The role of spinal tissue scarring in the pathogenesis of progressive post-traumatic myelomalacia

Does long segment subarachnoido-subarachnoid shunt prevent posttraumatic and postinfectious spinal arachnoid cyst recurrence?: technical note and case series

Syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be defined as a rare but progressive disease with potentially devastating clinical consequences. Diagnosis can be challenging due to the absence of specific clinical findings, confusion with other pathologies, and late imaging modalities. The treatment strategy for syringomyelia associated with extensive SAA should include direct drainage of the syringomyelia, and dissection of the adhesive arachnoid with expansive duraplasty. Hence, several approaches have been reported for arachnoid dissection and decompression of the subarachnoid space. The high risk of recurrence after the operation is one of the most challenging situations. First two cases were operated previously, and the cyst walls were removed and anastomosed to the intact subarachnoid space at the upper and lower ends by each other. However, in both cases, the cyst recurred after a short time and they were anastomosed again in our clinic. A subarachnoid-subarachnoid shunt was placed with a multi-hole silicone tube extending to the proximal and distal intact subarachnoid spaces and passing through the cyst removal area. In our third case, the shunt system we described was applied directly, and satisfactory results were obtained in the clinical follow-up of the patient. It has been demonstrated that subarachnoido-subarachnoid shunt is a very satisfactory treatment option for this type of pathology, which is difficult to follow and treat.

High-resolution Micro-CT Myelography to Assess Spinal Subarachnoid Space Changes After Spinal Cord Injury in Rats

BACKGROUND AND PURPOSE

The spinal subarachnoid space (SSAS) is vital for neurologic function. Although SSAS alterations are known to occur after spinal cord injury (SCI), there is a lack of high-resolution imaging studies of the SSAS after SCI in rodents. Therefore, the aim here was to assess changes in the SSAS of rats subjected to graded SCI, using high-resolution micro-CT myelography.

METHODS

Long-Evans adult rats were subjected to mild or severe spinal cord contusion at T9. Imaging studies of SSAS features were carried out in injured rats at acute (day 1) and subacute (day 15) stages postinjury, as well as in control rats, using high-resolution micro-CT myelography with a contrast-enhanced digital subtraction protocol. We studied a total of 33 rats randomly allocated into five experimental groups. Micro-CT myelograms were assessed by expert observers using both qualitative and quantitative criteria.

RESULTS

Qualitative and quantitative analyses showed that SCI induces changes in the SSAS that vary as a function of both injury severity and time elapsed after injury. SSAS blockage was the main alteration detected. Moreover, the method used here allowed fine details to be observed in small animals, such as variations in the preferential pathways for contrast medium flow, neuroimaging nerve root enhancement, and leakage of contrast medium due to tearing of the dural sac.

CONCLUSION

Micro-CT myelography provides high-resolution images of changes in the SSAS after SCI in rats and is a useful tool for further experimental studies involving rat SCI in vivo.

Safety and Efficacy of Syringoperitoneal Shunting with a Programmable Shunt Valve for Syringomyelia Associated with Extensive Spinal Adhesive Arachnoiditis: Technical Note

OBJECTIVE

Although syringomyelia associated with extensive spinal adhesive arachnoiditis (SAA) can be a progressive disease that has potentially devastating clinical consequences, its surgical resolution has remained poorly defined. The aim of the present study was to verify the safety and efficacy of syringoperitoneal shunting for syringomyelia associated with extensive SAA.

METHODS

The present retrospective study included 15 patients who had undergone syringoperitoneal shunting with a programmable shunt valve for the diagnosis of syringomyelia associated with extensive SAA from October 2012 to June 2018. The shunt pressure was appropriately adjusted according to the postoperative sequential clinical condition and change in syringomyelia evaluated using magnetic resonance imaging. The average postoperative follow-up duration was 32.7 months.

RESULTS

No surgery-related complications such as shunt dysfunction or infection occurred during the follow-up period, except for 2 patients with minor issues with the shunt tube. The average shunt pressure at the last follow-up examination was 4.5 cm H₂O. The findings from the clinical assessment suggested that the average grade on the sensory pain scale was 2.9 before surgery and had improved significantly to 2.5 at the most recent follow-up examination. Radiological analysis suggested that improvement of syringomyelia was noted in 14 of the 15 patients (93.3%), with no cases of radiological aggravation. No recurrence of syringomyelia developed during the follow-up period in the present study.

CONCLUSION

Syringoperitoneal shunting with a programmable shunt valve was safe and effective for clinical control of syringomyelia associated with extensive SAA. Long-term follow-up is mandatory to monitor for shunt dysfunction and mechanical trouble.

Symptomatic spinal cord kinking due to focal adhesive arachnoiditis, with ossification of the ligamentum flavum: a case report

STUDY DESIGN

A case report.

OBJECTIVE

To describe a rare case of symptomatic spinal cord kinking due to focal adhesive arachnoiditis, with ossification of the ligamentum flavum (OLF).

SUMMARY OF BACKGROUND DATA

Spinal cord kinking without spinal surgery is rare, and symptomatic spinal cord kinking due to focal adhesive arachnoiditis, with OLF is even rarer.

