Diagnostic value of maximal-outer-diameter and maximal-mural-thickness in use of ultrasound for acute appendicitis in children

Contrast-enhanced ultrasonography findings of LAMNs with peritoneal and splenic metastases: a case report and literature review

Low-grade appendiceal mucinous neoplasms (LAMNs) are rare appendiceal tumors that are primarily diagnosed using computed tomography(CT) enhancement and magnetic resonance imaging (MRI). Herein, we report the sonographic features, especially for contrast-enhanced ultrasound (CEUS), of a 70-year-old female with an unusual LAMN metastasizing to the peritoneum and spleen. The patient had a right pelvic mass 2 days prior to presentation. Two-dimensional (2D) ultrasound revealed a mixed cystic-solid mass in the right lower abdomen and spleen parenchyma; CEUS showed heterogeneous enhancement in both areas, suspected to be a mucinous mass. CT enhancement and MRI findings revealed concurrent findings. Histopathologically, LAMN lesions were confirmed in the appendix, spleen, and peritoneum of the specimens obtained during exploratory laparoscopy. No recurrences were reported at three years postoperatively. LAMN lesions may metastasize to abdominal organs, and imaging examinations are essential for diagnosis. This study presents major ultrasonography and CEUS findings for the diagnosis of LAMNs.

Ultrasonographic evaluation of cecal appendix diameter in pediatric population

Objective

To stratify ultrasound samples in a pediatric population undergoing evaluation for acute appendicitis to examine the variability in cecal appendix diameter, in different age groups, and to determine whether there is a prevalent value for each age group.

Methods

A retrospective cross-sectional study with 196 children aged 0 to 15 years. Data were extracted from reports of ultrasound examinations carried out between 2008 and 2015. Children with sonographic diagnosis of appendicitis or other signs of periappendiceal inflammation were excluded.

Results

The evaluation of the anteroposterior measurement of the cecal appendix revealed a mean diameter of 4.14mm (standard deviation: 0.93mm; 95%CI: 3.86-4.14). Cecal appendix diameter did not differ significant between age groups.

Conclusion

Evaluation of the anteroposterior diameter of the cecal appendix in centimeters in a sample of 196 children aged 0 to15 years revealed a mean diameter of 4.14mm (standard deviation, 0.93mm. There were no significant differences in cecal appendix diameter following stratification by age. Results indicate a single value can be adopted for mean cecal appendix diameter in pediatric populations.

Predictors for Acute Appendicitis in Children

BACKGROUND

Acute appendicitis in children is the most common condition requiring urgent evaluation and surgery in the emergency department. At times, despite the appendix being seen on ultrasound (US), there can be discrepancy as to whether a patient has clinical appendicitis. Secondary findings suggestive of appendicitis can be helpful in identifying and evaluating these children.

OBJECTIVE

The aim of this study was to determine if specific US findings and/or laboratory results are predictive of appendicitis in children with a visualized appendix on US.

METHODS

A prospective study was conducted on children (birth to 18 years) presenting to the pediatric emergency department with suspected appendicitis who underwent right-lower-quadrant US. Ultrasound findings analyzed appendix diameter, compressibility, increased vascularity, presence of appendicolith, inflammatory changes, right-lower-quadrant fluid near the appendix, lower abdominal fluid, tenderness during US, and lymph nodes. Diagnosis was confirmed via surgical pathology.

RESULTS

There were 1252 patients who enrolled, 60.8 (762) had their appendix visualized, and 39.1 (490) did not. In children where the appendix was seen, 35.2% (268) were diagnosed with appendicitis. Among patients with a visualized appendix, the likelihood of appendicitis was significantly greater if the appendix diameter was 7 mm or greater (odds ratio [OR], 12.4; 95% confidence interval [CI], 4.7-32.7), an appendicolith was present (OR, 3.9; 95% CI, 1.5-10.3), inflammatory changes were seen (OR, 10.2; 95% CI, 3.9-26.1), or the white blood cell (WBC) count was 10,000/μL (OR, 4.8; 95% CI, 2.4-9.7). A duration of abdominal pain of 3 days or more was significantly less likely to be associated with appendicitis (OR, 0.3; 95% CI, 0.08-0.99). The absence of inflammatory changes, WBC count of less than 10,000/μL, and appendix diameter of 7 mm or less had a negative predictive value of 100%.

CONCLUSIONS

When the appendix is seen on US but diagnosis of appendicitis is questioned, the absence of inflammatory changes, WBC count of less than 10,000/μL, and appendix diameter of 7 mm or less should decrease suspicion for appendicitis.

Acute Appendicitis or Lymphoid Hyperplasia: How to Distinguish More Safely?

