Real-time contrast enhanced ultrasound imaging of focal splenic lesions

Objective

To investigate the imaging features of focal splenic lesions (FSLs) on contrast-enhanced ultrasound (CEUS).

Methods

Thirty two patients with FSLs proved by pathology were retrospectively analyzed. CEUS was performed using intravenous bolus injection of 2.4 ml sulfur hexafluoride-filled microbubble contrast agent and real time scanning. There were hemangioma (n = 7), lymphoma (n = 8), true cyst (n = 3), infarction (n = 4), hematolymphangioma (n = 2), metastasis tumor (n = 2), and one for each of the following entities extramedullary hemopoiesis, hamartoma, tuberculosis, Langerhans’ cell histiocytosis, inflammatory pseudotumor and myxofibrosarcoma.

Results

Among 21 benign lesions, 4 infarctions and 3 cysts presented non-enhancement throughout CEUS scanning, and the other 14 lesions displayed various enhancement levels with 6 (42.9%) hyper-enhancement, 2 (14.3%) iso-enhancement and 6 (42.9%) hypo-enhancement in arterial phase and 11 (78.6%) hypo-enhancement, 1 (7.1%) iso-enhancement and 2 (14.3%) hyper-enhancement in late phase, respectively. The enhancement pattern included 9 (64.3%) homogeneous, 4 (28.6%) heterogeneous and 1 (7.1%) rim-like enhancement. As for the malignant FSLs, all the lesions became completely or extensively hypo-enhancement during the late phase no matter their vascularity during arterial phase.

Conclusions

The CEUS features reported in this series may enrich the knowledge for CEUS characterization of FSLs.     

Post-splenectomy demonstration of splenic tissue by computed tomography with liposoluble contrast material

The significance of localizing accessory spleens in patients with hematologic disorders as well as demonstrating splenic regeneration following splenectomy is well recognized. An experimental contrast material has been developed that, after intravenous injection, selectively opacifies the liver and spleen on computed tomograms. The contrast material was primarily developed to detect small avascular liver lesions (metastases). Its value in detecting accessory or recurrent spleen was recognized incidentally when a patient with testicular carcinoma and a previous splenectomy showed opacification of splenic tissue in the left upper abdomen.     

超选择性动脉栓塞治疗肝脾损伤出血

目的探讨经导管超选择性动脉栓塞治疗肝脾损伤出血的方法、疗效及安全性。方法本组肝损伤出血7例,脾损伤出血11例,采用股动脉穿刺插管技术,将导管超选择性插管至肝或脾动脉出血分支内,缓慢注射明胶海绵颗粒行栓塞治疗。动脉分支有假性动脉瘤形成者4例,在明胶海绵栓塞治疗后以弹簧圈栓塞出血分支近端。术后密切观察患者生命体征、有无再出血征象及术后反应、并发症发生等情况。结果18例均成功实施超选肝脾动脉分支栓塞治疗,术后患者无再出血发生,病情好转。治疗后患者均无明显不良反应,无严重并发症发生。结论超选择性动脉栓塞治疗肝脾损伤出血是一种安全、易行、有效的治疗方法,可尽量避免外科手术,保留了患者的脏器及功能。     

Contrast-enhanced ultrasound imaging of active bleeding associated with hepatic and splenic trauma

Purpose

The aim of this study was to evaluate contrast-enhanced ultrasound (CEUS) imaging of active bleeding from hepatic and splenic trauma.

Materials and methods

Three hundred and ninety-two patients with liver or/and spleen trauma (179 liver and 217 spleen injuries), who underwent CEUS examinations following contrast-enhanced computed tomography (CT), were enrolled in this retrospective study over a period of >4 years. CEUS detected contrast medium extravasation or pooling in 16% (63/396) of liver or spleen lesions in 61 patients, which was confirmed by contrast-enhanced CT. Special attention was paid to observing the presence, location, and characteristics of the extravasated or pooled contrast medium.

Results

The CEUS detection rate for active bleeding was not different from that of contrast-enhanced CT (p=0.333). Information from surgery, minimally invasive treatment and conservative treatment was used as reference standard, and the sensitivities of the two techniques were not different (p=0.122). Of 63 lesions in 61 patients, CEUS showed that 74.6% (47/63) (21 liver lesions and 26 spleen lesions) presented contrast medium extravasation or pooling, both in the organ and out the capsule, in 14.3% (9/63) and only outside the capsule in 11.1% (7/63). CEUS imaging of active bleeding from hepatic and splenic trauma presented various characteristics, and the sizes and shapes of the active bleeding due to contrast medium extravasation or pooling were variable.

Conclusions

CEUS can show the active bleeding associated with hepatic and splenic trauma with various imaging characteristics, thus making it possible to diagnose active bleeding using CEUS.     

