Syringomyelia Rapid Review

[Music] hello and welcome to this video on siren go my ilya which is a condition that affects the spinal cord we're going to look at it from an anatomical perspective considering how we get some of the symptoms affecting the interruption of the pathway so what is siren go Melia well it's a cavity known as the syrinx which forms either in the brainstem or in the spinal cord and it expands out segmental level but also longer to dinelli affecting the normal flow of cerebrospinal fluid normally diagnosed by MRI scans and it can develop slowly it can be congenital but quite often it's acquired either from trauma of the spinal cord or from tumors surgery is the main way in which is treated and often the removal does leave permanent damage let's have a look at the cross-section of a spinal cord we're going to look at the cervical spinal cord here we're going to draw on the grey matter which we can see in the centre and we can see the white matter outside we're going to look at how this formation of a cavity or cyst affects the functioning of the tracts so here we can see our grey matter remember that's where the cell bodies of neurons are the white matter is where tracts would run up and down the spinal cord and we need to bring on here one of the important pathways a sensory pathway called the dorsal column pathway and also the position of the spinothalamic pathway this is going to be important for understanding why we get the symptoms we do with a syrinx formation in the middle we have the central canal that's important but also a key landmark here is the anterior Y Kamisha where the spinothalamic pathways cross and here we also can bring on the position of the corticospinal tract a motor pathway that can sometimes be interrupted so the cavity here is called a syrinx it grows out from the central canal much like you can see coming on screen now and it grows out at segmental level but also longer to Denis so slightly up and down it affecting various segmental levels and that can cause problems with understanding some of the symptoms that we have sometimes so how does it affect the pathways well mostly it affects the sensory pathways we're gonna draw on now the spinothalamic pathway this is the first order neuron coming in you can see its cell body at dorsal root ganglion it synapse is in the gray matter in the dorsal horn and then it crosses over the anterior white Kamisha through the damaged region over to the spinothalamic tract on the opposite side so it deca sites and crosses at segmental level and you can see how the spinothalamic pathway will be interrupted there and so now we can see the pathway ascending to the brain although in this case with the syrinx that wouldn't happen because of the damage we can draw it on from the other side and of course it's exactly the same which is why we are going to get a bilateral loss of pain and temperature and pressure and crew touch yeah with this condition so the key thing here is that it's a bilateral interruption because the syrinx grows out from the central canal and interrupts the crossing of the tracks at the anterior white commission so that's that's really important we lose those modalities associated with the spinothalamic tract and that occurs on both sides now normally that occurs as a cape light distribution over the back and the arms because the cavity is growing longer to dinelli as well as growing out at segmental level so the Cape light distribution and the loss of pain and temperature crew touch and pressure bilaterally is as common often patients will present with burn marks to their fingertips because they can still touch but they don't feel pain and the reason why they can still touch or have discriminatory touch is because one of the other key pathways involved in sensation is not affected and the other pathway that's not affected here because of the anatomy is the dorsal column medial lemonis school pathway so let's now take a look at why the dorsal column medial meniscal pathway is not affected here it comes in on each side and you can see it doesn't sign-ups a segmental level and it ascends in the white matter in the dorsal columns Epsilon and therefore it does not have to cross through the damaged region which is where the syrinx is growing out from the central canal so because it does not cross it does not cross the damaged region it ascends healthily on the ipsilateral side and therefore all of the modalities carried with the dorsal column medially meniscal pathway are preserved so this is called dissociated sensory loss where we have the loss of the spinothalamic pathway but we have preservation of the dorsal column pathway it's also worth mentioning here that often the motor pathways can be affected I mentioned before the corticospinal tract sometimes the sinks can grow asymmetrically out and affect the cell bodies of the lower motor neurons leaving the spinal cord causing motor problems and weakness subscribe to Soton brain hub for more 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Channel: Soton Brain Hub

Views: 80,872

Keywords: syringomyelia, dissociated sensory loss, sensory loss, syrinx, spinal cord, csf, sensory pathways, soton brain hub

Id: KLH-3SzsPYM

Length: 5min 33sec (333 seconds)

Published: Sun Apr 01 2018