Situation: You’re covering #Neurorad CT-guided biopsies and this case shows up on your list.

Older patient with recently diagnosed clear cell RCC. Lytic lesion in the upper sacrum seen on CT Abd/pelvis.

How do you approach it? #SpineIntervention
1/6
Some options:
1. Anterolateral approach along the iliac bone.
👎 Long path, lots of bone to drill through.

2. Drill through the lateral aspect of the sacral arch to pass in between the thecal sac and the S1 nerve root.
😕 Durotomy risk 💦 and potential seeding 🫣

What else?
2/6
Using an 18-Ga as an introducer, you can FNA the lesion with a 22-Ga needle. But the S1 nerve root could still be an issue and there’s not a straight approach through the foramen.

But, we have two tricks up our sleeve that make this possible…
3/6
First, we can use a 22-Ga spinal to inject some dilute contrast to highlight the nerve root so we know where it is for the duration.

Make sure it’s dilute (~33% in sterile saline) so you can still see your needle.

And chase it with some lidocaine to block the nerve.
4/6
Next, we put a gentle curve on the end a fresh 22-Ga needle (NOT the one you used to inject contrast or lidocaine!) to slide medial to the nerve and into the lesion. Repeat as needed.

Note: RCCs are bloody and may require 3 or more passes to get a Dx.
5/6
Finally, if chordoma is on your DDx, you’ll want to get your introducer as close to the lesion as possible to minimize seeding.
h/t @PeterGKranz

6/6

• • •

Missing some Tweet in this thread? You can try to force a refresh
 

Keep Current with Walter Wiggins, MD, PhD

Walter Wiggins, MD, PhD Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!

PDF

Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @walterfwiggins

Jun 21
"Kids are not simply little adults."

This adage is repeated countless times throughout med school re: physiology/pharma.

I think it should apply equally to #AI. That's why this headline from @AuntMinnie concerns me greatly.
#RadTwitter #PedsTwitter
1/n

bit.ly/3xH7oX4
In the referenced article, the authors set out to validate @Lunit_AI CXR tool on a cohort of pediatric CXRs.

The authors explicitly state in the abstract that the tool was developed for ADULTS, not kids.
2/n

nature.com/articles/s4159…
Here are a few of the reasons why I'm deeply concerned by this:

#1 - We already have learned that #AI tools can fail unpredictably & inexplicably on data that falls within the distribution of the training data.
3/n
Read 8 tweets

Did Thread Reader help you today?

Support us! We are indie developers!


This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!

Ethereum

0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy

Bitcoin

3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us on Twitter!

:(