血流多普勒与组织多普勒Tei指数评价早产儿及足月儿的右心室功能分析

目的应用组织多普勒成像技术(TDI)评价早产儿及足月儿右心室Tei指数的改变,并与传统血流多普勒的测量方法比较,为临床评估右心室功能及治疗提供依据。方法对100名新生儿中早产儿和足月儿各50名进行两种多普勒超声心动图技术测定右心室等容收缩期(ICT)与等容舒张期时间(IRT)之和(ICT+IRT)及射血时间(ET),并计算Tei指数。结果血流多普勒与组织多普勒两种方法测得的早产儿右心室Tei指数均高于足月儿,差异有统计学意义(P<0.01);且所有受检新生儿的组织多普勒图像较传统血流多普勒图像清晰易辨认,两种方法测量结果差异无统计学意义(P>0.05)。结论早产儿右心室功能低于足月儿,组织多普勒可取代传统方法测量Tei指数,是评估新生儿特别是早产儿右心功能的一种简便而敏感的方法。     

组织多普勒Tei指数评价肺动脉高压患者右心室功能

目的：探讨组织多普勒（TDI）与脉冲多普勒（PW）Tei指数评价肺动脉高压（PAH）患者右心室功能的价值.材料和方法：PAH患者68例,根据肺动脉收缩压（PASP）分为轻、中、重度3组,健康体检者23例为对照组,于心尖四腔切面应用TDI获取各组右室游离壁三尖瓣环位点的频谱图,测量等容舒张期（IRT）、等容收缩期（ICT）、射血期（ET）及Tei指数（TDI-Tei）;并应用PW测量IRT、ICT、ET及Tei指数（PW-Tei）.结果：①TDI-Tei对照组、轻、中、重度PAH组依次增高（P〈0.05）;PW-Tei轻、中、重度PAH组均高于对照组（P〈0.05）,重度组高于轻、中度组（P〈0.05）,轻、中度组间差别无统计学意义（P〉0.05）.②两种多普勒测值,TDI-Tei明显高于PW-Tei（P〈0.05）;TDI-Tei与PW-Tei呈正相关（r=0.706,P〈0.01）.结论：①PAH患者右心室整体功能受损;②TDI-Tei可以敏感、准确地反映右心室功能,优于且高于PW-Tei,二者呈正相关.     

全方位M型超声Tei指数测量对早期酒精性心肌损害左室功能的评价

目的:采用全方位M型(free angle motion mode,FAM)超声测量左心室Tei指数及等容收缩指数(心室等容收缩时间/射血时间,ICT/ET)、等容舒张指数(心室等容舒张时间/射血时间,IRT/ET)等相关参数,评价早期酒精性心肌损害左室功能的变化。方法:收集45例不饮酒健康男性作为A组(正常对照组);另收集91例饮酒者分为3组:B组36例,每日饮白酒80~150g或啤酒1 000~1 500mL,每周3~5d,饮酒史10年;C组30例,饮酒史10年,其他条件同B组;D组25例,每日饮白酒≥150g或啤酒≥2 000mL,每周3~5d,饮酒史10年,饮酒量符合酒精性心肌病诊断标准。对4组行常规超声检查,测定左室舒张末期内径(LVDd)、左室收缩末期内径(LVDs)、舒张末期室间隔厚度(IVSTd)、舒张末期左室后壁厚度(LVPWTd)、左室射血分数(LVEF)、舒张早期血流峰值速度(E)与舒张晚期血流峰值速度(A)比值(E/A)及FAM参数,获得左室Tei指数及ICT/ET、IRT/ET等相关参数。结果:各常规超声参数A组与B组间差异无统计学意义(P均0.05);C组LVDd、LVDs、IVSTd、LVPWTd、LVEF与A、B组比较差异均无统计学意义(P均0.05);C组E/A与A、B组比较差异均有统计学意义(P均0.01);D组各常规超声参数与A、B、C组比较差异均有统计学意义(P均0.01)。Tei指数在A组及B、C组间差异有统计学意义(P均0.05),在D组与A、B组间差异有统计学意义(P均0.01),在D组与C组间差异有统计学意义(P0.05)。除A、B组间ICT/ET差异无统计学意义外(P0.05),C、D组ICT/ET、IRT/ET值均大于A、B组(P均0.05),同时D组ICT/ET、IRT/ET值亦大于C组(P均0.05)。结论:应用FAM技术测量左室Tei指数并结合ICT/ET、IRT/ET等相关参数可作为全面评价早期酒精性心肌损害左室功能变化的手段之一。     

