Use of intravenous contrast material in transcranial sonography

RATIONALE AND OBJECTIVES: The appearance of the intracranial vasculature was compared on power and color Doppler ultrasound (US) scans obtained with and without a microbubble contrast agent. MATERIALS AND METHODS: Nine patients (three men, six women) aged 42-70 years (mean age, 53 years) participated in the study. Seven patients underwent both color Doppler US and power Doppler US before and after intravenous administration of contrast agent, and two underwent only color Doppler US. All patients had previously undergone cerebral angiography. RESULTS: Before contrast material was administered, power Doppler US was more sensitive than color Doppler US in the detection of intracranial vessels (P < .05); neither technique depicted the entire circle of Willis in eight of nine patients. Postcontrast power Doppler US depicted more vascular segments than postcontrast color Doppler US (P < .01) or precontrast power Doppler US (P < .01). Use of intravenous contrast material enabled the entire circle of Willis to be evaluated from a single temporal bone acoustic window with both power Doppler US and color Doppler US in all patients. Contrast-enhanced power Doppler US depicted vessels not shown by enhanced color Doppler US. CONCLUSION: Contrast-enhanced power Doppler US depicted more vessels, better demonstrated specific vascular segments, and provided better vascular definition of the intracranial vasculature than contrast-enhanced color Doppler US or unenhanced power Doppler US.     

Color Doppler ultrasound pulsatile flow signals of thoracic lesions: comparison of lung cancers and benign lesions

Color Doppler ultrasound (US) was performed in 153 patients (including 102 with lung cancer and 51 with benign lesions) to assess pulsatile flow signals in thoracic lesions. The values of resistive index (RI) and pulsatility index (PI) of color Doppler US pulsatile flow signals in lung cancers and benign lesions were measured, analyzed, and compared. In the enrolled 153 patients with thoracic lesions, 61 lung cancers and 34 benign lesions had detectable color Doppler US pulsatile flow signals, and lung cancers had lower RI and PI values than benign lesions (RI: 0.70+/-0.03 vs. 0.79+/-0.04, p < 0.05; PI: 1.61+/-0.15 vs. 2.44+/-0.25, p < 0.005). However, overlapping RI and PI values in lung cancers and benign lesions somewhat limited color Doppler US pulsatile flow signals to differentiate lung cancers from benign lesions. Further analysis of RI and PI values in subgroups of lung cancers [squamous cell carcinoma (SCC, n = 34), adenocarcinoma (AC, n = 18), and small-cell lung cancer (SCLC, n = 6)] and benign lesions [cavitary benign lesions (CBL, n = 8), and noncavitary benign lesions (NCBL, n = 26)] revealed that all different cell types of lung cancers (SCC, AC, and SCLC), indeed, had lower RI and PI values than NCBL (for RI, all p < 0.01; for PI, all p< or =0.001). Moreover, the mean RI and PI values showed a significant incremental decrease from NCBL (mean RI, PI = 0.88, 2.94) toward SCC and AC (for SCC, mean RI, PI = 0.71, 1.68; for AC, mean RI, PI = 0.68, 1.67) and, finally, to SCLC (mean RI, PI = 0.62, 1.05). In contrast, CBL had relatively lower RI and PI values than AC and SCLC (for CBL, mean RI, PI = 0.53, 0.80; both p > 0.05 for RI and PI), and even a significant difference from SCC (p < 0.05 for RI and PI). We conclude that color Doppler US pulsatile flow signal is somewhat limited to differentiate lung cancers from benign lesions, but provides a noninvasive in vivo model to assess the neovascularity intensity of lung cancers.     

Liver vascular transit time analyzed with dynamic hepatic venography with bolus injections of an US contrast agent: early experience in seven patients with metastases

Spectral Doppler intensitometry to study transit of a bolus of an ultrasonographic (US) contrast agent in the hepatic veins was performed in seven patients suspected of having liver metastases and seven control subjects. All control subjects had a late response (rise time, > 25 seconds; time to peak intensity, > 45 seconds), whereas six of seven patients had an early response (rise time, < 25 seconds; time to peak intensity, < 45 seconds) (P < .01).     

