The utility of CT scan for the diagnostic evaluation of acute abdominal pain

To Scan or Not to Scan: Development of a Clinical Decision Support Tool to Determine if Imaging Would Aid in the Diagnosis of Appendicitis

BACKGROUND

Appendicitis is one of the most common surgically treated diseases in the world. CT scans are often over-utilized and ordered before a surgeon has evaluated the patient. Our aim was to develop a tool using machine learning (ML) algorithms that would help determine if there would be benefit in obtaining a CT scan prior to surgeon consultation.

METHODS

Retrospective chart review of 100 randomly selected cases who underwent appendectomy and 100 randomly selected controls was completed. Variables included components of the patient's history, laboratory values, CT readings, and pathology. Pathology was used as the gold standard for appendicitis diagnosis. All variables were then used to build the ML algorithms. Random Forest (RF), Support Vector Machine (SVM), and Bayesian Network Classifiers (BNC) models with and without CT scan results were trained and compared to CT scan results alone and the Alvarado score using area under the Receiver Operator Curve (ROC), sensitivity, and specificity measures as well as calibration indices from 500 bootstrapped samples.

RESULTS

Among the cases that underwent appendectomy, 88% had pathology-confirmed appendicitis. All the ML algorithms had better sensitivity, specificity, and ROC than the Alvarado score. SVM with and without CT had the best indices and could predict if imaging would aid in appendicitis diagnosis.

CONCLUSION

This study demonstrated that SVM with and without CT results can be used for selective imaging in the diagnosis of appendicitis. This study serves as the initial step and proof-of-concept to externally validate these results with larger and more diverse patient population.

Serum Soluble CD40 Ligand in Predicting Simple Appendicitis and Complicated Appendicitis at Different Time Points in Children

Objectives: Appendicitis is a common abdominal emergency in children. It is difficult for clinicians to distinguish between simple appendicitis (SA), gangrenous appendicitis (GA), and ruptured appendicitis (RA) in children based on physical and current laboratory tests. Abdominal computed tomography with the disadvantage of excess radiation exposure is usually used in the emergency room for appendicitis surveys. Serum soluble CD40 ligand (sCD40L) is an inflammatory biomarker. This study aimed to use sCD40L to distinguish SA, GA, and RA. Methods: All patients aged <18 years old with suspected appendicitis were tested once for serum sCD40L within 72 h of appendicitis symptoms. We compared sCD40L levels of SA, GA, and RA individually on days 1, 2, and 3 in patients with normal appendix (NA), a total of nine subgroups. Thereafter, the diagnostic performance of sCD40L in predicting appendicitis and the receiver operating characteristic curves were carried out. Results: Of 116 patients, 42 patients had SA, 20 GA, 44 RA, and 10 NA. We found six subgroups with significant p-values of sCD40L predicting appendicitis as follows: SA on day 2, GA on days 2 and 3, and RA on days 1-3. The sensitivity and specificity of sCD40L at the best cutoff point with 178 pg/mL in these six subgroups range from 0.75 to 1.00 and 0.90, respectively. Conclusions: SCD40L is a good predictor of pediatric appendicitis. Clinicians can use sCD40L to distinguish from SA, GA, and RA in children with suspected appendicitis.

Noncontrast MRI of acute abdominal pain caused by gastrointestinal lesions: indications, protocol, and image interpretation

Gastrointestinal tract lesions are major causes of acute abdominal pain. A rapid, accurate, and reliable diagnosis is required to manage patients. Magnetic resonance imaging (MRI) is a nonionizing modality that is beneficial for pregnant women, children, and young adults who are sensitive to ionizing radiation. For patients with renal impairment who are not accurately diagnosed with noncontrast computed tomography, noncontrast MRI can serve as an alternative diagnostic modality. MRI protocols used for acute abdominal pain are supposed to be optimized and prioritized to shorten scanning times. Single-shot T2-weighted and fat-suppressed T2-weighted imaging are important pulse sequences that are used to reveal pathology and inflammation in the gastrointestinal tract. Diffusion-weighted imaging clearly depicts inflammation and abscesses as hyperintense lesions. Most acute gastrointestinal tract lesions, including inflammation, ischemia, obstruction, and perforation, demonstrate bowel wall thickening. Bowel obstruction and adynamic ileus present bowel dilatation, and perforation and penetration show bowel wall defects. MRI can be used to reveal these pathological findings with some characteristics depending on their underlying pathophysiology. This review article discusses imaging modalities for acute abdominal pain, describes a noncontrast MRI protocol for acute abdominal pain caused by gastrointestinal tract lesions, and reviews MRI findings of acute gastrointestinal tract lesions.

Reliability of standardized reporting system of acute appendicitis in adults at low-dose 320-rows CT

Aim

To assess the reliability of a standardized reporting system of acute appendicitis at low-dose 320-rows CT.

Subjects and Methods

Retrospective analysis CT of 78 patients with pathologically proven acute appendicitis. The study was performed at a low-dose 320-rows CT. The image analysis was performed by 2 radiologists according to a standardized reporting system of acute appendicitis.

Results

There was an excellent overall of the inter-observer agreement of both observers for the standardized reporting system of acute appendicitis (K = 0.89, 95 % CI = 0.87-0.92, P = 0.001). There was good inter-observer agreement for visualization of the appendix (K = 0.78, P = 0.001), the tip diameter (K = 0.75, P = 0.001), and a single wall thickness of appendix (K = 0.77, P = 0.001). There was excellent inter-observer agreement for outer to outer wall diameter (K = 0.82, P = 0.001), mucosal hyper-enhancement (K = 0.80, P = 0.001), appendicolith (K = 0.86, P = 0.001), gas in the appendix (K = 0.82, P = 0.001), surrounding fat stranding (K = 0.81, P = 0.001), focal cecal thickening (K = 0.85, P = 0.001), peri-appendiceal air (K = 0.87, P = 0.001), peri-appendicular fluid collection, phlegmon, or abscess (K = 0.82, P = 0.001), and right ovary cyst (K = 0.83, P = 0.001).

Conclusion

we concluded that excellent reliability of a standardized reporting system of acute appendicitis in the adults using low-dose 320-rows CT.