Diagnostic reliability of ultrasonography in the preoperative staging of the N parameter in head and neck neoplasms

The demonstration of metastatic involvement of neck nodes is a crucial step in the staging of patients with head and neck tumors. Diagnostic accuracy, sensitivity, and specificity of US in the detection of lymph node metastases were evaluated in 48 patients with this type of malignancy. The patients subsequently underwent surgical node dissection. Comparison of US, clinical and histological data demonstrated US to have 93.7% diagnostic accuracy, 100% sensitivity, and 84% specificity--the corresponding clinical values being 81%, 79%, and 84%, respectively. Among several US parameters, a substantial role in differentiating metastatic from tumor-free lymph nodes was played by the evaluation of roundness index (RI), and by the demonstration of an intranodal hyperechoic stria: RI value was always higher than 2 in tumor-free nodes and the hyperechoic stria was always absent in metastatic nodes. US approach never failed to demonstrate metastatic nodes while clinics missed them in 6 patients. Thus, US appears the most valuable diagnostic tool for staging head and neck tumors; its diagnostic accuracy can be increased by the combination with US-guided aspiration biopsy.     

Differentiation between benign and metastatic cervical lymph nodes with ultrasound

Objective:

The differentiation between benign and metastatic lymph nodes with ultrasound (US) is based primarily on the evaluation of size, shape, margin and internal echo structure. The aim of this study is to determine whether these parameters are reliable indicators and to correlate internal echo structure and histopathological findings.

Materials and Methods:

Seventy-one nodes in 21 patients with pathologically proven oral squamous cell carcinoma were examined. The shortest diameter, the short/long diameter ratio (S/L ratio), margins and internal echo structure of the lymph node were evaluated by US. The internal echo structure was divided into six patterns: homogeneous hypoechoic, homogeneous hyperechoic, heterogeneous, eccentric hyperechoic, centric hyperechoic and anechoic pattern. In addition, internal echo structure was correlated with histopathological findings.

Results:

In 71.4% of the metastatic nodes, the shortest diameter was more than 10 mm and the S/L ratio was higher than that of benign nodes (average 0.71). Eleven (84.6%) of the 13 lymph nodes with irregular margins were metastatic. Heterogeneous and anechoic patterns were observed in metastatic nodes, whereas homogeneous hypoechoic and eccentric hyperechoic patterns were present in benign nodes. On ultrasonography with the corresponding histopathological findings, echogenic areas in the homogeneous hyperechoic, heterogeneous and centric hyperechoic patterns of metastatic nodes proved to be necrosis or fibrosis. Eccentric hyperechoic areas in benign nodes corresponded to the hilus and surrounding fatty tissue.

Conclusions:

The shortest diameter, S/L ratio, margin and internal echo structure were considered to be critical indicators to differentiate between benign and metastatic nodes. Secondary changes caused by tumour infiltration, necrosis, or fibrosis should be assessed when metastatic lymph nodes are differentiated from benign ones by internal echo structure.     

Ultrasonography in the diagnosis of post-pubertal epidemic parotitis and its complications

PURPOSE: To assess the yield of US in the study of salivary glands and other organs involved in post-pubertal mumps. PATIENTS AND METHODS: We examined 68 patients with serologically proven post-pubertal mumps (age range 14-34 years). All patients were symptomatic, with fever and salivary gland swelling in 25 cases, marked hyperamylasemia in 32, epigastric pain in 9, unilateral scrotal swelling and/or pain in 19 cases and acute bronchitis in 1 case. All patients underwent US of salivary glands, neck lymph nodes, abdomen and scrotum with 48 hours of admission. RESULTS: Salivary glands: Parotid and submandibular glands showed normal echotexture in all patients. The parotid glands also showed multiple hypeoechoic intraparenchymal lymph nodes which were, ovoid or rounded, with smooth margins and a central hyperechoic area, with diameter ranging 3-14 mm (mean 5.4). No intraparenchymal lymph nodes were observed in submandibular glands. Neck: All patients had enlarged submandibular lymph nodes (maximum diameter ranging 5-22 mm; mean 11 mm); swelling was always bilateral and it was symmetric in 19/68 patients (30%) versus asymmetric because of prevailing right side involvement (more numerous and bigger nodes) in the other 47/68 cases (70%). All lymph nodes showed a benign pattern, with an ovoid or elongated shape, homogeneous hypoechoic echotexture and a hyperechoic hilum. Abdomen: The pancreas showed normal volume and normal parenchymal echotexture in all patients. Liver and spleen were always normal. Testes: US showed mild unilateral hydrocele in 10 cases, hydrocele and unilateral swelling of epidymis in 5 cases, hydrocele and swelling of both epidymis and didymis with inhomogeneous echotexture because of intraparenchymal hypeoechoic areas in 2 cases. There were no US changes in 2 cases. CONCLUSIONS: US of the salivary glands shows a specific pattern in post-pubertal mumps which has never been reported for other salivary gland diseases. In contrast US signs in other organs are not specific.     

