Martin Necas, RDMS, RVT

Articles

TRV Chest, Abdomen, Head Hydrops Fetalis

SAG Uterus, Twin Gestation Stuck Twin Syndrome in TTTS

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: "Hi, I’m Martin     Necas the Ultrasound Coordinator for 

 Annual Convention in San Francisco and     sitting with me is Dr. Timor-Tritsch who is from the New York University     Medical Center. He has been giving presentations here at the conference, and     one particular topic that I found of interest was his discussion about 14     week transvaginal anatomy scans. I was wondering if you could give us a     little bit of an overview about this technique and how you find it in daily     practice?"

: "It     really is a 14-16 week transvaginal scan and the prerequisite for it is to     have a reasonably good high frequency machine or a transvaginal probe and     the knowledge of anatomy at that gestational age. What it entails is     checking the fetus from head to toe and from inside to outside. There are     lots of advantages to it because first of all the high frequency vaginal     probe can encompass the entire fetus at that gestational age so it gives you     a very high resolution picture. The other advantage is that the fetus is     mobile at that time, most spontaneously or slightly helped by the     abdominally placed second hand of the operator so you can really change and     get into focus all the organs and organ systems that you need. Basically, it     was pioneered in Israel and immediately followed by some operators in the     Netherlands, Denmark, and in Germany, and once again, as you have heard in     my presentation, unfortunately does not penetrate the USA obstetric and     gynecologic community."

:     "What do you think is the source of this reluctance on the part of the     American sonography or sonologists community to pick up this technique and     make it a part of the routine intranatal care?"

:     "There are several ingredients to this hesitancy of the United States     to this technique, and I will go through them real quick because as you     heard it was almost a 30-minute lecture. First of all, is the fact that     there are no good outcome studies published in the American literature. That     also carries a very severe critique of mine of the American journal editors     who were unable to overcome some of their personal opinions and rejected     most of the articles that were submitted even on a large number of these     patients done outside the United States. The second reason would be that     most of the studies are published in foreign journals and even though they     are in English, they are published in journals that the American obstetric     and gynecologic community does not read or not journals that everybody     reads. The third ingredient would be that in the United States,     unfortunately, the routine scans of a pregnant patient are still debated and     still not customary. Although there is a lot of improvement and every excuse     is used by the patients and by the doctors to get the scan, I still don’t     think that more than 50%-60% of the patients are scanned in the United     States in pregnancy. The other reason would be that managed care wouldn’t     reimburse it, and obviously many of the American obstetrician-gynecologists     will not work unless compensated. And indeed, some of the people at the     conference asked me whether these are lengthy scans or not and they are. As     a matter of fact, they are at least a 20-30 minute investment from the part     of the physician or the sonographer so basically, these would be the major     reasons. But there are some minor reasons – pregnant American women are     not sufficiently informed either by self-education or by their     obstetricians. Maybe they are not connected to the Internet to see sites     such as this one for a good example, and therefore, the interest is somewhat     less than I see in Europe and in Israel where I know the situation really     well because some of the Israeli operators were my pupils, so I know exactly     how it is. For instance, in Europe and in Israel, women do not go for a scan     with a referral slip from their doctors. They just call up the doctor and     say - I would like to have a scan. How come they know that the scan is     available? So here is the difference between the American pregnant patient     and the European or the Israeli pregnant patient. Here in the United States     you have to have a referral slip, and once again, the obstetrician may not     want to give that referral slip or does not even know that this modality     exists. So here in a nutshell are some of the reasons that I see as a     problem here in the United States."

: "I     see, do you think that as the attitudes towards transvaginal anatomy scans     change amongst the professional community as well as patients that the scan     can actually replace the routine anatomy scans that we’re doing today at a later gestational age?"

