Hypoglossal nerve stimulation (HNS) is reasonable and necessary for the
treatment of moderate to severe obstructive sleep apnea (OSA) when **__all__**
of the following criteria are met:

  1. Beneficiary is 22 years of age or older; **and**
  2. Body mass index (BMI) is less than 35 kg/m2; **and**
  3. A polysomnography (PSG) demonstrating an apnea-hypopnea index (AHI) of 15 to 65 events per hour within 24 months of initial consultation for HNS implant; **and**
  4. Beneficiary has predominantly obstructive events (defined as central and mixed apneas less than 25% of the total AHI); **and**
  5. Shared Decision-Making (SDM) between the Beneficiary, Sleep physician, AND qualified otolaryngologist (if they are not the same) who determines that the Beneficiary demonstrates continuous positive airway pressure (CPAP) failure (defined as AHI greater than 15 despite CPAP usage) or CPAP intolerance (defined as CPAP machine-derived compliance reporting with usage less than 4 hours a night for at least 70% of the nights in 1 month, or the CPAP has been returned) despite CPAP interface and/or setting optimizations.
  6. Confirmed absence of complete concentric collapse at the soft palate level by a drug-induced sleep endoscopy (DISE) procedure; **and**
  7. Absence of anatomical findings that would compromise performance of device (e.g., tonsil size 3 or 4 per standardized tonsillar hypertrophy grading scale).
  8. Use of HNS devices with United States (U.S.) Food and Drug Administration (FDA)-approval for implantation to treat OSA (e.g.,[ Inspire II Upper Airway Stimulator](https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpma/pma.cfm?id=P130008)). 

HNS is not reasonable or necessary when any 1 of the following
contraindications are present:

  * Beneficiaries with central and mixed apneas that make up more than one-quarter of the total AHI
  * BMI 35 kg/m2 or greater
  * Neuromuscular disease
  * Hypoglossal-nerve palsy
  * Severe restrictive or obstructive pulmonary disease
  * Moderate-to-severe pulmonary arterial hypertension
  * Severe valvular heart disease
  * New York Heart Association class III or IV heart failure
  * Recent myocardial infarction or severe cardiac arrhythmias (within the past 6 months)
  * Persistent uncontrolled hypertension despite medication use
  * Acute psychiatric disease
  * Coexisting non-respiratory sleep disorders that would confound functional sleep assessment
  * Beneficiaries who are, or who plan to become pregnant
  * Beneficiaries who are unable or do not have the necessary assistance to operate the device's external programmer
  * Beneficiaries with any condition or procedure that has compromised neurological control of the upper airway
  * HNS implant devices that are not compatible with magnetic resonance imaging (MRI) in Beneficiaries who require MRI

**NOTE:** Beneficiaries with certain HNS devices can undergo MRI of the head
and extremities if certain conditions and precautions are met. Please refer to
the Manufacturer Guidelines for the relevant model for more information.

**Credentialing and Accreditation Standards**

Provider Qualifications for HNS Implantation and Device Management

Optimal outcomes of HNS implantation procedures depend on the knowledge, skill
and experience of the provider(s). Consequently, the qualified provider
performing the procedure must be capable of demonstrating documented training
and experience relevant to HNS implantation.

HNS-implantation services will only be considered reasonable and necessary if
provided in facilities with standards of medical practice and personnel
appropriate for the patient's medical needs, risk of adverse events, and when
performed by qualified providers with all of the following:

  * All HNS implantation procedures must be performed by a licensed qualified physician

  * A licensed qualified physician (MD or DO) for HNS services is defined as:

    * Having trained and acquired expertise within the framework of an accredited residency **or** fellowship program in the applicable specialty/subspecialty (e.g., Board-eligible (BE) or Board-certified (BC) otolaryngologist) **or** must reflect equivalent education, training and expertise endorsed by a relevant specialty/subspecialty society, **and**

    * Prior to implanting the system, surgeons will have received education and proctoring by an FDA-approved device manufacturer or equivalent proctoring body on device implant techniques, including cadaver training. Documentation must be available for contractor review to provide confirmation of proficiency in the performance and management of HNS implantation and the corresponding relevant devices.

  * The provider performing DISE shall be certified by the FDA-approved manufacturer's second opinion service of validation via video clip submissions of at least 80% agreement in at least 15 consecutive studies. Documentation of this proficiency must be available to submit for contractor review.

