Sonography in a clinical algorithm for early evaluation of 1671 patients with blunt abdominal trauma

OBJECTIVE: The purpose of this study was to evaluate the efficacy of sonography in our algorithm when differentiating patients with blunt abdominal trauma who need immediate surgery from patients who would benefit from further diagnostic workup or who need no treatment. SUBJECTS AND METHODS: We performed abdominal sonography as the primary screening tool in 1671 consecutive patients in our prospective study. Radiologists performed sonography in the trauma room within minutes of the arrival of each patient. Hemodynamic instability in conjunction with positive sonographic findings led to emergency laparotomy. Otherwise, positive sonographic findings warranted additional diagnostic tests. Observing free fluid or organ injury caused us to categorize sonographic findings as positive. RESULTS: Sonography correctly identified all patients requiring emergency laparotomy. No inconclusive laparotomies were performed in this group. The sensitivity of sonography for revealing intraabdominal injury was 88%, the specificity was 100%, and the accuracy was 99%. In 132 patients (8%), abdominal CT was performed. CT revealed relevant posttraumatic abnormalities in 61% of all patients. Four hundred seventy patients with negative sonographic findings were discharged approximately 12 hr after admission; two of these patients (0.4%) were mistakenly discharged. Trauma scores did not influence the efficacy of sonography. CONCLUSION: Our algorithm that uses sonography as the primary diagnostic tool provides accurate, fast, cost-effective, and noninvasive initial management of patients with blunt abdominal trauma. Our test characteristics were excellent indicators of the need for emergency laparotomy. Sonography also achieves high values in revealing relevant injury. Our algorithm produced medically satisfactory and economically prudent management of patients with blunt abdominal trauma.     

急诊超声检查腹部创伤245例

目的探讨急诊超声在腹部创伤后定位诊断内脏损伤的价值.方法回顾分析急诊超声诊断并经手术或CT证实的腹部创伤所致内脏损伤245例.结果①245例共346个脏器损伤,超声确诊299例,误诊47例,总符合率为86.4%;②超声诊断脾、肝、肾及胃肠、肠系膜血管、膀胱、后腹膜脏器损伤等符合率分别为：93.4%、91.9%、80.9%及51.3%;③超声与手术比较检出腹腔积液及腹膜后血肿符合率分别为：100%（213/213）和89.5%（51/57）.结论急诊超声对腹部创伤后定位诊断脏器损伤具有较高临床诊断价值.     

Gastrointestinal lymphoma: sonographic findings in 54 patients

Between 1980 and 1990, 580 patients with known malignant lymphoma were referred for sonography for evaluation of abdominal masses as a part of the initial staging of the disease. In 54 patients, sonography showed different degrees of hypoechoic bowel wall thickening; gastrointestinal lymphoma was confirmed by histologic examination in all of these patients (non-Hodgkin lymphoma in 50, Hodgkin disease in four). Nineteen of the 54 patients had primary gastrointestinal lymphoma; the other 35 had widespread tumor with secondary gastrointestinal involvement. The portions of gastrointestinal tract involved included the stomach (38), small intestine (five), colon (seven), and multiple sites (four). Several sonographic patterns were found: 39 patients had circumferential involvement of the bowel wall, four had bulky tumors, and two had nodular extraluminal spread. Eight patients had segmental infiltration, and one had mucosal involvement. The results of this study indicate that sonography is of value for examining patients with gastrointestinal lymphoma and that several patterns of involvement can be detected.     

Pancreatic pseudocyst: comparative evaluation by sonography and computed tomography

Fifty-four patients were referred to rule out pancreatic pseudocyst. These patients underwent both sonographic and abdominal computed tomographic (CT) examinations for the evaluation of suspected pseudocysts. Among the 54 cases were 24 with proven pseudocysts. CT correctly identified 23 of the 24 pseudocysts with one false-negative and two false-positive studies. With sonography, the studies were technically inadequate in 20 of the 54 patients examined. Sonography correctly diagnosed 18 of the 24 pseudocysts; however, in 10 of these 18 cases sonographic findings were incomplete relative to CT findings. There were one false-negative and three false-positive sonographic studies. On the basis of this study, it was concluded that CT is more accurate than sonography in both diagnosing and demonstrating the extent of pseudocysts of the pancreas.     

