Sentinel node identification using microbubbles and contrast-enhanced ultrasonography

Sentinel lymph node (SLN) biopsy has become the recommended method for surgical staging of the axilla in patients with breast cancer. Grey-scale axillary ultrasonography (US) combined with US-guided biopsy is a widely used preoperative staging procedure but has limited sensitivity. US contrast agent "microbubbles", when injected intradermally, have been shown to have the potential to enter the breast lymphatics, travel rapidly to the axilla, and visualize the putative SLNs. This review illustrates the SLN identification technique using intradermal injection of microbubbles and contrast-enhanced US. The injection method, lymphatic visualization techniques, grey-scale and contrast-enhanced US images of the putative SLNs are reviewed and exemplified.     

Visualization of prostate cancer using dynamic contrast-enhanced MRI: comparison with transrectal power Doppler ultrasound

This study was designed to assess the efficacy of dynamic contrast-enhanced MRI (DCE-MRI), in comparison with power Doppler ultrasound (PDUS), for visualizing prostate cancer. 111 men suspected of having prostate cancer underwent imaging before undergoing octant biopsy. Subsequently, 31 cancer-positive patients were enrolled in this study. DCE-MRI was obtained using a three-dimensional fast-field echo sequence, which assured wide coverage of the prostate gland. The transrectal PDUS were scored according to the degree of power Doppler flow signals. The time intensity curve types for the DCE-MRI and the PDUS scores were compared with the histopathologic results for each region. The time intensity curves were correlated significantly with PDUS scores (p<0.001). Using PDUS, the overall sensitivity, specificity and accuracy of cancer visualization in peripheral zones were 69%, 61% and 66%, respectively. Using DCE-MRI, the corresponding values were 87%, 74% and 82%. In the inner gland, using PDUS, the overall sensitivity, specificity and accuracy were 68%, 94% and 83%, respectively. Using DCE-MRI, the corresponding values were similar (68%, 86% and 78%). DCE-MRI was significantly more sensitive than transrectal PDUS in peripheral zones (p<0.05). In conclusion, both transrectal PDUS and DCE-MRI can be used to demonstrate hypervascularity in many prostate cancers. DCE-MRI was significantly more sensitive than PDUS for visualizing of prostate cancers without loss of specificity in the peripheral zone.     

乳腺癌前哨淋巴结探查的研究进展

乳腺癌前哨淋巴结(sentinel lymph node, SLN)是乳腺癌淋巴转移通道中最先经历的第一级淋巴结。通过乳腺癌SLN预测乳腺癌区域淋巴结转移状况,为乳腺癌的准确分期和外科手术提供了重要的依据。根据示踪剂的不同,有两种方法可以探查乳腺癌SLN,其中使用放射性核素标记物作为示踪剂探查乳腺癌SLN是目前较具优势的方法,且不同于传统的淋巴显像;乳腺癌SLN探查的成功率受到诸多因素的影响,其探查技术亦需进一步的研究来提高。     

Sentinel node detection in pre-operative axillary staging

The concept of sentinel lymph node biopsy in breast cancer surgery is based on the fact that the tumour drains in a logical way via the lymphatic system, from the first to upper levels. Since axillary node dissection does not improve the prognosis of patients with breast cancer, sentinel lymph node biopsy might replace complete axillary dissection for staging of the axilla in clinically N0 patients. Sentinel lymph node biopsy would represent a significant advantage as a minimally invasive procedure, considering that about 70% of patients are found to be free from metastatic disease, yet axillary node dissection can lead to significant morbidity. Subdermal or peritumoural injection of small aliquots (and very low activity) of radiotracer is preferred to intratumoural administration, and (99m)Tc-labelled colloids with most of the particles in the 100-200 nm size range would be ideal for radioguided sentinel node biopsy in breast cancer. The success rate of radioguidance in localising the sentinel lymph node in breast cancer surgery is about 97% in institutions where a high number of procedures are performed, and the success rate of lymphoscintigraphy in sentinel node detection is about 100%. The sentinel lymph node should be processed for intraoperative frozen section examination in its entirety, based on conventional histopathology and, when necessary, immune staining with anti-cytokeratin antibody. Nowadays, lymphoscintigraphy is a useful procedure in patients with different clinical evidence of breast cancer.     

Comparative efficiency of contrast-enhanced colour Doppler ultrasound targeted versus systematic biopsy for prostate cancer detection

Objective  

To compare the efficiency of contrast-enhanced colour Doppler ultrasound (CECD-US) targeted biopsy versus systematic biopsy (SB) for PCa detection in 1,776 men.     

