Assessment of hyperemia in acute appendicitis: Comparison between power Doppler and color Doppler sonography

The purpose of our study was to compare power Doppler sonography (US) and conventional color Doppler US in the diagnosis of acute appendicitis by revealing local signs of hyperemia. One hundred consecutive patients (46 males and 54 females, ages 7–61 years; mean, 24.7 years) with clinically suspected acute appendicitis were prospectively examined with power Doppler US and conventional color Doppler US. Of 38 patients who subsequently underwent surgery, appendicitis was proven in 34. The remaining 62 patients who were not submitted to surgery had no clinical evidence of appendicitis over a 2- to 6-month follow-up. At gray-scale US, the appendix was visualized in 30 (88.2%) of the 34 cases with pathologically proven acute appendicitis. Power Doppler US depicted a moderate to marked hypervascularity of the appendiceal wall and surrounding mesoappendix in 28 (93.3%) of these 30 patients. At conventional color Doppler US, flow signal within the appendiceal wall and surrounding mesoappendix was shown in only 21 (70%) of 30 cases (P<0.05). No false-positive diagnosis was made at either power or color Doppler US among the 62 patients without appendicitis. Power Doppler US is more sensitive than conventional color Doppler imaging for revealing signs of local hyperemia in acute appendicitis.     

Appendiceal involvement in Crohn's disease: gray-scale sonography and color Doppler flow features

OBJECTIVE: The objective of our study was to evaluate appendiceal involvement in Crohn's disease with gray-scale and color Doppler sonography and differentiate it from acute appendicitis. MATERIALS AND METHODS: Analysis of the sonographic examinations was performed over 5 years in 190 patients with an established diagnosis of Crohn's disease. Data analyzed were as follows: visualization of the appendix; thickness and color Doppler signal (grade 0, 1, or 2) of the appendix and adjacent intestinal loop (cecum, terminal ileum, or both); involvement of other intestinal segments; and abscesses. The findings were compared with those of 49 consecutive patients with sonographic findings of acute appendicitis. RESULTS: Thirty-nine patients with Crohn's disease (21%) had appendicular involvement. All but one patient showed thickening of the terminal ileum, and 46% of patients also showed thickening of the cecum. The thickness of the ileum was more than 5 mm (only the anterior wall) in 64% of patients. Appendicular hyperemia was seen in 72% of patients. Involvement of other segments was seen in 23 patients (59%) and adjacent abscesses in six (15%). Irregular thickness of the submucosa was seen in nine cases (23%) and fibrofatty proliferation in 19 (49%). In patients with ileocecal regional disease, ileum thickness of more than 5 mm and visible color in the ileum were the most valuable signs, both for the diagnosis of Crohn's disease and to differentiate it from acute appendicitis (positive predictive value, 96%; negative predictive value, 74%). CONCLUSION: Appendicular involvement in Crohn's disease is a relatively frequent event (21%). Sonography and color Doppler sonography may be useful for differentiating Crohn's disease with appendicular involvement from acute appendicitis.     

Acute appendicitis in children: evaluation with US

During a 4-month period, high-resolution ultrasonography (US) was used to prospectively evaluate 70 children with clinically suspected acute appendicitis. Thirty-five US scans showed a noncompressible appendix with maximal outer diameters greater than 6 mm. This finding was considered positive for the diagnosis of acute appendicitis. Thirty-one of these 35 patients had acute appendicitis documented by surgical and pathologic findings. The remaining four patients were observed, and their symptoms resolved. Thirty-five patients had US scans considered negative for appendicitis. Seventeen of these patients had US findings positive for other conditions including mesenteric adenitis, ileitis, intussusception, Crohn disease, and Burkitt lymphoma. In this series US enabled diagnosis of acute appendicitis with a sensitivity of 94%, a specificity of 89%, and a predictive accuracy of 91%. Diagnosis of acute appendicitis can be made with US with the same accuracy in children as has been previously reported in series of adult patients. The use of US in clinically ambiguous cases may allow earlier diagnosis, prevention of perforation, and decreased complications in the pediatric patient with acute appendicitis.     

