Appendiceal and peri-appendiceal air at CT: prevalence, appearance and clinical significance

AIM: Appendiceal air has been reported as both a sign of appendicitis and of a normal appendix both at plain radiography and computed tomography (CT). It is the aim of this investigation to determine the prevalence, range of appearances, and significance of appendiceal and peri-appendiceal air at CT. PATIENTS AND METHODS: Appendiceal CT scans of 100 patients with proven appendicitis and 100 patients with a normal appendix were reviewed for the presence of appendiceal and peri-appendiceal air. All cases were correlated with surgical and pathological findings or clinical follow-up. RESULTS: In 100 CT cases of appendicitis, appendiceal and/or peri-appendiceal air was present in one or more forms in 31% of cases. When present, it appeared as intraluminal air bubbles (38.7%) or air-fluid levels (22.6%), appendolith air (41.9%), intramural air (16.1%), peri-appendiceal air bubbles (12.9%), or extraluminal air-fluid level(s) (29.0%). Intramural and extraluminal air correlated with perforation in 60% and 100%, respectively. In 100 CT cases of a normal appendix, air was present in 57%. It was always intraluminal and appeared as small bubbles of air (52.6%), a tubular-shaped air collection (43.9%), or as an air-fluid level (3.5%). The appendiceal lumen was either airless (43%), or minimally (32%), moderately (18%), or completely filled with air (7%). CONCLUSION: Air is a common finding at appendiceal CT in both the normal and inflamed appendix. Intraluminal air is seen in both appendicitis and normal appendices, and cannot be presumed to indicate a patent lumen and thus a normal appendix. Appendolith, intramural and peri-appendiceal air appear diagnostic of appendicitis.     

Resolution of late potentials with improvement in left ventricular systolic function in patients with first acute myocardial infarction

BACKGROUND: Little has been written about the use of computed tomography (CT) in the evaluation of small bowel obstruction (SBO) in children. The purpose of this study is to review the CT findings of SBO in a pediatric series and to increase awareness of CT as potential problem-solving tool for SBO in children. METHODS: The medical, surgical, radiographic, and CT scan records of 20 consecutive children with surgically proven SBO were retrospectively reviewed. Duodenal and neonatal obstruction was excluded. CT scans were evaluated for small and large bowel caliber, bowel wall thickening, the appearance of the mesentery, extraluminal abnormalities, and the ability to detect the cause of obstruction. RESULTS: Causes of obstruction included adhesions (nine), small bowel intussusception (four), abscess (two), segmental volvulus (two), Crohn disease (one), focal stricture (one), and internal hernia (one). Small bowel dilatation was present in 19/20 children. Small bowel caliber transition was noted in 17/19 children. Two children with no small bowel caliber transition had a collapsed colon. The colon appeared normal in caliber in nine children, collapsed in nine, and filled with stool proximally and collapsed distally in two. Small bowel thickening was present in six children and mesenteric venous engorgement in three. Specific causes of obstruction were identified on CT in nine children (45%) and could be correctly predicted in seven of nine children with adhesions. In four children, the causes were either not evident or alternate diagnoses could be made. CONCLUSION: CT can be a useful adjunct in evaluating the presence or causes of SBO in children.     

Acute graft-versus-host disease in children: abdominal CT findings

PURPOSE: To review the computed tomographic (CT) appearance of acute gastrointestinal graft-versus-host disease (GVHD) in children. MATERIALS AND METHODS: Sixteen abdominal CT scans obtained in 12 children with acute gastrointestinal GVHD who underwent allogeneic bone marrow transplantation (BMT) were compared with 16 CT scans obtained in autologous bone marrow recipients not at risk for GVHD (control group). Autopsy findings in six patients with GVHD were compared with CT findings. RESULTS: All CT scans in patients with GVHD showed an abnormally enhanced, thin mucosal layer of bowel wall involving fluid-filled, dilated, poorly opacified bowel loops from the duodenum to the rectum. This corresponded histologically to mucosal destruction and replacement by a thin layer of highly vascular granulation tissue. Bowel wall thickening was often absent. Infiltration of mesenteric fat was seen in 91% of patients The control group showed no similar abnormalities. CONCLUSION: Acute gastrointestinal GVHD characteristically appears on CT scans as multiple, diffuse, fluid-filled bowel loops with a thin, enhancing layer of bowel wall mucosa. Bowel wall thickening often is absent.     