Contrast-enhanced sonography for diagnosis of ruptured abdominal aortic aneurysm

OBJECTIVE: We describe the contrast-specific sonography features of ruptured abdominal aortic aneurysm, and we hypothesize that this technique would be useful for emergency imaging of patients with suspected aneurysm rupture. CONCLUSION: We used contrast-specific sonography to assess eight patients with ruptured abdominal aortic aneurysm. Five of these cases were correlated with CT findings. We found that contrast-enhanced sonography can reveal features specific for ruptured aortic aneurysm without causing a significant delay in surgery. This technique may be as effective as CT but may allow a more rapid and noninvasive diagnosis, especially when sonography can be performed bedside.     

Abdominal sonography in examination of children with blunt abdominal trauma

OBJECTIVE: The objective of our study was to evaluate abdominal sonography for the detection of fluid and organ injury in children with blunt abdominal trauma. SUBJECTS AND METHODS: Fifty-one consecutive children with blunt abdominal trauma requiring abdominal CT were prospectively examined with sonography. Sonograms and CTs were independently evaluated by two radiologists for fluid and organ injury; CT examinations were considered abnormal if either was identified. Differences in CT interpretation were settled by a third observer. Using CT as the truth standard, we calculated the sensitivity, specificity, and negative predictive value of sonography for both observers. Agreement of the sonographic interpretations was evaluated using kappa statistic. RESULTS: In 33.3% of patients, CT revealed fluid, organ injury, or both. The sensitivity and specificity of sonography when detection of fluid was the sole parameter evaluated was 58.8% and 79.4%, respectively, for observer 1 and 47.1% and 79.4%, respectively, for observer 2. In contrast, the sensitivity and specificity of sonography when detection of both fluid and organ injury was evaluated was 64.7% and 79.4%, respectively, for observer 1 and 70.6% and 70.6%, respectively, for observer 2. The negative predictive value of sonography was 79.4% and 75.0% with evaluation limited to detection of fluid and 81.8% and 82.8% with evaluation of fluid and organ abnormality for observers 1 and 2 , respectively. Agreement was excellent for sonographic identification of fluid (kappa = 0.82) but poor for detection of organ injury (kappa = 0.34). CONCLUSION: The low sensitivity and negative predictive value of sonography when assessing for either fluid alone or fluid and organ injury suggest that a normal screening sonography alone in the setting of blunt abdominal trauma fails to confidently exclude the presence of an intraabdominal injury.     

Comprehensive review of typical and atypical pathology of the appendix on CT: cases with clinical implications

Acute appendicitis is the most common abdominal surgical emergency in the United States with approximately 250,000 cases annually. Computed Tomography (CT) has emerged as the most accurate diagnostic test to triage these patients for emergent surgery. Although the radiology search pattern is prioritized to detect an inflamed appendix, not all appearances equate to a typical surgical appendicitis. There are a select set of atypical pathologies involving the appendix that have subtle differences on CT, but can have catastrophic complications if treated with emergent appendectomy. This paper will review the spectrum of CT appearances and clinical management for typical and atypical appendiceal pathologies.     

The relevance of free fluid between intestinal loops detected by sonography in the clinical assessment of small bowel obstruction in adults

INTRODUCTION: The main role of the radiologist in the management of patients with suspicion of small bowel obstruction is to help triage patients into those that need immediate surgical intervention from those that require medical therapy or delayed surgery. Ultrasound examination is usually considered not helpful in bowel obstruction because of air in the intestinal lumen that interferes the evaluation of the intestinal loops, however recently some Authors attested the increasing important role of sonography in the acute abdominal disease. Aim of our report is to demonstrate the value of free fluid detected by US in differentiating between low and high-grade small bowel obstruction. MATERIALS AND METHODS: The study is based on 742 consecutive patients who presented symptoms of the acute abdomen; all patients had undergone initial serial abdominal plain film and US examinations prior to any medical intervention. We reviewed the imaging findings of 150 cases in whom small bowel obstruction was clinically suspected and confirmed at surgery. We consider the following radiographic and US findings: dilatation of small bowel loops; bowel wall thickness; presence of air-fluid levels; thickness of valvulae conniventes; evidence of peristalsis; presence and echogenicity of extraluminal fluid. We looked at the value of extraluminal peritoneal fluid at US examination in differentiating low and high-grade small bowel obstruction based on the surgical outcome. RESULTS: In 46 patients altered peristaltic activity, thin bowel walls, fluid filled loops with hyperechoic spots in the bowel segment proximal to obstruction were noted at US, whereas radiographic features were: moderate dilatation of small bowel loops, with thin bowel wall and evidence of numerous and subtle valvulae conniventes; presence of air-fluid levels was also noted. In 70 other patients, US examination revealed all the findings described in the precedent cases and also the presence of free extraluminal fluid; abdominal plain film showed an increased dilatation of small bowel loops with moderate thickened wall and air-fluid levels. In 34 other patients US examination revealed the presence of thick-walled loops, hypoperistalsis and a larger amount of free extraluminal fluid. Radiographic findings in these patients were: horizontal featured and markedly dilated small bowel loops presenting parietal thickness, presence of intraluminal fluid stasis and evidence of thickened, sparse and incomplete valvulae conniventes. At surgery etiology of small bowel obstructions was various, but most of cases related to adhesions (70 cases). The presence of extraluminal fluid were confirmed at surgery in 104 patients. CONCLUSIONS: Our experience using sonography in suspicion of SBO (small bowel obstruction) suggests the usefulness of this imaging modality to differentiate a functional or obstructive ileus, demonstrating the evidence of intestinal peristalsis. Furthermore, the presence of a large amount of fluid between dilated small bowel loops suggests worsening mechanical small bowel obstruction, that requires not a medical therapy but immediate surgery.     

