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Zhang QH, Liu GT, Schlyter F, Birgersson G, Anderson P, Valeur P. Olfactory responses of Ips duplicatus from inner Mongolia, China to nonhost leaf and bark volatiles. J Chem Ecol 2001; 27:995-1009. [PMID: 11471951 DOI: 10.1023/a:1010395221953] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Leaf and bark volatiles from nonhost angiosperm trees were tested on Ips duplicatus by gas chromatographic-electroantennographic detection (GC-EAD) and by pheromone-baited traps in Sweden and Inner Mongolia, China, respectively. GC-EAD analysis of the headspace volatiles from fresh bark chips of Betula pubescens revealed trans-conophthorin, two green leaf volatiles (GLVs): 1-hexanol and (Z)-3-hexen-1-ol, and two C8 alcohols: 3-octanol and 1-octen-3-ol, that consistently elicited antennal responses by I. duplicatus. The identification of these EAD-active compounds was confirmed in further GC-EAD recordings with synthetic mixtures. Antennal responses were also found to synthetic (E)-2-hexen-1-ol and linalool, which have been identified from the leaves of nonhost birch and aspen species. No antennal responses of I. duplicatus were found to hexanal, (E)-2-hexenal, and (Z)-3-hexyl acetates. In field trapping experiments, blends of EAD-active green leaf alcohols or C8 alcohols, or transconophthorin alone resulted in significant reductions (27-60%) in the number of I. duplicatus captured compared with pheromone-baited traps. The unsuitable host compound, verbenone (Vn), also significantly reduced trap catches by up to 60% in both experiments. The strongest disruptive effect resulted from the addition of the combination of green leaf alcohols, C8 alcohols, and verbenone to the pheromone trap, which caused an 84% reduction in trap catch. The blend of two green leaf aldehydes plus the acetate increased the trap catches in 1998 and had no negative or positive effects in 1999. Our results suggest that these nonhost volatiles (NHVs) are important olfactory signals used by I. duplicatus in host selection. They may have great significance in developing semiochemical-based management programs for I. duplicatus by reducing or stopping attacks on suitable hosts.
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Balcer LJ, Liu GT, Heller G, Bilaniuk L, Volpe NJ, Galetta SL, Molloy PT, Phillips PC, Janss AJ, Vaughn S, Maguire MG. Visual loss in children with neurofibromatosis type 1 and optic pathway gliomas: relation to tumor location by magnetic resonance imaging. Am J Ophthalmol 2001; 131:442-5. [PMID: 11292406 DOI: 10.1016/s0002-9394(00)00852-7] [Citation(s) in RCA: 151] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To examine the potential for visual acuity loss, and its relation to extent and location of optic pathway gliomas in a cohort of children with neurofibromatosis type 1 studied with magnetic resonance imaging. METHODS We reviewed the neuro-ophthalmologic records and brain/orbital magnetic resonance imaging scans for 43 consecutive pediatric patients with neurofibromatosis type 1 and optic pathway gliomas who were followed at the Children's Hospital of Philadelphia. The presence of visual loss, defined as abnormal visual acuity for age in one or both eyes, was determined. Optic pathway gliomas were classified by tumor extent and location according to involvement of the optic nerves, chiasm, and postchiasmal structures by magnetic resonance imaging. RESULTS Involvement of the optic tracts and other postchiasmal structures at tumor diagnosis was associated with a significantly higher probability of visual acuity loss (P =.048, chi-square test). Visual loss was noted in 20 of 43 patients (47%) at a median age of 4 years; however, three patients developed visual acuity loss for the first time during adolescence. CONCLUSIONS In pediatric patients with neurofibromatosis type 1 and optic pathway gliomas, the likelihood of visual loss is dependent on the extent and location of the tumor by magnetic resonance imaging and is particularly associated with involvement of postchiasmal structures. Furthermore, older age during childhood (adolescence) does not preclude the occurrence of visual loss. Close follow-up beyond the early childhood years, particularly for those with postchiasmal tumor, is recommended.
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Hinkle DA, Raizen DM, McGarvey ML, Liu GT. Cerebral air embolism complicating cardiac ablation procedures. Neurology 2001; 56:792-4. [PMID: 11274320 DOI: 10.1212/wnl.56.6.792] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Two patients with similar courses of neurologic impairment and subsequent recovery after cerebral air embolism complicating cardiac ablation procedures are described. Hyperbaric oxygen therapy, combined with aggressive resuscitative efforts, appears to have contributed to each patient's recovery.
