We present techniques of automatic nonlinear transformation of MR images (2D or 3D). A neural network automatically finds the corresponding parts between the subject's brain images and the standard images. By iterative operations, the network generates a set of image-shifting vectors to realize a plastic transformation. For precise matching, a set of markers can be placed manually before starting the transformation on landmarks of the images, e.g., on the anterior-posterior commissural line and on the central sulcus.

Brain Mapping↗

PubMedDate not supplied

Ocular findings of Williams' syndrome.

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Aortic Valve Stenosis↗

PubMedDate not supplied

Cerebral hemiatrophy in systemic lupus erythematosus: report of a case.

An 18-year-old woman with systemic lupus erythematosus developed neuropsychiatric disorders, including aseptic meningoencephalitis, organic brain syndrome and seizure. A series of computed axial tomography scans revealed the progression of marked atrophy of the right cerebral hemisphere for a period of 3 years without occlusion or stenosis of large vessels on cerebral angiography. I-123 IMP single photon emission computed tomography disclosed a markedly decreased uptake of I-123 IMP in the right cerebral hemisphere, and also in the left cerebellar hemisphere (crossed cerebellar diaschisis), which disappeared within 2 years.

Adolescent↗

PubMedDate not supplied

Eosinophil active cytokines and surface analysis of eosinophils in Churg-Strauss syndrome.

There are few reports regarding the measurement of cytokines and surface analysis of eosinophils in Churg-Strauss syndrome (CSS). To examine the pathophysiology of CSS, concentrations of cytokines in serum and bronchoalveolar lavage fluid (BALF), and surface antigens on peripheral blood eosinophils were analyzed in five patients with CSS. Concentrations of cytokines (interleukin-1 beta (IL-1 beta), tumor necrosis factor-alpha (TNF-alpha), interleukin-3 (IL-3), interleukin-5 (IL-5) and granulocyte/macrophage colony stimulating factor (GM-CSF) were measured using ELISA. Surface antigens on eosinophils in peripheral blood were analyzed using flow cytometry. A concentration of interleukin-5 (IL-5) and TNF-alpha in serum was detected in five cases; however IL-1 beta, GM-CSF, and IL-3 were detected in 3 of 5, 2 of 5, and 1 of 5 patients, respectively. In BALF, TNF-alpha and IL-5 were detected in 2 of 3 and 1 of 3 patients, respectively; however, neither IL-1 beta, GM-CSF, nor IL-3 was detected in any. Newly expressed surface antigens such as CD25, CD4, and CD69 were observed on peripheral blood eosinophils in five cases. CD54 and HLA-DR were expressed in 4 of 5 and 3 of 5 patients, respectively. Eosinophils in peripheral blood are activated to various degrees, possibly depending on cytokine stimulation. This eosinophil activation may be related to the clinical stage of CSS.

Adult↗

PubMedDate not supplied

Quantitation of cerebral blood volume by 99mTc-DTPA-HSA SPECT.

The characteristics of technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA) as an agent for quantitation of cerebral blood volume (CBV) were examined. The radioactivity after decay correction as a percentage of the activity at 10 minutes was 84.3 +/- 1.3% at 120 minutes after the injection of 99mTc-DTPA-HSA. Radioactivity was found exclusively in plasma, with little in blood cells. The blood retention of 99mTc-DTPA-HSA is sufficient, and its use in the quantitation of CBV omits the need for centrifugation of the blood sample. CBV quantified using the tracer and a SPECT system with a single-head rotating gamma camera was 4.09 +/- 0.60 ml/100 g brain, similar to values reported previously. Two serial SPECT scans provided similar images, and the CBV values determined by the two scans were closely correlated (p < 0.001). The high reproducibility suggests that the method may be used to monitor the cerebrovascular response to drugs. It was concluded that 99mTc-DTPA-HSA has useful properties for quantitative CBV measurement and that quantitation of CBV by 99mTc-DTPA-HSA SPECT is feasible using a system with a single-head rotating gamma camera.

Adult↗

PubMedDate not supplied

A new method for monitoring the cerebrovascular response to acetazolamide using 99mTc-DTPA-HSA.

We developed a new method for monitoring the cerebrovascular response to acetazolamide using technetium-99m diethylenetriaminepentaacetic acid human serum albumin (99mTc-DTPA-HSA). We infused 740 M Bq (20 mCi) of 99mTc-DTPA-HSA intravenously and carried out dynamic scanning of the anterior view of the head for 50 minutes. Ten minutes after the start of scanning, 1,000 mg of acetazolamide was injected intravenously. In three normal volunteers, the radioactivity in brain increased for an average of 8 minutes after the injection of acetazolamide and then remained relatively stable. The average of dilatation index [(peak count/the count just before acetazolamide injection-1)x 100] was 16.1. Our method enabled us to observe vasodilation caused by acetazolamide straight, and may be of value in assessing cerebral perfusion reserve easily and quantitatively.