Analysis of cervical metastatic lymphadenopathy by ultrasonography

One hundred and eight cervical lymph nodes of 37 patients were evaluated by ultrasonography. All lymph nodes were examined histologically, and among them 63 lymph nodes were metastatic nodes. If submandibular, submental, mid and inferior internal jugular lymph nodes larger than 8 mm, and superior internal jugular lymph nodes larger than 9 mm had been regarded as metastasis, high sensitivity (92%) was demonstrated. All of 31 lymph nodes with unclear or irregular margin were metastatic. Eccentric hyperechoic area, which was considered to be the hilus of the lymph node, was observed in 20 nodes. Those were non-metastatic lymph nodes. Otherwise, all of 48 lymph nodes with inhomogeneous internal echoes or with central hyperechoic area and peripheral hypoechoic zone were metastatic. The in vivo and in vitro ultrasonograms of 25 lymph nodes were compared with histopathological findings. The metastatic region was not differentiated with the remaining area of the lymph node by ultrasonography. Necrosis showed an-, hypo-, iso-, or hyperechoic. Fibrosis showed iso- or hyperechoic. Inhomogeneous internal echoes were proved to be necrosis and fibrosis, and such a lymph node was metastatic. The eccentric hyperechoic area of the non-metastatic lymph node was attributed to fatty tissue. Ultrasonography was a useful examination for evaluating cervical lymph nodes.     

Usefulness of 201Tl SPECT in the predication of mediastinal lymph nodes metastasis in patients with non small cell lung carcinoma (NSCLC)

Predictivity of mediastinal lymph nodes metastasis of 201Tl SPECT were examined before operation in 113 patients with non-small cell lung cancer (69 adenocarcinoma, 31 squamous cell carcinoma, 10 large cell carcinoma, 2 bronchiolo-alveolar carcinoma, 1 neuroendocrine cell carcinoma). Patients were classified into two groups, with or without lymph nodes metastasis according to the pathological diagnosis. We calculated parameters of 201Tl SPECT early ratio, delayed ratio, retention index (RI) and maximal diameters. In addition, we calculated optimal cut-off value of RI to estimate the mediastinal lymph nodes metastasis. Mediastinal lymph nodes metastasis was confirmed pathologically in 62 patients. ER and DR did not show any statistical significance between two groups. Maximal diameters of primary tumor were also comparable between two groups. RI was significantly higher in mediastinal lymph node metastasis positive group compared to that in mediastinal lymph node metastasis negative group. The sensitivity (Sen), specificity (Spe), positive predictive value (PPV), negative predictive value (NPV) and accuracy (Acc) of 201Tl SPECT were 82.2%, 82.3%, 85.0%, 79.2% and 82.3%. These parameters were similar of higher than 72.6%, 82.4%, 83.3%, 71.2% and 77.0% of chest CT. The RI of 201Tl SPECT was useful tool for predicting lymph nodes metastasis in non-small cell lung cancer. The optimum cut-off value of RI in the prediction of mediastinal lymph nodes metastasis was 35%. We should take into account of upstaging in cases with higher RI (>35%).     