PURPOSE

Lymphoid hyperplasia can be an important mimicker of acute appendicitis by creating a non-compressible appendix more than 6 mm in diameter. The aim of this study was to evaluate methods of distinguishing lymphoid hyperplasia and appendicitis on the basis of sonography, lamina propria thickness, and Alvarado scoring.

METHODS

This retrospective study included 259 patients (142 appendicitis, 117 lymphoid hyperplasia). The US (ultrasound) reports of the patients were reviewed and the maximum diameter of the appendix, the presence or absence of increased echogenicity of the surrounding pericaecal fat, local fluid collection, the presence of reactive lymph nodes in the periappendiceal area, and mural hyperemia within the appendix were recorded.

RESULTS

The use of additional sonographic criteria, lamina propria thickness (≤1 mm is indicative for appendicitis), or Alvarado scoring (>6 mm is indicative for appendicitis) provided a true-positive diagnosis for acute appendicitis.

CONCLUSION

The presence of local fluid collection in the periappendiceal area and a lamina propria thickness ≤ 1 mm are the most successful parameters for distinguishing appendicitis from lymphoid hyperplasia.

Size matters: Computed tomographic measurements of the appendix in emergency department scans

BACKGROUND

Radiologists use a size cutoff in appendiceal diameter to assist surgeons in diagnosing appendicitis, however, no consensus exists as to the size of a normal adult appendix. We aim to evaluate radial appendiceal diameter on CT in adult patients both with and without appendicitis.

METHODS

Retrospective review of adults who underwent abdominal CT was performed. Variables collected include: demographics, BMI, WBC count at presentation, radial diameter of appendix (mm), presence of fat stranding, fecalith, and free fluid.

RESULTS

During the study period, 3099 patients underwent CT. The appendix was visualized on 74% of scans. Mean appendiceal diameter was 6.6 mm (±1.7). The appendix was larger in patients with appendicitis (6.6 vs. 11.4; p < 0.0001). Overall appendectomy incidence was 3.2%. Sensitivity and specificity of CT in diagnosing appendicitis in this cohort of patients were 90% and 94%. NPV was 99.5%.

CONCLUSION

While appendiceal diameter was larger in patients with appendicitis, >20% of patients without appendicitis had an appendiceal diameter >7 mm. Diameter alone should not be relied upon to diagnose appendicitis.

Revisiting the Appendiceal Diameter via Ultrasound for the Diagnosis of Acute Appendicitis

OBJECTIVES

This study aims to investigate the optimal outer appendiceal diameter via ultrasound for the diagnosis of acute appendicitis.

METHODS

A retrospective chart review was conducted on patients (ages, 2-18 years) presenting to an urban pediatric emergency department between January 1, 2009 and December 31, 2010 with suspected acute appendicitis. Children were considered as having "suspected acute appendicitis" if they (1) presented with acute abdominal pain and had either a surgical consult or an abdominal ultrasound, or (2) presented or transferred with the stated suspicion of acute appendicitis. Pathology reports were used to confirm the diagnosis of appendicitis. The appendiceal diameters were determined by board-certified pediatric radiologists.

RESULTS

A total of 320 patient charts were reviewed (females, 57%; mean age, 10.9; SD, 3.9). Seventy-two percent (N = 230) of the patients screened positive for acute appendicitis via ultrasound, 69% (N = 222) had confirmed acute appendicitis, 75% (N = 239) of the ultrasound reports included an outer appendiceal diameter. Overall, ultrasound was found to be highly sensitive (91%) and moderately specific (74%). With an outer appendiceal diameter of 6 mm as a cutoff, ultrasound had an excellent sensitivity (100%) but poor specificity (43%). With an outer diameter of 7 mm as a cutoff, sensitivity decreased to 94% but specificity increased to 71%. With increasing cutoff size, the sensitivity decreased and specificity increased.

CONCLUSIONS

Our data suggest that the optimal outer appendiceal diameter for the diagnosis of acute appendicitis should be 7 mm instead of the currently used 6 mm.

Does size matter? Correlation of ultrasound findings in children without clinical evidence of acute appendicitis

PURPOSE

The purpose of this study was to determine whether children with a positive ultrasound (US) for acute appendicitis but a negative clinical picture developed appendicitis requiring definitive management.

METHODS

After obtaining IRB approval, we conducted a retrospective review of patients ≤17years who presented with possible acute appendicitis between April 1st, 2014, and December 31st, 2015. We included patients with a US suggestive of acute appendicitis based on size criteria but without concerning clinical features. Patients were discharged from the emergency department (ED) or admitted for observation. Variables included demographic data, US characteristics, clinical findings, length of follow-up, and appendectomy.