Suspected ureteral colic: primary helical CT versus selective helical CT after unenhanced radiography and sonography.

OBJECTIVE: The purpose of this study was to compare the accuracy of unenhanced helical CT with combined sonography and unenhanced radiography in patients with acute flank pain suggestive of ureteral colic. SUBJECTS AND METHODS: From January 1997 to December 1999, 181 consecutive patients with acute flank pain underwent unenhanced radiography, sonography, and unenhanced helical CT (protocol A). From January 2000 to December 2000, 96 consecutive patients arriving at the emergency department with acute flank pain were alternately submitted either to primary unenhanced helical CT (protocol B, 48 patients) or to unenhanced radiography and sonography with the addition of helical CT in unclear cases (protocol C, 48 patients). RESULTS: When compared with the diagnostic accuracy for ureterolithiasis of the combined sonography and radiography in the same group of subjects (protocol A), CT had a greater sensitivity (92% vs 77%), negative predictive value (87% vs 68%), and overall accuracy (94% vs 83%). Among patients who underwent primary CT (protocol B), we found three false-negatives (all with spontaneous stone passage) and no false-positives. Among patients initially examined with unenhanced radiography and sonography (protocol C), we found one false-positive (leading to patient admission and needless repeated radiographic and sonographic studies) and six false-negatives (all followed by an uncomplicated course and spontaneous passage); CT depicted four of these stones but did not result in change in treatment. Fourteen percent of the patients in protocol C required invasive treatment, but combined sonography and radiography showed stones and hydronephrosis in all these patients. CONCLUSION: Unenhanced CT was the most accurate modality for determining the presence of ureterolithiasis. The combination of abdominal radiography and sonography, however, yielded comparable results with no clinically important misdiagnoses and thus can be used as an alternative when CT resources are limited.     

The role of early sonography in the management of the acute abdomen

A prospective study was set up in a busy teaching hospital to evaluate the role of a 24 h emergency ultrasonography service in patients presenting with acute abdominal pain. Seventy-five patients due for admission via the accident and emergency department with acute onset of upper or lower abdominal pain were imaged at the request of our surgical colleagues. In 14 patients (18.7%), a diagnosis was made up by sonographic examination which had not been clinically expected. Twelve of this group were female with gynaecological pathology and all 14 had their proposed emergency surgery deferred following the sonographic examination. In 26 patients (34.7%), sonography confirmed the first diagnosis suspected clinically and in nine cases (12%) confirmed the second or third differential diagnosis. Sonography made no contribution to the diagnosis in 24 patients (32%) and in two cases (2.6%) was considered misleading. The results of this study demonstrate that emergency ultrasonography is most useful in the diagnosis of female patients presenting with mid to lower abdominal pain.     

Closed-loop obstruction of the small bowel: CT and sonographic appearance

Two patients with closed loop obstruction diagnosed by CT and sonography are reported. Abdominal radiograph was nonspecific. The characteristic CT and sonographic features included (a) isolated conglomerate of dilated, fluid-filled bowel loops; (b) fixation of these "U" shaped distended loops; (c) thickened bowel wall; and (d) extraluminal fluid.     