Distribution of intranodal vessels in differentiating benign from metastatic neck nodes

AIM: Recent studies report high accuracy of power Doppler sonography in the differentiation of benign from malignant cervical lymphadenopathy. This study was undertaken to identify which of the parameters used in Doppler sonography of cervical lymph nodes is accurate and readily applicable in routine clinical practice. MATERIALS AND METHODS: We reviewed the power Doppler ultrasound examinations of 50 patients with cytologically proven metastatic nodes from nasopharyngeal carcinoma and 50 patients with proven reactive lymphadenopathy. All the examinations had been performed by an experienced sonologist, and intranodal vascular distribution and resistance were evaluated during real-time ultrasound. Twenty metastatic nodes and 40 reactive nodes were less than 10 mm in maximum transverse diameter. The vascular patterns of lymph nodes were classified into three categories: (1) hilar; (2) capsular; (3) hilar and capsular. The resistive index (RI) and pulsatility index (PI) were measured by spectral Doppler. RESULTS: Although metastatic nodes (RI, 0.81 +/- 0.11; PI, 1.89 +/- 0.89) tended to have higher intranodal vascular resistance than reactive nodes (RI, 0.65 +/- 0.08; PI, 1.07 +/- 0.26), there was considerable overlap of the resistance parameters between benign and malignant nodes. Most of the metastatic nodes showed the presence of capsular vascularity (capsular, 16%; capsular and hilar, 78%), whereas the majority of the reactive nodes showed hilar vascularity (98%), and the difference was significant. CONCLUSION: The distribution of intranodal vascularity appears to be more useful than RI or PI in differentiating benign from malignant cervical lymphadenopathy. It is also easier to evaluate the distribution and the results are therefore readily applicable in routine clinical practice.     

Focal intracavitary masses recognized with the hyperechoic line sign at endovaginal US and characterized with hysterosonography.

In 42 women, endovaginal ultrasonography (US) was performed because of an abnormal central endometrial complex. Retrospective review of the endovaginal US scans and subsequently obtained hysterosonograms with histopathologic correlation showed a hyperechoic line surrounding the central endometrial complex in 25 patients, all of whom had focal intracavitary processes. Cystic spaces within the central endometrial complex in 17 of these patients reflected polyps; this finding was associated with a hyperechoic line in 15. At hysterosonography, all polyps (n = 29) had a narrow attachment to the endometrium. All five fibroids were broadly attached and had a rim of overlying endometrium. These focal abnormalities were easily distinguished from global endometrial processes amenable to a blind biopsy procedure. This initial experience showed that a hyperechoic line circumscribing the central endometrial complex at endovaginal US allows prediction of focal intracavitary disease, particularly when the line is associated with cystic spaces within the central endometrial complex. The presence of a hyperechoic line can be used to direct the patient to a visually guided hysteroscopic procedure rather than a potentially unsuccessful blind biopsy procedure. Alternatively, absence of a hyperechoic line can prompt management appropriately directed by hysterosonographic characterization of the uterine contents as focal or diffuse.     

Contrast-enhanced ultrasonography in peripheral lung consolidations: What’s its actual role?

