This is indicated mainly for diagnosis of renal vein thrombosis. A
catheter is introduced percutaneously into the femoral vein then advanced
through inferior vena cava to the renal vein where the contrast medium is
injected.
- Computerized tomography (C.T.)
This scanning may be superior to other radiologic investigations in
the following areas: 1. To characterize lesions in peri-renal, para-renal and
retroperitoneal space as lymphadenopathy, tumours or retroperitoneal
fibrosis. 2. Solid renal masses, for diagnosis and staging of the tumour. 3.
Low density or radiolucent stones. Therefore it is strongly indicated in
patients with obstructive uropathy with non-evident cause (Fig. 2.8). - Radionuclide Imaging
There are two types of isotope renal scanning: 1. Static imaging, in
which the tracer injected is retained by proximal convoluted tubules,
giving best chance to visualize the morphology of functioning part of the
kidney using gamma camera. So, it is helpful in diagnosing renal scarring
(Figure 2.9), renal tumours and anatomic abnormalities. The tracer used
for this type of scan is 99m technetium-labelled dimercaptosuccinic acid
(DMSA). 2. Dynamic renal imaging in which the tracer is not retained by
the kidney, but is immediately excreted, either by glomerular filtration
alone e.g. 99m TC- diethylenetriamine penta acetic acid (DTPA) or by
glomerular filtration and tubular secretion (MAG3), and 123I, sodium
iodohippurate (Hippuran). This type of scan is helpful in diagnosing renal
vascular occlusion (embolism or thrombosis) or narrowing (renal artery
stenosis). The dynamic parenchymal imaging (Figure 2.10) helps in
diagnosis of ureteric obstruction in which delayed washout of the tracer
from the kidney will be observed. Furthermore, the dynamic scan can be