Menstrual cycle and age: influence on parenchymal contrast medium enhancement in MR imaging of the breast

PURPOSE: To quantify how frequently mesenteric adenitis clinically mimics appendicitis and to determine its appearance at computed tomography (CT). MATERIALS AND METHODS: The medical records of 651 consecutive patients with an admission diagnosis of appendicitis were reviewed to determine how often mesenteric adenitis was the discharge diagnosis. The CT scans of a separate group of 18 patients with a discharge diagnosis of mesenteric adenitis were reviewed. These patients were part of a group of 100 consecutive patients prospectively evaluated with CT of the appendix for clinically suspected appendicitis. RESULTS: Fifty of 651 patients (7.7%) with an admission diagnosis of appendicitis had a discharge diagnosis of mesenteric adenitis. Mesenteric adenitis constituted 50 of the 252 (19.8%) discharge diagnoses other than appendicitis. All 18 CT scans of mesenteric adenitis showed three or more nodes that measured at least 5 mm in shortest axis clustered in the right lower quadrant, with a normal appendix identified. Eight patients had associated ileal or ileocecal wall thickening. CONCLUSION: Mesenteric adenitis is an important clinical mimic of appendicitis. It appears at CT as clustered, enlarged mesenteric lymph nodes with a normal appendix, and there may be associated ileitis or ileocolitis noted.     

Bronchiolitis obliterans syndrome: thin-section CT diagnosis of obstructive changes in infants and young children after lung transplantation

PURPOSE: To characterize the thin-section computed tomographic (CT) appearance of bronchiolitis fibrosa obliterans syndrome in infants and young children after lung transplantation. MATERIALS AND METHODS: Thin-section CT studies in six patients with bronchiolitis obliterans syndrome (age range, 2 months to 5 1/2 years) and in 15 control patients without obstructive airway disease (age range, 2 months to 7 years) who underwent bilateral lung transplantation were retrospectively reviewed. The thin-section CT scans were obtained during quiet sleep at a median of 24 months (range, 6-36 months) after transplantation. The CT studies were evaluated for mosaic perfusion, bronchial dilatation, bronchial wall thickening, and mucous plugging Final diagnoses in all patients were based pulmonary function test results. RESULTS: Thin-section CT findings in the six patients with clinically proved bronchiolitis obliterans syndrome were mosaic perfusion in five (83%) bronchial dilation in three (50%), and bronchial wall thickening in one (17%). Of the 15 control patients with normal pulmonary function test results, six (40%) had mosaic perfusion; none had bronchial dilatation or bronchial wall thickening. Mucous plugging was not seen in either group. Only the association of bronchial dilatation with bronchiolitis obliterans syndrome was significant (P = .02). CONCLUSION: Infants and young children with bronchiolitis obliterans syndrome after lung transplantation are more likely to have CT abnormalities than those with normal pulmonary function test results.     

Autocatalytic processing of pro-papaya proteinase IV is prevented by crowding of the active-site cleft

BACKGROUND: To establish the value of saline-filled appendiceal ultrasonography in the the diagnosis of clinically equivocal acute appendicitis. METHODS: Saline-filled ultrasonography was performed in 43 patients with an equivocal clinical diagnosis of acute appendicitis. RESULTS: Sonography diagnosed 31 of 32 patients without acute appendicitis (97%). A normal appendix was visualized in 15 patients (47%), and we identified a normal appendix in 15 of 22 patients (68%) in whom the colon was cleansed with Golytely(R). Sonography diagnosed 10 of 11 patients with acute appendicitis (91%). In three of 10 patients, the findings corresponded to sonographic pitfalls. CONCLUSION: Saline-filled appendiceal ultrasonography enables the detection of a normal appendix and may overcome sonographic pitfalls in acute appendicitis.     

