Differentiation between benign and metastatic cervical lymph nodes with ultrasound

The Applications and Potential Developments of Ultrasound in Oral Cancer Management

Oral cancer is endemic and causes a great burden in Southern Asia. It is preferably treated by surgery with/without adjuvant radiotherapy (RT) or chemoradiation therapy, depending on the stage of the disease. Close or positive resection margin and cervical lymph node (LN) metastasis are important prognostic factors that have been presented to be related to undesirable locoregional recurrence and poor survival. Ultrasound (US) is a simple, noninvasive, time-saving, and inexpensive diagnostic modality. It can depict soft tissues very clearly without the risk of radiation exposure. Additionally, it is real-time and continuous image is demonstrated during the exam. Furthermore, the clinician can perform US-guided fine needle aspiration (FNA) or core needle biopsy (CNB) at the same time. US with/without US-guided FNA/CNB is reported to be of value in determining tumor thickness (TT), depth of invasion (DOI), and cervical LN metastasis, and in aiding the staging of oral cancer. DOI has a relevant prognostic value as reported in the eighth edition of the American Joint Committee on Cancer staging of oral cancer. In the present review, we describe the clinical applications of US in oral cancer management in different phases and potential applications in the future. In the pretreatment and surgical phase, US can be used to evaluate TT/DOI and surgical margins of oral cancer in vivo and ex vivo. The prediction of a malignant cervical LN (nodal metastasis) by the US-based prediction model can guide the necessity of FNA/CNB and elective neck dissection in clinical early-stage oral cancer. In the posttreatment surveillance phase, US with/without US-guided FNA or CNB is helpful in the detection of nodal persistence or LN recurrence, and can assess the possibility and extent of carotid artery stenosis after irradiation therapy. Both US elastography and US swallowing assessment are potentially helpful to the management of oral cancer.

Morphometric evaluation of canine hepatocellular carcinoma using computed tomography: a promising tool for predicting malignancy

The size of canine focal liver lesions (FLLs) is known to be one of the predicting criteria for malignancy. However, there are discrepancies for the measurement of maximum lesion size, resulting in contradicting results among studies and incidences of false positive outcomes. Thus far, the morphometric changes of FLLs for distinguishing malignancy from benignancy remains undocumented. This study aimed to investigate morphometric characteristics of FLLs using computed tomography (CT). CT images of 40 dogs with histopathological confirmation of 49 liver lesions, including 39 hepatocellular carcinomas and 10 nodular hyperplasias were retrospectively reviewed. The morphometric parameters including size (long and short axis diameters measured on transverse image), shape (measured by long to short axis (L/S) ratio), volume, and surface appearance of a liver lesion were evaluated using univariate and stepwise multivariate analyses, respectively. The results of univariate analysis showed that long and short axis diameters, L/S ratio, volume, and surface appearance of a lesion were significantly different between hepatocellular carcinomas and nodular hyperplasias. Multivariate analysis revealed that short axis diameter (>3.30 cm; odds ratio (OR): 36.1, 95% confidence interval (CI): 3.36–387.05, P=0.0031) and L/S ratio (>1.23; OR: 18.1, 95% CI: 1.61–205.12, P=0.0191) were independent predictors of malignancy, with the area under the curve of 0.9154. These results suggest that the combination of short axis diameter and L/S ratio is a promising tool for predicting liver malignancy with outstanding discriminating ability.

Efficacy of Computed Tomography and Ultrasonography in Diagnosis of Metastatic Cervical Lymph Nodes in Orofacial Cancer

INTRODUCTION

There is no consensus on which imaging modality is better for the detection of metastatic cervical lymph nodes in orofacial malignancies. This study evaluates the efficacy of computed tomography (CT) and ultrasonography (US) in diagnosis of metastatic cervical lymph nodes in orofacial cancer.

MATERIALS AND METHODS

Sixty patients with various histologically diagnosed orofacial malignant lesions and clinical evidence of cervical lymph node metastasis were examined using US and CT. Further, the affected lymph nodes were biopsied and examined histologically. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of the techniques were calculated. The data was analyzed using Statistical Package for Social Sciences (SPSS) version 19 (SPSS Inc., Chicago, IL, USA) and Microsoft Excel 2010 (Microsoft, Redmond, WA, USA). Test of statistical significance was set at 0.05.

RESULTS

US recorded a sensitivity, specificity, PPV, NPV, and accuracy of 80.0%, 57.1%, 77.5%, 60.0%, and 71.7%, respectively (P = 0.004), while CT recorded a sensitivity, specificity, PPV, NPV, and accuracy of 87.1%, 71.4%, 85.0%, 75.0%, and 81.7%, respectively (P< 0.0001). Lymph node size was the commonest criterion in the diagnoses of metastases in cases with cervical lymph nodes.

