Contributed by Kerry Brega1, Lars Widdel1, B. K. Kleinschmidt-DeMasters1,2,3
1Departments of Neurosurgery, 2Pathology and 3Neurology, University of Colorado Health Sciences Center, Denver, CO
CLINICAL HISTORY AND NEUROIMAGING:
A 67 year old male, who had no significant past medical history, presented with a four year history of progressive paraparesis, lower extremity sensory loss, and dysesthesias. He was initially diagnosed and treated for peripheral neuropathy, but his symptoms progressed. Further work-up revealed degenerative changes in his lumbar spine and he underwent a laminectomy at L4-5 for significant stenosis. Unfortunately this surgical procedure also did not alleviate his symptoms. He eventually progressed to complete paraplegia with an associated sensory level at T11 and loss of sphincter control. Other findings on physical examination included significant muscular atrophy and spasticity, with positive clonus and Babinski sign in his lower extremities but sparing of his upper extremities. He otherwise had no other neurological or constitutional symptoms or signs.
Cerebrospinal fluid studies for bacterial, viral, fungal infections, sarcoidosis, demyelinating diseases and neoplastic processes were negative. T1-weighted MRI scan, with gadolinium, revealed a serpiginous, inhomogeneously-enhancing, intramedullary lesion extending from the conus medullaris to the T9 level (Figure 1). Selective intercostal and lumbar artery angiogram did not reveal any spinal vascular malformations, dural arteriovenous malformation, or atypical vascularity. A diagnostic thoraco-lumbar laminectomy and spinal cord biopsy was performed. The spinal cord appeared atrophic with yellowish-white surface discoloration. No arteriovenous malformation could be identified along the exposed spinal cord, either superficially in the leptomeninges, in the adjacent dura, or within the deeper parenchyma of the cord itself.
Small biopsies revealed remote cavitation of cord parenchyma, with the old areas of infarct containing only scattered residual macrophages and innumerable thickened hyalinized small vessels (Figure 2). The surface of the spinal cord manifested severely fibrotic leptomeninges, surface vessels and small parenchymal vessels, which were highlighted by Masson trichrome stain (Figure 3). Numerous small vascular "collagen tubes" were seen within the areas of cord necrosis (Figure 4). Vessels were so thickened that they were not recognizable as arteries or veins and were negative for amyloid on Congo red stain. Small vessels lacked the close juxtaposition of true cavernous angioma. A few non-neoplastic mononuclear cells were seen in the area of the remote infarction and focally within leptomeningeal vessel walls (Figure 5), but no fibrinoid vascular necrosis was apparent. Dilated, telangiectatic vessels throughout the cord suggested alteration in spinal cord vascular circulation even in areas without the severely hyalinized vasculature. No neoplasm was identified.