Use of technetium-tagged white blood cells in patients with Crohn's disease and ulcerative colitis: is differential diagnosis possible?

BACKGROUND: Studies have suggested that scans with technetium-tagged white blood cells (WBC-Tc99m) may be equal to endoscopy in the assessment of extent and activity of inflammatory bowel disease (IBD). OBJECTIVE: We have retrospectively examined the accuracy of WBC-Tc99m scans in differentiating continuous from discontinuous colitis in pediatric IBD. MATERIALS AND METHODS: There were 207 children in the study (96 boys, 111 girls, median age 13 years). This included 29 controls - children with no gastrointestinal disease (NL) who underwent WBC-Tc99m scans for other medical problems. Scans were obtained at 30 minutes and 2-4 hours following injection. Scans were interpreted as showing continuous colitis, discontinuous colitis, or no colitis. RESULTS: In the 77 children with active Crohn's disease (CD) of the colon, the scans revealed discontinuous uptake in 63 children and continuous uptake in 14. In the 29 children with ulcerative colitis (UC), 23 scans showed continuous uptake and 6 revealed discontinuous uptake. Two of these 6 showed focal activity near the appendix, and subclinical appendicitis could not be excluded. Another child was bleeding and the scan could have been misinterpreted as showing small- bowel inflammation. In the last three patients, skip areas were clearly identifiable. In none of these last three patients were the biopsies typical of CD (i. e., no granuloma was identified) nor was inflammation patchy. In summary, of the 106 scans showing inflammation, 6 were classified into the wrong group. CONCLUSION: These data show that WBC-Tc99m scanning can be useful in distinguishing discontinuous from continuous colitis.     

Bilateral hypothalamic dopamine infusion in male Zucker rat suppresses feeding due to reduced meal size

PURPOSE: To determine whether vascular, ischemic, and inflammatory causes of bowel wall thickening in children can be differentiated at gray-scale and color Doppler ultrasonography (US). MATERIALS AND METHODS: Thirty-seven children with acute bowel disease underwent graded compression US. Findings of bowel wall thickness, wall echotexture, location of bowel involvement, and presence of color Doppler flow were evaluated. Diagnoses were classified as inflammation (n = 25), vasculitis (n = 7), or ischemia (n = 5) and were confirmed with findings from colonoscopy and biopsy, stool culture analysis, surgery, and cutaneous biopsy, and with a combination of clinical and laboratory data. RESULTS: Patient age (P = .0022), bowel wall thickness (P = .0001), and color Doppler flow (P = .0013) were statistically significantly related to disease type. Wall thickening and absence of visible color Doppler flow suggested ischemia. Older patient age and visible color Doppler flow suggested inflammation, whereas younger patient age and visible color flow suggested vasculitis. Difference in location of bowel disease in patients with ischemic versus those with vascular wall thickening was statistically significant (P = .0185). No difference was found between disease type and wall stratification. CONCLUSION: Gray-scale and color Doppler flow US can aid in differentiating ischemic, vascular, and inflammatory bowel wall thickening.     

Perforated appendicitis in children: risk factors for the development of complications

BACKGROUND: Many aspects of the management of perforated appendicitis in children remain controversial. The objective of this study was to define risk factors associated with the development of postoperative complications in children undergoing treatment for perforated appendicitis. METHODS: We reviewed all children (age < 16 years) who were treated for perforated appendicitis at Cardinal Glennon Children's Hospital between 1988 and 1997. Inclusion criteria included either gross or microscopic evidence of appendiceal perforation. RESULTS: Of 285 children with perforated appendicitis, 279 underwent immediate operative treatment. Mean patient age was 7.7 years and there were no deaths. Major postoperative complications included intra-abdominal abscess (n = 17), ileus (n = 7), mechanical intestinal obstruction (n = 6), and wound infection (n = 4). All children who had a postoperative abscess had more than 5 days of symptoms before operation. Within this subgroup, drain placement was associated with not only decreased postoperative abscess formation and but also shorter duration of fever and length of hospitalization. The incidence of mechanical obstruction or ileus was not increased and the rate of wound infection was actually lower after drainage. CONCLUSIONS: Drain placement appears to be helpful in children with late diagnosis but is of little benefit when the duration of symptoms is less than 5 days. Thus it is likely that drains are most useful in patients with well-established and localized abscess cavities.     

