Accuracy of nonfocused helical CT for the diagnosis of acute appendicitis: a 5-year review

OBJECTIVE: The clinical usefulness of routine, nonfocused helical CT was evaluated in diagnosing acute appendicitis or providing an alternative diagnosis in patients presenting to the emergency department with acute lower abdominal pain. MATERIALS AND METHODS: We reviewed CT reports and clinical records of 650 consecutive adult patients who presented between January 1996 and December 2000 with right lower quadrant pain or lower abdominal pain and clinical findings suggestive of appendicitis. Helical CT was performed with oral contrast material in 610 cases (93.8%) and IV contrast in 572 cases (88.0%). Both vascular and enteric contrast media were administered in 544 cases (83.7%). Rectal contrast material was administered in 52 cases (8.0%). The abdomen was helically scanned from the dome of the diaphragm to the iliac crests with a collimation of 7 mm, from the iliac crests to the acetabular roof at a 5-mm collimation, from the acetabular roof to the symphysis pubis with a collimation of 5-10 mm. The surgical or clinical record was used for follow-up. RESULTS: Of the 650 patients, 552 (84.9%) had adequate clinical follow-up. There were 137 true-positive, eight false-positive, five false-negative, and 402 true-negative cases. The sensitivity, specificity, and accuracy of nonfocused helical CT were 96.5%, 98.0%, 97.6%, respectively. The positive and negative predictive values were 94.5% and 98.8%, respectively. In patients without acute appendicitis, CT suggested an alternative diagnosis, which clinically explained the patient's acute abdominal pain in 266 patients (66.2%). CONCLUSION: Nonfocused helical CT was highly accurate in diagnosing acute appendicitis or suggesting an alternative diagnosis in patients with acute lower abdominal pain or right lower quadrant pain.     

高龄阑尾炎病情严重程度诊断分析

目的探讨与比较老年急性单纯性阑尾炎与急性化脓性阑尾炎、坏疽阑尾炎或伴穿孔的发病特点、诊断要点、治疗方法选择。方法选取近10年我院符合急诊初诊为急性阑尾炎,年龄在70岁以上的高龄患者,共79例,按照标准,根据炎性反应轻重分两组,从术前症状、体征、相关检验、检查进行统计学比较。结果 77例为非手术治疗或手术治疗后急性阑尾炎痊愈患者,行手术治疗患者,经病理证实诊断明确;2例为回盲部肿瘤患者,手术病理明确诊断。结论体温升高、右下腹反跳痛、超声诊断对于区分高龄阑尾炎严重程度具有较大意义,转移性右下腹痛和血象升高也有一定参考意义。同时应当注意同回盲部肿瘤相鉴别。     

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.     

小儿腹痛84例的超声诊断分析

目的探讨超声对小儿腹痛的诊断价值。方法回顾性分析84例以腹痛为主要症状的患儿超声声像图特点，比较不同疾病患儿超声表现的差异性。结果84例患儿中，超声诊断为肠系膜淋巴结炎34例，急性阑尾炎13例，诊断准确率100％；肠痉挛21例；肠系膜淋巴结结核4例，1例伴有结核性腹膜炎：肠套叠2例；淋巴瘤1例；9例B超下未发现阳性声像图表现，随访最后诊断为慢性胃炎6例，肠道蛔虫病2例，慢性阑尾炎1例。结论超声检查诊断小儿腹痛准确性较高，可以大大减少临床上诊断及治疗的盲目性，值得推广应用。     

儿内科急性阑尾炎诊治探讨

目的 探讨儿内科小儿急性阑尾炎的诊治特点。方法 对儿内科就诊的79例急性阑尾炎病例进行回顾性分析。结果 首次于儿内科就诊的79例急性阑尾炎病儿，均于就诊后24h内转入儿外科治疗，临床以腹痛、发热、末梢血白细胞及中性粒细胞增高为主要表现。74例经手术治疗后证实为急性阑尾炎，其中化脓性阑尾炎45例，坏疽性阑尾炎12例，蛔虫性阑尾炎1例，单纯性阑尾炎16例。36例发生阑尾穿孔，21例并发弥漫性腹膜炎。5例未手术治疗。结论 首次于儿科内科就诊的腹痛患儿，伴有发热、周围血白细胞或／和中性粒细胞增高，尤其有右下腹固定压痛者，鉴别除外儿内科常见腹痛性疾病，应考虑阑尾炎，并及时与儿外科医生联系，早期诊断，及时处理，减少并发症。     

