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41.
Abstract

To clarify the topographical relationship between peri-Rolandic lesions and the central sulcus, we carried out presurgical functional mapping by using magnetoencephalography (MEG), functional magnetic resonance imaging (f-MRI), and motor evoked potentials (MEPs) on 5 patients. The sensory cortex was identified by somatosensory evoked magnetic fields using MEG (magnetic source imaging (MSI)). The motor area of the hand region was identified using f-MRI, during a hand squeezing task. In addition, transcranial magnetic stimulation localized the hand motor area on the scalp, which was mapped onto the MRI. In all cases, the sensory cortical vein or the lack of any functional activation in the area of peri-lesional edema. MEPs were also unable to localize the entire motor strip. Therefore, at present, MSI is considered to be the most reliable method to localize peri-Rolandic lesions. [Neurol Res 1995; 17: 361-367] cortical vein or the lack of any functional activation in the area of peri-lesional edema. MEPs were also unable to localize the entire motor strip. Therefore, at present, MSI is considered to be the most reliable method to localize peri-Rolandic lesions. [Neurol Res 1995; 17: 361-367]  相似文献   
42.
We have previously reported free radical production after traumatic brain injury (TBI), which induces neural stem cell (NSC) degeneration and death. However, the effects of aging on NSC proliferation around the damaged area following TBI have not been investigated. Therefore, in this study, we used 10-week (young group) and 24-month-old (aged group) rat TBI models to investigate the effects of aging on NSC proliferation around damaged tissue using immunohistochemical and ex vivo techniques. Young and aged rats received TBI. At 1, 3 and 7 days after TBI, immunohistochemical and lipid peroxidation studies were performed. Immunohistochemistry revealed that the number of nestin-positive cells around the damaged area after TBI in the aged group decreased significantly when compared with those in the young group (P < 0.01). However, the number of 8-hydroxy-2′-deoxyguanosine-, 4-hydroxy-2-nonenal- and single-stranded DNA (ssDNA)-positive cells and the level of peroxidation around the damaged area after TBI significantly increased in the aged group, compared with those in the young group (P < 0.01). Furthermore, almost all ssDNA-positive cells in young and aged groups co-localized with NeuN and nestin staining. Ex vivo studies revealed that neurospheres, which differentiated into neurons and glia in culture, could only be isolated from injured brain tissue in young and aged groups at 3 days after TBI. These results indicate that, although there were fewer NSCs that have the potential to differentiate into neurons and glia, these NSCs escaped free radical-induced degeneration around the damaged area after TBI in the aged rat brain.  相似文献   
43.
44.

Purpose

The aim of our study was to compare the diagnostic performance of 68Ga-PSMA PET and 99mTc bone scintigraphy (BS) for the detection of bone metastases in prostate cancer (PC) patients.

Methods

One hundred twenty-six patients who received planar BS and PSMA PET within three months and without change of therapy were extracted from our database. Bone lesions were categorized into benign, metastatic, or equivocal by two experienced observers. A best valuable comparator (BVC) was defined based on BS, PET, additional imaging, and follow-up data. The cohort was further divided into clinical subgroups (primary staging, biochemical recurrence, and metastatic castration-resistant prostate cancer [mCRPC]). Additionally, subgroups of patients with less than 30 days delay between the two imaging procedures and with additional single-photon emission computed tomography (SPECT) were analyzed.

Results

A total of 75 of 126 patients were diagnosed with bone metastases. Sensitivities and specificities regarding overall bone involvement were 98.7–100 % and 88.2–100 % for PET, and 86.7–89.3 % and 60.8–96.1 % (p?<?0.001) for BS, with ranges representing results for ‘optimistic’ or ‘pessimistic’ classification of equivocal lesions. Out of 1115 examined bone regions, 410 showed metastases. Region-based analysis revealed a sensitivity and specificity of 98.8–99.0 % and 98.9–100 % for PET, and 82.4–86.6 % and 91.6–97.9 % (p?<?0.001) for BS, respectively. PSMA PET also performed better in all subgroups, except patient-based analysis in mCRPC.

Conclusion

Ga-PSMA PET outperforms planar BS for the detection of affected bone regions as well as determination of overall bone involvement in PC patients. Our results indicate that BS in patients who have received PSMA PET for staging only rarely offers additional information; however, prospective studies, including a standardized integrated x-ray computed tomography (SPECT/CT) protocol, should be performed in order to confirm the presented results.
  相似文献   
45.
Graefe's Archive for Clinical and Experimental Ophthalmology - The aim of this study was to analyze choroidal structures in healthy subjects and patients with/without diabetic macular edema...  相似文献   
46.
A less invasive transsphenoidal approach with a keyhole dural opening for intrasellar arachnoid cysts is described. This approach was used to address seven sellar cystic lesions with suprasellar extension; they were six intrasellar arachnoid cysts (IACs) and one Rathke’s cleft cyst (RCC). In all cases, preoperative MRI revealed cerebrospinal fluid (CSF) intensity on both T1- and T2-weighted images. On preoperative contrast-enhanced MRI, five of the six IACs manifested posterior displacement of the flattened pituitary gland toward the dorsum sellae; one of the six IACs and the RCC exhibited a flattened pituitary gland on the anterior surface of the cyst. Wide cyst cisternostomy through a keyhole dural opening was carried out safely using a microscope with the support of a thin angled endoscope (30° and/or 70°, diameter 2.7 mm). As we aimed to avoid iatrogenic injury of the pituitary function, we found it difficult to obtain a sufficiently wide and precise opening of the cyst wall when the pituitary gland was located on the anterior surface of the cyst wall. Our approach facilitates safe cyst cisternostomy as wide as that obtainable by transcranial manipulation. In addition, CSF leakage is prevented by dural plasty using the fascia lata and stitching with 6-0 monofilament sutures. This technique can be adapted to address various sellar cystic lesions. However, as the posterior or anterior displacement of the normal pituitary gland in the presence of IACs or RCCs, respectively, affects the width of the cyst opening, our technique is more suitable for IACs than RCCs.  相似文献   
47.
48.
A new combined test, accelerated exercise following mild hyperventilation (HV), was examined to determine whether it is effective at detecting a positive response in patients with pharmacologically-induced coronary vasospasm and near normal coronary arteries. Fifty-eight consecutive patients who underwent both triple non-invasive spasm provocation tests and diagnostic coronary angiography were enrolled. They all had pharmacologically-induced coronary vasospasms and no significant organic stenosis. In these patients, an HV test was performed first, followed by a treadmill exercise test (TET), and finally the new combined test under no medication within 3 days. Of the 58 patients, positive responses were observed in 9 patients to the HV, in 15 to the TET, and in 35 to the newly combined test. The remaining 21 patients had negative responses although the triple sequential tests were perfomed. Thus, the sensitivities of the HV test, TET, and newly combined test were 16% (9/58), 26% (15/58), and 63% (35/56), respectively. Forty-six subjects with near normal coronary arteries and no ACh-provoked spasm served as controls. None of these subjects had positive responses to any of these three tests, and thus their specificity was all 100%. No serious or irreversible complications were seen in this study. We recommend this newly-combined protocol for the induction of coronary artery spasm in patients with vasospastic angina pectoris and without significant stenosis as a diagnostic tool.  相似文献   
49.
Annals of Nuclear Medicine - This study aimed to evaluate the accuracy of six threshold-based segmentation methods with different target-to-background ratios (TBR), images with different voxel...  相似文献   
50.
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