Clinical, neurodiagnostic, and MR findings in children with spinal and brain stem multiple sclerosis

PURPOSE: To describe the clinical, neurodiagnostic, and MR findings in seven children with brain stem and spinal multiple sclerosis. METHODS: Spinal or brain stem multiple sclerosis was diagnosed in seven children between 1986 and 1992. All patients had neurologic and MR examinations as well as neurodiagnostic testing, including spinal fluid analysis and brain stem and auditory evoked potentials. RESULTS: Three children had clinical findings and masslike lesions in the brain stem (two) or spinal cord (one) suggestive of neoplasm, which prompted biopsy (two) or radiation therapy (one). Five of six patients with spinal involvement had cord swelling with increased signal on T2-weighted images over at least three cord segments, and two children had essentially holocord involvement. Three children had normal cranial MR at presentation. CONCLUSIONS: Multiple sclerosis involvement of the brain stem and spinal cord may be associated with extensive swelling and MR signal changes suggestive of neoplasm without typical cerebral white matter abnormalities. Serial clinical and neuroimaging examinations may be necessary to make a definitive diagnosis of multiple sclerosis in children.     

Magnetic resonance in HTL-I associated myelopathy. Leukoencephalopathy and spinal cord atrophy

Cerebral white matter lesions and spinal cord atrophy have been frequently reported in patients with HTLV-I associated myelopathy (HAM). The exact frequency and the clinical relevance of these findings still remain to be elucidated. Twenty-nine patients with HAM were studied by magnetic resonance imaging of the brain and spine. Cerebral white matter lesions equal or over 3 mm in diameter were considered abnormal. The spinal cord size was evaluated using an index we have called "spinal cord index". The radiological findings were correlated to the clinical features of the myelopathy. Cerebral white matter lesions occurred in 52% of the patients, and spinal cord atrophy in 74%. There was no significant correlation between these abnormalities and the clinical features studied. These findings suggest that the resonance imaging is a useful method for detection of cerebral and spinal cord abnormalities in HAM patients. The absence of correlation between cerebral white matter lesions and either patient age or risk factors for cardiovascular disease suggests a possible association between the leukoencephalopathy and the infection.     

Beneficial effects of acetazolamide on paroxysmal attacks of girdle sensation in multiple sclerosis

A 56-year-old woman with a 40-year history of multiple sclerosis (MS) developed paroxysmal attacks of girdle sensation in the Th5-6 dermatomes. The attacks lasted 20-60 minutes and occured up to three times per week. T2-weighted MR imaging of the spinal cord showed high intensity area from Th5 to Th8. Electrocardiography, echocardiography and laboratory findings did not indicate ischemic heart disease; therefore, the paroxysms were attributed to the spinal cord lesions. Attacks were successfully suppressed by acetazolamide 250 mg/day. Although carbamazepine is frequently used to treat paroxysmal attacks in MS, we would like to suggest that acetazolamide may also be beneficial in some patients with paroxysmal symptoms.     

The low sensitivity of fluid-attenuated inversion-recovery MR in the detection of multiple sclerosis of the spinal cord

PURPOSE: To confirm the expected superiority of fluid-attenuated inversion-recovery (FLAIR) over conventional fast spin-echo MR imaging in the detection of multiple sclerosis (MS) of the spinal cord. METHODS: Fifteen subjects with known MS involving the spinal cord and brain were studied prospectively. The entire cord was imaged with a phased-array coil on a 1.5-T MR system. Sagittal T1-weighted and fast spin-echo proton density- and T2-weighted images were followed by fast FLAIR images. FLAIR parameters were varied to optimize lesion conspicuity with optimal inversion times (TIs) ranging from 2400 to 2600. Lesion conspicuity and detection were compared between the fast spin-echo and FLAIR images by three radiologists who reached agreement by consensus. RESULTS: The FLAIR technique effectively suppressed cerebrospinal fluid (CSF) signal and reduced CSF pulsation and truncation artifacts in all cases. Shorter imaging parameters (repetition time of 4000 to 6000, TI of 1500 to 2000) uniformly decreased lesion conspicuity in all subjects. Of 11 cord lesions in five subjects imaged with the longer parameters (repetition time of 8000 to 11,000, TI of 2400 to 2600), three were not seen on FLAIR images, four were less conspicuous on FLAIR images, and four were seen equally or better on FLAIR images. CONCLUSION: Although successful in suppressing CSF signal and reducing imaging artifacts, fast FLAIR imaging appears unreliable in the detection of MS lesions in the spinal cord.     