Tei指数在评价海员慢性阻塞性肺病患者右心室功能中的应用

目的 探讨Tei指数在评价海员慢性阻塞性肺病患者右心室功能中的作用.方法 在我院2006年至2007年住院的海员患者及健康体检者中选取慢性阻塞性肺病患者38例,正常对照组98例.行超声心动图检查测量右心Tei指数、肺动脉收缩压等.结果 (1)与正常对照组相比,慢性阻塞性肺病患者右心室等容舒张时间(IRT)及等容收缩时间(ICT)明显延长,射血时间(ET)明显缩短,右室Tei指数明显升高(P<0.01);(2)肺动脉高压组间比较显示肺动脉高压的程度对右室Tei指数有一定影响,组间比较差异有统计学意义(P<0.01).(3)右心大小组间比较显示右室扩大的Tei指数增大,但组间比较差异无统计学意义(P>0.05).结论 (1)Tei指数是评价慢阻肺患者右心室收缩舒张功能简便、敏感、综合的多普勒超声新指标;(2)右心室Tei指数受压力负荷增加影响大,受容量负荷增加影响小,其右室功能受损程度与肺动脉收缩压升高有一定相关性.     

定量组织多普勒Tei指数评价重度妊高征胎儿心功能的研究

目的:应用定量组织速度成像技术(quantitative tissue velocity imaging,QTVI)所测Tei指数评价重度妊高征患者胎儿心功能的临床价值.方法:应用qrvi测量30例重度妊高征患者和60例正常孕妇胎儿右室房室瓣环室壁运动的射血期(ET)、等容收缩期(ICT)和等容舒张期(IRT)的时间问期,计算胎儿Tei指数.结果:重度妊高征组的IRT ICT和Tei指数显著高于与对照组.结论:重度妊高征不仅对母体脏器造成危害,而且累及胎儿心脏功能.     

彩色多普勒超声对高血压左心室向心性与离心性心肌肥厚患者左心室舒张功能的评价

目的:探讨应用多普勒超声评估高血压左心室向心性与离心性肥厚患者左心室舒张功能障碍的差异,为评价左心室舒张功能受损程度提供依据。方法:选择原发性高血压患者246例,根据左心室构型分为正常构型组、向心性重构组、离心性肥厚组、向心性肥厚组。左心室舒张功能的评估应用脉冲多普勒测量二尖瓣舒张早期血流峰值(E)及舒张晚期血流峰值(A),计算E/A值;组织多普勒测量二尖瓣环舒张早期运动峰值速度(Em),计算E/Em值。结果:与正常构型组相比,室间隔厚度及左心室厚壁厚度在向心性重构组、离心性肥厚组及向心性肥厚组均显著增加(均P0.01)。与正常构型组相比,左心室舒张末期内径在向心性重构组明显减小,在离心性肥厚组明显增大(均P0.01)。左心房内径在离心性肥厚组和向心性肥厚组比正常构型组和向心性重构组显著增加(P0.01),在离心性肥厚组和向心性肥厚组之间比较差异无统计学意义(P0.05),向心性重构组比正常构型组减小(P0.05)。与正常构型组比较,反映左心室舒张功能的参数E/A和Em在离心性肥厚组和向心性肥厚组均显著降低(均P0.01);E/Em在向心性肥厚组比离心性肥厚组显著增高(P0.01)。结论:在高血压左心室肥厚患者中,向心性肥厚患者的左心室舒张功能障碍比离心性肥厚患者严重。     