RESULTS

Of the 31 patients identified, 45% were male and average age was 11.3yrs. On US, the average maximal diameter of the appendix was 6.93mm. The median length of follow-up was 16.8 months, including 10 returns to the ED by 9 patients. Three of these underwent immediate laparoscopic appendectomy, while one had interval appendectomy. There were no cases of perforated appendicitis, and only 2 cases demonstrated pathology consistent with appendicitis.

CONCLUSION

These findings demonstrate that it is safe to consider conservative measures such as observation or discharge in children with a positive US for appendicitis based on size criteria but a negative clinical picture.

LEVEL OF EVIDENCE

4.

Does elevated urinary 5-hydroxyindole acetic acid level predict acute appendicitis in children?

BACKGROUND

Acute appendicitis is the most common abdominal surgical emergency in children, and appendectomy is the most frequent acute abdominal operation. Prompt diagnosis and surgical treatment are required to reduce the risk of perforation and prevent complications, especially in small children. Enterochromaffin cells that contain large amounts of serotonin are mostly located in the distal appendix. Serotonin metabolite 5-hydroxyindoleacetic acid (5-HIAA) could therefore be a marker for acute appendicitis.

OBJECTIVE

We tested urinary 5-HIAA concentrations in spot urine samples from children with acute appendicitis.

METHODS

We enrolled 93 patients who underwent surgery for suspicion of acute appendicitis. The diagnosis was made intraoperatively and confirmed histopathologically. Additionally, urine samples from 102 healthy children were collected as controls. Their 5-HIAA was measured using high-performance liquid chromatography.

RESULTS

Acute appendicitis was diagnosed in 81 patients, whereas there were other explanations for abdominal pain in the remaining 12 patients in the non-appendicitis group. The control group comprised 102 healthy children. Considering the median of all measured 5-HIAA values as the cut-off, we analysed the proportions of patients with elevated values in all the groups. Our analysis showed that statistically there was no significant difference in the distribution of percentages among the groups. The area under the curve for 5-HIAA was 0.55 (95% CI 0.47 to 0.62) with sensitivity and specificity 60.4% and 48.9%, respectively.

CONCLUSIONS

Urine 5-HIAA concentration measured in spot samples is not a reliable method for diagnosing acute appendicitis in children.

Application of scoring systems with point-of-care ultrasonography for bedside diagnosis of appendicitis

BACKGROUND

Appendicitis is a common disease requiring surgery. Bedside ultrasound (BUS) is a core technique for emergency medicine (EM). The Alvarado score is a well-studied diagnostic tool for appendicitis. This study aimed to investigate the relationship between patients' symptoms, Alvarado score and ultrasound (US) findings, as performed by emergency physicians (EPs) and radiologists, of patients with suspected appendicitis.

METHODS

Three EM specialists underwent the BUS course and core course for appendicitis assessment. Patients suspected of having appendicitis were selected and their Alvarado and modified (m) Alvarado scores calculated. The specialists performed the BUS. Then, patients were given a formal US and surgery consultation if necessary. Preliminary diagnoses, admission or discharge from the emergency department (ED) and final diagnosis were documented. The patients were also followed up after discharge from the hospital.

RESULTS

The determined cut-off value was 2 for Alvarado and 3 for mAlvarado scores. The sensitivities of the two scores were 100%. Each score was used to rule out appendicitis. The results of EP-performed BUS were as follows: accuracy 70%, sensitivity 0.733, specificity 0.673, + LR 2.24, and - LR 0.40 (95%CI). Radiologists were better than EPs at diagnosing appendicitis and radiologists and EPs were equally strong at ruling out appendicitis by US. When US was combined with Alvarado and mAlvarado scores, EP US+Alvarado/mAlvarado scores <3 and radiology US+Alvarado/mAlvarado scores <4 perfectly ruled out appendicitis.

CONCLUSION

BUS performed by EPs is moderately useful in detecting appendicitis. Combined with scoring systems, BUS may be a perfect tool for ruling out decisions in EDs.

Appendiceal diameter: CT versus sonographic measurements

BACKGROUND

Ultrasound and CT are the dominant imaging modalities for assessment of suspected pediatric appendicitis, and the most commonly applied diagnostic criterion for both modalities is appendiceal diameter. The classically described cut-off diameter for the diagnosis of appendicitis is 6 mm when using either imaging modality.

OBJECTIVE

To demonstrate the fallacy of using the same cut-off diameter for both CT and US in the diagnosis of appendicitis.

MATERIALS AND METHODS

We conducted a retrospective review of patients younger than 18 years who underwent both US and CT of the appendix within 24 h. The shortest transverse dimension of the appendix was measured at the level of the proximal, mid and distal appendix on US and CT images. We compared mean absolute difference in appendiceal diameter between US and CT, using the paired t-test.

