Cognitive function and diffusion tensor imaging were assessed in a group of 12 patients with early relapsing-remitting multiple sclerosis (disease duration

With the advent of fast imaging hardware and specialized software, additional non-invasive magnetic resonance characterization of tumors has become available through proton magnetic resonance spectroscopy (MRS), hemodynamic imaging and diffusion-weighted imaging (DWI). Thus, patterns could be discerned to discriminate different types of tumors and even to infer their possible evolution in time. The purpose of this study was to investigate the correlation between MRS, DWI, histopathology and Ki-67 labeling index in a large number of brain tumors. Localized proton spectra were obtained in 47 patients with brain tumors who subsequently underwent surgery (biopsy or tumor removal). We performed MRS with short echo-time (30 ms) and metabolic values in spectra were measured using an external software with 25 peaks. In all patients who had DWI, we measured apparent diffusion coefficients (ADC) in the same region of interest (ROI) where the voxel in MRS was located. In most tumors the histological diagnosis and Ki-67 labeling index had been determined on our original surgical specimen. Cho/Cr, (Lip+Mm)/Cr, NAA/(Cho+Cr) and Glx/Cr indexes in MRS allowed discriminating between low- and high-grade gliomas and metastases (MTs). Likewise, absolute ADC values differentiated low- from high-grade gliomas expressed by Ki-67 labeling index. A novel finding was that high Glx/Cr in vivo MRS index (similar to other known indexes) was a good predictor of tumor grading.

Background: Traumatic brain injury (TBI) can induce long-term severe disorders of consciousness. Evidence suggests an underlying dopaminergic deficit. Dopamine agonists may therefore play an important role in recovery of consciousness. Objective: To explore the response to continuous subcutaneous administration of apomorphine in a patient who had remained in minimally conscious state for 104 days and to evaluate the anatomical substrate of the effect. Design: A prospective, open-label, daily treatment, dose-escalation single case clinical study, with retrospective diffusion tensor image (DTI) evaluation. Results: On the fist day of treatment, the patient was able to move his limbs on command and answer yes/no questions which had not been the case prior to apomorphine administration. Subsequently there was a full recovery of consciousness and substantial functional recovery that was sustained even after apomorphine discontinuation. At the highest dose, mild dyskinesias were observed. These resolved with a lowering of the dose. DTI demonstrated a decrease of thalamocortical and corticothalamic projections in this MCS patient compared to normal volunteers. Conclusion: Although this is an open-label single-patient case report, the data are consistent with the theory that a dopaminergic deficit underlies MCS and that it may be overcome with apomorphine administration.

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