Acute appendicitis – combining history with imaging

13th February 2023, NIA Diagnostic Imaging

Acute appendicitis?

A 30 year old woman presented to her GP with a two-day history of right sided abdominal/pelvic pain. There was associated severe nausea. On examination, there was tenderness in the right lower quadrant with guarding. A pelvic ultrasound was requested.

With this request, differential diagnosis may include haemorrhagic cyst, dermoid cyst, ovarian torsion, ectopic pregnancy or endometriosis. Another differential diagnosis is acute appendicitis.

A transabdominal and a transvaginal scan were performed revealed unremarkable uterus and ovaries. The radiologist extended the scan further to look into the right iliac fossa.

At NIA Diagnostic Imaging, we ensure we provide the best service for the patient so they receive the correct treatment. As a result, the scan was reviewed in real time by the radiologist who contacted the referring doctor to discuss and organise for a CT scan. Patient was involved in the discussion and was happy to go ahead. Results from the CT scan reported the appendix is dilated measuring 12 mm and there is stranding of the fat planes. The appearances are suggestive of acute appendicitis.

Appendicitis is an inflammation of the appendix caused by the blockage of the lumen of the appendix. (Mayo Clinic, 2019) This blockage leads to an infection as bacteria builds up within the lumen. It is considered an emergency as it can rupture causing the content to enter the abdominal cavity. This is problematic as the infected matter can cause peritonitis. (Walker 2016) Another sign is free fluid (anaechoic structure with no vascularity) in pelvis or periappendiceal area. As are enlarged lymph nodes in the abdomen or mesentery. (Bickle & Jacob 2020) A fat wrap (echogenic) may be seen around the appendix correlating to inflammatory tissue and mesentry. (Radiology Nation 2008)

For appendicitis:

The appendix must have a diameter of >6mm proving dilation
With defined bowel wall layers and wall thickening of >3mm

A study by Daga et.al (2017) found the sensitivity and specificity of using ultrasound to diagnose appendicitis to be 96.5% and 85.7% with a total accuracy of 95.7%. Despite this, the appendix is not always seen on ultrasound due to factors such as large habitus, bowel gas and patient compliance. A CT scan will provide a more definitive answer with its greater sensitivity. (Bickle & Jacob 2020) In this case study, there was free fluid in the RIF, a dilated tubular structure with thickened wall and surrounding echogenic mesentery. Scanning in two planes, a blind end was seen but there was some difficulty in its confirmation as it extended deep and posteriorly.

Medical technicians have a fundamental role in patient diagnosis. It is not just about the scan or performing a protocol. It is about asking the right questions and going beyond to help answer the question. Here at NIA Diagnostic Imaging, we have qualified sonographers, radiographers and radiologists performing optimal scans to deliver accurate diagnosis and excellent patient care.

References:

Bickle, I & Jacob, K 2020, Appendicitis, Radiopaedia, viewed 21 March 2020, <https://radiopaedia.org/articles/appendicitis-2>
Daga, S, Kachewar, S, Lakhkar, DL, Jethlia, K & Itai, A 2017, Sonographic evaluation of acute appendicitis and its complications, West African Journal of Radiology, vol. 24, no. 2, pp. 152-156
Mayo Clinic 2019, Appendicitis, Mayo Clinic, viewed 02 April 2020, <https://www.mayoclinic.org/diseases-conditions/appendicitis/symptoms-causes/syc-20369543>
Radiology Nation, 2018, Ultrasound Tutorial: Appendix/Appendicitis , YouTube, 14 March, viewed 31 March 2020, <https://www.youtube.com/watch?v=PfxxVXsQsfY>
Walker, T 2016, Emergency Signs and Symptoms of Appendicitis, Healthline, viewed 30 March 2020, <https://www.healthline.com/health/digestive-health/appendicitis-emergency-symptoms>

PFO Closure

Furlan AJ, Reisman M, Massaro J, et al. Closure or medical therapy for cryptogenic stroke with patent foramen ovale. N Engl J Med 2012; 366: 991–

A multicenter, randomized, open-label trial of closure with a percutaneous device, as compared with medical therapy alone, in patients between 18 and 60 years of age who presented with a cryptogenic stroke or transient ischemic attack (TIA) and had a patent foramen ovale. The primary end point was a composite of stroke or transient ischemic attack during 2 years of follow-up, death from any cause during the first 30 days, or death from neurologic causes between 31 days and 2 years.

