Gynecologic vascular abnormalities: diagnosis with Doppler US

The authors describe the use of duplex and/or color Doppler ultrasonography of the pelvis in three women to demonstrate the presence of venous malformations. One patient with a pulsatile vaginal mass was shown to have an arteriovenous malformation of the vaginal wall. The second patient was shown to have an unsuspected venous angioma in the endometrial cavity. The third patient was shown to have adnexal varices that closely mimicked hydrosalpinx. In the latter two cases, the duplex and color flow capabilities of an endovaginal probe were especially important.     

血管束植入在组织工程骨血管化构建中的作用

目的 观察以血管束植入法进行组织工程骨体内血管化构建的效果.方法 将以生物活性陶瓷β-磷酸三钙为基质材料、以培养扩增和成骨诱导后的兔骼骨骨髓基质干细胞为种子细胞复合构建组织工程骨.将组织工程骨植入兔股骨干15mm缺损区,同期在显微镜下进行血管束解剖分离并植入其内.以未做血管束植入动物作为对照.4周时行活体探查,12周时测骨密度并取材行大体观察和组织学观察.结果 植入血管处组织工程骨形成类似滋养孔的结构,血管双向通畅;植入血管束的组织工程骨受周围组织血管长入和血管束外生血管的双重营养.骨化方式:材料表面为膜内成骨,材料内为多骨化中心的软骨内成骨.骨密度测量结果显示血管束植入后组织工程骨新骨生长较未植入血管束者多.结论 血管束植入法可以加快组织工程骨在体内的生理性改建转化过程,是一种可行的组织工程骨血管化构建方法.     

Peripancreatic vascular abnormalities complicating acute pancreatitis: contrast-enhanced helical CT findings

OBJECTIVE: To determine the prevalence and morphologic helical computed tomography (CT) features of peripancreatic vascular abnormalities in patients with acute pancreatic inflammatory disease in correlation with the severity of the pancreatitis. MATERIALS AND METHODS: One hundred and fifty-nine contrast-enhanced helical CT scans of 100 consecutive patients with acute pancreatitis were retrospectively and independently reviewed by three observers. CT scans were scored using the CT severity index (CTSI): pancreatitis was graded as mild (0-2 points), moderate (3-6 points), and severe (7-10 points). Interobserver agreement for both the CT severity index and the presence of peripancreatic vascular abnormalities was calculated (K-statistic). Correlation between the prevalence of complications and the degree of pancreatitis was estimated using Fisher's exact test. RESULTS: The severity of pancreatitis was graded as mild (n = 59 scans), moderate (n = 82 scans), and severe (n = 18 scans). Venous abnormalities detected included splenic vein (SV) thrombosis (31 scans, 19 patients), superior mesenteric vein (SMV) thrombosis (20 scans, 14 patients), and portal vein (PV) thrombosis (17 scans, 13 patients). Arterial hemorrhage occurred in five patients (6 scans). In our series, no cases of arterial pseudoaneurysm formation were detected. The interobserver agreement range for scoring the degree of pancreatitis and the overall presence of major vascular abnormalities was 75.5-79.2 and 86.2-98.8%, respectively. The presence of the vascular abnormalities in correlation with the severity of pancreatitis was variable. CONCLUSION: Vascular abnormalities are relatively common CT findings in association with acute pancreatitis. The CT severity index is insufficiently accurate in predicting some of these complications since no statistically significant correlation between their prevalence and the severity of pancreatitis could be established.     