METHODS

A 66-year-old female presented with numbness of the lower extremities and subsequently experienced gait disturbance due to motor weakness. Magnetic resonance imaging of the thoracic spine showed anterior displacement and kinking of the spinal cord from T11 to T12. Laminectomy and OLF resection were performed. The arachnoid membrane at the affected part was markedly thick and seemed cloudy. Adhesiolysis for arachnoid adhesion and release of spinal kinking were performed.

RESULTS

She could walk with a cane 6 months postoperatively. One year postoperatively, thoracic computed tomography-myelography showed that the cord was repositioned in the dural sac, and that release of the spinal cord kink was maintained.

CONCLUSION

Symptomatic spinal cord kinking due to focal adhesive arachnoiditis, with OLF is a rare clinical condition. It was difficult to diagnose the precise pathology of the spinal cord before surgery. Microsurgical arachnoidolysis resolved the spinal cord kinking, and no recurrence was noted within the follow-up period.

LEVEL OF EVIDENCE

N/A.

Spatial and temporal morphological changes in the subarachnoid space after graded spinal cord contusion in the rat

Spontaneous repair or treatment-induced recovery after spinal cord injury (SCI) is very limited and might be related to extramedullary alterations that have only briefly been documented. Here we report on the morphological changes of the spinal subarachnoid space (SAS) in a clinically relevant model of SCI. Anesthetized rats were subjected either to mild or severe spinal cord contusion at T9. Spine blocks from the site of injury and adjacent segments were harvested at acute (1 h and 1 day [d]), subacute (3 and 7 d), and chronic (1 and 3 months) stages post-injury. Histopathology and morphometry at each decalcified vertebral level were assessed. At acute and subacute stages, reduction of SAS lumen was observed after both mild and severe injuries. Acutely, after severe injuries, SAS occlusion was associated mainly with cord swelling and subarachnoid hematomas; a trend for dural sac constriction was observed for mild injuries. At 7 d, cord swelling diminished in both instances, but dural sac constriction increased for severe injuries. At early stages, in the epicenter and vicinity, histopathology revealed compression of neurovascular elements within the SAS, which was more intense in severe than in mild injuries. In the chronic stage, SAS lumen increased notably, mostly from cord atrophy, despite dural sac constriction. Myelograms complemented observations made on SAS lumen permeability. Post-traumatic arachnoiditis occurred mainly in animals with severe injury. In conclusion, early extramedullary SAS changes described here might be expected to produce alterations in cerebrospinal fluid (CSF) dynamics and cord blood perfusion, thereby contributing to the pathophysiology of SCI and becoming novel targets for treatment.

Perilesional myeloradiculopathy with tethered cord in post-traumatic spinal cord injury

STUDY DESIGN

A retrospective series of cases.

OBJECTIVE

To identify, among post-traumatic myelopathies, a specific entity in which clinical and radiological features are not extensive but are strictly limited to the perilesional zone.

SETTING

The data set of the Regional Spinal Cord Injury Department of Nantes, France.

METHODS

A systematic analysis of all traumatic spinal cord injury (SCI) patients who presented with a neurological aggravation delayed from initial injury, without syringomyelia or extensive myelomalacia.

RESULTS

Twelve patients presenting with this type of complication were identified (that is, four tetraplegics and eight paraplegics). The neurological worsening consisted in weakness of the muscles close to the motor level in five patients, and in isolated at-level neuropathic pain in seven patients. A tethered cord was evidenced by the magnetic resonance imaging (MRI) results in all of the patients. Roots were involved by the tethering on the MRI results in eight cases. Surgery, with untethering and expansile duraplasty, was performed in all cases. Surgery allowed motor recovery in patients who presented with a motor loss (motor score gain range=1-7 points; median=3) and decreased pain in all pain patients (decrease on the 10-point numerical rating scale: range=1-6 points; median=4).

CONCLUSIONS

In traumatic SCI patients, a tethered cord could be responsible for clinical and radiological changes, which are strictly localised to the perilesional area. The term perilesional myeloradiculopathy is proposed for this complication, which requires cord release surgery.

Focal adhesive arachnoiditis of the spinal cord: Imaging diagnosis and surgical resolution

Background:

Although adhesive arachnoiditis of the spinal cord can cause progressive symptoms associated with syringomyelia or myelomalacia, its surgical resolution based on the imaging diagnosis is not well characterized. This study aims to describe the use of imaging for the diagnosis of focal adhesive arachnoiditis of the spinal cord and its surgical resolution using microsurgical arachnoidolysis.

Materials and Methods:

Four consecutive patients with symptomatic syringomyelia or myelomalacia caused by focal adhesive arachnoiditis underwent microsurgical arachnoidolysis. Comprehensive imaging evaluation using constructive interference in steady-state (CISS) magnetic resonance imaging (MRI) or myelographic MR imaging using true fast imaging with steady-state precession (TrueFISP) sequences was included before surgery to determine the surgical indication.

Results:

In all four patients a focal adhesion was identified at the cervical or thoracic level of the spinal cord, a consequence of infection or trauma. Three patients showed modest or minor improvement in neurological function, and one patient was unchanged after surgery. The syringomyelia or myelomalacia resolved after surgery and no recurrence was noted within the follow-up period, which ranged from 5 months to 30 months.

Conclusions:

MRI diagnosis of focal adhesive arachnoiditis is critical to determine the surgical indication. Microsurgical arachnoidolysis appears to be a straightforward method for stabilizing the progressive symptoms, though the procedure is technically demanding.