Surgery for adult obstructive sleep apnea (OSA) is still judged by the 1996 Sher criteria — a postoperative apnea-hypopnea index (AHI) below 20 events/hour with at least a 50% reduction — even though a 2024 international expert consensus (35 panelists, Delphi method, 60 statements) agreed these polysomnography-only criteria are 'insufficient and out of date', judged the holistic SLEEP-GOAL score comprehensive but impractical for daily use, and reached consensus that new, precise criteria combining polysomnographic parameters, symptom reduction, and quality-of-life improvement 'should be defined'. No such definition or instrument has been developed and validated: as of 2026, primary studies continue to report Sher-type AHI endpoints, and outcome reporting across prospective neurostimulation studies is documented as heterogeneous. The open problem is to specify an operational, multi-domain definition of surgical success and failure (and a clinically feasible means of applying it) that is anchored to clinically meaningful outcomes — symptoms, quality of life, and end-organ effects — rather than to a single-night AHI count, and to support it with validation evidence that its classifications track those outcomes better than AHI-only criteria do. This is the strand of the 2024 consensus's research agenda that the panel itself identified as the prerequisite; the adjacent evidence-generation strands (comparative salvage-strategy trials, routine-practice measurement of pathophysiological traits, the diagnostic-workup items that did not reach consensus, and durable-response markers) remain separately open.

Background

Obstructive sleep apnea (OSA) is a chronic sleep-related breathing disorder in which the upper airway repeatedly collapses during sleep, causing apneas and hypopneas (partial reductions in airflow), intermittent hypoxia, and sleep fragmentation. Severity is quantified by the apnea-hypopnea index (AHI), the number of apnea plus hypopnea events per hour of sleep, measured by laboratory polysomnography (PSG) or home sleep apnea testing (HSAT). First-line therapy is continuous positive airway pressure (CPAP), a pneumatic splint delivered through a mask; surgery is offered when patients decline, cannot tolerate, or fail CPAP. Surgical options include palatal procedures such as uvulopalatopharyngoplasty (UPPP) and its reconstructive variants (expansion sphincter pharyngoplasty, barbed repositioning pharyngoplasty), tongue-base procedures including transoral robotic surgery (TORS) and midline glossectomy, maxillomandibular advancement (MMA, surgically moving the jaws forward to enlarge the airway), hypoglossal nerve stimulation (HNS, an implanted device that activates the tongue muscles during sleep), and mandibular advancement devices (MAD, dental appliances that protrude the mandible). Since no operation is uniformly effective, the field needs a shared definition of surgical success and failure.

The dominant definition dates to a 1996 meta-analysis by Sher, Schechtman, and Piccirillo, which standardized success as a postoperative AHI below 20 events/hour together with at least a 50% AHI reduction. This 'Sher criteria' benchmark was criticized as early as 2007, when Elshaug and colleagues argued in a meta-analytic synthesis that AHI-only success definitions ignore symptoms, quality of life (QoL), and cardiovascular endpoints, and that AHI itself is unstable (single-night testing, first-night effect). A later physiological framework — PALM, for Pharyngeal Airway collapsibility (quantified by the critical closing pressure, Pcrit), Arousal threshold, Loop gain (the sensitivity of the ventilatory control system, where values above 1 produce self-sustaining oscillations), and Muscle responsiveness — proposed by Eckert and colleagues in 2013, established that OSA has multiple non-anatomical phenotypic causes that a purely anatomical AHI count does not capture. In 2020, Pang and co-workers published SLEEP-GOAL, a multi-endpoint success metric covering cardiovascular and neurocognitive end-organ effects and disease burden, validated on 302 surgically treated patients across nine centers; it reclassified a substantial minority of patients deemed failures by Sher criteria.

The 2024 international expert consensus statement on surgical failure in OSA (Iannella et al., Sleep and Breathing 28(6):2601-2616) was developed by 35 experts through a PRISMA systematic review and a two-round Delphi vote on 60 statements. Of 60 statements, 36 reached consensus and 24 did not. On definition, the panel reached consensus that Sher's criteria 'should be abandoned as they are both insufficient and out of date', that SLEEP-GOAL is holistic and more comprehensive 'but difficult to use everything in daily clinical practice', and that new and precise criteria for surgical success/failure indices 'taking into account polysomnographic parameters, reduction in symptoms and improvement in quality of life, should be defined' — yet half of the definition statements (including which postoperative AHI threshold, symptom persistence, and complication scenarios constitute failure) achieved no consensus. On the diagnostic workup, the panel did reach consensus that drug-induced sleep endoscopy (DISE, fiberoptic endoscopy of the upper airway during pharmacologically induced sleep, used to localize collapse sites) 'should be considered as valid test to identify sites of collapse and obstruction' in patients with PSG-diagnosed surgical failure. The panel additionally flagged further unresolved areas: comparative evidence for salvage strategies after failed surgery; validated, clinically usable measurements of PALM traits in routine practice; several diagnostic-workup items (repeating a postoperative home sleep apnea test before confirming failure, logopedic evaluation for myofunctional therapy, head-and-neck MRI, and going directly to CPAP without further testing); and identification of patient subgroups and markers of durable response.

