Slides
Transcript
Well, thank you for the invitation. It’s quite an honor to be able to speak after Marcus before Jürgen. It’s quite a challenge too, but I will do my best. I was asked to talk about idiopathic spinal cord herniation with or without SIH. I will do my best.
I have nothing to disclose besides a taste for very loud music.
I will start with some cases. The first case is a male of 59 years with an antifosfolipid syndrome, otherwise healthy, and he had slowly evolving complaints in two years. They were mostly sensory disturbances of the left leg and the lower abdomen. He had trouble discriminating warm and cold when taking showers, and he had some pain inside the left leg and painful sensations on the left side of the trunk about 10 cm below the nipples. And he also noticed mild difficulty in walking and some stiffness of his legs when he got out of bed in the morning.
On examination, he had diminished sensation for touch and pain in the left leg and the trunk up to T10. He had inability to discriminate warm and cold in the left leg. He had no right-sided sensory disturbances, and gnostic sensation was intact. He had some subtle pyramidal signs, otherwise normal. So we had basically a Brown-Séquard syndrome-like neurological examination.
An MRI was made, and that clearly showed a displaced spinal cord at T6-7 , but that’s actually the apex of the kyfosis also. But an axial MRI showed clear anterior spinal cord herniation.
So I operated under general anesthesia and monitoring. We did a targeted laminectomy. I opened the dura, mobilized the cord, reduced the herniated spinal cord from the defect, and I closed the dural defect with muscle and fibrin glue. I tried to do other things, but that did not work well with the monitoring, and the dura is diminished. So I tried to do this, and it worked quite well. He improved a little, but he was still troubled with the persisting painful zone on the left side of the trunk. But the postoperative MRI looked nice with no herniation anymore and just a small focus of myelopathy.
Anterior spinal cord herniation is actually herniating spinal cord through an anterior dural defect, and it leads to strangulation and tethering of the spinal cord. It’s almost exclusively seen in the thoracic spine, although I was able to find the report of dorsal spinal cord herniation. It is the thoracic spine because of the kyfosis and the ventral position of the cord there. Most people are between 30 and 70, and there’s some slight female preponderance. Clinical presentation is mostly Brown-Séquard syndrome-like myelopathy or other lower extremity motor sensory defects, and rarely SIH.
Actually it was first described in the 70s as an accidental finding during intradural thoracic disc surgery, which was at that time common. It’s a rare condition. It used to be difficult to diagnose, but not anymore with all the MRI possibilities we have now. But it’s important to diagnose because surgical intervention is often useful.
Differential diagnosis is mostly posterior intradural arachnoid webs or cysts, and they often have that typical scalpel sign. As already said, it is mostly seen around the apex of the thoracic kyfosis because of the proximity of the cord to the ventral dura. There’s a lot to do about what is the cause of the ventral dural defect. It might be congenital, like a dural duplicature, or maybe developmental in the sense that the sections of the two blades of the dura exist. It can be after surgery or trauma, but probably most common is degenerative disc changes, spurs, causing slit-like defects in the dura, which can then cause cord herniation but could also be causing ventral CSF leakage and causing SIH.
Well, since spontaneous intracranial hypotension is the topic of this conference, I think we can skip this slide. Everybody will be aware of what the symptoms are.
I’ve been looking for a patient with both SIH and a spinal cord herniation, and Mathijs Brouwer was so kind to come up with this patient. It was actually a patient of his and Peter Vandertop. That patient was seen in Amsterdam, was referred from another hospital. He had some unexplained myelopathic syndrome, probably some kind of mild form of bibrachial atrophy, and there was evidence of anterior epidural fluid collections. He had a history of more than seven years of awkward sensations in his arms, not painful, maybe related to sports. He had, in the past, an MRI of the cervical spine. He had a small disc protrusion which was managed conservatively. He started to develop weakness of his arms later on, and that was stable for some years. Then he also developed decreased sensory sense in the left leg, especially warm-cold discrimination was difficult, and he got some hyperpathic sensations in the left leg. No walking difficulties or other complaints. It didn’t really interfere with his life.