四肢深部软组织血管瘤和血管畸形的X线及MRI表现

目的：探讨四肢深部软组织血管瘤和血管畸形的 X 线及 MRI 表现。方法回顾性分析经手术病理及 DSA 证实的89例四肢深部软组织血管瘤和血管畸形患者的临床、影像资料,其中89例均行 X 线平片检查,33例行 MRI 检查。结果 X 线检查中,骨质及软组织影未见异常者54例(60.7%),软组织异常者14例(15.7%),可见静脉石者30例(33.7%);骨质异常者32例(36.0%),其中伴骨膜反应者13例,皮质破坏16例,髓腔受累者10例,三者均受累者为7例弥漫性病灶。MRI 图像上,病灶呈蜂窝状或海绵状,T1 WI 上呈等低信号者25例(75.8%),低信号5例(15.2%),不均匀稍高信号3例(9.0%);T2 WI 上病灶为不均匀高信号伴低信号分隔,范围及边界显示清楚,其中9例内部可见低信号区伴血管流空影;检出静脉石10例(30.3%),呈低信号;增强后病变不均匀明显强化。骨质异常者18例(54.5%),均可见病灶紧邻骨质或呈半包绕、包绕改变,其中12例髓腔内可见异常信号影,3例为迂曲血管流空影。在15例(45.5%)骨质无改变患者中,3例病灶邻接骨质,余12例病灶与骨间隔以脂肪或肌肉组织。结论四肢深部软组织血管瘤和血管畸形可引起邻近骨质的异常,掌握其 X 线及 MRI 表现特征,有助于提高对本病的诊断与鉴别诊断能力。     

Differentiation of vascular birthmarks by MR imaging. An investigation of hemangiomas, venous and lymphatic malformations

PURPOSE: To evaluate the use of MR imaging using standard sequences in the differentiation of common vascular birthmarks of soft tissues in childhood. MATERIAL AND METHODS: Forty-three lesions in 37 children (median age 33 months) with hemangiomas (n=25), venous (n=8) and lymphatic (n=10) malformations were retrospectively studied. Images were obtained with a 0.2 T and a 1.5 T MR unit, using T1-weighted spin-echo, T2-weighted turbo spin-echo and turbo STIR sequences. In addition, 19 contrast studies were evaluated. Signal intensities and morphological characteristics were analyzed. RESULTS: All hemangiomas were hyperintense in T2-weighted, and mostly (22/25) isointense compared to the surrounding skeletal muscle in T1-weighted images. The lesions were homogeneous or mildly inhomogeneous and well defined. Venous and lymphatic malformations showed similar patterns. Contrary to other lesions, no vessels or lobular architecture were detectable and contrast enhancement was absent in lymphatic malformations. CONCLUSION: A reliable differentiation between hemangiomas, venous and lymphatic malformations in childhood is not possible by standard MR sequences alone. Contrast media may be helpful as lymphatic malformations show no contrast enhancement. The main role of MR imaging is to determine the local extent or infiltration of deeper tissue layers and narrow the differential diagnosis of other soft tissue tumors.     

Demonstration of vascular abnormalities compressing esophagus by MDCT: special focus on dysphagia lusoria

PURPOSE: Dysphagia lusoria (DL) is described in the literature as difficulty in swallowing caused by vascular abnormalities. The most common cause is an aberrant right subclavian artery (SCA) which passes behind the esophagus and is also called arteria lusoria (AL). Our aim was to demonstrate the use of multidetector computed tomography (MDCT) in the diagnosis of AL, as there is no comprehensive study investigating the role of MDCT in such cases. MATERIAL AND METHODS: A total of 38 consecutive patients, comprising of 23 females (61%) and 15 males (39%), who had extrinsic compression were included in the study. These patients are selected from the cases who were admitted due to their gastrointestinal symptoms, such as dysphagia, epigastric pain, chronic nausea, vomiting, etc. The mean age of patients was 40 +/- 25 years (range 15-65). Following barium esophagogram and then endoscopy performed, MDCT angiography was carried out on the same or the following few days. MDCT sections were examined to determine the following: presence of vascular abnormality; the diameter and angle of that vascular structure; and the compressed area of esophagus. Radiological findings and dysphagia scores were also compared. RESULTS: In each of 15 cases, there was a compression due to vascular abnormality which were all located between the esophagus and the spine. There was an esophageal compression in each of 12 cases, due to right aberrant SCA, in one case due to right superior aortic arch and in two cases due to both right aortic arch and left SCA with Kommerell's diverticulum. The mean diameter and the angle of AL were 16.4 mm and 48.8 degrees , respectively, and the mean area of pressured esophagus was 194.7 mm2. Dysphagia scores of the cases was 1 in thirteen cases and 2 in two cases. However, dysphagia scores were not correlated with these parameters. CONCLUSIONS: MDCT angiography is a useful diagnostic tool for evaluation of patients with dysphagia, especially caused by a vascular abnormality.     

