title: Incidental diagnosis of diseases on un-enhanced helical computed tomography performed for ureteric colic.
abstract: BACKGROUND
  Patients presenting in the emergency room with flank pain suggestive of acute ureteric colic may have alternative underlying conditions mimicking ureteric stones. An early diagnosis and appropriate treatment for other causes of flank pain is important. The majority of centers around the world are increasingly using un-enhanced helical CT (UHCT) for evaluation of ureteric colic. This study was conducted to determine the incidence and spectrum of significant incidental diagnoses established or suggested on UHCT performed for suspected renal/ureteric colic.
  
  
  METHODS
  Urologist and radiologist reviewed 233 consecutive UHCT, performed for suspected renal/ureteral colic along with assessment of the medical records. Radiological diagnoses of clinical entities not suspected otherwise were analyzed. All other relevant radiological, biochemical and serological investigations and per-operative findings were also noted.
  
  
  RESULTS
  Ureteral calculi were identified in 148 examinations (64%), findings of recent passage of calculi in 10 (4%) and no calculus in 75 examinations (32%). Overall the incidental findings (additional or alternative diagnosis) were found in 28 (12%) CT scans. Twenty (71%) of these diagnoses were confirmed by per-operative findings, biopsy, and other radiological and biochemical investigations or on clinical follow up.
  
  
  CONCLUSIONS
  A wide spectrum of significant incidental diagnoses can be identified on UHCT performed for suspected renal/ureteral colic. In the present series of 233 consecutive CT examinations, the incidence of incidental diagnosis was 12%.
authors.affiliation: Section of Urology, Department of Surgery, The Aga Khan University, Karachi. nazim.ahmed@aku.edu
authors.forename: Nazim A
authors.initials: NA
authors.lastname: Ahmad
authors.forename: M Hammad
authors.initials: MH
authors.lastname: Ather
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Rees
mesh_terms: D003085:Colic / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D015897:Comorbidity; D006801:Humans; D015994:Incidence; D007669:Kidney Calculi / Q000000981:diagnostic imaging / Q000453:epidemiology; D007674:Kidney Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology; D012680:Sensitivity and Specificity; D036542:Tomography, Spiral Computed / Q000706:statistics & numerical data*; D014514:Ureteral Calculi / Q000000981:diagnostic imaging / Q000453:epidemiology; D014515:Ureteral Diseases / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D014922:Wisconsin / Q000453:epidemiology