Submillimeter isotropic resolution carotid wall MRI with swallowing compensation: imaging results and semiautomated wall morphometry

PURPOSE: To assess a swallowing-compensated, three-dimensional (3D) diffusion-prepared segmented steady-state free precession (3D Nav-D-SSFP) technique for carotid wall MRI with 0.6-mm isotropic spatial resolution, and its utility for semiautomated carotid wall morphometry. MATERIALS AND METHODS: The carotid arteries of seven healthy volunteers (N=14) were imaged with 3D Nav-D-SSFP and black-blood T2-weighted (T2w) two-dimensional (2D) fast spin-echo (FSE). Carotid wall-lumen contrast-to-noise ratio (CNR) was measured with both sequences. Measurement of carotid wall area (WA) and lumen area (LA) made in a semiautomated manner off of the 3D Nav-D-SSFP images were compared to those made manually. RESULTS: Adjusted for voxel volume and number of slices, a near six-fold improvement in CNR per unit time was achieved with 3D Nav-D-SSFP relative to 2D T2w FSE (P<0.001). Manual and semiautomated measurements of carotid WA and LA on the 3D Nav-D-SSFP images were highly correlated (intraclass correlation coefficient (ICC)=0.961 and 0.996, respectively; P<0.001). CONCLUSION: 3D Nav-D-SSFP is a time-efficient, swallowing-compensated, black-blood technique that lends itself for semiautomated measurements of carotid WA and LA that are in good agreement with manual measurements.     

Multi-slice CT (MSCT) angiography for assessment of traumatic lesions of lower limbs peripheral arteries

Aim The aim of this study was to evaluate the feasibility and effectiveness of multi-slice computed tomography (MSCT) angiography for the assessment of traumatic lesions involving the arteries of the lower limbs. Materials and methods Forty-seven patients with suspected arterial post-traumatic lesions of lower limbs underwent MSCT angiography (4 × 2.5-mm collimation, 3-mm slice width). The standards of reference were: digital subtraction angiography (DSA; patients with inconclusive/doubtful or positive MSCT angiography indicating a need for intravascular treatment), surgical findings (patients with positive MSCT angiography indicating a need for surgery), or clinical/investigational follow-up (patients with negative MSCT angiography and no need for further diagnostic procedures or surgery). Results All CT exams were technically adequate. Sensitivity, specificity, and overall diagnostic accuracy of MSCT angiography were 96.3, 90, and 93.6%, respectively, relative to the reference of standard findings. In 44 out of 47 patients, MSCT angiography allowed a correct continuation of the diagnostic work-up. Conclusion MSCT angiography is a reliable fast tool for diagnosing traumatic vascular lesions, providing results comparable to DSA.     

Optimization of spatial resolution for peripheral magnetic resonance angiography

RATIONALE AND OBJECTIVES: To determine optimum spatial resolution when imaging peripheral arteries with magnetic resonance angiography (MRA). MATERIALS AND METHODS: Eight vessel diameters ranging from 1.0 to 8.0 mm were simulated in a vascular phantom. A total of 40 three-dimensional flash MRA sequences were acquired with incremental variations of fields of view, matrix size, and slice thickness. The accurately known eight diameters were combined pairwise to generate 22 "exact" degrees of stenosis ranging from 42% to 87%. Then, the diameters were measured in the MRA images by three independent observers and with quantitative angiography (QA) software and used to compute the degrees of stenosis corresponding to the 22 "exact" ones. The accuracy and reproducibility of vessel diameter measurements and stenosis calculations were assessed for vessel size ranging from 6 to 8 mm (iliac artery), 4 to 5 mm (femoro-popliteal arteries), and 1 to 3 mm (infrapopliteal arteries). Maximum pixel dimension and slice thickness to obtain a mean error in stenosis evaluation of less than 10% were determined by linear regression analysis. RESULTS: Mean errors on stenosis quantification were 8.8% +/- 6.3% for 6- to 8-mm vessels, 15.5% +/- 8.2% for 4- to 5-mm vessels, and 18.9% +/- 7.5% for 1- to 3-mm vessels. Mean errors on stenosis calculation were 12.3% +/- 8.2% for observers and 11.4% +/- 15.1% for QA software (P = .0342). To evaluate stenosis with a mean error of less than 10%, maximum pixel surface, the pixel size in the phase direction, and the slice thickness should be less than 1.56 mm2, 1.34 mm, 1.70 mm, respectively (voxel size 2.65 mm3) for 6- to 8-mm vessels; 1.31 mm2, 1.10 mm, 1.34 mm (voxel size 1.76 mm3), for 4- to 5-mm vessels; and 1.17 mm2, 0.90 mm, 0.9 mm (voxel size 1.05 mm3) for 1- to 3-mm vessels. CONCLUSION: Higher spatial resolution than currently used should be selected for imaging peripheral vessels.     