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Kim W, Clancy RR, Liu GT. Horner syndrome associated with implantation of a vagus nerve stimulator. Am J Ophthalmol 2001; 131:383-4. [PMID: 11239877 DOI: 10.1016/s0002-9394(00)00782-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE To report a case of Horner syndrome that occurred after implantation of a vagus nerve stimulator. METHODS Case report. RESULTS A 6-year-old female with cerebral dysgenesis and intractable partial seizures presented with Horner syndrome after vagus nerve stimulator implantation. CONCLUSION Horner syndrome can occur as a result of the vagus nerve stimulator implant procedure and should be included as one of its possible surgical complications.
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Liu GT, Galetta SL. The neuro-ophthalmologic examination (including coma). OPHTHALMOLOGY CLINICS OF NORTH AMERICA 2001; 14:23-39, vii. [PMID: 11370569] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
Ophthalmologic practice requires a solid foundation in the principles and interpretation of the neuro-ophthalmologic examination. This article reviews the techniques used in the neuro-ophthalmologic examination to assess visual acuity, ocular motility, visual fields, the pupils, the eyelids, and the fundus. The neuro-ophthalmological examination in comatose patients is also reviewed. Neuro-ophthalmic techniques are paramount in the assessment of comatose patients, especially with regard to brainstem localization and diagnosis.
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Miki A, Liu GT, Englander SA, Raz J, van Erp TG, Modestino EJ, Liu CJ, Haselgrove JC. Reproducibility of visual activation during checkerboard stimulation in functional magnetic resonance imaging at 4 Tesla. Jpn J Ophthalmol 2001; 45:151-5. [PMID: 11313046 DOI: 10.1016/s0021-5155(00)00352-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
PURPOSE To investigate the reproducibility of visual activation by checkerboard stimulation, we used functional magnetic resonance imaging (fMRI) at 4 Tesla (T). METHODS Four subjects were studied with fMRI at 4 T during checkerboard visual stimulation. The functional images were realigned and spatially normalized to the standard brain. For each subject, statistical parametric maps were made for each study, and the reproducibility was determined based on the number of supra-threshold voxels (Z > 3.5, 4.5, and 5.5). RESULTS The mean ratio for the number of supra-threshold (Z > 4.5) voxels was 0.75, and the mean ratio for the overlapping voxels was 0.61. Restricting the region of interest within the posterior half of the brain improved reproducibility values at the low threshold (Z > 3.5), but did not improve the values at the higher thresholds. CONCLUSIONS Despite the fact that more than half of the supra-threshold voxels were found to be active for the repeated scans, visual activation with checkerboard stimulation seems to be less reproducible than that by flash stimulation.
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Miki A, Liu GT, Fletcher DW, Hunter JV, Haselgrove JC. Ocular dominance in anterior visual cortex in a child demonstrated by the use of fMRI. Pediatr Neurol 2001; 24:232-4. [PMID: 11301228 DOI: 10.1016/s0887-8994(00)00260-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Negative signal changes in the visual cortex have been observed during visual stimulation when performing functional magnetic resonance imaging (fMRI) in children. This report investigated whether the ocular dominance, which has been demonstrated in the contralateral anterior visual cortex in adults, could be observed in a child by the use of fMRI. A 5-year-old child was studied using fMRI at 1.5 T during alternating monocular visual stimulation under sedation with morphine and pentobarbital. The functional images were motion corrected, and statistical parametric maps were made by contrasting the left or right eye stimulation conditions vs the right or left eye stimulation conditions, respectively, at each voxel. Areas with negative signal changes were found on the left anterior visual cortex during monocular visual stimulation of the right eye and vice versa. There was no area with negative or positive signal change on the ipsilateral visual cortex to the stimulated eye and no area with positive signal change on the contralateral visual cortex. Contralateral ocular dominance of anterior visual cortex similar to that of adults was demonstrated in this child with a negative correlation with the visual stimulus. This finding suggests that peripheral visual fields are represented in the anterior visual cortex of 5-year-old children.