RESULTS

We reviewed exams of 155 children (58.7% female) with a mean age of 11.3 ± 4.2 years; 38 of the children (24.5%) were diagnosed with appendicitis. The average time interval between US and CT was 7.0 ± 5.4 h. Mean appendiceal diameter measured by CT was significantly larger than that measured by US in cases without appendicitis (5.3 ± 1.0 mm vs. 4.7 ± 1.1 mm, P < 0.0001) and in cases with appendicitis (8.3 ± 2.2 mm vs. 7.0 ± 2.0 mm, P < 0.0001). Mean absolute diameter difference at any location along the appendix was 1.3-1.4 mm in normal appendices and 2 mm in cases of appendicitis.

CONCLUSION

Measured appendiceal diameter differs between US and CT by 1-2 mm, calling into question use of the same diameter cut-off (6 mm) for both modalities for the diagnosis of appendicitis.

Improvement in diagnostic accuracy of ultrasound of the pediatric appendix through the use of equivocal interpretive categories

OBJECTIVE

The purpose of this article is to evaluate the diagnostic performance of ultrasound of the pediatric appendix using standardized structured reports that incorporate equivocal interpretive categories.

MATERIALS AND METHODS

Standardized structured appendix ultrasound reports using a five-category interpretive scheme were reviewed. Interpretive categories were positive, intermediate likelihood, or negative when the appendix was visualized, and secondary signs or no secondary signs when the appendix was not visualized. Interpretations were compared with clinical and pathologic follow-up. Diagnostic accuracy was compared with the accuracy of a simulated binary interpretive scheme based on the same data.

RESULTS

One thousand three hundred fifty-seven examinations were included, with appendicitis present in 16.9% (230/1357) of cases. The appendix was visualized in 47.2% (641/1357) of cases, with interpretations as follows: positive, 27.5% (176/641); intermediate likelihood, 9.7% (62/641); and normal, 62.9% (403/641). The appendicitis rate in each group was 92.6% (163/176), 25.8% (16/62), and 0.5% (2/403), respectively. The appendix was not visualized in 52.8% (716/1357) of cases, with secondary findings identified in 8.5% (61/716) and no secondary findings in 91.5% (655/716) of cases. The appendicitis rate was 39.3% (24/61) and 3.8% (25/655) in these groups, respectively. Appendicitis was present in 32.5% of equivocal (intermediate likelihood and not visualized, secondary findings) cases and 2.6% of negative (normal and not visualized, no secondary findings) cases. Diagnostic accuracy of a five-category scheme was 96.8% versus 94.1% for a binary scheme.

CONCLUSION

Appendix ultrasound examinations interpreted according to a scheme that incorporates equivocal categories better convey diagnostic certainty and increase diagnostic accuracy compared with a binary interpretive scheme.

Appendiceal diameter as a predictor of appendicitis in children: improved diagnosis with three diagnostic categories derived from a logistic predictive model

OBJECTIVES

To develop and assess the performance of a diameter-based logistic predictive model and a derived 3-category interpretive scheme for the sonographic diagnosis of paediatric appendicitis.

METHODS

Appendiceal diameters were extracted from reports of ultrasound examinations in children and young adults. Data were used to generate a logistic predictive model which was used to define negative, equivocal and positive interpretive categories. Diagnostic performance of the derived 3-category interpretive scheme was compared with simulated binary interpretive schemes.

RESULTS

Six hundred forty-one appendix ultrasound reports were reviewed with appendicitis present in 181 (28.2 %). Cut-off diameters based on the logistic predictive model were ≤6 mm = normal, >6 mm-8 mm = equivocal and >8 mm = positive with appendicitis present in 2.6 % (11/428), 64.9 % (72/111) and 96.1 % (98/102) of cases in each group. These cut-offs conferred 97.2 % accuracy with 17.3 % (111/641) of cases considered equivocal. Of the binary cut-offs, a 6 mm cut-off performed best with 91.6 % accuracy. AIC analysis favoured the logistic model over the binary model for prediction of appendicitis.

CONCLUSIONS

A 3-category interpretive scheme based on a logistic predictive model provides higher accuracy in the diagnosis of appendicitis than traditional binary diameter cut-offs. Inclusion of an equivocal interpretive category more accurately reflects the probability distribution of prediction of appendicitis by ultrasound.

KEY POINTS

• Three diameter categories outperform a 6-mm cut-off to diagnose appendicitis • Three categories allow more confident exclusion of appendicitis • Three categories allow more confident diagnosis of appendicitis • Three categories more accurately reflect the probability of appendicitis by ultrasound.

Does appendiceal diameter change with age? A sonographic study

OBJECTIVE

The purposes of this study were to determine whether age-related changes in appendiceal diameter identified on CT and pathology are apparent on sonography and to assess the relationship between normal appendiceal diameter and patient-specific factors.