Diagnostic and surgical management of spinal dural arteriovenous fistulas

OBJECTIVE: A retrospective review was conducted to compare magnetic resonance (MR) and conventional spinal angiographic images and to investigate the outcome of our treatment protocol for patients with spinal dural arteriovenous fistulas (DAVFs). MATERIALS AND METHODS: Nine patients with a diagnosis of DAVF based on clinical myelopathy and preoperative MR imaging (MRI) and MR angiography (MRA) findings were treated at our institution by the senior author (BAG). All nine patients initially presented with progressive myelopathy. Preoperative MRI revealed T2-weighted signal abnormalities in all patients, and MRA was diagnostic in all patients. Each patient underwent a laminectomy and ligation of the arterialized draining vein. Selective spinal angiograms were used to confirm the level of fistula immediately before the surgical procedure was performed and to document complete obliteration after clip ligation of the medullary draining vein. Follow-up MRI and MRA were performed approximately 2 months postoperatively. RESULTS: MRI T2-weighted signal hyperintensity improved after surgery in all nine patients. Postoperatively, progression of motor weakness and gait difficulty was halted and some improvement was observed in all patients. No patient was neurologically normal, however. To date, there has been no clinical or MRA evidence of recurrence in any patient. CONCLUSION: Preoperative MRA and intraoperative spinal x-ray angiography present as an effective combination for diagnosing and intraoperatively confirming DAVF. Both T1-weighted enhancement and T2-weighted signal hyperintensity on MR images improved after the obliteration of the DAVFs and correlated with clinical improvement in all nine patients. MRA provides adequate visualization and localization of spinal DAVFs and may serve as a useful noninvasive tool for diagnosing and following patients with spinal DAVFs in the future.     

Agouti serum L-asparaginase. II. Chromatographic fractionation and characterization of the enzymatically active component

Bladder and urethral innervation was studied in 52 patients with multiple sclerosis using a signal tracing technique (evoked reflex latency measurement). The majority of the patients showed prolonged signal transit times indicative of demyelinating plaques localised to the lumbosacral spinal cord. Futhermore, impairment of the corticospinal innervation of the pudendal nucleus was found in 29 patients indicating lesions of the pyramidal tract.     

Spinal cord decompression via microsurgical anterior foraminotomy for spondylotic cervical myelopathy

A microsurgical anterior foraminotomy, as a direct decompressive and motion-segment preserving technique, has been developed by the author and used successfully in many patients with spondylotic cervical radiculopathy for the past several years. From the author's increasing experience with anterior foraminotomy for cervical radiculopathy, it was noted that the spinal cord canal could be effectively decompressed utilizing the holes of anterior foraminotomy. This new technique accomplishes widening of the spinal cord canal anteriorly to the spinal cord in the transverse and longitudinal axis by direct removal of the compressive lesions through the holes of unilateral anterior foraminotomies. This technique does not require bone fusion or postoperative immobilization. 14 patients with spondylotic cervical myelopathy have been treated by this technique. 9 were males and 5 were females, and all presented with cervical myelopathy with or without radiculopathy. Age ranged from 32 to 68 years (median 55 years). 6 patients had spinal cord compression at one level, six patients experienced it at two levels, and two patients had it at three levels. Postoperatively, all patients showed improvement in their myelopathic symptomatology as well as gaining relief of their radicular symptoms. Corresponding MR scans confirmed satisfactory anatomical decompression in all patients. Postoperative dynamic roentgenograms confirmed spinal stability in all patients as well. Patients stayed in the hospital overnight postoperatively, and cervical braces were not used. This new surgical technique has shown excellent clinical outcomes with fast recovery and adequate anatomical decompression in 14 patients with spondylotic cervical myelopathy.     

