Type:
Educational Exhibit
Keywords:
Neuroradiology brain, Neuroradiology peripheral nerve, Neuroradiology spine, CT, MR, Imaging sequences, Image verification
Authors:
M. Kanoto, Y. Toyoguchi, A. Oda, T. Hosoya; Yamagata/JP
DOI:
10.1594/ecr2013/C-0765
Imaging findings OR Procedure details
Image Analysis
The subjects are four cases diagnosed as adult onset AT/RT in Yamagata University Hospital from 1999 to 2010 (2 men and 2 women; mean age: 34.3 years old; range: 21–60 years old).
All cases were precisely pathologically diagnosed by biopsy,
operation or autopsy.
We retrospectively evaluated primary sites,
image findings (CT,
MRI and angiography) and survival period.
CT findings were classified into high,
iso or low density.
MRI findings were classified into high,
iso,
low or mixed intensity in each sequence (including DWI,
T1WI,
T2WI and T1WI with gadolinium contrast enhancement).
In this connection,
"mixed intensity" was defined as a heterogeneous mixture of both high and low intensity in the tumor.
Angiography findings were evaluated regarding the existent of tumor stain.
These image findings were evaluated by an experienced neuroradiologist (10 years of experience).
In Japan, if patients had not come to the hospital for five years,
we may cancel image films.
Therefore,
if the image films were cancelled,
a neuroradiologist evaluated the image findings by an imege interpretation report.
Image Findings
All image findings and clinical features are summarized in Table 1.
Tumors occurred in cervical spinal cord,
at suprasellar cistern,
at pineal region and at jugular foramen.
All tumors showed hypointensity on T1WI,
mixed intensity on T2WI and contrast enhancement.
One of two cases in which angiography was performed showed obvious tumor stain and early venous filling.
In only a case,
the AT/RT showed high density on CT,
very high intensity on diffusion weighted image (DWI) and decreasing apparent diffusion coefficient (ADC).
Case Presentation
We show three cases as follows in which the images are available.
- A case was a 60 years old male. The tumor,
so called dumbbell shape, was seen in C5-Th1 level. MRI showed low intensity on T1WI,
mixed intensity on T2WI and contrast enhancement (Fig.
1-4).
- A case was a 31 years old female.
The tumor was seen in suprasellar region.
MRI sThowed low intensity on T1WI,
mixed intensity on T2WI and well contrast enhancement (Fig.
5-7).
Tumor stain in angigraphy was not seen (Fig.
8).
- A case was a 25 years old male.
The tumor was seen in left jugular foramen.
CT showed slight high density with faint calcification and well contrast enhancement (Fig.
9,10).
MRI showed low intensity on T1WI,
mixed intensity on T2WI,
high intensity on DWI,
low intensity on ADC map and well contrast enhancement (Fig.
11-14).
Angiography in left external carotid artery showed obvious tumor stain and early venous filling in left jugular foramen. Therefore,
it was suggested that the tumor was marked hypervascularity (Fig.
15).
The follow up MRI after 1 month revealed extreamly rapid growth (Fig.
16) and the follow up CT after 7 months revealed metastasis for multiple organs (liver,
bone,
lung and so on) (Fig.
17).
Discussion
We have experienced four adult onset AT/RT cases in single institute so far.
It is quite a surprising fact.
The AT/RT is very rare,
However,
there is some possibity of occurring AT/RTs in adult cases.
Actually,
we have experienced a case of AT/RT in a 60 years old case.
AT/RTs occur in a variety of sites (spine,
suprasellar region,
pineal region and jugular foramen).
The prognosis was extreamly poor (mean survival time: 16.5 months). MRI findings on T1WI and contrast enhancement was non specific.
Mixed intensity on T2WI was seen in all cases.
On the other hand,
in one case,
there was high intensity on DWI,
decreasing ADC and hypervascularity on angiography.
It may be reflect high cellurality in the tumor.
In pediatric cases,
charasteristic image findings is also high density on CT,
calcification,
hemorrhage,
necrosis,
cystic changes,
high intensity on DWI and contrast enhancement.
It may be specific image findings in adult onset AT/RTs as well.