Problem Statement

Develop and specify an operational, multi-domain definition of surgical success and surgical failure for adult obstructive sleep apnea surgery, together with a clinically feasible means of applying it, that (i) combines objective nocturnal-respiratory indices obtained from standard postoperative testing (polysomnography or home sleep apnea test) with symptom reduction and quality-of-life improvement, as the 2024 international consensus panel agreed new criteria 'should' include; (ii) is usable in routine clinical practice, balancing comprehensiveness with scalability (unlike SLEEP-GOAL, which the panel found too parameter-heavy for daily use); and (iii) is anchored to clinically meaningful postoperative outcomes — symptoms, quality of life, and cardiometabolic or functional endpoints — rather than to a single-night AHI count, so that it improves on the legacy Sher criteria (postoperative AHI below 20 events/hour with at least 50% reduction), which the panel judged insufficient and out of date. The definition should state its domains, how each is measured, and the decision thresholds that separate success from failure, and should be accompanied by a validation plan for surgically treated cohorts — existing cohorts to be reanalysed or prospective cohorts to be recruited — specifying how its success/failure classifications would be shown to correspond to those clinically meaningful outcomes better than AHI-only criteria do; because no validated version of the definition yet exists, the deliverable is this specification and plan, not a completed empirical study. The consensus's companion evidence gaps — which salvage strategy works for which patient subgroup, how to measure PALM physiological traits in routine care, and the diagnostic-workup items on which the panel did not reach consensus — are part of the same research agenda but are distinct evidence-generation problems outside the scope of this problem.

References

  1. Iannella G, Pace A, Magliulo G, Vicini C, Lugo R, Vanderveken OM, de Vries N, Pang K, Thuler E, Jacobowitz O, Cahali MB, Maurer JT, Casale M, Moffa A, Salamanca F, Leone F, Olszewska E, Reina CO, Zancanella E, Hoff PT, Baptista P, Bahgat AY, Ravesloot MJL, van Maanen P, Goldberg A, Carrasco M, Agrawal VK, Lechien JR, De Vito A, Cammaroto G, De Virgilio A, Greco A, Mancini P, Perrone T, Amado S, Alkan U, Cheong RCT, D'Ecclesia A, Galantai D, RajuAnand A, Calvo-Henriquez C, Cocuzza S, Arigliani M, Saibene AM, Aragona RM, Maniaci A (2024) International expert consensus statement: surgical failure in obstructive sleep apnea. Sleep and Breathing 28(6):2601-2616. doi:10.1007/s11325-024-03162-6, https://doi.org/10.1007/s11325-024-03162-6
  2. Sher AE, Schechtman KB, Piccirillo JF (1996) The efficacy of surgical modifications of the upper airway in adults with obstructive sleep apnea syndrome. Sleep 19(2):156-177. doi:10.1093/sleep/19.2.156, https://doi.org/10.1093/sleep/19.2.156
  3. Elshaug AG, Moss JR, Southcott AM, Hiller JE (2007) Redefining success in airway surgery for obstructive sleep apnea: a meta analysis and synthesis of the evidence. Sleep 30(4):461-467. doi:10.1093/sleep/30.4.461, https://doi.org/10.1093/sleep/30.4.461
  4. Pang KP, Baptista PM, Olszewska E, Braverman I, Carrasco-Llatas M, Kishore S, Chandra S, Yang HC, Chan YH, Pang KA, Pang EB, Rotenberg B (2020) SLEEP-GOAL: a multicenter success criteria outcome study on 302 obstructive sleep apnoea (OSA) patients. Medical Journal of Malaysia 75(2):117-123. PubMed PMID 32281591, https://pubmed.ncbi.nlm.nih.gov/32281591/ (no DOI registered)
  5. Eckert DJ, White DP, Jordan AS, Malhotra A, Wellman A (2013) Defining phenotypic causes of obstructive sleep apnea. Identification of novel therapeutic targets. American Journal of Respiratory and Critical Care Medicine 188(8):996-1004. doi:10.1164/rccm.201303-0448OC, https://doi.org/10.1164/rccm.201303-0448OC
  6. Wesson T, Rone V, Ramirez M, Manchanda S, Stahl S, Chernyak Y, Parker N (2024) Outcome reporting in prospective studies evaluating neurostimulation for obstructive sleep apnea. The Laryngoscope 134(12):4873-4881. doi:10.1002/lary.31630, https://doi.org/10.1002/lary.31630
  7. Nassi T, Oppersma E, Donker DW, Westover MB, Thomas RJ (2026) Quantification of ventilatory control in sleep apnea: from physiological insight to computable loop gain. Sleep, zsag155 (online ahead of print). doi:10.1093/sleep/zsag155, https://doi.org/10.1093/sleep/zsag155
  8. Manetti C, Viola B, Danilo C, Carlo BB (2026) Relationship between PALM scale endotypes and surgical outcomes in maxillomandibular advancement for obstructive sleep apnea. Cranio 44(4):788-796. doi:10.1080/08869634.2025.2611150, https://doi.org/10.1080/08869634.2025.2611150
  9. Ling X, Zheng J, Liu Q, Shi C, Fan C (2026) Predictive factors for surgical outcomes and symptom persistence after uvulopalatopharyngoplasty in patients with obstructive sleep apnea. Head & Face Medicine 22(1):52. doi:10.1186/s13005-026-00621-1, https://doi.org/10.1186/s13005-026-00621-1