定量组织速度成像技术及组织追踪成像技术评价妊娠期高血压疾病患者心功能

目的:采用定量组织速度成像技术(quantitative tissue velocity imaging,QTVI)及组织追踪成像技术(tissue tracking imaging,TTI)超声心动图评价妊娠期高血压疾病(hypertensive disorders complicating pregnancy,HDCP)患者心功能。方法:测量30例HDCP患者(HDCP组)和50例健康孕妇(对照组),在心尖四腔心切面,用QTVI及TTI测量左右心室心肌运动的收缩期峰值速度、Tei指数、收缩期峰值位移。结果:HDCP组与对照组的EF值分别为(61.00±2.35)%、(62.00±3.82)%,差异无统计学意义。HDCP组与对照组左心室心肌运动的收缩期峰值速度分别为(7.37±1.82)cm/s、(8.13±1.64)cm/s,右心室收缩期心肌运动峰值速度分别为(6.90±0.52)cm/s、(7.80±0.38)cm/s,左心室收缩期峰值位移分别为(10.43±1.35)mm、(11.95±1.95)mm,右心室收缩期峰值位移分别为(7.20+1.18)mm、(8.60±1.89)mm,左心室Tei指数分别为0.59±0.06、0.46±0.07,右心室Tei指数分别为0.62±0.09、0.47±0.08,2组间比较,差异均有统计学意义(P0.05)。结论:QTVI及TTI超声心动图可定量评价HDCP患者心功能改变。     

Tei指数评价川崎病患儿心脏功能的临床意义

目的：应用Tei指数评价川崎病（ kawasaki disease ,KD）患儿心脏功能,探讨其临床意义。方法超声心动图测量KD急性期和恢复期患儿62例的左室射血分数（ EF）、左室短轴缩短率（ FS）、二尖瓣口舒张期血流E/A比值、肺静脉血流S/D比值、左右心室等容收缩期（ICT）、等容舒张期（IRT）、射血时间（ET）和计算左、右心室Tei指数,并与80例年龄、性别匹配的健康儿童作比较。结果 KD急性期左心室Tei指数较健康儿童明显增高（0．43±0．07 vs 0．37±0．06,P＜0．01）,恢复期组左心室Tei指数减低,接近健康儿童（0．40±0．09 vs 0．37±0．06）,差异无统计学意义;KD急性期右心室Tei指数增加,与健康对照组相比差异有统计学意义（0．31±0．06 vs 0．25±0．05,P＜0．01）,恢复期组右心室Tei指数减低,逐渐接近正常（0．30±0．08 vs 0．25±0．05）,差异无统计学意义。结论 KD急性期患儿存在心脏整体功能异常,Tei指数能准确、敏感地评价患儿心脏整体功能。     

Tei指数评价正常胎儿和心力衰竭胎儿心功能的应用价值

目的:探讨Tei指数在评价正常胎儿和心力衰竭胎儿心脏功能中的应用价值。方法:测量400例正常胎儿(20~25周、26~30周、31~35周、36~40周各100例)左、右心室Tei指数,分析孕周、心率对此指数的影响。测量8例心力衰竭胎儿和与其孕龄匹配的30例正常胎儿左、右心室Tei指数,分析两者之间有无显著性差异。结果:400例正常胎儿左心室Tei指数为0.319±0.0104,右心室Tei指数为0.328±0.105,两者之间具有相关性(r=0.766,P<0.001);不同孕龄胎儿之间的Tei指数差异均无显著性意义(P>0.05)。胎儿左、右心室Tei指数与心率无明显相关(P>0.05)。8例心力衰竭胎儿左室Tei指数为0.556±0.141,右室Tei指数为0.819±0.280,比正常胎儿左、右心室Tei指数显著升高,差异有显著性意义(P<0.01)。结论:Tei指数是一种简单可靠的定量综合评价心脏收缩和舒张功能的指标。     

多普勒Tei指数评价高血压右室功能

目的:探讨多普勒Tei指数评价高血压患者右室功能的价值。材料和方法:受试者分为高血压左室肥厚组(A组)、无左室肥厚组(B组)和正常对照组(C组),每组30例。应用多普勒超声测量三尖瓣及肺动脉瓣血流频谱,计算右室Tei指数,二尖瓣口舒张晚期A峰和早期血流E峰峰值之比(A/E)及左室射血分数(EF)。结果:三组间的EF无差异(P>0.05)。A/E比值分别为1.484±0.221、1.269±0.143、0.893±0.289,呈A组>B组>C组(P<0.01);Tei指数分别为0.596±0.158、0.486±0.104、0.280±0.066,呈A组>B组>C组(P<0.01)。结论:多普勒Tei指数可以综合评价高血压患者的右室功能,但不能单独评价收缩功能或舒张功能。     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.