Calculating your PACS storage capacity

I came through a nice table in a presentation from SIIM (society of Imaging Informatics in Medicine) which was showing typical image size and typical full study size for different digital images of different modalities in Radiology. See Table above.
This table will help in estimating the needed PACS storage. From your calculation of No. of exams/day, you can estimate the amount of storage you consume daily and then multiply this by the typical size of each study you will then get the your daily storage consumption (just like the calculation of film consumption in the old days.)
For example, if your department makes 15 CT SCAN cases a day, and by assuming that your study makes 1000 slices per study then each study will comsume around 1GB (assuming your CT is a new one with 1024x1024 image matrix).

Thus, 15 CT cases = 15 GB (per day)
15 GB/day = 15 x (30 working days) = 450 GB / Month
450 GB/Month = 450 x 12 (months a year) = 5400 GB = 5.27 TB

Thus, CT SCAN machine doing 15 cases/day will need a storage of ~ 5 27 TB/year.


Note. PACS admin should anticipate the department growth when using this calculation to estimate the PACS storage needed.