Diagnosis of vasa previa with ultrasound and color flow Doppler: a case report

Ultrasound and Doppler imaging have proven to be valuable antepartum diagnostic tools for the early recognition of vasa previa. Recent reports have demonstrated that successful detection and timely management can subsequently reduce the risk of a life-threatening fetal hemorrhage. We present the fourth reported case of vasa previa detected antenatally by ultrasound. While conscientious attention to the risk factors and a high index of clinical suspicion remain important considerations, we believe that ultrasound and color Doppler flow analysis represent a highly sensitive diagnostic tool for those patients at risk. In the past, antenatal diagnosis has relied on insensitive and inconclusive means, often only after signs of fetal compromise have become apparent. Sonography has been demonstrated to offer reduced fetal mortality and therefore must be considered the new standard of care for management of suspected vasa previa.     

Antenatal diagnosis of velamentous umbilical cord insertion and vasa previa with color Doppler imaging

The effect of various anionic surfactants on the initial rate of 5-aminosalicylic acid peroxidation with horseradish peroxidase was studied. With increasing surfactant concentration, this rate first decreased, then increased, and again decreased. We conclude that these changes were due to an inhibition of the enzyme, a subsequent change in the enzyme conformation accompanied by the enhanced accessibility of its active site to the substrate, and the final protein denaturation, respectively.     

Stage I ovarian cancer by transvaginal color Doppler sonography: a report of 18 cases

PURPOSE: To evaluate the tolerability and 24 hours efficacy of a new anti-hypertensive drug: cilazapril. METHODS: In an open non comparative study 20 hypertensive patients (16 females, age from 30 to 60 years, average = 49.4) were followed for 6 weeks: 2 wash out and 4 treatment (5 mg OD). Blood pressure (BP) was measured by casual and ambulatory blood pressure monitoring (ABPM) readings. RESULTS: Comparing washout and treatment periods, ABPM averages both for systolic and diastolic BP (mmHg) showed significant decrease in 24 hours, during day and night sub periods. The decrease was not significant between averages considering the "early morning rising pressure" sub period. Heart rate averages showed significant reduction at all sub periods except during night. Adverse effects were mild and resolved spontaneously (n = 3, 15%). CONCLUSION: Cilazapril seems to be efficacious as antihypertensive. Tolerability is excellent. It preserved circadian rhythm despite significantly reducing blood pressure at all periods evaluated except early morning. A bradycardic effect observed mostly during day period should be better evaluated.     

Reliability of color Doppler and power Doppler sonography in the evaluation of intussuscepted bowel viability

In two similar cases of irreducible intussusception with wall necrosis and perforation, symptoms had begun 24 h before admission and the plain radiographs showed signs of small-bowel obstruction. The sonographic (US) appearances, however, were different: color Doppler (CD) US showed vascular flow in the intussuscepted bowel in one case and no flow in the other. After radio-clinical assessment, both children underwent surgery and an intestinal resection had to be performed, manual reduction being impossible. The reliability of the US findings and the prognostic value of CD and power Doppler US in determining the viability of the intussuscepted bowel are discussed with a review of the literature.     

Intrarenal varices: demonstration by color Doppler sonography

Idiopathic intrarenal varices are a rare disease, and only a few cases have been reported. We encountered a patient with intrarenal varices in whom color Doppler sonography was useful for diagnosing and demonstrating this disease, especially with 3D reconstruction of blood flow, which we began using recently.     

Solitary hepatic lesions with a hypoechoic rim: value of color Doppler sonography

OBJECTIVE: A hypoechoic rim around a focal liver lesion as revealed by conventional sonography may be present in malignant liver lesions as well as in benign liver lesions. This study evaluated the potential of color Doppler sonography in differentiating various focal liver lesions with a hypoechoic rim. CONCLUSION: Color Doppler sonography may be helpful in distinguishing focal nodular hyperplasia (FNH) from other focal liver lesions. The characteristic finding of blood flow within the hypoechoic rim of FNH is most likely caused by small vessel abnormalities that have previously been described for FNH.     

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.     

Conventional color Doppler velocity sonography versus color Doppler energy sonography for the diagnosis of acute experimental torsion of the spermatic cord

