Syringomyelia

Re: Syringomyelia

Gillian Mostyn — Wed, 29 Aug 2012 23:35:46 GMT

[quote user="Mark Lowrie"]You mention that the main (only?) clinical sign is scratching at the neck almost constantly. I tend to think this is due to a ‘pins and needles’ type pain and I always feel this is more due to CM than SM[/quote]

Although I said 'scratching', it is more like a refelx twitching of the back legs. The foot sometimes contacts the thoracic wall but often just waves in mid air! It very rarely comes anywhere near the neck. Both legs are equally used. The dog does it all the time, but gets a lot worse when anxious. The dog has never had any skin issues at all (unusually) and there is no indication that the skin is actually itchy - no panniculus reflex etc. Although we have discussed MRI at length, the owner would rather not (her issues, not mine). The dog had both stifles fixed (luxating patellas) when young and now has cruciate issues so she does have experience of referral. She hasn't had any bad experiences, I think she just doesn't want to go through the process again.

The dog doesn't yelp or seem in pain as such - it's QOL is simply impaired because it spends it's life 'scratching'. The amount of this behaviour didn't change on medication.

I think I'll retry the gabapentin but with the owner aware of the info above.

Thanks to everyone for all your help - it is much appreciated.

Re: Syringomyelia

Malcolm Ness — Wed, 29 Aug 2012 10:26:53 GMT

[quote user="Mark Lowrie"]However, I repeat what I said at the beginning, this is only opinion and may go against what others advise[/quote]

We also see quite a few of these cases and my opinion meshes with Mark's almost perfectly.

The high number of clinically normal/MRI abnormal dogs is a problem - I do wonder how frequently it is the MRI that is being treated and not the dog!

I am a keen surgeon but to date, like Mark, I have managed to avoid operating on one of these dogs.

Re: Syringomyelia

Mark Lowrie — Wed, 29 Aug 2012 09:34:45 GMT

Hi Gillian,

I think there are a few points surrounding this case. However, before I mention them they are predominantly only my opinion and very little is known about the correct treatment for Chiari-like malformation (CM) with syringomyelia (SM). Therefore the points below are based on my perception and experience of managing the disease.

You mention that the main (only?) clinical sign is scratching at the neck almost constantly. I tend to think this is due to a ‘pins and needles’ type pain and I always feel this is more due to CM than SM. The other familiar sign seen in some of these dogs is mild to severe yelping. I tend to consider this more a symptom of severe SM. Based on this, if the scratching is related to this condition I would expect CM to be the predominant finding should an MRI be done. Having said all of this we see little in the way of a relationship between clinical signs and MRI changes, i.e. a severely clinically affected dog may have mild MRI changes and vice versa. This is one of the reasons that little peer-reviewed literature exists on management of the condition. Also, at least 70% of asymptomatic CKCS have CM. Therefore if an MRI is performed in this dog it is at least 70% likely to have CM. This does not mean that CM is causing the problem. Diagnosis should only be made on ruling-out other conditions.

Management of this condition is usually very successful at controlling the yelping pain. I believe that scratching behaviour can be hard to control and frequently it is difficult to eradicate it completely. Therefore before starting treatment it is important to have some index to monitor that informs us as to whether there is a beneficial response or not. What informed you (and/or the owner) that treatment had failed? Did the owner perceive failure simply because the scratching behaviour did not go away completely? The reason I ask is the owner mentions this TV program. I suspect this dog had different clinical signs to their dog (e.g. yelping) which is managed well with medication. Can you be certain the scratching behaviour didn’t diminish at all on medication? Can you be certain the scratching is neurological in cause and that the dog doesn’t have mild atopy/derm disease? If there is no improvement at all in the scratching on medical management I would certainly be worried about a derm problem.

Management for this disease is described as surgical vs medical. Opinion amongst neurologists is divided as to the ‘correct’ or most successful management. I always start with medical management. To date I have yet to see a dog that has not responded well to medical management alone and therefore have not performed the surgery. My experience with surgical management is therefore limited as I reserve it for those that fail medical management.

My first-line medical treatment is gabapentin 10-20 mg/kg BID/TID. In a CKCS this usually equates to 100mg TID but I am happy to go as high as 200mg TID if necessary. I give this for 2 weeks and if all is going well slowly taper to the lowest dose to maintain a remission of clinical signs.

Other posters have mentioned all the combinations that can be trialled. If gabapentin does not work then I will try various NSAIDs, if this fails then frusemide is good (1 mg/kg BID initially). Pred is also very good (0.5 mg/kg BID initially). If these don’t work alone then any combination is worth trying. If you have tried all of these then I would consider a combination of pred, gabapentin and frusemide. If this is not reducing the symptoms of scratching then I really would question if CM/SM is to blame.

However, I repeat what I said at the beginning, this is only opinion and may go against what others advise. I know Clare may disagree with some of the points I’ve made but I can only base my opinion on the population of cases I see and we sadly see a lot of CKCS with CM/SM. Clare may well be seeing more severe cases given her role in investigating the condition.

Re: Syringomyelia

Thomas Johnson — Wed, 29 Aug 2012 08:36:12 GMT

[quote user="Utlendigur"]

I've also heard of frusemide being used, presumably to reduce CSF production, but I don't know how effective it is.

[/quote]

i did once hear someone suggest that frusemide could be used to test for SM. If it gave an improvement in clinical signs when used alone it would support a diagnosis, whereas pain killers and anti-inflammatories would also treat other conditions causing neck pain.

I haven't tried this and would still push for an MRI.

Re: Syringomyelia

Utlendigur — Tue, 28 Aug 2012 23:01:45 GMT

I've also heard of frusemide being used, presumably to reduce CSF production, but I don't know how effective it is.

Re: Syringomyelia

Andrew Kent — Tue, 28 Aug 2012 22:51:20 GMT

[quote user="Gillian Mostyn"]

Would that make a difference if the owner does not want any invasive treatments/surgery?

[/quote] Some of the medical treatments have the potential for significant side effects and none have been tested for more than 12 months so I would say you want to know for sure what you are treating before you swap one problem for another. Equally the tx of SM can be very frustrating and so if your response is poor you won't know if it is because your diagnosis is wrong or you need a different dose/drug.

Re: Syringomyelia

Gillian Mostyn — Tue, 28 Aug 2012 20:40:14 GMT

Would that make a difference if the owner does not want any invasive treatments/surgery?

Re: Syringomyelia

Mark Rowland — Tue, 28 Aug 2012 20:31:54 GMT

Having spoken to CR about the condition today, I would still do the MRI as it is possible that there might just be CM without syringomyelia

Re: Syringomyelia

Mark Norcott — Tue, 28 Aug 2012 17:39:53 GMT

There is complete information on Clare Rusbridge's website (www.veterinary-neurologist.co.uk) which I would highly recommend. There is an excellent treatment algorithm there.

If using gabapentin, the starting dose is typically 10mg/kg bid (I have a dog on 20mg/kg tid).

Re: Syringomyelia

Rajat — Tue, 28 Aug 2012 16:55:22 GMT

Hi Gillian, I'm sure you have tried these but this is what I would use..

Gabapentin (4-8mg/kg bid-tid starting at low end of dose) or Pre gabalin if no response to this

NSAIDs or Preds (0.5mg/kg sid-bid then reduce to lowest effective dose) if no response to NSAIDS

Tramadol 2-5mg/kg bid

Acupuncture