Primary torsion of the greater omentum: Color Doppler sonography and CT correlated with surgery and pathology findings

Primary torsion of the greater omentum is a rare cause of acute abdomen commonly diagnosed at surgery performed for appendicitis. We report nine cases of omental torsion who underwent surgery and correlate their preoperative color Doppler ultrasonography (US) and computed tomography (CT) findings with the surgical and pathological findings to assess the value of US and CT in the diagnosis of omental torsion. US findings of omental torsion correlated with the operative and pathological findings in seven patients and the diagnosis was missed in two patients suspected to have ruptured appendix. CT findings of omental torsion correlated with the operative and pathological findings in all five patients who did CT. US and CT scanning are useful for preoperative diagnosis of omental torsion.     

Omental infarction in children: color Doppler sonography correlated with surgery and pathology findings

OBJECTIVE: The objective of our report is to describe color Doppler sonography findings of omental infarction and correlate them with surgical and pathology findings. Ten children underwent preoperative gray-scale and color Doppler sonographic examinations; omental infarction was confirmed at surgery. CONCLUSION: Color Doppler sonography findings were reviewed and correlated with surgical and pathology findings. Color Doppler sonography features of idiopathic omental infarction differ from those of infarction secondary to omental torsion.     

Diagnostic role of echography in acute appendicitis in children]

Eighty-seven pediatric patients with suspected acute appendicitis underwent high-resolution US with graded abdominal compression. The study was limited to the patients with a questionable clinical diagnosis, accounting for about 40% of the patients examined for acute appendicitis in our Institution. US had 87.3% accuracy, 81.5% sensitivity, and 90% specificity. The main US findings in the positive cases were: visualization of the appendix as a tubular non-compressible structure, with a diameter of 5 mm or more, symmetric/asymmetric wall thickening, possible presence of appendicoliths and variable appearance of the central echogenic layer (preserved, doubled for lumen dilatation, partially/totally lost). The above US findings were grouped in 3 basic patterns: type I (thickened appendix with no structural abnormalities) appeared to be related to non-suppurative and phlegmonous acute appendicitis; type II (detectable appendiceal abnormalities) was observed both in phlegmonous and in suppurative acute appendicitis; type III (pericecal complex mass, frequently with appendicoliths) was found in all cases of periappendiceal abscess. In our experience, the use of US in the diagnosis of acute appendicitis in children allowed a reduction by about 2/3 in the rate of unnecessary laparotomies. Such a finding emerges from the comparison with the results obtained in the 2 years prior to the use of US. The technique also allowed an unquestionable diagnosis of acute appendicitis or periappendiceal abscess to be made in a number of clinically equivocal cases, thus avoiding potentially harmful delays in diagnosis. On the other hand, the incidence of false-negatives on US is not negligible, which calls for a cautious clinical and US evaluation of all equivocal cases following no typical US pattern.     

Sonographic findings of Meckel's diverticulitis in children

OBJECTIVE: We know of only one previous study that has described the sonographic appearances of the inflamed Meckel's diverticulum in several cases (nine patients). Our study reviews sonographic, clinical, and pathologic findings in 10 patients with an inflamed Meckel's diverticulum. We also describe unique findings on color Doppler sonography for two of our patients. CONCLUSION: Sonographic findings of an inflamed Meckel's diverticulum may mimic findings for acute appendicitis or intestinal duplication. In patients with rectal bleeding due to diverticulitis, the visualization of a tubular hyperechoic structure on sonography is suggestive of Meckel's diverticulum. The inflamed Meckel's diverticulum may present as a cyst, but its mucosal layer is more irregular than that found in an intestinal duplication. We found that routine color Doppler sonography revealed anomalous vessels and signs of inflammation on the wall of the Meckel's diverticulum.     

