Abstract:
:Quantitative 1H MRS to determine cerebral metabolite patterns and MRI to determine CSF flow were applied to 12 patients with ventricular dilation-Group A, cortical atrophy (N = 5); or Group B, hydrocephalus (N = 7)- and in 9 normal controls. While mean brain water (Group A = 80% +/- 6; Group B = 86% +/- 5; normal = 85% +/- 4) did not differ between the two groups of patients and controls, 1H MRS distinguished those patients with cortical atrophy (Group A) (N-acetylaspartate/ creatine (NAA/Cr) = 0.69 +/- 0.17, versus normal = 1.06 +/- 0.16; P < 0.002; [NAA] = 5.9 +/- 1.3 mmoles/kg, versus normal 8.0 +/- 1.4; P < 0.02) from those with hydrocephalus (Group B) (NAA/Cr = 1.16 +/- 0.11; [NAA] = 9.2 +/- 1.2; P > 0.13 and P > 0.07). Lactate levels were elevated in 3/5 patients with cortical atrophy, but in 0/7 of those with hydrocephalus. Mean absolute concentrations (mmoles/kg) of the five major cerebral osmolytes were 41 +/- 4 (Group A), 43 +/- 6 (Group B), and 42 +/- 4 (normal), so that despite massive brain deformation, constant osmolality was maintained. 1H MRS may directly benefit surgical planning in hydrocephalus infants by clearly identifying those with cortical atrophy who do not require CSF diversion. Thinning of the cortical mantle in hydrocephalus may result from osmotically driven reduction in individual cell volumes, (shrinkage), rather than brain-compression.
journal_name
Magn Reson Medjournal_title
Magnetic resonance in medicineauthors
Bluml S,McComb JG,Ross BDdoi
10.1002/mrm.1910370317subject
Has Abstractpub_date
1997-03-01 00:00:00pages
395-403issue
3eissn
0740-3194issn
1522-2594journal_volume
37pub_type
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更新日期:2003-06-01 00:00:00
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更新日期:2012-06-01 00:00:00
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更新日期:2010-06-01 00:00:00
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更新日期:2018-07-01 00:00:00
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更新日期:2018-03-01 00:00:00
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