A 51-year-old male, with a medical history of hypertension and diabetes mellitus, was admitted to the local hospital due to intermittent acute exacerbation of myelopathy for 3 months. One year earlier, he had developed gait disturbance and difficulty in balancing. There was no history of trauma. Nine months later, the patient had acute onset of paraparesis after waking up in the morning. He collapsed on the ground and could not stand up for a while. After 30 min, he could raise his legs and walk as baseline. He complained of minimal back pain and denied numbness. Two months before hospitalization, he could not stand up after having dinner in the evening. After 30 min later, his symptoms improved. He had occasionally numbness on his left leg. After this event, he had a limitation on ambulation and was unable to walk more than about 50–100 m without stopping to rest. No bowel or bladder involvement was complained. Three weeks before admission, the patient had the same symptoms and rest for about 30 min then improved. MRI of whole spine was performed and was interpreted of a long segment T2 hyperintense cord lesion extending from the level of T4 to the conus medullaris. Lumbar puncture was performed due to the putative diagnosis of transverse myelitis. Cerebrospinal fluid pressure, cell count, and chemistries were within normal limits. The patient was transferred to Prasat Neurological Institute for definite diagnosis and proper management. The physical examination revealed bilateral lower extremity weakness (muscle strength 4/5) without paresthesia. Hyperreflexia was noted in the lower extremities. Babinski's sign was also positive. By counting vertebrae from whole spine screening, there was a degenerative bulging disc at the level of L4–L5 with spinal canal stenosis and compression of bilateral L5 traversing roots []. MRI of the thoracolumbar spine showed the spinal cord congestion at the level of T4 to the conus medullaris with subtle perimedullary flow voids along ventral and dorsal cord surfaces [Figure and ]. Furthermore, there was a curvilinear intradural flow void on T2-weighted image, identified below the conus medullaris. Contrast-enhanced MRA of the thoracolumbar spine demonstrated an enlarged intradural vessel in the midline location extending from the lower lumbar level to the conus medullaris, probably the vein of the filum terminale [], corresponding with the curvilinear flow void on MRI. Spinal angiography demonstrated SDAVF at the level of L4–L5, probably located on the right L5 nerve root sleeve, which is supplied by the right iliolumbar artery originating from the internal iliac artery with cranial drainage into the dilated vein of the filum terminale. The artery of Adamkiewicz arose from the right T8 intercostal artery. Endovascular treatment with NBCA through the right iliolumbar artery was successfully performed to fill in the arterial feeder and fistulous site but fail to reach the proximal vein []. Postembolization angiography of the internal iliac and iliolumbar arteries revealed complete obliteration of the fistula. The patient had gradually improved and was sent back to the local hospital for further physiotherapy. Four months later, he returned and was readmitted to our institution with gait disturbance with the deterioration of clinical symptoms. Follow-up MRI and MRA of the lumbosacral spine revealed unchanged long segment of spinal cord congestion with the presence of SDAVF at the same level. One week later, the patient underwent decompressive laminectomy with obliteration of the intradural draining vein. The patient had significantly improved until being the ability to walk independently 2 weeks later. Spinal angiography, obtained 2 weeks after surgery, confirmed complete obliteration of the fistula []. MRI of the thoracolumbar spine, obtained 4 months after surgery, confirmed the resolution of spinal cord congestion [].
A 58-year-old woman was referred for neurosurgical evaluation because of a 2-year history of rapid decline in bilateral motor functioning. Ten years earlier, she underwent an L4 and L5 laminectomy for cord detethering at an outside facility but had no meaningful improvement. Since then, she had experienced a gradual deterioration in her ambulation. Magnetic resonance imaging (MRI) demonstrated persistent evidence of cord tethering, with an L4/L5 lipomyelomeningocele extending to the sacral hiatus. Notably, prominent flow voids were also seen within the ventral subarachnoid space, with the most caudal draining vessel extending below the S2 sacral body. She had 3/5 strength in her left leg, 4/5 strength in her right, globally diminished sensation to light touch, and pin prick, as well as some bladder urgency. The patient did endorse some lower back pain but also has a history of chronic lower back pain. A diagnostic spinal angiogram showed evidence of a DAVF with arterial feeders from the bilateral lateral sacral arteries and right internal iliac artery with venous drainage to a dilated perimedullary vein. The patient underwent Onyx embolization of both feeding right and left lateral sacral arteries.\nThree months later, the patient exhibited marked improvement in her leg strength and sensation, improved 4-5/5 strength throughout her lower extremities, improved walking with assistance, and marked improvement in balance. At her 6-month follow-up, however, she reported stagnant functional capacity, with worsening of her left leg function that began after a ground-level fall. Physical examination revealed stable to improved right leg strength with subtle worsening of left leg strength (3-4/5). MRI revealed decreased flow voids compared with those seen on the prior study with no evidence of a new abnormality; however, one month later, evaluation revealed globally decreased lower extremity strength (3/5). Repeat spinal angiogram and lumbar MRI revealed new collateralized supply from the right internal iliac artery and lateral sacral branches. The DAVF now extended into the lipomyelomeningocele with dilated draining veins rostrally and spinal canal involvement.\nThe findings of redeveloping DAVF and the patient's clinical condition prompted us to recommend lipomyelomeningocele exploration/resection, DAVF ligation, and cord detethering. A standard midline approach was utilized, and a grossly abnormal fatty myelomeningocele was circumferentially dissected (). Intradural exploration demonstrated diffuse blood supply tracking through the lipomyelomeningocele with a large draining vein ventral to a tethered filum. The filum was sectioned, and the DAVF was clipped and ligated well into the arterialized vein. The remaining lipomyelomeningocele was mobilized and resected ().\nSix months after surgery, the patient regained full motor function of her proximal lower extremities with 5/5 strength throughout and 5/5 and 4/5 strength in her distal right and left lower extremities, respectively. MRI of the thoracic spine demonstrated marked improvement in the appearance of the spinal DAVF, with the tortuous vessels no longer evident. Follow-up spinal angiogram showed no evidence of residual DAVF or early draining vein ().