Contrast-enhanced power Doppler US in the diagnosis of acute appendicitis

INTRODUCTION/OBJECTIVE: To determine the value of power Doppler (PD) ultrasonography (US) and contrast-enhanced power Doppler (CEPD) US in the diagnosis of acute appendicitis and the prediction of histopathologic stages. METHODS AND MATERIAL: 50 patients with suspected acute appendicitis were evaluated by the same radiologist with PD US and CEPD US. Air micro bubbles stabilized by a granulate of "galactose and palmitic acid" were used as a contrast medium for sonography with the concentration of 400 mg/ml. PD US and CEPD US results were later correlated with the surgical and histopathologic findings. PD US and CEPD US findings were considered positive for appendicitis; if there was depiction of hyperemia in the wall of the appendix or if there was depiction of prominent peripheral vascularity when compared with normal soft tissues; and negative if both hyperemia and peripheral hyperemia were not prominent. RESULTS AND DISCUSSIONS: Of the 50 patients, 35 patients had histopathologically proven acute appendicitis. CEPD US showed prominent hyperemia in the appendiceal vessels or feeding vessels of the inflamed appendix, and resistance index (RI) calculations were easier. There was statistically significant difference between mean RI values of the normal appendix, suppurative appendicitis and gangrenous appendicitis. PD US has accuracy of 80%, sensitivity of 74% and CEPD US has 98%, and 100% in the diagnosis of acute appendicitis. CEPD US identified 100% of suppurative appendicitis and gangrenous appendicitis. CONCLUSION: CEPD US is a promising method in the diagnosis of acute appendicitis and determination of the inflammation stage.     

When appendicitis is suspected in children.

Acute appendicitis is the most common condition requiring emergent abdominal surgery in childhood. The clinical diagnosis of acute appendicitis is often not straightforward because approximately one-third of children with the condition have atypical clinical findings. The delayed diagnosis of this condition has serious consequences, including appendiceal perforation, abscess formation, peritonitis, sepsis, bowel obstruction, and death. Cross-sectional imaging with ultrasonography (US) and computed tomography (CT) have proved useful for the evaluation of suspected acute appendicitis. There has been a great deal of variability in the utilization of these modalities for such diagnosis in the pediatric population. The principal advantages of US are its lower cost, lack of ionizing radiation, and ability to assess vascularity through color Doppler techniques and to provide dynamic information through graded compression. The principal advantages of CT include less operator dependency than US, as reflected by a higher diagnostic accuracy, and enhanced delineation of disease extent in a perforated appendix.     

Testicular ischemia: color Doppler sonographic findings in five patients

We studied the findings on color Doppler sonography in five men with testicular ischemia (three with acute testicular torsion and two with testicular infarcts after herniorrhaphies). In all five cases, no intratesticular blood flow was identified on the symptomatic side, while normal blood flow was evident on the opposite side. In the three cases of acute torsion, no gray scale sonographic abnormalities were seen, and in the two cases of postoperative infarction, the abnormalities were nonspecific. These findings suggest that color Doppler sonography can be used to show decreased blood flow in cases of acute testicular ischemia and that it may have a role in evaluating patients with suspected testicular torsion.     

Impact of sonography in gouty arthritis: comparison with conventional radiography, clinical examination, and laboratory findings

OBJECTIVE: To explore the typical sonographic features of gray-scale and Power Doppler of acute and chronic gouty arthritis in conjunction with radiographic, clinical, and laboratory findings. MATERIALS AND METHODS: All hand, finger, and toe joints of 19 patients with acute and chronic gout were examined with gray-scale and Power Doppler sonography. The number and size of bone changes detected with sonography was compared to radiographic findings. Vascularization of the synovial tissue was scored on Power Doppler (grades 0-3), and was compared with clinical appearance, including swelling, tenderness, and redness (grades 0-3). RESULTS: In acute gout, mild to moderate echogenic periarticular nodules with sonotransmission and hypervascularization of the edematous surrounding soft tissue were found. In chronic gout, tophaceous nodules completely blocked transmission of US wave, leading to strong reflexion and dorsal shadowing in a minority of cases. No significant difference in the detection of large bone changes (>2mm) was found between sonography and radiography. However, gray-scale sonography was significantly more sensitive in the detection of small bone changes (p<0.001). Power Doppler scores were statistically significantly higher than clinical examination scores (p<0.001). DISCUSSION: Sonography is superior to radiographs in evaluating small bone changes. The inflammatory process in joints can be better detected with Power Doppler sonography than with clinical examination. Typical sonographic appearance of acute and in particular of chronic gout might provide clues on gouty arthritis that adds to the information available from conventional radiography, clinical, and laboratory findings.     

