诊断价值。方法回顾性分析19例PSP患者临床特点、神经影像学特征。结果19例PSP患者中,12例患者以走路不稳、反复向后跌倒为首发.17例患音出现垂直性核上性眼肌麻痹,假性球麻痹出现较早,还伴有轴性肌张力障碍、轻度痴呆等症状。19例患者均行头颅MRI检查,10例患者正中矢状位可见中脑上端萎缩,呈"蜂鸟征",水平位可见中脑前后径变小,呈"鼠耳征",1例患者中脑被盖和顶盖部T_2加权像显示弥散性高信号,中脑萎缩随病程加重。13例患者PET检查,均可见中脑葡萄糖代谢降低,双侧额叶葡萄糖代谢降低比较明显,部分合并顶叶或顶枕联合区葡萄糖代谢降低。结论 PSP临床表现变异较大,但通过头颅MRI、PET等辅助检查的特征性表现,可为诊断及鉴别诊断提供依据。     

Positron emission tomography in patients with fibromyalgia syndrome and healthy controls

OBJECTIVE: Abnormal brain findings have previously been described in fibromyalgia syndrome (FMS) by single-photon-emission computed tomography. Our goal was to investigate change in regional cerebral glucose metabolism in people with FMS by positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG). METHODS: Twelve patients with FMS and no comorbid psychiatric diagnosis and 7 healthy pain-free controls were studied with FDG-PET in a blinded manner. Those with a psychiatric diagnosis were excluded. Brain scans were obtained using a PET scanner. Semiquantitative analysis of regional 18F-FDG uptake was performed in both cortical and subcortical brain structures. RESULTS: In the resting state, there were no significant differences in 18F-FDG uptake between patients and controls for all brain structures measured. CONCLUSION: FDG-PET scan findings in FMS were not significantly different from healthy controls. Normal results in our study may be explained by discordance between regional cerebral blood flow and regional cerebral glucose metabolism.     

Comparison of perfusion 18F-FP-CIT PET and 99mTc-ECD SPECT in parkinsonian disorders

Early and accurate identification of various conditions that can cause parkinsonian symptoms is important for determining treatment policies. Currently dopamine transporter (DAT) imaging using FP-CIT, glucose metabolism imaging using fluorodeoxyglucose, cerebral blood flow image using ethyl cysteinate dimer (ECD), and others are used for differentiation. However, the use of multiple modalities is inconvenient and costly. In the present retrospective study, we evaluated the correlation between regional brain uptake ratios (URs) in perfusion FP-CIT PET and ECD SPECT images.Twenty patients with Parkinson''s symptoms underwent perfusion DAT positron emission tomography (¹⁸F-FP-CIT PET/CT) and cerebral blood flow tomography (^99mTc-ECD SPECT) within a 2-week period. Perfusion ¹⁸F-FP-CIT PET/CT and ^99mTc-ECD SPECT URs of 19 brain regions (bilateral frontal, temporal, parietal and occipital lobes, bilateral caudate nucleus, bilateral putamen, bilateral insula, bilateral cingulate gyrus, bilateral thalamus, and brainstem) were directly compared and correlations were analyzed.Average ¹⁸F-FP-CIT PET/CT regional perfusion URs were higher than ^99mTc-ECD SPECT URs. Uptake ratios were well correlated in all 19 regions (except right putamen), and especially in dopamine poor regions (cerebral cortex). In left putamen, URs were significantly correlated, but the correlation coefficient was lower than those of other regions.A single tracer dual phase N-3-fluoropropyl-2-beta-carboxymethoxy-3-beta-(4-iodophenyl) nortropane test seems to be helpful for differential diagnosis of parkinsonian disorders. Large-scale, longitudinal studies on complementary diseases with parkinsonian patterns are required to investigate differences in correlations between perfusion ¹⁸F-FP-CIT PET/CT and ^99mTc-ECD SPECT over time.     

FDG-PET findings in patients with galactosaemia

Summary  Despite treatment with a galactose-restricted diet, many galactosaemia patients develop lifelong cognitive impairment, speech abnormalities and a gamut of neurological problems including cognitive impairment and tremors. No study has explored changes in cerebral glucose metabolism in patients with galactosaemia. Five patients with galactosaemia had ages ranging from 20 to 40 years (mean age 28 years) and eight similarly aged controls received brain [¹⁸F]fluorodeoxyglucose (FDG) positron emission tomography (PET) scans. PET scans were analysed using a previously validated template methodology of regions of interest (ROIs). Count ratios for each anatomical ROI were compared between the galactosaemic patients and the healthy controls. Statistical parametric mapping (SPM) software was also used to further analyse the data. ROI analysis showed that galactosaemic patients had significant bilateral decreases in cerebral glucose metabolism in the superior temporal gyrus, medial occipital lobe, parietal lobe, cerebellum, calcarine cortex, superior frontal cortex, and superior parietal cortex when compared with controls. Significant increases were seen in the cingulate gyrus and temporal poles, bilaterally. SPM analysis revealed foci of decreased glucose metabolism in the caudate, cerebellum, precentral gyrus and cerebellar tonsils of galactosaemic patients. SPM also showed increased glucose metabolism in the subcallosal gyrus and claustrum. The results show significant abnormalities in cerebral function in patients with galactosaemia, particularly with widespread decreases in cortical metabolism. These abnormalities appear to be in brain regions that may be associated with the neuropsychological deficits in these patients. PET brain scans may be of value in galactosaemia patients to evaluate for dysfunction. S. Segal deceased. Competing interests: None declared     