Excluding routine post-op care by the implanting surgeon (e.g., initial
empiric programming), initial consultation and post-implant evaluation and
management of Beneficiaries appropriate for HSN devices must be performed by
BE or BC Sleep physicians with qualifications as outlined in LCD L36593
[Polysomnography] and Article A55958 [Accreditation and Credentialing
Requirements for Polysomnography LCD L36593]. Additionally, sleep studies
shall be performed by an accredited sleep facility as stated in LCD L36593.
Please refer to the Article A55958 regarding Independent Diagnostic Testing
Facility (IDTF) for additional information. BC/BE Sleep physicians must
complete HNS device education and training (including hands-on operation of
the external programmer) by an FDA-approved device manufacturer or equivalent
proctoring body.

OSA is a common, chronic disorder characterized by recurrent narrowing and/or
closure of the upper airway accompanied by intermittent oxyhemoglobin
desaturation, arousal from sleep and sympathetic activation.1,2 Sequelae
include disturbed sleep, excessive sleepiness and impaired quality of life
(QOL). Moderate-to-severe OSA, defined as an AHI score of 15 or more
apnea/hypopnea events per hour, is an independent risk factor for insulin
resistance, dyslipidemia, vascular disease, and death.3-7 Treatment with CPAP
improves disturbed sleep; however, the general effectiveness of CPAP therapy
is dependent on patient acceptance of and adherence to the treatment.8,9 There
are no effective options for patients with moderate-to-severe OSA for whom
CPAP is ineffective or intolerant.

**HNS has demonstrated safety and efficacy**

Stimulation of the hypoglossal nerve that innervates the genioglossus is now a
new therapeutic option for moderate and severe cases of obstructive sleep
apnea-hypopnea syndrome (OSAHS). Two types of stimulation are currently
available: (a) stimulation synchronous with inspiration and (b) continuous
stimulation. Delgado, et al. concluded that indication of each type of
stimulation and long-term effects still need to be assessed, but the
implantable nerve stimulation is a promising treatment for patients without a
therapy solution so far.10 In a multi-center, prospective, cohort study,
Gillespie, et al. (2017) evaluated patient-based outcomes of subjects in a
large cohort study (the Stimulation Therapy for Apnea Reduction [STAR] trial)
48 months after implantation with an upper airway stimulation (UAS) system for
moderate-to-severe OSA. Patients (n = 91) at 48 months from a cohort of 126
implanted participants were included in this analysis.11 A total of 126
subjects received an implanted UAS system in a prospective phase III clinical
trial. Patient-reported outcomes at 48 months, including Epworth Sleepiness
Scale (ESS), Functional Outcomes of Sleep Questionnaire (FOSQ), and snoring
level, were compared with pre-implantation baseline. A total of 91 subjects
completed the 48-month visit. Daytime sleepiness as measured by ESS was
significantly reduced (p = 0.01), and sleep-related QOL as measured by FOSQ
significantly improved (p = 0.01) when compared with baseline. Soft to no
snoring was reported by 85% of bed partners; 2 patients needed additional
surgery without complication for lead malfunction. The authors concluded that
UAS maintained a sustained benefit on patient-reported outcomes (ESS, FOSQ,
snoring) at 48 months in select patients with moderate-to-severe OSA. The
authors stated that the main drawback of this study was the increased number
of patients lost to follow-up at 48 months compared with 36 months (25 versus
4). Factors that influence adherence to follow-up include individual patient
characteristics, social support, medical staff characteristics, and research
study design. The trend of older age for those who completed follow-up versus
those lost at 48 months was consistent with other trials that have noted
poorer follow-up in younger cohorts, perhaps due to increased demands of work-
life balance among younger subjects. With regard to medical staff, loss of a
principal investigator and study-site support accounted for 20% of follow-up
loss at 48 months. This trial, like many other multi-year trials, experienced
greater loss of follow-up after 3 years. They noted that ongoing follow-up is
needed to determine the natural product life of the device components.