CONCLUSION

Although we obtained great results using US, our results indicated CT to be a better imaging modality for detecting metastatic cervical lymph nodes in orofacial malignancies.

B-mode ultrasound, color Doppler, and sonoelastography in differentiation between benign and malignant cervical lymph nodes with special emphasis on sonoelastography

Background

Enlarged cervical lymph nodes are the most commonly encountered neck lumps. Ultrasonography is the most extensively used tool for classification of superficial lymph nodes due to its availability and low cost. Ultrasound (US) elastography refers to a non-invasive imaging technique that can describe tissue displacement (i.e., strain) or stiffness in response to a given force.

The aim of this study is to compare between B-mode sonography, color Doppler, and sonoelastography in assessment of enlarged deep cervical lymph nodes.

Results

The prevalence of benign lymph nodes was 26 out of 84 (31%). Lymphomatous lymph nodes were 22/84 (26.2%), while metastatic lymph nodes were 36/84 (42.8%). Color Doppler evaluation of nodal vascular pattern was of high sensitivity (91.7%), specificity (80.8%), and accuracy (88.6%) for differentiating metastatic and benign nodes (P value was < 0.001). There was a significant difference between elasticity scores of benign and malignant lymph nodes (P < 0.001). The most frequent score in the malignant group was 3 (21/27) (77.8%) while the most frequent score in the benign group was 2 (5/11) (45.5%). The mean strain ratio (strain index) for malignant lymph nodes (mean 3.2 ± 0.8) was significantly greater than that for benign lymph nodes (mean 1.1 ± 0.8).

Conclusion

Ultrasound elastography with its high sensitivity and specificity is a helpful improvement in US for the assessment of cervical lymph nodes, in which biopsies should be performed.

Computed tomography of thoracic lymph nodes in 100 dogs with no abnormalities in the dominated area

In dogs, reports on thoracic lymph nodes are lacking compared to abdominal lymph nodes. This report analyzed the position, number, size, shape, and homogeneity of thoracic lymph nodes (cranial sternal, cranial mediastinal, tracheobronchial, aortic thoracic, and pulmonary lymph nodes) using thoracic computed tomography (CT) images of 100 dogs without any lesions in the dominated areas of thoracic lymph nodes. The position and number of intrathoracic lymph nodes could be observed in CT, consistent with macroscopic anatomical studies. It was difficult to set a clinical index associated with size using CT scans. Image findings that indicated abnormalities, such as circular shapes and non-uniform, may be routinely found in dogs and may not be considered abnormal on CT scans.

Differentiation Between Benign and Metastatic Cervical Lymph Nodes Using Ultrasound

Purpose

The oral cavity is the most common site for squamous cell carcinoma, which has a distinct predilection for lymphatic spread before distant systemic metastasis. The cervical lymph node status is a very important consideration in the assessment of squamous cell carcinoma. Ultrasound is a noninvasive and inexpensive technique that can be used to differentiate between the benign and metastatic nodes. So the aim of this study was to evaluate reliability of ultrasound for such differentiation and to correlate them with histopathological finding.

Materials and Methods

A total of 200 lymph nodes from 38 patients histopathologically proven for oral squamous cell carcinoma who underwent surgical neck dissection were considered. The patients underwent ultrasound examination of cervical lymph nodes prior to surgical neck dissection. The lymph nodes were differentiated into benign and metastatic based on the assessment of size, shape, shortest diameter/longest diameter (S/L ratio), margin, and internal architecture, and also the internal echo structure of the lymph nodes and histopathological findings were analyzed.

Results

On correlation of ultrasonographic diagnosis with histopathological evaluation for metastatic lymph nodes, the overall accuracy of ultrasonographic analyses was 77.83%, and the sonographic criterion of irregular margin showed the highest predictability followed by the size. The correlation of internal echo structure with histopathological findings was highly variable.

Conclusion

The ultrasound parameters such as size, shape, margin, S/L ratio, and internal echo structure might assist in differentiation between benign and metastatic lymph nodes. Combining these findings should raise the accuracy, as each sonographic parameter has some limitation as a sole criterion.

Ultrasonographic Appearances of Cervical Lymph Nodes in Healthy Turkish Adults Subpopulation: Preliminary Study

Objectives:

The aim of the study was to assess whether there was any relation between age, gender and body mass index (BMI) and nodal forms and vascular type in healthy Turkish adults.

Study Design:

Three neck areas in 25 wholesome patients who were aged from 21 to 58 years, were assessed by gray-scale and color doppler ultrasonography. Ultrasonographic examinations were performed using an ALOKA Prosound Alpha 6 (Hitachi Aloka Medical Systems, Tokyo, Japan) and the images were obtained with a 7.2 MHz linear array transducer. Hajek’s categorization of cervical lymph nodes for sonographic analysis was used. The ultrasonographic characteristics like size, shape, short axis/long axis ratio (S/L), hilum were evaluated. Ultrasonographic examinations of upper cervical, submandibular and submental lymph nodes were carried out and recorded.