MATERIALS AND METHODS

Ultrasound examinations from 388 unique pediatric patients with normal appendixes, evenly distributed by age, were reviewed. Appendiceal diameter and wall thickness were correlated with patient age, sex, height, weight, and presence of enlarged lymph nodes.

RESULTS

Mean (± SD) anteroposterior and transverse appendiceal diameters were 4.4 ± 0.9 and 5.1 ± 1.0 mm, respectively. Appendiceal diameter was normally distributed across the population but was not significantly associated with age. Centers for Disease Control and Prevention (CDC) weight percentile for age was the only statistically significant patient-specific predictor of transverse diameter (p = 0.001) and approached significance for anteroposterior diameter (p = 0.051). The presence of enlarged lymph nodes was a significant predictor of anteroposterior diameter (p = 0.029) and approached significance for transverse diameter (p = 0.07). Wall thickness was normally distributed across the population and was significantly associated with age (p = 0.011; effect size, -0.05 mm/y).

CONCLUSION

Appendiceal diameter measured on ultrasound is normally distributed in children and does not depend on age. Age-dependent diagnostic cutoffs for normal sonographic diameter are thus not needed. There is, however, a relationship between age and appendiceal wall thickness, suggesting the need for age-dependent diagnostic values if this criteria are to be used to diagnose appendicitis. Although the CDC weight percentile for age and the presence of enlarged lymph nodes affect appendiceal diameter on ultrasound, these effects are small and of doubtful clinical significance.

Acute appendicitis in children: ultrasound and CT findings in negative appendectomy cases

BACKGROUND

To decrease the negative appendectomy rate in children, knowledge of the misleading imaging findings on US and CT in negative appendicitis cases is important.

OBJECTIVE

To evaluate the negative appendectomy rate and describe the imaging findings of US and CT that lead radiologists to misdiagnose acute appendicitis in children.

MATERIALS AND METHODS

From 2007 to 2013, 374 children operated for suspected appendicitis were proved to either have acute appendicitis (n = 348) or to be negative for appendicitis (n = 26) on pathological reports. Negative appendectomy rates were compared among imaging modalities, age groups and genders. We retrospectively reviewed US and CT findings from negative appendectomy cases.

RESULTS

The overall negative appendectomy rate was 7.0% (26/374). There were no statistically significant differences among the subgroups. The most common misleading presentations on US were sonographic tenderness (9/16, 56%) and non-compressibility (9/16, 56%). The most common misleading finding on CT were the presence of an appendicolith or hyperdense feces (5/12, 42%). Periappendiceal fat inflammation was observed in only one case of negative appendicitis on US and on CT.

CONCLUSION

Radiologists can misdiagnose children with equivocal diameters of appendices as having acute appendicitis when sonographic tenderness or non-compressibility is present on US and when an appendicolith or hyperdense feces is noted on CT. The possibility of negative appendicitis should be borne in mind when periappendiceal fat inflammation is absent or minimal in indeterminate cases.

Bedside ultrasonography as an adjunct to routine evaluation of acute appendicitis in the emergency department

Introduction

Appendicitis is a common condition presenting to the emergency department (ED). Increasingly emergency physicians (EP) are using bedside ultrasound (BUS) as an adjunct diagnostic tool. Our objective is to investigate the test characteristics of BUS for the diagnosis of appendicitis and identify components of routine ED workup and BUS associated with the presence of appendicitis.

Methods

Patients four years of age and older presenting to the ED with suspected appendicitis were eligible for enrollment. After informed consent was obtained, BUS was performed on the subjects by trained EPs who had undergone a minimum of one-hour didactic training on the use of BUS to diagnose appendicitis. They then recorded elements of clinical history, physical examination, white blood cell count (WBC) with polymophonuclear percentage (PMN), and BUS findings on a data form. We ascertained subject outcomes by a combination of medical record review and telephone follow-up.

Results

A total of 125 subjects consented for the study, and 116 had adequate image data for final analysis. Prevalence of appendicitis was 40%. Mean age of the subjects was 20.2 years, and 51% were male. BUS was 100% sensitive (95% CI 87–100%) and 32% specific (95% CI 14–57%) for detection of appendicitis, with a positive predictive value of 72% (95% CI 56–84%), and a negative predictive value of 100% (95% CI 52–100%). Assuming all non-diagnostic studies were negative would yield a sensitivity of 72% and specificity of 81%. Subjects with appendicitis had a significantly higher occurrence of anorexia, nausea, vomiting, and a higher WBC and PMN count when compared to those without appendicitis. Their BUS studies were significantly more likely to result in visualization of the appendix, appendix diameter >6mm, appendix wall thickness >2mm, periappendiceal fluid, visualization of the appendix tip, and sonographic Mcburney’s sign (p<0.05). In subjects with diagnostic BUS studies, WBC, PMN, visualization of appendix, appendix diameter >6mm, appendix wall thickness >2mm, periappendiceal fluid were found to be predictors of appendicitis on logistic regression.