Vascular patterns of gestational trophoblastic tumors by color Doppler ultrasound

BACKGROUND: Destruction of uterine vasculature is a common phenomenon in gestational trophoblastic tumors. The authors categorized such uterine vasculature by color Doppler ultrasound and studied its clinical significance. METHODS: Color Doppler ultrasound was performed in 28 patients with gestational trophoblastic tumors. The vascular morphologic manifestations were recorded, and the peak systolic velocity and resistance index of uterine artery were calculated. Serum beta-human chorionic gonadotropin (hCG) levels were measured periodically to monitor chemotherapy response. Seventeen uneventful postmole uteri were used as controls. Two-tailed Student's t-test and Fisher's exact test were used for statistical analysis. RESULTS: The gestational trophoblastic tumors were categorized as diffuse type (N = 7), lacunar type (N = 16), and compact type (n = 5) according to their vascular patterns. The mean serum beta-hCG level at diagnosis in diffuse type lesions (6608 +/- 6320 mIU/mL) was significantly lower than in the lacunar type (40462 +/- 39735 mIU/mL; P = 0.04) and compact type (212114 +/- 205126 mIU/mL; P = 0.02), whereas the level in compact type lesions was significantly higher than in the lacunar type (P = 0.003). Lacunar type lesions exhibited a significantly lower uterine artery resistance index (0.51 +/- 0.13) than diffuse type (0.66 +/- 0.10; P = 0.03) or compact type lesions (0.70 +/- 0.06; P = 0.02). All lesions exhibited significantly higher peak systolic velocity than control subjects (P < 0.001); however, no significant difference was observed among them. Brief courses (< 5 cycles) of chemotherapy cured more diffuse type (6 of 7) than lacunar type (3 of 15, P = 0.006) or compact type lesions (0 of 5, P = 0.008). Histopathologic diagnosis was available for 11 lesions. They were invasive mole in seven lacunar type lesions and choriocarcinoma in four compact type lesions. CONCLUSION: Vascular morphologic patterns of gestational trophoblastic tumors by color Doppler ultrasound correlated well with beta-hCG levels, uterine hemodynamics, chemotherapy response, and possibly the histopathologic diagnosis.     

Novel variants of voltage-operated calcium channel alpha 1-subunit transcripts in a rat liver-derived cell line: deletion in the IVS4 voltage sensing region

To assess the usefulness of adenosine triphosphate (ATP) as an alternative agent for functional determination of coronary circulation in children and to reveal the dose-response kinetics of intracoronary ATP, systemic hemodynamics and spectral coronary flow velocity dynamics using Doppler guide wire were measured during hyperemic responses to an intracoronary bolus injection of ATP (0.01 microgram/kg, 0.1 microgram/kg and 1.0 microgram/kg) in consecutive 40 Kawasaki disease patients (age: 8.4 +/- 5.1 years, 30 boys and 10 girls) without angiographic coronary lesions. ATP did not produce any significant change in heart rate, systolic blood pressure and mean blood pressure, but mildly decreased diastolic blood pressure. The coronary flow reserve (CFR) calculated as a ratio of hyperemic to basal averaged peak velocity (APV) for ATP was 2.05 +/- 0.31, 2.26 +/- 0.38 and 2.50 +/- 0.51 in LAD, and 2.24 +/- 0.28, 2.44 +/- 0.41 and 2.60 +/- 0.47 in RCA, respectively, for each of the three doses. There was no statistical significance between the mean values of CFR in LAD with ATP (1.0 microgram/kg: 2.39 +/- 0.16) and papaverine (0.15 microgram/kg: 2.43 +/- 0.16) in six patients without angiographic coronary lesions. The maximal coronary hyperemia was reached rapidly after intracoronary bolus injection of ATP in all doses (10, 10-15 and 15-20 seconds in both LAD and RCA, respectively, for each of the three doses). The time required for APV to return to basal levels (< T10%) increased with the dose of ATP (30, 55 and 110 seconds in LAD and 35, 45 and 100 seconds in RCA, respectively, for each of the three doses). Three patients (3/40: 7.5%) developed transient (< 5 seconds) asymptomatic second degree atrioventricular block, but no patient had clinically significant arrhythmias. The change ratio in QTc interval after ATP injection was 1.96 +/- 1.87% (not significant). In addition, an intracoronary injection of ATP did not increase the absolute angiographic coronary luminal diameter. This study indicates that ATP is a safe alternative agent for pharmacological induction of coronary hyperemia for evaluation of coronary stenotic lesions and for the study of coronary circulation and coronary flow reserve in children.     