Results:

The mean age of patients was 31.84±12.80 years. The ratios of lymph nodes with avascular pattern were 96% for the upper cervical lymph area, 92% for the submandibular area and 96% for the submental area. The lowest and highest ratios of short to long axis diameter (S/L) were calculated as 0.18 and 0.66 in all areas. Most normal nodes in the study were oval with an S/L ratio of less than 0.5.

Conclusion:

Normal cervical lymph nodes are oval, with an unsharp border and an echogenic hilum but no relation between the age, gender and BMI. Also ultrasonography is an applicable imaging modality for the examination of cervical lymph nodes. However, the deficiency in the number of patients might not allow to generalise our findings to the general populations.

Ultrasonographic Evaluation of Cervical Lymph Nodes in Thyroid Cancer

Objective To determine what ultrasonographic features can identify metastatic cervical lymph nodes, both preoperatively and in recurrences after complete thyroidectomy. Study Design Prospective. Setting Outpatient clinic, Department of Head and Neck Surgery, School of Medicine, University of São Paulo, Brazil. Subjects and Methods A total of 1976 lymph nodes were evaluated in 118 patients submitted to total thyroidectomy with or without cervical lymph node dissection. All the patients were examined by cervical ultrasonography, preoperatively and/or postoperatively. The following factors were assessed: number, size, shape, margins, presence of fatty hilum, cortex, echotexture, echogenicity, presence of microcalcification, presence of necrosis, and type of vascularity. The specificity, sensitivity, positive predictive value, and negative predictive value of each variable were calculated. Univariate and multivariate logistic regression analyses were conducted. A receiver operator characteristic (ROC) curve was plotted to determine the best cutoff value for the number of variables to discriminate malignant lymph nodes. Results Significant differences were found between metastatic and benign lymph nodes with regard to all of the variables evaluated ( P < .05). Logistic regression analysis revealed that size and echogenicity were the best combination of altered variables (odds ratio, 40.080 and 7.288, respectively) in discriminating malignancy. The ROC curve analysis showed that 4 was the best cutoff value for the number of altered variables to discriminate malignant lymph nodes, with a combined specificity of 85.7%, sensitivity of 96.4%, and efficiency of 91.0%. Conclusion Greater diagnostic accuracy was achieved by associating the ultrasonographic variables assessed rather than by considering them individually.

Role of Real-Time Elastography in the Evaluation of Cervical Lymph Nodes in Patients with Kikuchi Disease

The purpose of this study was to compare the use of conventional ultrasound (US) and real-time elastography (RTE) in Kikuchi disease (KD, n = 48) and malignant cervical lymphadenopathy (n = 100) and to evaluate the role of RTE in patients suspected of having KD. In univariate analysis, conventional US revealed each benign feature more frequently in KD than in malignant lymphadenopathy (p < 0.05). However, a considerable number of cases (29, 60.4%) of KD were assessed as malignant with US. KD was assessed as benign by RTE more frequently than malignant lymphadenopathy (37 [77.1%] vs. 37 [37.0%], p < 0.001). In multivariate analysis, perinodal hyper-echogenicity was predictive of KD (odds ratio: 67.25, confidence interval: 10.95-413.04, p < 0.001). There was a tendency for KD to be assessed as malignant with conventional US, but benign with RTE. RTE can help to avoid unnecessary biopsy in patients suspected of having KD on the basis of conventional US.

Application of Computer-Aided Diagnosis to the Sonographic Evaluation of Cervical Lymph Nodes

We initiated an observer study to evaluate a computerized system developed in our previous study for automatic extraction of 10 features and estimation of the malignancy probability of cervical nodes in sonograms. In the present study, five expert radiologists and five resident radiologists interpreted the sonograms of 178 nodes. The malignancy rating and patient management recommendation (biopsy or follow-up) were made without and then with the computer aid. Under these two reading conditions, the performances of radiologists and agreement among a group of radiologists were evaluated by using the receiver operating characteristic (ROC) analysis and the κ statistic, respectively. With the computer aid, the performances of radiologists improved significantly, as indicated by the increase in the area under the ROC curve (Az) from 0.843 to 0.896 (p = 0.031) and from 0.705 to 0.822 (p < 0.001), for the expert and resident groups, respectively. Agreement among all 10 radiologists improved from slight to moderate as indicated by an increase in the κ value from 0.195 to 0.421 (p < 0.001). The average performance of residents with aid (Az = 0.822) was close to that of experts without aid (Az = 0.843). Results indicate that computer-aided diagnosis is useful to improve radiologist performance (especially that of inexperienced radiologists) in the ultrasonographic evaluation of cervical nodes and to reduce variability among radiologists.