Conclusion

BUS is moderately useful for appendicitis diagnosis. We also identified several components in routine ED workup and BUS that are associated with appendicitis generating hypothesis for future studies.

When does ultrasonography influence management in suspected appendicitis?

BACKGROUND

Accurate diagnosis of appendicitis is challenging, particularly in children. Moreover, opinion is divided over the role of ultrasonography (US) in its diagnosis and how US may influence management. This study compares the use of US in two tertiary paediatric hospitals and how it influenced the management of suspected appendicitis.

METHODS

Data from acute admissions, radiology, histopathology and theatre were cross-referenced to review all children who underwent an appendicectomy (with or without preoperative US) for suspected appendicitis in Christchurch (CH) in New Zealand and Aberdeen (AB) in Scotland in 2009.

RESULTS

Five hundred and ninety-nine patients (442 CH; 157 AB) were included, with similar age and gender distributions. US was performed in 23% of patients with an overall appendix visualization rate of 29%. The overall positive and negative predictive values were 67% and 100%, respectively. Females were more likely to have US than males (P < 0.001, χ(2) ). In females with no appendix seen on US, in the presence or absence of other pathology, a normal appendix was confirmed in 50% and 58%, respectively. Visualizing the appendix resulted in a lower rate of normal appendix at operation (20%, 4/20) compared with when the appendix was not visualized (56%, 14/25).

CONCLUSION

Identification of a normal appendix on US seems sufficiently accurate to exclude appendicitis with confidence, while positive US should be interpreted in conjunction with the clinical features in influencing the decision to operate. The incidence of a non-inflamed appendix at operation could be reduced with an increased rate of appendiceal visualization by sonographers.

Acute appendicitis: investigating an optimal outer appendiceal diameter cut-point in a pediatric population

BACKGROUND

Acute appendicitis is the most common cause of abdominal pain in children requiring operative intervention. Among a number of sonographic criteria to aid in the diagnosis of appendicitis, an outer diameter >6 mm is the most objective and widely accepted. However, there is a lack of evidence-based standards governing this consensus.

STUDY OBJECTIVES

The aim of this study was to determine the outer appendiceal diameter that maximizes sensitivity and specificity in a pediatric population.

METHODS

A retrospective review of all urgent diagnostic ultrasounds (US) was performed over 2 years in children aged <18 years. The diagnostic accuracy of various cut-points was assessed by calculating the sensitivity and specificity and plotting a receiver operating characteristic (ROC) curve.

RESULTS

The study sample consisted of 398 patients in whom the appendix was visualized on US. The median outer appendiceal diameter was significantly higher in the surgical group compared to the nonsurgical group (9.4 mm; range = 8.1-12.0 vs. 5.5 mm; range = 4.4-6.5, p < 0.01). The optimal cut-point with the greatest area under the ROC curve was determined to be an outer appendiceal diameter of 7.0 mm.

CONCLUSIONS

In our patients, adopting a 7-mm rather than a 6-mm appendiceal diameter threshold would balance a greater number of missed cases of acute appendicitis for a reduction in the number of unnecessary surgeries.

Reevaluating the sonographic criteria for acute appendicitis in children: a review of the literature and a retrospective analysis of 246 cases

RATIONALE AND OBJECTIVES

There has been little rigorous evaluation of the sonographic criteria for acute appendicitis in children. Our clinical experience has called the traditional diagnostic criteria into question. We set out to review the literature, evaluate the most commonly applied diagnostic criteria for acute appendicitis, and identify those criteria that best predict the presence of disease.

MATERIALS AND METHODS

A critical review of the literature concerning the sonographic diagnosis of acute appendicitis was performed. Based on diagnostic criteria identified in that review, two independent, blinded pediatric radiologists retrospectively reviewed 246 right lower quadrant ultrasound examinations in which the appendix was identified with attention to commonly described diagnostic criteria for acute appendicitis. Multivariate and classification and regression tree analysis were performed to identify criteria that predict appendicitis.

RESULTS

In a multivariate analysis, inflammation of the periappendiceal fat is the only finding that statistically significantly predicts acute appendicitis (OR = 68.93, P < .0001). Other criteria such as diameter, noncompressibility, hyperemia, the presence of an appendicolith, and loss of stratification of the appendiceal wall do not independently predict appendicitis.

CONCLUSION

Periappendiceal fat infiltration is the most important diagnostic criterion for acute appendicitis in children. Strict application of other criteria such as diameter should be avoided.