Flow injection immunoanalysis based on a magnetoimmunosensor system

To establish criteria for the differentiation of benign and malignant tumors of the parotid gland using color Doppler sonography (CDS) and pulsed Doppler sonography (PDS) we examined 37 patients with parotid tumors by gray-scale ultrasound, CDS, and PDS. Tumor vascularization displayed by CDS was graded subjectively on a 4-point scale (0 = no vascularization, 3 = high vascularization). From the Doppler spectrum, the highest systolic peak flow velocity, the resistive index (RI), and the pulsatility index (PI) were calculated. There were 11 malignant and 26 benign tumors. Tumor vascularization by CDS was grade 0 or 1 in 88.5% of benign lesions, whereas it was grade 2 or 3 in 82% of malignant lesions (P < 0.0001). The highest systolic peak flow velocity was statistically significantly higher in malignant lesions than in benign lesions. Using a threshold systolic peak flow velocity of 25 cm/s, sensitivity was 72% and specificity was 88% for the detection of a malignant tumor. Evaluation of tumor vascularization by CDS and PDS cannot differentiate between benign and malignant parotid tumors with certainty. However, high vascularization and high systolic peak flow velocity in tumor vessels should raise the suspicion of malignancy, even if tumor morphology on gray-scale sonography indicates a benign lesion.     

Surgical management of thoracic manifestations in human immunodeficiency virus-positive patients: indications and results

PURPOSE: To quantify color Doppler (CD) signals reflected by breast lesions to improve differential diagnosis and serial comparisons. MATERIALS AND METHODS: Frame-grabbed color-capture scans were remapped to original velocities on a pixel-by-pixel basis for statistical analysis. Total CD area and its percentage, peak and mean velocities, standard deviation of velocity, and integral CD velocity and its percentage were calculated. These indexes were applied to scans of 44 cancers, 16 fibroadenomas, and 14 benign breast changes in 74 patients. RESULTS: With the region of interest confined to the lesion and a 5-mm margin, no CD signals were reflected by the benign breast changes. All carcinomas and 12 fibroadenomas (those that were vascular) reflected CD signals, and, except for mean and peak velocity, all scores for cancers were significantly higher than for fibroadenomas (P < .0001). Integral CD velocity was the best discriminator, with no overlap between carcinomas (range, 1,128-50,228 cm3/sec) and fibroadenomas (range, 0-1,027 cm3/sec). CONCLUSION: Automatic CD quantification improved differential diagnosis of breast masses.     

D-galactose-based signal-enhanced color Doppler sonography of breast tumors and tumorlike lesions

RATIONALE AND OBJECTIVES: This study sought to evaluate prospectively the diagnostic potential of unenhanced and enhanced color Doppler and power Doppler for the differentiation of tumors and tumorlike lesions of the breast. METHODS: Ninety-two patients with 110 tumors or tumorlike lesions of the breast were investigated by unenhanced and enhanced color and power Doppler ultrasound. The sonomorphologic aspects of vascularization were analyzed. In addition, maximal systolic frequency shift, resistance, and pulsatility indices were determined. RESULTS: In 15 (24%) of 63 primary carcinomas, 15 (68%) of 22 fibroadenomas, and all (100%) of 14 postoperative lesions, the sonomorphologic analysis for the differential diagnosis of breast tumors was improved after contrast enhancement in color Doppler mode. In comparing unenhanced color Doppler to power Doppler, the latter was found to be slightly superior (sensitivity, 60% vs. 67%; specificity, 39% vs. 45%, respectively); after enhancement, both modes were equivalent (sensitivity, 100% vs. 100%; specificity, 95% vs. 95%, respectively). Signal enhancement resulted in a significant improvement in sensitivity and specificity (P < 0.01). Typical signs of malignancy were irregular vessel calibers, serpiginous courses, penetration of the tumor's margin, and irregular reticular vascularization. The quantitative parameters proved not to be helpful for the differential diagnosis of breast tumors. CONCLUSIONS: By improved analysis of the vascularization pattern, d-galactose-enhanced color Doppler sonography was found to provide more reliable differential diagnostic information than unenhanced Doppler ultrasound in tumors and tumorlike lesions of the breast.     

