MSCT多种测量方法在上颈椎椎弓根测量中的应用价值

目的 :探讨MSCT不同测量方法在上颈椎椎弓根测量中的应用价值。方法 :选择51例怀疑或确诊为上颈椎病变患者行颈部CT检查。通过MIP、MPR和VR等后处理方式分别显示椎体、椎弓根及周围的解剖结构。在MPR、MIP和VR图像上分别测量C2椎弓根宽度(PW),椎弓根的长度(PL),椎弓根高度(PH),头倾角(PSA)和内倾角(PMA)。由1名主管技师独立对3种方法测量的数值差异、可操作性及显示能力进行比较分析。结果:MPR、MIP和VR 3种方式均能很好地显示椎体、椎弓根及周围的解剖结构和彼此的空间位置关系。MPR、MIP和VR 3种方法测定的C2椎弓根数据是:1MPR:PW(右/左)为(5.43±1.62)mm/(5.43±1.53)mm,PL(右/左)为(25.66±3.79)mm/(26.57±3.76)mm,PH(右/左)为(9.18±2.20)mm/(9.08±2.34)mm,PSA(右/左)为(31.79°±9.57°)/(32.13°±9.96°),PMA(右/左)为(31.14°±10.22°)/(32.69°±10.57°)。2 MIP:PW(右/左)为(6.04±1.62)mm/(6.11±1.66)mm,PL(右/左)为(28.59±3.76)mm/(28.95±3.79)mm,PH(右/左)为(9.52±2.13)mm/(9.19±2.10)mm,PSA(右/左)为(28.73°±11.00°)/(29.88°±2.82°),PMA(右/左)为(35.78°±11.84°)/(35.68°±12.30°)。3 VR:PW(右/左)为(6.82±1.75)mm/(6.52±1.92)mm,PL(右/左)为(28.28±3.93)mm/(28.40±3.76)mm,PH(右/左)为(9.64±1.73)mm/(9.33±2.13)mm,PSA(右/左)为(31.82°±8.81°)/(29.12°±2.33°),PMA(右/左)为(34.00°±11.28°)/(36.43°±11.90°)。左右椎弓根数据间差异均无统计学意义。3种测量方法两两之间行配对t检验,MPR与MIP在评价PL、PW和PMA(右)上差异均有统计学意义(均P<0.05),MPR与VR在评价PL、PW和PSA(右)上差异均有统计学意义(均P<0.05),MIP与VR在评价PW和PSA(右)上差异均有统计学意义(均P<0.05);其余数据差异无统计学意义(P>0.05)。结论 :MSCT 3种测量方法均可以用于上颈椎椎弓根数据的测量,为上颈椎后路内固定置钉提供参考,在实际工作中,可根据需要采用不同的测量方法。     

脑小血管病丘脑的1H-MRS成像特点及其与认知功能相关性研究

目的 探讨脑小血管病(CSVD)患者丘脑的代谢变化特点,了解其与认知障碍间的关系.方法 采用蒙特利尔认知评估量表(MoCA)对34例CSVD患者和26例志愿者进行认知功能测评,通过单体素氢质子磁共振波谱(1H-MRS)技术对所有研究对象两侧丘脑N-乙酰基天门冬氨酸(NAA)、胆碱化合物(Cho)、磷酸肌酸(Cr)的含量进行检测,记录NAA/Cr、Cho/Cr比值.比较2组间两侧丘脑NAA/Cr、Cho/Cr比值的差异,并对CSVD组内两侧丘脑NAA/Cr、Cho/Cr比值与MoCA总评分及各子项评分进行相关性分析.结果 ①CSVD组MoCA总评分、视空间与执行能力、记忆、注意力、语言评分均低于对照组,差异有统计学意义(P<0.05);②CSVD组两侧丘脑NAA/Cr比值较对照组降低(左侧1.57±0.18、1.68±0.17、t=2.46、P=0.02;右侧1.66±0.21、1.78±0.19、t=2.23、P=0.03),差异有统计学意义(P<0.05);组间两侧丘脑Cho/Cr比值无明显差异(P>0.05);③CSVD组内,两侧丘脑NAA/Cr比值与MoCA总评分(左r=0.83,右r=0.79, P<0.05)、视空间与执行能力(左r=0.65,右r=0.46,P<0.05)、记忆(左r=0.59,右r=0.50, P<0.05)、注意力(左r=0.42,右r=0.52,P<0.05)、语言(左r=0.52,右r=0.41,P<0.05)、抽象(左r=0.47,右r=0.40,P<0.05)、定向力(左r=0.48,右r=0.42,P<0.05)评分均呈正相关(P<0.05),Cho/Cr比值与MoCA总评分及各子项评分无明显相关性(P>0.05).结论 CSVD患者丘脑存在神经元损伤或功能降低,这种代谢异常可能与患者广泛的认知损害相关.     