: "Here     is the misconception that most of the obstetricians and probably some of the     representatives of the governing bodies think in general the technique is     pushing to replace or to eliminate the later transabdominal scan. This is     absolutely a misconception because this early anatomy scan which probably     detects 85% of the malformations or probably even a little more will not     push out or replace the transabdominal scan which is done slightly later at     around 20-22 weeks which should really be a complimentary scan. Together     they should render a 90%-95% detection rate so both have to be done in order     to yield a very high confident limit or confident to the pregnant     patient."

: "How     does nuchal translucency screening fit into this picture? If we were to     perform a routine nuchal translucency, say, from 10 weeks onwards, then a     transvaginal anatomy scan at 14-16 weeks, do we then repeat an anatomy scan     at a later gestational age? It seems that there will be limits to the     sonographer resources."

: "This     is an extremely important question, and I have two answers to this and I’ll     give you both of my answers. First of all, what is wrong with scanning a     pregnant patient three times? As a matter of fact, if I have a suspicion     that I have a heart problem, I will go to my internist once, twice, three     times, twelve times - as many times as I need to clarify the situation. What     is wrong with scanning that pregnant patient three times in the first part     of the pregnancy? As far as I’m concerned, this is an investment for the     next seventy or ninety years for that person who is just about to come into     the world. So this is one answer, and of course, you will also have to     substantiate this with resources and you said there may not be the amount of     machines, sonographers, sonologists, facilities, or machines available to do     this. But then there is another compromise that I see coming up - machines     are becoming increasingly better and yielding higher resolutions. So maybe     the nuchal translucency scan which is done up to 14 weeks we can have a     compromise by doing that vaginal structural evaluation close to or at 14     weeks with a good machine including nuchal translucency and then pushing out     the limit of the second scan to about 20 or 22 weeks when the confirmatory     transabdominal scan can be done. I see this coming because even now we have     at least one or two true top of the line machines with transvaginal but also     with transabdominal transducers that can do a good job at 14 weeks so maybe     that will be a compromise. But once again, I see absolutely nothing wrong     with a pregnant patient who would like to invest the time and maybe the     money to get three scans in pregnancy. As a matter of fact, if you would ask     me, and you didn’t, whether I believe in the fourth scan, I will tell you     that I would like to have another scan at around 7 weeks to make sure that     there is not an ectopic pregnancy at the very beginning or not a     non-developing early embryonic demise which is 10% at that gestational age.     So I would be in favor of four scans in a pregnancy, and of course, the     fifth one at around 28-32 weeks for a growth scan so this would be my agenda     for money really well spent maybe in a package for a pregnant patient."

: "Dr.     Timor-Tritsch, I would like to thank you for the interview and for giving us     a bit of a perspective on the transvaginal anatomy scan and a little bit of     an overview of perhaps what we should expect in the future. Thank you very     much."

OBGYN.net Conference CoverageFrom AIUM 44th Conference held in San Francisco, California - April, 2000

Transvaginal Anatomy Scan

: "Hi, I’m Martin     Necas the Coordinator of the Ultrasound section of 

 Annual Convention of AIUM with Dr.     Smeltzer from Atlanta, Georgia. James is one of our Editorial Advisory Board     Members and he’s also very active on the Ultrasound Forum. James has been     here having a great time in San Francisco and seeing some of the     presentations as well, and today we’re going to just briefly touch on two     topics - one is sonoelastography and then we’ll talk a little bit about     nuchal translucency. So let’s turn to the first topic, James, could you     tell us a little bit about what has been done in sonoelastography and how we     can implement it in our practice?"

: "Sonoelastography     is a new issue with me but it’s very exciting. As you know, one of the     difficulties with ultrasound is figuring out whether a particular mass is a     cancer or malignancy or not. Based on the sonoelastographic properties, it     is possible to distinguish between malignant and benign lesions especially     of the breast and with a fair degree of reliability. I just learned that in     a nice, beautiful course that was here this morning and will be continued in     the afternoon. In addition, I know a student of mine who collaborated on     several research projects with me, V . Dogra, who’s now a radiologist, was     here presenting on sonoelastography in the liver in oral presentation which     I missed because I didn’t know he was going to be talking. But we spent a     delightful evening yesterday talking about this exciting topic, and I     believe it will be very helpful to us in the future clinically."

