- “ Preoperative MDCT generally allows for efficient and confident inclusion or exclusion of appendicitis, resulting in reduced rates of perforation and negative findings at appendectomy, as well as providing an alternative explanation in many cases without appendicitis.”
Diagnostic Performance of Multidetector Computed Tomography for Suspected Acute Appendicitis
Pickhardt PJ et al.
Ann Intern Med 2011;154:789-796 - “ 675 of 2871 (23.5%) had confirmed acute appendicitis. The sensitivity, specificity, and negative and positive predictive values of MDCT were 98.5%, 98.0%, 99.5% and 93.9% respectively.”
Diagnostic Performance of Multidetector Computed Tomography for Suspected Acute Appendicitis
Pickhardt PJ et al.
Ann Intern Med 2011;154:789-796 - “ 675 of 2871 (23.5%) had confirmed acute appendicitis. The sensitivity, specificity, and negative and positive predictive values of MDCT were 98.5%, 98.0%, 99.5% and 93.9% respectively. The overall negative findings at appedectomy was 7.5% but would have been decreased to 4.1% had surgery been avoided in 26 cases with true negative findings on MDCT.”
Diagnostic Performance of Multidetector Computed Tomography for Suspected Acute Appendicitis
Pickhardt PJ et al.
Ann Intern Med 2011;154:789-796 - “The overall negative findings at appedectomy was 7.5% but would have been decreased to 4.1% had surgery been avoided in 26 cases with true negative findings on MDCT.”
Diagnostic Performance of Multidetector Computed Tomography for Suspected Acute Appendicitis
Pickhardt PJ et al.
Ann Intern Med 2011;154:789-796 - “Multidetector computed tomography provided or suggested an alternative diagnosis in 893 of 2122 patients (42.1%) without appendicitis or appendectomy.”
Diagnostic Performance of Multidetector Computed Tomography for Suspected Acute Appendicitis
Pickhardt PJ et al.
Ann Intern Med 2011;154:789-796 "Five of 13 patients with CT findings of appendicitis and reassuring clinical evaluation results in whom immediate treatment was deferred ultimately returned with appendicitis. In patients with CT results positive for appendicitis and benign or atypical clinical findings, a diagnosis of chronic or recurrent appendicitis may be considered." Acute Appendicitis: Clinical Outcomes in Patients with an Initial False Positive CT Diagnosis
Stengel JW et al.
Radiology 2010; 256:119-126 Implications for Patient Care "The decision to forego surgery in patients with CT findings compatible with appendicitis but reassuring surgical evaluation findings often results in missed appendicitis and increased risk of perforation." Acute Appendicitis: Clinical Outcomes in Patients with an Initial False Positive CT Diagnosis
Stengel JW et al.
Radiology 2010; 256:119-126 "As radiologists, radiation protection is one of our primary concerns, as we also ensure that each patient recieves the most accurate examination for the clinical problem. Radiation exposure is reduced by judicious and appropriate use if imaging modalities; in our quest to reduce stochastic risks, unnecessary surgery and a ruptured appendix are not the most appropriate alternatives." CT and US in the Diagnosis of Appendicitis: An Argument for CT
Hernanz-Schulman,M
Radiology 2010; 255:3-7 "In conclusion, in patients presenting with acute nontraumatic abdominal pain, there is no statistically significant difference in specificity for diagnosing appendicitis identified in our study between CT scans obtained after the administration of oral and IV contrast media versus those obtained with the use of only IV contrast material." Abdominal 64-MDCT for Suspected Appendicitis: The Use of Oral and IV Contrast Material Versus IV Contrast Material Only
Anderson SW et al.
AJR 2009; 193:1282-1288 "Patients presenting with nontraumatic abdominal pain imaged using 64-MDCT with isotropic reformations had similar characteristics for the diagnosis of appendicitis when IV contrast material alone was used and when oral and IV contrast media was used." Abdominal 64-MDCT for Suspected Appendicitis: The Use of Oral and IV Contrast Material Versus IV Contrast Material Only
Anderson SW et al.
AJR 2009; 193:1282-1288 "Visualization of the appendix depended predominately on the reader rather than on the use of IV, oral, or oral and IV contrast agents or on radiation dose." MDCT for Suspected Acute Appendicitis in Adults: Impact of Oral and IV Contrast Media at Syandard Dose and Simulated Low Dose Techniques
Heyzer C et al.
AJR 2009; 193:1272-1281 "Diagnostic correctness is much more influenced by the reader than by the use of contrast medium (oral,IV, or both) or of simulated low dose radiation technique." MDCT for Suspected Acute Appendicitis in Adults: Impact of Oral and IV Contrast Media at Syandard Dose and Simulated Low Dose Techniques
Heyzer C et al.
