Additional Investigations – Investigation and Diagnosis of Blood Disorders

00:00 There are many other investigations, which you can do within a patient with a haemotological condition, but imaging is key in many cases. This is looking at the anatomy of the body using procedures such as x-rays or these investigations: ultrasound, CT scan, MRI and PET imaging.

00:25 Lets look at these in a little bit more detail.

00:30 An ultrasound is particularly useful in assessing the size of some of the abdominal organs such as the liver and the spleen. We will see on the right there, representation of a liver.

00:45 Splenomegaly is common in a range of haematological disorders and certain examination of the spleen is a key component when examining a patient with a haemotological condition.

00:59 A CT, a computed tomography scan is very commonly used in patients with disorders such as a lymphoma.

01:08 You will see on the right, they give very detailed assessment of the anatomy of the body, usually a contrast medium is given to the patient and that helps to increase the resolution of the scan and improve the information that can be derived from it. Of course, CT scans do involve the use of x-rays and an abdominal CT use quite considerable dose of x-rays. Let us look that example on the right of the CT scan.

01:36 Imagine yourself looking out from the patient's feet into that CT scan, you will see obviously the vertebral column in the middle and on either side, two kidneys and just at the left you'll see the liver starting to appear and just right to the liver, just above the kidney, you will see a massive lymphoid tissue and this is a patient with swollen lymph nodes within the abdomen, in this case a lymphoma.

02:04 Magnetic resonance imaging is more recent technique that's now widely used in hospitals around the world.

02:13 MRI scans generate very highly accurate images of the body that is superb for examining the brain or neuromuscular images. They do take longer than a CT scan, but usually they don't use x-rays and for that reason they can sometimes be preferred. You'll see on the example here, a very beautiful example of the vertebral column and the spinal cord taken using magnetic resonance imaging and I dont know if you spotted the abnormality within that picture, but if you look down the vertebral column, you will see that one of the vertebrae is highly compressed and that is the patient who had the malignant disease and one of the vertebrae has collapsed.

03:06 Now a relatively new imaging technique which is widely used now in particularly in lymphoma management is the Positron Emission Tomography or PET scan. This is really quite interesting and sophisticated approach and in this, a radiolabelled form of glucose is injected into the patient.

03:27 it is quite interesting that most, if not all cancers take up a lot of glucose to fuel their growth, It's glycolysis which we do not entirely understand. Scientists call it the Warburg effect.

03:42 This means that when we inject this glucose into a patient who has the malignant disease, the malignant tissue tends to take up this radiolabelled glucose and then we can use scanners to see where the label has gone. We can combine this PET imaging with CT scans and PET/CT is a very powerful way of looking for areas of malignant disease. You'll see on the right a nice example of a PET scan with the colored areas, not the blue, but the green and the red showing where cells have taken up the radiolabelled glucose. The bottom, you can see the bladder is lit up because that's where the urine has got the label and that is going to excreted, so we can ignore that.

04:33 and you'll see if you look on the right that in addition to the bladder it is red you'll be red areas which reflect the areas of the tumour particularly as you'll see within the vertebral column representing metastasis of the tumour and so imaging can actually Direct you to where the tumour is position So we now know where the disease is. PET scans as it says at the bottom there, are not just useful in diagnosis, but we can also use them to guide the treatment because they might be used to tell us when we can stop therapy or when we need to give more therapy so they can be used to tailor the treatment of individual patients so as not to give too much chemotherapy than is needed.

05:26 But all these information has to come together: history, examination and investigation.

05:32 This requires input from a range of experts and these days most patients can discuss at meetings of all sorts of specialists, doctors, nurses, pathologists, x-ray doctors.

05:46 Now an accurate diagnosis can be made in the great majority of cases.

05:51 So in summary, the history, examination and investigation must be used together to make an appropriate diagnosis.

06:01 The blood count is a crucial first step and i've shown you that there are many important facts and information that can be derived from a blood count.

06:13 But a range of investigations are now available to us to use: detailed blood tests, bone marrow examinations, genetic analysis and imaging tests and together these can be used to get the correct diagnosis for your patient.

06:31 Thank you for watching the lecture.