Abdominal wall thickness is not useful to predict appendix visualization on sonography in adult patients with suspected appendicitis

Evaluating the value of different sonographic findings in diagnosis of acute appendicitis in children

INTRODUCTION

Appendicitis is one of the most common paediatric surgical emergencies occurring in about 7% of healthy children. To make a definitive diagnosis preferably avoiding unnecessary X-ray radiation exposure, ultrasound is the ideal modality. The aim of this study is to evaluate the diagnostic value of sonographic findings in children with acute appendicitis and comparing them with surgical findings to demonstrate the safety, simplicity and accuracy of this procedure in emergency departments as the first diagnostic procedure.

MATERIALS AND METHODS

One hundred and eight children aged 1-15 years suspected of acute appendicitis in our tertiary hospital emergency department enrolled the study. Patients presenting as acute abdomen suspected as having acute appendicitis underwent abdominal ultrasonography (US) at first. Sonographic findings were compared to surgical and pathologic results, and sensitivity and specificity of each sonographic parameter in paediatric appendicitis were evaluated.

RESULTS

The analysis of sonographic results showed that 67.6% of patients had acute appendicitis, 13.9% had perforated appendicitis and 18.5% had normal appendix. On the other hand, there were acute appendicitis in 63.9% of patients, perforated appendicitis in 12% and normal appendix in 8.3% in surgical reports. Sensitivity of uncompressible appendicitis, appendicitis, maximal outer diameter (MOD) above 6 mm, maximal mural thickness (MMT) above 3 mm, round appendix was 98.68%, 28.04%, 94.74%, 61.84% and 68.42%, respectively. Specificity of incompressible appendicitis, appendicitis, MOD above 6 mm, MMT above 3 mm, round appendix was 64.71%, 96.15%, 64.71%, 82.35% and 94.12%, respectively. Overall sensitivity and specificity of US in appendicitis were 97.56% and 69.23%, respectively.

CONCLUSION

According to the findings of this study, sensitivity of US in diagnosing appendicitis is higher than other studies, but its specificity was lower. Ultrasonographic accuracy and efficacy to diagnose acute appendicitis in children are high enough to allow clinicians to do it as an imaging modality of first choice, and also, in problematic cases to assist correct clinical diagnosis avoiding unnecessary X-ray exposure, decreasing negative appendectomies, decreasing perforation rate and lowering the cost of patients. Furthermore, negative US do not justify immediate computed tomography because clinical re-evaluation and a second US can help greatly the clinicians in the correct diagnosis.

Effect of Alvarado Score on the Negative Predictive Value of Nondiagnostic Ultrasound for Acute Appendicitis

Background:

The purposes of this study were to calculate the negative predictive value (NPV) of nondiagnostic ultrasound (US) in patients with suspected appendicitis and to identify the clinical factors that were associated with the nondiagnostic US.

Methods:

We conducted a retrospective review of 412 patients who had graded-compression appendiceal US performed during January 2017 and December 2017. The NPV of the nondiagnostic US in combination with clinical parameters was calculated. Multivariate regression analysis was used to determine the independent predictors for the nondiagnostic US.

Results:

The US exam was nondiagnostic in 64.8% of the patients, giving an NPV of 70.8%. The NPV of nondiagnostic US increased to 96.2% in patients who had an Alvarado score of <5. The patients who did not have migratory pain, did not have leukocytosis, and had a pain score of <7 were more likely to have a nondiagnostic US study (P < 0.001).

Conclusion:

Alvarado score had an inverse effect on the NPV of nondiagnostic appendiceal US. Patients who had nondiagnostic US and Alvarado score of <5 were very unlikely to have appendicitis. Active clinical observation or re-evaluation rather than immediate computed tomography may be a safe alternative approach in these low-risk patients. However, the Alvarado score itself was not a predictive factor of nondiagnostic US. The absence of migratory pain, absence of leukocytosis, and low pain score were the independent predictors of nondiagnostic appendiceal US.

The importance of visualization of appendix on abdominal ultrasound for the diagnosis of appendicitis in children: A quality assessment review

BACKGROUND

Ultrasound has the first line investigation role in the diagnosis of acute appendicitis in children. The purpose of this study was to perform a quality assessment review on the visualization rate of appendix on ultrasound in children in the community hospital setting.

METHODS

A retrospective chart review of the abdominal ultrasound findings for the visualization of the appendix was performed on paediatric patients ranging from 5 to 18 years. Data were collected from the two community hospitals of Toronto by using hospital electronic medical record for the ultrasound findings in patients presented with abdominal pain.