Acetazolamide↗

PubMedDate not supplied

Functional brain studies with H2(15)O-PET: strategies and problems for approaching higher brain functions with H2(15)O-PET.

Activation study using H2(15)O and PET is promising as a noninvasive approach to higher brain functions in humans. However before reaching a more complex paradigm, many fundamental problems need to be solved. In this study, we investigated the following issues: (1) reproducibility of regional cerebral blood flow in the resting state as measured by this method, (2) effect of physiological stimulation on cerebral blood flow, and (3) identification of activated areas on anatomical structures. Our data suggest that relative CBF images and their paired subtraction are more suitable for tapping functional localization. Changes in rCBF in the association cortex for more complicated tasks are, in general, smaller than those in the primary cortex. Combined display of PET images with three-dimensional reconstructed brain surface MR images was the most reliable technique for anatomical identification of the activated site.

Acoustic Stimulation↗

PubMedDate not supplied

Effect of cervical spinal cord stimulation (cSCS) on cerebral glucose metabolism and blood flow in a vegetative patient assessed by positron emission tomography (PET) and single photon emission computed tomography (SPECT).

This paper presents, for the first time, assessments of cerebral glucose metabolism and cerebral blood flow before and after cervical spinal cord stimulation (cSCS) in a vegetative patient. Regional cerebral metabolic rates for glucose (rCMRglc) were measured with positron emission tomography and 18F-fluoro-2-deoxy-D-glucose. Regional cerebral blood flow (rCBF) was determined with single photon emission computed tomography and N-isopropyl p-123I-iodoamphetamine. Global CMRglc in the patient was less than one-third of that in normal control subjects. An increase in rCMRglc after one week of cSCS was observed in the cerebral cortex, predominantly on the right side, where the baseline level of rCMRglc before cSCS was more severely depressed. The pattern of increase in rCBF was almost the same as that in rCMRglc. The results suggest that cSCS activates glucose metabolism and that this is followed by an increase in cerebral blood flow.

Amphetamines↗

PubMedDate not supplied

A new method for brain functional study using Tc-99m HMPAO SPECT.

The distribution of 99mTc-HMPAO in brain is in proportion to regional cerebral blood flow (rCBF) and can be interpreted as functional mapping. To evaluate local changes in CBF during neuropsychological testing, we developed a new subtraction method using HMPAO and SPECT. With patients resting, 15 mCi of HMPAO was injected and the first acquisition was performed, lasting a total of 10 minutes. Soon after the end of the first scan, patients were requested to undergo Buschke's memory test or to repeat words or numbers (repetition test). During the task, an additional 15 mCi of HMPAO was injected using the same position as in the first scan, and a second acquisition was started. A functional image was made by subtracting the image in the first scan from that in the second. In two patients with transient global amnesia and two normal controls, Buschke's memory test was performed in combination with SPECT. A Relative increase in activity was seen in the thalamus, subthalamic area, hippocampus, and some cortical areas, apparently reflecting local functional change induced by the memory task. In two patients with moderate Alzheimer's disease with severe memory loss, no increase was detected in these areas. In one patient with aphasia, the repetition test with SPECT was correlated with the WADA test and dichotic listening test, and good agreement was obtained. In conclusion, our new SPECT technique is useful in detecting alterations in rCBF during mental activity and can be applied to neurophysiological studies.

Alzheimer Disease↗

PubMedDate not supplied

Absorption of topical disodium cromoglycate and its preservatives by soft contact lenses.

Disodium cromoglycate (2%) (DSCG) was administered four times daily for one month to 10 patients using extended wear contact lenses. The same regimen was also followed for five days by 25 patients using daily wear soft contact lenses. The contact lenses and their soaking solutions were collected at the end of the wearing period and analyzed for DSCG, benzalkonium chloride (BAK), 2-phenylethanol, and EDTA. The lens soaking solutions and eluates prepared from the lenses were tested. In the extended wear group, small amounts of DSCG were detected in both the eluates and the soaking solutions. In the daily wear group DSCG was detected in small amounts in the soaking solutions but not in the eluates. BAK, EDTA, and 2-phenylethanol were not detected in any of the eluates or soaking solutions. During the study, no side effects of DSCG were observed in any of the patients. In animal experiments, radioactive DSCG was applied once to a series of rabbit eyes. Four hours after administration of the labelled DSCG, the animals' tears, cornea, and aqueous humor were examined for DSCG. Of the instilled dose, approximately 0.2% was found in the cornea, and less than 0.04% was found in the aqueous humor. We conclude that commercial DSCG applied topically to contact lenses does not result in the accumulation of either the drug or its preservatives in lenses and that DSCG can be safely applied directly onto a worn contact lens.

Animals↗