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Interview with Dr. Fergus Coakley: Virtual Colonoscopy

Audio Interview

Hear a Patient Power interview with Dr. Fergus Coakley, a radiologist, discussing virtual colonoscopy. UCSF Medical Center is one of the few centers in California to offer virtual colonoscopies with the latest generation of CT technology. The procedure uses safe, non-invasive X-ray technology to create detailed images of the colon and surrounding organs, compared to a conventional colonoscopy that uses a six-foot long scope inserted in the colon.

Interview Transcript

Introduction

Andrew Schorr:

Virtual colonoscopy is less invasive and faster than standard colonoscopy for colon cancer screening, and colon cancer screening is very important these days. Virtual colonoscopy doesn't require sedation. Meet an expert in virtual colonoscopy next on Patient Power sponsored by UCSF Medical Center.

This is Andrew Schorr with Patient Power. Thank you for joining us. This is where we connect you with a leading medical expert from UCSF Medical Center and learn about a significant medical topic.

In my family one topic that we think about is colon cancer, which has happened in our family. We're very concerned about it. We want to be screened. We don't want anybody to be affected by it as we move forward, and so the question is how do you screen for it? Do you have a simple exam with your primary care doctor or do you need a colonoscopy, which many people have heard about. Some people know they'd rather not have it because there's some preparation, but that's not the best way to go if you really want to screen for colon cancer.

Recently, there's something called virtual colonoscopy, so we wanted to understand where that fits in. Joining us now is Dr. Fergus Coakley. He's chief of the abdominal imaging section of Radiology at UCSF Medical Center.

Dr. Coakley, so virtual colonoscopy, what is it? Is it a CT exam exactly?

Dr. Fergus Coakley:

Correct. It's a special type of a CT scan where we take images through the patient's abdomen, and then use a computer to reconstruct those images and give us a view that looks just like the "Innerspace" movie where we can fly through the large bowel, that is the colon, and see if we see polyps that may eventually turn into cancer, and that is the primary purpose of this test.

I should of course say that patients and your listeners should be aware that this is still a study that needs a routine preparation, which is somewhat unpleasant, but the colon needs to be empty before we do this study. It involves the same preparation that you would need for a regular endoscopy. However, we don't need to sedate patients for this test. So, for example, you could go back to work that same day if you needed to.

We insert a very small tube and inflate some air during the test so that the colon is inflated. That gives us better pictures, but it's not the very long tube that gets pushed all the way into the large bowel that's used during a colonoscopy. For better or worse, I think a lot of patients are reluctant to have regular colonoscopy even though the recommendation is that everyone over 50 should have that done. Virtual colonoscopy offers, as it were, a second line option for people who want an alternative.

The Importance of Screening for Colon Cancer

Andrew Schorr:

Let's talk about screening for colon cancer in the first place. Why is it so important? Where are we with the incidence of colon cancer today and as our population ages and why is screening so important?

Dr. Fergus Coakley:

Well it's really regrettable, and I do a lot of scans on patients who have advanced colon cancer that's incurable, and we believe that most of those patients could have been spared their disease if they had had their screening test of colonoscopy, be it a regular colonoscopy or virtual colonoscopy, to detect the early cancer, that is, those small polyps that turn into cancer. And colon cancer, because not enough patients get screened, remains the second leading cause of cancer death after lung cancer, so it's a really big public health problem that we still need to get our hands around.

Andrew Schorr:

So people then should have screening, and of course in my family we know that all too well. What is the recommendation now? Is it for anyone over 50 should have that screening or if there's bleeding or a family history it starts earlier? What's the recommendation?

Dr. Fergus Coakley:

Of course if you have some special risk factor, either family history or bleeding, that is if you have some symptom, you should obviously talk to your primary care doctor and see what is right for you, but for the general population the current recommendations are that you should start screening at age 50 with either a regular colonoscopy or nowadays you also have the option of virtual colonoscopy.

Pros and Cons of Virtual Colonoscopy

Andrew Schorr:

Now UCSF is one of the early centers, and you're one of the leading experts in this. Dr. Coakley, tell us where it fits in. So since you're not putting something inside where you could snip out polyps if you needed to right then or do biopsies, then when does virtual colonoscopy fit in somebody's screening over possibly many years. When would it be right?

Dr. Fergus Coakley:

That's a very good question, and I should add that one of the leaders in this field is Dr. Judy Yee who's another faculty member who works with the VA but also in my department — that is Radiology — and she has the luxury of having a gastroenterologist that she works very closely with, and so if she finds something abnormal at the CT colonoscopy, her patients can go straightaway to a regular colonoscopy if they need a biopsy.

That's not a service that we're able to offer yet outside of the VA Medical Center. It's logistically challenging and administratively difficult, so again this is one of the downsides at a lot of places of virtual colonoscopy is if we find something, which will happen in maybe 5 to 10 percent of cases, that you will then need to go on and have a regular endoscopy to have that finding confirmed and potentially have a biopsy performed.

As I said, CT colonoscopy I think is a good option for some patients, particularly those patients who are afraid or reluctant to have a regular endoscopy. If you're very frail or there are other reasons you don't want to have sedation for example, or if for example you've had a previous colonoscopy that was totally normal so you're pretty unlikely to have a new finding, those kinds of patients I think would be good candidates to have virtual colonoscopy. It may not be for everybody.

Andrew Schorr:

It shows how the field is moving though too and radiology being able to look inside the body without having to kind of poke up in there. So where is this headed?