Direct delivery of a cytotoxic anticancer agent into the metastatic lymph node using nano/microbubbles and ultrasound

Direct injection of an anticancer agent into a metastatic lymph node (LN) has not been used as a standard treatment because evidence concerning the efficacy of local administration of a drug into a metastatic LN has not been established. Here we show that the combination of intralymphatic drug delivery with nano/microbubbles (NMBs) and ultrasound has the potential to improve the chemotherapeutic effect. We delivered cis-diamminedichloroplatinum (II) (CDDP) into breast carcinoma cells in vitro and found that apoptotic processes were involved in the antitumor action. Next, we investigated the antitumor effect of intralymphatic chemotherapy with NMBs and ultrasound in an experimental model of LN metastasis using MXH10/Mo-lpr/lpr mice exhibiting lymphadenopathy. The combination of intralymphatic chemotherapy with NMBs and ultrasound has the potential to improve the delivery of CDDP into target LNs without damage to the surrounding normal tissues. The present study indicates that intralymphatic drug delivery with NMBs and ultrasound will potentially be of great benefit in the clinical setting.

The combination of intralymphatic chemotherapy with ultrasound and nano-/microbubbles is efficient in the treatment of experimental tumors in mouse lymph nodes

Intravenous chemotherapy is a therapeutic option for the treatment of lymph node metastasis, but the drugs often have difficulty accessing the lymphatic system. The aim of this study was to determine whether the combination of intralymphatic chemotherapy with ultrasound and nano-/microbubbles is active against tumors in mouse lymph nodes. Intralymphatic chemotherapy in mice with lymph nodes containing tumors was found to have a marked anti-tumor effect, compared with intravenous administration, and the addition of ultrasound combined with nano-/microbubbles enhanced the effect of the anti-cancer drug, but only when the drug was administered intralymphatically. Furthermore, decreases in the volumes and blood vessel densities of tumor-bearing lymph nodes are reliable measures of therapeutic effect, confirmed by histopathological evaluation. The main conclusion is that combining ultrasound with nano-/microbubbles and intralymphatic chemotherapy improves drug delivery to the lymphatic system and has a more potent anti-tumor effect.

Evaluation of reliability of ultrasonographic parameters in differentiating benign and metastatic cervical group of lymph nodes

The aim of the current study is to determine the efficacy of ultrasound in differentiating between benign and metastatic group of cervical lymph nodes. The study included forty-five subjects who were divided into three groups with 15 in each, by stratified random sampling method. Group 1 comprised fifteen patients without signs and symptoms of any infection and neoplasms in head and neck region (control group). Group 2 included fifteen patients with signs and symptoms of malignancy in head and neck region. Group 3 consisted of fifteen patients with signs and symptoms of odontogenic infections. "MY LAB-40" ultrasound machine with linear array transducer of 7.5 MHZ frequency was used for detecting cervical lymph nodes following Hajek's classification. The patients further underwent ultrasound guided FNAC under standard aseptic protocol and samples were subjected to cytopathological evaluation. Chi square analysis and one way ANOVA test were applied to obtain the results. We concluded that ultrasound and USG FNAC can be used accurately to assess the status of lymph nodes. The ultrasonographic features of lymph nodes with round shape, absence of hilar echo, sharp nodal borders, hyperechoic internal echogenicity, and presence of intranodal necrosis were highly suggestive of metastatic cervical lymph nodes.

Characterizing the major sonographic textural difference between metastatic and common benign lymph nodes using support vector machine with histopathologic correlation

Sonographic texture analysis can reflect histopathological components and their arrangement in metastatic and common benign lymph nodes. It is helpful in differentiation between metastatic and benign lymph node lesions for target selection during biopsy of multiple lymph nodes and the strategy of the management. Two ultrasound systems, 107 sonographic regions of interest (ROIs) of metastases and 174 sonographic ROIs of common benign lymph nodes, were recruited in the study. Thirteen texture features derived from co-occurrence matrix were used in characterization of above ROI ultrasound images. Support vector machine (SVM) was used as a classifier and a feature selector. The experimental results show that the entropy gains the best cross-validation accuracy of 94.66% and 87.73% in both ultrasound systems 1 and 2 for the classification of metastatic and benign lymph nodes disease. The accuracy can be further increased to 97.86% and 100% by the combination of the sum average in the study. There are significantly higher entropy and sum average values of the metastatic lymph nodes than of the benign lymph nodes, which are due to the heterogeneous compositions and arrangement of larger cancer cells, lymphocytes, and stroma in metastatic lymph nodes that contrast with simple inflammatory cells infiltration in common benign lymph nodes.