Spinal myoclonus: report of four cases

Four cases of spinal myoclonus are described, three males and one female. The mean age was 51 years (28-75 years). The mean time between the onset of the myelopathy and the myoclonic jerks was 4.3 months (1-8 months). The involuntary movements were determined by trauma, Devic's disease, tuberculous myelopathy and tumor. Three patients had spastic paraplegia with bilateral myoclonus more evident on the right side. The fourth patient had a flaccid paraplegia with symmetrical jerks. The data suggest that different processes (trauma, demyelinating, infection and tumor) affecting the spinal cord may cause the same type of involuntary movements.     

Demyelinating disease versus tumor in surgical neuropathology. Clues to a correct pathological diagnosis

Clinical presentations as well as radiological and histopathological findings in biopsies from patients with multiple sclerosis (MS) or other demyelinating disorders of the central nervous system are sometimes misleading, resulting in an erroneous diagnosis of brain or spinal cord tumor. We report 17 patients who presented with symptoms mimicking those of brain (14 cases) or spinal cord (three cases) tumors. Computerized tomography or magnetic resonance imaging studies or both were interpreted as consistent with a tumor in each case. All patients underwent surgery, and all 17 pathological specimens were eventually diagnosed as showing demyelinating disease, usually consistent with MS. In each case we examined a variety of histological features and immunohistochemical studies and addressed their relative importance in considering the diagnosis of MS. All cases showed perivascular lymphocytic inflammation with variable amounts of macrophage infiltration, necrosis, and edema. The hypercellularity of the lesions and the presence of atypical reactive astrocytes with mitotic figures were the disturbing features that might have led to the erroneous diagnosis of an astrocytic neoplasm. Immunohistochemistry for astrocytic (glial fibrillary acidic protein) and macrophage (HAM-56) markers are helpful in evaluating biopsies. Our results emphasize the need to perform special stains (i.e., for myelin and axons) that demonstrate myelin loss and relative preservation of axons and allow a correct diagnosis.     

Radiation myelopathy: a clinicopathological study with special reference to correlation between MRI findings and neuropathology

We describe magnetic resonance imaging (MRI) and neuropathological findings in a patient with chronic progressive radiation myelopathy (CPRM). An 81-year-old man with esophageal cancer underwent radiotherapy. Four years later he developed a progressive neurological deficit below the irradiated level of the spinal cord. Neurological examination revealed spastic paraplegia. MRI findings showed an area of high signal intensity on T2-weighted images of the thoracic spinal cord. On the basis of clinical and MRI findings, we diagnosed his condition as CPRM. MRI performed thirteen months after onset of neurological signs revealed mild atrophy of the spinal cord detected on T1-weighted images and an area of high signal intensity within the spinal cord detected on T2-weighted images. Neuropathological examination revealed findings consistent with radiation myelopathy. We speculate that the area of high signal intensity within the spinal cord detected on T2-weighted images might be a result of proliferation of small vessels, which was discovered upon autopsy.     

Critical care medicine

A postmortem case of HTLV-I associated myelopathy (HAM)/tropical spastic paraparesis (TSP) with a history of remission and exacerbation of neurological signs and symptoms, resembling those of multiple sclerosis is reported. MRI analysis revealed lesions in the periventricular white matter in addition to atrophy of the thoracic spinal cord, characteristic of HAM/TSP. The cerebral periventricular areas consisted of ill-defined paucity of myelin sheaths with astrocytic gliosis and hyaline thickening of blood vessels. The poorly demarcated white matter lesions found in both brain and spinal cord were different from plaques found in multiple sclerosis. It is suggested that, in some cases of HAM/TSP, inflammatory lesions that destroy myelin can involve not only the spinal cord but also the cerebral periventricular white matter.     