Does solitary plasmacytoma still exist? Value of MRI of the spine

In order to differentiate benign from malignant pulmonary masses by means of observing blood flow signal, with coloured Doppler sonography, the authors examined 67 in-patients who had been found having masses in the lungs by X-ray or CT. For comparison 43 benign cases showing blood signals in the lung was also examined. The results showed that the blood flow signals of all lung cancers were of relatively low blood flow resistance or arteriovenous shunting, while those of benign lesions were of high blood flow resistance. The pulsatility index in lung cancer was 1.02 +/- 0.30, the restance index was 0.52 +/- 0.13, the peak systolic velocity was 0.19 +/- 0.11 m/s, the end diastolic velocity was 0.06 +/- 0.02 m/s. The pulsatility index in benign pulmonary lesions was 1.53 +/- 0.30, the resitance index was 0.86 +/- 0.05, the peak systolic velocity was 0.28 +/- 0.05 m/s and the end diastolic velocity was 0.04 +/- 0.01 m/s. There were significant differences between the benign and malignant pulmonary lesions in the four indices (P < 0.01) by t test and t' test. Lower pulsatility index, lower resistance index, lower peak systolic velocity and higher end diastolic velocity were characteristics of malignancy.     

Disruption of p53 function in immortalized human cells does not affect survival or apoptosis after taxol or vincristine treatment

OBJECTIVE: We assessed the feasibility of contrast-enhanced color Doppler, power Doppler, and spectral duplex sonography for visualization and quantification of flow through transjugular intrahepatic portosystemic shunts (TIPS) in patients in whom the baseline sonographic evaluation was unsatisfactory. SUBJECTS AND METHODS: Thirty-three patients underwent color Doppler, power Doppler, and spectral duplex sonography after TIPS insertion or before TIPS revision (mean time interval +/- SD, 1 +/- 1 day). All sonograms were obtained before and after patients received echo-enhancing contrast material. Sonography was evaluated with regard to presence or absence of flow in the mid portion, portal segment, and hepatic segment of the shunt. The maximal peak velocity was measured in the mid portion of the shunt. For identifying and quantifying stenoses, the percentage of luminal diameter reduction was calculated at the tightest part of the shunt. Shunt angiography and measurements of portosystemic pressure gradients were independently evaluated and compared with the sonographic findings. RESULTS: Flow visualization on unenhanced color Doppler sonography was significantly improved through the use of power Doppler sonography and contrast-enhanced color Doppler and power Doppler sonography (p < .01). Between contrast-enhanced power Doppler and contrast-enhanced color Doppler sonography, a significant difference was found in the portal and hepatic segments (p < .05). All shunt stenoses (n = 8) and occlusions (n = 3) were revealed by power Doppler sonography, whereas color Doppler sonography failed to reveal six of eight stenoses. Compared with unenhanced sonography, the quality of spectral duplex sonography was improved in eight patients after contrast enhancement (p < .05). Maximal peak velocity ranged from 54 to 252 cm/sec (mean +/- SD, 132.7 +/- 52.1 cm/sec) in normal shunts and from 24.5 to 70.0 cm/sec (mean +/- SD, 45.0 +/- 18.9 cm/sec) in stenosed shunts. No correlation was found between maximal peak velocity and portosystemic pressure gradients (r = .28). CONCLUSION: Unenhanced power Doppler and contrast-enhanced color and power Doppler sonography can be helpful in the assessment of TIPS status in patients who previously underwent unsatisfactory sonography. These techniques may allow anatomic evaluation and quantification of shunt stenosis in most patients. Contrast enhancement may also considerably improve the quality of spectral duplex sonography.     

