1H-MRS评价颞叶癫痫患者杏仁核代谢物比值

目的 采用¹H-MRS探讨颞叶癫痫(TLE)患者双侧杏仁核的各代谢物比值改变.方法 对15例TLE患者(TLE组)和15名健康志愿者(正常对照组)行杏仁核¹H-MRS扫描,比较两组杏仁核的N-乙酰天门冬氨酸(NAA)/、NAA/Cr、NAA/Cho和Cho/Cr比值,分析TLE患者双侧杏仁核各代谢物比值与癫痫病程和发病年龄的相关性.结果 TLE组患侧杏仁核NAA/(Cho+Cr)和NAA/Cr比值与正常对照组比较均明显减低(P均 <0.05);TLE组患侧杏仁核NAA/(Cho+Cr)、NAA/Cr、NAA/Cho和Cho/Cr比值与TLE组对侧比较差异均无统计学意义(P均 >0.05);TLE组对侧杏仁核NAA/(Cho+Cr)、NAA/Cr和NAA/Cho比值与正常对照组比较均明显减低(P均 <0.05).TLE组双侧杏仁核NAA/(Cho+Cr)、NAA/Cr和NAA/Cho比值与癫痫病程及发病年龄均无相关性(P均 >0.05).结论 TLE患者双侧杏仁核存在显著的代谢异常,双侧杏仁核可能作为传导通路的一个环节,参与TLE的发病过程.     

创伤性脑损伤后认知障碍的海马氢质子磁共振波谱分析

目的:探讨海马氢质子磁共振波谱(1H-MRS)在创伤性脑损伤(TBI)后认知障碍的辅助诊断和评估中的价值。方法:选取轻度TBI后认知障碍患者(mi-TBI组)9例、中度TBI后认知障碍患者(mo-TBI组)19例,同时招募健康对照组10例,进行1H-MRS检查后分析三组双侧海马N-乙酰天门冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)代谢物浓度。采用简易精神状态量表(MMSE)和蒙特利尔认知功能评估量表(MoCA)进行认知评估,比较三组间认知功能评分和代谢物比值的差别,并进行相关性分析。结果:mi-TBI组、mo-TBI组的双侧海马NAA/Cr值、NAA/(Cho+Cr)值均低于健康对照组(P0.05),右侧海马Cho/Cr值均高于健康对照组(P0.05),左侧海马Cho/Cr值差异无统计学意义(P0.05)。mi-TBI组、mo-TBI组的MMSE、MoCA评分均低于健康对照组(P0.05)。mi-TBI组的MMSE、MoCA评分与双侧海马NAA/Cr均呈正相关(P0.05),与左侧海马Cho/Cr无显著相关性(P0.05),与右侧海马Cho/Cr呈负相关(P0.05),与双侧海马NAA/(Cho+Cr)均呈正相关(P0.05)。mo-TBI组MMSE、MoCA评分均与左侧海马NAA/Cr呈正相关(P0.05),与右侧海马NAA/Cr呈负相关(P0.05),与双侧海马Cho/Cr无显著相关性(P0.05),但与健康对照组相比,Cho/Cr比值有升高的趋势,与双侧海马NAA/(Cho+Cr)均呈正相关(P0.05)。结论:~1H-MRS结合神经认知测试有助于更客观、更准确地辅助诊断TBI后认知功能障碍。     

正常中年人海马MR波谱相关参数分析

目的应用氢质子磁共振波谱(1H-MRS)技术,分析正常中年人双侧海马在不同年龄组、不同部位各代谢物比值变化规律,为临床早期诊断及治疗海马相关性疾病提供参考依据。材料与方法从社区健康志愿者中选取符合标准者276名,按年龄分3组,A组:壮实期(41~48岁)90名,B组:稳健期(49~55岁)93名,C组:调整期(56~65岁)93名,行常规颅脑MR平扫、双侧海马MRS扫描,计算双侧海马头、体、尾部NAA/Cr、Cho/Cr、NAA/(Cho+Cr)值,分析不同性别间、左右侧别间、各年龄组间及同年龄组不同部位间各参数的差异及各参数与年龄的相关性。结果 NAA/Cr、Cho/Cr、NAA/(Cho+Cr)值在男女之间、左右侧别间差异无统计学意义(P0.05);各年龄组间相同部位差异有统计学意义(P0.05),NAA/Cr、NAA/(Cho+Cr)值A、B组均高于C组(P0.05),Cho/Cr值A组低于C组(P0.05);NAA/Cr、Cho/Cr值在同年龄组不同部位间差异有统计学意义(P0.05),NAA/Cr值在A、B、C组海马头、体部均高于尾部(P0.05),Cho/Cr值A、B组海马体部均高于尾部。NAA/Cr、NAA/(Cho+Cr)值与年龄呈负相关(r值分别为-0.486、-0.653,P0.05);Cho/Cr值与年龄呈正相关(r值为0.482,P0.05)。结论 ~1H-MRS能反映正常中年人海马不同部位代谢物相对含量的变化,为早期临床诊断及治疗海马相关性疾病提供参考依据。     

