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I was coming from huge and powerful machines (Control Data Cyber) with zillions of  megas of  hard disk, tons of memory, innumerable users thirsty for CPU time. One day someone comes and shows me a CROMEMCO (my first micro). Surprise! It had an operating system whose name was: Unix, what is that?

I kept it.  Later in time I learned about other things, VMS, VM, AIX, PROTEUS, MS.DOS (and its sequel), UNIX ATT 4.2, etc...

For my spare time I acquired a 386 and installed on it a UNIX ATT 4.2 with X11(R3) and Motif(1.0), but in certain magazines there were already advertisements of a version 5 of X11, Motif 1.2.4 and an operating system (UNIX) that cost 50 US dollars. Well, those of you with working experience in SCO or any other, will know what their licenses cost. I invested 250 US dollars on the purchase of that OS and Motif. It arrived after a month.  It was a Yggdrasyl with kernel 0.95.  I gave it a whole hard disk first, later all the computer, and finally my professional life (and I do not regret it).

Evaluating Linux

This good man has a company (DAPSYS SA.) devoted to healthcare informatics. His specialty was storage and retrieval of radiological images for screen devices, either with X11 or Motif or Win95. After trying Linux for few days (15) he adopted it, sending to the garbage 2 AIX, 1 HP800 and 1 DEC with Ultrix. Today he is a happy man with a "portable" and his Linux.

This company already had a few installations in Switzerland when a great opportunity presented itself in Canada. Almost without warning two salesmen from a large American company showed up. They were not coming to sell something but to check "something" that "someone" mentioned to then at the RSNA in Chicago. The RSNA is the world event in the subject of radiology. Two months later the director of DAPSYS went to Montreal with his "portable" to demonstrate the product to several doctors; three months later (504 years after Colon),  I'm off  to the Americas to perform the first installation in that continent of  Iris. Iris is an application for the archival and retrieval of radiological images.

This first installation clearly showed the robustness of the product, of which Linux is great part, and that we could handle the problem correctly.

St. John

Radiology is a specialty that is usually very expensive both in equipment and in film stock. This last item can take 15 to 20% of the annual budget of any radiological department. For this and other reasons it was desirable to eliminate film usage and substitute it for a computer screen.

Furthermore, Iris allows one to centralize ALL the radiological events by patient. Each image has recorded in it the first and family name and patient code. Iris permits retrieval of  this information through OCR techniques, extracting this data and archiving it together with the existing images of the patient (in case there are any).

Iris not only saves in film expense, but it also saves storage space (Hospitals must archive the images for all its patients for years), images can be shared simultaneously among several physicians kilometers away (even with an ocean in between), and they can be searched very rapidly.

In the anglophone part of Canada there is a tendency to centralize healthcare in phases;  first regionally and then at the provincial level. Each province has a certain independence and the province that hired us for this first installation has seven regions.

In this region we are going to connect six hospitals though a WAN ATM of 100 and 10 Megabit, Linux has nothing to do with this network, it only works on it, but it allows us to stress the importance of its tasks.

The headquarters for the whole system is located at St. John hospital. It has two archives, the first one has the following specs:

• 1 Pentium Pro 200Mhz 
• 112G of Hard Disk 
• 1 DAT robot with 200G in tapes 
• 1 Network card 10Mb 
• 1 Network card 100Mb 

In a first phase the network will consist of six hospitals, with two more being added during the second phase of the project. In the first phase we are going to connect the following: 

• 4 stations X11 with double screen for diagnostics in the hospitals themselves. 
• 12 stations W95 for examinations in various hospitals. 
• 17 stations W95 for doctors outside the hospitals. 

What is Linux doing in a Hospital ? 

In the healthcare environment Linux has an incomparable strength: its price and the type of hardware it uses.

For the same functionality the final cost usually is about 50% or less compared to Sun, HP, IBM or DEC stations and Linux functionality has nothing to envy in the others.

The saving on Linux allows hospitals to install a larger number of stations and more hardware throughout the hospital and it allows them to increment its services, which in Canada are not public but semi-public.  The hospitals are regional and depend on the regional governments, but their budgets are only partly supported by the regional tax-payers.  The other part comes from the services provided to local establishments. Linux, therefore means better and more services for less costs and more income. It also means that hospitals can pass down to smaller clinics and patients the savings and can stay competitive.

With regard to the robustness of Linux , all I have to say is that  I have a server with a record up-time of 26 months. 

Nobody and that means NOBODY, has given us any objections to using Linux for the installation. What really counts is the solution and that the solution WORKS.  This concept is very far from the old idea of setting up an operating system (with a known name) as a solution and then a program that sharpens that solution.

The truth is that we have not had any problems putting Linux into the various hospitals, or suffered any funny comments. On the contrary I have detected a certain respect with regards to the word Linux, but for some reason, this system seems to be most supported in the USA  rather than Canada (although this may appear strange, because Canada is, in a sense, like the USA).

What are those two servers doing?

The topology of the network is very simple, for each hospital:
1) Ethernet of 10Mg/bits for 

• - Radiology Halls 
• - Iris Servers (2) 

• - Iris Servers(2) 
• - Visualization Servers 
• - Router to the WAN of the remaining hospitals and network of medical services. 

In a server

When the images are shot, they arrive directly to the server which has to be capable of "reading" the image and extracting the patient data in order to forward it to the visualization stations and archive them with the other patient data. 

Before archiving an image, it goes through a process of "clean up" and non-destructive compression. We now achieve compression ratios of 60%. We could achieve higher ratios, but it would be at the expense of performance in the archival process and later restoration of the images.

According to the tests performed, an image of 512x512x2 takes 0.3 seconds, on average, to appear on the computer screen from the beginning of the transaction. I speak of averages because a study is not always a single image, this average can be improved both by means of hardware and by improving the method of retrieval.

St.John has 12 halls producing 1,000 images per day, this gives us an idea of the volume the servers must handle. During the test period we were reaching the CPU usage of nearly 2%, with 6 halls sending images.

In a client

• SGI workstations 
• IRIS/Motif workstations 
• IRIS/Win95 workstations 

The workstations IRIS/Motif are, mainly, for visualization work with diagnostics. Since they can pilot up to 4 screens, but for the moment they only have two screens of 20 inches each. The searches of the database can be summarized by:

• - Patient Data 
• - Exam Date, Patient birth date 
• - Modality 
• - Pathology 
• - Keyword 

Conclusion

Lately someone in a magazine has managed to spread the idea that the solution for a problem stops by his favorite OS, but if we are good professionals we must be able to convince people that WE know better than any journalist what works or not.
Have fun with Linux...
Bye
Manu

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