AIM: To evaluate the diagnostic accuracy of contrast-enhanced ultrasonography (CEUS) in the differential diagnosis between neoplastic and non-neoplastic peripheral pleuro-pulmonary lesions. METHODS: One hundred patients with pleural or peripheral pulmonary lesions underwent thoracic CEUS. An 8 microliters/mL solution of sulfur hexafluoride microbubbles stabilized by a phospholipid shell (SonoVue^®) was used as US contrast agent. The clips were stored and independently reviewed by two readers, who recorded the following parameters: presence/absence of arterial enhancement, time to enhancement (TE), extent of enhancement (EE), pattern of enhancement (PE), presence/absence of wash-out, time to wash-out, and extent of wash-out. After the final diagnosis (based on histopathologic findings or follow-up of at least 15 mo) was reached, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR) of each CEUS parameter in the differential diagnosis between neoplastic and non-neoplastic lesions were calculated. Furthermore, an arbitrary score based on the ratio between the PPVs of each CEUS parameter was calculated, to evaluate if some relationship could exist between overall CEUS behaviour and neoplastic or non-neoplastic nature of the lesions. RESULTS: Five patients were lost at follow-up before a conclusive diagnosis was reached, 53 lesions resulted neoplastic and 42 non-neoplastic. Enhancement in the arterial phase was observed in 53/53 neoplastic lesions and 30/42 non-neoplastic lesions. On the whole, 40/42 non-neoplastic lesions showed absence of enhancement or early enhancement (95.2%) vs 3/53 neoplastic lesions (5.7%). EE was marked in 29/53 (54.7%) neoplastic lesions and 25/30 (83.3%) non-neoplastic lesions, moderate in 24/53 (45.5%) and 5/30 (16.7%), respectively. PE was homogeneous in 6/53 (11.3%) neoplastic lesions and 18/30 (60%) non-neoplastic lesions, inhomogeneous in 47/53 (88.7%) and 12/30 (40%), respectively. 19/30 (63.3%) non-neoplastic lesions enhancing in the arterial phase had no wash-out in the venous phase, 11/30 (36.7%) had late and mild wash-out. Wash-out was early in 26/53 (49%) neoplastic lesions, late in 26/53 (49%), absent in 1 (2%); marked in 16/53 (30.2%), and moderate in 36/53 (67.9%). The delayed enhancement in the arterial phase showed a sensitivity of 94.32%, specificity of 95.2%, PPV of 96.2%, NPV of 93%, PLR of 19.81, and NLR of 0.06 in identifying the neoplastic lesions. All other parameters individually considered showed unsatisfactory values of sensitivity, or specificity, or both, in differentiating neoplastic from non-neoplastic lesions. The median of the overall arbitrary score was 3 (range 0-14) in non-neoplastic lesions, and 16.5 (range 7.0-17.5) in neoplastic lesions (P < 0.001). The correlation between the diagnosis of neoplastic vs non-neoplastic lesion and the score value was statistically significant (r = 0.858, P < 0.001). Based on the score distribution, a cut-off of 7.5 enabled to reach a sensitivity of 98.1%, specificity of 95.1%, PPV 96.3%, NPV 97.5%, PVR 20.1 and NVR 0.02 in differentiating neoplastic from non-neoplastic lesions. CONCLUSION: CEUS could be useful in the diagnostic workup of pleuropulmonary lesions. A delayed TE or a score ≥ 7.5 suggest the neoplastic nature of a lesion.     

Role of strain elastosonography,B mode and color duplex ultrasonography in differentiation between benign and malignant axillary lymph nodes

Aim and objectives: to evaluate diagnostic accuracy of combined gray scale, color Doppler and strain elastosonography in differentiation between benign and malignant axillary lymph nodes. Methodology: 50 patients with 60 enlarged axillary lymph nodes (20 male and 30 female), their ages ranged from 25 to 66?years with a mean of 37.4?years. Grey scale, color-power Doppler US and strain elastography were performed for all patient. Results: absent echogenic hilum, LS/TS ratio less than 2, transverse diameter more than 7, cortical thickness more than 3?mm, high RI were the most US patterns predictive of malignancy. Suspicious lymph nodes by elastography (Scores 3 and 4) were found in 45 (75%) lymph nodes with sensitivity 88.89%, specificity 66.67%; accuracy 83.33%. The best strain ratio cutoff of 2.3 with sensitivity 87.89% and specificity 65.67%; accuracy 82.3%. Rounded shaped, loss or compressed nodal hilum and suspicious elastography score (3 & 4) were the most predictive for malignancy with sensitivity 86.67% and specificity 93.33%; accuracy 88.33%. Conclusion: combined gray scale, color Doppler US and elastography improve diagnostic accuracy of conventional ultrasound alone in differentiation between benign and malignant axillary lymph nodes with sensitivity 86.67%, and specificity 93.33%; accuracy 88.33%.     

Role of echography in the differential diagnosis of accessory lobulations and small capsular traumatic fissures of the spleen]

Emergency US in patients with abdominal trauma has become a routine diagnostic exam thanks to both its high reliability and its short acquisition time. US allows the overall evaluation of the patient, relative to both the localization of even very small fluid collections and the evaluation of traumatic changes in parenchymatous abdominal organs, especially the spleen which is often injured. Twelve patients were selected of all the cases submitted to emergency abdominal US between February 1989 and March 1992. All the cases with evident traumatic lesions of the spleen were excluded. In 10 cases US demonstrated interrupted splenic parenchyma, which was highlighted by intraperitoneal fluid collections; the interruption of splenic parenchyma is also evidenced by a thin hyperechoic capsular line with no changes in the echopattern of deep parenchyma. Surgery in 6 patients--4 of them as an emergency for hemoperitoneum and 2 operated subsequently--and US monitoring in the extant cases confirmed the diagnosis of simple accessory splenic lobulations. On the contrary, in 2 patients hospitalized in emergency, US showed no evident traumatic splenic alterations but only interruption of the hyperechoic capsular line with low hypoechogenicity in the splenic parenchyma below and a small fluid collection next to the lower splenic pole. Splenectomy confirmed a limited marginal tear of about 1.5 cm. The misdiagnosis of traumatic tears can be avoided if congenital splenic lobulation--evidenced by hemoperitoneum--is considered. US must also be employed to demonstrate minimal alterations in the hyperechoic capsular line of the spleen, in order to point out possible small tears and, if necessary, to suggest the need for clinical monitoring.     