AJR 2009; 193:1272-1281 "The decision to forego surgery in patients with CT findings compatible with appendicitis but reassuring surgical evaluation findings often results in missed appendicitis and increased risk of perforation." Acute Appendicitis: Clinical Outcome in Patients with an Initial False-Positive Diagnosis
Stengel JW et al
Radiology 2010: 000:1-8 "Five of 13 patients with CT findings of appendicitis and reassuring clinical evaluation results in whom immediate treatment was deferred ultimately returned with appendicitis.In patients with CT results positive for appendicitis and benign or atypical clinical findings a diagnosis of chronic or recurrent appendicitis may be considered." Acute Appendicitis: Clinical Outcome in Patients with an Initial False-Positive Diagnosis
Stengel JW et al
Radiology 2010: 000:1-8 - What if the CT scan suggests appendicitis but the surgeon says the patient does not? Who is going to be correct?
- The surgeon
- The radiologist
- No one consistantly "While appendicitis could undoubtedly occur in an isodense appendix between 6 and 10 mm in diameter, such an appearance can occur in up to 6.6% of the normal population." The equivocal appendix at CT: prevalence n a control population
Webb EM et al.
Emerg Radiol (2010) 17;57-61 "In summary, our study found that while the outer wall-to-outer wall diameter of the normal appendix is frequently greater than 6 mm, none had a diameter greater than 10 mm in combination with equivocal mophology." The equivocal appendix at CT: prevalence n a control population
Webb EM et al. Emerg Radiol (2010) 17;57-61 "Rising utilization of preoperative CT and advances in technology coincided with a decrease in the negative appendectomy rate for woman 45 years and younger but not in men of any age or woman older than 45 years." Making the Diagnosis of Acute Appendicitis: Do More Preoperative CT Scans Mean Fewer Negative Appendectomies? A 10-year Study
Coursey CA et al.
Radiology 2010; 254:460-468 "We believe our study, along with the results of prior studies, supports the use of preoperative CT particularly in the evaluation of woman of reproductive age suspected of having acute appendicitis." Making the Diagnosis of Acute Appendicitis: Do More Preoperative CT Scans Mean Fewer Negative Appendectomies? A 10-year Study
Coursey CA et al.
Radiology 2010; 254:460-468 "The percentage of patients undergoing CT prior to appendectomy increased from 18.5% (10 of 54) in 1998 to 94.2% (97 of 103) in 2007." Making the Diagnosis of Acute Appendicitis: Do More Preoperative CT Scans Mean Fewer Negative Appendectomies? A 10-year Study
Coursey CA et al.
Radiology 2010; 254:460-468 "As preoperative CT use increased, the negative appendectomy rate in woman 45 years of age and younger decreased from 42.9% to 7.1%." Making the Diagnosis of Acute Appendicitis: Do More Preoperative CT Scans Mean Fewer Negative Appendectomies? A 10-year Study
Coursey CA et al.
Radiology 2010; 254:460-468 "The improved confidence in visualizing appendiceal and periappendiceal findings eventually resulted in increased confidence in diagnosing appendicitis."
MDCT with Coronal Reconstruction: Clinical Benefit in Evaluation of Suspected Acute Appendicitis in Pediatric Patients
Kim YJ et al
AJR 2009; 192:150-152 "In pediatric patients with suspected appendicitis, the addition of coronal reformatted scans to axial images in MDCT increases confidence in the diagnosis or exclusion of acute appendicitis."
MDCT with Coronal Reconstruction: Clinical Benefit in Evaluation of Suspected Acute Appendicitis in Pediatric Patients
Kim YJ et al
AJR 2009; 192:150-152 "If workstation and network constraints limit a departments capacity to manage 2x1 mm sections, the study results indicate that the thinnest feasible sections (e.g.3x3 mm rather than 5x5 mm) should be used for the best possible interpretive confidence."
MDCT for Suspected Appendicitis: Effect of reconstruction Section Thickness on Diagnostic Accuracy, Rate of Appendiceal Visualization, and Reader Confidence using Axial Images
Johnson PT, Horton KM, Kawamoto S et al.
AJR 2009; 192:893-901 "Correctness of diagnosis was not significantly associated with reconstruction method. However, for correctly diagnosed cases as normal, impression confidence increased with progressively thinner section thickness (p<0.001 for 5x5 vs 3x3 and 3x3 vs 2x10)."
MDCT for Suspected Appendicitis: Effect of reconstruction Section Thickness on Diagnostic Accuracy, Rate of Appendiceal Visualization, and Reader Confidence using Axial Images
Johnson PT, Horton KM, Kawamoto S et al.
AJR 2009; 192:893-901 - "Medical literature (from 1986-2004) were searched for articles on studies that used US,CT or both as diagnostic tests for appendicitis in children (26 studies, 9356 participants) or adults (31 studies, 4341 participants)."