舌下神经鞘瘤一例

患者 男,32岁。左侧头部持续性胀痛1年,左侧舌肌萎缩、纤颤、伸舌左偏2个月,无其他不适。 CT检查示:左侧舌下神经管较对侧扩大,以外口明显,管周皮质变薄,稀疏,管内见等密度软组织影充填,管口周边未见异常密度影(图1)。MRI示:T_1WI上左舌下神经管内呈等信号,T_2WI呈明显高信号,病灶约0.6cm×0.7cm×2.0cm     

CT血管成像对COPD支气管动脉变化与肺功能关系的研究

目的 利用CT血管成像技术(CTA)研究慢性阻塞性肺疾病(COPD)患者支气管动脉的显示及支气管动脉管径与肺功能(PFT)指标间的关系,探索COPD支气管动脉变化与气道重塑的关系.方法 回顾性分析43例COPD患者的支气管动脉CTA图像,利用多平面重组(MPR)、最大密度投影(MIP)及容积再现(VR)对患者支气管动脉重建,统计支气管动脉支数,评价支气管动脉的显示情况,测量肺门水平各支支气管动脉管径,并分析支气管动脉管径与肺功能指标(FEV1,FEV1％,FVC,FEV1/FVC)的关系.结果 共显示支气管动脉102支.左支气管动脉41支(40.2％),平均管径1.51 mm.右支气管动脉61支(59.8％),平均管径1.98 mm.右支气管动脉管径较左侧粗,具有统计学意义(P=0.001).右支气管动脉管径与肺功能指标FEV1(r=-0.468,P＜0.001)、FEV1％(r=-0.476,P＜0.001)、FVC(r=-0.381,P=0.002)、FEV1/FVC(r=-0.468,P＜ 0.001)均呈负相关.左支气管动脉管径与FEV1(r=-0.314,P=0.046)、FEV1％(r=-0.357,P=0.022)呈负相关,与FVC(r=-0.265,P=0.094)及FEV1/FVC(r=-0.284,P=0.072)无显著相关性.结论 CTA可清晰显示COPD患者支气管动脉.右支气管动脉管径较左侧粗.右支气管动脉管径均与肺功能指标呈负相关.左支气管动脉管径与FEV1、FEV1％预呈负相关,说明支气管动脉与COPD的气道结构重塑关系密切.     

100名正常成人右中叶嵴、左舌叶嵴的CT表现

目的 提高对右中叶嵴、左舌叶嵴CT表现的认识.资科与方法复习100名正常成人胸部CT扫描片,观察右中叶嵴、左舌叶嵴的形态、大小、边缘和位置.为了探讨其诊断意义,分析30例原发性肺结核患者的CT资料.结果 两侧叶嵴形态分别为三角形、喇叭形、菱形、类圆形和不规则形.正常右中叶嵴的前后径平均为(17.8±2.2)mm,左右径平均为(17.3±2.1)mm,嵴角平均为(73.8±7.8)°;正常左舌叶嵴的前后径平均为(18.2±2.2)mm,左右径平均为(17.6±2.1)mm,嵴角平均为(66.0±9.6)°.叶嵴的外缘均显示凹入或平直.右中叶嵴位置较左舌叶嵴稍靠前靠下.在30例原发性肺结核CT片上,右中叶嵴增大主要是右肺门叶间下组及右下叶外侧组淋巴屯结增大;左舌叶嵴增大主要是左肺门叶间下组及左下叶外侧组淋巴结增大.30例中,19例(63.3%)伴有纵隔淋巴结增大,以右气管旁组(14例),右气管支气管组(12例)和隆突下组(17例)多见.增强扫描片上,淋巴结呈环状强化14例(46.6%),不均匀强化11例(36.7%),均匀强化5例(16.7%).结论 熟悉右中叶嵴、左舌叶嵴正常和异常的CT表现,有助于对肺门淋巴腺病的诊断与鉴别诊断.     