Magnetic resonance imaging of experimental subacute spinal cord compression

STUDY DESIGN: Subacute compression of the spinal cord was applied to rats. The animals were chronologically observed using magnetic resonance imaging for more than 8 weeks after surgery and were killed for histopathologic examination. OBJECTIVES: To investigate the correlation of changes in signal intensity on magnetic resonance images with those observed in histopathologic study and with the degree of spinal cord compression and paralysis. SUMMARY OF BACKGROUND DATA: No consensus has been reached concerning the correlation of magnetic resonance images to clinical symptoms of compressive myelopathy. Few reports are available in which magnetic resonance imaging findings are compared with histopathologic features in chronic or subacute experiments. METHODS: In rats under general anesthesia, the T11 lamina was thinned and a slow increase in volume was applied. Hind limb paralysis appeared 1 week after the procedure and spontaneously subsided thereafter. The degree of spinal compression and signal intensity was observed chronologically using magnetic resonance imaging. The signal intensity on the final MR images was rated on a four-point scale and compared with histopathologic findings. RESULTS: As spinal compression increased, the incidence of high signal intensity on long spin-echo images became higher. Low signal intensities on short spin-echo images were visible in animals in which compression and paralysis were the most severe. In these animals, cavitation and a dilated central canal were visible. High signal intensities on long spin-echo images reflected various pathologic changes. CONCLUSIONS: Changes in signal intensity on MR images are visible after the induction of myelopathy by high-pressure compression. These signal intensities may be useful in predicting the outcome of compressive myelopathy.     

Increased calpain expression in activated glial and inflammatory cells in experimental allergic encephalomyelitis

In demyelinating diseases such as multiple sclerosis (MS), myelin membrane structure is destabilized as myelin proteins are lost. Calcium-activated neutral proteinase (calpain) is believed to participate in myelin protein degradation because known calpain substrates [myelin basic protein (MBP); myelin-associated glycoprotein] are degraded in this disease. In exploring the role of calpain in demyelinating diseases, we examined calpain expression in Lewis rats with acute experimental allergic encephalomyelitis (EAE), an animal model for MS. Using double-immunofluorescence labeling to identify cells expressing calpain, we labeled rat spinal cord sections for calpain with a polyclonal millicalpain antibody and with mAbs for glial (GFAP, OX42, GalC) and inflammatory (CD2, ED2, interferon gamma) cell-specific markers. Calpain expression was increased in activated microglia (OX42) and infiltrating macrophages (ED2) compared with controls. Oligodendrocytes (galactocerebroside) and astrocytes (GFAP) had constitutive calpain expression in normal spinal cords whereas reactive astrocytes in spinal cords from animals with EAE exhibited markedly increased calpain levels compared with astrocytes in adjuvant controls. Oligodendrocytes in spinal cords from rats with EAE expressed increased calpain levels in some areas, but overall the increases in calpain expression were small. Most T cells in grade 4 EAE expressed low levels of calpain, but interferon gamma-positive cells demonstrated markedly increased calpain expression. These findings suggest that increased levels of calpain in activated glial and inflammatory cells in EAE may contribute to myelin destruction in demyelinating diseases such as MS.     