Alternative diagnoses of acute appendicitis on helical CT with intravenous and rectal contrast

At our institution, helical CT of the abdomen and pelvis with intravenous and rectal contrast (CTRC) has become the modality of choice for investigation of patients with right lower quadrant pain and clinical suspicion of acute appendicitis. CTRC has proven useful for the diagnosis of acute appendicitis (AA) and at the same time identifies alternative diagnoses mimicking AA. This pictorial assay illustrates the imaging findings of AA and its mimickers including primary epiploic appendagitis, right-sided diverticulitis, torsion of Meckel's diverticulum, gynecologic disorders, obstructive uropathy, right lower lobe pneumonia, and other conditions.     

The nonvisualized appendix: incidence of acute appendicitis when secondary inflammatory changes are absent

OBJECTIVE: The objective of our study was to assess the importance of nonvisualization of the appendix and its association with acute appendicitis on helical CT when secondary inflammatory changes are absent. MATERIALS AND METHODS: After we received institutional review board approval, CT scans of 366 consecutive patients obtained for lower abdominal or right lower quadrant pain and to rule out appendicitis were retrospectively reviewed. Images were reviewed by an experienced abdominal radiologist and compared with the formal interpretation. The amount of right lower quadrant and pericecal fat was quantified on a scale of 0 (none) to 2 (abundant). Patients with a nonvisualized appendix and other findings compatible with acute appendicitis-such as abscess formation, localized perforation, periappendiceal fat stranding, or appendicolith-were excluded. RESULTS: The appendix could not be visualized by both reviewers in 46 (13%) of 366 cases. CT findings indicated another cause for the patient's symptoms in 12 cases (26%), including gastrointestinal and genitourinary processes. An alternate diagnosis was subsequently reached in 11 additional patients (24%) with follow-up imaging or clinical evaluation. Only one patient (2%) with a nonvisualized appendix had acute appendicitis, proven by surgical pathology. In this patient, there was paucity of fat in the right lower quadrant. CONCLUSION: In the absence of a distinctly visualized appendix and secondary inflammatory changes, the incidence of acute appendicitis is low. Nonvisualization of the appendix even when a small amount of fat is present in the right lower quadrant may safely exclude acute appendicitis if no secondary CT findings are present.     

Appendiceal hyperemia and/or distention is not always appendicitis: appendicitis mimicry in the pediatric population

Appendicitis is the most common surgical cause of acute abdominal pain in the pediatric population. Several conditions can mimic the clinical presentation of appendicitis, leaving imaging as an essential modality to uncover the etiology, yet under certain circumstances, it can be misleading. Here, we present three cases where findings on multidetector computerized tomography scans supported the diagnosis of appendicitis, yet an alternate cause was found. These cases highlight a particular pitfall of satisfaction of search.     

Accuracy of ultrasonography in acute right lower quadrant problems in children

The ultrasonographic findings in 139 consecutive children examined for right lower quadrant pain were prospectively documented. The following diagnoses were offered: (1) normal, (2) appendicitis, (3) mesenteric adenitis-enteritis, (4) adnexal problems, and (5) other. These diagnoses were then compared to the final operative or nonoperative clinical diagnoses in each case and overall percent accuracy was determined. The overall percent accuracy was 98 %, and with this result ultrasound of the acute abdomen, especially the right lower quadrant, can be placed into the forefront of primary care imaging of patients with right lower quadrant pain. Ultrasound provides more useful information, quicker, and more consistently than do clinical or laboratory evaluations. Consideration should be given to the performance of this study early in the work-up of these patients.     

Clinical and imaging mimickers of acute appendicitis in the pediatric population

OBJECTIVE: The purpose of this article is to present the imaging appearance of common mimickers of appendicitis in children with right lower quadrant pain. CONCLUSION: The majority of children who undergo imaging for suspected appendicitis will end up having an alternative diagnosis. These mimickers can be gastrointestinal, genitourinary, or pulmonary. Familiarity with these alternative diagnoses can aid in the challenging task of imaging right lower quadrant pain in the pediatric population.     