多层螺旋CT曲面重组对正常成人腭鞘管特征的研究

目的 采用MSCT高分辨扫描多方位显示腭鞘管并进行测量分析.方法 采用MS CT高分辨扫描和MPR及CPR技术对167例(男83例,女84例)翼腭窝结构正常受试者行高分辨率CT(HRCT)多方位薄层扫描,显示腭鞘管及其通连结构的正常形态,并在横断、冠状及斜矢状面上观察腭鞘管的走行和形态,测量其长度、前口、中口和后口径值.对所获数据进行单因素方差分析或两独立样本均数t检验.结果HRCT及其CPR图像对167例腭鞘管的显示率为98,8%(330/334),左侧腭鞘管平均长度为(1.18±0.22)cm,的、中、后口径分别为(0.19±0.06)、(0.10±0.04)和(0.16±0.07)cm,前口大于后口,中口最小(F=211.109,P<0.01).右侧腭鞘管平均长度为(1.07±0.29)cm,前、中、后口径分别为(0.19±0.06)、(0.10±0.03)和(0.16±0.06)cm,前口大于后口,中口最小(F=139.350,P<0.01).腭鞘管长度在男性[左:(1.18±0.22)cm;右:(1.12±0.31)cm]和女性[左:(1.07±0.25)cm;右:(1.02±0.25)cm]之间差异无统计学意义(左侧:t=0.919,右侧:t=1.117;P值均>0.05).不同性别左侧腭鞘管的几径[前、中、后口径:男性分别为(0.19±0.06)、(0.10±0.04)、(0.16±0.07)cm;女件分别为(0.20±0.08)、(0.10±0.04)、(0.15±0.05)cm]和右侧腭鞘管的口径[前、中、后口径:男性分别为(0.19±0.06)、(0.10±0.04)、(0.16±0.06)cm;女性分别为(0.20±0.06)、(0.09±0.04)、(0.15±0.05)cm]比较差异无统计学意义(t值:左侧分别为-1.183、0.190、1.660,有侧分别为-1.420、1.210、0.802;P值均>0.05).结论HRCT薄层扫描及CPR重组可清晰显示腭鞘管及其通连结构,有利于其解剖形态的观察和径线的测量.     

感音神经性耳聋患儿和正常儿童内耳解剖径线MRI测量对比研究

目的比较感音神经性耳聋患儿和正常儿童内耳解剖结构径线,并建立正常儿童内耳解剖结构径线正常值。资料与方法 47例极重度双侧感音神经性耳聋患儿(研究组)及19例正常儿童(对照组)分别采用MRI测量内耳解剖结构各重要径线,包括前半、后、外半规管高度及管径、耳蜗高度、耳蜗底周直径及管径,并进行比较,观察各径线与年龄、性别的相关性。结果研究组前半规管和后半规管高度、后半规管和外半规管管径均小于对照组(P<0.05),其余径线组间差异均无统计学意义(P>0.05)。对照组前半规管高度(5.25±0.50)mm、管径(0.91±0.13)mm,后半规管高度(5.16±0.73)mm、管径(1.09±0.22)mm,外半规管高度(3.38±0.55)mm、管径(0.93±0.21)mm,耳蜗高度(3.77±0.35)mm,耳蜗底周直径(6.88±0.52)mm、管径(2.15±0.26)mm。各径线与年龄无明显相关;研究组前、后半规管高度及耳蜗底周管径性别间差异有统计学意义(P<0.05),对照组前、后、外半规管高度及外半规管管径性别间差异有统计学意义(P<0.05),其余性别间差异无统计学意义(P>0.05)。结论感音神经性耳聋患儿与正常儿童前、后半规管高度及后、外半规管管径存在差异,MRI作为一种无创性检查,具有较高的软组织分辨率,对感音神经性耳聋患儿的诊断极为重要。     

