A Cerebral Angiogram is the study of arteries and veins of the brain. This is performed by a radiologist, who is a doctor specifical y trained in these studies. It involves the insertion of a thin plastic tube (catheter) into the artery. This is usual y via the main artery in the groin. Time: The angiogram usual y takes about 60 minutes to perform, but we wil need to observe you fol owing the angiogram for 3 to 4 hours. This procedure can be performed as a day only or overnight admission. How to prepare: If you have any of the fol owing conditions please alert the radiology staff: asthma, Multiple myeloma, Kidney disease, Sickle cel disease, Myasthenia gravis, Phaeochromocytoma. If you take any oral diabetes medications, especial y metformin (Diabex, Glucophage, Diaformin) please notify the Interventional Neuroradiology (INR) Department on 9926 8505. You may need to stop your medications for 2 days before the angiogram and have your kidney function tested with a blood test 2 days after the angiogram before starting back on the diabetes medication. If you have had a prior contrast reaction you may need a short course of steroids prior for 24 hours prior to the angiogram to reduce the chance of you having another al ergic reaction. No special preparation is required and you wil not need to fast. What to expect: It is necessary for you to sign a consent form to confirm that you know about the risks and benefits involved with the test. Most angiograms are done with you awake although a mild sedation may be given before the study if required. You wil be taken into the angiogram room and wil be positioned on the angiogram table. The radiologist wil come and talk to you and explain more about the procedure. They wil examine the pulses in your groin and you may need a limited shave so that the artery can be approached easily. The overlying skin wil be cleansed and covered with sterile towels. A local anaesthetic (lignocaine) is given to numb the skin overlying the artery. The doctor makes a smal cut in the skin to al ow the needle to pass more easily. A needle is then inserted into the artery, through which a guidewire is inserted. The needle is then removed and fine plastic tubing (catheter) is passed over the wire. The catheter is positioned in the arteries in your neck supplying the brain. The dye is injected and x-rays are taken. When the dye is injected, you may feel a warm sensation, which some people find unpleasant. This is normal and nothing to worry about. Afterwards: You wil be moved back onto a hospital bed. The radiologist removes the catheter and presses on the artery in the groin for about 10 minutes. You wil need to lie flat in bed for 4 hours after the procedure to reduce the risk of bleeding. The nursing staff in the x-ray department wil observe you during this period, monitoring your blood pressure, pulse and examining the groin.
You must have a responsible adult to accompany you home after the procedure and ideal y stay overnight with you. After the angiogram you wil need to take it easy the only walking you should do is to the toilet or to bed. Do not undertake any strenuous activities/exercise for 2 days. If you notice any new swel ing or bleeding into the groin, you need to contact the Radiology Department on 9926 8505. Adverse Effects? There are some complications that may occur from this procedure. The most important complication to be aware of is the risk of stroke (between 1 in 200 and 1 in 500 angiograms depending on the age of the patient). Such a stroke may result in permanent blindness, paralysis and/or loss of speech. Other complications include:
Bleeding at the groin. This may show up as a bruise or lump and be uncomfortable for several days.
False aneurysm – pulsating lump develops in the groin after the catheter is removed. The lump contains blood which is connected to the artery through the hole made by the catheter. Treatment varies from pressure with ultrasound probe, injection into the lump causing the centre to block or rarely surgery to repair the damage.
Numbness and weakness of the leg – the local anaesthetic can numb the nerves down the front of the thigh. This wears off after an hour or two.
Al ergic reaction to the x-ray dye – skin rash, vomiting, asthma, low blood pressure, disturbance in heart beat.
Renal impairment – contrast can impair kidney function (temporarily or permanently) and occasional y may cause acute renal failure requiring dialysis. This is more common in people with pre-existing renal impairment, diabetes, heart failure and in the elderly. Giving special intravenous fluid before and after the study can reduce the risk of renal impairment.
More serious bleeding requiring a blood transfusion (3%) or a smal operation to seal the hole in the artery with a stitch (very rare)
Blockage of the artery at the groin stopping the blood supply to the leg
Damage to the internal arteries especial y if the artery is already badly diseased. Usual y these problems can be treated by the radiologist at the time of procedure. It may require surgery to fix the damage
Alternatives to Angiogram are:
CT Angiogram – the same contrast is used but injected into a vein in the arm rather than into an artery in the groin and CT is taken through the arteries of interest
MRI Angiogram – usual y no contrast injection is needed and an MRI is performed, using a large magnet to obtain images What about the Results? The radiologist wil study your films and prepare a written report. The films and report wil remain a part of a part of your hospital records. The doctor looking after you wil let you know the result.
This chapter discusses a forward chaining rule based system and its expert system applications. It shows how the forward chaining system works, how to use it, and how to implement it quickly and easily using Prolog. A large number of expert systems require the use of forward chaining, or data driven inference. The most famous of these is Digital Equipment Corporation's XCON system. It configures
Education above that which a healthy child of the same in the early stages of the illness, often before age would need. Just because a child has a the correct diagnosis has been made, it is particular disease does not mean that the recognised that there is going to be some application will automatically be successful, each case is judged on its merits. There is an most fam
Specialist Endovascular