Sonographic characterization of carotid plaque: detection of hemorrhage

By careful evaluation of the sonographic characteristics of carotid plaques, two patterns can be identified: a homogeneous pattern containing uniform echoes corresponding to dense fibrous tissue and a heterogeneous pattern containing mixed echoes and anechoic areas that represent intraplaque hemorrhage pathologically. A prospective study was conducted of 50 patients to determine the accuracy of identifying these different forms of plaque. The patients' carotid arteries were examined by a high-resolution duplex scanner before carotid endarterectomy. The plaques were evaluated carefully by vascular surgeons and pathologists for the presence of intraplaque hemorrhage. In this study, the accuracy of identifying the presence or absence of intraplaque hemorrhage with sonography was 90% (48 of 54); sensitivity, 94% (17 of 18); and specificity, 88% (27 of 31). High-resolution sonography appears to be an accurate means of identifying intraplaque hemorrhage and may ultimately be useful in identifying patients at risk for embolic disease.     

Role of abdominal sonography in excluding abdominal malignancy in the initial workup of patients with abdominal complaints.

OBJECTIVE: The objective of this study was to evaluate the diagnostic performance and role of abdominal sonography in excluding abdominal malignancy in the initial workup of patients with abdominal complaints. MATERIALS AND METHODS: The sonographic report and follow-up data of 494 patients who had undergone a primary sonographic examination were retrospectively reviewed. Sensitivity and specificity of sonography for the diagnosis of an abdominal malignancy-that is, a primary tumor or metastasis-were determined. Multivariate logistic regression analysis was performed to determine the incremental value of sonography, and a prediction rule was derived. RESULTS: An abnormality on sonography--that is, a mass, ascites, pleural effusion, hydronephrosis, or focal intraparenchymal heterogeneity suggestive of a mass--had a sensitivity for abdominal malignancy of 86% and a specificity of 94%. In the multivariate analysis, the sonographic findings were found to have significant incremental value (odds ratio = 74) after adjustment for the clinical determinants. In patients younger than 38 years with no previous malignancy, no palpable mass, normal liver function test results, and negative findings on sonographic examination, the risk of an abdominal malignancy was less than 1 in 500. CONCLUSION: Our results suggest that sonography may be useful in excluding an abdominal malignancy when used in a primary care setting in patients with abdominal complaints who are at low risk for a malignancy.     

Sonographic demonstration of intestinal involvement in Henoch-Schönlein syndrome

We evaluated the efficacy of intestinal sonography in the diagnosis of gastrointestinal involvement of Henoch-Schönlein syndrome (HSS). Intestinal sonography was performed in 20 children who were clinically diagnosed as HSS and sonographic findings of the intestinal system were reviewed. Out of 20 patients, 10 who suffered from abdominal pain demonstrated sonographic findings consistent with small intestinal involvement (dilatation of intestinal segments, hypomotility, and eccentric thickening of the intestinal wall). Our results reveal that sonography of the intestine may be useful in the evaluation of the involvement of HSS.     

Small bowell volvulus - combined radiological findings]

PURPOSE: We retrospectively evaluated the radiological findings observed at plain abdominal film, abdominal sonography and abdominal CT performed in 66 patients with surgically proven small bowel volvulus. MATERIAL AND METHODS: Sixty-six patients (35 women and 31 men, ranging in age 38-77 years) with surgically proven small bowel volvulus were submitted to plain film, sonography and CT of the abdomen. Abdominal plain film was performed in the upright position (postero-anterior view) in 46 cases, and in the supine position in 20 cases. On plain abdominal film we evaluated the following findings: bowel loops dilatation, air-fluid levels and site of obstruction. At abdominal US, performed with 3.5 e 7.5 MHz probes, we retrospectively searched for: bowel loop dilatation, bowel wall thickening, peristalsis alteration, extraluminal fluid. CT was performed with a helical unit (thickness 4 mm, reconstruction interval 4 mm, pitch 1.5), after intravenous contrast agent (120 ml) infusion (3 ml/s, 55 s acquisition delay from bolus starting) and using a power injector. The following CT findings were searched for: whirl sign, beak sign, extraluminal fluid, bowel loop dilatation, bowel wall thickening, bowel wall or mesenteric alterations. RESULTS: Plain abdominal film showed the following findings: air-fluid levels (92.4% of cases), bowel loops dilatation (71.2%), site of obstruction (42.4%). Abdominal sonography demonstrated bowel loop dilatation (48.5%), extraluminal fluid (48.5%), peristalsis alteration (27.3%), bowel wall thickening (27.3%). The most frequent CT findings were: bowel loop dilatation (95.5%), bowel wall thickening (78.8%), beak sign (69.7%), mesenteric alterations (66.7%), extraluminal fluid (54.5%), whirl sign (13.6%). CONCLUSIONS: Air-fluid levels and bowel loop dilatation were the most frequent radiological findings in our series. Plain abdominal film allowed us to identify signs of obstruction, whereas signs of bowel wall necrosis were accurately shown by abdominal CT.     