Lymphangioleiomyomatosis: abdominopelvic CT and US findings

PURPOSE: To describe the abdominal computed tomographic (CT) and ultrasonographic (US) findings in patients with thoracic lymphangioleiomyomatosis (LAM) and to relate the prevalence of the findings to the severity of pulmonary disease. MATERIALS AND METHODS: Eighty patients with LAM underwent chest and abdominopelvic CT and abdominopelvic US. The images were reviewed prospectively by one radiologist, and the abdominal findings were recorded and correlated with the severity of pulmonary disease at thin-section CT. RESULTS: Sixty-one (76%) of 80 patients had positive abdominal findings. The most common abdominal findings included renal angiomyolipoma (AML) in 43 patients (54%), enlarged abdominal lymph nodes in 31 (39%), and lymphangiomyoma in 13 (16%). Less common findings included ascites in eight (10%), dilatation of the thoracic duct in seven (9%), and hepatic AML in three (4%). A significant correlation (P =.02) was observed between enlarged abdominal lymph nodes and increased severity of lung disease. CONCLUSION: There are characteristic abdominal findings in patients with LAM that, in conjunction with the classic thin-section CT finding of pulmonary cysts, are useful in establishing this diagnosis.     

Role of sonography in the evaluation of parotid gland in HIV+ children undergone highly active antiretroviral therapy (HAART)]

PURPOSE: To evaluate the role of sonography (US) in the evaluation of parotid gland alterations in HIV+ children, in order to show their presence, severity, specificity, relationship with clinical and laboratory data and sensitivity to new drugs. MATERIAL AND METHODS. From June 2000 to December 2000 twenty-two consecutive HIV+ children (12 males and 10 females, mean age 9.7) undergoing HAART were prospectively examined with US. A multi-frequency linear probe (7.5-10 MHz) was used for the examination. The glands were assessed for alterations in gland volume and vasculature, hypoechoic foci, hyperechoic striae, lympho-epithelial cysts and solid nodules and the enlargement of intraparotid and adjacent lympho nodes. The US findings on HIV+ patients were compared with the patients'clinical and laboratory data and with US exams performed on HIV- children. Finally, we made a comparison with US exams performed on the same patients before HAART. RESULTS. In HIV+ children the most frequent US findings were hypoechoic foci (68.2% of patients), hyperechoic striae (68.2%) and the enlargement of intraparotid and adjacent lympho nodes (86.3% and 95.4%, respectively). No relationship between US outline and clinical and laboratory data was found. In the control group (HIV-negative children) hypoechoic foci and hyperechoic striae were rare (4.7% and 14.3%, respectively), while the enlargement of intraparotid and adjacent lympho nodes was very common (76.2% and 100%, respectively). The comparison with US exams performed on the same patients before HAART showed an improvement in 59.1% of patients, no improvement in 13.6% and a worsening in 13.6% (3 patients were lost to follow-up). DISCUSSION AND CONCLUSIONS. US is useful in the study of parotid gland alterations in HIV+ children. The most frequent specific US findings were hypoechoic foci and hyperechoic striae, whereas the enlargement of intraparotid and adjacent lympho nodes was frequent but completely aspecific. The analysis of results did not show any relationship between the US findings and clinical and laboratory data. HAART can be correlated to an improvement and/or a stabilization of the US pattern in most patients.     