Wideband harmonic imaging: a novel contrast ultrasound imaging technique

A novel ultrasonic imaging method, wideband harmonic imaging, for nonlinear imaging of microbubble contrast agents is evaluated. In wideband harmonic mode, two pulses of alternate phase are send out. The image is then processed from the sum of both pulses, resulting in an image of nonlinear scatterers such as microbubbles. A prototype ultrasound system, Siemens Elegra, was evaluated with in vitro investigations and animal trials, using conventional, harmonic and wideband harmonic settings with the galactose based ultrasound contrast agent Levovist. Wideband harmonic imaging offers superior sensitivity for ultrasound contrast agents compared to conventional imaging and harmonic imaging. At low transmit power settings (MI 0. 1-0.5) the nonlinear response is already sufficient to generate a image of the blood pool distribution of Levovist in the rabbit kidney including the microvasculature, with clear delineation of vessels and perfused parenchyma. At high transmit amplitudes, nonlinear tissue response reduced the apparent image contrast between contrast agent and tissue. The results suggest that wideband harmonic imaging is currently the most sensitive contrast imaging technique, maintaining highest spatial resolution. This may add to image quality and offer new clinical potential for the use of ultrasound contrast agents such as Levovist.     

Microbubbles as ultrasound contrast agents for molecular imaging: preparation and application

OBJECTIVE: The purpose of this review is to describe trends in microbubble application in molecular imaging. CONCLUSION: Microbubbles are used for contrast ultrasound imaging as blood-pool agents in cardiology and radiology. Their promise as targeted agents for molecular imaging is now being recognized. Microbubbles can be functionalized with ligand molecules that bind to molecular markers of disease. Potential clinical applications of molecular imaging with microbubble-based ultrasound contrast agents are in the monitoring of the biomarker status of vascular endothelium, visualizing tumor vasculature, and imaging inflammation and ischemia-reperfusion injury zones and thrombi.     

超声造影在肝脏疾病中的应用进展

随着一代代新型超声对比剂的相继问世和造影成像技术的不断发展 ,超声造影成像已成为超声医学界关注的热点 ,其在肝脏疾病诊断、鉴别诊断与肝肿瘤非手术治疗疗效监测中的应用不但广泛 ,而且具有独到的优点和重要的临床价值。本文综合文献资料 ,对超声对比剂与成像技术加以概括 ,并将超声造影在肝脏疾病中的临床应用现状与进展进行综述。     

外伤性脾破裂脾动脉栓塞的治疗

外伤性脾破裂脾动脉栓塞既保留了脾脏又阻止了脾脏继续出血,临床效果良好。本文介绍最近几年外伤性脾破裂的基础与临床研究。     

超声动态监测在外伤性脾破裂非手术治疗中的应用

目的探讨超声动态监测在外伤性脾破裂非手术治疗中的应用价值。方法对25例外伤性脾破裂患者进行非手术治疗,超声动态监测重点观察脾脏回声和腹腔积液等情况,并严密监测临床体征。结果 25例患者中诊断为真性脾破裂14例,中央性脾破裂5例,包膜下脾破裂6例;首次超声检查确诊16例,经超声动态监测确诊9例。其中22例患者经非手术治疗成功,超声复查提示脾内血肿缩小或基本吸收,腹腔积液减少或消失;3例患者经超声动态监测后确认非手术治疗无效而中转急诊手术。结论超声动态监测脾内损伤情况及腹腔内积血的变化,能直观、实时地显示外伤性脾破裂非手术治疗中的病情进展情况;早期阶段实施床边超声检查有助于提高非手术治疗的成功率,而对可疑者进行超声动态监测则有助于尽早确诊。综合临床体征观察和超声动态监测可作为外伤性脾破裂非手术治疗的首选监测手段。     

Microbubble ultrasound contrast agents: an update

Microbubble contrast agents for ultrasound (US) have gained increasing interest in recent years, and contrast-enhanced US (CEUS) is a rapidly evolving field with applications now extending far beyond the initial improvements achieved in Doppler US. This has been achieved as a result of the safe profile and the increased stability of microbubbles persisting in the bloodstream for several minutes, and also by the availability of specialized contrast-specific US techniques, which allow a definite improvement in the contrast resolution and suppression of signal from stationary tissues. CEUS with low transmit power allows real-time scanning with the possibility of prolonged organ insonation. Several reports have described the effectiveness of microbubble contrast agents in many clinical applications and particularly in the liver, spleen, and kidneys. CEUS allows the assessment of the macrovasculature and microvasculature in different parenchymas, the identification and characterization of hepatic and splenic lesions, the depiction of septal enhancement in cystic renal masses, and the quantification of organ perfusion by the quantitative analysis of the echo-signal intensity. Other fields of application include the assessment of abdominal organs after traumas and the assessment of vesico-ureteral reflux in children. Finally, tumor-targeted microbubbles make possible the depiction of specific biologic processes.     

Abnormal uterine bleeding: the role of ultrasound

Abnormal uterine bleeding is an important clinical concern and accounts for much medical intervention. This article presents an ultrasound-based approach to help exclude endometrial carcinoma and identify the source of bleeding for better clinical management. Saline infusion sonohysterography can help to triage patients to (1) no anatomic pathology, (2) globally thickened anatomic pathology that may be evaluated with blind endometrial sampling, or (3) focal abnormalities that must be evaluated under direct vision.