Don’t forget about the linear probe!


    Don’t forget about the linear probe!


    Chief Complaint: Pregnant, vaginal bleeding

    An evaluation of first trimester vaginal bleeding certainly entails a pelvic exam and a bedside ultrasound to eval for ectoptic pregnancy. We are looking for an intrauterine pregnancy. You know the feeling. Please, just let me visualize an IUP!

    If you still haven’t tried using the linear probe to visualize your IUPs, give it a try already! We’ve discussed the use of the linear probe in your bedside transabdominal ultrasounds to confirm IUP before. It’s become a regular part of my practice, but I find that is still hasn’t fully caught on as an option for many providers yet. Here’s a few additional tips on using the linear probe for finding your IUPs.

    I still start with the curvilinear probe not only to see if I can identify a gestational sac with a yolk sac but also to get a full view of the entire uterus to ensure that I am looking in the right place. The curvilinear probe has lower resolution but can penetrate deeper for a wider view. Unless I can get a completely clear image of the IUP on this view, I will then proceed to the linear probe to get a higher resolution image of the IUP. In 1/3 of cases in which we were previously unable to fully visualize an IUP, using the linear probe will reveal a clear IUP. This saves us from requiring to use the endocavitary probe.

    You may have to adjust the depth going from the curvilinear to linear probe in order to center the IUP on your screen. You can also try increasing the resolution on your curvilinear probe first to see if you can visualize it adequately after that. You should still take clips in two planes. Make sure to fan through the uterus completely in both planes with adequate capture of the yolk sac in the gestational sac. I save images and clips using both probes.

    Now, of course, if you can’t visualize it clearly on your transabdominal ultrasound with either probe, then you still proceed to the endocavitary probe. But you’ll find that having this additional trick in your pocket will help you out more often than you think. Good luck finding those IUPs!


    (Yeah, I’m citing our own prior blog post on this topic)

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