The echographic diagnosis of acute appendicitis and its complications

The authors report their experience with emergency US in patients hospitalized for clinical suspicion of acute appendicitis or presenting with pain in the right lower abdominal quadrant. One hundred fifty-two patients were examined with US: 93/152 had pathologies of the right iliac region; 81 of them underwent surgery (50/81 appendectomies). In 27 of these patients the inflamed appendix presented with a typical US pattern. All of them had surgical confirmation. In 13/50 cases, US findings followed an atypical pattern (6 patients had a periappendiceal mass in the right iliac region, 3 had small amounts of fluid in the Douglas pouch, and 4 had gas-filled bowel loops of the ileum). The false negatives were 10/50. US sensitivity was 80%, and its specificity was 54%. The most common pathologic conditions are described whose symptoms mimic those of acute appendicitis. US role in inflamed acute appendicitis is still to be defined. Nonetheless, the authors suggest that US be performed on all patients with atypical pain in the lower abdominal quadrants, because of its high diagnostic accuracy in many common pathologies mimicking appendicitis, especially urinary and uterine adnexal pathologies.     

Mesenteric adenitis-acute ileitis: A constellation of findings definable with ultrasound

We present the ultrasonographic findings in 45 pediatric patients referred to us for acute abdominal pain mimicking appendicitis. All of the patients demonstrated right lower quadrant or para-aortic tender adenopathy consistent with the diagnosis of mesenteric adenitis, but in addition, many of the patients demonstrated other findings, including intestinal hyperperistalsis, small bowel (jejunal and ileal) mucosal thickening (both circumferential and nodular), mesenteric thickening around the nodes, fluid-filled loops of intestine, a visible appendix which was often fluid filled, free fluid, a right lower quadrant mass, and cecal involvement. These diverse findings suggest that mesenteric adenitis need not be limited to adenopathy and ileocolitis in the right lower quadrant. These additional findings are helpful in differentiating mesenteric adenitis from appendicitis, even in those patients in whom a fluid-filled appendix is visualized.     

Isolated infarction of the cecum: CT findings in two patients

Colonic ischemia isolated to the cecum is a rare entity. The authors evaluated two patients who underwent computed tomography (CT) because appendicitis was suspected at clinical examination. CT findings were suggestive of isolated cecal ischemia or infarction. Surgical-histopathologic findings helped confirm the presumptive CT diagnoses. Isolated cecal infarction should be included in the differential diagnosis of acute right lower quadrant pain.     

A comparison of the Accuracy of Ultrasound and Computed Tomography in common diagnoses causing acute abdominal pain

Objectives

Head-to-head comparison of ultrasound and CT accuracy in common diagnoses causing acute abdominal pain.

Materials and methods

Consecutive patients with abdominal pain for >2 h and <5 days referred for imaging underwent both US and CT by different radiologists/radiological residents. An expert panel assigned a final diagnosis. Ultrasound and CT sensitivity and predictive values were calculated for frequent final diagnoses. Effect of patient characteristics and observer experience on ultrasound sensitivity was studied.

Results

Frequent final diagnoses in the 1,021 patients (mean age 47; 55% female) were appendicitis (284; 28%), diverticulitis (118; 12%) and cholecystitis (52; 5%). The sensitivity of CT in detecting appendicitis and diverticulitis was significantly higher than that of ultrasound: 94% versus 76% (p?p?=?0.048), respectively. For cholecystitis, the sensitivity of both was 73% (p?=?1.00). Positive predictive values did not differ significantly between ultrasound and CT for these conditions. Ultrasound sensitivity in detecting appendicitis and diverticulitis was not significantly negatively affected by patient characteristics or reader experience.

Conclusion

CT misses fewer cases than ultrasound, but both ultrasound and CT can reliably detect common diagnoses causing acute abdominal pain. Ultrasound sensitivity was largely not influenced by patient characteristics and reader experience.     

Ultrasound of acute GI tract conditions

Patients with acute abdominal pain are a great challenge to the radiologist. The clinical diagnosis is classically unreliable, resulting in both negative laparotomies as well as ill-advised surgical delay in a large number of patients. Ultrasound offers a non-invasive way to decrease both false-negative and false-positive diagnoses in this category of patients. This article focuses on the role of sonography in the diagnosis of acute conditions of the gastrointestinal tract tract such as appendicitis, sigmoid diverticulitis, Crohn's disease, colitis, infectious ileocecitis caused by Yersinia, Campylobacter or Salmonella, right-sided colonic diverticulitis, bowel malignancy presenting acutely, small bowel obstruction, intussusception, omental infarction, and epiploic appendagitis. The sonographic spectrum of these conditions as well as possible pitfalls are discussed using illustrative case histories.     