Experimental lymph node metastases: enhanced detection with MR lymphography

Magnetic resonance (MR) lymphography with superparamagnetic iron oxide (AMI-25) as a contrast agent was developed in an animal model with tumor-bearing lymph nodes. After interstitial administration of 20 mumol of iron per kilogram of body weight into the footpads of rats, the T2 of popliteal and paraaortic lymph nodes decreased from 67 msec +/- 8.2 to 9.5 msec +/- 0.9 and 9.3 msec +/- 0.9, respectively. T2 relaxation times of lymph nodes containing metastases showed a significantly higher value (61 msec +/- 6.2, P less than .005) after interstitial administration of the contrast agent. Intravenous administration of AMI-25 did not produce enhancement of normal or metastatic lymph node relaxation times. The signal intensity of normal lymph nodes decreased profoundly on spin-echo MR images (repetition time of 500 msec, echo time of 30 msec) after interstitial administration, whereas lymph nodes with metastases showed no significant change in signal intensity. Experimental results indicate that MR lymphography may potentially increase the sensitivity of MR imaging the detection of lymphatic malignancy.     

Therapeutic effect of transcatheter arterial chemoembolization on hepatocellular carcinoma: evaluation with contrast-enhanced harmonic power Doppler ultrasound

The aim of this study was to investigate the usefulness of contrast-enhanced harmonic power Doppler ultrasound (US) for the detection of residual viable hepatocellular carcinoma (HCC) after treatment with transcatheter arterial chemoembolization (TACE). Forty-seven patients with 68 HCC lesions 1.8–9.5 cm in diameter (mean ± SD 4.3 ± 1.7 cm) underwent contrast-enhanced power Doppler US, in the harmonic mode, before and after treatment with TACE. Unenhanced spiral CT and contrast-enhanced dynamic MR imaging were also performed to help establish the outcome of therapy. Before treatment, intratumoral blood flow signals were detected at contrast-enhanced harmonic power Doppler US in 65 (95 %) of 68 lesions. After TACE, flow signals were no longer detectable in 22 of these 65 lesions, which showed complete response at spiral CT and dynamic MR imaging. In 38 (88 %) of the 43 lesions with partial response, intratumoral flow signals were still identified at contrast-enhanced harmonic power Doppler US. Twenty-eight of these 38 lesions underwent additional treatment with percutaneous ethanol injection (PEI) using contrast-enhanced harmonic power Doppler US guidance. Complete response was seen after PEI in 23 of 28 lesions. Contrast-enhanced harmonic power Doppler US proved useful for assessing the therapeutic effect of TACE on HCC and for guiding additional treatment with PEI in cases of partial response. Received: 25 January 2000; Revised: 21 April 2000; Accepted: 25 April 2000     

超声造影与彩色多普勒超声诊断异位妊娠的对比研究

目的对比研究超声造影与彩色多普勒超声诊断异位妊娠的临床效果。方法回顾性分析2011年8月～2013年2月我院收治的100例异位妊娠患者的临床资料。结果 100例中,手术病理证实为异位妊娠的88例,经腹腔镜及刮宫病理证实宫内孕12例。超声造影诊断异位妊娠的敏感性为98.2%,特异性为80.0%,准确性为96.0%;彩色多普勒超声诊断异位妊娠的敏感性为86.2%,特异性为53.3%,准确性为81.4%,超声造影诊断异位妊娠的敏感性、特异性、准确性均明显比彩色多普勒超声高（P〈0.05）。结论超声造影比彩色多普勒超声诊断异位妊娠具有较好的临床效果,值得推广。     

Sentinel node detection by lymphoscintigraphy and sentinel lymph node biopsy in vulvar melanoma

Purpose

Vulvar melanoma is a rare malignant tumour. Its surgical excision is the mainstay of treatment whilst the surgical management of regional lymph nodes remains controversial; on the contrary elective inguinofemoral lymphadenectomy causes considerable morbidity. Lymphoscintigraphy (LS) and sentinel lymph node biopsy (SLNB) are accurate staging procedures of lymph node status in breast cancer and cutaneous melanoma patients. In this retrospective paper we report our experience of LS and SLNB in vulvar melanoma patients.

Methods

Twenty-two consecutive patients with a diagnosis of vulvar melanoma were treated at our institute: patients with clinically positive groin nodes or with previous surgery on the primary tumour were excluded. Twelve were selected for our analysis. All patients underwent sentinel lymph node localization with LS the day before surgery and the surgical procedure of SLNB associated with radical surgery.

Results

Six patients had metastatic SLNB and in five of six (83.3%) it was the only positive node. In the other six patients SLNB was negative for metastatic disease. No skip metastases were observed. In SLNB negative patients the mean Breslow thickness was 2.06 mm (range: 0.60–7.10) and only one patient showed a high Breslow thickness (patient 8). In SLNB positive patients the mean Breslow thickness was 4.33 mm (1.8–6.0).

Conclusion

Our data indicate that, even in vulvar melanoma, the sentinel lymph node pathological status predicts the pathological status of the remaining groin nodes and suggests that elective groin dissection can be spared in cases of a negative SLNB. Breslow thickness (<1 mm) was not predictive of negative nodes.     