Ultrasonic diagnosis of the central hyperechogenic area in lymph nodes. A sign of benign lymphadenopathy

When identifying superficial lymphadenopathies by means of echotomography, the only accepted criterium of evaluation is still dimension. Only lymph nodes with a diameter longer than 0.5 cm are considered as potentially pathological, irrespective of their morphological characteristics. In the past two years an echotomographic study of the surface regions was carried out on 300 patients. Some suffered from unspecific solitary lymphadenopathies; most of the others were affected by stationary neoplasias, mainly situated in the cervical region. In many cases it has been possible to correlate the echotomographic and the histological results. Sixty-nine out of the 300 examined patients had lymph nodes with a central hyperechogenic area. Histology showed these lymph nodes to be the site of reactive hyperplasia. This characteristic has never been found in neoplastic lymph nodes. It has been hypothesized that this spot corresponds to the hilus of the lymph node and that, through its identification, it may be possible to distinguish benign from neoplastic lymph nodes.     

The use of unenhanced Doppler sonography in the evaluation of solid breast lesions

OBJECTIVE: The objectives of our study were to investigate differences in Doppler sonography features between benign and malignant breast lesions and between malignant lesions with different prognostic factors and to propose diagnostic criteria for Doppler sonography of breast lesions. SUBJECTS AND METHODS: We performed power and duplex Doppler sonography examinations in 826 breast lesions scheduled for sonographically guided core needle biopsy. Lesion vascularity, pulsatility index (PI), and resistive index (RI) of the vessels detected were analyzed and correlated with histologic results. RESULTS: Color flow was more frequently seen in malignant (237/348 lesions, 68%) than in benign (171/478, 36%) lesions (p < 0.001). However, sensitivity, specificity, and positive and negative predictive values for this sign were low (68%, 64%, 58%, and 73%, respectively). The RI and PI values were significantly higher (p < 0.001) in cancers. Although an overlap in these values between benign and malignant lesions was observed, all but one nodule with an RI of greater than 0.99 (those with null or inverted diastolic flow) or a PI of greater than 4 were malignant. No significant relationship was found between PI, RI, or flow visualization on power Doppler sonography and tumor grade or lymph node involvement in cancers. CONCLUSION: Flow visualization on power Doppler sonography indicates a higher possibility of malignancy but is not useful as the main sign for malignancy. However, any lesion with a vessel that has an RI value greater than 0.99 or a PI value greater than 4 within it must be considered as probably malignant regardless of any other sonography sign present. Doppler findings are not useful to predict tumor grade or lymph node involvement.     

甲状腺癌颈部淋巴结转移的超声表现及对临床治疗的意义

目的:分析甲状腺癌颈部淋巴结转移的超声表现,探讨转移淋巴结的声像图特征、分布及对临床治疗的指导意义。方法:回顾性分析50例甲状腺癌患者126枚颈部转移淋巴结的超声表现及分布,所有病灶均经手术或超声引导下穿刺活检证实。分析转移淋巴结的长短径比值、边界、皮质厚度、淋巴门、内部囊性变、内部钙化、Adler血流分级、峰值流速(peak systolic velocity,PSV)、RI,并与40枚反应增生性淋巴结对比。结果:转移淋巴结长短径比值较小、边界欠清、皮质增厚、淋巴门高回声消失、内部可见囊性变及钙化、Adler血流分级及PSV均较高,与反应增生性淋巴结相比差异有统计学意义。结论:甲状腺癌颈部淋巴结转移具有特征性超声表现,其准确诊断及定位有助于指导患者的治疗。     

Cyclic endometrial changes: US assessment with histologic correlation

The ultrasonographic (US) appearance of the endometrium was evaluated in 80 patients, and the US diagnosis of endometrial stage was compared with that from same-day endometrial biopsy specimens. The US signs of proliferative endometrium included triple-line sign, hypoechoic function layer, and minimal or absent posterior acoustic enhancement. The signs of secretory endometrium included absent triple-line sign, hyperechoic functional layer, and strong posterior acoustic enhancement. When all of these US signs were clearly depicted in combination, the accuracy of diagnosis was 93% (30 patients). The accuracy of diagnosis for all patients in the study was 76% (73 patients). The relative distributions of each US sign in proliferative and secretory endometrium were compared. Despite complicating extrinsic factors such as uterine leiomyomas and intrinsic factors such as the transition period between endometrial phases, US staging of the endometrium is a useful diagnostic technique that allows serial examinations of the endometrium.     