Computed tomography in a case of pseudomembranous colitis

Pseudomembranous colitis (PMC) is an infectious colitis usually occurring as a complication of antibiotic therapy. The computed tomography (CT) findings of 10 patients with PMC are reviewed. All patients demonstrated an abnormal large bowel wall with an average thickness of 13 mm (range 7-31 mm). Additional, but less frequent findings included mesenteric inflammation, ascites, pleural effusions, and dilatation of the large or small bowel. Pancolonic involvement was seen in 7 cases, while three patients had focal colitis. Although the CT appearance of PMC is not specific, the diagnosis may be suggested in the proper clinical setting.     

Developing a patient self-medication program for the rehabilitation setting

Imaging methods provide an important diagnostic basis to clarify mesenteric ischemia. Angiography is the definitive method of investigation in such cases. Other noninvasive methods such as ultrasonography, computed tomography, and magnetic resonance imaging must still prove their importance. We describe three cases of unspecific abdominal pain where the CT shows a mesenteric venous thrombosis with an infarcted bowel. The venous infarcted bowel is clearly demonstrated by CT when other signs for MTV such as ascites, bowel wall thickening, bowel dilatation, and pneumatosis intestinalis are present. CT seems to be a good procedure in order to identify unspecific abdominal pain as being caused by a vascular insufficiency.     

Thoracic actinomycosis: CT findings

PURPOSE: To characterize computed tomographic (CT) findings of thoracic actinomycosis. MATERIALS AND METHODS: Chest CT scans and radiographs obtained in 22 patients with histopathologically proved thoracic actinomycosis were retrospectively reviewed. All patients were immunocompetent; they were aged 12-73 years (mean, 42.6 years; 14 male, eight female). CT findings were correlated with histopathologic findings in nine patients who underwent surgery (lobectomy [n = 8] or segmental resection [n = 1]). RESULTS: All of the lesions were unilateral, with an average diameter of 6.5 cm (range, 2-12 cm). Patchy air-space consolidation (n = 20) or a mass (n = 2) was seen on CT scans. Fifteen (75%) of the 20 patients with air-space consolidation had central areas of low attenuation (5-30 mm in diameter) within the consolidation. Thirteen of the 15 patients underwent contrast medium-enhanced CT. Ten (77%) of the 13 patients showed ring-like rim enhancement. Adjacent pleural thickening was seen in 16 patients (73%). At histopathologic examination, central low-attenuation areas at CT were seen as microabscesses with sulfur granules or a dilated bronchus that contained inflammatory cells and Actinomyces colonies. Peripheral enhancement of the low-attenuation areas was wall of the microabscess or surrounding parenchyma composed of granulation tissue rich in vascularity. CONCLUSION: Findings of chronic segmental air-space consolidation that contained low-attenuation areas with peripheral enhancement or adjacent pleural thickening at CT were suggestive of thoracic actinomycosis.     

Ureteral hydronephrosis secondary to appendicular abscess

OBJECTIVE: To report a case of ureterohydronephrosis secondary to an undiagnosed appendiceal abscess. METHODS/RESULTS: Herein we describe a case of a 4-year-old girl with right ureterohydronephrosis arising from extrinsic compression of the right ureter due to an undiagnosed appendiceal abscess. The patient was treated with intravenous antibiotics and the abscess was drained. Regular isotope and US assessments showed both the residual retroperitoneal fibrosis and renoureteral dilation had decreased. CONCLUSIONS: Acute appendicitis is still the most common cause of emergency abdominal operations in children. Although the symptoms are easily recognizable and generally lead to the correct diagnosis in most cases, the peculiarities of childhood can lead to errors in the diagnosis resulting in the complications reported herein. We emphasize the usefulness of ultrasound in the diagnosis and conservative treatment is advocated.     