Is colour Doppler sonography a good method to differentiate normal and abnormal appendices in children?

AIM: To determine whether colour Doppler sonograms can be used to differentiate between the normal appendix and acute appendicitis. MATERIAL AND METHODS: This prospective study examined 50 consecutive children with suspected appendicitis using grey-scale and colour Doppler US. Appendicitis was diagnosed when the appendix diameter was greater than 6 mm. Blood flow on the appendiceal wall was measured and classified as non-existent (0 pixels), low (1-2), moderate (3-4) or abundant (>4). Likelihood ratios were calculated for each of these levels. The diagnosis of acute appendicitis was confirmed by pathological findings, and ruled out by clinical follow-up or pathological findings. RESULTS: Of the 50 patients examined, 24 had appendicitis and 26 had a normal appendix. For 25 of the patients with a normal appendix, appendicitis was ruled out by clinical follow-up, and for one patient, by pathological findings. The abnormal appendix was identified in all patients with appendicitis. In the group of 26 patients without appendicitis, the normal appendix was visualized in 23 cases, one of which was false positive (100% sensitivity, 96% specificity). Abnormal appendices showed moderate to abundant flow in 62% of the cases and non-existent or low flow in 38%. Normal appendices had non-existent or low flow in 82% of the cases, but moderate or abundant in 18%. Significant differences were only found when the number of pixels was >4. CONCLUSION: Although the vascularity of normal and inflamed appendices may be different, this difference was not a good diagnostic indicator of appendicitis.     

Imaging of the acute scrotum

The scrotum is a superficial structure and clinical examination is frequently not enough for making a specific diagnosis. In acute scrotal pain US can confirm the presumptive clinical diagnosis and provide additional relevant information. In testicular torsion, color-Doppler imaging has a central role since it has become possible to identify it at early stage by showing absence of perfusion in the affected testis before any gray-scale abnormality. Scintigraphy remains a satisfactory alternative in evaluating testicular torsion and should be used when color Doppler is inadequate, raising doubts about the suspected torsion. Diagnosis of torsion of testicular appendages is particularly difficult. Ischemic infarction shows a characteristic pattern at gray-scale and color-Doppler imaging, whereas hemorrhagic ischemia may require MRI. Inflammatory diseases of the scrotum can be easily investigated by echo color Doppler and conventional radiography, and CT can be particularly useful in the detection of gas bubbles. In scrotal trauma, scrotal hematoma, hematocele, intratesticular hematoma, and testicular rupture can be identified using gray-scale US with very good reliability. Magnetic resonance imaging is indicated when a small tear of tunica albuginea is suspected but not visualized on US. Received: 3 May 2000/Accepted: 8 June 2000     

Using gray-scale and color and power Doppler sonography to detect prostatic cancer

OBJECTIVE: We performed a prospective study to assess gray-scale and color and power Doppler sonography for the detection of prostatic cancer and to determine the impact of operator experience. SUBJECTS AND METHODS: Four radiologists with prior experience using gray-scale and Doppler imaging and four urologists with prior experience limited to gray-scale imaging performed sextant biopsies on 251 patients. Each biopsy site was prospectively scored for gray-scale and Doppler abnormality. RESULTS: Cancer was detected in 211 biopsy sites from 85 patients. Overall agreement between sonographic findings and biopsy results as measured with the kappa statistic was minimally superior to chance (kappa = 0.12 for gray-scale, kappa = 0.11 for color Doppler, kappa < or =0.09 for power Doppler). With respect to gray-scale diagnosis of cancer, the performance of radiologists (kappa = 0.12) and urologists (kappa = 0.13) was similar. With respect to power Doppler, the performance of radiologists (kappa = 0.09) was superior to that of urologists (kappa = -0.03, p<0.002). Among patients with at least one positive biopsy for cancer, foci of increased power Doppler flow detected by a radiologist were 4.7 times more likely to contain cancer than adjacent tissues without flow. CONCLUSION: Gray-scale and Doppler imaging did not reveal prostatic cancer with sufficient accuracy to avoid sextant biopsy. Power Doppler may be useful for targeted biopsies when the number of biopsy passes must be limited. There is benefit from increased operator experience with Doppler imaging, but there is no demonstrable benefit of power Doppler over conventional color Doppler sonography.     