Successful Emergency Stenting of Acute Ruptured False Iliac Aneurysm

A 75-year-old man complaining of acute abdominal pain, 1 month after elective surgical repair of an abdominal aortic aneurysm by an aortabi-iliac bypass graft, was referred and admitted to the emergency room. Imaging by sonography and computed tomography scan revealed a ruptured iliac pseudoaneurysm at the right iliac anastomotic site with associated large retroperitoneal hematoma. We inserted a self-expanding covered Z-stent graft by a transfemoral approach and the iliac anastomotic pseudoaneurysm was successfully excluded. Our case demonstrates the possibilities of an endovascular approach for providing a fast, efficient and less aggravating procedure in order to treat these life-threatening conditions.     

Comparison of sonography and plain films in evaluation of the acute abdomen

In 95 patients with acute abdominal pain seen in the emergency ward of a large urban teaching hospital, real-time sonography was performed in conjunction with a plain film of the abdomen in order to detect what, if any, added information was provided by the sonographic examination. In 20 patients (21%) the sonogram contributed important diagnostic information not provided by the plain film of the abdomen. Most of these patients had pathology referable to the biliary tract (14 of 20). In 28 patients (30%), the sonogram confirmed the diagnosis by abdominal film. In 39 (41%) the sonogram added no relevant information, and in three (3%) it was deleterious. In five (5%) the plain film provided more information than the sonogram.     

The role of sonography in abdominal trauma: The European experience

Abdominal trauma may be a life-threatening entity. Whereas computed tomography (CT) seems to be the major noninvasive diagnostic tool for evaluation of abdominal trauma in the United States, sonography is the modality of first choice in the majority of European hospitals. Sonography has replaced diagnostic peritoneal lavage for detecting or excluding intraperitoneal free blood. We advocate sonography for any polytrauma patient in the trauma emergency room (TER), because it is a quickly performed, repeatable, and inexpensive imaging modality, serving as a decision-maker in the TER and enabling the avoidance of unnecessary CT. We strongly believe that radiologists should make full use of the potential of ultrasound in the TER. Radiologists should have access to, and experience with, CT as well as sonography, allowing an unbiased decision as to which modality is adequate to answer the specific questions raised by different trauma patients. This article defines the role of sonography in the TER and compares it with CT.     

Incidental findings on gallbladder sonography

Upper abdominal ultrasonography demonstrated important incidental findings in 4.4% of 480 patients referred specifically for a gallbladder examination. The sonographic findings contributed dramatically to the subsequent management of these patients. A policy of examining all of the upper abdominal organs is advocated in all patients referred for sonography of a single organ or system.     

Safety and efficacy of a new oral contrast agent for sonography: a phase II trial.

OBJECTIVE: Our purpose was to study the safety and efficacy of a new orally administered sonographic contrast agent in patients with suspected upper abdominal disorders. SUBJECTS AND METHODS: Ninety-nine patients with signs or symptoms suggestive of upper abdominal disorders were enrolled in a prospective range-of-dose phase II clinical trial at six sites; sonograms of 93 patients were evaluated for efficacy. Patients underwent upper abdominal sonography before and after receiving a randomized dose of the contrast agent (200, 400, 600, 800, or 1000 ml). Safety was monitored by physical examination and laboratory testing. The primary efficacy parameter was additional information provided by the contrast agent when comparing unenhanced and contrast-enhanced sonography. RESULTS: Of the 14 adverse events in 11 patients, only five, which included mild diarrhea and nausea, were considered related to the contrast agent. In 83 of 93 patients, additional information was obtained from the contrast-enhanced images. Visualization of anatomy was improved as follows: the stomach, in 82% of patients; the duodenum, in 63% of patients; the pancreatic head and body, in 61% of patients; and the pancreatic tail, in 67% of patients. CONCLUSION: SonoRx is a safe and well-tolerated contrast agent that improves the sonographic evaluation of the upper abdomen, with significant improvement in imaging the stomach, duodenum, and pancreas.