OBJECTIVE: We compared color Doppler velocity sonography and color Doppler energy sonography for the diagnosis of spermatic cord torsion in a canine model and determined the degree of torsion necessary to acutely halt testicular blood flow. MATERIALS AND METHODS: Spermatic cord torsion was created in five dogs by exposing and rotating the ipsilateral testis 0 degree, 180 degrees, 270 degrees, 360 degrees, 450 degrees, and 540 degrees. Detorsion followed. The testicles were scanned at each torsion stop using both color Doppler velocity sonography and color Doppler energy sonography. Doppler parameters were optimized (by phantom and test scans) and maintained at a tolerable noise level throughout the experiment. Readers who were unaware of the degree of torsion compared flow in the rotated and contralateral control testes. RESULTS: Flow became undetectable by color Doppler velocity sonography and color Doppler energy sonography at 450 degrees in four of five cases and at 540 degrees in one of five cases. We found no significant difference between the velocity and the energy techniques for detecting this absence of flow (p > .05, Wilcoxon test). We found a significant difference in degree of flow for both techniques when comparing controls and all degrees of torsion combined (p < .006, Mann-Whitney test), but significance was achieved at lesser degrees of torsion with the velocity technique than with the energy technique (180 degrees and 360 degrees, respectively, Wilcoxon test). CONCLUSION: Color Doppler energy sonography was not significantly more sensitive than color Doppler velocity sonography for the diagnosis of spermatic cord torsion in this model. Complete occlusion of arterial inflow occurred at 450-540 degrees of torsion.     

Three-dimensional power Doppler sonography of tumor vascularity

We used existing data on hepatitis C prevalence, injection-related hepatitis C transmission and needle use in prisons and new data on infectiousness, to estimate the size of study required to detect injection-related hepatitis C in UK prisons. A pilot study of 500 prisoners followed for 10 weeks would have a 65% chance of detecting a hepatitis C seroconversion, conservatively assuming one injection per prisoner per week, and a 3% transmission rate per injection, but uncertainty might persist as to whether transmission had occurred during a short incarceration or before it. If the actual transmission rate was 10%, as recently documented, then such a study would have more adequate statistical power. A definitive study of 3000 prisoners for 10 weeks would expect to detect about six seroconversions, even with conservative estimates of injection frequency and transmission rate. Adequate design and power of these studies is important because of the complacency that could result from false-negative findings. We suggest six risk-factor themes that studies should document.     

Diagnosis of post-partum ovarian vein thrombophlebitis by color Doppler ultrasonography: about 10 cases

BACKGROUND: Post-partum ovarian vein thrombosis is often overlooked or mistaken for other complications such as endometritis. Color Doppler ultrasonography is a very good diagnostic method when properly indicated and correctly interpreted according to clinical data. METHODS: This study reports ten cases that were retrospectively studied, during which color Doppler ultrasonography was used. The clinical signs and the results are reviewed. RESULTS: The lesions were clearly visualized in eight of the ten cases; one of the two failures resulted from a methodological fault (uninterpretable result); the other one was due to the lack of experience of the operator and nonrecognition of the clinical signs. Thrombosis appears as a hypoechogenic and tubular image. This type of examination is particularly indicated in the presence of certain clinical signs that were observed in our cases: fever and iliac pain are the main precursor signs, often associated with abdominal meteorism and slow digestive transit; provoked cul-de-sac pain during vaginal probing was the only constant sign, sometimes associated with painful swelling.     

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.     

Transvaginal pulsed and color Doppler sonography for the evaluation of adenomyosis

In an earlier paper, we reported our scoring system for the diagnosis of adenomyosis by gray scale transvaginal sonography. In this study we evaluated 44 benign uterine masses (adenomyosis and myomas) and seven uterine malignancies. We used transvaginal color and pulsed Doppler imaging to determine whether this technique is useful to differentiate adenomyosis from uterine malignancies. The peak systolic velocity and the resistive index of intratumoral vessels were studied. The differences in these parameters for adenomyosis and uterine malignancies were statistically significant. Our results suggest that this technique is useful to differentiate adenomyosis from uterine malignancies.     

Placenta accreta: evaluation with color Doppler US, power Doppler US, and MR imaging

PURPOSE: To determine the value of transabdominal ultrasound (US), transvaginal US, color Doppler US, power Doppler US, and magnetic resonance (MR) imaging in the diagnosis of placenta accreta. MATERIALS AND METHODS: Nineteen patients in the third trimester of pregnancy who were at risk for placenta accreta underwent color Doppler and power Doppler US; 18 patients also underwent MR imaging. Images were interpreted prospectively for signs of accreta by two reviewers. The reviewers' confidence in their diagnosis was graded on a five-point scale. RESULTS: Outcomes at delivery were as follows: normal placenta (n = 11), hysterectomy owing to uncontrollable bleeding (n = 1), and placenta accreta (n = 7). Five cases of lower-uterine-segment placenta accreta were diagnosed with a high level of confidence with vaginal and power Doppler US. In one patient with a posterior placenta who had previously undergone myomectomy, MR imaging enabled the diagnosis of placenta accreta, which was not well depicted at US. CONCLUSION: In patients with a history of uterine scars, vaginal US with power Doppler US performed well in the evaluation of lower-uterine-segment placenta accreta. MR imaging depicts posterior placenta accreta.     

