| |  |
| Archives
for the week: May 1 - 7 2001 | |
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| Author: | Giuseppe
Brancatelli | | Title: | CT
Findings with Emphasis on Multiphasic Helical CT in 78 Patient |
| Source: | Radiology
2001 219: 61-68 | | Review:
| The
article is a definitive article on 78 patients with 124 FNH tumors. They have
described a whole bunch of signs with respect ot FNH. A classic FNH is subcapsular,
ill-defined, with a smooth margin and shows marked homogeneous enhancement on
the arterial phase study. A central scar is seen in larger lesions. Atypical but
known features include lobulation, exophytic appearance, peritumoral vessels and
pseudocapsule.
Differenital diagnoses include hemangioma, adenoma, fibrolamellar
HCC, conventional HCC and hypervascular metastases, but differentiation is usually
not difficult. | | Additional
comment: | In
the last two years, there have been other similar definitive articles on adenoma,
hemangioma, etc. which I will try and review in the next few days. |
| | | Click
here for abstract |
| Author: | Rüdiger
von Kummer,et al | | Title: | Early
Prediction of Irreversible Brain Damage after Ischemic Stroke at CT |
| Source: | Radiology
2001 219: 95-100 | | Review:
| This
is a spin-off from the data of ECASSII, a trial conducted to assess the utility
of rTPA in early stroke.They have shown that whenever even a subtle hypodensity
is seen on a CT in an arterial territory within six hours of a stroke, it predicts
irreversible brain damage in that region. The reason this occurs is because an
ischemic area attracts water and water results in reduced parenchymal density.
The positive predictive value for this sign was 96%, which means that if a parenchymal
hypodensity is present, it is 96% definite that there is irreversible brain damage.
The negative predictive value was only 27%, which means that if there is no hypodensity,
only 27% of patients will not have irreversible brain damage. This is expected
considering the low sensitivity of CT to ischemic brain damage.
This essentially
means that all our subtle signs of infarct (insular ribbon sign, hypodense lentiform
nucleus sign) mean that the patient already has irreversible brain damage.
This of course does not translate into what it means for patient who are to go
on rTPA and no conclusions have been drawn regarding that issue. |
| | | Click
here for abstract |
| Author: | Kejal
Kantarci et al | | Title: | Mild
Cognitive Impairment and Alzheimer Disease: Regional Diffusivity of Water |
| Source: | Radiology
2001 219: 101-107 | | Review:
| This
article is a landmark article by Kantarci K et al from the Mayo Clinic. The article
shows how hippocampal apparent diffusion coefficient (ADC) is higher in patients
with Alzheimer's disease than in normal controls. This reflects ultrastructural
changes in the hippocampi. Similar changes are also noted in other parts of the
brain. This however does not translate into clinical use to diagnose Alzheimer's
disease due to overlap with normal subjects, but as the authors say would be useful
in drug trials and longitudinal follow-up. A commentary on this by Shwartz R B
is also available in the same issue. | |
| | Click
here for abstract | | 
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