肠系膜上动脉的MSCT成像研究及临床意义

目的:运用MSCTA研究活体肠系膜上动脉(superior mesenteric artery,SMA)的正常解剖。方法:收集行腹部CT增强扫描的患者中SMA正常者140例。采用MPR、VR、MIP,观察分析SMA空间解剖结构,包括其走行、分布;测量SMA与腹主动脉(abdominal aorta,AA)夹角,左肾静脉(left renal vein,LRV)与十二指肠水平部平面的SMA与AA间距,LRV穿越SMA与AA之间的管径及LRV在左肾门的最大管径。结果:SMA起始段走行呈转折型(A型)80例,径直型(B型)60例;SMA与AA夹角为56.6°±24.1°;LRV水平SMA与AA的距离为(13.51±6.48)mm;十二指肠水平部平面SMA与AA间距为(13.09±6.17)mm;LRV穿越SMA与AA之间的管径为(5.60±1.91)mm;LRV在左侧肾门最大管径为(9.97±1.47)mm;SMA与AA之间的夹角、间距均与SMA走行有关(P<0.05),与性别年龄无关(P>0.05);LRV穿越SMA与AA之间的管径,与SMA、AA之间的夹角有关(P<0.05),而LRV在左肾门的最大管径与SMA走行无关(P>0.05)。SMA分支较多,平均12支,大部分在11¹5支之间。结论:MSCTA是一种分辨力高、准确、快速、无创性的血管成像方法,多种后处理成像能清晰显示活体SMA的正常解剖结构。     

永存动脉干Ⅳ型的CT血管造影分析

目的 探讨永存动脉干Ⅳ型的CT血管造影特征.方法 回顾性分析CT血管造影证实的永存动脉干Ⅳ型共14例,男5例,女9例;评估心脏形态、室间隔缺损、动脉干骑跨、支气管动脉异常及侧支循环、其他心血管畸形特征.结果 CT血管造影显示:①双心室增大明显,伴右心房增大;②高位室间隔缺损,缺损平均直径(20.1±5.2) mm,其中男性为(23.7±5.2) mm,女性为(18.2±5.6) mm,差异无统计学意义(t=1.813,P=0.095,P＞0.05);③动脉干骑跨率为(50±5.2)%,男性为(51±2.3)%,女性为(49±6.3)%,差异无统计学意义(t=0.522,P=0.611,P＞0.05);动脉干平均内径(34.2±6.4) mm,男性为(39.1±4.3) mm,女性为(31.4±5.8) mm,差异有统计学意义( t=2.589,P=0.024,P＜0.05);④无肺动脉主干,心腰明显凹陷,肺血由支气管动脉及侧支循环供应,部分支气管动脉呈"残根"征;⑤男女各2例伴右位主动脉弓,其中1例男性有左侧肺静脉异常粗大,女性1例伴永存左上腔静脉.结论 永存动脉干Ⅳ型特征复杂多变,CT血管造影有利于提高诊断准确率,对手术有重要参考价值.     

320排冠脉CTA对动脉间型右冠状动脉起自左冠窦的评价

目的探讨320排冠脉CTA评价动脉间型右冠状动脉起自左冠窦的价值。方法 320排冠脉CTA检查中发现右冠状动脉起自左冠窦且右冠状动脉近段走行于升主动脉与肺动脉之间(动脉间型)8例患者纳入本组,同时分析8例右冠状动脉起始正常的冠脉CTA资料作为对照组。运用MPR、MIP以及VR等技术显示右冠状动脉的起源、开口和走行。利用测量工具评价收缩期和舒张期右冠状动脉近段管径的变化以及升主动脉右前壁与右冠状动脉近段之间的夹角,计算收缩期狭窄率。采用独立样本t检验比较2组间患者年龄、射线剂量、右冠状动脉近段管径在收缩期和舒张期的变化以及升主动脉与右冠状动脉之间夹角的差异。结果 8例动脉间型右冠状动脉起自左冠窦通过VR和薄层MIP重组均可以确诊,VR重组显示该变异最为直观。两组患者年龄和射线剂量差异无统计学意义。患者组右冠状动脉近段收缩期管径为(2.1±0.3)mm,舒张期为(2.6±0.7)mm,升主动脉与右冠状动脉之间夹角为(18.4°±1.4°),较对照组[收缩期(4.7±0.7)mm,舒张期(4.9±0.6)mm,夹角(60.7°±9.4°)]均明显缩小,差异有统计学意义(P0.05)。结论320排冠脉CTA能清楚显示右冠状动脉的异常起源和走行,动态评价近段血管在心动周期内的变化,为查明心肌缺血原因提供线索。     

Physiologic and pathologic calcifications and ossifications in the face and neck

The aim was to give a systematic presentation of physiologic and pathologic calcifications and ossifications in the face and neck with a special emphasis on clinical relevance. In a sometimes subacute setting one should recognize specific calcifications which often lead to important diagnoses such as fungal sinusitis or sclerosing labyrinthitis. In a more chronic situation intraocular calcifications in small children are pathognomonic for retinoblastoma. Juxtatumoral sclerosis of the laryngeal cartilage in laryngopharyngeal carcinoma is usually caused by tumor infiltration of the cartilage resulting in a higher tumor stage and, this way, has a major impact on the therapeutical strategy. Calcified lymph nodes are mainly unspecific but can be the result of tuberculosis or metastases of thyroid cancer. Cross-sectional imaging methods, most of all computed tomography, are ideally suited to reveal head and neck calcifications and ossifications, especially those which are clinically relevant.     

