Renal stones is considered one of the most painful urologic disorders. Most renal stones pass out of the body without any intervention by a physician. Stones that cause lasting symptoms or other complications may be treated with multiple different methods of intervention. So what is needed is preoperative knowledge of stone composition while the stone is still in situ.

Non contract computerized tomography (NCCT) is currently the preferred method for investigating suspected renal colic, and may be used to identify stone composition. It helps in the preoperative prediction of urinary stone composition. Stone composition influences the choice of treatment modality, follow up schedule and preventive measures against recurrence. NCCT not only provides information regarding urinary tract abnormalities but also aids in determining the stone location, size, shape, density, and skin to surface distance, and the overall health of the kidney.

 So we conducted this study in the department of diagnostic radiology, Assiut University Hospitals between October 2019 and March 2022 aiming to predict the composition of the urinary stones  

The study enrolled seventy three patients  known urolithiasis (49 male and 24 female), the main complaint was loin pain and hematuria.

We found that different stones types based on chemical analysis had insignificant differences as regard size but density of stone was significantly higher among calcium stones and oxalate with apatite in comparison to uric acid stones and calcium oxalate stones.

          As regard site of the stones, different stones types had insignificant differences as regard sites.

In conclusion we found that computed tomography is valuable tool in evaluation the composition of urological stones. The Hounsfield density is a convenient radiographic method that correlates well with the chemical composition of all stone types with high specificity and accuracy.

So we recommend multiple future studies on large number of patients in multiple centers to confirm this study.