Hypertension induces compensatory arterial remodeling following arteriotomy

BACKGROUND: Hypertension has been traditionally considered a risk factor for restenosis following carotid arteriotomy. Genetic and morphological response to carotid arteriotomy in normotensive Wystar-Kyoto (WKY), spontaneously hypertensive (SHR), and Milan hypertensive (MHS) rats were analyzed. MATERIAL AND METHODS: C-myc, angiotensin II receptor-1 (AT1), angiotensin II receptor-2 (AT2), endothelin-1 receptor A (ET(A)), endothelin-1 receptor B (ET(B)), Bcl-2 family-members (Bcl-2/Bax, Bcl-X(L/S)) were analyzed in surgically injured as well as uninjured carotids of WKY and hypertensive strains (HS). Thirty-day histology and morphometry were accomplished on injured and uninjured carotids. RESULTS: C-myc mRNA is activated earlier and/or to a greater extent in hypertensive strains than in WKY. AT1 mRNA increases in WKY after injury, while it decreases in SHR and MHS. AT2 shows the opposite, decreasing in WKY and increasing in hypertensive strains. ET(A) mRNA decreases in all strains although with different timing and levels, associated with a replacement by ET(B) mRNA. Bcl-2/Bax ratio gradually decreases in WKY, while it shows only a transient decrease in SHR and MHS 4 h after the injury. Negative remodeling is observed in all injured carotids, although neointima was detected in WKY only. Thirty days following arteriotomy, morphometry demonstrated a significant decrease of luminal area, with consistent gain in the medial area in WKY, whereas hypertensive strains showed significant increase of the luminal area, consistent with a contemporary decrease of the medial area. CONCLUSIONS: Vaso-relaxant AT2 and ET(B) induced limited vasoconstriction in HS. Less apoptosis in hypertensive rats reduced cell proliferation, contrasting c-myc. These responses favorably modulated media/lumen area ratio following arteriotomy in HS.     

Glutamate release upon purinergic action in the dorsal facial area of the medulla increases blood flow in the common carotid artery in cats

Interactions of glutamatergic and purinergic actions in the medulla regulate important cardiovascular functions. The glutamatergic action in dorsal facial area (DFA) of the medulla increases blood flow of common carotid artery (CCA) in cats. We hypothesized that interactions of glutamatergic and purinergic actions in the DFA may regulate the CCA blood flow. Purinergic and glutamatergic agonists and antagonists were microinjected into the DFA through a four-barrel tubing in anesthetized cats. Drug effects were evaluated by changes in the CCA blood flow. Microinjection with 20 nmol ATP or α,β-methyleneATP (α,β-MeATP, a P2 purinergic receptor agonist) induced an increase of the CCA blood flow. This increase was dose-dependently reduced by prior administration with 1,3-dipropyl-8-p-sulfophenylxanthine (DPSPX, a specific P1 purinergic receptor antagonist), or pyridoxalphosphate-6-azophenyl-2′,4′-disulfonic acid (PPADS, a selective P2 purinergic receptor antagonist) as well as with MK-801 (a non-competitive NMDA receptor antagonist) or glutamate diethyl ester (GDEE, a competitive AMPA/kainate receptor antagonist). It was almost completely blocked by administrations with combined maximal doses of P1 and P2 receptor antagonists as well as NMDA and AMPA receptor antagonists. Nevertheless, P1 receptor agonist induced only mild and poorly reproducible increase in the CCA blood flow. In conclusion, prominent P2 and minor P1 purinergic receptors appear to be present in the DFA; the purinergic activation can mediate a release of glutamate that stimulates NMDA and AMPA to induce the increase of the CCA blood flows. These findings may provide important information for developing therapeutic strategy for diseases involving the CCA blood flow, such as hypertensive disease and cerebral ischemia.     

Angiographic demonstration of an aberrant abdominal umbilical artery in a patient with penoscrotal transposition and caudal regression

Penoscrotal transposition (PST) is a rare congenital anomaly characterized by caudal location of the penis with respect to the scrotum. PST may be seen in isolation or associated with caudal regression syndrome. We present a case of an infant born with penoscrotal transposition, bladder agenesis, a solitary dysplastic kidney, and caudal regression. The patient developed anuria and was referred for angiography for preoperative planning for renal transplantation and genital reconstruction. Angiography demonstrated an aberrant abdominal umbilical artery, an anomaly classically associated with sirenomelia but also has been described in caudal regression.     

