Spinal arteriovenous malformations: Is surgery indicated?

Knowledge, attitudes and practices regarding spinal vascular malformations among doctors in China: a cross-sectional study

OBJECTIVE

Knowledge, attitude and practice (KAP) models are essential tools for assessing healthcare professionals' understanding, beliefs and behaviours towards specific health issues. This study aimed to explore the KAP of Chinese doctors in diagnosing and treating spinal vascular malformations (SVM).

DESIGN

A web-based cross-sectional survey.

SETTING

This study was conducted between October and December 2022 through a self-administered questionnaire.

PARTICIPANTS

Participants include full-time doctors who voluntarily participate. Doctors in advanced training, regular training or internships were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

The KAP scores of Chinese doctors in diagnosing and treating SVM measured by the questionnaire.

RESULTS

A total of 517 doctors participated in the study, mostly in Shaanxi, China, working in SVM-relevant departments (n=396) or other departments (n=121). The doctors achieved an average knowledge score of 9.66±1.95 (range: 0-12), attitude score of 22.16±1.71 (range: 6-30) and practice scores of 46.13±5.35 for those in SVM-relevant departments (neurosurgery, orthopaedics and neurology) and 8.50±1.25 for those in other departments, respectively, revealing doctors have adequate knowledge, positive attitude and good practice, and those in SVM-relevant departments showing more adeptness compared with those in other departments. Moreover, multivariate logistic regression analysis showed that knowledge about SVM (OR=1.72, 95% CI 1.11 to 2.65, p=0.015), holding a master's degree (OR=1.85, 95% CI 1.14 to 3.00, p=0.013) and working in orthopaedics (OR=0.34, 95% CI 0.13 to 0.88, p=0.026) were independently associated with good attitude.

CONCLUSION

Chinese doctors showed adequate knowledge, moderate attitudes and good practice regarding SVM. A continuing education programme may improve clinical practitioners' ability to manage SVM.

Conus medullary arteriovenous malformation mimicking intramedullary tumor: a case report

Background

Vascular malformation of the spine accounted for 3–4% of all intradural lesions. Spinal arteriovenous malformation (AVM) is often missed because of overlapping symptoms with other pathology and ambiguous imaging. Here, we report a conus medullary AVM that mimics intramedullary tumours either from clinical findings or MR imaging.

Case presentation

We report a 24-year-old man with left foot monoparesis, paresthesia, and intermittent claudication for the last 3 months. Magnetic resonance imaging revealed a strongly enhanced intramedullary lesion with a hypointense signal on T1-weighted images and a hyperintense signal on T2-weighted images without flow void, suggesting an intramedullary tumour of ependymoma. Left-sided hemilaminectomy was performed, revealing an AVM on conus medullary. Microsurgical resection was performed by subsequently ligating the arterial feeder and draining vein using a temporary clip. Improvement of neurological status without postoperative sequelae was noted.

Conclusions

Because of the similarity in epidemiology, symptoms, clinical progression, and imaging, suspicion of spinal AVM should remain. This case highlights that appropriate and meticulous surgical resection can preserve the patient's neurological function.

The recovery management of patients with operated extrame-dullary spinal arteriovenous fistula, evolution and socio-professional reintegration: case report and review of the litera-ture

Adequate therapeutic intervention performed in the case of extradural spinal AVM and an inten-sive recovery program allow the amelioration of neurological manifestations in a very high percentage. With the ultimate goal of practicing a trade, a good biological recovery is needed for social recovery. The effectiveness of strategies for professional integration and reintegration de-pends largely on the patient’s experiences before the onset of the disease. The paper aims to re-view the treatment, the evolution of patients with extradural spinal AV and the possibilities of socio-professional reintegration. Methods and analysis. A case presentation of a patient diag-nosed with extradural spinal AV fistula is proposed, along with a review of the current literature on the treatment of this pathology, the evolution and the possibilities of vocational recovery. The studies will be analysed and selected in two stages, in the first stage the titles and abstracts, in the second stage, the articles with full text will be analysed, selected and a narrative synthesis of the included studies will be made. Summary case. The 51-year-old urban patient, a profes-sional driving instructor who underwent endovascular and surgical treatment for extradural spinal AV fistula, is hospitalized for a moderate motor deficit, such as paraparesis, back pain, mechanical pain in the knees and gait disorders. The objectives of recovery are represented by neuromotor recovery and socio-professional reintegration. Conclusions. Spinal EAVFs are rare lesions with a low risk of bleeding; the clinical manifestations are determined by the compres-sion of the bone marrow; these being significantly improved after the endovascular and surgical treatment. Studies show a good long-term prognosis, which is determined by the absence of re-currences. An essential role in the integration of patients with disabilities in the socio-professional life is the identification of their deficiencies and their reorientation according to the outstanding abilities, the stimulation of the preserved skills. Keywords: rehabilitation, disc hernia, low back pain, paraplegia