Head and neck infection and inflammation

This article discusses the imaging manifestations of infectious and inflammatory conditions of the head and neck. Special attention is paid to the sites, routes of spread, and complications of neck infections. Because the clinical signs and symptoms and the complications of these conditions are often determined by the precise anatomic site involved, anatomic considerations are stressed. Familiarity with the fascial layers, spaces of the neck, and the contents of each space is helpful for this discussion. The fascial layers of the neck are important barriers to infection, and once infection is established, the fascial layers play a part in directing its spread.     

Oxygen uptake and ventilation during rowing and running in females and males

This study evaluated if the ventilatory response to exercise is impaired by the cramp position of rowing. Maximal oxygen uptake (VO2max), maximal expiratory volume (VEmax), and maximal heart rate (HRmax) during rowing and running were compared in 55 males (age, mean +/- SD, 21 +/- 3 years; height 176 +/- 5 cm; body mass 72 +/- 6 kg) and 18 females (age 20 +/- 2 years; height 164 +/- 5 cm; body mass 61 +/- 4 kg). VEmax was larger during rowing than during running (males, 157 +/- 16 vs. 147 +/- 13 L min(-1); 114 +/- 9 vs. 105 +/- 11 L min(-1), P<0.01). Also VO2max was larger during rowing than during running (males, 4.5 +/- 0.5 vs. 4.3 +/- 0.4 L min(-1); females, 3.3 +/- 0.4 vs. 3.2 +/- 0.4 L min(-1), P<0.01). However, HRmax was lower during rowing than during running (males, 194 +/- 8 vs. 198 +/- 11 beats min(-1); females, 192 +/- 6 vs. 196 +/- 8 beats min(-1), P<0.05). VEmax was correlated to body mass and fat-free mass, as was VO2max. Thus, the oxygen pulse (VO2max/HRmax) was larger during rowing than during running, while the ventilatory equivalent for oxygen (VEmax/VO2max) was similar. We showed that bending the body during rowing does not seem to impair ventilation either in males or in females. The results indicate that VEmax and VO2max relate to body size and fat-free mass for both females and males. The findings indicate that the involvement of more muscles, the entrainment, and the body position during rowing facilitates ventilation and venous return and lowers maximal heart rate.     

幽门螺杆菌分泌与重组表达的VacA蛋白的分离纯化及其致细胞空泡效应与凋亡的对比研究

目的：分离纯化幽门螺杆菌分泌和重组表达的细胞空泡毒素抗原（ VacA）蛋白,并评价其致细胞空泡效应及致细胞凋亡效应。方法分别从幽门螺杆菌ATCC26695菌株培养上清和重组表达VacA蛋白的pQE30-VacA-E．coliM15基因工程菌中分离纯化VacA蛋白,经酸化后,以不同终浓度（5,10 ng／ml）分别与人胃腺癌AGS细胞共孵24 h,观察致空泡效应,并通过流式细胞术检测细胞凋亡。结果成功分离纯化出幽门螺杆菌分泌和重组表达的VacA蛋白;幽门螺杆菌分泌的VacA蛋白能显著引起AGS细胞的空泡样改变及凋亡（P＜0．01）,而重组表达的VacA蛋白致细胞空泡样改变及凋亡不显著（ P＞0．05）。结论幽门螺杆菌分泌的VacA蛋白有良好的空泡毒性及致凋亡效应,而重组表达的VacA蛋白无致空泡及凋亡效应,幽门螺杆菌分泌的VacA蛋白可用于VacA作用机制的研究。     

化学和生物学融合对国际武器公约履约的影响

化学武器公约（ CWC）和生物武器公约（ BWC）是为禁止生产、发展、储存和使用化学武器和生物武器而制定的国际公约。近年来,科学技术快速发展,知识交叉渗透,学科之间出现整合和融合,促进了科技进步和经济发展。其中化学和生物学融合在有力促进制药、健康卫生、绿色化学和环境保护等产业进步的同时,也对化学和生物武器公约的履约产生了重要的影响。该文综述了与化学武器和生物武器公约相关的化学和生物学融合进展,并分析其对公约履约的影响。     