男性精神分裂症患者前额叶和丘脑质子波谱分析

目的 探讨男性精神分裂症患者前额叶、丘脑的氢质子磁共振波谱(1H-MRS)的特点.方法 以26例7 d内未使用抗精神病药物及影响脑内乙酰胆碱神经递质药物的男性精神分裂症患者为研究组,以28名正常人为对照组.在入组24 h内两组采用多体素1H-MRS检测前额叶和丘脑生化代谢物N-乙酰基天门冬氨酸(NAA)、胆碱复合物(Cho)与肌酸复合物(Cr),完成NAA/Cr值、Cho/Cr值和NAA/(Cho+Cr)值的计算.结果 与对照组相比,研究组左侧前额叶及左、右侧丘脑NAA/Cr值(分别为1.40±0.34、1.45±0.31和1.51±0.32)均低于对照组(分别为1.69±0.31、1.69±0.23和1.70±0.28),差异有统计学意义(P均<0.05).Cho/Cr值和NAA/(Cho+Cr)值两组间比较差异无统计学意义.结论 男性精神分裂症患者的1H-MRS与正常人存在差异,左侧前额叶及丘脑同时存在神经元的功能和(或)结构异常.     

轻度阿尔茨海默病和血管性痴呆患者认知损害及与扣带回后部和海马氢质子磁共振波谱的相关性研究

目的分析轻度阿尔茨海默病(AD)和血管性痴呆(VD)患者的认知损害程度及与氢质子磁共振波谱(1H-MRS)的关系,探讨其对AD与VD的诊断和鉴别诊断的作用。方法 AD组28例、VD组30例、健康对照组22例,采用简易精神状态量表(MMSE)、蒙特利尔认知评估量表(Mo CA)进行认知功能评分;采用刺激回波序列进行检测,计算双侧海马和扣带回后部的N-乙酰天冬氨酸/肌酸(NAA/Cr)、肌醇/肌酸(MI/Cr)、胆碱/肌酸(Cho/Cr)、N-乙酰天冬氨酸/肌醇(NAA/MI)等的比值;比较各组间认知功能评分和各代谢物比值的差别,并进行相关分析。结果 (1)AD组和VD组的Mo CA总分、MMSE评分均低于对照组,差异有统计学意义(P<0.05);VD组汉密尔顿焦虑量表(HAMA)评分高于AD组和对照组(P<0.05);(2)AD组和VD组左侧海马、扣带回后部的NAA/Cr比值均低于对照组(P<0.05);AD组和VD组扣带回后部的Cho/Cr比值低于对照组;AD组和VD组左侧海马、扣带回后部的MI/Cr比值高于对照组(P<0.05);AD组和VD组左侧海马、扣带回后部的NAA/MI比值均低于对照组(P<0.05)。与VD组相比,AD组左侧海马、扣带回后部的NAA/Cr比值升高,差异有统计学意义(P<0.05),扣带回后部的Cho/Cr比值降低,差异有统计学意义(P<0.05),左侧海马、扣带回后部的MI/Cr比值升高,差异有统计学意义(P<0.05);(3)AD组和VD组的Mo CA总分、MMSE评分与左侧海马、扣带回后部的NAA/Cr存在正相关(P<0.05),AD组MMSE评分与扣带回后部的NAA/MI存在正相关(P<0.05),而VD组MMSE评分与扣带回后部的NAA/MI无相关性(P>0.05)。结论在认知损害程度方面轻度AD患者与VD患者具有相似性,且认知损害程度与左侧海马、扣带回后部的1H-MRS具有相关性,认知功能评分与1H-MRS结合可作为AD和VD早期诊断、鉴别诊断的重要工具。     