Functional Imaging of the Brain in Patients with Liver Cirrhosis

Brain imaging techniques have provided substantial insight into the pathophysiology of hepatic encephalopathy (HE). Magnetic resonance imaging gave hint to the fact that there is an increased deposition of manganese especially in the basal ganglia. Single photon emission computed tomography (SPECT) and positron emission tomography (PET) showed that the preference of the basal ganglia might be due to differences in regional cerebral blood flow and an additional redistribution of blood flow from the cortex to subcortical regions in cirrhotics. PET studies using ammonia as tracer showed that the cerebral metabolism of ammonia and the permeability of the blood brain barrier for ammonia is increased in cirrhotic patients compared to healthy controls. The regional ammonia supply is in accordance with the regional blood flow. In accordance with these findings fluorodesoxyglucose-PET-studies of the brain in cirrhotics showed characteristic alterations of glucose utilisation in the patients with a relative decrease of the glucose utilisation of the cingulate gyrus, the frontomedial, frontolateral, and parieto-occipital cortex, while the glucose utilisation of the basal ganglia, the hippocampus, and the cerebellum was relatively increased. These findings fit well with the clinical characteristics of early stages of HE such as deficits in attention, visuo-spatial orientation, visuo-constructive abilities, motor speed, and accuracy.     

Metabolic restaging of hepatocellular carcinoma using whole-body 18F-FDG PET/CT

AIM: To evaluate the ability of ¹⁸F-fluorodeoxyglucose positron emission and computed tomography (¹⁸F-FDG PET/CT) in restaging of hepatocellular carcinoma (HCC) after treatment.METHODS: We reviewed a database of the diagnostic performance of ¹⁸F-FDG PET/CT scan for patients with HCC following local or regional treatment. The database consisted of ¹⁸F-FDG PET/CT information of 21 male and 4 female (age range, 27-81 years; mean age, 51.6 years) patients who had received surgical resection and/or interventional treatments and then underwent ¹⁸F-FDG PET/CT scan. All patients had received enhanced CT scan of the liver two weeks before or after the ¹⁸F-FDG PET/CT scan. Intrahepatic recurrence and/or extrahepatic metastases were confirmed by histological analysis or clinical and imaging follow-up. The accuracy of ¹⁸F-FDG PET/CT study was determined by histopathological results or by clinical and imaging follow-up.RESULTS: ¹⁸F-FDG PET/CT was abnormal in 19 of the 25 (76.0%) patients. In detecting HCC recurrence, ¹⁸F-FDG PET/CT scored 17 true positives, 5 true negatives, 2 false positives and 1 false negative. The sensitivity, specificity and accuracy of ¹⁸F-FDG PET/CT in detecting HCC recurrence was 89.5%, 83.3% and 88%, respectively. ¹⁸F-FDG PET/CT had an impact on management of these patients by settling the problem of an unexplained increase in alpha-fetoprotein after treatment (14 patients), by monitoring response to the treatment and guiding additional regional therapy (12 patients), by identifying extrahepatic metastases (10 patients), by identifying tumor growth or thrombosis in the portal vein (6 patients), or by guiding surgical resection of extrahepatic metastases (2 patients).CONCLUSION: Our results suggest that whole body ¹⁸F-FDG PET/CT may be useful in the early evaluation of residual, intrahepatic recurrent or extrahepatic metastatic lesions and able to provide valuable information for the management of HCC recurrence.     

Resting cerebral blood flow alteration in severe obstructive sleep apnoea: an arterial spin labelling perfusion fMRI study

Study objectives

The aim of this study is to investigate changes in regional cerebral blood flow (rCBF) in awake people with untreated severe obstructive sleep apnoea (OSAs) compared with good sleepers (GSs).

Design

Arterial spin labelling perfusion imaging was used to quantify cerebral perfusion based on resting-state functional magnetic resonance imaging (MRI).

Setting

Lying supine in a 3.0-T magnetic resonance imaging scanner in the night was done.

Participants

Included in this study were 30 subjects with OSA (males; mean age 38.4 years, range 25–55) and 30 controls (males; mean age: 38.3 years, range 26–52) matched for age and years of education.