Diagnostic utility of an echo-contrast agent in patients with synovitis using power Doppler ultrasound: a preliminary study with comparison to contrast-enhanced MRI

The purpose of this study was to first evaluate Levovist (Schering, Berlin, Germany), an echo-contrast agent, during power Doppler sonography (PDS) in patients with synovitis using asymptomatic joints as controls. Then we evaluated the accuracy of this technique against contrast-enhanced MRI. Forty patients (19 men and 21 women; mean age 40 years) were enrolled on the basis of clinical signs, laboratory tests, and radiographic findings positive for articular inflammatory disease. They were examined with conventional ultrasonography (US) and PDS techniques before and after intravenous contrast medium injection. Fourteen patients then underwent MRI with and without contrast medium 8–14 days after PDS studies. Three expert readers independently evaluated each examination. After contrast medium, synovium in inflammatory arthritis enhanced on PDS compared with normal joints in the same patient. Power Doppler sonography after contrast medium and MRI were concordant in all cases. Power Doppler sonography with contrast medium showed a qualitative increase in signal from synovial vessels, the first sign of synovial changes in inflammatory diseases. Received: 10 February 2000 Revised: 27 July 2000 Accepted: 1 August 2000     

Transvaginal power Doppler ultrasound in pelvic congestion

Purpose: 
Pelvic congestion is diagnosed by transuterine venography, an invasive procedure requiring sedation and irradiation. Ultrasound may be an alternative but is hindered by slow flow within pelvic veins. In an attempt to counter this, we investigated the possible role of transvaginal power Doppler ultrasound. Material and Methods: 
42 women with a clinical suspicion of pelvic congestion underwent transvaginal ultrasound. Adnexal veins were examined and a congestion score established. Planimetric measurements of adnexal vessels were obtained using power Doppler ultrasound, and uterine and ovarian morphology noted. All women then underwent transuterine venography and agreement with the ultrasound congestion score and morphologic features was determined. Results: 
There was a trend towards weak positive correlation between ultrasound and venography congestion scores (r = 0.29, p = 0.06). However, agreement between scores was poor on an individual basis (95% limits of agreement, -3.9 to +2.7). Planimetric power Doppler assessments of adnexal vascularity were unrelated to venographic congestion. Instead, there was correlation between the number and diameter of ovarian follicles and venographic congestion: women with congestion tended to have significantly more (0.04) and smaller follicles (p = 0.001). Conclusion: 
There was poor individual agreement between ultrasound and venographic estimates of congestion. However, there was a direct relationship between venographic congestion score and ovarian morphology.     

Automatic detection of bubbles in the subclavian vein using Doppler ultrasound signals

INTRODUCTION: It is possible to detect venous gas bubbles by listening to the Doppler audio signals. However, a serious disadvantage of the audio evaluation is the inability of continuous monitoring and the inter-rater agreement. Several researchers have worked on the automated detection of emboli, but no current system has the required sensitivity and specificity for clinical use. METHOD: We developed software that integrated frequency filtering, processing, and detection phases of microemboli into a graphical user interface. The detection algorithm consists of a rule-based criterion with a user-defined threshold sliding in-time axis that estimates the duration of the embolic event. Subclavian Doppler audio recordings obtained from a high altitude diving expedition were analyzed using digital filtering and non-linear operator combinations of the software. The data set includes 43 embolic events in 9 recordings from 4 different subjects. RESULTS: It was determined that embolic signals are best differentiated from the background signal at the 4500-8000-Hz frequency band. By using the non-linear "Teager Energy Operator", embolic signals were amplified against their background and a high level of sensitivity and specificity was obtained (83.7% and 97.3%, respectively). The duration of the detected emboli was estimated as 12.17 +/- 4.36 ms (mean +/- SD). DISCUSSION: The optimal frequency band for the detection of subclavian emboli is significantly higher than previous findings for the transcranial site. The duration output of the software can be used to estimate the size and the composition of emboli. Successful integration of the software into an ambulatory detection system may provide important site-specific bubble size distribution data for decompression modeling.     

SPECT-CT探测喉癌前哨淋巴结

目的 评价SPECT-CT淋巴显像探测喉癌患者前哨淋巴结(SLN)的价值。方法 30例临床N0期喉癌患者,术前于喉镜引导下注射99Tcm-硫胶体(SC),使用SPECT-CT进行SLN显像;同时,术中用γ探测仪探测放射性"热点"。将手术切除的SLN及颈清扫标本行病理检查。结果 全组30例检出SLN28例,检出率为93.3%。术前平面显像、SPECT-CT分别检出61个和66个SLN。术中用手持式γ探测仪有27例患者探测到SLN,共计70个,检出率为90.0%(27/30)。γ探测仪探测SLN数目与SPECT-CT淋巴显像数目有4例不一致,24例符合,其符合率为85.7%(24/28)。病理结果显示,6例患者有淋巴结转移,占20.0%。SLN检测的灵敏度、特异度、准确率和假阴性率分别为83.3%、95.8%、93.3%和16.7%。结论 术前SPECT-CT淋巴显像能有效探测喉癌患者的SLN,准确预测颈部淋巴结转移情况。