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Miki A, Liu GT, Raz J, Englander SA, Bonhomme GR, Aleman DO, Modestino EJ, Liu CS, Haselgrove JC. Visual activation in functional magnetic resonance imaging at very high field (4 Tesla). J Neuroophthalmol 2001; 21:8-11. [PMID: 11315986 DOI: 10.1097/00041327-200103000-00002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Functional magnetic resonance imaging (fMRI) at very high field strengths provides functional brain mapping with the enhanced signal to noise ratio and the larger blood oxygenation level-dependent (BOLD) effect. We report activated areas in the standard space detected by fMRI at 4 Tesla (T) during simple visual stimulation. MATERIALS AND METHODS Twelve healthy young subjects were scanned using a 4 T scanner during binocular flashing visual stimulation. Functional images were realigned to the first scan and then spatially normalized. Individual and group data analyses were performed to identify areas of visual activation. RESULTS Activation of the bilateral primary visual cortex (V1/V2) was observed along the entire calcarine fissure in all subjects. The activated area extended to the extrastriate cortex in all subjects. Activation of the bilateral lateral geniculate nucleus (LGN) was detected in all subjects. The group data showed activation of the bilateral primary visual cortex and the bilateral lateral geniculate nucleus. CONCLUSIONS Robust activation of the vision-related areas was successfully obtained in all subjects using a 4 T magnetic resonance scanner. These results suggest that fMRI at very high field strengths may be effective in showing visual system physiology, and that it can be a promising method to assess visual function of human subjects.
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Shin RK, Stern JW, Janss AJ, Hunter JV, Liu GT. Reversible posterior leukoencephalopathy during the treatment of acute lymphoblastic leukemia. Neurology 2001; 56:388-91. [PMID: 11171907 DOI: 10.1212/wnl.56.3.388] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Three children with acute lymphoblastic leukemia developed altered mental status, headaches, seizures, and visual changes associated with reversible posterior cerebral changes on MRI. These clinical and radiologic findings were consistent with the reversible posterior leukoencephalopathy syndrome, which has not been widely recognized in this setting.
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Abstract
The clinical characteristics, differential diagnosis, and treatment options are presented for five different categories of neuro-ophthalmic disease. Nystagmus, optic neuritis, diplopia, pseudotumor cerebri, and temporal arteritis, are frequently encountered in neuro-ophthalmic practice. This article focuses on current therapies for these neuro-ophthalmic disorders. Potential differences in approach to pediatric versus adult patients are emphasized.
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Liang RQ, Zhang YR, Liu SB, Li BY, Gu D, Tang ZH, Liu GT. [Application of molecular markers-assisted selection of wx genes in breeding the waxy wheat]. YI CHUAN XUE BAO = ACTA GENETICA SINICA 2001; 28:856-63. [PMID: 11582746] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 04/17/2023]
Abstract
Chinese Spring and its null-tetrasomic lines were used to identify the specific bands of STS-marker and microsatellites (SSR) marker of wx genes. Twelve varieties and five waxy wheat lines were screened with these two markers, and the results are in agreement with those from Wx subunits SDS-PAGE. A F2 segregating population from cross Jiangsu Baihuomai x Kanto 107 was also detected by molecular markers, not only eight wx genotypes were developed while three genotypes did not exist in the nature, but also the first batch of waxy wheat lines were bred. The Jiangsu Bainuomai improvement population was screened, and six 7D momosomic plants with wx-D1b were obtained, which could provide materials for waxy wheat breeding. Application molecular markers of wx genes will improve the selection procedure for the waxy wheat and good noodle-quality wheat.
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Liu GT. [Discussion on the modernization of Chinese herbal medicine]. ZHONGGUO ZHONG XI YI JIE HE ZA ZHI ZHONGGUO ZHONGXIYI JIEHE ZAZHI = CHINESE JOURNAL OF INTEGRATED TRADITIONAL AND WESTERN MEDICINE 2001; 21:3-4. [PMID: 12577365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
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Dlugos DJ, Liu GT. Subacute sclerosing panencephalitis in an American-born adult. Clin Infect Dis 2001; 32:173-4. [PMID: 11112670 DOI: 10.1086/317531] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2000] [Revised: 05/31/2000] [Indexed: 11/03/2022] Open
Abstract
We describe a case of an adult born in the United States who had subacute sclerosing panencephalitis (SSPE). We discuss the possibility that the patient contracted subclinical measles during the 1989-1991 measles epidemic in the United States.