Mucocutaneous and peripheral soft-tissue hemangiomas: MR imaging

Hemangiomas are common congenital lesions that may have devastating sequelae. The extent and location of a lesion determines the therapeutic approach. We describe 11 patients with mucocutaneous or peripheral soft-tissue hemangiomas to illustrate the ability of magnetic resonance (MR) imaging to define clearly and noninvasively the extent and anatomic relationships of hemangiomas. The major advantage of MR imaging over computed tomography or angiography is the exquisite difference in contrast between hemangiomas and the surrounding structures on T2-weighted MR images, in which hemangiomas have a relatively intense signal. Hemangiomas demonstrated relatively low signal intensity (similar to muscle) on T1-weighted images, which were markedly inferior to T2-weighted images in defining the extent of the lesions. Phleboliths and feeding or draining vessels were rarely visible. The information obtained with MR imaging may be valuable clinically in planning surgical resection or laser therapy of aggressive lesions, in evaluating effectiveness of medical or embolic therapy, and in defining recurrence.     

Cutaneous vascular response and thermoregulation in individuals with paraplegia during sustained arm-cranking exercise

This study investigated whether a 60-minute arm-cranking exercise at 50% of the individual maximal power output would increase lower limb skin blood flow (laser Doppler flowmetry) in individuals with high-level (T5-T9; n = 6) and low-level paraplegia (T10-T12; n = 6), compared to 6 able-bodied controls. Significant (P < 0.05) group by time interactions (two-way repeated measures ANOVA) were found for leg cutaneous vascular conductance, leg skin temperature and esophageal temperature. Cutaneous vascular conductance increased to a peak of approximately 180% of pre-exercise rest in both paraplegic groups and to -436% in the control group, with differences after 15, 30, 45 and 60 minutes of exercise. Leg skin temperature increased by approximately 0.3 C in individuals with paraplegia and decreased by approximately 2.0 C in able-bodied. Esophageal temperature increases at the end of exercise were higher in individuals with paraplegia (approximately 0.9 C) than in able-bodied subjects (approximately 0.5 C). Heart rate was higher in the paraplegic groups than in able-bodied, whilst stroke volume and cardiac output were not different (impedance cardiography). The data suggest that lesion level had no influence on the results. These findings indicate that there is no excessive shunting of blood to the skin of the lower limbs of individuals with paraplegia during sustained exercise.     

Intracranial vascular abnormalities: value of MR phase imaging to distinguish thrombus from flowing blood

The interpretation of conventional spin-echo and gradient-echo MR images of intracranial vascular lesions can be complex and ambiguous owing to variable effects on image intensity caused by flowing blood or thrombus. MR phase images, obtained simultaneously with conventional-magnitude images, are useful for evaluating proton motion (i.e., blood flow), and therefore can simplify the diagnosis of the presence or absence of thrombosis within a vascular structure or lesion. Fourteen patients with a variety of intracranial vascular abnormalities (aneurysms, superior sagittal sinus thrombosis, neoplasms adjacent to venous sinuses, and vascular malformations) were evaluated with conventional MR and phase imaging for the presence of blood flow. The phase images correlated with angiography in all cases. Phase imaging was not necessarily better than conventional spin-echo imaging in all cases, but it simplified the evaluation of thrombus vs blood flow in many. In three of five aneurysms, the phase images were diagnostic for evaluating lumen patency whereas the conventional images were ambiguous. Phase imaging was advantageous for detecting tumor invasion of the venous sinus when venous blood was enhanced by gadopentetate dimeglumine. A laminar flow phantom experiment determined the lower limits of sensitivity of phase imaging to be 0.5 cm/sec in the slice-select and 2.5 cm/sec in the read gradient directions. Phase imaging is a simple, reliable technique that can distinguish thrombosis from flowing blood within intracranial lesions. It is easily performed and adds no additional time to the MR examination.     