Small solid renal lesions: usefulness of power Doppler US

PURPOSE: To evaluate whether the vascular pattern at power Doppler ultrasonography (US) improves diagnostic accuracy in small solid renal lesions over that at gray-scale US. MATERIALS AND METHODS: Gray-scale and power Doppler US were performed prospectively in 64 small (1.5-3.0-cm-diameter) solid renal lesions (26 renal cell carcinomas [RCCs], 34 angiomyolipomas, two oncocytomas, two pseudotumors). At gray-scale US, echogenicity and homogeneity of the lesion, an anechoic rim, intratumoral cysts, shadowing, or a central scar were sought. At power Doppler US, the vascular distribution was divided into four patterns. RESULTS: Findings at gray-scale US included an anechoic rim or intratumoral cysts in 20 of 26 RCCs (77%) and the two oncocytomas. Shadowing was seen in seven of 34 angiomyolipomas (21%). Echogenicity, homogeneity, and a central scar were not pathognomonic. At power Doppler US, pattern 3 (peripheral) or 4 (mixed penetrating and peripheral) was seen in all RCCs, seven of 34 angiomyolipomas, and the two oncocytomas. Pattern 1 (intratumoral focal) or 2 (penetrating) was seen in 27 angiomyolipomas. Pattern 1 or 2 was characteristic of angiomyolipoma. The rate of correct diagnosis was significantly increased with combined US (78%) as compared to that with gray-scale (42%) or power Doppler (45%) US alone. CONCLUSION: The vascular distribution at power Doppler US could add important information to gray-scale US findings for differential diagnosis of small solid renal lesions.     

Differentiation of benign and malignant cervical lymph nodes with color Doppler sonography

OBJECTIVE: This study proposed to evaluate the efficacy of color Doppler sonography in detecting possible differences in blood flow patterns between malignant and benign cervical lymph nodes. SUBJECTS AND METHODS: During a period of 12 months, the palpable cervical lymph nodes of 48 untreated patients were prospectively evaluated with color Doppler sonography and Doppler flow wave analysis. Histopathologic diagnoses were obtained by sonographically guided fine-needle aspiration biopsy and/or excisional biopsy. RESULTS: We found 16 benign lymph nodes (four were tuberculous lymphadenitis, four were reactive hyperplasia, and eight were unspecified) and 32 malignant lymph nodes (13 were squamous cell carcinomas, nine were adenocarcinomas, four were small-cell carcinomas, three were lymphomas, and three were miscellaneous). Color Doppler flow patterns were seen in six (38%) of the 16 benign lymph nodes and in 29 (91%) of the 32 malignant lymph nodes. Twenty-six (81%) of the 32 malignant lymph nodes had abnormal flow patterns, with resistance indexes less than 0.6. However, three (19%) of the 16 benign lymph nodes also had abnormal flow patterns, and only seven (54%) of 13 squamous cell carcinomas had abnormal flow patterns. CONCLUSION: Color Doppler sonography has limited clinical value in differentiating malignant from benign cervical lymph nodes and in obviating biopsy.     

Temporal variability of vena contracta and jet areas with color Doppler in aortic regurgitation: a chronic animal model study

OBJECTIVE: The purpose of our study was to determine the temporal variability of regurgitant color Doppler jet areas and the width of the color Doppler imaged vena contracta for evaluating the severity of aortic regurgitation. METHODS: Twenty-nine hemodynamically different states were obtained pharmacologically in 8 sheep 20 weeks after surgery to produce aortic regurgitation. Aortic regurgitation was quantified by peak and mean regurgitant flow rates, regurgitant stroke volumes, and regurgitant fractions determined using pulmonary and aortic electromagnetic flow probes and meters balanced against each other. The regurgitant jet areas and the widths of color Doppler imaged vena contracta were measured at 4 different times during diastole to determine the temporal variability of this parameter. RESULTS: When measured at 4 different temporal points in diastole, a significant change was observed in the size of the color Doppler imaged regurgitant jet (percent of difference: from 31.1% to 904%; 233% +/- 245%). Simple linear regression analysis between each color jet area at 4 different periods in diastole and flow meter-based severity of the aortic regurgitation showed only weak correlation (0.23 < r < 0.49). In contrast, for most conditions only a slight change was observed in the width of the color Doppler imaged vena contracta during the diastolic regurgitant period (percent of difference, vena contracta: from 2.4% to 12.9%, 5.8% +/- 3.2%). In addition, for each period the width of the color Doppler imaged vena contracta at the 4 different time periods in diastole correlated quite strongly with volumetric measures of the severity of aortic regurgitation (0.81 < r < 0.90) and with the instantaneous flow rate for the corresponding period (0.85 < r < 0.87). CONCLUSIONS: Color Doppler imaged vena contracta may provide a simple, practical, and accurate method for quantifying aortic regurgitation, even when using a single frame color Doppler flow mapping image.     

