This prospective, interventional, non-randomized, single arm, clinical trial will investigate feasibility and safety of trans-oral robotic surgery using da Vinci SP Surgical System in Taiwan for the surgical treatment of OSA. All the investigators are well trained and have received proof of training after completing the training program for da Vinci SP system provided by Intuitive.

This study will be conducted in Chang Gung Memorial Hospital at Linkou.

Informed consent will be provided to patient who has an indication of surgical treatment for OSA. Study participants will sign an informed consent before any study procedure begins. Eligibilities will be assessed during screening period (2 weeks) with blood test and other routine assessments. Eligible patient will undergo surgical intervention using da Vinci SP Surgical System. Post-operation follow-up will be performed at 1 week, 1 month, 3 months, and 6 months.

Inclusion Criteria:

1. Age 18 years or more.
2. OSA with AHI ≥ 15
3. Has failed, refuses, or is unable to tolerate CPAP therapy
4. Indication of resection of tongue base with/without other invasive surgical procedure for OSA (i.e. tongue base resection only or multi-level surgery with tongue base resection)
5. ASA physical status classification 1-2 and adequate organ function
6. Patients willing and able to comply with study protocol requirements and follow-up
7. Informed consent

Exclusion Criteria:

1. BMI>35

2. Mouth opening too narrow for TORS or trismus

3. Betel nut chewing

4. Suspicious cancer diagnosis

5. Prior head-and-neck surgery (note: prior invasive therapy for OSA allowed)

6. Other medical condition or anatomical factor not suitable for TORS, including subject with congenital malformations in the larynx, throat or tongue; 1. Subject with an American Society of Anesthesiologists (ASA) score of Grade 4 or above during preoperative evaluation

7. Active infectious disease

8. Can't follow trial-required procedures

9. Severe concomitant illness that drastically shortens life expectancy or increases risk of therapeutic interventions

   • Severe heart disease (NYHA functional class III-IV)
   • Severe lung disease (GOLD Group C-D)

10. Long-term use of anti-coagulant

11. Patients with coagulopathy

12. Emergency surgery

13. Subject for whom any additional surgeries are planned for OSA within the study period, after the surgery in which the da Vinci SP System was used

14. Subject is pregnant or suspected to be pregnant