Old and dangerous: Prison and dementia

Older prisoners are the fastest growing group of prisoners in many countries. The purpose of this study is to explore the phenomenon of detention of persons suffering from dementia. Medline searches were conducted for relevant articles, chapters and books published until August 2016. Search terms included dementia, elderly, prison and criminal. Publications found through this indexed search were reviewed for further relevant references. As results, there is a lack of data about elderly with dementia in prisons. Given the rise in the average age, it is reasonable to hypothesize that the number of older prisoners is growing. Moreover, some elderly are imprisoned with a concomitant cognitive impairment or psychiatric disorder while others will develop such diseases once incarcerated. At the present time, legal and social systems seem unprepared to handle the phenomenon of dementia in prison. As proposal, health assessments for older first time offenders should become a practice inside the correctional facilities and include an evaluation for specific health issues, such as psychiatric comorbidity and cognitive impairment.     

Kidney and iodinated and gadolinium-based contrast agents

In patients with renal failure, iodinated contrast agents may cause acute deterioration of the renal function and gadolinium-based contrast agents (GBCAs) may cause nephrogenic systemic fibrosis (NSF). The administration of a contrast agent must thus be reviewed for each patient and evaluation of renal function is paramount even though its estimation using formulas derived from the creatinine level may fluctuate. For iodinated contrast agents, contrast induced nephropathy is reduced by hydratation, preferably intravenous, when the GFR is less than 60 ml/min. The risk for intravenous injections is less than the risk for arterial injections, and the GFR threshold may be reduced to 45 ml/min. For gadolinium-based contrast agents, patients at risk for NSF are those with end-stage renal disease and patients undergoing dialysis. In such cases, the injection of a gadolinium-based contrast agent is only considered after a risk-benefit analysis has been completed, an alternate linear or macrocyclic agent issued and the dose limited to 0,1 mmol Gd/kg. Recently, recommendations from US and European agencies have converged. Learning objectives: to be familiar with the risk factors of CIN with iodinated contrast agents; to be familiar with hydration procedures for patients at risk of CIN; to be familiar with the diagnostic criteria of NSF; to be familiar with the classification of GBCA with regards to the risk of NSF; to be familiar with the contraindications of the different groups of GBCA.     

Coracoclavicular and coracoacromial ligament calcification and ossification

Thirty-six patients with calcification or ossification at or around the coracoclavicular and coracoacromial regions were analyzed with regard to type, location, and configuration of the deposits and related clinical history. Calcification or ossification in the coracoclavicular region resulted largely from trauma (36%) or renal failure (28%). Trauma patients may develop punctate calcification or ossification but do not develop the tumoral type of calcification. About 5% of the renal failure patients had coracoclavicular ligament calcifications, one-half of which were of the tumoral type. Renal failure patients may have punctate or tumoral calcifications but do not develop ossification.     

Cross-sectional and longitudinal comparisons of self-reported and device-assessed physical activity and sedentary behaviour

ObjectivesTo examine the longitudinal associations and differences between self-reported and device-assessed physical activity (PA) and sedentary behaviour (SB), using a multifaceted statistical approach.DesignLongitudinal measurement burst.MethodsIn total, 52 university students (78% female) aged 18–38 years (mean = 21.94 ± 4.57 years) participated. The study consisted of three blocks of six days of measurement, during which participants wore an accelerometer on their wrist for the entire block, and self-reported their PA over the 6 days at the end of each block.ResultsMeaningful latent differences between methods were observed for moderate PA and SB across all three assessment periods, such that participants underreported the time spent in each activity. Bland–Altman plots revealed a positive mean difference for vigorous PA, with over-reporting increasing as mean levels increased. Negative mean differences were observed for all other intensities. Underreporting of moderate PA increased as the mean level increased, whereas for light PA and SB, underreporting decreased at high levels. Repeated measures correlations revealed a meaningful association for vigorous PA only, suggesting that as self-reported minutes increase so too do device-measured minutes.ConclusionsWe found evidence of cross-sectional and longitudinal differences and weak associations between self-reported and device-assessed PA and SB. Future work is needed to enhance the quality of self-reported methods to assess PA and SB (e.g., face and content validity), and consider improvements to the processing of device-based data.