Color Doppler sonography: its real role in the evaluation of children with highly suspected testicular torsion

The goal of this study was to assess the reliability of color Doppler imaging in boys who presented with acute scrotal pain and borderline clinical findings. The second purpose of the study was to evaluate the potential change in diagnostic accuracy as a result of employing radiological staff with varying levels of experience. Thirty-eight consecutive patients with highly suspected testicular torsion were enrolled in this prospective study. Clinical examination was followed by color Doppler US (7.5-MHz transducer). The staff of radiologists included four residents and three experienced radiologists. All patients underwent surgical exploration. All original reports of residents were reviewed by experienced radiologists and sensitivity with specificity were determined and compared. Original interpretations of color Doppler imaging yielded sensitivity of 77.8% and specificity of 85%, which changed after review to 88.9 and 90%, respectively. Clinical assessment was accurate only in 47.4%. Agreement between original and retrospective color Doppler diagnosis was obtained in 20 of 23 (86.9%) reviewed cases. Color Doppler US may prevent unnecessary surgery in the cases with conclusive normal and increased blood flow. In all other situations scrotal exploration should be performed.     

Diagnosis of acute appendicitis in pregnant women: value of sonography.

OBJECTIVE. The diagnosis of acute appendicitis in pregnant women often is difficult to make on the basis of clinical findings, and radiologic examination is limited because of the potentially hazardous effects of radiation. This study was done to assess the value of sonography in the diagnosis of acute appendicitis in pregnant women. SUBJECTS AND METHODS. We obtained sonograms in 45 pregnant women with clinically suspected acute appendicitis. Our sonographic technique included graded-compression scanning. The left lateral decubitus position was used in the third trimester of gestation. The sonographic criterion for the diagnosis of acute appendicitis was visualization of an incompressible appendix with a maximal diameter greater than 7 mm. We correlated the sonographic findings with the surgical findings in 22 cases and with the results of clinical follow-up in 23 cases. RESULTS. Sonography could not be used to make the diagnosis in three (7%) of 45 patients because the size of the gravid uterus prevented use of the graded-compression technique. These three patients were in the third trimester of pregnancy (greater than 35 weeks' gestation). Sonographic findings were used as a basis for diagnosis in 42 cases. Acute appendicitis was diagnosed on the basis of sonograms in 16 patients, and in all but one of these patients, acute appendicitis was confirmed by surgical and pathologic findings. In the 42 cases in which the imaging findings indicated the diagnosis, the overall sensitivity of sonography was 100%, the specificity was 96%, and the accuracy was 98%. CONCLUSION. Our experience suggests that graded-compression sonography is a valuable procedure for detecting acute appendicitis in pregnant women despite technical difficulty in performing it during the third trimester of pregnancy.     

High-frequency Doppler US of the prostate: effect of patient position

PURPOSE: To evaluate cancer detection with directed biopsy of the prostate on the basis of high-frequency Doppler ultrasonographic (US) findings, and to determine the effect of patient position on the observed flow pattern. MATERIALS AND METHODS: Thirty-two patients were evaluated in the left lateral decubitus position with gray-scale, color Doppler, and power Doppler transrectal US. Up to four directed biopsy specimens were obtained on the basis of gray-scale and Doppler US findings, and modified sextant biopsy followed. Analysis of variance and the Wilcoxon signed rank test were used to evaluate the distribution of Doppler signals within the prostate. Three healthy volunteers with no known prostate disease were also examined in supine and both decubitus positions. RESULTS: In the patient group, both color and power Doppler US demonstrated increased flow on the left side of the prostate, with greater flow toward the base of the gland (P <.002). Consequently, 62 of 90 directed-biopsy cores were obtained in the left base and mid-gland. The positive biopsy rate for directed biopsy was not significantly different from that of sextant biopsy (P =.4). Seven patients had cancer that was identified with sextant biopsy, but only four cancers were identified with directed biopsy. Each of the three healthy volunteers demonstrated increased Doppler flow on the dependent side when the subject was in the lateral decubitus position. CONCLUSION: The positive yield of directed biopsy was similar to the yield of sextant biopsy. On the basis of observations made in healthy volunteers, the authors conclude that flow asymmetry in patients who underwent biopsy may have been related to patient position.     

