Arrested progression of the cauda equina syndrome of ankylosing spondylitis after lumboperitoneal shunting

Dural Ectasia in Neurofibromatosis 1: Case Series, Management, and Review

BACKGROUND

The natural history and management of dural ectasia in Neurofibromatosis 1 (NF1) is still largely unknown. Dural ectasias are one of the common clinical manifestations of NF1; however, the treatment options for dural ectasias remain unstudied.

OBJECTIVE

To investigate the natural history, diagnosis, management, and outcome of the largest case series of patients with NF1-associated dural ectasia to date.

METHODS

Records from our NF1 clinic were reviewed to identify NF1 patients with computed tomography or magnetic resonance imaging evidence of dural ectasia(s) to determine their clinical course. Demographics, symptoms, radiographic and histopathologic findings, treatment, and clinical course were assessed.

RESULTS

Thirty-four of 37 patients were managed without surgery. Of the 18 initially asymptomatic patients, 5 (27.8%) progressed to symptoms attributable to a dural ectasia (onset of 2.7% per patient-year). Three patients required surgical intervention because of extraspinal mass effect. All 3 initially improved but had symptom recurrence within 2 yr. Reoperation involved shunt placement for cerebrospinal fluid (CSF) diversion. On imaging review, 26 (76.5%) of the nonsurgical patients harbored an associated nearby plexiform neurofibroma. Pathology of one surgical case revealed dural infiltration by diffuse neurofibroma.

CONCLUSION

Using the largest NF1-associated dural ectasia group to date, we report the first symptom-onset rate for nonsurgical patients. In the few cases requiring surgery for decompression, primary resection, and patching of ectasias failed, subsequently requiring CSF shunting. We demonstrate imaging evidence of nearby plexiform neurofibroma in a majority of cases, which, when combined with histopathology, provides a novel explanation for the formation of dural ectasias.

Bulbocavernosus reflex and pudendal nerve somatosensory evoked potential are valuable for the diagnosis of cauda equina syndrome in male patients

AIMS

This study is to assess the value of bulbocavernosus reflex (BCR) and pudendal nerve somatosensory evoked potential (SSEP) in the topical diagnosis of cauda equina syndrome (CES) with or without sphincter dysfunction in male patients.

METHODS

In this study, 40 healthy male adults (control group) and 53 male adult patients (experimental group) were included. The experimental group was subdivided into sphincter subgroup (24 patients with sphincter dysfunction) and non-sphincter subgroup (29 patients without sphincter dysfunction). All subjects underwent BCR and SSEP examinations. The mean latencies of BCR and SSEP P41 were calculated and compared between the control group and the experimental group. Latencies above the average value of +2.58S were considered abnormal. The abnormality rates of BCRs and SSEPs in sphincter and non-sphincter subgroups were calculated, respectively.

RESULTS

BCR and SSEP latencies in the experimental group were remarkably prolonged than those in the control group. BCR and SSEP latencies in sphincter subgroup were remarkably prolonged than those in non-sphincter subgroup. Among the 106 nerves in the experimental group, 87 nerves had prolonged BCR latencies and 3 nerves had no wave elicited, with an abnormality rate of 84.9%. The abnormality rates of BCR were 95.8% and 74.1% in sphincter subgroup and non-sphincter subgroup, respectively. Among the 53 nerves in the experimental group, 39 nerves had prolonged SSEP P41 latencies and 2 nerves had no wave elicited, with an abnormality rate of 77.4%. The abnormality rates of SSEP P41 were 91.7% and 65.5% in sphincter subgroup and non-sphincter subgroup, respectively.

CONCLUSIONS

Both BCR and SSEP were changed in CES patients with or without sphincter dysfunction, and they were especially changed in patients with sphincter dysfunction. BCR and SSEP are valuable in the diagnosis of cauda equina lesions and their severity in males.

Cauda equina syndrome associated with dural ectasia in chronic anlylosing spondylitis

Cauda equina syndrome (CES) associated with dural ectasia is a rare neurologic complication in patients with longstanding ankylosing spondylitis (AS). We report a 68-year-old male with a 30-year history of AS who presented a typical symptom and signs of progressive CES, urinary incontinence and neuropathic pain of the lumbosacral radiculopathy. Computed tomography (CT) and magnetic resonance imaging (MRI) findings showed the unique appearances of dural ectasia, multiple dural diverticula, erosion of posterior element of the lumbar spine, tethering of the conus medullaris and adhesion of the lumbosacral nerve roots to the posterior aspect of the dural ectasia. Considering the progressive worsening of the clinical signs, detethering of the conus medullaris through resection of the filum terminale was performed through a limited laminectomy. However, the urinary incontinence did not improve and there was a partial relief of the neuropathic leg pain only. The possible pathogenetic mechanism of CES-AS and the dural ectasia in this patient with longstanding AS are discussed with a literature review.

Cauda equina syndrome associated with longstanding instrumented spinal fusion

BACKGROUND

This study sought to describe a patient with a slowly progressive cauda equina syndrome (CES) who had imaging findings of the CES that occurs as a rare complication of ankylosing spondylitis (AS), but whose spinal fusion was due to thoracolumbosacral instrumentation, not spondyloarthropathy.

