Title : Cryoneurolysis in restless legs syndrome: A case report of intermediate to long-term relief in 2 patients
Restless Legs Syndrome (RLS) is associated with uncomfortable sensations in limbs that result in a sudden urge to move. The underlying etiology is unknown but is thought to be influenced by genetics, pregnancy, iron deficiency, and alterations in nerve hyperexcitability or inhibition. Current treatment protocols involve variably effective systemic medications often with significant side effects. As a result, non-pharmacological modalities continue to be investigated for the treatment of RLS. This case report demonstrates two patients who achieved intermediate to long-term relief from their RLS symptoms after treatment with ultrasound-guided cryoneurolysis of lower extremity cutaneous nerves. Immediately after treatment, Patient 1 improved her International Restless Legs Syndrome Study Group (IRLSSG) score by 10 points moving her clinical severity from the ‘moderate’ to ‘mild’ range. She reported 95% symptom relief in the treated extremity and 90% relief in the untreated contralateral extremity for 4 months. Long-term symptom relief in the treated lower extremity lasted for 2.5 years until a return to baseline. Patient 2 improved 25 points on the IRLSSG scale immediately after treatment and went from a ‘very severe’ to ‘moderate’ classification. He reported 85-95% symptom relief in the treated extremity and 20% relief in the contralateral extremity for 3 months. Long-term relief in the treated lower extremity continued for a total of 8 months. Bilateral symptom relief despite unilateral treatment coupled with relief of symptoms past return of nerve function in Patient 1 suggest peripheral nerve involvement in the pathogenesis of RLS and the potential for neuromodulation in this disease.
Audience Take Away
- This is the first case report of cryoneurolysis for treatment of restless legs syndrome
- Cryoneurolysis is the only minimally invasive non-pharmacologic treatment for restless legs syndrome that is effective for several months
- This case report expands the realm and clarifies the direction of future restless legs syndrome study of etiology and pathogenesis. Bilateral symptom relief despite unilateral treatment may imply some sort of neuromodulation and interplay of the central and peripheral nervous system in RLS
- There may be additional studies indicated to investigate return of nerve function versus return of RLS symptoms. This case report shows a possible delay in RLS symptoms compared to regrowth of peripheral cutaneous nerves