Results

Compared with GSs, participants with severe OSA had reduced rCBF in the left cerebellum posterior lobe, left temporal lobe, right medial frontal gyrus, and bilateral parahippocampal gyrus and increased rCBF in the bilateral superior frontal gyrus. The lower mean CBF in the right parahippocampal gyrus exhibited a significant positive correlation with arousal index (r = 0.365, P = 0.047). The increased mean CBF in the left superior frontal gyrus exhibited a significant positive correlation with the longest apnoea time (r = 0.422, P = 0.020), and the increased mean CBF in the right superior frontal gyrus exhibited a significant positive correlation with the longest apnoea time (r = 0.447, P = 0.013).

Conclusions

Our results show that the altered rCBF pattern in the left cerebellum posterior lobe, left temporal lobe, left medial frontal gyrus, bilateral parahippocampal gyrus and superior frontal gyrus in patients have with severe OSA. The arterial spin labelling perfusion imaging method is a useful non-invasive imaging tool for detection of early changes in the regional cerebral blood flow in patients with OSA.

     

Positron emission tomography reveals correlations between brain metabolism and mood changes in hyperthyroidism

CONTEXT: Hyperthyroidism is frequently associated with emotional distress. The underlying cerebral processes of the endocrine-induced mood changes are unclear. OBJECTIVE: The objective of this study was to investigate, for the first time, the neuronal correlates of thyrotoxicosis-associated psychic symptoms using positron emission tomography (PET). DESIGN: The study was designed as a cross-sectional trial. SETTING: The study was performed at joint nuclear medicine and thyroid clinics. PATIENTS: Twelve patients with untreated Graves' hyperthyroidism were evaluated. METHODS: Levels of emotional distress were self-rated by means of the Hospital Anxiety and Depression Scale. Both patients and 20 age- and gender-matched euthyroid controls underwent a brain fluorodeoxyglucose PET scan. Subsequently, the functional relationship between brain metabolism and the psychometric scores was analyzed. RESULTS: Compared with controls and visualized by fluorodeoxyglucose PET, hyperthyroid patients showed a decreased (P < 0.0001) glucose metabolism in the limbic system (uncus and inferior temporal gyrus). Activation foci in the posterior cingulate and in the inferior parietal lobe were correlated with both anxiety and depression scales (P < 0.001). Compared with patients with normal anxiety levels, those with increased anxiety yielded an enhanced glucose metabolism (P < 0.001) in the bilateral sensory association cortex. Serum free T3/free T4 levels negatively correlated with regional glucose metabolism in the medial posterior cingulate. CONCLUSIONS: Thyrotoxicosis and associated psychic symptoms are correlated to regional metabolic changes in the main structures of the limbic/paralimbic system.     

Positron Emission Tomography With 18F-Fluorodeoxyglucose in Patients With Sickle Cell Acute Chest Syndrome

The acute chest syndrome (ACS) is the main cause of mortality among adult patients with sickle cell disease (SCD). Its pathophysiology is still unclear. Using positron emission tomography (PET) with ¹⁸F-fluorodeoxyglucose [18F-fluorodeoxyglucose (¹⁸F-FDG)], we explored the relationship between regional lung density and lung metabolism, as a reflection of lung neutrophilic infiltration during ACS.Patients were prospectively enrolled in a single-center study. Dual modality chest PET/computed tomography (CT) scans were performed, with ¹⁸F-FDG emission scans for quantification of regional ¹⁸F-FDG uptake and CT scans with radiocontrast agent to check for pulmonary artery thrombosis. Regional lung ¹⁸F-FDG uptake was quantified in ACS patients and in SCD patients without ACS (SCD non-ACS controls). Maximal (SUVmax) and mean (SUVmean) standardized uptake values were computed.Seventeen patients with ACS (mean age 28.3 ± 6.4 years) were included. None died nor required invasive mechanical ventilation. The main lung opacity on CT scans was lower lobe consolidation. Lungs of patients with ACS exhibited higher SUVmax than those of SCD non-ACS controls (2.5 [2.1–2.9] vs 0.8 [0.6–1.0]; P < 0.0001). Regional SUVmax and SUVmean was higher in lower than in upper lobes of ACS patients (P < 0.001) with a significant correlation between lung density and SUVmax (R² = 0.78). SUVmean was higher in upper lobes of ACS patients than in lungs of SCD non-ACS controls (P < 0.001). Patients with SUVmax >2.5 had longer intensive care unit (ICU) stay than others (7 [6–11] vs 4 [3–6] days; P = 0.016).Lungs of patients with ACS exhibited higher ¹⁸F-FDG uptake than SCD non-ACS controls. Lung apices had normal aeration and lower ¹⁸F-FDG uptake than lung bases, but higher ¹⁸F-FDG uptake than lungs of SCD non-ACS controls. Patients with higher lung ¹⁸F-FDG uptake had longer ICU stay than others.