Robot-assisted Tongue Base Resection ensures favorable therapeutic outcome to Obstructive Sleep Apnea patients with Lingual tonsil hypertrophy

Abstract

Tongue base (TB) narrowing is recognized as a significant site of upper airway collapse during sleep in obstructive sleep apnea (OSA) patients and robot technology is expected to have promising clinical utility in OSA patients with TB narrowing. The purpose of our study is to demonstrate the better therapeutic conditions and favorable indications of robot-assisted TB resection (TBR) in OSA. We performed robot-assisted TBR combined with nasal and palatal surgery in 16 OSA patients with any of the following characteristics: severe TB narrowing (over grade II) and moderate or severe OSA. The preoperative median AHI was 48.8/hr and the median lowest SaO₂ was 82.0%. The median AHI decreased to 18.7/hr and ten patients (62.5%) were included in the responder group following robot-assisted TBR combined with nasal and palatal surgery. The lowest SaO₂ improved to 90.5% and the posterior airway space (PAS) was significantly increased following robot-assisted TBR. Cephalometric results showed that wider PAS were observed in responders compared to non-responders prior to robot-assisted TBR. Interestingly, there was greater improvement in the objective parameters including PAS in the OSA patients with lingual tonsilar hypertrophy than they were in those without and all patients with lingual tonsillar hypertrophy (n = 6) responded to robot-assisted TBR. Robot-assisted TBR exhibited minimal morbidity and postoperative complications in OSA patients. Robot-assisted TBR can be considered a promising and innovative surgical option to reduce TB volume and improve sleep parameters in OSA patients with TB narrowing. OSA patient with TB narrowing due to lingual tonsil hypertrophy shows greater therapeutic outcome and lingual tonsil hypertrophy appears to be most favorable surgical indications of robot-assisted TBR.

Figure 1

The surgical indications for robot-assisted TBR. (A) 30° endoscopic findings of lingual tonsil hypertrophy. (B) Cephalographic measurement for retrognathia (S: sella, N: nasion, B: infradental) (C) 30° endoscopic findings of remained TB lymphoid tissue in OSA patients with previous TB surgery. (D) Inclusion criteria for robot-assisted TBR in the present study. Bars represent the number of subjects.

Figure 2

Schematic of the study design and clinical evaluation. (TBR: tongue base resection, PSG: polysomnogram, DISE: drug-induced sleep endoscopy).

Figure 3

The surgical field of the robot-assisted TBR under da Vinci Xi.

Figure 4

Changes in subjective symptoms of OSA patients following robot-assisted TBR. Improvement in subjective symptoms such as breathing, snoring volume, and sleep quality were determined using the visual analogue scale questionnaire.

Figure 5

Subjective complaints and side effects one month and three months following robot-assisted TBR. Bars represent the number of subjects.