We used localized 1H-magnetic resonance spectroscopy (MRS) to study the metabolic changes in the brains of patients with migraine during the interictal period. Measurement of metabolite levels in the occipital visual cortex in six normal subjects and six patients disclosed high lactate levels in the five patients who had experienced a migraine attack within the previous 2 months. One patient who had not experienced a migraine attack in the previous 4 years did not show a lactate peak. We speculate that anaerobic glycolysis occurs in the brains of patients with migraine during the interictal period, and a long attack-free period may normalize the subclinical metabolic disturbance.

Recently, two methods have been proposed for regional cerebral blood flow (rCBF) quantitation using [123I]iodoamphetamine (IMP) and single-photon emission computed tomography (SPECT). The table look-up (TLU) method has been shown to provide both rCBF and volume of distribution, Vd, images from two SPECT scans, while a single-scan autoradiographic (ARG) technique provided rCBF using a fixed and assumed Vd. In both methods, a single blood sample was referred to calibrate the previously determined standard input function. The present multicenter project was designed to evaluate the accuracy of both methods for use as clinical investigative tools. Ten independent institutions performed [123I]IMP-SPECT studies according to both methods in 76 subjects (10 normal volunteers, 32 patients with cerebrovascular disease, and 34 patients with other diseases). Calculated rCBF values were compared with those obtained by the following reference methods available in the participating institutions; [15O] H2O positron emission tomography (PET) (five institutions), [133Xe]SPECT (four institutions), and the [123I]IMP microsphere method (three institutions). Both ARG and TLU methods provided rCBF values that were significantly correlated with those measured by the [15O] H2O PET technique (p < 0.001 for all subjects; overall regression equation, y = 15.14 + 0.54x) and those measured by the [123I]IMP-microsphere method (p < 0.001 for all subjects: y = 2.0 + 0.80x). Significant correlation (p < 0.05) was observed in 18 of 24 subjects studied with the [133Xe] SPECT reference technique (overall regression equation, y = 15.0 + 0.55x). Mean cortical gray matter rCBF in a group of normal subject was 43.9 +/- 3.3 and 43.4 +/- 2.0 ml/min/100 g for the ARG and TLU methods, respectively. Regional Vd of [123I]IMP estimated by the TLU method was 45 ml/ml +/- 20% in the normal cortical region. Close agreement between ARG and TLU rCBF values was observed (y = -3.21 + 1.07x, r = 0.97), confirming the validity of assuming a fixed Vd in the ARG method. Results of this study demonstrate that both the ARG and TLU methods accurately and reliably estimate rCBF in a variety of clinical settings.

This study describes an effective method for verifying line spread function (LSF) and point spread function (PSF) measured in computed tomography (CT). The CT image of an assumed object function is known to be calculable using LSF or PSF based on a model for the spatial resolution in a linear imaging system. Therefore, the validities of LSF and PSF would be confirmed by comparing the computed images with the images obtained by scanning phantoms corresponding to the object function. Differences between computed and measured images will depend on the accuracy of the LSF and PSF used in the calculations. First, we measured LSF in our scanner, and derived the two-dimensional PSF in the scan plane from the LSE Second, we scanned the phantom including uniform cylindrical objects parallel to the long axis of a patient's body (z direction). Measured images of such a phantom were characterized according to the spatial resolution in the scan plane, and did not depend on the spatial resolution in the z direction. Third, images were calculated by two-dimensionally convolving the true object as a function of space with the PSF. As a result of comparing computed images with measured ones, good agreement was found and was demonstrated by image subtraction. As a criterion for evaluating quantitatively the overall differences of images, we defined the normalized standard deviation (SD) in the differences between computed and measured images. These normalized SDs were less than 5.0% (ranging from 1.3% to 4.8%) for three types of image reconstruction kernels and for various diameters of cylindrical objects, indicating the high accuracy of PSF and LSF that resulted in successful measurements. Further, we also obtained another LSF utilizing an inappropriate manner, and calculated the images as above. This time, the computed images did not agree with the measured ones. The normalized SDs were 6.0% or more (ranging from 6.0% to 13.8%), indicating the inaccuracy of the PSF and LSE We could verify LSFs and PSFs for three types of reconstruction kernels, and demonstrated differences between modulation transfer functions (MTFs) derived from validated LSFs and inaccurate LSFs. Our technique requires a simple phantom that is suitable for clinical scanning, and does not require a particular phantom containing some metals or specific fine structures, as required in methods previously used for measurements of spatial resolution. Therefore, the scanned image of the phantom will be reliable and of good quality, and this is used directly as a confident reference image for the verification. When one obtains LSF, PSF or MTF values, verification using our method is recommended. Further, when another method for the measurement of LSF and PSF is developed, it could be validated using our technique, as illustrated in the method proposed by Boone [Med. Phys. 28, 356-360 (2001)] and used in this paper.

This finding provides indirect evidence for the parietal white matter involvement in OCD, thus suggesting a change in the phospholipids of myelinated axons and/or glia cells.

Certain low-molecular-weight substrate analogs act both as in vitro competitive inhibitors of lysosomal hydrolases and as intracellular enhancers (chemical chaperones) by stabilization of mutant proteins. In this study, we performed oral administration of a chaperone compound N-octyl-4-epi-beta-valienamine to G(M1)-gangliosidosis model mice expressing R201C mutant human beta-galactosidase. A newly developed neurological scoring system was used for clinical assessment. N-Octyl-4-epi-beta-valienamine was delivered rapidly to the brain, increased beta-galactosidase activity, decreased ganglioside G(M1), and prevented neurological deterioration within a few months. No adverse effect was observed during this experiment. N-Octyl-4-epi-beta-valienamine will be useful for chemical chaperone therapy of human G(M1)-gangliosidosis.