Læknablaðið - 15.03.1984, Blaðsíða 54

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LÆKNABLADID
from neoplasm and metastatic tissue from
reactive hyperplasia in lymph nodes would be
a significant advance.
In the liver the intrahepatic vessels and bile
ducts are clearly seen against the normal
parenchyma. It has been shown (15) that focal
diseases such as metastases are as weli seen
on NMR scans as on the corresponding CT
sections. In diffuse disease such as cirrhosis,
however, in addition to morphological infor-
mation the values of the organ are general-
ly prolonged. In biliary cirrhosis and Wilson’s
Disease where excessive copper is deposited
this paramagnetic material results in a short-
ening of the T| values.
More work is required to see whether NMR
will have a role in reliably characterising
pancreatic disease, both pancreatitis and neo-
plasm are associated with an enlargement of
the organ and a lengthening of the T, relax-
ation time.
The striking feature of renal images is the
clear discrimination between the cortex and
medulla on T, dominated scans and the
collecting system is also well seen centrally. It
is likely that NMR will be exploited more to
study diffuse, parenchymal disease rather than
focal lesions such as cysts which are readily
evaluated using conventional radiological
techniques.
The multiplanar facility of NMR has al-
lowed the spinal cord to be studied from all
three planes and high resolution Tj dominated
images have allowed discrimination of grey
and white matter within the cord. Sagittal
views of the spinal column allow the inter-
vertebral discs to be clearly seen and one can
distinguish the nucleus pulposus from the
surrounding annulus fibrosus (16). The signifi-
cance of these observations in relation to the
assessment of disc protrusions remains to be
studied in detail. Using flow dependence
sequences intrinsic vascular lesions such as
aneurysms can be displayed (Fig. 14) and
intra-luminal thrombus can be identified. With-
in the pelvis bladder tumours (Fig. 15), depo-
sits of lymphoma (Fig. 16) and gynaecological
tumours (Fig. 17 and 18) are well shown.
In the thorax the major vessels and airways
of the central mediastinum can be clearly
resolved and mass lesions can be well demon-
strated. In self-gated images of the heart the
chambers are clearly defined (17). Whereas in
CT bolus injection of contrast is required to
Fig. 13. Transverse scan through the pelvis of a
normal male subject intersecting the hip joints.
Note the seminal vesicles behind the bladder.
Fig. 14. Coronal scan in a patient with a large
aneurysm involving the abdominal aorta. An enlar-
ged prostate is also seen encroaching on the base of
the bladder.
Fig. 15. Sagittal scan in a patient with a large
tumour arising from the anterior wall of the bladder.