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Miki A, Raz J, Englander SA, Butler NS, van Erp TG, Haselgrove JC, Liu GT. Reproducibility of visual activation in functional magnetic resonance imaging at very high field strength (4 Tesla). Jpn J Ophthalmol 2001; 45:1-4. [PMID: 11163039 DOI: 10.1016/s0021-5155(00)00304-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE The reproducibility of functional magnetic resonance imaging (fMRI) has been studied on 1.5 Tesla (T) (high field strength) scanners. We report the reproducibility of visual activation in fMRI at 4 T (very high field strength). METHODS Five healthy subjects were scanned twice in the same session with a 4 T scanner during binocular flashing visual stimulation. The activated areas during the first and second acquisition were compared. RESULTS Activation of the visual cortex was observed in all subjects and activation of lateral geniculate nucleus was also detected in four subjects. The ratio of overlapping activated voxels in the first and second acquisition was 0.81 +/- 0.05. CONCLUSIONS Reproducibility of visual activation using fMRI at 4 T was found to be acceptable, and the results from 4T scanners show a reliability similar to those at 1.5 T.
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Miki A, Raz J, Haselgrove JC, van Erp TG, Liu CS, Liu GT. Functional magnetic resonance imaging of lateral geniculate nucleus at 1.5 tesla. J Neuroophthalmol 2000; 20:285-7. [PMID: 11130759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Although activation of the lateral geniculate nucleus has been detected by functional magnetic resonance imaging with magnetic field strengths higher than 2.0 Tesla, there have been no reports of functional magnetic resonance imaging of the lateral geniculate nucleus with the more widely available 1.5 Tesla scanner. The authors used functional magnetic resonance imaging techniques at 1.5 Tesla to detect lateral geniculate nucleus activation in five of seven healthy subjects. This study shows that visual activation of the lateral geniculate nucleus can be obtained with functional magnetic resonance imaging using conventional 1.5 Tesla scanners.
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Yang JB, Li XW, Dong WH, Kong TH, Song HX, Zheng XY, Liu GT. [Effect of anticancer polypeptide from Buthus Martensii venom on immune function in the H22-bearing mice]. ZHONGGUO ZHONG YAO ZA ZHI = ZHONGGUO ZHONGYAO ZAZHI = CHINA JOURNAL OF CHINESE MATERIA MEDICA 2000; 25:736-9. [PMID: 12525062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/28/2023]
Abstract
OBJECTIVE To observe the effect of anticancer polypeptide from Buthus Martensii Venom (APBMV) on Immune function in the H22-bearing mice. METHODS The MTT colorimetric method, homolysin assay, lymphocyte transformation test, delayed hypersensitivity assay and WBC-count of peripheral blood were used in this study. RESULTS APBMV could obviously augment NK activity, promote proliferation of lymphocytes induced by Con A, potentiate the response of DTH induced by DNCB, antagonize the decrease of WBC in peripheral blood induced by 5-Fu in the H22-bearing mice. CONCLUSION APBMV can obviously increase immune function in the H22-bearing mice and antagonize hypoimmunity immunodeficiency or immunodeficiency induced by chemotherapy or the tumor.
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Miki A, Liu GT, Raz J, van Erp TG, Liu CJ, Leuthardt EC, Haselgrove JC. Contralateral monocular dominance in anterior visual cortex confirmed by functional magnetic resonance imaging. Am J Ophthalmol 2000; 130:821-4. [PMID: 11124303 DOI: 10.1016/s0002-9394(00)00577-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
PURPOSE Although it is known that the damage to anterior striate cortex results in temporal peripheral visual field loss of the contralateral eye in patients with cerebral visual disturbance, the monocularity of anterior striate cortex has not been demonstrated in normal living humans. The aim of this study was to investigate whether this could be shown noninvasively using functional magnetic resonance imaging of the human visual cortex. METHODS Eleven normal volunteers were studied with functional magnetic resonance imaging during alternating monocular visual stimulation using a 1.5 Tesla scanner. The data were motion corrected and spatially normalized to the standard brain. The monocular activation of the visual cortex was compared with the activation by the other eye. RESULTS In the individual data analysis, contralateral eye dominance was always observed in the anterior striate cortex. In the group analysis from 11 subjects, the area with contralateral eye dominance was found in the most anterior part of primary visual cortex where the calcarine fissure merged with the parieto-occipital sulcus. CONCLUSIONS This study shows that the contralateral eye dominance of anterior striate cortex can be detected noninvasively with functional magnetic resonance imaging during monocular visual stimulation. The finding confirms that the anterior striate cortex, where the monocular temporal crescent is represented, is primarily monocular, but the fact that greatest density of retinal ganglion cells and photoreceptors is in the nasal hemiretina must also be taken into account when interpreting these results.