Nizatidine in combination with amoxycillin and clarithromycin in the treatment of Helicobacter pylori infection

BACKGROUND: We used dynamic magnetic resonance imaging (MRI) to study breast lesions in 13 women. METHODS: We observed differences in contrast uptake between benignancy and malignancy in 14 suspicious breast lesions. Three-dimensional (3D) gradient echo sequences were obtained before and after administration of gadolinium-based contrast medium (0.16 mmol/kg). The percentage of signal increase in lesions was measured in a series of five 90-second sequences, and time-enhancement patterns were correlated with pathologic diagnoses. RESULTS: Seven benign lesions and three breast cancer recurrences showed less than 185% signal increase at 90 seconds after contrast administration. Three new breast cancers and one recently biopsied benign lesion showed more than 185% signal increase at 90 seconds. CONCLUSION: Using this MRI technique, we can discriminate between new breast cancers (more than 185% early signal increase) and breast cancer recurrence and/or benign lesions (less than 185% early signal increase) but cannot distinguish recurrent from benign lesions.     

Gastrointestinal submucosal tumors: evaluation with endoscopic US

PURPOSE: To describe the endoscopic ultrasound (US) features of benign versus malignant submucosal tumors throughout the gastrointestinal tract. MATERIALS AND METHODS: One hundred nine patients aged 24-81 years suspected to have submucosal tumors (11 esophageal, 41 stomach, 24 duodenal, and 33 colorectal tumors) at barium studies or endoscopy underwent endoscopic US. The layer of origin, internal echo pattern, and lesion margin were analyzed by means of consensus and independent interpretation by three radiologists. RESULTS: Endoscopic US findings revealed several distinct patterns among various submucosal tumors. Sixteen (94%) of the 17 homogeneous lesions with histopathologic findings of malignancy were hypoechoic, although 29 (43%) of the 68 homogeneous lesions with histopathologic findings of benignity were similarly hypoechoic. Homogeneous lesions that were anechoic, of intermediate echogenicity, or hyperechoic were almost exclusively benign (39 [98%] of 40). In contrast, 23 (96%) of the 24 malignant lesions were heterogeneous (n = 7) or homogeneously hypoechoic (n = 16). The sizes of benign and malignant lesions were significantly different (P < .05). There was no significant difference in the echo pattern (i.e., homogeneous versus heterogeneous), but there was a significant difference in the proportion of hypoechoic versus nonhypoechoic lesions (anechoic, hyperechoic, or of intermediate echogenicity; P < .001). CONCLUSION: The differential diagnosis of gastrointestinal submucosal tumors is assisted with endoscopic US.     

Visually discernible myocardial echocardiographic contrast after intravenous injection of sonicated dextrose albumin microbubbles containing high molecular weight, less soluble gases

OBJECTIVES: The central hypothesis of this study was that microbubble survival, and subsequent left ventricular and myocardial ultrasound contrast, could be improved by altering microbubble gas to consist of a higher molecular weight (less diffusible) and less soluble gas. BACKGROUND: Microbubble survival after intravenous injection is shortened because of rapid diffusion of blood-soluble room air gases (nitrogen and oxygen) across the permeable bubble membrane into blood. METHODS: Thirteen open chest dogs received intravenous injections of a constant dose of sonicated dextrose albumin that was incubated with either room air or 100% nitrogen, 100% helium or 100% sulfur hexafluoride. Nitrogen (100%) is less blood soluble than room air, whereas helium and sulfur hexafluoride are the least soluble. Sulfur hexafluoride has the slowest diffusion rate. To further decrease the diffusion rate, each sample was administered during inhalation of room air and again during brief inhalation of the same gas with which it had been incubated. RESULTS: The highest peak videointensity in the left ventricular cavity was produced by the sonicated dextrose albumin incubated with sulfur hexafluoride, the gas having lowest blood solubility and diffusion rate, while sulfur hexafluoride was briefly inhaled during the period of intravenous injection (peak videointensity 139 +/- 10 vs. 54 +/- 11 for room air-exposed sonicated dextrose albumin, p < 0.001). Myocardial contrast was visually evident in > 80% of the intravenous injections of sulfur hexafluoride-exposed sonicated dextrose albumin when the agent was given as an 8-fold concentrated sample during brief inhalation of sulfur hexafluoride. CONCLUSIONS: Visual myocardial echocardiographic contrast is possible after intravenous injection of sonicated dextrose albumin if the microbubbles contain a gas with low blood solubility and diffusivity.     