METHODS

A 53-year-old woman presented with a 5-year history of slowly progressive CES affecting sensory and sphincter more than motor function many years after sequential instrumented fusions of her thoracic and then lumbosacral spine. Imaging studies showed enlargement of the caudal sac and dorsal arachnoid diverticula eroding into posterior elements of the lumbar spine similar to findings reported in patients with CES in longstanding AS. Despite extensive evaluation, no other cause for her CES was found. We postulate that our patient's CES is on the same pathophysiologic basis as that proposed for patients with longstanding AS (fibrosis of peridural tissues with increase in transmitted cerebrospinal fluid pulse pressure). Because of reports that patients with CES due to longstanding AS are helped by placement of a lumboperitoneal shunt, our patient underwent this procedure.

RESULTS

Seventeen months postoperatively, the patient's symptoms and neurologic examination are unchanged, and her previous slow progression has been halted.

CONCLUSIONS

This case strongly suggests that extensive surgical thoracolumbosacral fusion can, rarely and after many years, be associated with lumbosacral nerve root damage and a slowly progressive CES that is similar to that seen in patients with spinal fusion due to longstanding AS.

Cauda equina syndrome and dural ectasia: rare manifestations in chronic ankylosing spondylitis

Cauda equina syndrome (CES) is a rare manifestation in patients with long-standing ankylosing spondylitis (AS). We report a 57-year-old male patient with a 30-year history of AS who developed CES in the past 4 years. The CT and MRI examinations showed unique appearances of dural ectasia, multiple dorsal dural diverticula, erosion of the vertebral posterior elements, tethering of the conus medullaris to the dorsal aspect of the spinal canal and adhesion of the nerve roots of the cauda equina to the wall of the dural sac. A large dural defect was found at surgery. De-adhesion of the tethered conus medullaris was performed but without significant clinical improvement. The possible aetiologies of CES and dural ectasia in patients with chronic AS are discussed and the literature is reviewed.

Cauda equina syndrome in ankylosing spondylitis: successful treatment with lumboperitoneal shunting

STUDY DESIGN

Retrospective study.

OBJECTIVE

To assess outcomes after lumboperitoneal shunting for CES with dural sac dilation and multiple arachnoid diverticula in patients with long-standing AS.

SUMMARY OF BACKGROUND DATA

Cauda equina syndrome (CES) is a rare complication of long-standing ankylosing spondylitis (AS). Neurologic symptoms occur insidiously and have a poor prognosis without effective treatment.

METHODS

We retrospectively studied cases seen between 1997 and 2009 at our university-hospital rheumatology department.

RESULTS

We identified 9 patients with AS and dural sac dilation (mean age: 64, range: 38-75), of whom 8 experienced CES 29.1 years on average (range: 10-51) after AS onset. Presenting symptoms were urinary abnormalities (n = 4), sensory abnormalities (n = 6), or radicular or low back pain (n = 4). The symptoms worsened progressively, with mild (n = 3) to severe (n = 1) motor deficiency, sphincter dysfunction (urinary [n = 6] and/or anal [n = 4] sphincter), and impotence (n = 3). Magnetic resonance imaging showed dural sac dilation (n = 9), multiple lumbar arachnoid diverticula (n = 6), erosions of the laminae and spinous processes (n = 6), and nerve-root tethering (n = 6) with adhesion to the dura mater and vertebrae (n = 7). Cerebrospinal fluid (CSF) flow study by magnetic resonance imaging was performed in 2 patients and showed communication of the diverticula with the CSF. Lumboperitoneal shunting, performed in 5 patients, was followed by improvements in sensation (n = 4), urinary symptoms (n = 2), anal continence (n = 3), and pain. Full recovery of muscle strength was noted in 3 patients. Improvements persisted after a mean of 49 months (range: 18-96).

CONCLUSION

Lumboperitoneal shunting induced substantial improvements in all 5 patients treated with this procedure. This result suggests that AS-related CES may be due to chronic arachnoiditis and dural fibrosis leading to diminished CSF resorption with dural sac dilation and diverticula formation.

Combination of transverse myelitis and arachnoiditis in cauda equina syndrome of long-standing ankylosing spondylitis: MRI features and its role in clinical management

The cauda equina syndrome (CES) is a rare neurological complication of ankylosing spondylitis (AS). Imaging diagnosis of CES in long-standing AS patients (CES-AS) using myelography, computed tomography (CT), and magnetic resonance imaging (MRI) were reported in the literature. They, however, demonstrate only the chronic abnormalities of CES-AS, i.e., dural ectasia, dorsal dural diverticula, and selective bone erosion at the posterior elements of the vertebrae. To our knowledge, imaging features of acute intradural inflammation in CES-AS were not described. We report a patient of CES-AS in whom MRI disclosed acute transverse myelitis and arachnoiditis along the lower spinal cord, and discuss the pathogenesis of CES-AS and the role of MRI in clinical management.

Cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome): meta-analysis of outcomes after medical and surgical treatments

The cauda equina syndrome in ankylosing spondylitis (the CES-AS syndrome) is marked by slow, insidious progression and a high incidence of dural ectasia in the lumbosacral spine. A high index of suspicion for this problem must be maintained when evaluating the patient with ankylosing spondylitis with a history of incontinence and neurologic deficit on examination. There has been disagreement in the literature as to whether surgical treatment is warranted for this condition. A meta-analysis was thus performed comparing outcomes with treatment regimens. Our results suggest that leaving these patients untreated or treating with steroids alone is inappropriate. Nonsteroidal antiinflammatory drugs may improve back pain but do not improve neurologic deficit. Surgical treatment of the dural ectasia, either by lumboperitoneal shunting or laminectomy, may improve neurologic dysfunction or halt the progression of neurologic deficit.