In a prospective, multi-center, single-arm study, Steffen, et al. (2018)
reported objective and patient-reported outcome after 12 months of
implantation. Consecutive patients who received the UAS system (Inspire
Medical Systems, Inc., Minneapolis, MN) were enrolled in 3 German centers.12
Key study exclusion criteria included BMI greater than 35 kg/m2, AHI less than
15 or greater than 65, or complete concentric collapse at the soft palate
during sedated endoscopy. Data collection at 6- and 12- month visit include
home sleep test and patient-reported outcome measures. Among the total of 60
participants, the median AHI reduced from 28.6 to 9.5 from baseline to 12
months. Patient-reported outcome measured in ESS and FOSQ both improved
significantly from baseline to 12 months. The average usage time was 39.1 
14.9 hours per week among all participants based on recordings by the
implanted device; 1 patient requested a removal of the device for cosmetic and
other personal reasons and was completed without sequelae. The authors
concluded that the findings of this study supported that UAS is a safe and
effective therapeutic option for patients with OSA in routine clinical
practice. However, the level of evidence was limited (IV) as this was an
uncontrolled study with relatively small study with short-term follow-up.

Hofauer, et al. (2017) conducted a prospective cohort study to compare changes
in sleep architecture during the diagnostic PSG and the post-implantation PSG
in UAS in patients with OSA.13 The study included 26 patients who received a
UAS device (Inspire Medical Systems). Treatment outcome was evaluated 2 and 3
months after surgery. Data collection included demographics, BMI, AHI, oxygen
saturation and desaturation index (ODI), ESS, arousal parameter, and sleep
patterns. The mean age was 60.2 years, 25 patients were male, 1 patient was
female. Mean BMI was 29.0 kg/m2. The mean pre-implantation AHI of 33.9/h could
be reduced to 9.1/h at 2 months post-implantation (p < 0.001). The amount of
time spent in N1-sleep could be reduced from 23.2% at baseline to 16.0% at
month 3 post-implantation. The amount of time spent in N2- and N3-sleep did
not change during the observation period. A significant increase of the amount
of rapid-eye-movement (REM) sleep at month 2 (15.7%) compared to baseline
(9.5%; p = 0.010) could be observed. A reduction of the number of arousals and
the arousal index could be observed. The authors concluded that significant
changes in sleep architecture of patients with OSA and sufficient treatment
with UAS could be observed. A reduction of the amount of time spent in
N1-sleep could be caused by treatment with UAS and the rebound of REM sleep,
observed for the first time in a study on UAS, is also a potential marker of
the efficacy of UAS on sleep architecture.

Huntley, et al. (2017) conducted a retrospective study to compare UAS for the
treatment of OSA at 2 academic centers between May 2014 and August 2016.14 The
investigators recorded demographic data, ESS, and preoperative and
postoperative polysomnographic information. They compared outcome data between
institutions and subsequently combined the cohorts and compared baseline to
posttreatment results. Cohort 1 consisted of 30 males and 18 females with mean
BMI of 29.3 kg/m2. The mean preoperative AHI, O2 nadir, and ESS were 35.88,
80.96, and 11.09, respectively. The mean postoperative AHI, O2 nadir, and ESS
were 6.34, 88.04, and 5.77, respectively. Cohort 2 consisted of 30 males and
19 females with a mean BMI of 27.7 kg/m2. The mean preoperative AHI, O2 nadir,
and ESS were 35.29, 79.58, and 10.94, respectively. The mean postoperative
AHI, O2 nadir, and ESS were 6.28, 84.35, and 6.60, respectively. The
investigators found no difference in patients reaching a postoperative AHI
less than 15, 10, and 5 when comparing the cohorts. After combining cohorts,
they found a significant improvement in postoperative AHI, O2 nadir, and ESS
compared to preoperative values. Huntley and colleagues concluded that UAS
appears to provide a viable alternative to CPAP, producing improvement in both
polysomnographic and QOL measures. The study established that results are
reproducible at high-volume centers.

The position statement from the American Academy of Otolaryngology (AAO)
(2016) states that:

"The AAO considers upper airway stimulation (UAS) via the hypoglossal nerve
for the treatment of adult obstructive sleep apnea syndrome to be an effective
second-line treatment of moderate to severe obstructive sleep apnea in
patients who are intolerant or unable to achieve benefit with positive
pressure therapy (PAP). Not all adult patients are candidates for UAS therapy
and appropriate polysomnographic, age, BMI and objective upper airway
evaluation measures are required for proper patient selection."

