# Radio Frequency



## 574coding (Sep 10, 2015)

Hi,
Would someone be able to explain the difference between the different types of Destructions by Neurolytic Agent or somewhere I can get this info?  I have been searching, but have not found any concrete answers.  

What is pulsed, non-pulsed, cool, thermal, electrical, and chemical destructions?  

Does it depend on the needle or the radiofrequency pulsed generator that was used or the degrees centigrade / Celsius.

I am finding it difficult to extract the type from the documentation.  Should I be coding under the 64600-64681 or using the unlisted code 64999.

Here is a few examples from the report:

Testing for motor stimulation was performed at each level once all the cannulae were in position. Absence of lower extremity motor fasciculation was noted at 4 volts at 2 Hz stimulation during testing of the L3, L4 and  L5 medial branch nerves, respectively. Following this affirmation of negative motor stimulation, negative aspiration for heme or CSF was noted at each level. Next, 1.0 ml of a solution containing 1 mg dexmethasone and 0.25% bupivicaine  was injected at each site. After a 30 second delay, lesions were performed at a temperature of 80 degrees centigrade for a total of 90 seconds. After the needle tips had cooled to 45 degrees centigrade they were sequentially removed  At the end of the procedure it was noted that the patient could purposefully move all four extremities. Sterile bandages were placed over the puncture sites. 

I coded this one under the 62635 and 64636 codes.

and

The patient was placed in the prone position. She was prepped and draped in the usual sterile fashion. A fluoroscopy machine was used to isolate the bony anatomy. The overlying skin was anesthetized with 2 mls of 0.5% Lidocaine at each level. 10 cm radiofrequency needles were advanced under fluoroscopic guidance at each level indicated, to the final position. For the dorsal ramus of L5, the needed tip was placed at the junction of sacral ala and superior articular process of S1. For the lateral branch of S1, S2, and S3, S4 the simplicity catheter was placed in between the foramen and the SIjoint. AP and lateral views confirmed needled placement and needle placement motor testing was begun. Motor interrogation revealed no distal myotomal stimulation. Radiofrequency ablation was initiated at 80 degrees Celsius for 90 seconds. A total of 20mg of Kenalog and 9 cc of .25 Bupivacaine was divided and injected in each level. All needles were withdrawn.

This one I was coding under 64999...

Thank you so much for any help!


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## dwaldman (Sep 15, 2015)

I agree with the way you coded the procedure examples. Below I found information on pulsed radiofrequency that I thought was described the process as it differs from non-pusled radiofrequency. I also was able to find from the same source a description of cooled radiofrequency ablation.

From United Healthcare's medical policy titled Ablative treatment for spinal pain, you can also see how they define the temperature parameters and the time. 

https://www.unitedhealthcareonline....licies/Ablative_Treatment_for_Spinal_Pain.pdf


Thermal radiofrequency ablation of facet joint nerves is proven and medically necessary for chronic cervical, thoracic and lumbar pain when confirmed by: ? Temperature 60 degrees Celsius or more ? Duration of ablation 40 - 90 seconds ? Positive response to medial branch block injection at the side and level of the proposed ablation and ? Confirmation of needle placement by fluoroscopic guided imaging  Thermal radiofrequency ablation is proven and medically necessary:   ? When performed at a frequency of six months or longer (maximum of 2 times over a 12 month period) and ? Provided there has been a 50% or greater documented reduction in pain for 10 to 12 weeks   


http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3059755/


Commercially available RF generators provide PRF signals with pulse durations ranging from 5 to 50 ms and pulse frequency ranging from 1 to 10 Hz, but the most commonly used sequence is a pulse frequency of 2 Hz and a pulse width of 20 ms (Fig. ​(Fig.1)1) [50]. The intrinsic radiofrequency oscillation frequency within each pulse is still about 420 kHz, which is the same as for RF. In PRF, because the pulse duration is only a small percentage of the time between pulses, the average tissue temperature rise for the same RF voltage is much less for PRF than for RF. For instance, using a sequence of 2 Hz ? 20 ms, the power deposition is 4/100 of that during continuous RF for the same voltage. For this reason, higher voltages can be applied to the electrode in PRF than are commonly used in RF without raising the average tissue temperature near the electrode into the denaturation range above 45?C. PRF was initially thought to have no elevated thermal effects, but in vitro experiments have demonstrated the occurrence of brief elevations of temperature??heat spikes? around the needle tip to about 45?C?50?C, depending on the tissue impedance [14]. The magnitude of such spikes has also been shown to reduce significantly with a decrease in the pulse width, for example from 20 to 10 ms [14]. It is, however, not known if these transient ?heat spikes? have an ablative effect.

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Cooled Radiofrequency excert

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3706381/


Cooled radiofrequency denervation

The SInergy? system (Kimberly Clark Health Care, Roswell, GA, USA) is a minimally invasive percutaneous technique that uses internally cooled radiofrequency probes.9 Radiofrequency energy is delivered from and concentrated around the electrode, generating heat in the surrounding tissue. The hollow lumina of the probes permit continuous cooling of the electrode with circulating water. These internally cooled radiofrequency electrodes act as heat sinks that remove heat from tissue adjacent to the electrode. Cooling can lead to larger lesions because it can remove heat from the tissue adjacent to the electrode tip, preventing charring of tissue and maintaining a low impedance to allow dissipation of heat to a larger area.7 As a result, lesions of a larger volume could be produced compared with noncooled electrodes.10,11 By treating a greater area of tissue lateral to the posterior sacral foramina, the chance of disrupting the lateral sacral branches will be higher


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## dwaldman (Sep 16, 2015)

I was reviewing the new 2016 CPT manual, and noticed it stated regarding the temperature:

"Do not report 64633, 64634, 64634, 64635, 64636 for non-thermal joint denervation including chemical, low-grade thermal energy (<80 degree Celsius), or any form of pulsed radiofrequency. To appropriately report any of these modalities, use 64999)."


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## dcepeda (Jul 28, 2020)

When performing a radio frequency neurotomy and no imaging is documented, which code would be utilized to report this procedure?

thank you.


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