Choroid plexus papillomas (CPPs) are usually not malignant and occur in less than 1% of brain tumors in patients of all ages. They represent 3% of childhood intracranial neoplasms with a predilection in younger ages. Papillomas have an indolent course and carry a good long-term outcome if gross total surgical resection is achieved. However malignant evolution may occur, with a 10-30% incidence. Chemotherapy has been used with varied degrees of success. Most series are very small, some are only limited to case reports and cannot lead to guidelines or therapeutic recommendations. We are reporting the first case of recurrent CPP treated with 5 mg/kg of bevacizumab administered once every two weeks. Complete patient evaluations with follow-up contrast-enhanced magnetic resonance imaging (MRI) scans were obtained after the initial two treatments and every 8 weeks thereafter. Only after two treatments, the MRI scans showed radiological stabilization of the tumor, and the patient achieved an excellent clinical response with significant resolution of all skin lesions.
Magnetic resonance (MR) imaging of the cervical spine with axial, low flip angle three-dimensional (3D) gradientecho sequences is limited by long acquisition times and also by increased sensitivity to extrinsic and intrinsic magnetic field inhomogeneity, magnetic susceptibility differences, chemical shifts, and cerebrospinal fluid pulsatility. We attempted to assess the performance of gadolinium-enhanced, magnetization transfer (MT) prepulsed 3D fast gradient-echo sequences in demonstrating spondylotic changes of the cervical spine. Twenty patients with known cervical spine spondylosis were prospectively imaged in the axial plane using two gradient-echo-based MR techniques: 3D fast field echo (FFE) and gadolinium-enhanced, MT prepulsed, segmented turbo field echo (TFE). An average of 58 neural foramina on the 3D FFE images and 47 neural foramina on the contrast-enhanced TFE images were judged to be narrowed. The degree of neural foraminal narrowing was significantly less on the contrastenhanced TFE images compared with the FFE images (P <0 AXIAL THREE-DIMENSIONAL (3D) gradient-echo sequences with myelogram-like contrast (low flip angle) are currently the most widely accepted MR imaging techniques for evaluating the lateral recesses and the neural foramina in degenerative disease of the cervical spine (1,2). However, these techniques remain limited by long acquisition times and also by increased sensitivity to extrinsic and intrinsic magnetic field inhomogeneity, magnetic susceptibility differences, chemical shifts, and cerebrospinal fluid (CSF) pulsatility (3,4). Related image artifacts and signal degradation can be minimized by using the shortest possible repetition and echo times (5)..Optimized magnetization transfer (MT) prepulsed, low flip angle, segmented 3D turbo field echo (TFE) MR imaging can provide myelogram-like contrast at shorter echo times and acquisition times, thus reducing related image artifacts (6).Clinical experience with the MT prepulsed 3D gradient-echo techniques has demonstrated a reduction in the signal intensity of neural foraminal contents, as well as contrast between the contents and bony walls of the neural foramina (5,7). This reduction in contrast can lead to poor representation of the diseased foramen.Based on previous success with the use of intravenous gadolinium to improve contrast between contents and bony walls of the neural foramina (8), we attempted to assess the performance of gadolinium-enhanced, MT prepulsed, low flip angle, segmented 3D TFE techniques in imaging the degenerated cervical spine (Fig. 1).We hypothesize that the combination of gadolinium enhancement and fast 3D TFE techniques can overcome some of the limitations of the more widely accepted low flip angle 3D gradient-echo sequences. MATERIALS AND METHODSMR imaging was performed on a 1.5 T actively shielded superconducting magnet with peak gradient amplitude of 15 mT ⅐ m -1 and a maximum slew rate of 16.7 mT ⅐ m -1 ⅐ ms -1. MR images of the cervical spine were obtained with a standard quadrature phased-array c...
Magnetic resonance (MR) imaging of the cervical spine with axial, low flip angle three‐dimensional (3D) gradient‐echo sequences is limited by long acquisition times and also by increased sensitivity to extrinsic and intrinsic magnetic field inhomogeneity, magnetic susceptibility differences, chemical shifts, and cerebrospinal fluid pulsatility. We attempted to assess the performance of gadolinium‐enhanced, magnetization transfer (MT) prepulsed 3D fast gradient‐echo sequences in demonstrating spondylotic changes of the cervical spine. Twenty patients with known cervical spine spondylosis were prospectively imaged in the axial plane using two gradient‐echo‐based MR techniques: 3D fast field echo (FFE) and gadolinium‐enhanced, MT prepulsed, segmented turbo field echo (TFE). An average of 58 neural foramina on the 3D FFE images and 47 neural foramina on the contrast‐enhanced TFE images were judged to be narrowed. The degree of neural foraminal narrowing was significantly less on the contrast‐enhanced TFE images compared with the FFE images (P <0.001). Contrast‐enhanced, MT prepulsed, segmented 3D TFE MR imaging has potential for ameliorating some of the limitations encountered in the more widely used gradient‐echo techniques. J. Magn. Reson. Imaging 2000;11:294–298. © 2000 Wiley‐Liss, Inc.
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