Lecture 9 Flashcards
(12 cards)
How does imaging help?
It helps to diagnose and guide treatment of renal tract abnormality and disease. You will listen to the patient, ask questions and you can diagnose the problem (90%). After this you use imaging to confirm the diagnosis and where it occurs; or surprise that it wasn’t what you thought. Then come the blood tests, urine tests, ECG and maybe imaging.
What is the type of imaging used for renal?
- Plain film - XRAY.
- (Intravenous urogram IVU) - watch dye coming out of the kidney (being replaced).
- Ultrasound.
- MRI.
- CT.
- Nuclear medicine.
What is the first imaging used?
Plain Film.
Why do the use a plain film in terms of renal?
It is cheap. However it does use radiation. radio-opaque stones (however, there are non-radio-opaque stones).
What are radio-opaque stones?
Stones with calcium in them, you can see as it is like calcium in the bones. They show out as white blobs/circles in the plain film.
What are the stones that don’t have calcium in them?
Patients who have gout, or high levels of uric acid, grow uric acid stones. These are more common in the Maori population. Definite stone, however you cannot see them. However, you need to do a pre-test (probability).
How does a patient present with a kidney stone that is making its way out of the kidney and down the ureter?
The present with loined-groin pain. In men it can present initially in the testes (referred pain). The patient could have blood in their urine, there would be no fever and it would be the worst pain a person could experience. You are asked not to operate on the patient laboring under the stone (don’t operate on someone who is undergoing a kidney stone) - under the Hippocratic Oath. The patient is extremely restless. The little stones are the ones that can cause the problems as they move down the ureter.
What is the pain like in a person with an appendicitis?
The person is so sore for them to breathe, so they don’t move.
How wide is the ureter?
5mm. it can’t stretch further except over a long time. A stone beyond 5mm get stuck, however the ones smaller than 5mm do cause pain.
How do you use an IVU for renal?
You use a plain XRAY however contrast is injected.
how does ultrasound work in terms of renal?
It uses high frequency sound waves, there is no radiation and it is operator dependent. It is patient related (body habitus dependent - the fatter the patient is, you still only have one frequency of sound i.e. harder to get down to kidneys when they’re bigger). It’s useful for renal stones, renal obstruction, renal mass and bladder lesions (cannot assess ureters - need to get through the body and air is deaf to ultrasound).
What does the renal capsule look like on the ultrasound?
It comes up as a echogenic line.
