Krausz Y, Bonne O, Gorfine M, Karger H, Lerer B, Chisin R
Department of Nuclear Medicine, Hadassah University Hospital, Jerusalem, Israel.
Neuroradiology. 1998 Jul;40(7):428-34. doi: 10.1007/s002340050617.
Previous functional imaging data generally show impairment in global cerebral blood flow (CBF) with age. Conflicting data, however, concerning age-related changes in regional CBF (rCBF) have been reported. We examined the relative rCBF in a sample of healthy subjects of various ages, to define and localize any age-related CBF reduction. Twenty-seven healthy subjects (17 male, 10 female; mean age 49 +/- 15, range 26-71, median 47 years) were studied by 99mTc-HMPAO brain SPECT. The younger age group consisted of subjects below, the older group above 47 years of age, respectively. Analysis was performed by applying three preformed templates, each containing delineated regions of interest (ROIs), to three transaxial brain slices at approximately 4, 6, and 7 cm above the orbitomeatal line (OML). The average number of counts for each ROI was normalized to mean uptake of the cerebellum and of the whole brain slice. Globally, 99mTc-HMPAO uptake ratio normalized to cerebellum was significantly decreased in older subjects, affecting both hemispheres. A slight left-to-right asymmetry was observed in HMPAO uptake of the whole study group. It did not, however, change with age. Regionally, both cortical and subcortical structures of older subjects were involved: uptake ratio to cerebellum was significantly lower (after correction for multiple testing) in the left basal ganglia and in the left superior temporal, right frontal and bilateral occipital cortices at 4 cm above the OML. At 6 cm above the OML, reduced uptake ratios were identified in the left frontal and bilateral parietal areas. At 7 cm, reduced uptake was detected in the right frontal and left occipital cortices. Most of these differences were reduced when uptake was normalized to whole slice, whereas an increase in uptake ratios was observed in the cingulate cortex of the elderly. An inverse correlation between age and HMPAO uptake ratios normalized to cerebellum was observed in a number of brain regions. These findings suggest that advancing age has a differential effect on cerebral perfusion reflected in brain 99mTc-HMPAO uptake.
以往的功能成像数据通常显示，随着年龄增长，全脑血流量（CBF）会出现损害。然而，关于局部脑血流量（rCBF）与年龄相关变化的数据却相互矛盾。我们对不同年龄的健康受试者样本进行了相对rCBF检测，以确定并定位任何与年龄相关的CBF减少情况。通过99mTc-HMPAO脑单光子发射计算机断层扫描（SPECT）对27名健康受试者（17名男性，10名女性；平均年龄49±15岁，范围26 - 71岁，中位数47岁）进行了研究。较年轻年龄组由年龄低于47岁的受试者组成，较年长年龄组由年龄高于47岁的受试者组成。分析时，将三个预先形成的模板（每个模板都包含划定的感兴趣区域（ROI））应用于眶耳线（OML）上方约4厘米、6厘米和7厘米处的三个横轴位脑切片。每个ROI的平均计数被归一化为小脑和整个脑切片的平均摄取量。总体而言，年长受试者中归一化为小脑的99mTc-HMPAO摄取率显著降低，且双侧半球均受影响。在整个研究组的HMPAO摄取中观察到轻微的左右不对称。然而，这种不对称并未随年龄变化。局部来看，年长受试者的皮质和皮质下结构均受累：在OML上方4厘米处，左侧基底神经节、左侧颞上回、右侧额叶和双侧枕叶皮质中，归一化为小脑的摄取率显著降低（在进行多重检验校正后）。在OML上方6厘米处，左侧额叶和双侧顶叶区域的摄取率降低。在7厘米处，右侧额叶和左侧枕叶皮质的摄取降低。当摄取量归一化为整个切片时，这些差异大多减小，而在老年人的扣带回皮质中观察到摄取率增加。在多个脑区观察到年龄与归一化为小脑的HMPAO摄取率之间呈负相关。这些发现表明，年龄增长对脑灌注有不同影响，这在脑99mTc-HMPAO摄取中得到体现。