US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta Analysis Doria AS et al Radiology 2006; 241:83-94 - "From the diagnostic performance perspective, CT had a significantly higher sensitivity than did US in studies of children and adults; from the safety perspective, however, one should consider the radiation associated with CT, especially in children."
US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta Analysis
Doria AS et al
Radiology 2006; 241:83-94 - "CT has a significantly higher sensitivity than does US for the diagnosis of appendicitis in adults and children; we should note that the sensitivity of US is reasonably high in children and that radiation issues are of special concern in this age group."
US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta Analysis
Doria AS et al
Radiology 2006; 241:83-94 - "Pooled sensitivity and specificity for diagnosis of appendicitis in children were 88% and 94%, respectively, for US studies and 94% and 95% respectively for CT studies."
US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta Analysis
Doria AS et al
Radiology 2006; 241:83-94 - "Pooled sensitivity and specificity for diagnosis of appendicitis in adults were 83% and 93%, respectively, for US studies and 94% and 94% respectively for CT studies."
US or CT for Diagnosis of Appendicitis in Children and Adults? A Meta Analysis
Doria AS et al
Radiology 2006; 241:83-94 - "Unenhanced focused single detector CT and graded compression sonography performed in a general community teaching hospital by both body imaging radiologists and general radiology staff members have a similar accuracy for the diagnosis of acute appendicitis."
Comparison of CT and Sonography in the Diagnosis of Acute Appendicitis: A Blinded Perspective Study
Poortman P et al.
AJR 2003:181:1355-1359 - "147 patients had acute appendicitis at surgery and 67 patients did not. The sensitivity of CT and sonography were 76% and 79% respectively; the specificity was 83% and 78%, the accuracy was 78% and 78%."
Comparison of CT and Sonography in the Diagnosis of Acute Appendicitis: A Blinded Perspective Study
Poortman P et al.
AJR 2003:181:1355-1359 - Comparison of CT and Sonography in the Diagnosis of Acute Appendicitis: A Blinded Perspective Study
Poortman P et al.
AJR 2003:181:1355-1359
noted limitations of this study: this study used a single detector scanner with 5 mm x 5 mm protocol and no oral, IV or rectal contrast - "In conclusion, this review illustrates the sonographic and CT features of a broad spectrum of nonsurgical diseases that may clinically present as appendicitis in patients without appendicitis. A correct imaging diagnosis of these alternative disorders may have a major impact on patient management because it prevents an unnecessary operation or hospitalization."
Mimics of Appendicitis: Alternative Nonsurgical Diagnoses with Sonography and CT
van Breda Vriesman et al
AJR 2006;186:1103-1112 - "In conclusion, this review illustrates the sonographic and CT features of a broad spectrum of nonsurgical diseases that may clinically present as appendicitis in patients without appendicitis."
Mimics of Appendicitis: Alternative Nonsurgical Diagnoses with Sonography and CT
van Breda Vriesman et al
AJR 2006;186:1103-1112 - GI Mimics of Appendicitis
- Mesenteric adenitis
- Infectious enterocolitis
- Epiploic appendages
- Omental infarction
- Right sided diverticulitis
- Crohns disease
- Meckels divericulum
- Ileocecal intussuception - Non-GI Mimics of Appendicitis
- Pelvic inflammatory disease
- Renal or ureteral stone disease
- Rectus hematoma
- Psoas abscess or hematoma - "Mortality and morbidity rates for removal of a normal appendix are 0.14% and 4.6%, respectively,but increase to 0.24% and 6.1% for acute appendicitis and up to 1.7% and 19% for perforated appendicitis."
CT and Sonography for Suspected Acute Appendicitis: A Commentary
Jacobs JE
AJR 2006;1861094-1096 - "The current accepted negative laparotomy rate is 10-15% but negative laparotomy rates can be much higher in woman of child bearing age."
CT and Sonography for Suspected Acute Appendicitis: A Commentary
Jacobs JE
AJR 2006;1861094-1096 - "There was no significant difference between the performance of intravenous contrast enhanced CT and that of rectal and intravenous enhanced CT in children suspected of having appendicitis."
Suspected Appendicitis in Children: Rectal and Intravenous Contrast-enhanced versus Intravenous Contrast-enhanced CT
Kharbanda AB et al. - "Intravenous and rectal contrast enhanced CT had a sensitivity of 92%, a specificity of 87%, a negative predictive value of 94% and an accuracy of 89%.Intravenous contrast enhanced CT had a sensitivity of 93%, a specificity of 92%, a negative predictive value of 95%, and an accuracy of 92%."
Suspected Appendicitis in Children: Rectal and Intravenous Contrast-enhanced versus Intravenous Contrast-enhanced CT
Kharbanda AB et al. - "Intravenous contrast enhanced CT had a sensitivity of 93%, a specificity of 92%, a negative predictive value of 95%, and an accuracy of 92%."