Early appendectomy versus an interval appendectomy for appendiceal abscess in children

We retrospectively compared the results of an early appendectomy and an interval appendectomy at a later date after initial conservative treatment in children demonstrating perforated appendicitis with a localized abscess. The preoperative conditions were similar for both groups. The early group (n = 8) showed a statistically significant longer operation time and a greater but not significant blood loss were noted while a larger number of postoperative complications were also observed. On the other hand, in the late operation group (n = 6) initial conservative management including triple antibiotic therapy proved successful without the need to drain the abscess, and thus the interval appendectomy was safely completed without any complications. There were no significant differences between the two groups with respect to length of hospital stay or medical costs. Based on these findings, we thus recommend that initial conservative treatment followed by an interval appendectomy about three months later is a useful strategy for the treatment of appendiceal abscesses in children. However, whether or not an interval appendectomy is appropriate in all patients whose inflammation is suppressed with antibiotics still needs to be clarified.     

Differentiation of achalasia from pseudoachalasia by computed tomography

OBJECTIVES: The purpose of this study was to determine the computed tomography (CT) findings in idiopathic achalasia and in the pseudoachalasia of malignancy. METHODS: We identified 12 patients with the manometric diagnosis of achalasia who also had CT scans available for review: eight had idiopathic achalasia, and four had pseudoachalasia. As controls, we selected nine patients with endoscopically obvious esophageal cancer who also had CT scans. The CT scans were blindly reviewed to determine esophageal wall thickness, symmetry of the esophageal wall, presence of esophageal dilation or mass, and a radiological diagnosis. RESULTS: Six of the eight patients with achalasia had a dilated esophagus. Five had symmetric wall thickening >5 mm (range 7-10 mm) at the gastroesophageal junction. One patient with a 10-mm wall thickening was incorrectly diagnosed with a mass. All others were correctly diagnosed with achalasia. Three of the four patients with pseudoachalasia had esophageal dilation. Two had an obvious esophageal mass. The other two were given an indefinite diagnosis: one had asymmetric wall thickening (11 mm) at the gastroesophageal junction, and the other had symmetric thickening of 18 mm. Eight of the nine patients with obvious esophageal cancer had a mass on CT; the other patient had asymmetric wall thickening of 6 mm at the gastroesophageal junction and was given an indefinite diagnosis. CONCLUSIONS: Most achalasia patients have CT findings of esophageal dilation and mild, symmetric wall thickening. Therefore, symmetric esophageal wall thickening (<10 mm) should not dissuade one from the diagnosis of achalasia. Most pseudoachalasia patients have CT findings of esophageal dilation, more marked and/or asymmetric wall thickening, or mass. In this group, asymmetric or marked thickening (>10 mm) indicated pseudoachalasia. Therefore, CT can be helpful in differentiating between achalasia and the pseudoachalasia of malignancy.     

Imaging of acute right lower abdominal quadrant pain

This article reviews the clinical diagnosis of appendicitis, indications and options for appendiceal imaging, compares appendiceal CT techniques, and describes the imaging findings with appendicitis and alternative conditions that can clinically mimic appendicitis.     

Does warfarin enhance platelet activity?

Salmonella infection can cause appendicitis by direct invasion of the appendix, or can mimic appendicitis by causing mild inflammation of the appendix, ileum, or lymph nodes. Clinical presentation and radiologic and laboratory evaluation may not distinguish the extent of underlying pathology. This case of a child with an atypical presentation of Salmonella who underwent diagnostic laparotomy illustrates the overlap of enteric infections and acute appendicitis. A literature review confirms the variety of clinical scenarios of patients with suspected appendicitis and Salmonella-positive cultures. We conclude that enteric infection should be considered in children with atypical presentations of appendicitis, and that the knowledge that Salmonella can progress to appendicitis should guide management if signs and symptoms of appendicitis develop.     

