Acute renal colic is probably one of the most excruciatingly painful event a person can endure. [1]. Though this is typical of urinary tract calculi, it’s important to note that non-calculus and non-genitourinary conditions can present in a similar manner. Unenhanced helical CT (CT KUB), originally described by Smith et al [2] in 1995, is one single radiological test that has proven successful in the valuation of patients presenting with renal colic. This technique has been shown to be more accurate compared to abdominal radiography [3,4], ultrasound and has replaced excretory urography in the detection of urinary tract calculi in many situations [5]. Currently CT KUB has become the clear test of choice for imaging patients with suspected renal colic for a variety of reasons including its speed, non utilization of contrast, high accuracy for diagnosis or exclusion of stone and determination of stone burden, size and location; assessment of obstructive effects of the stone; identification of significant alternative and additional diagnoses; utility in guiding appropriate patient management [6, 7&8]. Therefore it has gained widespread acceptance among radiologists, emergency department physicians, and urologists. However because of the associated radiation dose, various protocols have been studied in an attempt to reduce this dose and found to be equally accurate [6, 7, 8 &9]. The purpose of this study is therefore to evaluate the diagnostic performance of a low radiation protocol in the patient population referred to our department, by comparing CT KUB findings and clinical outcome(s).