Suspected Appendicitis in Children: Rectal and Intravenous Contrast-enhanced versus Intravenous Contrast-enhanced CT
Kharbanda AB et al. - "Acute appendicitis is one of the most common causes of acute abdominal pain, the most common condition that requires abdominal surgery in childhood, and the most common condition associated with lawsuits among emergency physicians."
CT Evaluation of Appendicitis and Its Complications:Imaging Techniques and Key Diagnostic Findings
Leite NP et al.
AR 2005;185:406-417 - Ultrasound and Appendicitis
- Success dependent on skill of operator
- Difficult in large patients
- Difficult if patient is in pain or uncooperative
- May not define normal appendix or perforated appendix (both at extreme of appearances) - CT Protocols for Appendicitis
- Unenhanced CT (no oral, no IV contrast)
- Oral contrast only
- IV contrast only
- Oral and IV contrast
- Rectal contrast only
- Rectal contrast w/ oral and/or IV contrast - How are CT scans for suspected appendicitis reviewed?
- Axial images
- Multiplanar images (especially coronal display)
- 3D images (mainly VRT) - "The sensitivity for diagnosing appendicitis based on the coronal images alone was 96%, the specificity was 100% and the accuracy was 98%. Coronal reformations decreased the number of images by 19%. CT diagnosis of appendicitis based on the coronal images is accurate."
MDCT diagnosis of appendicitis using only coronal reformations
Yaghmai V et al.
Emerg Radiol (2007) 14:167-172 (4MDCT Scanner) - "The sensitivity for diagnosing appendicitis based on the coronal images alone was 96%, the specificity was 100% and the accuracy was 98%. CT diagnosis of appendicitis based on the coronal images is accurate."
MDCT diagnosis of appendicitis using only coronal reformations
Yaghmai V et al.
Emerg Radiol (2007) 14:167-172 (4MDCT Scanner) - Appendicitis:Complications
- Perforation- more common in patients with appendoliths as appendoliths seem to increase probability of perforation
- Periappendiceal abscess- most frequent complication of perforation
- Peritonitis- more common in younger patients - Appendicitis:Complications
- Bowel obstruction
- Septic seeding of mesenteric vessels
- Gangrenous appendicitis
- CT Evaluation of Appendicitis and Its Complications:Imaging Techniques and Key Diagnostic FindingsLeite NP et al.AR 2005;185:406-417 - "Although certain multidetector CT findings are very specific for the diagnosis of perforated appendicitis, overall multidetector CT sensitivity is poor. Unless abscess or extraluminal gas is present, multidetector CT cannot enable the diagnosis of perforation."
Perforated versus Nonperforated Acute Appendicitis: Accuracy of Multidetector CT Detection
Bixby SD et al.
Radiology 2006;241:780-786 - CT Findings of Perforated Appendix
- Extraluminal gas
- Abscess
- Small bowel ileus
- Peritonitis
- Appendicolith
- Free fluid
- Mesenteric lymph nodes
- Cecal wall thickening - CT Findings of Perforated Appendix with Specificity of greater than 90%
- Extraluminal gas
- Abscess
- Small bowel ileus
- Peritonitis
- Appendicolith
- Free fluid
- Mesenteric lymph nodes
- Cecal wall thickening - Mucocele of the Appendix: facts
- Well capsulated cystic mass in the pericecal region which is the distended appendiceal lumen caused by abnormal mucous accumulation
- The mass may contain calcifications and enhance with IV contrast material - "Sensitivity of helical CT for suspected appendicitis in children improved significantly with abdominal contrast enhanced CT compared with limited area non-enhanced CT."
Suspected Appendicitis in Children: Diagnosis with Contrast-enhanced versus Nonenhanced Helical CT
Kaiser S et al.
Radiology 2004;231:427-433 - "Sensitivity of helical CT for suspected appendicitis in children improved significantly with abdominal contrast enhanced CT compared with limited area non-enhanced CT. No further improvement in sensitivity was achieved with the combination of both sequences in comparison to that with contrast enhanced CT only."
Suspected Appendicitis in Children: Diagnosis with Contrast-enhanced versus Nonenhanced Helical CT
Kaiser S et al.
Radiology 2004;231:427-433 - "Readers diagnosed appendicitis with 66% spooled sensitivity and 96% pooled specificity with limited area nonenhanced CT. With contrast enhanced CT of the entire abdomen appendicitis was diagnosed with 90% pooled sensitivity and 94% pooled specificity."
Suspected Appendicitis in Children: Diagnosis with Contrast-enhanced versus Nonenhanced Helical CT
Kaiser S et al.
Radiology 2004;231:427-433 - Mesenteric Adenitis: Key Facts
- Benign self limiting inflammation of right sided mesenteric lymph nodes without an identifiable underlying inflammatory process
- More common in children
- Key is to visualize a normal appendix
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