Shipping DICOM data between two or many WAN-connected PACS archives is often a burden on infrastructure resources (bandwidth, switches, routers, etc).  A customer requested we install three separate PACS and have each system write data to the other creating a multi-site mesh-configured archival solution.  While at the surface this makes sense, the resources required to execute this solution are in excess of what is necessary.  An additional challenge on top of this is working with the DICOM c-store communication method which is inherently inefficient over WAN connected archives.  With DICOM, each individual medical image that is archived and stored is individually transmitted from the origin to the destination.  Erroneous TCP data encapsulates each communication compounding the amount of bandwidth needed for each communication to occur.

A solution we are now implementing to intelligently archive the medical imaging data produced during a given day is to package it and distribute it to the remote sites using SFTP at the end of business.  Efficiency is increased by a immeasureable magnitude by transporting a single data stream vs. many thousand streams (each individual image).  Once the package arrives at the destination a script extracts that data, parses it and uses DICOM’s c-store method to submit it to the local archive.  As well, an E-mail is sent to the PACS administrator notifying him/her of the success or failure of the transmission.

sudo /System/Library/CoreServices/RemoteManagement/ARDAgent.app/
Contents/Resources/kickstart -activate -configure -access -on -users
admin -privs -all -restart -agent -menu

This command saved my butt when it came time to install two Xserve’s (headless) as I had no access to a Mini Display Port adapter and Server Assistant “shit the bed.”

It’s worth mentioning you should be ssh’d in as Admin/Administrator.  I speculate this won’t work as root, but I don’t know.

Minicolo.net, a Mac Mini co-location and hosting provider, is giving away 5 free MacMini’s to the first five co-location customers. Check it out at http://www.minicolo.net/.

So, the Unix date command is pretty cool.  We often use it in things like shell scripts which need variables that are based on the date.  This is a great link that helped me avoid using the Unix ‘awk’ command to only specify certain components of the date (Year, Month and Day).

Link

Today I begin a five day installation at Veterans Affairs Palo Alto in Palo Alto, CA. We’re upgrading a Pilot solution we installed in early 2008 to extend medical visualization to departments other than radiology. This new installation includes two redundant Apple Xsan’s with over 35TB of aggregate storage for medical imaging (DICOM) data. The entire solution is fundamentally driven by open source software.

We ran out of storage space this week on one of our production PACS installations.  We were anticipating this, though the method for expanding the available storage was up in the air.  Dell is basically giving away direct-attached storage these days – I picked up a PowerEdge R200 (4GB RAM), a PERC 6/E RAID controller and a PowerVault MD1000 with 15TB for under $6k.  We installed RHEL 5 and threw it behind the same Gig-E switch our PACS lives on.  After installing netatalk (AFP for Linux), we mounted the volume on our PACS using AFP and moved our 2007 DICOM data to it.  The storage upgrade worked flawlessly.  Our current rate of consumption at this specific site is 2TB/year – so we’re set for a while, at least.

** Keep in mind our radiologists rarely pull priors (based on recent metrics) so the performance hit we take by moving data to NAS is acceptable.  We looked at AFP and iSCSI as methods for connecting the storage to the PACS via Gig-E; because the two protocols compare in speed/performance, we went with what we know a little better: AFP.