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Hollander DA, Volpe NJ, Moster ML, Liu GT, Balcer LJ, Judy KD, Galetta SL. Use of a portable head mounted perimetry system to assess bedside visual fields. Br J Ophthalmol 2000; 84:1185-90. [PMID: 11004108 PMCID: PMC1723249 DOI: 10.1136/bjo.84.10.1185] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AIM This study was designed to test the ability of a portable computer driven, head mounted visual field testing system to perform automated perimetry on patients at their bedside and to compare these results with the "gold standard" for bedside examinations, confrontation visual fields. METHODS The Kasha visual field system is a portable automated perimeter which utilises a virtual reality headset. 37 neurosurgery patients were examined at their bedside with a central 24 degree suprathreshold testing strategy after confrontation visual field testing. The patterns of visual field defects were categorised and compared with the results of confrontation testing. RESULTS A total of 42 field examinations were completed on 37 patients, and the average testing time for both eyes was 4.8 minutes with the perimetry system. Each of the 11 fields (100%) classified with defects on confrontation testing was similarly categorised on head mounted perimetry. 26 out of 31 (84%) visual fields were normal on both confrontation and perimetry testing, while five out of the 31 fields (16%) which were full on confrontation had visual field defects identified by head mounted perimetry. CONCLUSION The head mounted, automated perimetry system proved easily portable and convenient for examining neurosurgical patients at their bedside in the perioperative period. The device demonstrated equal sensitivity to confrontation visual field testing methods in detecting field defects and offers the advantage of standardised, quantifiable testing with graphic results for follow up examinations.
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Lavin PJ, Donahue SP, Jacobson DM, Moster ML, Galetta SL, Liu GT, Eggenberger ER. Isolated trochlear nerve palsy in patients with multiple sclerosis. Neurology 2000; 55:321-2. [PMID: 10908924 DOI: 10.1212/wnl.55.2.321-a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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Pelak VS, Bolinger L, Galetta SL, Butler N, Stein A, Liu GT. 4.0 Tesla magnetic resonance imaging of brainstem lesions with ocular motility deficits. J Neuroophthalmol 2000; 20:135-7. [PMID: 10870931 DOI: 10.1097/00041327-200020020-00016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The authors studied six patients with brainstem ocular motility deficits with 4.0 Tesla (T) magnetic resonance imaging to investigate whether a higher field strength would produce superior images compared with 1.5T. In four patients whose lesions were evident on 1.5T, the increased signal-to-noise achieved with 4.0T allowed for better resolution at 1-mm slice thickness than was achieved at the standard 5-mm slice thickness with 1.5T. In the two patients with unremarkable 1.5T scan results, 4.0T also failed to demonstrate a lesion. Therefore, 4.0T imaging has superior resolution to 1.5T imaging and can provide more detailed images of lesions identified by 1.5T.
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Miki A, Raz J, van Erp TG, Liu CS, Haselgrove JC, Liu GT. Reproducibility of visual activation in functional MR imaging and effects of postprocessing. AJNR Am J Neuroradiol 2000; 21:910-5. [PMID: 10815667 PMCID: PMC7976737] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
BACKGROUND AND PURPOSE Functional MR imaging studies of the brain should be interpreted in the context of their reproducibility. We assessed the reproducibility of visual activation measured by functional MR imaging and analyzed the effect of image transformation to standard space. METHODS Seven healthy volunteers were studied twice with echo-planner functional MR imaging at 1.5 T during visual stimulation. The studies were separated by an interval of 2 to 7 days. Functional images were analyzed after spatial normalization to the space described by Talairach and Tournoux and/or after coregistration of the images of the second study with the images of the first study. The number of active voxels for each study was determined at three thresholds. In addition, the change in the center of the mass of activation, the mean change in signal intensity, and the mean t value within the activated area were measured. These reproducibility indexes were calculated for the spatially normalized and nonnormalized data for each subject. RESULTS Variations in visual activation were observed between the two studies in the same individual as well as across subjects. There was no evidence of an effect from image transformation on reproducibility on any of the measures. CONCLUSION Our findings show that the reproducibility of activation in functional MR imaging may be much more variable across subjects than suggested in previous studies. The use of different types of image transformation (coregistration, spatial normalization) does not significantly affect the reproducibility of visual activation.
