Temperature controlled radiofrequency ablation for OSA
Ridhwan Y. Baba, M.B.B.S.*1, V.V.S. Ramesh Metta, M.B.B.S.1, Arjun Mohan, M.B.B.S.2, M. Jeffery Mador, M.D.2
1 Department of Internal Medicine, University at Buffalo‐
State University of Buffalo, Buffalo, NY
2 Division of Pulmonary, Critical care and Sleep medicine, Buffalo VA Medical Center, Buffalo, NY
• Conflict of Interest: none
• Financial disclosures: none
Obstructive Sleep Apnea
 Apnea/ hypopnea index > 15 (AASM 1999, Young 1993)
 4% women in USA
 9 % men in USA
 AHI > 5  24% men (Young 1993)
 Obstructive Sleep Apnea Syndrome  2‐4 % adults (Young 1993)
Standard therapy
 CPAP (Sullivan 1981)
 poor tolerance
 CPAP:  20‐23% non compliant (McArdle 1999, Waldhorn 1990)
 Sleepiness: 45%, Hypoxemia: 30%, both 11% (Rolfe 1991)
 MAD:
 Acceptance rate 70% (Mohsenin 2003)
Surgical treatment
LAUP
Mandibular osteotomy & genioglossal
advancement w. hyoid myotomy
Temperature Controlled Radiofrequency Ablation
Radiofrequency ablation
Powell et al, 1999
Recent studies
 Included papers with other surgeries (Nelson et al, 2001‐ UPPP with TCRFTA)
 Socially disruptive snoring (Terris et al, 2002 )
 Grouped patient populations
 Additional studies since 2006
Objective
 Analyze available evidence for efficacy of TCRFTA in OSAS
 polysomnography data
 daytime sleepiness
 quality of life
 Side effects and complications
Methods
Study design
 Systematic review and meta‐analysis (RB, JM)
Included studies
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Randomized controlled trials
Clinical trials
Comparative parallel group trials
Case series Inclusion criteria
 Patient population with  symptoms
 pre‐operative PSG demonstrative of RDI≥ 5  TCRFTA of the soft palate (SP), base of tongue (BoT) or both
 ‘stand‐alone procedure’
Exclusion criteria
 Non‐apneic sleep disorders
 socially disruptive snoring  upper airway resistance syndrome
 sleep disordered breathing  Radiofrequency technology for other interventions eg. uvulopalatoplasty, tonsillectomy Search strategy
 MEDLINE
 EMBASE
 Evidence Based Medicine Reviews Search keywords
 Catheter Ablation
 Diathermy
 Electrocoagulation
 Sleep Apnea Syndrome
 Sleep Apnea, Obstructive  Sleep disordered breathing Limited search to humans
Most recent search: April 2013
Selection process
 Two independent authors (RB, RM)  Reference lists checked for additional citations (did not return in our initial search)  Disagreements resolved either by discussion or by a third reviewer (JM)
Data abstraction
 Self‐developed standardized form
 Second reviewer verified data abstraction Self‐developed standardized form
Analyzed outcomes: Objective
 Polysomnography data:
 Respiratory distress index (RDI)  Lowest oxygen saturation (LSAT, %)  Cephalometric radiography
Analyzed outcomes: Subjective
 Subjective somnolence
 Epworth sleepiness scale (ESS)
 Level of snoring
 Visual analogue scale (VAS, 0 –10) snoring
 OSAS specific quality of life
 Symptoms of Nocturnal Obstruction and Related Events (SNORE25)
 Functional Outcomes of Sleep Questionnaire (FOSQ)
 General health status measured with SF‐36
 Reaction time using the Psychomotor Vigilance Task (PVT‐192; Ambulatory Monitoring Inc, Ardsley, NY)
Methodological features
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Selection bias
Information bias
Matching
Blinding of outcome adjudicator
Adjustment for confounding factors
Confounding variables like prior surgery
Incomplete data
Withdrawals/ loss to follow‐up
Statistical analysis
 RevMan Version 5.2 (Review Manager, Cochrane Collaboration 2012)
 Excel 2011 (Microsoft, Redmond, WA, USA)
Statistical analysis
 RoM = post‐TCRFTA mean/ pre‐TCRFTA mean
 Standard error calculated (Friedrich et al, 2011)
 Standard equations for inverse variance weighting and random effects model (DerSimonian and Laird, 1986)  Heterogeneity (I2) (Higgins 2003)
 0 to 50: low
 50 to 80: moderate and worthy of investigation
 80 to 100: severe and worthy of understanding
 95 to 100: aggregate with major caution  Small number of studies were analyzed in each group, we considered a funnel plot unreliable to determine publication bias (Lau, 2006)
Results
Only abstracts in English:
Guo et al, 2001
Mu et al, 2007 Shao et al, 2008
TCRFTA: Base of tongue
TCRFTA: Base of tongue
Short term follow up (< 12 months)