Specific changes in human brain following reperfusion after cardiac arrest

BACKGROUND AND PURPOSE: Very few reports are available on serial changes in human brain after cardiac arrest. The primary objective of this study is to investigate sequential neuroradiological changes in patients remaining in a persistent vegetative state following resuscitation after cardiac arrest. METHODS: We repeatedly studied eight vegetative patients resuscitated from unexpected out-of-hospital cardiac arrest using computed tomographic (CT) scanning and high-field magnetic resonance (MR) imaging at 1.5 T. RESULTS: In seven of the eight patients, CT scans obtained between days 2 and 6 features symmetrical low-density lesions in the bilateral caudate, lenticular, and/or thalamic nuclei. These ischemic lesions were persistently of low density on serial CT scans. In these seven patients, MR images demonstrated what were thought to be hemoglobin degradation products derived from minor hemorrhages localized in the bilateral basal ganglia, thalami, and/or substantia nigra. Diffuse brain edema in the acute stage and diffuse brain atrophy in the chronic stage were consistent neuroradiological findings. No abnormal enhanced lesions were demonstrated by CT scans. CONCLUSIONS: The most characteristic findings on high-field MR images were symmetrical lesions in the bilateral basal ganglia, thalami, and/or substantia nigra with specific changes suggestive of minor hemorrhages that were not evident on CT scans. We speculate that these minor hemorrhages result from diapedesis of red blood cells in these regions during the reperfusion period through the endothelium disrupted by ischemia-reperfusion insult.     

MR of spinal cord ganglioglioma

PURPOSE: Our purpose was to describe the MR imaging features in a series of spinal intramedullary gangliogliomas and to compare these findings with the MR features of intramedullary astrocytomas and ependymomas. METHODS: A retrospective analysis was performed of 76 MR examinations in 27 patients with histologically proved spinal ganglioglioma; these were then compared with imaging findings in a representative sample of histologically proved spinal cord astrocytomas and ependymomas. RESULTS: Statistically significant observations regarding spinal gangliogliomas included young age of the patients (mean, 12 years), long tumor length, presence of tumoral cyst, presence of bone erosion and scoliosis, absence of edema, presence of mixed signal intensity on T1-weighted images, and presence of patchy enhancement and cord surface enhancement. A trend (not statistically significant) was noted for holocord involvement and lack of magnetic susceptibility. CONCLUSION: Spinal ganglioglioma can be strongly suspected if MR images reflect the above criteria; however, the ultimate diagnosis still depends on radical resection and appropriate histopathologic investigation.     

Spontaneous thoracic spinal cord herniation. A case report

STUDY DESIGN: This is a case report. OBJECTIVE: To focus attention on spontaneous spinal cord herniation as a rare cause of myelopathy that can be diagnosed preoperatively and can be corrected surgically. SUMMARY OF BACKGROUND DATA: A 34-year-old woman presented with spastic paraparesis. Magnetic resonance imaging scan of the thoracic spine revealed anterior displacement and tethering of the cord at T6-T7 and a dorsal intradural arachnoid cyst. Excision of the cyst was performed without improvement in symptomatology. During reoperation the thoracic spinal cord hernia was discovered and was reduced intradurally. METHODS: The authors describe the clinical, radiographic, and surgical findings of this patient and review the findings from other reported cases. They discuss the proposed theories for the pathophysiology of the cord herniation and the surgical management. RESULTS: The patient had idiopathic thoracic spinal cord herniation as there was no history of previous spine surgery or injury. The authors believe that the cord herniated through a congenital dural defect, which resulted in the development of a pseudoarachnoid cyst dorsally to the hernia. The patient improved after intradural reduction of the hernia and closure of the dural defect. CONCLUSION: Idiopathic spinal cord herniation should be recognized as a cause of progressive myelopathy that can be managed successfully with microsurgical techniques.     

Neuroimaging and pathology of the spinal cord in compressive cervical myelopathy

Magnetic resonance imaging (MRI) has enabled us to see the spinal intramedullary pathology as differences in signal intensity. Intramedullary high intensity lesions were observed on T2-weighted MRI in patients with cervical spondylotic myelopathy (20.0%) and ossification of the posterior longitudinal ligament (OPLL) of the cervical spine (25.7%). The frequency of this findings was proportional to the clinical severity of myelopathy and degree of spinal cord compression. The pathophysiological basis of such signal abnormality was presumed to vary from acute edema to chronic myelomalacia. The intramedullary lesion on MRI is considered to be the main site of lesion responsible for the neurological symptom because of a good correlation between the neurological level and high intensity level. We found from nine autopsy cases of OPLL that there are distinct differences in severity and extent of pathological changes between the spinal cord with a boomerang-shaped cross-section and that with a triangular-shaped cross-section. In the boomerang-shaped cases, major pathological changes were restricted to the gray matter and the white matter was relatively well preserved. Secondary wallerian degeneration was restricted to the fasciclus cuneatus the fibers of which were derived from the affected segments. In the cases of a triangular shape, pathological changes were more severe, both white and gray matter were involved. There were severe pathological changes over more than one segment, and both descending degeneration of the lateral pyramidal tracts and ascending degeneration of the posterior column, including the fasciclus gracilis, were observed. In conclusion, it is clinically very important to understand the pathological basis of the compressed spinal cord on neuroimages.     