A critical evaluation of US for the diagnosis of pediatric acute appendicitis in a real-life setting: how can we improve the diagnostic value of sonography?

BACKGROUND

We have observed that day-to-day use of US for acute appendicitis does not perform as well as described in the literature.

OBJECTIVE

Review the diagnostic performance of US in acute appendicitis with attention to factors that influence performance.

MATERIALS AND METHODS

Retrospective review of all sonograms for acute appendicitis in children from May 2005 to May 2010 with attention to the rate of identification of the appendix, training of personnel involved and diagnostic accuracy.

RESULTS

The appendix was identified in 246/1,009 cases (24.4%), with identification increasing over time. The accuracy of US was 85-91% with 35 false-positives and 54 false-negatives. Pediatric sonographers were significantly better at identifying the appendix than non-pediatric sonographers (P < 0.0001). Increased weight was the only patient factor that influenced identification of the appendix (P = 0.006). CT use was stable over the 5 years but declined in cases where the appendix was identified by US.

CONCLUSION

In day-to-day use, US does not perform as purported in the literature. We do not visualize the appendix as often as we should and false-negative and false-positive exams are too common. To improve the diagnostic performance of this modality, involvement by experienced personnel and/or additional training is needed.

Improving the diagnostic accuracy of ultrasonography in suspected acute appendicitis by the combined transabdominal and transvaginal approach

Transabdominal ultrasound has a lower diagnostic yield in acute appendicitis than computed tomography (CT) scanning. The addition of transvaginal sonography in women with suspected appendicitis has shown improvement in the efficacy of diagnosis, potentially providing the option of selective CT use and reducing overall investigative cost and surgical delay. Two hundred ninety-two women who underwent combined transabdominal and transvaginal ultrasound for suspected acute appendicitis were evaluated. Patients were divided into two groups; Group 1 including patients with a positive sonographic diagnosis of appendicitis who underwent operation and Group 2 including patients with a negative sonographic diagnosis. Of the 157 women in Group 1, the diagnosis of appendicitis was histologically confirmed in 144 patients with five cases having a normal appendix in whom eight other pathologies were found. Of the 135 women with negative ultrasound examinations, 14 underwent surgery in which four cases of appendicitis were found. The sensitivity of the combined approach was 97.3 per cent, the specificity 91 per cent, the positive predictive value 91.7 per cent, and the negative predictive value 97 per cent. Combined ultrasound has a high predictive value for the diagnosis of appendicitis and may assist in reduction of the use of CT scanning for diagnosis and in the negative appendectomy rate.

The diagnostic value of indirect ultrasound signs during acute adult appendicitis

PURPOSE

To evaluate the diagnostic value of indirect ultrasound signs during acute appendicitis.

PATIENTS AND METHODS

Our retrospective study lasted 5 years, from May 2005 to April 2010. It concerned 620 cases of appendectomy performed following prior ultrasound examination of the right iliac fossa (RIF). In 448 cases, ultrasonography clearly showed the appendix, which was inflamed. The presence of indirect signs of appendix inflammation without visualisation of the appendix was confirmed by ultrasound examination in 160 cases. In 12 cases, the appendix was not visualised nor were there any indirect signs on the ultrasound image. The indirect signs involved were hypertrophy of the peritoneal fat (HPF), pain caused by compression on exploration of the right iliac fossa, and localised hypokinesia in the digestive loops (LHL). We compared the results found by ultrasonography with the operative and anatomical pathology reports.

RESULTS

The positive predictive value of the indirect signs of appendicitis on the ultrasound scan was 95.8% if the three indirect signs were associated, 87.5% for the association of pain and HPF, 45.8% for the association of pain and LHL, and 25% if there was just pain. The negative predictive value of the indirect signs of appendicitis on the ultrasound scan was 57.2% if the three signs were associated, 65.9% for the association of pain and HPF and 60.7% for the association of pain and LHL, with 83.3% for pain alone. The sensitivity of the indirect signs was 83.9% if the three signs were associated, 31.8% for the association of pain and HPF, 50% for the association of pain and LHL, and 50% if there was just pain. The specificity of the indirect signs was 85.7% if the three signs were associated, 96.7% for the association of pain and HPF, 56.7% for the association of pain and LHL, and 62.5% if there was just pain.

CONCLUSION

When tomodensitometry cannot be performed and the appendix is not visible on ultrasound examination, indirect ultrasound signs must be systematically sought, particularly in populations in which appendicitis are highly prevalent.