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Volpe NJ, Sharma MC, Galetta SL, Langer DJ, Liu GT, Hurst RW, Flamm ES. Orbital drainage from cerebral arteriovenous malformations. Neurosurgery 2000; 46:820-4. [PMID: 10764254 DOI: 10.1097/00006123-200004000-00010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVE To describe the neuro-ophthalmic findings in patients with orbital drainage from cerebral arteriovenous malformations (AVMs). METHODS We reviewed the records of 100 consecutive adult patients with cerebral AVMs who presented to our institution during a 4-year period. All patients with orbital drainage were identified, and their neuro-ophthalmic evaluations were reviewed. RESULTS Three patients (3%) were identified with orbital drainage from a cerebral AVM. The first patient presented with typical chiasmal syndrome (reduced visual acuity, bitemporal hemianopia, and optic atrophy). Magnetic resonance imaging demonstrated a large left temporal and parietal lobe AVM with compression of the chiasm between a large pituitary gland and a markedly enlarged carotid artery. The second patient presented with headaches and postural monocular transient visual obscurations. Examination revealed normal visual function with minimal orbital congestion and asymmetrical disc edema, which was worse in the left eye. Magnetic resonance imaging revealed a large right parietal and occipital lobe AVM without mass effect or hemorrhage and an enlarged left superior ophthalmic vein. The third patient had no visual symptoms and a normal neuro-ophthalmic examination; a right parietal lobe AVM was discovered during an examination for the cause of headaches. CONCLUSION Orbital drainage from cerebral AVMs is rare. Manifestations may include anterior visual pathway compression, dilated conjunctival veins, orbital congestion, and asymmetrical disc swelling.
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Liu GT, Hunter J, Miki A, Fletcher DW, Brown L, Haselgrove JC. Functional MRI in children with congenital structural abnormalities of the occipital cortex. Neuropediatrics 2000; 31:13-5. [PMID: 10774990 DOI: 10.1055/s-2000-15291] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Functional MRI techniques were used to map the position of visual cortex in an awake and a sedated child with congenital anomalies of the posterior hemispheres. In one subject with cortical heterotopia, an activated cortex was found distinct from the structurally abnormal area detected on conventional MRI. In a sedated patient with holoprosencephaly, activated cortical areas in the posterior-medial portions of the hemispheres were identified. This study demonstrates the utility of functional MRI in such patients, both awake and sedated.
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Chen LH, Wang XW, Zhang WJ, Zhang XD, Hu DF, Liu GT. [Transformation of common wheat (Triticum aestivum L.) with herbicide-resistant EPSPs gene]. YI CHUAN XUE BAO = ACTA GENETICA SINICA 1999; 26:239-43. [PMID: 10589163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
The herbicide-resistant EPSPs (5-enolpyruvylshikimate-3-phosphate synthase) gene was transformed into about 1,000 young spikes and 800 young embryos of wheat variety, Jinghua 1, with gene gun. Thirty-eight and four regenerated plants were obtained respectively screened with glyphosate. All regenerated plants were analysed by PCR and/or Southern blotting. The results indicated that EPSPs gene was integrated stably into the genome of Jinghua 1, and some of the transformants showed fertile. So herbicide-resistant EPSPs gene could be used as selective marker in the transformation of monocotyledon cereal crops, such as wheat.
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Abstract
PURPOSE To describe the clinical and radiological findings in a patient with diplopia and orbital emphysema following thoracotomy. METHODS Reported is a 71-year-old woman who presented with diplopia several days following thoracotomy. RESULTS Physical examination revealed diffuse subcutaneous emphysema and a right hypertropia. Head computed tomography revealed facial and palpebral subcutaneous emphysema extending into the infratemporal fossa and orbits bilaterally. A chest tube was replaced and her diplopia resolved. CONCLUSIONS Subcutaneous emphysema can lead to diplopia and orbital emphysema in the absence of orbital trauma. Contrary to previously suggested mechanisms of orbital emphysema associated with subcutaneous emphysema, computed tomography imaging suggested that air entry into the orbit in this case was through the inferior orbital fissure.
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