枕叶皮质MR频谱对脑震荡的应用价值

目的用绝对定量对脑震荡患者进行枕叶皮质质子MR频谱(1H-MRS)研究,探讨脑震荡后脑代谢物的变化。材料与方法对轻度脑外伤,符合脑震荡临床诊断的36例患者进行研究,10名正常志愿者作为对照组,行常规MRI平扫及1H-MRS检查。主要观察的代谢物指标为N-乙酰天冬氨酸(NAA)、胆碱(Cho)、肌酸(Cr)等,采用LCModel软件进行代谢物绝对浓度定量,获取NAA、Cr、Cho浓度,以及NAA/Cr、Cho/Cr比值。结果与对照组对比,脑震荡组NAA浓度、NAA/Cr降低,差异有统计学意义(P<0.05),Cho浓度和Cho/Cr比值略升高,无统计学意义。结论 1H-MRS能够反映脑震荡患者损伤后脑代谢物的变化。     

隐性肝性脑病患者的脑氢质子磁共振波谱成像研究

目的探讨隐性肝性脑病(CHE)患者脑内代谢物质变化的特点。方法采用磁共振氢质子波谱(1H-MRS)技术。选取17例CHE患者和17例健康志愿者,采用西门子Trio?Tim?3.0?T超导型磁共振扫描仪行后扣带回的单体素点分辨自旋回波波谱检查,计算N-乙酰天门冬氨酸(NAA)、肌酸(Cr)、胆碱(Cho)、肌醇(m I)、谷氨酰胺复合物(Glx)与肌酸(Cr)的比值,并应用SPSS?18.0统计软件分别比较两组间NAA/Cr、Cho/Cr、m I/Cr、Glx/Cr的比值差异有无统计学意义。最后对CHE组分别行各代谢物与神经心理学实验的相关性分析。结果 1与正常对照组相比,CHE组后扣带回m I/Cr、Cho/Cr减低,Glx/Cr升高,差异有统计学意义(P??0.05);2通过各代谢物比值与NCT-A及DST实验评分做相关分析发现,CHE患者后扣带回Cho/Cr、m I/Cr与NCT-A实验呈负相关。结论 1H-MRS技术可用于CHE的早期筛查和初步诊断,后扣带回MRS改变可提示CHE的存在。     

1H-MRS在脑胶质瘤肿瘤周围组织的临床应用研究

目的分析脑胶质瘤肿瘤周围组织的1H-MRS表现,探讨脑胶质瘤肿瘤周围组织的1H-MRS特点与肿瘤侵袭性的相关性。方法收集经临床手术、病理证实的脑胶质瘤36例,按照MRI检查结果分成两组:肿瘤周围区域有水肿组、肿瘤周围区域无水肿组。所有患者在术前行1H-MRS检查,均在MR非增强成像的基础上获得。使用1.5T超导磁共振、多体素扫描、点分辨表面线圈法,检测不同区域代谢物变化。结果脑胶质瘤肿瘤周围组织的1H-MRS表现:Cr轻度下降,NAA下降,Cho增高。肿瘤周围水肿组织和肿瘤组织、对侧正常脑组织的NAA/Cr、Cho/Cr、NAA/Cho比值存在显著性差异(P<0.05)。脑胶质瘤肿瘤周围无水肿组织和肿瘤组织的NAA/Cr、Cho/Cr、NAA/Cho比值存在显著性差异(P<0.05);肿瘤周围无水肿组织和对侧正常脑组织的NAA/Cr、NAA/Cho比值存在显著性差异(P<0.05),但Cho/Cr比值无显著性差异(P>0.05)。20例肿瘤周围水肿组与16例肿瘤周围无水肿组的肿瘤组织、肿瘤周围组织的NAA/Cho比值均存在显著性差异(P<0.05),但NAA/Cr、Cho/Cr比值无显著性差异(P>0.05)。结论1H-MRS可评价肿瘤周围组织(水肿区或无水肿区)肿瘤细胞浸润情况,反映肿瘤生长潜能,为制定治疗方案提供帮助。     