Computer-aided diagnosis of cervical lymph nodes on ultrasonography

A computerized system differentiating cervical lymph nodes on ultrasonography as malignant or benign was developed from a database of 210 cases. Ten quantitative features representing sonographic features of size, margin, nodal border, shape, medulla ratio, medulla distribution, echogenicity, echogeneity, vascular density, and vascular pattern, were respectively calculated under the node contour segmented by an improved snake model. A rough margin based support vector machine was trained to distinguish between malignant and benign nodes using the 10 computerized features. The receiver operating characteristic (ROC) analysis was used to evaluate the performance. The developed system showed the normalized area under the ROC curve (Az, which is used as a summarized measure of the accuracy, ranges from 0.5 to 1.0) of 0.892. Compared with the radiologist's performance of Az of 0.784 this system has the potential to be an aid to radiologists in the task of distinguishing between malignant and benign cervical nodes on ultrasonography.

Ultrasonographic feature selection and pattern classification for cervical lymph nodes using support vector machines

A rough margin based support vector machine (RMSVM) classifier was proposed to improve the accuracy of ultrasound diagnoses for cervical lymph nodes. Thirty-six features belonging to 10 kinds of ultrasonographic characteristics were extracted for each of 110 lymph nodes in ultrasonograms. Comparison studies were done for three classifiers--the classical support vector machine (SVM), the general regression neural network and the proposed RMSVM, with or without the feature selection by the recursive feature elimination (RFE) algorithm, respectively, based on SVMs and the mean square error discriminant. It was indicated by experimental results that all classifiers benefited from the feature selection. The best classification performance was obtained by the RMSVM using thirteen features selected by the RMSVM based RFE, which yielded the normalized area under the receiver operating characteristic curve (A(z)) of 0.859. Compared with the radiologist's performance of A(z) of 0.787, the developed computer-aided diagnosis algorithm has the potential to improve the diagnostic accuracy.

Ultrasonographic differentiation of benign from malignant neck lymphadenopathy in thyroid cancer

OBJECTIVE

The aim of this study was to determine whether ultrasonography itself was able to distinguish benign from malignant lymphadenopathy in patients with thyroid cancer.

METHODS

We evaluated lymph nodes in a group of patients with thyroid cancer. Nodes were detected and measured by ultrasonography, and their shape, echogenicity, size, and location were noted. Ultrasonographically guided fine-needle aspiration biopsy (FNAB) was performed, and smears were analyzed cytologically.

RESULTS

Ultrasonographically guided FNAB was performed in 578 neck nodes in a group of 631 patients with thyroid cancer. In most cases, metastases had a round shape and various echo structures, with a predomination of hypoechoic nodes without a hilum. There were statistical differences in size between metastatic and benign nodes in terms of maximum diameter, minimum diameter, and volume. Among these, minimum diameter and the shape of the nodes seemed to be the most reliable in suggesting malignancy. A round shape with a longitudinal/transverse ratio of less than 2 of hypoechoic nodes indicated the presence of metastases, and we then performed FNAB. The absence of an echogenic hilum and the presence of cystic portions and calcifications were significantly greater in malignancies than in benign lesions (P<.001). In most cases, metastatic nodules were situated in the lower third of the neck. Reactively enlarged nodes occurred more frequently in the upper part of the neck.

CONCLUSIONS

Ultrasonography itself cannot distinguish benign from malignant lesions, but an echographic appearance suggests malignancy and helps in the selection of the node to aspirate with ultrasonographically guided FNAB, which is crucial for a final diagnosis.

Dynamic assessment of antiangiogenic therapy by monitoring both tumoral vascularization and tissue degeneration

Tumor growth is dependent both on endothelial and tumor cells. The aim of this study was to investigate dynamically whether changes in tumor vasculature implicate tumor tissue degeneration during antiangiogenic therapies. In order to quantify intra-tumor vascularization and necrosis, we have used ultrasound technology. This study has identified essential parameters needed to quantify specifically and sensitively the number of microvessels and the extent of necrosis in xenografted human carcinomas during natural tumor evolution, using contrast-enhanced high-frequency ultrasonography with (HFCDUS) or without (HFUS) color Doppler. We showed that quantification of intra-tumor microvessels between HFCDUS and immunohistochemistry is correlated using an anti-CD31 antibody. Furthermore, quantification of tumor necrosis with HFUS was confirmed by histological examination of hematoxylin-eosin-saffranin-stained sections over the observation period. Subsequently, for the assessment of novel angiogenic inhibitors, HFCDUS and HFUS were used to elucidate the underlying dynamics linking vessel inhibition and tumor eradication. We describe a novel application for HFCDUS/HFUS that constitutes an effective, convenient, and non-invasive method for clinical assessment of angiogenic inhibitors. In conclusion, we showed that tumor cells abruptly became necrotic following an antivascular therapy, whereas untreated tumors were protected from degeneration by a significant blood supply.

