View Full Version : Copy of Daisy's Mri scan.
19th January 2010, 08:40 PM
Copy of Daisy's scan and certificate.
I'd appreciate any comments on the findings.
19th January 2010, 10:27 PM
I thought syrinx showed up white so I'm a little confused.
19th January 2010, 11:05 PM
If those syrinxes(they look largeC2-C4) are that bad, I would have expected more herniation. It is hard to tell looking at one picture.
In other words, I've seen much more crowded heads without those size syrinxes. Interesting.
19th January 2010, 11:25 PM
Well spotted Sandy.
That's the reason I posted the scan.I was surprising to see the syrinxs in the absence of dilation and herniation....but there we have it! Perhaps there's some minor herniation that's not evident.
He asked about possibility of trauma or injury,but She's been a professional lapdog and has never had a serious fall or impact that I can recall.
There was no discussion about CM so I don't know if that's relevant or irrelevant.
19th January 2010, 11:35 PM
To me the cerebellum looks squished at the back but it is hard to see in the scan. Syrinxes show white on some MRIs and black on others -- depends on the machine. The syrinxes are fairly large but look somewhat thin and long which is better than wide and long or wide and short. However the second one seems large enough to cause a slight bulge... What are the cross sections like? Are the syrinxes centered or off centre? Herniation doesn't really correlate to size of syrinx -- this has been stated in a few of the research papers on this. :thmbsup: The opening into the foramen magnum and the dynamics of CSF flow are believed to be equally and in some cases, may be more relevant. I do know it is not unusual to have syrinxes without herniation.
19th January 2010, 11:40 PM
The cross sections are centred Karlin.
19th January 2010, 11:43 PM
This is what I picture in my mind when I think of crowding and herniation.
And actually (to me at least), this dogs head doesn't look positioned correctly
19th January 2010, 11:45 PM
More info here and some comparison images:
You can see how much space there is for a rounded cerebellum on the staffie.
19th January 2010, 11:54 PM
CM is almost ubiquitous in Cavalier King Charles spaniels (CKCS); Cerda-Gonzalez et al (2009) found that 92% had at least one craniocervical morphologic abnormality detected in MR images. However severity of the CM does not predict the presence of syringomyelia although Cavaliers with clinical signs from syringomyelia are more likely to have smaller cauda fossas (i.e. back of skull) volume compared to unaffected Cavaliers (Cerda-Gonzalez et al 2009).
20th January 2010, 12:02 AM
This is a slightly better film.
20th January 2010, 12:11 AM
Wow that is definitely compacted, to my eye. You can see how the rounded shape of the cerebellum is flattened inwards by the back of the skull. Unfortunately Geoff's scans can sometimes be confusing as he uses a different approach to analysis (and I think a lot of UK breeders have confused the issue of the existence (or not) of herniation with the existence of CM and believe they have a totally clear cavalier if he checks that there's no herniation. I know I initially confused the two as I assumed there was a direct correlation between herniation and CM,but there isn't always). He notes herniation -- which many neurologists do not feel is necessarily significant, but not CM. All others note CM. It would be helpful if there were a standard (there will be with the BVA/MRI scheme).
I've PMd you...
20th January 2010, 12:39 AM
Thanks for that Karlin.
That sounds perfectly logical.:).
20th January 2010, 03:03 AM
Just for the record, I was wrong, the syrinx are not meant to be white, my mistake.
20th January 2010, 10:00 PM
Thanks for posting the scan, Sins - always interesting to see other people's! Perhaps the the apparent lack of herniation is related to the lack of dilation of the ventricles, which are still pretty small - Oliver's, for instance, are about four times that size (almost identical to the example on the Rusbridge website). As I understand it, the increased size of the ventricles expands the size of the brain, which has to go somewhere, and if it gets pushed downwards it then gets 'pinched' by the CM, causing the herniation. So the CM both causes the initial problem with the flow of the cerebro-spinal fluid, and when the brain moves downwards causes herniation. So presumably Daisy's CM is slowing down the circulation of the fluid enought to produce the syrinxes (which are much bigger than Oliver's), but the fluid is not backing up in the ventricles enough to produce obvious herniation. Does that make sense? (As far as anything to do with SM ever makes sense!)
Kate, Oliver and Aled
21st January 2010, 10:54 PM
This thread has really opened my eyes. I have never really understood SM before now but with the diagrams it makes it much clearer. Poor little guys. Its heartbreaking!
22nd January 2010, 02:33 AM
I would think perhaps there is some herniation there as well, going by the second image. It might be worth getting a second opinion on the interpretation. The original interpretation may depend on the views examined at the time and also, there can be missed subtleties. I've had two different interpretations on herniation myself with one of my MRIs. :thmbsup: The BVA scheme will be very helpful as interpretations will be done by two specialists, with an agreed baseline way of interpreting. That should be very helpful to breeders.
22nd January 2010, 11:36 AM
I think the way forward Karlin,will be to get her onto a diuretic as GS suggested and maybe get a follow up scan done in 12-18 months.As she's insured,I'll try and get the full diagnostic scan done then at the UCD vet college??I'm very mindful of the fact that what we got done was a screening scan and not a catch all diagnostic scan...so it probably has it's limitations,but the bottom line is that she has syrinxs.
Thanks for all the feedback.
22nd January 2010, 01:50 PM
If you come up here, let me know and if I'm free I'd come meet you. :)
13th March 2010, 06:38 PM
Just to answer the debate about whether a syrinx will be white or black - it depends on the sequence used for the imaging. A T1 scan has fluid dark, and a T2 scan has fluid bright. Therefore, on some scans it will be black if its a T1 and white if its a T2.
Also - you can't tell if there is ventricular dilation from a midline sagittal (the scan that shows the brain and spinal cord). You have to see a transverse thru the ventricles.
Unfortunately on this scan, Daisy does have CM. Her cerebellum hangs at (or slightly below) the foramen magnum.
16th March 2010, 02:08 AM
Thanks for the very helpful explanation, Karen! :) I always wondered why sometimes they are white, sometimes black.
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