: "Do     you think that the technique can also be implemented in other organ systems,     for example, in superficial structures or the kidney?"

:     "Superficial structures - yes, definitely and it can be used for that     purpose in the breast as well. In the liver they demonstrated a benefit, and     in the kidney I think it may also demonstrate a benefit but it’s a little     early for that."

: "Are     there certain technical difficulties with demonstrating sonoelastography     properties in deeper tissues?"

: "There     was very interesting data presented today about the difference of the     frequency response of varies benign tumors in the breast. Some people have     reported excellent discrimination by so called fremitus having the patient     hum, and others have reported very poor results. It may be that people in     different parts of the world hum at different pitches because one group     found a very definite frequency response of humming with benign tumors but     it turns out that malignant tumors pretty much are like a rock, they don’t     move at all, and that is the way that you discriminate between benign and     malignant."

:     "Yes, this is certainly a hot and exciting new topic, and I’m sure     more and more research will be done in this area. Perhaps next year in     Orlando, Florida we’ll have the pleasure of seeing more of these     presentations and learn what has been done during the year. If I may, I’d     like to talk a little bit about our second topic, which is nuchal     translucency. You do some work yourself in ultrasound, you’re a very key     member of our forum, and I was wondering if you could give us a little bit     of an overview of what nuchal translucency means to you and how you put it     in your practice?"

: "For the     last several years, at least the last four or five, we’ve used it as a way     of detecting women who have infants with aneuploidy. Personally, there’s     only one with a heart defect but it can also be used for that and other     major anomalies. Done between ten and fourteen weeks, Nicholides group in     England in very large studies have shown a remarkable ability to predict and     identify most babies with Down syndrome. We’ve used this information in     our practice, and very few of our women now over 35 get amniocentesis and a     high proportion of the ones that do, have positive amniocentesis for     aneuploidy. I’ve always felt that was a much more satisfying thing; the     nuchal translucency is a way for someone that’s adequately trained to     identify about five out of six babies with a serious aneuploidy. Some of the     American studies have shown that it does matter how much training you have     because they were unable to reproduce Nicholides results. People really do     need to be trained and certified in this technique to use it on a regular     basis although all the misses and false-positive diagnoses that they’ve     reported are not my personal experience. Several studies have indicated that     attention to exactly how you do it, having the proper images, discriminating     between the amnion and the nuchal lucency, and being sure that you’re     measuring it in a neutral position and measuring it properly from edge to     edge and not from edge to skin is very important."

:     "Yes, certainly ultrasound appears to be a very operator dependant     technique. I think the Nicholides group has tried to bring in a certain     level of absolute objectivity so that there’ll be very little space for     error in intra-observer variability. Do you find that the nuchal     translucency measurements are highly reproducible?"

: "We have     not done formal reproducibility studies in our laboratory, others have.     Where ever you pay attention to how you do them, they are highly     reproducible, and more important, they are very highly predictive of     clinical outcome. In our practice in a fairly captive population, we’ve     had no unidentified babies with Down syndrome born that were screened with     nuchal lucency."

:     "Yes, and that’s a remarkable success rate. I remember you quoting     this particular fact on the 

: "Either     lucky or good, a good sonographer is the key, I think."

: "I     also believe it’s all in the quality. Thank you very much just for talking     to us and we’ll be looking forward to seeing you on the forum again."

Martin Necas, RDMS, RVT

Articles

TRV Chest, Abdomen, Head Hydrops Fetalis

SAG Uterus, Twin Gestation Stuck Twin Syndrome in TTTS

Transvaginal Anatomy Scan

Sonoelastography and Nuchal Translucency