Editing Stones: Evaluation and Medical Management (section)

=== CT scan (without contrast) ===
* '''Findings'''
**'''Pure uric acid stones have much lower Hounsfield units than calcium types'''
**'''Forniceal extravasation'''
*** Usually associated with a small distal ureteral calculus.
*** '''Should be similarly to other ureteral stones:''' intervention should be undertaken when there is an associated fever, nausea/vomiting, or unrelenting pain. Otherwise, conservative observation is appropriate.
*Test characteristics[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5443345/ §]
**Sensitivity: 95%
**Specificity: 98%
*'''Advantages'''
**'''Most sensitive modality for stones'''
*Disadvantages
**Exposure to radiation[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5443345/ §]
***Low-dose CT is ≈3.0 mSv, standard CT without contrast is 10.0 mSV
**Availability
**Cost (10x cost of KUB)[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5443345/ §]