pujo nuclear scan dtpa

1. Renal Nuclear Scan in PUJO
Dr G
Praveen Chandra

2. • DTPA or renal nuclear scan is done to know
the precise function

3. Choice of Ix for fn study…………
• Diuretic renography MAG-3
• B’coz MAG-3 has total tubular secretion so not
affected by GFR.
• In most centers, mercaptoacetyltriglycine
(MAG3) has replaced diethylenetriamine
pentaacetic acid (DTPA) as the radionuclide of
choice

4. • MAG3 is both filtered and secreted by the
renal tubules, it is more useful in immature or
chronically insufficient kidneys than is DTPA.
DTPA is filtered only by the glomerulus and is
not actively secreted by tubules

5. There are three parts of a given renal nuclear
scan
• 1. The picturistic/ images of the kidneys
• 2. The graphical representation/curve
• 3. The numerical values.

9. Picturistic/ images of the kidneys……..
• The images given are actually 2 sets of images
– 1st one represents the perfusion phase and
images are taken @ 1 image per sec after injecting
contrast.
– Contrast usually reaches both kidneys
simultaneously and within 5 seconds .
– Thus both kidneys should be seen together after 5
second image.

10. • The second set of images are taken @ 1 image
per min and represent intra renal transient
time and excretion of contrast into PC system
and reaching bladder.
• Usually intra renal transient time (IRT) is less
than 4 min so contrast should be seen in PC
system by 5 images.
• Delay in IRT represents obstruction.

11. • Rest of the images represent the flow of tracer
from PC system to bladder

12. Graphical representation/curve
• The curve represents the graphical
presentation of the tracer movement across
the renal system .
• The graphs are called O’REILLEY CURVES or
time activity curves.
• Each graph has three lines 1st for aortic trace,
2nd and 3rd for the left and right kidneys.

16. Numerical values…………
• The third part of the report is numerical
values
• GFR, IRT and split function .

17. Advances in nuclear medicine methodologies
provide the opportunity to assess renal
function (GFR, ERPF and MAG3 clearance)
using either
plasma sample clearances or
camera-based methods.

18. • Plasma sample clearances involve blood
sampling.
Camera-based techniques do not require
blood or urine samples to measure GFR,
ERPF or a MAG3 clearance, but these
measurements are not considered to be as
accurate as plasma sample techniques and
require specialized software

19. According to the timing of Lasix
administration……3 protocols.
F + 20 - Furosemide is injected 20 minutes
after the injection of tracer.
• F (– 15) - Furosemide is injected 15 minutes
prior to the tracer
• F – 0 - Furosemide is injected at the beginning
of the study

20. • Renal scan in altered creatinine: Use tubular
agents
• DTPA can be done upto 3.0 mg/dl
• DMSA and MAG-3 can be done upto 7 mg/dl

21. • Less than 15% differential function and less
than 10 ml/min of GFR…. “non salvageable”
kidney

22. Thank You