Medical Imaging for Suspected Appendicitis

December 20, 2017 – 6 min read

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Accurate and speedy diagnosis of appendicitis, an inflammation of the appendix, is essential however many times the classical symptoms as described below may not be present, presenting the treating doctor with a dilemma. Before advanced imaging such as CT and ultrasound, the doctor had to make a decision as best he or she could. This resulted in the surgical removal of many normal appendices as other, less serious, disorders can mimic the symptoms of appendicitis. In fact, doctors were taught that if 25% of removed appendices weren’t normal, then too few surgeries were being done!  With the advent of medical imaging, the diagnosis of appendicitis has been substantially advanced to where it is rare to not be scanned when the symptoms may suggest appendicitis. There are several different medical imaging options to consider, including MRI, CT scan, and ultrasound. While CT scans have been the standard for children in the past, ultrasound can also have a high degree of accuracy in confirming appendicitis and does not expose the child to radiation. Recent research has also indicated that MRI is just as accurate as CT in appendicitis confirmation. MRI also is without radiation but is more costly by a factor of 2.

What Is Appendicitis?

The appendix is a small long pouch that extends off the beginning part of the large intestine. Usually only 2-4 inches long, we still don’t know exactly what the appendix does, but it may have something to do with gut immunity. What we do know is that when the appendix becomes inflamed or infected it must usually be removed although recent research suggests that many patients can be treated only with antibiotics and no surgery but with some having repeated symptoms and then possible surgery.

When the appendix becomes obstructed, either by stool,  tumor, or foreign object, infection occurs in the “dammed up” appendix with subsequent swelling of the appendix. If it continues to swell, it will eventually burst with the pent up infection spilling into the abdominal cavity resulting in peritonitis—a dangerous inflammation of the abdominal cavity requiring intensive antibiotic therapy. Appendicitis can be fatal and is considered an emergency situation. While appendicitis can occur at any age, it is most common between the ages of 10 and 30, affects 80,000 children a year in the United States, and is the most common reason for pediatric emergency abdominal surgery. Ruptured appendicitis is found in 30 percent of these patients, and is most common under five years old. Appendicitis presents with the following symptoms:

  • Pain: The most common symptom of appendicitis is severe pain that presents in the lower right abdomen.
  • Swelling: Tenderness and swelling of the abdomen.
  • Nausea: Both nausea and vomiting may occur after abdominal pain, and may come in waves.
  • Fever: A high fever, over 100 degrees.
  • Intestinal Problems: Diarrhea, constipation, or an inability to expel gas may be present.

Many of these symptoms can be present in other medical conditions, but it is the constant pain on the lower right side of the abdomen that usually is present and is a strong indication of appendicitis. Once appendicitis is suspected, medical imaging is used to confirm.

Medical Imaging for Pediatric Appendicitis

An initial ultrasound can be used to detect appendicitis, an ultrasound is usually a readily available, affordable choice for medical imaging. Combined with an Alvarado score, which assigns a score for symptoms including fever, pain, and elevated white blood cells in the blood, ultrasound can be a conservative imaging choice. In non-emergency cases, combining ultrasound and Alvarado scores and monitoring both can be effective in appendicitis diagnosis, and can eliminate the need for further imaging. And while ultrasound is useful, it has its limitations and can be hindered by variation in the varying technical skills of sonographers as well as patient obesity and the child’s ability and willingness to lie still. And when the diagnosis is not clear, or in emergency cases, more conclusive imaging is needed. CT scans have been the standard imaging methodology used to confirm appendicitis in children, but new research is showing that MRI is just as useful. In a study involving 48 patients between the ages of 12 and 20 years old who presented with abdominal pain, it was concluded that the accuracy of MRI and CT scans in diagnosing acute appendicitis was very similar. The percentages for sensitivity and specificity were between 85.0 and 93.8 for unenhanced MRI, 93.6 and 94.3 for contrast-enhanced MRI, and 93.6 and 94.3 for CT. An unenhanced MRI avoids the need for IV contrast, and also eliminates the radiation exposure present with CT scans. Another study done in 2015 found similar results, and concluded that “MRI has high sensitivity and specificity for appendicitis in pediatric patients with inconclusive ultrasound.”  An MRI, especially for young patients, eliminates the risk of radiation exposure that a CT scan has, and with the findings pointing to similar accuracy as CT scans, MRI is becoming the choice for appendicitis detection. If the child does have a CT done, modern techniques, inspired in part by the national “Image Gently” program of which Touchstone Imaging is a member, minimize the radiation dose to him or her.

Appendicitis Treatment

While no single test can diagnose appendicitis conclusively 100 percent of the time, the information gathered through physical examination, bloodwork, and the right medical imaging allows physicians to make informed conclusions. If appendicitis is suspected, surgery is usually the next step. An anesthesiologist will put your child to sleep, and the appendix will be removed, usually laparoscopically. If the appendix has already ruptured, surgery is usually done after antibiotic treatment and the infected fluid will be washed out of the abdominal cavity, and drains are sometimes placed as well. While pediatric appendicitis is a scary and serious situation, children usually recover quickly from uncomplicated disease and have no long-lasting complications.

Medical imaging plays a central role in the diagnosis of appendicitis, and new research is pointing toward MRI as the choice for pediatric cases. Touchstone Imaging is proud to offer high field MRI at many of our locations in Texas, Colorado, Oklahoma, Nebraska, Florida, and Arkansas. If you suspect appendicitis in your child, see a doctor as soon as possible, and know that Touchstone Imaging is the trusted choice for quality and affordable MRI in a caring environment.