Effect of ethanol on myocardial infarct size in a canine model of coronary artery occlusion-reperfusion

INTRODUCTION: We investigated the effectiveness of Levovist (SHU508A, Schering AG, Berlin, Germany) in the characterization of breast lesions. MATERIAL AND METHODS: June, 1996, to May, 1997, we studied 29 solid lesions in 29 patients (aged 17 to 83 years); our patients were 28 women and 1 man. The 29 solid lesions were 20 carcinomas (15 infiltrating ductal carcinomas, 4 ductal carcinomas in situ, 1 lobular carcinoma in situ), 6 fibroadenomas, 1 suspected postoperative recurrence and 2 apparently benign lesions. We used parameters suitable for the study of slow flows. A single bolus of contrast agent (300 mg/mL) was administered at 1-2 mL/s. Before Levovist injection, we studied the lesion signal intensity and the number of vascular poles. After contrast administration we re-evaluated both these parameters and studied the changes or presence of vessels undetected on the previous images. We also investigated the beginning and duration of enhancement and the presence of vessels inside and outside the lesions. RESULTS: We observed no signal enhancement in 17% of cases, mild enhancement in 7% and strong enhancement in 76% of cases. We found 3 more vascular poles (17%) in 5 lesions and 4 more poles in 3 lesions (10%). Increased vascularization was seen inside the lesion in 17% of cases, inside and outside it in 41% and only outside in 35% of cases. Carcinomas showed a rapid and long-lasting enhancement, while fibroadenomas showed a later and weaker enhancement. CONCLUSIONS: Levovist can be useful in the differential diagnosis of benign from malignant lesions, of recurrences from postoperative fibrosis, as well as in the staging and follow-up of the patients treated with neoadjuvant chemotherapy.     

Exhumation and no end. A comparative analysis]

INTRODUCTION: In the last 25 years, random trials on the advantages of combined surgery and irradiation/chemotherapy of breast cancer demonstrated similar survival rates to those of massive surgery. However, both irradiation and chemotherapy have advanced and now yield good local control of the disease, so that even large breast cancers can be made operable. Breast cancer follow-up is carried out with imaging and clinical examinations to detect early locoregional recurrences, contralateral lesions and distant recurrences: to this purpose, we carried out a comparative study of all imaging modalities. MATERIAL AND METHODS: We retrospectively reviewed the data of 42 breast cancer (T2-T3 N0-N+) patients of the Senology Center of the Catholic University (Rome, Italy) treated with irradiation and/or chemotherapy for tumor debulking to permit conservative surgery. We investigated the sensitivity and the indications of mammography, B-mode and color Doppler US and MRI in measuring the exact tumor size and detecting locoregional metastatic nodes. RESULTS: After 3 years' treatment, our recurrence rate (19%) is a little higher than those in the major international trials (4.2-9% and 5 tears). The recurrence was on the surgical scar in 75% of cases (6/8), while multifocal tumors were found in 25% of cases. US was the most accurate method in measuring tumor size in 90% of cases (18/20), while mammography frequently overstaged the lesion and yielded exact measurements in 65% of cases (13/20). MRI was as accurate as US, but this technique is too expensive and little available in Italy. US accurately diagnosed lymph node recurrences (70% sensitivity), but MR rate was even higher (80%), while mammography and color Doppler US had only 5-10%. As for treatment outcome, an irregular and blurred nodule or multifocal lesions at mammography indicate poor/no response, while a much smaller radial scar than at previous similar follow-ups indicates treatment success. CONCLUSIONS: When correctly integrated, mammographic, US and MR patterns permit exact tumor size measurement and show possible locoregional lymph node involvement in the patients submitted to conservative surgery and irradiation/chemotherapy. In contrast, color Doppler findings remain poorly specific in this disease, with about 55% sensitivity. Therefore, radiologic studies, with clinical and laboratory data, have a major prognostic value in assessing the biological response to combined treatment.     