Spinal Vascular Shunts: A Patterned Approach

Spinal vascular shunts, including fistulas and malformations, are rare and complex vascular lesions for which multiple classification schemes have been proposed. The most widely adopted scheme consists of 4 types: type I, dural AVFs; type II, intramedullary glomus AVMs; type III, juvenile/metameric AVMs; and type IV, intradural perimedullary AVFs. MR imaging and angiography techniques permit detailed assessment of spinal arteriovenous shunts, though DSA is the criterion standard for delineating vascular anatomy and treatment planning. Diagnosis is almost exclusively based on imaging, and features often mimic more common pathologies. The radiologist's recognition of spinal vascular shunts may improve outcomes because patients may benefit from early intervention.

Microsurgery Versus Endovascular Treatment - Which Is Adequate for Initial Treatment of Spinal Dural Arteriovenous Fistula: A Case Series

Objective

Considering the adverse natural history of spinal dural arteriovenous fistula (sDAVF), clinical outcomes may be worsened if the initial occlusive trial does not achieve complete fistula occlusion. We aimed to analyze the initial success rate of microsurgery and embolization and confirm the effects of initial treatment success on the clinical outcomes of sDAVF patients. In addition, we investigated the factors associated with initial treatment failure.

Methods

A total of 38 patients treated for sDAVF at a single institution over a 14-year period were retrospectively reviewed. Clinical outcomes according to the initial treatment modality were quantitatively analyzed. Demographic characteristics and angioarchitecture data were evaluated to identify factors associated with initial treatment failure.

Results

In the study population, 34 patients underwent embolization as the initial treatment, and complete occlusion of the fistula was achieved in 13 patients (38%). However, all patients who underwent microsurgery showed complete fistula occlusion. Among patients with initial treatment success, gait and micturition were improved with statistical significance (p < 0.001 each). However, in cases of initial treatment failure, only mild improvements in gait and micturition were observed, which were not statistically significant (p = 0.097 and p = 0.375, respectively). A narrow feeding artery diameter (p = 0.007) and embolization of the artery only (p = 0.002) were identified as factors associated with initial treatment failure.

Conclusion

To achieve symptomatic improvement and prevent neurological deterioration due to recurrence, the initial definite occlusion of the fistula is important. Despite advances in endovascular techniques, microsurgical occlusion is still superior in terms of initial complete obliteration.

Intraoperative Neurophysiologic Monitoring Correlates with Neurologic Outcome After Endovascular and Surgical Treatment of a Cervical Arteriovenous Malformation

BACKGROUND

 The treatment of spinal intramedullary arteriovenous malformations (AVMs) presents the risk of spinal cord ischemia because of the vascular nidus and their feeding arteries involving and supplying the spinal cord parenchyma. The multimodal approach includes endovascular embolization and microsurgical excision, both benefiting from intraoperative neurophysiologic monitoring. We present a case study of a patient who underwent several staged embolizations and open surgery for microsurgical excision.

PATIENT

 A 32-year-old man who presented with a recurrent glomus-type intramedullary AVM in the cervical spinal cord, located at the C5-C6 segment, with progressive neurologic deterioration.

METHODS

 Somatosensory evoked potentials (SEPs) and transcranial motor evoked potentials (MEPs) were performed during three embolizations, a provocative test, and surgery, in addition to D-wave during microsurgical excision.

