CARDIOVASCULAR DISEASE Bermuda’s top killer
Cardiovascular disease is the number one killer in Bermuda. In 2006, it accounted for 41.2 percent of all deaths. Cholesterol build-up in the arteries atherosclerosis is one of the main causes of cardiovascular disease.
But although tests to determine the amount of cholesterol in your blood can be done, that doesn't tell doctors how much may be sticking to artery walls, forming plaque and narrowing the space through which blood can flow to the body.
To do this you need to be able to look inside the body and take pictures of the scene there. If you could look inside the body and see the blood going through the arteries, you would see where it was getting held back, moving slower or not moving completely through much like looking through clear drain pipes to see where the clog is.
That's what computed tomography scanning (CT scans) brings to medicine. And it's what doctors at Bermuda Health Care Services said they would find most helpful in treating and diagnosing their patients.
Medical director, former Premier Ewart Brown said his physicians' preference to have a CT scanner over a digital mammogram machine was the main reason he decided to expand the practice in this direction.
A 64-slice CT scanner is housed in the Brown Darrell Clinic in Smith's. It is the most powerful imaging machine in Bermuda and the only one on the Island at the moment although King Edward VII Memorial Hospital has plans to install one next year.
“CT scanning is good for looking at the heart and everything in the abdomen the stomach, the pancreas, the liver,” said Dr Brown.
He explained that MRIs and CT scans are used in different circumstances.
“The CT is more effective and more revealing in the abdomen and chest. That's where it is really excellent.”
The scan is able to pinpoint the exact location of a problem, he said.
“When I first used one I couldn't believe how clear we could see the arteries going down to the legs,” said Dr Brown. “The patient had been complaining of leg pain on exertion which is almost always a sign of arteriole narrowing and the blood cannot get through but we didn't know exactly where it was or how bad it was. We put him on the scanner, infused the dye and then watched as the dye came down.
”[The machine] alerts you and also records it.”
It's an important method of diagnosis, Dr Brown added. As such he plans to offer physicians seminars on the latest research on CT scans and heart disease.
The scan shows where arteries are blocked and where they are narrowing.
“Men in their 40s and 50s with a strong family history of heart disease could get cardiac studies and find out things about their circulation that they have no clue about today,” he said. “In the treatment of heart disease you don't go right away to open heart surgery. Sometimes, a 40-year-old man who may show early signs of sclerotic heart disease could be treated medically.
“His cholesterol might be sky-high but no-one knows what his arteries look like.”
The potential of the doughnut-shaped machine to save lives in Bermuda is great, he added.
CT technologist Twanna Watson showed Body & Soul scans of a 22-year-old patient who had stage four cancer.
The images revealed within 20 seconds that a bump the patient felt on their neck was actually one of several clusters of cancer cells throughout the body.
Cancer had not been suspected in this case and the patient flew overseas for treatment the same day.
She said the quick results afforded in CT scanning mean treatments can start sooner. They also reduce anxiety and worry when favourable results are returned.
Three medical professionals are on hand at every CT scan at Brown Darrell Clinic: a radiologist at the Lahey Clinic in Boston, Massachusetts joins by teleconference while a physician from Bermuda Healthcare Services and CT technician Twanna Watson sit in a ‘control room'.
Ms Watson explains the procedure to the patient and takes direction from the radiologist on what part of the body will be scanned.
“I don't assume that because the patient has complained of headaches, that we are going to scan his head,” she said.
Depending on what the physician is looking for, and what area of the body it is in, determines exactly how the CT scanner will be used.
In cases where artery blockage is being looked at a dye may need to be infused into the body. The dye will show as white on the scanner. If the purpose of the scan is to find kidney stones, no dye will be injected because kidney stones already show up as white. If blockages in the sinus are being looked for, they will clearly show without dye as well.
Ms Watson noted that it is unethical to force patients to have the dye however those who choose not to are warned that the full benefits of the scan may not be realised.
“We still do the scan without the injection and the radiologist still reads it to the best of their ability,” she said.
The patient lies on a gurney attached to the machine and is positioned within the doughnut shape to allow the relevant part of the body to be scanned.
CT scans are a form of radiation but the dosage and exposure are very small. Ms Watson said scans are completed in 36 seconds or less. The short exposure-time is one of the most important features of the powerful machine, she added.