Shigenori Takebayashi

Differentiation of newly diagnosed glioblastoma multiforme and intracranial diffuse large B-cell Lymphoma using (11)C-methionine and (18)F-FDG PET.

Purpose The aim of our study was to examine the usefulness of PET with 11C-methionine (MET) and 18F-fluorodeoxyglucose (FDG) in the differentiation of glioblastoma multiforme (GBM) and intracranial diffuse large B-cell lymphoma (DLBCL). Materials and Methods We evaluated 22 patients retrospectively with an enhancing brain tumor on MRI, including 15 GBM and 7 DLBCL, which was confirmed by histopathology. Dynamic PET scans with MET and FDG were performed for preoperative differential diagnosis. We assessed the images qualitatively and quantitatively. In quantitative assessment, the SUVmax was used on FDG PET and both late and early phases on MET PET. In addition, the ratio of SUVmax in the late and early phases on MET-PET was evaluated (&Dgr;SUVmax). Results SUVmax on FDG PET of DLBCL was significantly higher than that of GBM. Setting an SUVmax of 12.0 as the cutoff for differentiating DLBCL from GBM, 1 GBM and 1 DLBCL were found to be false-positive and false-negative, respectively. SUVmax in the late and early phases of MET-PET was not significantly different between DLBCL and GBM; however, we also found significant differences in &Dgr;SUVmax on MET-PET. Using &Dgr;SUVmax 1.17 as the cutoff, we could differentiate DLBCL from GBM completely. In the present study, &Dgr;SUVmax on MET-PET was slightly superior to SUVmax on FDG PET. Conclusions Both SUVmax on FDG PET and &Dgr;SUVmax on MET-PET were considered to be good diagnostic tests when encountering difficulties in this differential diagnosis.

Pilomotor seizures in mesial temporal lobe epilepsy: A case confirmed by intracranial EEG

We report the first case in which intracranial EEG was used to confirm pilomotor seizures of mesial temporal origin. A 41-year-old man who had pilomotor seizures in the left arm in addition to complex partial seizures was admitted for presurgical evaluation. Intracranial EEG revealed ictal discharges in the left mesial temporal area during left pilomotor seizures. Moreover, electrical stimulation of the left mesial temporal area induced a habitual pilomotor seizure. After anteromesial temporal lobectomy, the patient became seizure-free. The localizing and lateralizing value of pilomotor seizures are discussed.

Selective Propofol Injection into the M1 Segment of the Middle Cerebral Artery (MCA Wada Test) Reduces Adverse Effects and Enhances the Reliability of the Wada Test for Determining Speech Dominance

OBJECT The Wada test is had been the most reliable for determining speech dominance. Drugs injected into the internal carotid artery, however, may be heterogeneously distributed as the result of asymmetry of the anterior cerebral arteries and the presence of a fetal-type posterior cerebral artery. Variations in drug distribution could occasionally alter consciousness and complicate the evaluation of the test results. We examined selective propofol injection into the M1 segment of the middle cerebral artery (MCA Wada test). METHODS For the MCA Wada test (17 patients), 7 or 8 mg of propofol was injected via a microcatheter navigated into the M1 segment, and language function was evaluated by patient performing several tasks. The conventional Wada test (internal carotid artery [ICA] Wada test) was performed in four patients (both the ICA and MCA Wada tests were performed in one patient). The efficacy and adverse effects of both procedures were evaluated; all tests were performed by well-trained interventional neuroradiologists. RESULTS Immediately after propofol injection during the MCA Wada test, patients developed transient contralateral hemiplegia and transient aphasia (in the case of injection on the dominant side). Confusion and other severe adverse effects did not occur during the MCA Wada test, but two of four patients who underwent the ICA Wada test showed altered consciousness that affected the performance of the test. CONCLUSIONS The MCA Wada test is a feasible and reliable preoperative evaluation, if performed by a trained team of interventional neuroradiologists.

Long-term Effect and Predictive Factors of Motor Cortex and Spinal Cord Stimulation for Chronic Neuropathic Pain

The long-term effects of motor cortex stimulation (MCS) and spinal cord stimulation (SCS) remain unknown. To identify the long-term effects after MCS or SCS and determine any associated predictive factors for the outcomes. Fifty patients underwent MCS (n = 15) or SCS (n = 35) for chronic neuropathic pain. The degree of pain was assessed preoperatively, at 1, 6, and 12 months after surgery, and during the time of the last follow-up using Visual Analog Scale (VAS). Percentage of pain relief (PPR) was calculated, with “long-term effect” defined as PPR ≥ 30% and the presence of continued pain relief over 12 months. Outcomes were classified into excellent (PPR ≥ 70%) and good (PPR 30–69%) sub-categories. Long-term effects of MCS and SCS were observed in 53.3% and 57.1% of the patients, respectively. There were no predictive factors of long-term effects identified for any of the various preoperative conditions. However, the VAS at 1 month after surgery was significantly associated with the long-term effects in both MCS and SCS. All patients with an excellent outcome at 1 month after the surgery continued to exhibit these effects. In contrast, patients with the good outcome at 1 month exhibited a significant decrease in the effects at 6 months after surgery. The long-term effects of MCS and SCS were approximately 50% during the more than 8.5 and 3.5 years of follow-up, respectively. The VAS at 1 month after surgery may be a postoperative predictor of the long-term effects for both MCS and SCS.

[Supratentorial-infraoccipital approach supported by navigation and intraoperative magnetic resonance imaging for glioma located at the medial posterior temporal lobe: two case reports].

Resection of posteromedial temporal lobe lesions is challenging because surgical access through standard approaches requires excessive retraction or resection of temporal cortex. The utility of the supratentorial-infraoccipital approach for posteromedial temporal lobe lesions was first reported in 1995. Here, we report two cases of glioma located at the medial posterior temporal lobe. In both, total tumor removal was achieved by a supratentorial-infraoccipital approach using neuronavigation and intraoperative magnetic resonance imaging. Both patients presented with postoperative quadrantanopia because of optic radiation damage, but did not have worsening language, memory, or cognitive functions.