Sonographic feature extraction of cervical lymph nodes and its relationship with segmentation methods

OBJECTIVE

The purpose of this study was to extract quantitative features for characterization of cervical lymph nodes on sonographic images and analyze the effect of a semiautomated segmentation method on the feature extraction.

METHODS

Contours of 186 cervical lymph nodes on sonographic images were separately delineated by 2 radiologists (R1 and R2) and a semiautomated segmentation method. For each node, 10 kinds of sonographic features (including 3 parameters of size; 12 parameters of margin; 4 parameters of nodal border; 10 parameters of echogeneity; and 1 parameter of shape, echogenicity, medulla ratio, medulla distribution, vascular density, and vascular pattern, respectively) were quantified by a computerized scheme based on the segmented contour. Correlations between the quantitative parameter and the radiologists' consensus grading were computed to assess the effectiveness of these parameters. Concerning the 14 best correlated parameters, the effect of the segmentation stage on the feature extraction was estimated by comparing the parameter values calculated under different segmentations in terms of relative ultimate measurement accuracy.

RESULTS

Good correlations between the computerized scheme and radiologists were seen in features of size, nodal border, shape, echogenicity, medulla ratio, medulla distribution, vascular density, and vascular pattern, whereas 10 of 12 parameters of margin features and 8 of 10 parameters of echogeneity features showed poor correlations. Paired t tests comparing the relative ultimate measurement accuracy computed using the R1-R2 and the R1-computer pairing showed no significant difference on 11 parameters for the 14 parameters analyzed.

CONCLUSIONS

The computerized feature parameters may be used as assisted indices for evaluating cervical lymphadenopathies from sonographic images. The semiautomated segmentation method satisfied the accuracy requirement of the feature extraction.

Traumatic neuroma and recurrent lymphadenopathy after neck dissection: comparison of radiologic features

PURPOSE

To retrospectively evaluate the ultrasonographic (US), computed tomographic (CT), and magnetic resonance (MR) imaging features that differentiate traumatic neuroma from recurrent lymphadenopathy after neck dissection.

MATERIALS AND METHODS

Imaging findings of 10 patients with a traumatic neuroma and 17 with recurrent lymphadenopathy were reviewed. US and CT were performed in all patients; MR imaging was performed in 16 patients. Findings analyzed at US included the diameter of the long and short axes, the short-axis-to-long-axis ratio, and the presence of a central hyperechoic area. Findings analyzed at CT were contiguity with common or internal carotid artery, lesion location in correlation with carotid artery, and the presence of a hyperattenuating rim. Findings analyzed at MR imaging included signal intensity on T1- and T2-weighted images, the presence of ring enhancement, and the presence of a hypointense rim on T2-weighted images.

RESULTS

Statistically significant differences were found between traumatic neuroma and recurrent lymphadenopathy in the short-axis-to-long-axis ratio (mean, 0.47 vs 0.72; P < .001), the short-axis diameter (mean, 5.7 vs 12.2 mm; P < .001), the presence of a central hyperechoic area (five of 10 patients [50%] vs one of 17 patients [6%]; P < .05), the frequency of contact with carotid artery (two of 10 patients [20%] vs 13 of 17 patients [76%]; P < .01), and the presence of a hypointense rim on T2-weighted MR images (three of six patients [50%] vs zero of 10 patients [0%]; P < .05). Findings in other parameters were not statistically significant.

CONCLUSION

Several imaging findings can differentiate traumatic neuroma from recurrent lymphadenopathy after neck dissection.

Evaluation of lymph node perfusion using continuous mode harmonic ultrasonography with a second-generation contrast agent

OBJECTIVE

To evaluate the contribution of continuous mode contrast-enhanced harmonic ultrasonography (CE-HUS) with a second-generation contrast agent to the characterization of superficial lymphadenopathies with respect to conventional ultrasonographic techniques (B-mode and power Doppler).

METHODS

Fifty-six lymph nodes from 45 patients were studied both by conventional techniques and by CE-HUS. The dimensions, intranodal architecture, margins, and location of vessels were evaluated. Subsequently, all the lymph nodes were examined by CE-HUS, and enhancement of echogenicity was evaluated. The diagnoses obtained by means of fine-needle aspiration cytologic examination, surgical biopsy, or both were compared with those obtained by ultrasonography.

RESULTS

Of the lymph nodes examined, 30 were benign and 26 were malignant (18 metastases and 8 non-Hodgkin lymphomas). The study using CE-HUS showed intense homogeneous enhancement in 28 of 30 reactive lymph nodes; perfusion defects in 17, of which 15 were neoplastic and 2 were inflammatory; intense but inhomogeneous speckled enhancement in the early arterial phase in 5 cases of lymphoma; and, last, scarce or absent intranodal enhancement in 4 metastases. The specificity, sensitivity, and accuracy of conventional techniques in differentiation between benign and malignant lymph nodes were 76%, 80%, and 78% versus 93%, 92%, and 92.8% for CE-HUS. The increase in correct diagnoses was significant (P = .05) when conventional ultrasonography was tested against CE-HUS.