RESULTS

Data from two community hospitals indicated visualization rate of the appendix as 11.0% and 23.2% for site 1 and site 2 respectively. In cases where the ultrasound was repeated the visualization rate remains the same. A two-proportion z-test was performed to find whether the visualization of appendix increases the likelihood of diagnosing appendicitis. The results revealed that the visualization of an appendix (P=0.52), significantly improved the diagnosis of appendicitis (z=34, P<0.001).

CONCLUSION

Visualization of an appendix on ultrasound increases the likelihood of correctly diagnosing appendicitis. In our study, we found low visualization rate of appendix on ultrasound that could be the result of many factors that contribute towards the low visualization rate of an appendix on ultrasound. Hence, the challenges in identifying appendix should be minimized to improve the visualization and diagnosis of appendicitis on ultrasound.

Correlating Abdominal Wall Thickness and Body Mass Index to Predict Usefulness of Right Lower Quadrant Ultrasound for Evaluation of Pediatric Appendicitis

OBJECTIVES

To inform selective and efficient use of appendix ultrasound (US) beyond adult parameters of body mass index (BMI) of less than 25 kg/m, we correlate abdominal wall thickness (AWT) with age and BMI to generate parameters for male and female children. Information presented in chart format can aid in the decision to utilize US for the evaluation of appendicitis.

METHODS

In this observational study, 1600 pediatric computed tomography scans of the abdomen and pelvis were analyzed to obtain measurements of AWT in the right lower quadrant. Measurements were correlated by patient age, BMI, and sex. Results and consensus-based recommendations were presented in chart format with color-coded groupings to allow for convenient referencing in the clinical setting.

RESULTS

One thousand four hundred eighty-eight computed tomography scans and AWT measurements were included. All age groups with BMI of less than 25 kg/m and all male and female groups younger than 6 years regardless of BMI had median AWT of less than 4 cm resulting in strong recommendation for US. Males older than 6 years and all female age groups with BMI of greater than 30 kg/m and female older than 15 years and BMI of greater than 25 kg/m had AWT of more than 5 cm resulting in low recommendation for US.

CONCLUSIONS

While the BMI cutoff standard of less than 25 kg/m for usefulness of appendix US holds in the adult population, our data expand the acceptable range in children younger than 9 years regardless of BMI and male children with BMI up to 30 kg/m. Female children younger than 15 years with a BMI up to 30 kg/m may also be amenable to right lower quadrant US based on AWT. These parameters inform selective and efficient use of US for appendix evaluation.

Diagnostic performance and useful findings of ultrasound re-evaluation for patients with equivocal CT features of acute appendicitis

OBJECTIVE

To evaluate the diagnostic performance of ultrasound and to determine which ultrasound findings are useful to differentiate appendicitis from non-appendicitis in patients who underwent ultrasound re-evaluation owing to equivocal CT features of acute appendicitis.

METHODS

62 patients who underwent CT examinations for suspected appendicitis followed by ultrasound re-evaluation owing to equivocal CT findings were included. Equivocal CT findings were considered based on the presence of only one or two findings among the CT criteria, and ultrasound re-evaluation was done based on a predefined structured report form. The diagnostic performance of ultrasound and independent variables to discriminate appendicitis from non-appendicitis were assessed.

RESULTS

There were 27 patients in the appendicitis group. The overall diagnostic performance of ultrasound re-evaluation was sensitivity of 96.3%, specificity of 91.2% and accuracy of 91.9%. In terms of the performance of individual ultrasound findings, probe-induced tenderness showed the highest accuracy (86.7%) with sensitivity of 74% and specificity of 97%, followed by non-compressibility (accuracy 71.7%, sensitivity 85.2% and specificity 60.6%). The independent ultrasound findings for discriminating appendicitis were non-compressibility (p = 0.002) and increased flow on the appendiceal wall (p = 0.001).

CONCLUSION

Ultrasound re-evaluation can be used to improve diagnostic accuracy in cases with equivocal CT features for diagnosing appendicitis. The presence of non-compressibility and increased vascular flow on the appendix wall are useful ultrasound findings to discriminate appendicitis from non-appendicitis. Advances in knowledge: Ultrasound re-evaluation is useful to discriminate appendicitis from non-appendicitis when CT features are inconclusive.