TCRFTA: Base of tongue (RDI)
TCRFTA: Base of tongue (LSAT)
Excluded studies:
Friedman et al., 2008
TCRFTA: Base of tongue (ESS)
Excluded studies:
Woodson et al, 2001
Friedman et al., 2008
TCRFTA: Base of tongue (VAS snoring)
Excluded studies:
Friedman et al., 2008
TCRFTA: Base of tongue (others)
TCRFTA: Base of tongue
Long term follow up (> 12 months)
TCRFTA: Base of tongue
TCRFTA: Base of tongue
 Adverse events
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ulceration
odynophagia
pharyngodynia
mild‐to‐severe tongue edema
ecchymosis
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hematoma
transient neuralgia
transient tongue deviation
hypoglossal nerve injury
 oral thrush and post‐operative vasovagal reaction were relatively rare complications
 8 cases of infection and 2 cases of tongue base abscess were reported by studies that did not use perioperative antibiotic prophylaxis (Powell et al, 1999, Stuck et al, 2002, Woodson et al, 2001)
TCRFTA: Soft palate
TCRFTA: Soft palate
Excluded studies:
Terris et al, 2002
Atef et al, 2005
Back et al, 2009 TCRFTA: Multi level
TCRFTA: Multi level (RDI1)
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Sub group analysis:
 Randomized vs. non randomized
 Level 1 vs. other PSG  Inclusion/ Exclusion criteria
 Prior surgery or not
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Bipolar vs. unipolar
No of procedures
Baseline AHI
Geography
TCRFTA: Multi level (RDI2)
TCRFTA: Multi level (LSAT2) TCRFTA: Multi level (ESS2)
TCRFTA: Multi level (VAS snoring)
TCRFTA: Multi level TCRFTA: Multi level  Adverse events
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swelling
ulceration
hematoma formation
cellulitis
dysphagia or aspiration
bleeding, and scarring at the surgical site
One unilateral tonsillar abscess formation was also reported (Fischer et al., 2003) Conclusion
 TCRFTA is clinically effective in OSAS
 base of tongue  multilevel procedure
 RDI levels  symptoms of sleepiness in patients  Local anesthesia, low morbidity, transient side effects , comparable efficacy when compared to other surgical treatments
Limitations
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Multiple prior surgery in some studies
Majority observational studies included
Long term follow up limited
Cure rate?
Site of obstruction Surgical protocol variable Identification of OSAS References
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American Academy of Sleep Medicine. International classification of sleep disorders, 2nd Edition: Diagnostic and coding manual. Westchester, IL: American Academy of Sleep Medicine; 2005
Young, T., et al., The occurrence of sleep‐disordered breathing among middle‐aged adults. N Engl J Med, 1993. 328(17): p. 1230‐5.
Sullivan CE, Issa FG, Berthon‐Jones M, Eves L. Reversal of obstructive sleep apnea by continuous positive airway pressure applied through the nares. Lancet 1981;1: 862–
865. McArdle, N., et al., Long‐term Use of CPAP Therapy for Sleep Apnea/Hypopnea Syndrome. J. Am J Respir Crit Care Med 1999. 159:1108–1114. Waldhorn RE, Herrick TW, Nguyen MC, et al. Long‐term compliance with nasal continuous positive airway pressure therapy of obstructive sleep apnea. Chest 1990;97:33–38.
Rolfe I, Olson LG, Saunders NA. Long‐term acceptance of continuous positive airway pressure in obstructive sleep apnea. Am Rev Respir Dis 1991;144:1130–1133. Mohsenin N, Mostofi MT, Mohsenin V. The role of oral appliances in treating obstructive sleep apnea. J Am Dent Assoc 2003;134:442‐9.
References
 Powell, N. B., et al. "Radiofrequency tongue base reduction in sleep‐disordered breathing: A pilot study." Otolaryngology ‐ Head & Neck Surgery 1999. 120(5): 656‐664.
 Farrar, J., et al. "Radiofrequency ablation for the treatment of obstructive sleep apnea: a meta‐analysis." Laryngoscope 2008. 118(10): 1878‐1883.
 Friedrich, J.O., N.K. Adhikari, and J. Beyene, Ratio of means for analyzing continuous outcomes in meta‐analysis performed as well as mean difference methods. J Clin
Epidemiol, 2011. 64(5): 556‐64.  DerSimonian, R. and N. Laird, Meta‐analysis in clinical trials. Control Clin Trials, 1986. 7(3):177‐88.
 Higgins, J.P., et al., Measuring inconsistency in meta‐analyses. BMJ, 2003. 327(7414):557‐60.  Lau, J., et al., The case of the misleading funnel plot. BMJ, 2006. 333(7568):597‐600.