The Optimization of a Low-dose CT Protocol in Patients With Suspected Uncomplicated Acute Appendicitis and BMI >30 (OPTICAP>30)

Turku University Hospital (TYKS)

Status: Suspended

Conditions: Intra-abdominal Infection; Gastrointestinal Disease; Appendicitis; Acute Disease; Other and Unspecified Acute Appendicitis

Treatments: Radiation: Low-dose CT; Procedure: Laparoscopic appendectomy

Study type: Interventional

Funder types: Other

Identifiers

NCT04519086

OPTICAP BMI >30kg/m2

Details and patient eligibility

About

This study focuses on the use of contrast enhanced low-dose CT imaging as a modality to differentiate between uncomplicated and complicated acute appendicitis. Accurate differential diagnosis allows the assessment of all available treatment options. Complicated acute appendicitis requires emergency appendectomy, while uncomplicated acute appendicitis can be safely and efficiently treated with antibiotics in the majority of patients. Our study group already published the results of the initial OPTICAP trial enrolling patients with BMI under 30 showing similar accuracy between the low-dose and the stadard dose CT, but a significant dose reduction associated with the low-dose CT. All patients will undergo both imaging protocols as the standard CT is also optimized for a low as possible radiation dosage and imaging sequence per patient is randomized due to the optimization of contrast media injection timing. All patients participating in this study will be treated operatively with a laparoscopic appendectomy to obtain histological confirmation for the diagnosis to evaluate the accuracy of the CT imaging. The aim of this study is to optimize a well-performing low-dose CT imaging protocol to use in the diagnosis of uncomplicated acute appendicitis in patients with body mass index over 30 kg/m2.

Full description

Acute appendicitis is one of the most common causes of abdominal pain in emergency departments as well as one of the most common indications for emergency abdominal surgery. The clinical diagnosis has been based on patient history, physical examination and laboratory findings as well as the "clinical eye" of the surgeon. Still the diagnosis remains challenging. One of the main problems is that many other disorders can mimic the clinical presentation of appendicitis, thus increasing the role of imaging techniques to aid in diagnostic accuracy. Now preoperative imaging in patients with suspected acute appendicitis is currently widely accepted as the gold standard and CT has been shown to clearly outperform US in terms of diagnostic performance. Currently CT imaging is considered the primary imaging modality in the diagnosis for acute appendicitis as it is appraised for its high sensitivity and specificity. The main disadvantage of CT imaging is exposure to radiation. Thus the favorable diagnostic performance of CT imaging has encouraged optimization of protocols to minimize exposure to radiation through the development of low-dose CT protocols. Initial studies have indicated that contrast enhanced low-dose CT was not inferior to standard-dose contrast enhanced CT with no statistical significance in negative appendectomy rates, appendiceal perforation rates or patients requiring additional imaging.

This study focuses on the use of contrast enhanced low-dose CT imaging as a modality to differentiate between uncomplicated and complicated acute appendicitis in patients with BMI over 30 kg/m2. Accurate differential diagnosis allows the assessment of all available treatment options. Complicated acute appendicitis requires emergency appendectomy, while uncomplicated acute appendicitis can be safely and efficiently treated with antibiotics in the majority of patients. Our study group already published the results of the initial OPTICAP trial enrolling patients with BMI under 30 showing similar accuracy between the low-dose and the stadard dose CT, but a significant dose reduction associated with the low-dose CT. All patients will undergo both imaging protocols as the standard CT is also optimized for a low as possible radiation dosage and imaging sequence per patient is randomized due to the optimization of contrast media injection timing. All patients participating in this study will be treated operatively with a laparoscopic appendectomy to obtain histological confirmation for the diagnosis to evaluate the accuracy of the CT imaging. The aim of this study is to optimize a well-performing low-dose CT imaging protocol to use in the diagnosis of uncomplicated acute appendicitis in patients with body mass index over 30 kg/m2.

Enrollment: 30 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age 18-60 years
• Clinical suspicion of acute uncomplicated appendicitis based on history, physical examination, laboratory findings evaluated by a senior surgeon
• Body mass index over 30 kg/m2

Exclusion criteria

• Age <18 years or > 60 years
• Pregnancy or breastfeeding
• Allergy to contrast material or iodine
• History of appendectomy
• Renal failure, creatinine-value greater than the upper reference value
• Diabetes mellitus and metformin medication
• Suspicion of peritonitis and appendiceal perforation
• Incapability to cooperate and give consent to participate in the study

Trial design

Primary purpose: Diagnostic

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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30 participants in 1 patient group

Low-dose CT for acute appendicitis in patients with BMI >30

Experimental group

Description:

Low-dose computed tomography (CT) vs. standard CT for diagnosing acute uncomplicated appendicitis in patients with BMI \> 30 Laparoscopic appendectomy

Treatment:

Procedure: Laparoscopic appendectomy

Radiation: Low-dose CT