**FDA eligibility criteria for HNS implantation**

The Inspire UAS (Inspire Medical Systems, Inc.) is an FDA-approved implanted
upper airway stimulator that includes an implantable pulse generator and leads
system, and external programmer indicated for second-line treatment of adult
patients with moderate-to-severe OSA. The system delivers mild stimulation to
the hypoglossal nerve which controls the movement of the tongue and other key
airway muscles. By stimulating these muscles, the airway remains open during
sleep. The FDA eligibility criteria for the UAS implantation include age 22
years of age and older, moderate or severe OSA (defined as AHI 20 to 65
events/hour), predominantly obstructive events (defined as central and mixed
apneas less than 25% of the total AHI), CPAP failure (defined as AHI >20 on
CPAP) or intolerance (defined as use <4 hours per night, 5 nights per week; or
unwillingness to use), no complete concentric velopharyngeal collapse on
screening sleep endoscopy, and no other anatomical findings that would
compromise performance of the device (e.g., tonsil size 3 or 4). It is not
recommended for patients with BMI >32 kg/m2 (FDA, 2014; Inspire Medical
Systems, 2014; UpToDate, 2017). Patients who are pregnant or plan to become
pregnant, are unable or do not have the necessary assistance to operate the
sleep remote, will require MRI (excluding Inspire 3028 system which has MRI
labeling), or any condition or procedure that has compromised neurological
control of the upper airway, are considered contraindications for hypoglossal
nerve UAS implantation (FDA, 2014). Per Inspire Medical Systems, having a
cardiac pacemaker is not a contraindication for the Inspire device. In March
2017, the FDA approved to expand the AHI range from 20-65, to 15-65
events/hour (FDA, 2017).

In June 2017, Inspire Medical Systems, Inc. announced the FDA approval for
the next-generation device, Inspire 3028 implantable pulse generator, which
includes magnetic resonance (MR) conditional labeling to allow patients to
undergo MRI safely. The Inspire 3028 device is 40% smaller and 18% thinner
than the current Inspire neurostimulator which received FDA approval in April
2014. Patients can undergo MRI on the head and extremities if certain
conditions and precautions are met (Inspire Medical Systems, 2017).
Additionally, the AHI range was extended from 20-65 events/hour to 15-65
events/hour.

**HNS long-term safety and efficacy demonstrated**

Woodson, et al. (2018) evaluated 5-year outcomes of UAS from a multicenter
prospective cohort study of 126 patients with OSA who were treated with UAS
via a unilateral hypoglossal nerve implant.15 Those having CPAP failure with
moderate-to-severe OSA, BMI <32 kg/m2, and no unfavorable collapse on DISE
were enrolled in the phase 3 trial. Outcomes evaluated included AHI, ODI, and
adverse events, as well as measures of sleepiness, QOL, and snoring.
Improvement in ESS and QOL was observed, with normalization of scores
increasing from 33% to 78% and 15% to 67%, respectively. AHI response rate
(AHI <20 events/hour and >50% reduction) was 75% (n = 71). "When a last
observation carried forward analysis was applied, the responder rate was 63%
at 5 years. Serious device-related events all related to lead/device
adjustments were reported in 6% of patients." The authors concluded that
improvements in sleepiness, QOL, and respiratory outcomes were observed with 5
years of UAS. Serious adverse events were uncommon. The authors reported that
"UAS is a non-anatomic surgical treatment with long-term benefit for
individuals with moderate to severe OSA who have failed nasal CPAP."

**Drug Induced Sleep Endoscopy (DISE)**

There is evidence of moderate limitations in inter-rater reliability for
determining if complete concentric collapse (CCC) is present during DISE.16 To
reduce variation in patient selection and optimize outcomes, a second-opinion
to confirm DISE reporting is recommended.

**Shared Decision-Making**

SDM incorporates the patient's values and preferences into medical decisions
and puts the patient at the center of care. Studies suggest that patient-
provider communication about nontechnical aspects of care improves patient
satisfaction and positively affects health outcomes.17-19

Level of evidence - Good (I-IIb, with risks of bias)

Strength of recommendation - Good

Based on the best available evidence, selected patients who have symptoms and
signs of moderate-to-severe OSA and demonstrate either CPAP failure or
intolerance are appropriate candidates for HNS. A critical mass of level I-IIb
evidence, including data with FDA-approved devices at multiple sites with
short-, mid-, and long-term follow up and specialty society endorsement is
compelling enough to consider HNS as a reasonable option for surgical
treatment of OSA in select patients. The evidence is sufficient to determine
that the technology results in meaningful improvements in the net health
outcome.