Appendicitis in the Deep Pelvis

Sonography is an excellent tool to identify the appendix in patients with abdominal pain. If a normal appendix is identified, then a search for alternative pathology can be pursued. Identifying the appendix can be challenging: the location varies, overlying bowel gas interferes, and patient size can affect the resolution. Specific sonographic findings can help identify when an appendix is inflamed. A positive appendicitis may present with varying sonographic characteristics, and the tip of the appendix may present in atypical locations. The classic location of the appendix originates off the cecum with the tip draping over the iliac vessels in the right lower quadrant. This case report describes a case of appendicitis in the deep pelvis. Sonography of the appendix bears enormous responsibility and, when done correctly, may still require clinical corroboration.

Ultrasonography of normal and abnormal appendix in children

Appendicitis is the most common acute surgical emergency of childhood. Since the original report by Puylaert in 1986, the use of ultrasonography in the diagnosis of appendicitis has been the subject of considerable study. Among the reported diagnostic criteria, the maximal outer diameter (MOD) of the appendix is accepted as the one of the most reliable criteria used to differentiate between a normal appendix and acute appendicitis. However, MOD measurement is subject to inaccuracies because luminal distention by non-compressible, non-inflammatory material such as fecal material, or increased maximal mural thickness due to reactive mucosal lymphoid hyperplasia, or a medical cause due to a generalized gastrointestinal disease, such as Crohn’s disease, can cause the measurement to exceed the upper limits of normality. The aim of this article is to introduce the spectrum of ultrasonographic findings in the normal and abnormal appendix and eventually to reduce unnecessary surgery in children.

Diagnostic value and clinical utility of contrast enhanced ultrasound in intestinal diseases

Contrast enhanced ultrasound (CEUS) has recently gained increasing attention as it clearly improves the visualisation of perfusion in various tissues. The development of second generation contrast enhancing agents used in low-mechanical-index harmonic ultrasound has enabled real-time assessment of the microvascular circulation and quantification of bowel wall vascularity. For this review Medline was searched for clinical studies using CEUS to investigate the gastrointestinal tract. Many studies demonstrate that acute or chronic inflammation of the intestinal wall is accompanied by increased perfusion of the mesentery, which can be displayed semi-quantitatively using contrast enhanced ultrasound analyzing time intensity curves. In contrast, ischemia is characterized by hypoperfusion of the mesenteric arteries and the bowel wall. The most promising sonographic approach in assessing splanchnic arteries and the bowel wall is combining the analysis of superior and inferior mesenteric inflow by pulsed Doppler scanning (systolic and diastolic velocities, resistance index) with the end-organ vascularity by CEUS. CEUS at a preliminary stage has been described as clinically important in a variety of gastrointestinal disorders, particularly in patients with Crohn's disease. CEUS facilitates the detection of disease extent and activity, and its luminal and extraluminal complications.

Diagnostic value of ultrasonography for detection of intestinal diseases

When ultrasonography was initially introduced into clinical practice, its use for detection of intestinal diseases was greatly restricted due to the problem that ultrasound imaging is greatly affected by gas. However, with the development of ultrasound technology, ultrasonography has been applied widely to the detection of intestinal diseases in recent years. In this article, we will review the application value of different ultrasound methods in the diagnosis of intestinal eminence diseases, mesenteric ischemic diseases, intestinal acute abdomen, and intestinal motility disorders. Furthermore, we will discuss the disadvantages of ultrasonography in diagnosis of intestinal diseases to provide a reference for clinicians.

LigaSure compared with ligatures and endoclips in experimental appendectomy: how safe is it?

PURPOSE

The present study aims to compare strength, healing, and inflammation of appendiceal stumps closed by LigaSure Precise (Valleylab, Boulder, CO, USA) device, ligatures using polyglactin 910 (Vicryl, Ethicon, Edinburgh, UK) and endoclips (Ligaclip ERCA, Ethicon, OH, USA), and operation time (OT) in experimental appendectomy.

METHODS

Forty-eight Sprague-Dawley rats were divided into two (Group A and B). Each group was further subdivided into three subgroups (AS, AC, AL, BS, BC, BL) containing eight rats. Appendectomy was performed and stump was closed by ligatures in S, by endoclips in C and by LigaSure in L subgroups. OT was recorded. In Group A, cecum bursting pressures (BP) were determined instantly after the operation. In Group B, BP, histological evaluations, and measurements of collagen contents estimated by the tissue hydroxyproline (HPL) level were made on the seventh postoperative day. Statistical analyses were performed with Kruskal-Wallis test and Mann-Whitney U test. P value was considered significant at less than 0.05.

RESULTS

BPs of subgroups were comparable on postoperative immediate period and day 7. HPLs and OTs were significantly better in L subgroups. BL had the least inflammation.

CONCLUSION

Better healing, less inflammation, shorter OT, and equal strength achieved with LigaSure device comparing with polyglactin 910 ties and endoclips in experimental appendectomy is encouraging.