Sentinel node detection using contrast-enhanced power Doppler ultrasound lymphography

RATIONALE AND OBJECTIVES: To establish the feasibility of using contrast-enhanced interstitial ultrasound (US) lymphography as an alternative to current sentinel node detection methods. METHODS: Aqueous US contrast microbubble suspensions of varying diameter were evaluated in vitro to characterize response to insonation. Contrast media were then injected subcutaneously into the distal extremities of 11 normal dogs to target the cervical and popliteal lymph nodes (nodes, n = 40). First-order (sentinel) lymph nodes and second-order sublumbar nodes were imaged intermittently from 0 to at least 120 minutes following contrast injection using continuous power Doppler mode. Lymphoscintigraphy studies were performed on 4 dogs to verify lymphatic drainage patterns and sentinel lymph nodes. RESULTS: Contrast enhancement occurred in 34/40 (85%) sentinel nodes overall and in 30/32 (94%) nodes when submicron or near-micron diameter bubble formulations were used. In many instances, enhancement persisted throughout the imaging period. Contrast response was most pronounced using a high mechanical index and tissue artifact was reduced or eliminated when using a high pulse repetition frequency. CONCLUSIONS: Contrast-enhanced interstitial US lymphography could serve as an alternative to current sentinel node detection methods. Preliminary findings suggest that submicron or near-micron-diameter bubbles may be suitable for lymphatic imaging applications.     

Intracapsular osteoid osteoma of the proximal femur: findings on plain film and CT

The sonographic evaluation of lymph nodes is based primarily on evaluation of their shape and size. Recently, however, the availability of high-frequency transducers has made consideration of internal structure possible. An important objective is to determine whether node enlargement is due to inflammatory or neoplastic processes. To determine the accuracy of sonography for this purpose, we obtained in vitro sonograms of 53 enlarged lymph nodes excised from 41 patients during surgery for neoplastic or nonneoplastic disease. The sonograms were obtained with 7.5- and 10-MHz transducers. They were interpreted by a radiologist who was unaware of the clinical diagnosis. The nodes were subsequently processed for anatomohistologic study; findings were compared side by side. In 26 of the 53 nodes, sonograms showed an identifiable central echogenic line, which on histologic specimen corresponded to the internal part of the medulla where the lymphatic sinuses converge. All these nodes were benign. Two other nodes had an echogenic internal structure not resembling the normal hilum; in one case this was caused by metastatic disease and in the other by fibrosis. Sonograms of the remaining 25 nodes showed no detectable hilar structure; 21 were involved by a tumor and four had diffuse fatty replacement. Our results suggest that the sonographic finding of a central echogenic line is a valid criterion of benignity. Absence of this finding may be due to factors other than neoplastic disease, such as fatty replacement.     

胰腺结核的超声声像图表现

目的：提高对胰腺结核术前的诊断率。材料和方法：将经手术和病理证实的3例胰腺结核和10例胰腺癌病例的声像图进行对比研究。采用ESAOTE AU—5超声诊断仪，频率3．5MHz探头。结果：3例胰腺结核临床均误诊为胰腺癌，CT诊断不能肯定，但在超声声像图上显示有一定特征。3例胰腺结核声像图表现为多病灶、边界清楚、有线条状强光带包绕的低回声，但无声衰减，同时伴腹腔后腹膜淋巴结肿大。结论：超声在胰腺结核的诊断上有一定的临床应用价值。     

Brain death in infants: evaluation with Doppler US

In a preliminary study, nine infants with a clinically determined diagnosis of brain death were examined with duplex pulsed Doppler ultrasonography (US) through the anterior fontanelle. Flow velocity measurements were made in the intracranial internal carotid artery and anterior cerebral artery. Resistive index (RI) was calculated in each patient and used as an indicator of diastolic flow. Eight of nine infants showed markedly elevated RI (100%-191%) with reversal of diastolic flow. One infant had low RI (42%-58%) with preserved systolic and diastolic flow until death. The authors believe that the elevation of RI with diastolic flow reversal seen in these patients is a reflection of increased intracranial pressure and is a sign of poor prognosis when present on serial examinations. Cranial duplex pulsed Doppler US is a useful, noninvasive tool in the diagnosis of brain death in infants but must be carefully correlated with clinical examination and other diagnostic tests.