On examination, he was right-handed, had normal cranial nerves, had some right-sided atrophy of the deltoid and the biceps, and also of the right quadriceps, and right-sided weakness, although he complained also about weakness of the left upper arm. He had maybe some pyramidal signs, in the sense that he had normal reflexes in his arms with brisk reflexes in the legs. Otherwise, he had no abnormalities besides some diminished sensory sense of the left leg. He also had this anterior displaced spinal cord and a herniation, but also anterior epidural fluid collections over a large trajectory.
He was operated by Peter Vandertop under general anesthesia monitoring, also targeted posterior approach, cleavage and the resection of the indurated and adherent epidural fat. Opening the dura and mobilizing and rotating the cord, the dural defect was identified. The cord reduced, and he closed the dura with 8-0 sutures and Tachosil.
Here are some pictures to show you. This is the indurated and sticky epidural fat that he encountered firstly. This is the anterior tear on the right side with the rim from the lateral side. This is the caudal end of the tear – it was quite a large tear. The denticulate ligament was tented with sutures, and then the dura, the entire dura, was closed with 8-0 Prolene sutures.
He also improved a little. He had some better power in the leg, otherwise no changes, and the post-op MRI also was nice with resolution of the herniation and of the SLECs.
Well, intracranial hypotension and spinal cord herniation have a common cause. It’s a ventral dural defect in the thoracic spine. However, it’s rarely seen together at debut, maybe because both of them are of course rare. It is mentioned in the literature that it can debut together, but I was not able to find a lot of case reports about that. Probably because the spinal cord herniation tamponades the defect, and also because the insidious onset of the spinal cord herniation symptoms which will probably precede and resolve again before the signs and symptoms of spinal cord herniation are noted.
Therefore, both are rare entities and related, of course, by nature of the underlying pathology – which is an anterior dura defect. The combination of both at the same time at presentation is very rare, but maybe improved awareness and even better imaging techniques will lead to more cases in the future.
Surgery can often halt deterioration and improve outcome. A correct localizing diagnosis is, of course, important. The dural defect can be closed primarily with stitches, but also with patches or slings that you can put under the spinal cord over the defect. You can also obliterate the defect with dural substitute, muscle, or fats. The seal and TachoSil work pretty well also, or combinations of these.
Complications are, apart from the usual complications of this type of surgery, recurrence and especially severe arachnopathy and tethering after a recurrence.
Then I have another peculiar case of spinal herniation and intracranial hypertension syndrome that we encountered in Utrecht two weeks ago. It was a 25-year-old recovery nurse in our own hospital with Loeys-Dietz syndrome, which has been talked about already by Marcus. She went to the doctor because of abdominal complaints, ended up at the gynecology department, and they thought she had an ovarian cyst. There was a laparoscopic fenestration and biopsy of that cyst. Then she was sent home, and she was admitted a few days later with severe positional headache, muffled hearing, dizziness, and nausea. She was seen at the neurology department, where the diagnosis of spontaneous intracranial hypotension was made. Then, of course, we did spinal imaging, and what we actually saw was extensive dural ectasia, but also herniating intestine into the spinal canal at the sacrum. This is a CT scan we made of the sacrum. And you see these very, very strongly enlarged holes of the sacral anterior foramina.
The ovarian cyst that was fenestrated was actually a large cystic herniation of a dural ectasia to the right S2 foramen. We operated her last week, did laparotomy, removed the herniated intestine from the sacrum, and then covered the S2 foramen with artificial dura, TachoSil, fibrin glue, and with a pedicled vertical rectus abdominis muscle flap. She’s doing fine, but she’s still having bed rest because we are very anxious to mobilize her and hope that this will help.
Thank you.