0:00

This patient is post-opper day

0:03

one from a renal transplant and that we're evaluating

0:06

to evaluate the alligraph. This was placed in

0:09

the left lower quadrant since we start off with their grayscale images, we measure the

0:12

transplanted kidney. We ensure that there's flow

0:15

throughout the transplant of kidney, which there is you see a

0:18

sliver of a collection in the left lower quadrant over here measures

0:21

about five centimeters and it's length but that

0:24

itself is not too much to be worried about no flow

0:27

within that collection. So these are all sort of the general things we look for

0:30

we look for hydrantiferosis. We look for masses all that

0:33

is sort of reasonably. Okay, and we

0:36

then start to interrogate the vessels inside the transplanted

0:39

kidney itself. We look at the segmental orders in

0:42

the upper pull and we're seeing nice Sharps is all the gup Strokes.

0:45

So that looks okay, but look at the end diastolic velocity. We're

0:48

about three centimeters per second. That's very low. If you

0:51

calculate the resistive index from these values you're getting

0:54

a resistive index is 0.86. Remember that

0:57

in the post transplant patient. We're really liking

1:01

Resistive indices to be typically teen point six and point

1:04

seven upper limits 0.5 to 0.6 is

1:07

also reasonable, you know, when we start to get to point

1:10

eight we start to worry that there's some sort of increased vascular

1:13

resistance within this renal transplant when you're

1:16

starting to get to 0.86.

1:18

You are worried. And so that's just one sort

1:21

of snapshot. Let's look at some other vessels.

1:23

Here we have the interloper arteries in

1:26

the upper pull.

1:27

Good sharp systolic upstrokes, but again, the diastolic flow

1:30

is very poor. Now there is some sort

1:33

of venous background contamination because these vessels so adjacent

1:36

to one another and so this flow here is probably

1:39

all going to be venous flow. If you actually look at it. There's probably

1:42

very very little diastolic flow and you're really getting resistive index

1:45

of one over here, which is

1:47

Not very good at all. We're looking at some of the

1:50

veins as well and that same region followed by

1:53

the lower pole arteries. Look at this segmental artery, really no

1:56

diastolic flow over here resulting in a resistive index

1:59

of one inter liberal artery. No diastolic flow resulting

2:02

in resistive index of one. And so what you're really seeing

2:05

is a kidney that has very high internal vascular resistance

2:08

resulting in these high resistive indices.

2:11

Now, there's several ideologies of

2:14

this.

2:15

And the next thing you have to do is sort of look at the time

2:18

period in which this is occurring. This is a patient who's

2:21

post-op day one from renal transplant in this time

2:24

period the most common ideology for this is something called

2:27

acute tubular necrosis. And

2:30

this is thought to occur due to some sort

2:33

of vascular insult or ischemic insult that happens

2:36

to the real transplant during the

2:39

process of harvesting it and the transplant surgery itself.

2:42

And so typically this is much more common and deceased

2:45

donor renal transplants who may have been deceased for

2:48

a period of time prior to giving up their renal transplant

2:51

resulting in ischemia to that renal transplant. We

2:54

don't often see these with living donor transplants who are

2:57

alive or healthy or giving up one of their kidneys and

3:00

altruistic fashion. And so the big

3:03

finding that you're looking for this instance is high resistive indices.

3:06

When you see that in this immediate post-operative setting,

3:09

you know within the first three days you got to think about your

3:12

tubular necrosis and

3:15

Generally in the setting you just sort of do supportive treatment

3:18

and patients low resolve will get better. It takes

3:21

some times days sometimes weeks for them to resolve but nothing

3:24

much you can do beyond that this idea of

3:27

increased vascular resistance with high assistance can be

3:30

seen with a number of other diseases. But again, the

3:33

way you differentiate it from an Imaging perspective is the

3:36

time frame in which you're observing these findings.