The Navigator helps you select and examine a single slice from a whole brain.
颅脑影像数据库的资料是通过几种不同成像技术采集地，其中包括磁共振成像和放射性功能成像。在某些病例中，影像是在不同时间段采集地，目的是可以观察脑部的变化情况，并了解产生这些变化的原因是因其自身还是因药物或外科治疗而产生的。
Brain image datasets are acquired using several imaging technologies, including magnetic resonance structural imaging and radionuclide functional imaging. In some cases datasets are gathered repeatedly over a time interval, in order to see how the brain changes, either by itself or in response to drug or surgical treatment.
How is it possible to see the same part of the brain with different techniques or the same part across time? In each Whole Brain Atlas case, the datasets are carefully superposed, or shown "in register".
这样就可以通过不同成像方式及不同时间来精确地比较同一扫描平面的变化。
This permits precise comparison of data from the same slice plane taken from different image types or different time points.
Here is an example of the Navigator. The image at top is a T2-weighted MR in the transaxial plane. To learn more about what that means, check the Neuroimaging Primer, and the MR help pages. Click on the image to download a copy in the gif format. The subject's left is at right; this unfortunate convention has been widely adopted, and is used in the Atlas. The Navigator's tools appear beneath the main image, and will be described in detail below.
The location of the image in the whole brain dataset is shown as the yellow line in the
sagittal image (the side view). The buttons to the left retrieve the next or previous
image above or below the current image. The sagittal image is an "imagemap", so
the slice can be directly chosen by clicking on the sagittal image at the desired slice
location. The "cine" button retrieves a movie (MPEG). As of August 20, 1997, to
get an MPEG player, try
ftp://ftp.netcom.com/pub/cf/cfogg/mpeg2 .
If you are running Windows95 (condolences), you might want to poke around
http://www.windows95.com; last we checked, Win95 MPEG players can be found on this site at: http://www.windows95.com/apps/video.html
The list of image types available for the current case is shown at left. Abbreviations are expanded at the bottom of this help page. The time scale in this example is Days, at bottom left. The tickmark for the currently visible datset, MR-T2, is shown in yellow. The arrows at right change the image type; for example, clicking the up arrow will change the main image to a proton density image, MR-PD, and clicking the down arrow will jump to a T1-weighted MR image, MR-T1. The image dataset can also be directly selected by clicking on the tickmark. The arrows at bottom change the timepoint for, in this case, CT, which was acquired at two times separated by four days.
Here is another example of a Navigator page, taken from one of the tumor cases . This Navigator page shows two images, T2-weighted MR, Thallium SPECT, and their overlay, indicated on the timelines by yellow tickmarks. These images are taken from a case in which 3 MR, 9 Thallium SPECT, and 9 perfusion SPECT datasets are available.
注意在有些时间段上的标记中有一部分是细的，一部分是粗的。上一半是粗的标记和现在正在显示的层面共用一组重叠像。（三组影像中最左边的一幅均用细标标记，在时间段上是相应的黄色）。点击标记上细的部分可以看到与细标相关的最新数据与左侧一组数据的重叠影。点击细的一半得到的影像是没有重叠的。之后是点击中间时间线下的按钮，得到的是从上一次或下一次时间点上的影像。每一个影像都和所有的影像互相综合在一起，所以在每一个时间点上都可以看到同一个层面。
Note that some of the timeline tickmarks have a thick part and a thin part. Tickmarks with thick upper halves correspond to datasets sharing an overlay with the "current" dataset (the leftmost of the three slice images, represented on the timeline by the yellow, uniformly thin tickmark). Click on the thick part to see an overlay of the same "leftmost" image with the new dataset corresponding to that tickmark. The thin half retrieves the image type without an overlay. Again, the buttons at center, beneath the timeline, retrieve datasets from the next/previous time point. Each dataset is in registration with all others, so the same slice plane is sampled at each timepoint.
返回全脑图库 Return to the Whole Brain Atlas