多体素1H-MRS在脑胶质瘤强化周围区域中的临床应用

目的：应用多体素氢质子磁共振波谱（1H-MRS）成像探讨脑胶质瘤强化周围区域1H-MRS代谢物改变特点,评价1H-MRS在确定胶质瘤浸润范围中的应用价值。方法：搜集经病理证实的脑胶质瘤24例,按WHO诊断标准分为低级别胶质瘤组（Ⅰ、Ⅱ级）和高级别胶质瘤组（Ⅲ、Ⅳ级）,按照MRI检查结果分为肿瘤强化周围区域有水肿组和肿瘤强化周围区域无水肿组。所有患者在术前行1H-MRS检查,检测不同区域代谢物的变化。结果：①低级别胶质瘤瘤周组织和对侧正常脑组织的Cho：Cr、NAA：Cho及NAA：Cr比值存在显著性差异（P〈0.05）;高级别胶质瘤瘤周组织和对侧正常脑组织的Cho/Cr、NAA/Cho比值存在显著性差异（P〈0.05）,但NAA/Cr值无显著性差异（P〉0.05）;低、高级别胶质瘤瘤周组织的各代谢物比值均无显著性差异（P〉0.05）;②肿瘤周围有水肿组瘤周组织和对侧正常脑组织的Cho/Cr、NAA/Cho及NAA/Cr比值存在显著性差异（P〈0.05）;肿瘤周围无水肿组瘤周组织和对侧正常脑组织的Cho/Cr、NAA/Cho比值存在显著性差异（P〈0.05）,但NAA/Cr值无显著性差异（P〉0.05）;肿瘤周围有水肿组和肿瘤周围无水肿组瘤周组织的各代谢物比值均无显著性差异（P〉0.05）。结论：多体素1H-MRS可评价肿瘤强化周围区域肿瘤细胞浸润范围,对确定胶质瘤的边界具有一定意义。     

MRI与1H-MRS在重症EV71脑炎中的应用价值

目的 观察重症肠道病毒71型(EV71)脑炎患儿MRI和氢质子磁共振波谱(1H-MRS)的改变,探讨1H-MRS临床应用价值.方法 选取10例重症EV71脑炎患儿进行头颅MRI和脑干1H-MRS检查,观察代谢物N-乙酰天门冬氨酸(NAA)、肌酸(Cr)和胆碱复合物(Cho)及NAA/Cr、Cho/Cr及NAA/(Cho+Cr)代谢物比值变化,并和10例健康儿童进行比较.结果 病例组MRI异常6例,1例病灶累及中脑、脑桥顶盖、延髓、双侧枕叶,1例累及脑桥顶盖、延髓,1例累及颈髓6～7和胸髓1～12,1例累及双侧额、颞叶,1例累及双侧额顶颞叶,1例累及颈髓1～4,病灶增强扫描未见强化,T1WI呈低信号,T2WI和T2/FLAIR高信号.1H-MRS异常10例,与对照组相比,Cho/Cr比值(2.15±0.41)增高(P>0.05),NAA/Cr比值(1.48±0.34)、NAA/(Cho+cr)比值(0.51±0.13)显著降低(P<0.01).结论 EV71脑炎急性期1H-MRS改变主要以神经元损伤为主;1H-MRS结合MRI,可为重症EV71脑炎的早期诊断和治疗提供全面、客观的参考依据.     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

Prise en charge des entorses externes de cheville : étude clinique préliminaire sur l’efficacité du dispositif Myolux™

Ankle sprains are the most common injury of the musculoskeletal system and are associated with significant societal and economic impacts. It has been proven that classical therapeutic strategies may not be effective in preventing recurrent injuries: the recurrence rates reported in the literature can reach 73%. In order to provide an effective rehabilitation solution, a destabilizing orthosis was developed. This device is equipped with a mechanical articulator reproducing the subtalar mechanics and placed under the heel. In this paper, we present the main results of a preliminary clinical study conducted between 2004 and 2007. All subjects included in this study were treated with the abovementioned orthosis during 10 rehabilitation sessions of 30 minutes each. Data show a relatively low recurrence rate of 12% for the overall population. Moreover, it's of primary importance to note that this satisfactory ratio is largely reduced (3% of recurrence rate) for the 29 patients who performed one training session per month after the 10th initial rehabilitation sessions. Hence, the destabilizing orthosis appears to be an effective solution to prevent recurrent ankle sprains. However, joint protection requires long-term and regular training sessions. This result has motivated the development of a similar device allowing patients to perform training sessions at home. Finally, data obtained in this study are promising awaiting the final results of the comparative, multicentric and independent clinical trials currently managed by the Hospices Civils de Lyon.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.