Sonographic appearance of nonoperatively treated Achilles tendon ruptures

Objective. This report describes the gray-scale and color Doppler sonographic appearance of healed Achilles tendon ruptures that have been treated nonoperatively. Design and patients. Eleven patients with acute Achilles tendon ruptures were studied with sonography in the acute setting and following nonoperative management of their torn tendon. Results. On sonographic examination, healed tendons treated nonoperatively are characterized by mild residual distortion of the normal fibrillar architecture of the tendon, anterior bulging or irregularity of the healed tendon, and a hypoechoic area about the site of rupture. Less frequent observations include mildly increased color flow and calcification at the rupture site. The previously described findings of acute tears, including hematomas, gaps at the rupture site, hyperemic torn tendon ends, and markedly distorted fibrillar architecture, were seen to have resolved in this series. Conclusion. The Achilles tendon tear treated nonoperatively has a different sonographic appearance from that of a normal or acutely ruptured tendon. Received: 24 November 1999 Revision requested: 23 January 2000 Revision received: 8 February 2000 Accepted: 8 February 2000     

Improved imaging of liver metastases with stimulated acoustic emission in the late phase of enhancement with the US contrast agent SH U 508A: early experience

PURPOSE: To see whether stimulated acoustic emission (SAE) in the liver parenchyma in the late phase of enhancement with SH U 508A increases the conspicuity of occult metastases at ultrasonography (US). MATERIALS AND METHODS: Eighteen patients with known hypo- or hypervascular hepatic metastases underwent US after SH U 508A administration, after a delay of at least 5 minutes, to ensure decay of blood pool enhancement. In 16 patients with visible metastases, conspicuity was compared on registered SAE and gray-scale scans by two blinded readers and by using computerized analysis of relative gray-scale and color Doppler conspicuity scores inside and outside the lesion. In nine patients, areas suspected of being involved but without definite gray-scale masses were imaged in the same way. Paired sections were analyzed by two blinded readers looking for parenchymal color defects without corresponding gray-scale masses; nine control images from three healthy volunteers were also included. RESULTS: Intense, transient parenchymal SAE was seen in all subjects. All metastases appeared as areas of reduced or absent signal. The conspicuity score was 80% for SAE versus 9% for gray-scale US (P < .001, Wilcoxon signed rank test). SAE-specific defects were seen in all patients but in none of the volunteers. Metastases seen on SAE but undetectable on gray-scale images were proved in three patients. CONCLUSION: SAE with SH U 508A improves the conspicuity of metastases. SAE-specific defects may reveal isoechoic or subtle metastases.     

Diagnostic efficacy of endovaginal color Doppler flow imaging in an ectopic pregnancy screening program.

The authors compared the diagnostic yield of endovaginal color and pulsed Doppler ultrasound (US) in conjunction with endovaginal sonography with that of endovaginal sonography alone in patients prescreened to be at increased risk for ectopic pregnancy. Pelvic structures were evaluated for overall vascularity and for the presence of characteristic pulsed Doppler US velocity waveforms. The diagnostic sensitivity of the initial endovaginal sonographic examination increased with the addition of color and pulsed Doppler US, from 71% to 87% for ectopic pregnancy, from 24% to 59% for failed intrauterine pregnancy, and from 90% to 99% for viable intrauterine pregnancy. Specificities for endovaginal sonography with color and pulsed Doppler US ranged from 99% to 100%. Use of endovaginal color and pulsed Doppler US increased the percentage of diagnostic initial sonographic examinations from 62% to 82%. The improved diagnostic sensitivity of endovaginal color Doppler US for ectopic pregnancy may ultimately result in earlier treatment, with reduced morbidity and mortality.