Dr. Fergus Coakley:

One of the big issues this year that we expect is to get a decision from Medicare as to whether they will reimburse for a virtual colonoscopy, and that of course would give huge momentum to this technology. At the moment reimbursement is somewhat variable and will depend on your insurance carrier. We can't guarantee that we'll be reimbursed. Some patients do opt to pay for it themselves, which is also an option, but as I say if Medicare does decide to reimburse that could really push this forward and open the gates to this being used much more widely.

Andrew Schorr:

Using widely colon cancer screening would seem to be a good thing like you mentioned. You don't have to be sedated. I know for me it's kind of like a two-day affair if you're having a traditional colonoscopy where the first day you're kind of preparing yourself and cleansing yourself and then the next day because of the sedation you're kind of out of it. So it would seem like just from a productivity point of view if we're trying to screen many more people it would have its place.

Dr. Fergus Coakley:

Not everybody necessarily wants to go back to work after having their colon examined, but for those who do certainly virtual colonoscopy is an option. I would emphasize you still need the preparation and the colon cleansing. So yes, you can't get out of that, but the good part of it is that you will skip the sedation so if you want to drive yourself to the clinic or the hospital for this test you can do that. If you want to drive home or go back to work that's an option as well.

Andrew Schorr:

Let's understand radiology in this regard at UCSF. You all though are leaders in this field, so as you said Dr. Yee is working out procedures, and it sounds like though you continue to push the envelope to see how can this best be used.

Dr. Fergus Coakley:

Correct. We're still teasing out the details. There was a very important study in the New England Journal of Medicine last year that showed this technique had about 90 percent accuracy when compared with standard colonoscopy, so we now know how accurate it is. There are still some unanswered questions. What is the appropriate amount of colon cleansing that is needed? Can we make this a gentler, kinder exam for the patient that doesn't need maybe quite so much prep work? What is the best way to look at these images after we get them? There is some debate about using computer-assisted diagnosis and other advanced technology, but I think the headline question of "is it accurate," that has been answered, and these background questions are probably of less interest to the general public.

Andrew Schorr:

Let's ask about computing technology and power for a second because a lot of that helps drive radiology for you to see more less invasively. So I know where we are now. So virtual colonoscopy is new on the scene, and your understanding who it's right for and when, but all of us would love for you to be able to look in the body without being inside it, and if as you said these cleansing procedures were kindler and gentler.

As computer power increases, do you think you'll have imaging whether it's a year from now or five years from now so that this will be shorter and simpler?

Dr. Fergus Coakley:

There is some interest in doing what's called the "prepless" virtual colonoscopy where you don't need any cleansing at all, and there may be ways we can do that, and there are some studies looking at that. We're not there yet. You would probably still need to have the colon inflated because that's an important part of this study, so we would still be inserting a small tube into the rectum to inflate the colon and get good distension, so I don't think we'll ever be able to avoid that part of it, but it may become, as I say, less unpleasant for the patient as the prep and the technology to look at these images after the fact gets better.

Andrew Schorr:

Just so we understand what we have now at UCSF. So that would be an option for some people, and you talked about the different groups where it may apply, a virtual colonoscopy, and so you're not sedated; you still have to be cleansed; and there's this small amount of gas I guess that you're putting in so that you can inflate the colon to see it most appropriately. Did I get it right?

Dr. Fergus Coakley:

Yes absolutely, and let me just say we use carbon dioxide to inflate the colon, and there's a reason we do that. That gas gets absorbed very quickly. If you just use room air to inflate the colon it turns out patients get a lot of cramping and bloating and discomfort afterwards, but we at UCSF, and some other centers use carbon dioxide to make this, again, a kinder, gentler procedure for the patient.

Andrew Schorr:

How long does the procedure take?

Dr. Fergus Coakley:

The actual set of images is probably acquired in the matter of 10 to 20 seconds. We get two sets of images. Realistically from the moment you arrive at the outpatient imaging clinic to when you leave would probably be about an hour.

Andrew Schorr:

Okay, and if someone is sedated it's usually what two to three hours?

Dr. Fergus Coakley:

Yes. We want to make sure that they come around and they've woken up, and of course we recommend that they don't drive themselves home and then you need to have someone to come with you and who can take you home. So it makes it a little bit more complicated for patients to organize.

Andrew Schorr:

At the end of the day then it's really in consultation with your doctor whether or not this procedure, which is now available, is right for your personal situation?

Dr. Fergus Coakley:

I think that's absolutely true as with any of these new technologies and tests. You should make the decision and get the information you need from your primary care doc, but we also have some information on our website for those who are interested.

Andrew Schorr:

Okay, well I think we've covered it pretty well with you Dr. Fergus Coakley, chief of abdominal imaging at UCSF. I wish you well with this new virtual colonoscopy, and I hope people that it's right for will take advantage of it at UCSF, one of the leading centers for this.

For more information about either the physicians or the services at UCSF, call the UCSF Physician Referral Service, and that number is (888) 689-UCSF (689-8273). Dr. Coakley, thank you so much for being with us on Patient Power. We wish you well as you continue to advance abdominal imaging at UCSF.

Dr. Fergus Coakley:

You're welcome. The last thing I would say to your listeners — irrespective of whether you get a regular colonoscopy or a virtual colonoscopy — is it's critically important that anyone who should be screened for colon cancer get screened because this is a preventable disease. We want to see less and less of the advanced disease that we can't cure.

Andrew Schorr:

Absolutely, and having lost a dear family member to advanced colon cancer, I couldn't agree more. I'm Andrew Schorr. You've been listening to Patient Power sponsored by UCSF Medical Center. Remember, knowledge can be the best medicine of all.

Recorded January 2009

 

Reviewed by health care specialists at UCSF Medical Center.

This information is for educational purposes only and is not intended to replace the advice of your doctor or health care provider. We encourage you to discuss with your doctor any questions or concerns you may have.

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