动脉调转术195例冠状动脉分型及疗效分析

目的：总结行动脉调转手术（ASO）患者的冠状动脉分型,并探讨其相应的手术方法和疗效。方法：回顾分析2000年6月至2007年6月195例行ASO患者资料,其中室隔完整型大动脉转位（TGA／IVS）62例,室隔缺损型大动脉转位（TGA／VSD）86例,Taussing—Bing畸形（TBN）33例,先天性矫正型大动脉转位（CCTGA）14例。主动脉位于肺动脉右前98例（50．3％）,正前44例（22．6％）,左前37例（19．0％）,左右并列16例（8．2％）。采用Leiden冠状动脉分型方法对195例患者进行分类。ASO术中采用标准冠脉移植法179例,单窦主动脉冠状动脉片移植11例,冠状动脉旁路移植术（CABG）2例,其他移植方法3例。结果：1Lad,Cx;2R为冠脉正常分布,共139例（71．3％）,其他类型为冠脉异常分布,共56例（28．7％）。全组手术死亡25例,总死亡率为12．8％;冠状动脉正常分布者死亡率10．1％（14／139）,异常分布者死亡率19．6％（11／56）。5例患者死亡与冠状动脉异常分布相关。170例患儿存活,除1例发生脑缺氧昏迷后遗症外,余均痊愈出院。随访（14．5±7．6）个月,心功能明显改善。1例术后1年半因肺动脉吻合口狭窄再次手术,余患者无死亡和远期并发症发生。结论：目前多数常见冠脉异常分布的移植已取得满意效果,但壁内冠状动脉及罕见异常分布冠脉移植死亡率仍高,术中应仔细观察,注意避免发生冠脉损伤。     

咽鼓管鼓口的应用解剖学观测

目的：了解咽鼓管鼓口的解剖及其与周围结构之间的关系,探讨鼓口的解剖变异与咽鼓管相关疾病间的关系,为开展耳内镜手术提供解剖资料。方法：在12例24侧成人尸头标本上对咽鼓管鼓口的形态、鼓口与颈内动脉隆起之间关系进行观察,测量咽鼓管鼓口的内外径和上下径、锤骨柄距颈内动脉隆起和咽鼓管最狭窄处距离,颈内动脉隆起高度。结果：咽鼓管鼓口剖面均为喇叭形,其宽敞程度和颈内动脉隆起位置、高度密切相关;咽鼓管鼓口的内外径和上下径分别为（4．59±0．87）mm和（4．55±0．85）mm,锤骨柄距颈内动脉隆起距离为（4．13±1．25）mm,距咽鼓管最狭窄处距离为（13．89±2．29）mm,颈内动脉隆起高度为（2．26±1．55）mm。结论：颈内动脉隆起位置、高度影响咽鼓管鼓口的形态和引流功能,鼓口的引流和咽鼓管相关疾病的发生之间有一定的关系;因此在治疗咽鼓管相关疾病时一定要重视鼓口的解剖特点。     

CT灌注成像对颈内动脉闭塞与重度狭窄患者血流动力学的评价及临床意义

目的利用CT灌注成像了解症状性颈内动脉闭塞患者的血流动力学类型及其发病机制。方法连续选择2007年1月～2007年12月因缺血性脑血管病收入神经内科、经CT血管成像(CTA)证实为颈内动脉重度狭窄(≥70%)或闭塞的病人30例,其中颈内动脉闭塞14例,重度狭窄16例。脑梗死24例,TIA6例。所有病人入院24小时内完成CT灌注扫描。根据颈内动脉狭窄程度(重度狭窄或闭塞)及临床表现分组对脑血流灌注类型进行分析。结果发现3种灌注类型:Ⅰ型,大脑中动脉和/或大脑前动脉供血区的广泛低灌注(21例);Ⅱ型,仅病灶同侧局部边缘带低灌注(6例);Ⅲ型,灌注正常(3例)。无论颈内动脉有无闭塞,3种灌注类型均存在。脑梗死组患者脑血流灌注主要表现为Ⅰ型,而TIA组主要表现为Ⅱ型或Ⅲ型。结论颈动脉病变脑灌注类型与临床症状有关,而与颈内动脉有无闭塞关系不大。     

25例颈动脉内膜剥脱术临床分析及术中经颅多普勒超声监测体会

目的 探讨颈动脉内膜剥脱术（CEA）对颈动脉狭窄患者的疗效及术中经颅多普勒超声（TCD）监测经验总结。方法 回顾25例CEA手术患者的临床资料及术中TCD监测情况。结果 患者平均年龄64±10岁,男性23例,女2例。其中,左侧颈动脉狭窄11例（44%）,右侧13例（52%）,双侧狭窄而右侧较重者1例（4%）。除3例术中发生探头移位而未记录完整（均使用转流）外,余22例均全程监测。可根据CEA术中TCD监测大脑中动脉（MCA）血流速度变化了解术侧颈动脉远端供血情况,以确定是否转流。同时全程监测微栓子情况;术后有1例（4%）患者出现轻度神经系统缺损症状;2例（8%）出现谵妄;余22例（88%）未出现新发神经精神症状。结论 CEA可有效解除颈动脉狭窄及颈动脉易损斑块、降低卒中风险,术中TCD监测可为手术安全提供一定保障。