Color Doppler US in the evaluation of uterine vascular abnormalities.

Uterine vascular lesions are rare but potentially life-threatening lesions that should be suspected in women of reproductive age with unexplained vaginal bleeding and in postmenopausal women in whom anechoic structures are detected at ultrasonography (US). This is especially true in patients with a history of infection, curettage, therapeutic abortion, pelvic surgery, endometrial carcinoma, or gestational trophoblastic disease. Color Doppler US is valuable in the detection and characterization of many uterine vascular lesions, including arteriovenous malformations (AVMs) (especially arteriovenous fistulas), true aneurysms, pseudoaneurysms, and chorioangioma of the placenta. Arteriovenous fistulas demonstrate a mosaic pattern representing turbulent flow. Spectral analysis of intralesional arterial flow demonstrates high-velocity flow with a low resistive index, and spectral analysis of intralesional venous flow shows high peak systolic velocities consistent with an arterial flow pattern. Spectral analysis of a true aneurysm demonstrates arterial signals, whereas a to-and-fro or swirling pattern of flow is seen at the neck of a pseudoaneurysm. Chorioangioma is a benign hypervascular lesion with arterial and venous flow that, like AVMs, contains numerous cystic spaces that produce color signals. Color Doppler US is useful in the early diagnosis and treatment of these potentially clinically significant disorders of the uterus and placenta. Response to treatment can also be assessed with this technique.     

Non-invasive MR assessment of macroscopic and microscopic vascular abnormalities in the rectal tumour-surrounding mesorectum

Objectives

To evaluate the MRI macroscopic and microscopic parameters of mesorectal vasculature in rectal cancer patients.

Methods

Thirteen patients with rectal adenocarcinoma underwent a dynamic contrast-enhanced MRI at 1.5 T using a blood pool agent at the primary staging. Mesorectal macrovascular features, i.e., the number of vascular branches, average diameter and length, were assessed from baseline-subtracted post-contrast images by two independent readers. Mesorectal microvascular function was investigated by means of area under the enhancement-time curve (AUC). Histopathology served as reference standard of the tumour response to CRT.

Results

The average vessel branching in the mesorectum around the tumour and normal rectal wall was 8.2?±?3.8 and 1.7?±?1.3, respectively (reader1: p?=?0.001, reader2: p?=?0.002). Similarly, the tumour-surrounding mesorectum displayed circa tenfold elevated AUC (p?=?0.01). Interestingly, patients with primary node involvement had a twofold higher number of macrovascular branches compared to those with healthy nodes (reader1: p?=?0.005 and reader2: p?=?0.03). A similar difference was observed between good and poor responders to CRT, whose tumour-surrounding mesorectum displayed 10.7?±?3.4 and 5.6?±?1.5 vessels, respectively (reader1/reader2: p?=?0.02).

Conclusions

We showed at baseline MRI of rectal tumours a significantly enhanced macrovascular structure and microvascular function in rectal tumour-surrounding mesorectum, and the association of primary mesorectal macrovascular parameters with node involvement and therapy response.

Key Points

? Vascular MRI reveals macrovascular and microvascular abnormalities in the rectal tumour-surrounding mesorectum. ? Formation of highly vascular stroma precedes the actual tumour invasion. ? High macrovascular parameters are associated with node involvement. ? Mesorectal vascular network differs for good and poor responders.

     

Tc-99m-labeled red blood cells in the evaluation of vascular abnormalities

Scintigraphy with Tc-99m-labeled red blood cells was used to evaluate five patients with suspected vascular abnormalities. The technique was useful for the imaging of large areas of the body and in obtaining multiple views. Conventional radionuclide angiography is of limited usefulness in such cases.