RESULTS

 Abolished hand MEP and drop in SEP during a provocative test guided the surgeon to embolize from a safer vessel with no acute neurologic deficit after three embolizations. Before surgery, an angiography showed the left posterior spinal artery supplying the AVM. After resecting the vascular nidus from the spinal parenchyma, left-hand MEP decreased in amplitude and later abolished, and SEP decreased. Interestingly, no D-wave or distal MEPs were affected. Weakness in the left hand immediately and 2 weeks postoperatively advocates for metameric spinal cord ischemia with preservation of long spinal cord pathways.

CONCLUSIONS

 Intraoperative neurophysiologic monitoring correlates with neurologic outcome after endovascular and surgical treatment of a cervical AVM. Intraoperative monitoring provides continuous functional information of long and metameric spinal cord pathways, which is critical when deciding on the vessel to be embolized and during microsurgical excision where the surgeon is in less control of the AVM hemodynamic flow.

Estimation of the number of feeding arteries of spinal arteriovenous malformations by using three-dimensional digital subtraction angiography

PURPOSE

Spinal angiography is the gold standard for evaluation or diagnosis of spinal arteriovenous malformations (AVMs). However, some feeding arteries might be overlooked when multiple feeders exist. This study aimed to retrospectively review cases of spinal intra-dural AVMs, which were identified by three-dimensional digital subtraction angiography (3D-DSA), and attempted to estimate the number of feeding arteries.

METHODS

We retrospectively reviewed patients with spinal intra-dural AVMs who underwent 3D-DSA at Hokkaido University Hospital from January 2005 to December 2016. We selected 9 patients in whom we could obtain data of multi-planar reconstruction of 3D-DSA. We measured the computed tomography (CT) values of feeding arteries and draining veins. The CT values represented the averages of maximum CT values of 5 continuous axial slices. The ratio of the CT value of feeders to that of drainers (F/D ratio) was calculated. The correlation between the F/D ratio and the number of feeders was examined with Pearson's correlation coefficient.

RESULTS

The average number of feeders was 2.3 (1-4), and the number of feeders was significantly positively correlated with the F/D ratio (r = 0.855, P = .003).

CONCLUSIONS

We conclude that the number of feeding arteries of spinal intra-dural AVMs can be estimated by using the F/D ratio obtained from 3D-DSA. These slides can be retrieved under Electronic Supplementary Material.

Ruptured Spinal Arteriovenous Malformation: A Rare Cause of Paraplegia in Pregnancy

Background

Ruptured spinal arteriovenous malformation (AVM) is a rare cause of paraplegia in pregnancy, with only a few case reports describing complications from spinal AVMs during pregnancy in the literature.

Case

A 32-year-old woman presented at 37 weeks gestation with back pain and rapidly progressive lower limb neurological symptoms. MRI showed a previously undiagnosed spinal AVM at T8. A healthy girl was delivered by caesarean under general anaesthesia to facilitate further investigation. After spinal angiography, it was concluded the most likely aetiology was acute rupture of an intra- and perimedullary AVM with associated haemorrhage at T8 secondary to venous compression from the enlarged uterus at L5 causing high pressure within the AVM and subsequent rupture. The neurosurgical and interventional radiology teams felt the lesion was not amenable to surgical or endovascular intervention. The patient remained paraplegic with no sign of neurological recovery six months after delivery.

Conclusion

While new onset paraplegia during pregnancy secondary to ruptured spinal AVM is very rare, it is important to discuss these cases to inform future practice. In contrast to previous case reports, our patient did not spontaneously recover after delivery and was not amenable to surgical or endovascular treatment.

A Review of Vascular Abnormalities of the Spine

Patients with spinal vascular lesions present with unique symptoms and have important anatomical and physiologic changes that must be considered prior to treatment. In this mini-review, we provide an overview of normal spinal vascular anatomy and discuss several key spinal vascular lesions. We provide an overview of cavernous malformations, intradural arteriovenous malformations, perimedullary arteriovenous fistulas, and dural arteriovenous fistulas. Important considerations are addressed in terms of pathologic characterization, specific imaging findings, and treatment approaches.