Rare Case of Spinal Dural Arteriovenous Fistula with Radiculopathy, without Myelopathy or Spinal Edema on Magnetic Resonance Imaging

Spinal epidural arteriovenous fistula with nerve root enhancement mimicking myeloradiculitis: a case report

BACKGROUND

Gadolinium enhancement of spinal nerve roots on magnetic resonance imaging (MRI) has rarely been reported in spinal dural arteriovenous fistula (SDAVF). Nerve root enhancement and cerebrospinal fluid (CSF) pleocytosis can be deceptive and lead to a misdiagnosis of myeloradiculitis. We report a patient who was initially diagnosed with neurosarcoid myeloradiculitis due to spinal nerve root enhancement, mildly inflammatory cerebrospinal fluid, and pulmonary granulomas, who ultimately was found to have an extensive symptomatic SDAVF.

CASE PRESENTATION

A 52-year-old woman presented with a longitudinally extensive spinal cord lesion with associated gadolinium enhancement of the cord and cauda equina nerve roots, and mild lymphocytic pleocytosis. Pulmonary lymph node biopsy revealed non-caseating granulomas and neurosarcoid myeloradiculitis was suspected. She had rapid and profound clinical deterioration after a single dose of steroids. Further work-up with spinal angiography revealed a thoracic SDAVF, which was surgically ligated leading to clinical improvement.

CONCLUSIONS

This case highlights an unexpected presentation of SDAVF with nerve root enhancement and concurrent pulmonary non-caseating granulomas, leading to an initial misdiagnosis with neurosarcoidosis. Nerve root enhancement has only rarely been described in cases of SDAVF; however, as this case highlights, it is an important consideration in the differential diagnosis of non-inflammatory causes of longitudinally extensive myeloradiculopathy with nerve root enhancement. This point is highly salient due to the importance of avoiding misdiagnosis of SDAVF, as interventions such as steroids or epidural injections used to treat inflammatory or infiltrative mimics may worsen symptoms in SDAVF. We review the presentation, diagnosis, and management of SDAVF as well as a proposed diagnostic approach to differentiating SDAVF from inflammatory myeloradiculitis.

Spinal dural arteriovenous fistula: A rare but treatable disease that should not be missed by orthopedic surgeons

Objective

Spinal dural arteriovenous fistula (SDAVF) is a rare disease that is often misdiagnosed by orthopedic surgeons. We analyzed the reasons for the misdiagnosis and proposed countermeasures.

Methods

Twenty-two SDAVF patients who were initially treated in orthopedics were included. The patients were divided into a correct diagnosis group (A) and a misdiagnosis group (B). The clinical data and prognosis were evaluated.

Results

There were 10 patients in group A and 12 patients in group B. The clinical manifestations included limb numbness, weakness, and bladder and bowel dysfunction. Among these patients without spinal degenerative diseases which had typical magnetic resonance imaging (MRI) features in Group A were more than Group B (P < 0.05). More patients had spinal degenerative diseases in group B. In group A, seven patients were primarily diagnosed with a SDAVF after multidisciplinary teamwork (MDT). In group B, five patients were misdiagnosed with lumbar spinal stenosis, four with lumbar disc herniation, two with thoracic spinal stenosis, and one with cervical spinal stenosis and lumbar spinal stenosis and underwent cervical spinal canal and lumbar spinal canal decompression. The length of time for confirming the diagnosis was 7 months longer in group B than in group A. All patients underwent microsurgery treatment. The average follow-up duration was 11 months. The modified Aminoff-Logue Disability Scale scores showed a statistically significant difference in improvement between the two groups (P < 0.05).

Conclusion

when patients with dysuria especially, have intermittent spinal nerve dysfunction, the possibility of SDAVF should be considered. Awareness of the specific clinical and spinal cord edema and flow voids on MRI of a SDAVF needs to be promoted for orthopedic surgeons. Timely MDT is an important measure for reducing misdiagnosis, and steroids or inappropriate surgery should be avoided until a SDAVF is completely excluded.

Spinal Dural Arteriovenous Fistula: A Mimic of Demyelinating Disease and Radiculopathy

Spinal dural arteriovenous fistula (SDAVF) is characterized by an abnormal connection between a radicular artery and the venous plexus producing spinal cord venous congestion. It manifests with nonspecific sensory and motor symptoms. We present three cases of SDAVF with different forms of presentation; in two cases, an autoimmune etiology was considered, and in the third case, the initial diagnosis was chronic radiculopathy. In all three cases, a serpentine enhancement was observed after the gadolinium in the dorsal region of the spinal cord corresponded to flow voids in T2-weighted images, which guided the diagnosis. SDAVF should be considered in atypical clinical presentations of radiculopathies or spinal cord syndromes, especially spinal conus or epicone syndrome. Likewise, it should be part of the differential diagnosis of spinal cord presentations of demyelinating diseases such as multiple sclerosis or neuromyelitis optica spectrum disorders.

Could gas-filled pseudocyst mimick extruded disc herniation?

There are case reports and small case series in the literature reporting gas-filled pseudocysts (GFP). However, a systematic review presenting overall view of the disease and its management is still lacking. In the present study, we aimed to make a systematic review of GFP cases, and present an exemplary case of ours. Our second aim was to discuss current theories for pathogenesis of GFP. A systematic review of GFP was conducted using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guideline. Two large-scaled data search engines were used. A total of 53 articles were retrieved from the literature and presented with an exemplary case of ours. Mean age of the historical cohort was 59.47 years. There were 66 male (54.1%) and 56 female (45.9%) patients. The most prevalent clinical presentation was radicular sign/symptom in lower limbs with (29.1%) or without low back pain (LBP) (67%). Gas-filled pseudocyst has most commonly been diagnosed at the lower lumbar spine (L4-L5, 45.3%; L5-S1, 37.7%). Surgery was the treatment of choice in most of the patients (80%). In the whole cohort, 79.1% of the patients had complete recovery. Gas-filled pseudocysts are rarely observed in daily practice. They present mostly in men at the age of 60s. Precise differential diagnosis determination using appropriate imaging would help clinicians treat the patients properly. Gas-filled pseudocysts should be treated similarly to other spinal pathologies causing nerve root compression.