Confocal microscopy revisited and dermpath

[coroner]

I recently attended a lecture by Dr. Grant-Kels (Professor of Dermatology, University of Connecticut) who has worked along with Dr. Rabinowitz (Professor of Dermatology, University of Miami) as leading proponents of confocal microscopy for use in clinical dermatology.

There was a thread about this 5 years ago: confocal microscopy and future of biopsies But, that pertained more to endoscopy. I thought this lecture presented interesting applications towards dermatology. Here's the highlights:

PROS (from dermatologist/dermpath point of view)

• Non-invasive procedure which can reduce skin biopsies by 60%
• Meetings have already taken place with RUC and CMS for coding/fee scheduling with PC evaluated at $45 i.e. slightly higher than vs current rate of $39 for an 88305 (Procedural rate is also similar to that of performing a bx)
  
• Sensitivity of ~90% and Specificity of 70%.
• Already in use at certain academic centers e.g. Northwestern, UConn, The "U", Georgetown, etc. And being taught to derm residents as well as published in their blue journal which means it can be fair game to show up on their boards.
  
• Dermatologists can make dx. based on en-vivo scanning
• Scanner produces digital images which can be beamed to consultant for interpretation. Therefore, with potential to work remotely.

CONS

• Imaging only penetrates to superficial reticular dermis.
• Sensitivity & Specificity still inferior to conventional H&E.
  
• Final stages of approval for billing/coding still pending due to bureaucrats wanting their piece of the pie.
• Cost of instrument is roughly $50,000 - $100,000.
  
• Not commonplace yet. As mentioned, primarily in large academic centers currently. Therefore, providers in Texarkana, AR probably won't be doing confocal microscopy anytime soon.
• Limited number of experts in the field qualified to give dx. (growing with exposure to trainees)
  
• Time for scanning takes 20 min. for a single lesion. But, the machine is tech operated. So while the scan is taking place in clinic, the dermatologist can see other pts.

A key point mentioned was that if confocal microscopy is the future, then the reduced rate of bxs. won't necessarily be bad for dermatology/dermpath business, because it will be offset by the increase in en-vivo microscopy and dermatologists and dermpaths because will still be the ones interpreting it. She did express caution that general pathologists or even radiologists may try and capture potential market share for interpretation. But, my take is that it shouldn't be an issue, because if the provider doesn't interpret it themselves, they will continue to send it to someone else who can, whether it's a dermpath or general path. No different than where skin bxs. are sent.

As mentioned, there was a previous thread on here, but I thought this topic deserved revisiting as it has gained some traction. Anyone have further insight or think differently now?

---

Members don't see this ad.

 

[AZpath]

I recently attended a lecture by Dr. Grant-Kels (Professor of Dermatology, University of Connecticut) who has worked along with Dr. Rabinowitz (Professor of Dermatology, University of Miami) as leading proponents of confocal microscopy for use in clinical dermatology.

There was a thread about this 5 years ago: confocal microscopy and future of biopsies But, that pertained more to endoscopy. I thought this lecture presented interesting applications towards dermatology. Here's the highlights:

PROS (from dermatologist/dermpath point of view)

• Non-invasive procedure which can reduce skin biopsies by 60%
• Meetings have already taken place with RUC and CMS for coding/fee scheduling with PC evaluated at $45 i.e. slightly higher than vs current rate of $39 for an 88305 (Procedural rate is also similar to that of performing a bx)
  
• Sensitivity of ~90% and Specificity of 70%.
• Already in use at certain academic centers e.g. Northwestern, UConn, The "U", Georgetown, etc. And being taught to derm residents as well as published in their blue journal which means it can be fair game to show up on their boards.
  
• Dermatologists can make dx. based on en-vivo scanning
• Scanner produces digital images which can be beamed to consultant for interpretation. Therefore, with potential to work remotely.

CONS

• Imaging only penetrates to superficial reticular dermis.
• Sensitivity & Specificity still inferior to conventional H&E.
  
• Final stages of approval for billing/coding still pending due to bureaucrats wanting their piece of the pie.
• Cost of instrument is roughly $50,000 - $100,000.
  
• Not commonplace yet. As mentioned, primarily in large academic centers currently. Therefore, providers in Texarkana, AR probably won't be doing confocal microscopy anytime soon.
• Limited number of experts in the field qualified to give dx. (growing with exposure to trainees)
  
• Time for scanning takes 20 min. for a single lesion. But, the machine is tech operated. So while the scan is taking place in clinic, the dermatologist can see other pts.

A key point mentioned was that if confocal microscopy is the future, then the reduced rate of bxs. won't necessarily be bad for dermatology/dermpath business, because it will be offset by the increase in en-vivo microscopy and dermatologists and dermpaths because will still be the ones interpreting it. She did express caution that general pathologists or even radiologists may try and capture potential market share for interpretation. But, my take is that it shouldn't be an issue, because if the provider doesn't interpret it themselves, they will continue to send it to someone else who can, whether it's a dermpath or general path. No different than where skin bxs. are sent.

As mentioned, there was a previous thread on here, but I thought this topic deserved revisiting as it has gained some traction. Anyone have further insight or think differently now?

 

[AZpath]

Do derms want to interpret the images themselves?
It depend on the pitfalls

 

[Mace1370]

Do derms want to interpret the images themselves?
It depend on the pitfalls

At this point in the game, my impression is that they generally don't. However, derm residents seem to go where the money is. It will be interesting to see what happens. Will training for this be lumped in with dermpath fellowships? Will it be a separate fellowship on its own?

 

[tiredguy]

• Sensitivity of ~90% and Specificity of 70%.

Is this good enough to skip a biopsy and send the patient back out on the street?

 

[coroner]

Do derms want to interpret the images themselves?
It depend on the pitfalls

My impression was no more than they would want to interpret a skin bx (unless they trained in dermpath). Yes it reimburses more, but only by about 6 bucks. I would think they''d rather see more patients and/or do more procedures which pays more.

Is this good enough to skip a biopsy and send the patient back out on the street?

Most of the decision process would be pre-test with a comprehensive approach. For example there's clinical evaluation/impression of a lesion, then they can use a dermascope, and finally a confocal microscope. The combined method may add to that a bit. Essentially, it comes down to the clinician's judgement if they feel confident in letting the patient "walk" without a bx. And, it would be up to them to determine if the above still doesn't lead to adequate diagnostic uncertainty to perform the bx.

 

[AZpath]

Easier to add a dermpath and lab to the practice.
I would be very surprised if it really takes off. They lose the surgical procedure and tie up room for waiting for the tech.

I though confocal would takeoff in GI too. For GI one Problem is that it takes a few extra minutes to evaluate the polyps.
That's a pain to most GIs.
If they rush it the quality goes to zip.

 

[coroner]

They lose the surgical procedure and tie up room for waiting for the tech.

No, they don't. I didn't mention this earlier but the procedural reimbursement is $105 which is the same as doing the bx. However, the time cost (as mentioned earlier) is significant at 20 min. Much quicker to do a shave bx. which pays the same. On the other hand, they wouldn't lose time doing the scan as the MA can do it vs a bx

 

[tensoranalysis]

what spectrum of light are they using? It would be nice if there was a non-toxic dye available to increase contrast and possibly make this technology amenable to two-photon.

If you puckered the skin, maybe you could use single plane imaging (light sheet) imaging to acquire images faster. Gathering reflected light is a limiting factor - maybe using more of the IR spectrum can alleviate some of this.

I see movement being a huge practical limitation. I'm sure there are computational stabilization methods available.