Acute epiploic appendagitis: CT findings in 33 cases

Acute epiploic appendagitis (AEA) is a benign self-limiting process presenting with acute abdominal pain often misdiagnosed clinically as either diverticulitis or appendicitis, but which has a pathognomonic CT appearance. The CT findings in 33 adult patients diagnosed by CT over a 33-month period as having AEA were retrospectively reviewed. The study group included 24 men and 9 women, with a mean age of 44.6 years. The mean age of the male patients was lower than that of the female patients, 40.9 vs 54.7 years. All patients presented with acute abdominal pain, mainly in the left (n=21) and right (n=9) lower quadrants, with localized tenderness in all patients and peritoneal irritation in 15 of them. Low-grade fever was found in 8 patients and mild leukocytosis in 16. Characteristic CT findings of an oval fatty mass with central streaky densities and surrounded by mesenteric stranding adjacent to the serosal surface of the colon were seen in all cases. Additional findings included mural thickening of the juxtaposed colon in 16 patients and peritoneal fluid in 7. One patient underwent surgery on the basis of an erroneous diagnosis of acute appendicitis. As CT is often used nowadays to evaluate various acute abdominal complaints, it may be the first imaging modality by which AEA is diagnosed. AEA should be included in the differential diagnosis in young male patients with localized left lower abdominal pain and tenderness. Electronic Publication     

Appendicitis in children: color Doppler sonography.

The authors used color Doppler ultrasonography (US) to evaluate 33 children with suspected appendicitis and found locally increased blood flow in all of 10 patients with appendicitis or periappendiceal abscess; the studies were normal in 16 patients without appendicitis. The gray-scale sonographic results were concordant in all 26 of these patients. In two other patients with presumptive mesenteric adenitis and in one patient with a hemorrhagic ovarian cyst at gray-scale US, color Doppler imaging showed no increased perfusion and aided in confirming the absence of a significant inflammatory process. In four other children, color Doppler US clarified gray-scale sonographic findings that might have been confused with complicated appendicitis and aided in the diagnosis of other causes of acute abdominal pain. These findings indicate that color Doppler US is a useful adjunct to gray-scale US in evaluating children with suspected acute appendicitis.     

Acute appendicitis, echographic findings

A case of acute appendicitis in which an appendicolith was present is described. The diagnosis was made by plain abdominal radiography and ultrasound, and was confirmed at surgery. The plain abdominal film showed a lamellated, round calcification, projecting over the right iliac wing. Ultrasound revealed a tubular, hypoechogenic structure, containing an oval hyperechogenic area with acoustic shadow. The recent literature was reviewed, and the "graded compression" technique is described. A summary is given of the ultrasound findings of acute appendicitis, and of its most important differential diagnoses in childhood: mesenterial adenitis, and--less frequently--terminal ileitis.     

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.     

Role of multidetector computed tomography (MDCT) in diagnosis of subhepatic appendicitis

Background

Acute appendicitis is a common surgical condition that is usually managed with early surgery, and is associated with low morbidity and mortality. However, some patients may have atypical symptoms and physical findings that may lead to a delay in diagnosis and increased complications.Ascending subhepatic appendicitis presenting with right upper abdominal pain may be clinically indistinguishable from acute pathology in the gallbladder, liver, biliary tree, right kidney and right urinary tract.

Aim of the work

To study the role of multidetector computed tomography in diagnosis of subhepatic appendicitis.

Subjects & methods

In the current study, we included fifteen patients diagnosed radiologically and confirmed surgically as subhepatic appendicitis.Ultrasonography followed by multidetector computed tomographic examination were performed to all patients before surgery.

Results

The clinical diagnosis of the patients included in this study at presentation was acute cholecystitis in four patients, pyelonephritis in three, and ureteric colic in three. Five patients were referred with uncertain diagnosis.The presence of subhepatic appendicitis was confirmed sonographically only in two patients. Computed tomography (CT) identified correctly subhepatic appendicitis in all cases.

Conclusion

Our study indicates the usefulness of multidetector CT in diagnosing atypical ascending subhepatic appendicitis.