Transcranial power mode Doppler duplex sonography of intracranial aneurysms

Recent events have challenged our health system to increase access to and provide high quality care for patients near the end of life. Simultaneously, Medicare is developing review policies to determine eligibility for hospice patients with select noncancer diagnoses. The purpose of this study was to determine whether the proposed policies met one of their chief goals: accurate identification of patients with a less-than-six-months prognosis. Only 35 percent of 104 patients who died within six months of admission to the hospice used for this study, LifePath Hospice, met the Medicare proposed criteria for hospice eligibility. The median and mean survival time of the sample was 14 and 30 days respectively. Based on this review, it is recommended that Medicare alter their proposed review policies and not limit access to hospice eligible patients who desire and are in need of such services.     

Prenatal diagnosis of microcephaly assisted by vaginal sonography and power Doppler

The study population consisted of ninety patients between the ages of 22 and 64 years. All had mild or moderate hypertension at rest and were subjected to exercise tests using a cycloergometer. The sex ratio for the patients was 0.875. Blood pressure and heart rate were recorded at three time points, at three minute intervals. The initial load was thirty watts for men and 25 watts for the women. A graph of changes in blood pressure with exercise was produced for each type of antihypertensive drug or combination of drugs. At least nine patients were treated with each type of drug or combination, and blood pressure and heart rate were recorded during exercise to produce the exercise blood pressure profile. Healthy adults generate curves that lie between Y'1 = 0.5X + 108.43 and Y"1 = 0.34X + 83.95 [2]. Any patient generating a curve lying between these two limits was regarded as having a normal exercise blood pressure profile. This study identified two groups of hypertension treatments with respect to exercise blood pressure profile. Abnormal exercise blood pressure profiles were obtained with treatments involving inhibition of calcium receptor activity, diuretics and central antihypertensive drugs. Normal exercise blood pressure profiles were obtained with treatments involving the inhibition of adrenoreceptor activity, alone or in conjunction with a diuretic, and with combined central antihypertensive drug and diuretic treatment.     

Differentiation of benign and malignant cervical lymph nodes: value of B-mode and color Doppler sonography

AIM: Acute mesenteric ischemia is difficult to diagnose and is combined with a high mortality. In a retrospective analysis it was investigated how to improve the poor prognosis of the disease. PATIENTS AND METHODS: Between January 1988 through December 1994 a total of 46 patients were operated on for acute mesenteric ischemia. Mesenteric artery occlusion was present in three quarters of the cases (n = 35). These were analysed according to symptoms, diagnosis, mechanism of occlusion, operative procedure and prognosis. Distribution of gender was almost balanced (19 women, 16 men) with a median age of 70.5 years. RESULTS: Embolic arterial occlusion was predominant (n = 22). Most frequently, the superior mesenteric artery was exclusively concerned (n = 22). Serum levels of lactate and leucocytes were preoperatively elevated in over 90% (median values: lactate 53 U/l, leucocytes 15050/ml). In 16 patients diagnosis was made on the ground of clinical parameters and/or angiography, but 19 patients were not diagnosed until operation. 19 patients were operated within 6 hours, 12 patients within 24 hours after admission (> 24 hours: n = 4). Vascular reconstructive procedures only, such as thrombectomy and/or aortomesenteric bypass were performed in 9 cases, in a further 7 cases combined with bowel resection. Bowel resection alone was done in 7 patients, 12 patients had only diagnostic laparotomy. 13 patients survived, 10 of them had been treated with vascular reconstruction. CONCLUSION: Acute mesenteric ischemia ought to be suspected in every patient with uncertain abdominal pain, because only early diagnosis can improve prognosis. Measurement of serum lactate is diagnostically helpful, although not proving. In case of elevated lactate levels and uncertain abdominal symptoms angiography of the mesenteric vessels should be performed early. At operation, blood flow in the mesenteric arteries should be restored whenever possible.     

Diagnosis of cerebral circulatory arrest with Doppler sonography. Results of a survey

OBJECTIVES: To assess the feasibility and potential diagnostic usefulness of colour-Doppler flow imaging (CDFI) to detect complications of supra-aortic vascular bypass grafts in Takayasu's arteritis (TA). DESIGN: A prospective study. MATERIALS: Nine supra-aortic grafts in six patients with Takayasu's arteritis. METHODS: The minimal, maximal, and true colour-flow image diameters of the lumens of the grafts were measured and stenoses, occlusions, and dilatations were evaluated and compared with angiographic findings. RESULTS: The sensitivity for detection in > 50% stenoses and in total occlusions was 75% while specificity was 100%. Only one 40% stenosis had been overlooked in whole. The maximal difference of stenosis by two methods was otherwise 20%. CONCLUSIONS: CDFI was in general able to expose stenoses in supra-aortic grafts, but the lack of visibility of some grafts throughout their length cause the false results. It appears that some angiographies can be replaced by CDFI and that this is a suitable method for follow-up in symptom-free patients with grafts.