ABSTRACT
OBJECTIVE: The purpose of this study is to describe the neuroimaging (CT and MR imaging) findings in liver transplant patients who develop severe neurologic side effects during immunosuppressive therapy with tacrolimus and to correlate these findings with clinical signs and tacrolimus levels in blood. SUBJECTS AND METHODS: Brain CT and/or MR imaging was performed on six patients who developed neurologic symptoms while receiving tacrolimus in the post-transplant period. All patients were evaluated by the neurology staff, and imaging studies were independently interpreted by three neuroradiologists. Trough tacrolimus levels in blood were measured with the IMX immunoassay and were correlated with neurologic symptoms and imaging findings. RESULTS: Imaging abnormalities were observed in five of six patients during the course of their neurologic illnesses. For each patient, neurologic symptoms began when the tacrolimus level in blood was at a peak, exceeding the therapeutic limit in all but one case. In five patients, neurologic symptoms eventually resolved after the tacrolimus dose was reduced or after the drug was stopped. Multifocal low attenuation of white matter was the predominant finding seen on CT images, and matching hyperintense white matter foci were observed on long-TR MR images. In three patients, clinical recovery was accompanied by reversal of the white matter abnormalities seen on CT and MR images. CONCLUSION: Immunosuppressive therapy with tacrolimus may produce neurologic side effects that are associated with brain CT and MR imaging abnormalities. Resolution of symptoms and reversal of imaging findings occur when the tacrolimus dose is reduced.
Subject(s)
Immunosuppressive Agents/adverse effects , Magnetic Resonance Imaging , Nervous System Diseases/chemically induced , Nervous System Diseases/diagnosis , Tacrolimus/adverse effects , Tomography, X-Ray Computed , Adult , Brain/diagnostic imaging , Brain/pathology , Female , Humans , Liver Transplantation , Male , Middle Aged , Nervous System Diseases/diagnostic imagingABSTRACT
Imaging findings in two children with molybdenum cofactor deficiency included, in one, diffuse low attenuation on CT in cerebral white matter, caudate nuclei, and thalami soon after birth. MR in both patients later demonstrated progressive widening of the sulci, ventricles, and cisterna magna, and loss of brain volume. MR finally showed cessation of myelination at 31 months and 16 weeks of age.
Subject(s)
Brain Diseases, Metabolic/genetics , Coenzymes , Magnetic Resonance Imaging , Metalloproteins/metabolism , Pteridines/metabolism , Tomography, X-Ray Computed , Atrophy , Brain/pathology , Brain Diseases, Metabolic/diagnosis , Diagnosis, Differential , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Molybdenum Cofactors , Nerve Fibers, Myelinated/pathologyABSTRACT
PURPOSE: To determine the features of the cardiac cycle-related cerebrospinal fluid (CSF) flow pulsations in with Chiari I malformation before and after decompressive surgery. MATERIALS AND METHODS: Fifteen patients and 23 healthy subjects underwent cine phase-contrast magnetic resonance imaging. Ten patients were also examined after decompressive surgery. Four regions of interest were selected in the upper cervical subarachnoid space and premedullary cistern. Velocity and fraction of the cardiac cycle waveforms were plotted, and amplitude, temporal, and CSF displacement parameters were assessed. RESULTS: In the Chiari I patients, impaired systolic and unaltered diastolic CSF flow pulsations immediately below the foramen magnum were identified. After surgery, the systolic flow pulsations immediately below the foramen magnum improved. Good correlation with post-surgical improvement was observed. CONCLUSION: CSF flow waveform analysis helps demonstrate abnormalities in CSF flow at the foramen magnum and the benefits of decompressive surgery in patients with the Chiari I malformation.
Subject(s)
Arnold-Chiari Malformation/physiopathology , Cerebrospinal Fluid/physiology , Magnetic Resonance Imaging , Adolescent , Adult , Arnold-Chiari Malformation/surgery , Child , Female , Humans , Magnetic Resonance Imaging/methods , Male , Middle Aged , RheologyABSTRACT
OBJECTIVE: The purpose of this study was to determine by MR imaging the prevalence and types of dysraphic abnormalities of the spinal cord (i.e., myelodysplasias) associated with urogenital and anorectal malformations of childhood. MATERIALS AND METHODS: Since 1987, 92 patients with imperforate anus complex, cloacal malformation, and cloacal exstrophy have had MR imaging as a screening examination for occult dysraphic myelodysplasia. The prevalence and types of myelodysplasia were determined for each group. RESULTS: The prevalence of dysraphic myelodysplasia in each group of children was 17% (1/6) for low imperforate anus (ectopic anus), 34% (11/32) for high imperforate anus (with fistulization), 46% (19/41) for cloacal malformation, and 100% (13/13) for cloacal exstrophy. The most common abnormalities in each group were tethered cord with intradural or filar lipoma in imperforate anus; low-placed or dysplastic conus medullaris and tethered cord with lipoma or myelolipoma in cloacal malformation; and lipomyelocele, lipomyelomeningocele, or lipomyelocystocele in cloacal exstrophy. CONCLUSION: Our results show that the prevalence of myelodysplasia as seen on MR imaging is high in patients with urogenital and anorectal anomalies.