Peripheral washout sign on contrast-enhanced MR images of the breast

PURPOSE: To assess the value of the peripheral washout sign on delayed contrast material-enhanced magnetic resonance (MR) images in differentiation of benign from malignant breast masses. MATERIALS AND METHODS: In 49 women with 79 breast lesions (55 malignant and 24 benign), dynamic contrast-enhanced MR imaging was performed every 90 seconds during the first 7 minutes and repeated at 10, 20, 30, 40, 50, and 60 minutes after injection of contrast material. Qualitative analysis of the images was performed to evaluate the presence of the peripheral washout sign (a hypointense zone in the periphery of the lesion relative to the center). Quantitative analysis of the images was performed by measuring the signal intensity of the periphery and center of the lesions. RESULTS: The peripheral washout sign was seen in 28 (51%) of the 55 carcinomas on delayed contrast-enhanced MR images (> 10 minutes). Quantitative analysis demonstrated different enhancement profiles of the periphery and center of these lesions. The periphery showed early increase and decrease of enhancement, while the center showed gradual increase and persistent enhancement. The peripheral washout sign was not seen in any of the benign lesions. Specificity was 100% and sensitivity was 51% for diagnosis of breast carcinoma. CONCLUSION: Peripheral washout may be a reliable sign of malignancy on delayed contrast-enhanced MR images of the breast.     

Color Doppler regurgitant jet area for evaluating eccentric mitral regurgitation: an animal study with quantified mitral regurgitation

OBJECTIVES: The purpose of the present study was to rigorously evaluate the accuracy of the color Doppler jet area planimetry method for quantifying chronic mitral regurgitation. BACKGROUND: Although the color Doppler jet area has been widely used clinically for evaluating the severity of mitral regurgitation, there have been no studies comparing the color jet area with a strictly quantifiable reference standard for determining regurgitant volume. METHODS: In six sheep with surgically produced chronic mitral regurgitation, 24 hemodynamically different states were obtained. Maximal color Doppler jet area for each state was obtained with a Vingmed 750. Image data were directly transferred in digital format to a microcomputer. Mitral regurgitation was quantified by the peak and mean regurgitant flow rates, regurgitant stroke volumes and regurgitant fractions determined using mitral and aortic electromagnetic flow probes. RESULTS: Mean regurgitant volumes varied from 0.19 to 2.4 liters/min (mean [+/- SD] 1.2 +/- 0.59), regurgitant stroke volumes from 1.8 to 29 ml/beat (mean 11 +/- 6.2), peak regurgitant volumes from 1.0 to 8.1 liters/min (mean 3.5 +/- 2.1) and regurgitant fractions from 8.0% to 54% (mean 29 +/- 12%). Twenty-two of 24 jets were eccentric. Simple linear regression analysis between maximal color jet areas and peak and mean regurgitant flow rates, regurgitant stroke volumes and regurgitant fractions showed correlation, with r = 0.68 (SEE 0.64 cm2), r = 0.63 (SEE 0.67 cm2), r = 0.63 (SEE 0.67 cm2) and r = 0.58 (SEE 0.71 cm2), respectively. Univariate regression comparing regurgitant jet area with cardiac output, stroke volume, systolic left ventricular pressure, pressure gradient, left ventricular/left atrial pressure gradient, left atrial mean pressure, left atrial v wave pressure, systemic vascular resistance and maximal jet velocity showed poor correlation (0.08 < r < 0.53, SEE > 0.76 cm2). CONCLUSIONS: This study demonstrates that color Doppler jet area has limited use for evaluating the severity of mitral regurgitation with eccentric jets.