CONCLUSIONS

Superficial lymph nodes can be characterized as being neoplastic or benign with a high degree of diagnostic accuracy on the basis of the perfusion characteristics evaluated by CE-HUS. This technique has been shown to afford a higher degree of accuracy than currently obtainable by any other ultrasonographic technique.

Ultrasonography of the medial iliac lymph nodes in the dog

Sixty-one medial iliac lymph nodes of 38 different dogs (eight with adenocarcinoma of the apocrine glands of the anal sac, 13 with multicentric lymphoma, six with multicentric lymphoma but in clinical remission, and 11 control dogs) were evaluated to assess the ability of ultrasound to identify and interrogate these lymph nodes across the different groups and to differentiate these groups using different sonographic parameters. Ultrasound proved to be useful to assess canine medial iliac lymph nodes. An increase in size or number of detected lymph nodes or finding rounder or heterogeneous lymph nodes could differentiate lymph nodes of dogs of the control group from lymph nodes of dogs with lymphoma or an adenocarcinoma of the apocrine glands of the anal sac. Subcategories of malignancy could not be differentiated. More studies need to be performed, both with patients with reactive lymph nodes and also focusing on other canine superficial lymph nodes, before generalizing the results of this study to other areas or diseases.

Diagnostic value of high-resolution B-mode and power-mode sonography in the follow-up of thyroid cancer

OBJECTIVE

Ultrasonography is an established diagnostic modality in the follow-up of thyroid cancer. Color flow Doppler has been proposed by some authors as an additional tool for differentiating benign from malignant cervical lesions in various types of head and neck cancer. Over the last few years, a new generation of high-resolution ultrasound platforms with the "power-mode" feature has become available, that also enables the imaging of small vessel blood flow. The objective of our study was to find ways of optimizing the differentiation of benign and malignant cervical tumors in thyroid cancer follow-up by means of sonography.

METHODS

Hundred and twelve cervical lesions in 90 patients with thyroid cancer were evaluated by high-end ultrasonography (Sonoline Elegra, Siemens) using a small-part transducer (7.5 L 40, Siemens). B-mode sonography was performed at a frequency of 8 MHz. The Solbiati index (SI= ratio of largest to smallest diameter), configuration, echogenicity, intranodular structures, and margins were assessed. Perinodular and intranodular blood flow was evaluated by color flow Doppler (PRF 1250 Hz for conventional color flow Doppler, 868 Hz for power-mode Doppler). Possible malignancy was validated by histology, cytology, scintigraphy, and follow-up. Thirty five lesions were benign (diameter 0.4-3.0 cm) and 77 were malignant (0.4-5.4 cm). The patients were randomized into a test group and a learning group to determine the diagnostic value of various ultrasound criteria by means of statistical analysis. In the learning group, decision rules based on the dichotomized criteria were developed using a logistic regression model. Sensitivity and specificity of these decision rules were then evaluated in the test group.

RESULTS

The presence of an echocomplex pattern or irregular hyperechoic small intranodular structures (criterion A) and the presence of an irregular diffuse intranodular blood flow (criterion B) are the best indicators of malignancy, whereas an SI >>2 is highly indicative of benign changes. Color flow Doppler is a useful addition to B-mode scanning for distinguishing benign and malignant neoplasms in the follow-up of thyroid cancer. Power-mode Doppler sonography significantly improves imaging of perinodular and intranodular blood flow when compared with conventional color flow Doppler.

CONCLUSION

We propose the following decision rules based on a combination of the criteria above: (A) and (B) fulfilled: malignant, if SI< or =4; (B) but not (A) fulfilled: malignant, if SI< or =3; (A) but not (B) fulfilled: malignant, if SI< or =2; neither (A) nor (B) fulfilled: malignant, if SI approximately equal to 1 (sensitivity: 90%; specificity: 82%; accuracy 88%).

Color duplex sonography in post-therapeutic neck evaluation

PURPOSE

Assessment of the clinical utility of color duplex sonography for post-therapeutic evaluation of the neck.

PATIENTS AND METHODS

Eighty neck sides were evaluated in a prospective nonrandomized study during the post-therapeutic course. Of these, 74 previously had undergone surgery, and 60 subsequently had additional radiotherapy. The diagnostic procedures applied were clinical examination, computed tomography, positron emission tomography, and color duplex sonography. The mean observation period was 18.6 months.

RESULTS

Seven of 80 (8.75%) neck sides exhibited recurrent disease, and 76.2% of the lymph nodes resected during the postoperative observation period showed malignancy. Color duplex echography could detect all lymph nodes. Sensitivity was 100%, and the specificity was 95.8%. The sensitivity and specificity of computed tomography and positron emission tomography were found to be 85.7% and 97.2%, respectively. Palpation had a sufficient specificity (95.8%) but only a very poor 14.2% sensitivity in the post-therapeutic neck.