Using unenhanced helical CT with enteric contrast material for suspected appendicitis in patients treated at a community hospital

OBJECTIVE: We evaluated the accuracy of unenhanced helical CT with enteric contrast material in the diagnosis of appendicitis in children and adults treated at a community hospital. SUBJECTS AND METHODS: Over an 8-month period, 100 consecutive patients with right lower quadrant pain and suspected appendicitis were prospectively evaluated. Thin-collimation helical CT scanning was performed after administration of enteric contrast material. CT interpretations were correlated with surgical pathology (45 patients) and clinical follow-up (55 patients). RESULTS: The findings of 33 CT scans were interpreted as positive for appendicitis (29 true-positives and four false-positives), and the findings of 67 were interpreted as negative for appendicitis (66 true-negatives and one false-negative). Sensitivity was 97%, specificity was 94%, accuracy was 95%, positive predictive value was 88%, and negative predictive value was 99%. In the 67 CT scans with negative findings for appendicitis, an alternative diagnosis was made for 36 patients (54%). CONCLUSION: Unenhanced helical CT with enteric contrast material for the evaluation of appendicitis can be implemented in a community hospital. In our study, such imaging achieved excellent accuracy.     

Internal carotid artery narrowing in children with retropharyngeal lymphadenitis and abscess

BACKGROUND AND PURPOSE: Our purpose was to describe the association between narrowing of the internal carotid artery (ICA) and retropharyngeal abscess in children. METHODS: Neck CT scans from 13 consecutive children with suppurative retropharyngeal lymphadenitis and abscess were evaluated retrospectively for asymmetric ICA diameters at the level of the abscess. Clinical status at the time of illness was established via a chart review. Twenty control CT scans obtained from pediatric patients with normal imaging findings were evaluated prospectively to determine symmetry and size of the ICA. RESULTS: Mean diameter of the normal ICA, contralateral to the retropharyngeal abscess, was 5 mm (range, 3-8 mm), while mean diameter ipsilateral to the abscess was 3 mm (range, 1-5 mm). The diameters of the normal and abnormal ICAs were statistically significantly different. All children were neurologically normal. The right and left ICAs in children with normal CT findings in the neck were symmetrical in diameter. CONCLUSION: Despite dramatic narrowing of the ICA ipsilateral to retropharyngeal lymphadenitis and abscess, no children in this series had neurologic deficits, suggesting that such narrowing is a common, benign, and, most likely, incidental imaging finding.     

Usefulness of CT in patients with intestinal obstruction who have undergone abdominal surgery for malignancy

OBJECTIVE: The purpose of this study was to evaluate the usefulness of CT in determining the causes of intestinal obstruction in patients who have undergone abdominal surgery for malignancy. MATERIALS AND METHODS: We analyzed the CT scans of 55 patients with benign (n = 26) or malignant (n = 29) intestinal obstruction that developed after abdominal surgery for malignancy. After calculating the diagnostic accuracy of interpretations by three radiologists, we compared CT findings for benign and malignant intestinal obstructions with respect to peritoneal involvement patterns and other ancillary findings. Multivariate logistic regression analysis was used to determine the diagnostic performance of CT in revealing causes of obstruction. RESULTS: Diagnostic accuracies of the three radiologists were 67%, 75%, and 78%. CT findings indicating malignant obstruction were a mass at the site of obstruction or prior surgery, lymphadenopathy, or an abrupt transition zone and irregular bowel wall thickening at obstructed sites (p < .05). Conversely, the chance for benign obstruction increased when CT revealed mesenteric vascular changes, a large amount of ascites, or a smooth transition zone and smooth bowel wall thickening at the obstructed site (p < .05). With multivariate logistic regression analysis using two variables (a mass at the site of obstruction or prior surgery and lymphadenopathy), we calculated the overall accuracy of CT as 84% (46/55 patients). CONCLUSION: CT is useful in differentiating benign from malignant intestinal obstructions in patients who have undergone abdominal surgery for malignancy. However, CT has limitations in patients not having a demonstrable peritoneal mass.