Study on 'The Use of Non-contrast Helical Computerized Tomogram in Predicting Treatment Outcomes of Upper Ureteric Stone by Extracorporeal Shock Wave Lithotripsy Using the Sonolith 4000+ Lithotripter'

Inclusion Criteria: * Adult patient (\> 18 years old) * With solitary upper ureteric stone (defined as ureter above the sacroiliac joint as seen on plain radiography) diagnosed by NCHCT \*(\* can have stones at the other site but the indexed stone is a solitary stone) * Size 5 to 15 mm in the maximal diameter as measured from plain radiography. * Planned for primary in-situ ESWL Exclusion Criteria: * Patient contraindicated for ESWL - active urosepsis, coagulopathy, pregnant lady etc * Presence of percutaneous nephrostomy or ureteric stent * Suspected distal obstruction