Autopsy findings of atheromatous embolism to the spinal cord]

To study vascular lesions of the spinal cord in the elderly, a pathological study of atheromatous emboli in the spinal cord was done. Among 604 patients examined at autopsy, atheromatous emboli of the spinal cord were found in 7 (1.2%). The average age of these patients was 76 years. The most common underlying disorders in these patients were hypertension, severe aortic atherosclerosis, and diabetes mellitus. Atheromatous emboli were also often found in the arteries of the kidneys, spleen, pancreas, and colon. The small arteries of the spinal arachnoid at the lumbosacral level were most frequently affected by the atheromatous emboli. Two patients had spinal-cord infarctions associated with atheromatous emboli: one had a cystic infarction of the lateral column at the T9 segment, and the other had cystic infarctions of the lateral column at the C7 and T3 segments. The low incidence of spinal cord infarction was attributed to good collateral circulation in the spinal cord. Atheromatous embolism should be considered as a possible cause of vascular lesions of the spinal cord in elderly persons with aortic atherosclerosis.     

Proton MR spectroscopy and magnetization transfer ratio in multiple sclerosis: correlative findings of active versus irreversible plaque disease

PURPOSE: To characterize plaques of multiple sclerosis (MS) using both proton MR spectroscopy and magnetization transfer (MT) imaging. METHODS: The magnetization transfer ratio (MTR) was calculated from two series of three-dimensional gradient-recalled acquisition in the steady state (GRASS) images obtained with and without an MT saturation pulse. Proton spectra were acquired using the point-resolved spectroscopy (PRESS) sequence with a voxel size of 1.5 x 1.5 x 1.5 cm3. A total of 28 spectra were obtained in 13 patients who had clinically definitive MS. The spectra were analyzed together with the MTR. RESULTS: A positive relationship was found between the N-acetylaspartate (NAA)/creatine (Cr) ratio and the MTR in MS plaques, whereas no significant correlation was found between the metabolite ratios and the signal intensity on fast spin-echo T2-weighted MR images. CONCLUSION: Small changes in the MTR of MS plaques relative to the MTR of normal white matter may reflect inflammatory changes and edema, whereas larger changes in MTR correlate with decreased NAA/Cr ratio and therefore suggest demyelination and irreversible damage from chronic MS plaques.     

Myelopathy after intrathecal chemotherapy. A case report with unique magnetic resonance imaging changes

BACKGROUND: Paraplegia caused by intrathecal chemotherapy has no known pathognomonic features and is a diagnosis of exclusion. METHODS: The authors reported the clinical and neuroimaging findings in one patient with this syndrome. RESULTS: The patient had severe paraplegia with urinary retention and impaired pain and touch sensation below T-10 with sparing of proprioception and vibration sense. Magnetic resonance imaging (MRI) scan showed diminished intensity throughout the central cervical spinal cord. Post-gadopentetate dimeglumine enhancement was scattered throughout the cervical spinal cord and in two areas of the dorsal spinal cord. Axial views of the cervical spinal cord showed that this enhancement was limited to the lateral columns. CONCLUSIONS: The MRI in myelopathy due to intrathecal chemotherapy may show a unique pattern of postgadopentetate dimeglumine enhancement limited to the lateral columns of the spinal cord. However, two recently encountered patients with the same syndrome did not show similar changes.