CONCLUSION

In complex tissue alterations of the post-therapeutic neck, color duplex echography is a highly sensitive and easily applied diagnostic procedure for the detection of recurrent disease. It allows a high-resolution depiction of intranodal vascularization and adjacent structures. Problems may occur in the evaluation of vessels in nodes with a diameter of 6 millimeters and below. This may impair specificity in some cases.

Sonographic appearances of cervical lymph nodes: variations by age and sex

PURPOSE

The purpose of this study was to evaluate the age- and sex-related variations in the numbers and sonographic appearances of normal cervical lymph nodes.

METHODS

One hundred thirty-three healthy subjects (67 men and 66 women) underwent sonographic examinations of the neck, during which 1,299 lymph nodes were detected. The lymph nodes were assessed for their size, shape (short-to-long-axis ratio), and border sharpness, as well as for the presence of an echogenic hilum. The subjects were categorized by age (20-29, 30-39, 40-49, and > or = 50 years) and subcategorized by sex. The differences between the groups in the number of nodes and in their appearance were evaluated.

RESULTS

The mean number of nodes visualized on sonography was significantly higher (p < 0.05) in subjects aged 20-29 and 30-39 years than in subjects aged 40-49 and 50 years or older. The difference in the mean sizes of the cervical nodes between men and women was not statistically significant. The lymph nodes in subjects aged 20-29 and 30-39 years were commonly smaller than those in subjects aged 40-49 and 50 years or older, but the differences were not statistically significant. Neither the shape nor the border sharpness of the cervical lymph nodes varied significantly by age or sex. The incidence of an echogenic hilum within the lymph nodes increased significantly with age in both sexes (p < 0.05).

CONCLUSIONS

This study provides information about the sonographic appearances of and variations between normal cervical lymph nodes. The presence of an increased number of cervical lymph nodes and the absence of an echogenic hilum within the nodes may help to identify an abnormality more in older patients than in younger patients.

A probability prediction rule for malignant cervical lymphadenopathy using sonography

BACKGROUND

Our purpose was to weigh various sonographic parameters as predicting malignant cervical lymphadenopathy and build a reliable prediction rule.

METHODS

One hundred and eighty-nine cervical lymph node lesions from 125 consecutive patients were used for building the prediction model. Sonographic variables, including 15 morphologic features of B-mode, 5 vascular parameters of color Doppler mode, along with age and sex, were analyzed with multivariate logistic regression to evaluate the joint effect of a set of independent variables. A prediction rule for malignant lymphadenopathy was established, and prospective validation was assessed on a new group consisting of 100 lymph nodes from another 60 consecutive patients.

RESULTS

The association of heterogeneous content, long transverse diameter, pathologic vascular pattern, high vascular density, and older age provided the most robust prediction value. Scoring scale was designed as 1x (age) + 2x (vascularity index) + 3x (short axis) + 4x (vascular pattern) + 4x (internal echo) according to the parameter estimates of multivariate logistic regression analysis. Cut-off value of score >==10 as malignancy resulted in 89.2% sensitivity and 85.2% specificity. Prospective validation also showed satisfactory results (sensitivity, 82.9%; specificity, 86.2%).

CONCLUSIONS

By measuring only 4 sonographic parameters and age, this prediction rule could provide the physician a nonconfusing and reliable probability reference for managing cervical lymphadenopathy.

Sonographic detection and characterization of musculoskeletal and subcutaneous tissue abnormalities in sickle cell disease

Pain due to bone marrow infarction is common in homozygous sickle cell disease (SS disease). Musculoskeletal pathology may be responsible for persistent atypical symptoms. We have assessed the frequency and ultrasound appearances of soft tissue and joint abnormalities in SS disease. SS disease patients with atypical musculoskeletal symptoms were examined with ultrasound over a 2 year period. Ultrasound findings were correlated with those at surgery or percutaneous drainage. 31 episodes in 23 patients were referred for ultrasound. There were 36 abnormalities in 18 patients: abscess (n = 15), effusions (n = 5), soft tissue induration (n = 12), fat necrosis (n = 2), haematoma (n = 1) and reactive lymph node (n = 1). Five examinations were normal. Soft tissue abnormalities in patients over the age of 14 years were associated with intramuscular injections: fat necrosis (n = 1), haematoma (n = 1), indurated soft tissue (n = 1) and abscess (n = 7). Soft tissue abnormalities with no underlying cause were seen in seven patients: abscess (n = 4), indurated soft tissue (n = 2) and fat necrosis (n = 1). Ultrasound is the imaging modality of choice for delineating these abnormalities and allows percutaneous drainage.