Results:

Primary end point was 5.5% in the closure group as compared with 6.8% in the medical-therapy group (adjusted hazard ratio, 0.78; 95% confidence interval, 0.45 to 1.35; P = 0.37)

Conclusion:

“In patients with cryptogenic stroke or TIA who had a patent foramen ovale, closure

with a device did not offer a greater benefit than medical therapy alone for the

prevention of recurrent stroke or TIA”

2 Saver JL, Carroll JD, Thaler DE, et al. Long-term outcomes of patent foramen ovale closure or medical therapy after stroke. N Engl J Med 2017; 377: 1022–

A multicenter, randomised, open-label trial ,randomly assigned patients 18 to 60 years of age who had a patent foramen ovale (PFO) and had had a cryptogenic ischemic stroke to undergo closure of the PFO (PFO closure group) or to receive medical therapy alone (aspirin, warfarin, clopidogrel, or aspirin combined with extended-release dipyridamole; medical-therapy group). The primary efficacy end point was a composite of recurrent nonfatal ischemic stroke, fatal ischemic stroke, or early death after randomisation.

Results:

Recurrent ischemic stroke occurred in 18 patients in the PFO closure group and in 28 patients in the medical-therapy group, resulting in rates of 0.58 events per 100 patient-years and 1.07 events per 100 patient years, respectively (hazard ratio 0.55; 0.31 – 0.999; P = 0.046)

Conclusion:

“Among adults who had had a cryptogenic ischemic stroke, closure of a PFO was associated with a lower rate of recurrent ischemic strokes than medical therapy alone during extended follow-up.”

Meier B, Kalesan B, Mattle HP, et al. Percutaneous closure of patent foramen ovale in cryptogenic embolism. N Engl J Med 2013; 368: 1083–

A prospective, multicenter, randomised, event-driven trial, randomly assigned patients to medical therapy alone (anti-platelet or warfarin therapy) or closure of the patent foramen ovale.

Results:

9 patients in the closure group and 16 in the medical-therapy group had a recurrence of stroke (hazard ratio with closure, 0.49; 0.22 – 1.11; P = 0.08). The primary analysis of the intentionto- treat cohort showed a nominal 51% hazard rate reduction with closure, but the reduction did not reach significance.

Conclusions:

” …there was no significant benefit associated with closure of a patent foramen ovale in adults who had had a cryptogenic ischaemic stroke.”

Sondergaard L, Kasner SE, Rhodes JF, et al. Patent foramen ovale closure or antiplatelet therapy for cryptogenic stroke. N Engl J Med 2017; 377: 1033–

Multinational trial involving patients with a PFO who had had a cryptogenic stroke, randomly assigned patients to undergo PFO closure plus antiplatelet therapy or to receive antiplatelet therapy alone.

Results:

During a median follow-up of 3.2 years, clinical ischemic stroke occurred in 6 of 441 patients (1.4%) in the PFO closure group and in 12 of 223 patients (5.4%) in the antiplatelet-only group (hazard ratio, 0.23; 0.09 to 0.62; P=0.002).

Conclusions:

“Among patients with a PFO who had had a cryptogenic stroke, the risk of subsequent ischemic stroke was lower among those assigned to PFO closure combined with antiplatelet therapy than among those assigned to antiplatelet therapy alone; however, PFO closure was associated with higher rates of device complications and atrial fibrillation.”

Mas JL, Derumeaux G, Guillon B, et al. Patent foramen ovale closure or anticoagulation vs. antiplatelets after stroke. N Engl J Med 2017; 377: 1011–

In a multicenter, randomised, open-label trial patients 16-60 years of age who had had a recent stroke attributed to PFO, to transcatheter PFO closure plus long-term antiplatelet therapy, antiplatelet therapy alone or oral anticoagulation.

Results:

No stroke occurred among patients in the PFO closure group, whereas stroke occurred in 14 of the 235 patients in the antiplatelet- only group (hazard ratio, 0.03; 0 to 0.26; P<0.001). Large number of patients discontinued anti-coagulation in the anti-coagulant group and statistical significance was not analysed because the study was not adequately powered to compare outcomes.

Conclusion:

“Among patients who had had a recent cryptogenic stroke attributed to PFO with an associated atrial septal aneurysm or large interatrial shunt, the rate of stroke recurrence was lower among those assigned to PFO closure combined with antiplatelet therapy than among those assigned to antiplatelet therapy alone. PFO closure was associated with an increased risk of atrial fibrillation.”

Lee PH, Song J-K, Kim JS, et al. Cryptogenic stroke and high-risk patent foramen ovale: the DEFENSE-PFO Trial. J Am Coll Cardiol 2018; 71: 2335–

Patients with cryptogenic stroke and high-risk PFO were divided between a transcatheter PFO closure and a medication-only group.

Results:

No events occurred in the PFO closure group. 12.9% of patients in the medication group had an event (p= 0.023).

Conclusion:

“PFO closure in patients with high-risk PFO characteristics resulted in a lower rate of the primary endpoint as well as stroke recurrence”