WSES Jerusalem guidelines for diagnosis and treatment of acute appendicitis

Acute appendicitis (AA) is among the most common cause of acute abdominal pain. Diagnosis of AA is challenging; a variable combination of clinical signs and symptoms has been used together with laboratory findings in several scoring systems proposed for suggesting the probability of AA and the possible subsequent management pathway. The role of imaging in the diagnosis of AA is still debated, with variable use of US, CT and MRI in different settings worldwide. Up to date, comprehensive clinical guidelines for diagnosis and management of AA have never been issued. In July 2015, during the 3rd World Congress of the WSES, held in Jerusalem (Israel), a panel of experts including an Organizational Committee and Scientific Committee and Scientific Secretariat, participated to a Consensus Conference where eight panelists presented a number of statements developed for each of the eight main questions about diagnosis and management of AA. The statements were then voted, eventually modified and finally approved by the participants to The Consensus Conference and lately by the board of co-authors. The current paper is reporting the definitive Guidelines Statements on each of the following topics: 1) Diagnostic efficiency of clinical scoring systems, 2) Role of Imaging, 3) Non-operative treatment for uncomplicated appendicitis, 4) Timing of appendectomy and in-hospital delay, 5) Surgical treatment 6) Scoring systems for intra-operative grading of appendicitis and their clinical usefulness 7) Non-surgical treatment for complicated appendicitis: abscess or phlegmon 8) Pre-operative and post-operative antibiotics.

How to diagnose acute appendicitis: ultrasound first

Acute appendicitis (AA) is a common abdominal emergency with a lifetime prevalence of about 7 %. As the clinical diagnosis of AA remains a challenge to emergency physicians and surgeons, imaging modalities have gained major importance in the diagnostic work-up of patients with suspected AA in order to keep both the negative appendectomy rate and the perforation rate low. Introduced in 1986, graded-compression ultrasound (US) has well-established direct and indirect signs for diagnosing AA. In our opinion, US should be the first-line imaging modality, as graded-compression US has excellent specificity both in the paediatric and adult patient populations. As US sensitivity is limited, and non-diagnostic US examinations with non-visualization of the appendix are more a rule than an exception, diagnostic strategies and algorithms after non-diagnostic US should focus on clinical reassessment and complementary imaging with MRI/CT if indicated. Accordingly, both ionizing radiation to our patients and cost of pre-therapeutic diagnosis of AA will be low, with low negative appendectomy and perforation rates.

Main Messages

• Ultrasound (US) should be the first imaging modality for diagnosing acute appendicitis (AA).

• Primary US for AA diagnosis will decrease ionizing radiation and cost.

• Sensitivity of US to diagnose AA is lower than of CT/MRI.

• Non-visualization of the appendix should lead to clinical reassessment.

• Complementary MRI or CT may be performed if diagnosis remains unclear.

Usefulness of Ultrasonography for Diagnosis of Small Bowel Tumors: A Comparison Between Ultrasonography and Endoscopic Modalities

Ultrasonography is a standard, noninvasive modality used to evaluate patients with gastrointestinal diseases. This study assessed the usefulness of ultrasonography in the detection of small bowel tumors. This study enrolled 558 consecutive patients (295 males, 263 females; mean age 71.1 years) who underwent ultrasonography before capsule endoscopy and/or balloon-assisted endoscopy. Ultrasonographic detection of small bowel tumors was compared with detection by capsule endoscopy and/or balloon-assisted endoscopy. In addition, factors affecting small bowel tumor detection by ultrasonography and clinical characteristics of patients with small bowel tumors undetected by ultrasonography were evaluated. Ninety-seven tumors (52 benign, 45 malignant) detected by capsule endoscopy and/or balloon-assisted endoscopy were retrospectively analyzed. The sensitivity and specificity of ultrasonography in the detection of small bowel tumors were 50.5% (47/93) and 100% (465/465), respectively. If we restricted patients to those with a tumor >20 mm in size, its detection ratio would become higher (91.7%): the ratio of submucosal tumor >20 mm in size was 85.7% (6/7) and that of partial and circumferential ulcerative tumors >20 mm in size was 96.9% (31/32), respectively. Small bowel tumors detected by ultrasonography (mean 33.2 mm) were significantly larger than those undetected by ultrasonography (mean 8.7 mm). The percentage of small bowel tumors located in the ileum detected by ultrasonography (70.6%) was significantly higher than those undetected by ultrasonography (29.4%). Of the 46 small bowel tumors undetected by ultrasonography, 42 (91.3%) were benign tumors with good clinical prognosis. Ultrasonography is a useful modality for detecting larger small bowel tumors and ulcerative lesions. Ultrasonography should be considered a first-line modality for patients suspected of having small bowel tumors, because most small bowel tumors undetected by ultrasonography were benign tumors with good clinical prognosis.