Stanley Liu

Stanley Liu
Stanford University | SU · Department of Otolaryngology

MD DDS FACS
Looking for collaboration in AI/ ML

About

107
Publications
44,272
Reads
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1,523
Citations
Introduction
I am an Associate Professor of Otolaryngology in the Division of Sleep Surgery, and direct the Stanford Sleep Surgery Fellowship. I am a former Stanford Biodesign Faculty Fellow (2018).
Additional affiliations
October 2021 - present
Stanford Medicine
Position
  • Professor (Associate)
September 2014 - September 2021
Stanford Medicine
Position
  • Professor (Assistant)
Education
August 2007 - May 2011
July 2002 - June 2007
September 1996 - June 2000
Stanford University
Field of study
  • Biology

Publications

Publications (107)
Article
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Objectives: Using sleep MRI, we aimed to identify static craniofacial measurements and dynamic upper airway collapse patterns associated with severe obstructive sleep apnea (OSA) during natural sleep in age and BMI matched patients. Design: Nested case-control study. Setting: Sleep MRI images (3.0 Tesla scanner) and synchronized acoustic recor...
Article
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Objectives To use drug-induced sedation endoscopy (DISE) and computational fluid dynamics (CFD) modeling to study dynamic airway and airflow changes after maxillomandibular advancement (MMA), and how the changes correlate with surgical success based on polysomnography parameters. Study Design Retrospective cohort study. Setting University medical...
Article
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A narrow maxilla with high arched palate characterizes a phenotype of obstructive sleep apnea (OSA) patients that is associated with increased nasal resistance and posterior tongue displacement. Current maxillary expansion techniques for adults are designed to correct dentofacial deformity. We describe distraction osteogenesis maxillary expansion (...
Article
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Objective: To determine if a modified tissue-preserving palatopharyngoplasty could convert retropalatal concentric collapse to anteroposterior or lateral patterns of collapse on drug-induced sleep endoscopy (DISE) in patients who are not candidates for upper airway stimulation due to complete circumferential collapse at the velum. Methods: A pro...
Article
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PurposeThe aim of this study was to investigate the correlation between the changes in respiratory function and dimensions of the nasomaxillary complex (NMC) and upper airway (UA) compartments after nasomaxillary skeletal expansion (NMSE) treatment for pediatric patients with obstructive sleep apnea (OSA).Methods Nonobese OSA patients (mean age, 13...
Article
Introduction With recognized anatomic and physiological differences between males and females, it is critical to describe outcomes of sleep surgery with respect to gender. The objective of this study is to compare the subjective and objective outcomes of phase I sleep surgery with respect to gender and age. Methods This was a retrospective review...
Article
Introduction Anatomic characterization of the upper airway remains important in directing and monitoring care of patients with obstructive sleep apnea (OSA). Nasopharyngoscopy is routine in clinical practice, but it is invasive, non-reproducible, and only allows subjective assessment. We used machine-learning enabled ultrasonography to correlate up...
Article
Obstructive sleep apnea (OSA) is characterized by partial or complete airway blockage during sleep. Nocturnal nasal obstruction usually leads to mouth breathing while sleeping, which worsens sleep apnea by aggravating tongue base and lateral pharyngeal wall collapse. The pathogenesis of OSA is multifactorial, and the precipitating factors vary sign...
Article
Background: Patients with narrow high-arch palate present with limited response to standard septal, turbinate, and valve procedures for nasal obstruction. Objective: To measure the effectiveness of minimally invasive nasal endoscopic (MINE) Lefort I osteotomy among subjects with narrow high-arched palate in managing nasal obstruction. Methods: Pros...
Article
Introduction Adenoid and tonsillar hypertrophy in children often leads to adverse respiratory symptoms and obstructive sleep apnea (OSA). Current clinical guidelines from the American Academy of Pediatrics and American Academy of Otolaryngology–Head and Neck Surgery recommend tonsillectomy as the first line of pediatric OSA treatment for children w...
Article
Background : Distraction osteogenesis maxillary expansion (DOME) is an emerging surgical concept for obstructive sleep apnea patients presenting with nasal obstruction, with a high-arched and narrow hard palate. We demonstrate the feasibility of DOME in the treatment of patients with persistent nasal obstruction after primary septoplasty. Methods...
Article
Background: Rate of corrective nasal surgery after maxillomandibular advancement (MMA) for obstructive sleep apnea (OSA) has been reported to be 18.7% for functional and aesthetic indications. Objective: Describe a comprehensive strategy to optimize nasal outcomes with MMA for OSA. Methods: A retrospective review of patients undergoing MMA for OSA...
Article
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This article investigates the effects of continuous positive airway pressure (CPAP) on hearing impairment in sensorineural hearing loss (SNHL) patients with sleep-disordered breathing (SDB). This retrospective and observational study took place from September 2016 to February 2021, accumulating 77 subjects with SNHL and SDB (60.7 ± 11.1 years). Of...
Article
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Objective: The aim of this study is to evaluate the impact of rapid palatal expansion (RPE) on the nasal airway subjectively by utilizing patient-reported outcome measures (PROM) and objectively by evaluating validated internal nasal valve (INV) measurements obtained from cone beam computed tomography (CBCT) in pediatrics. Materials and methods:...
Article
Obstructive sleep apnea (OSA) is characterized by decreased breathing events that occur through the night, with severity reported as the apnea-hypopnea index (AHI), which is associated with certain craniofacial features. In this study, we used data from 1366 patients collected as part of Stanford Technology Analytics and Genomics in Sleep (STAGES)...
Article
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(1) Background: Sleep apnea may be a risk factor for deep neck infection (DNI). The objective of this study was to investigate the effects of sleep apnea on DNI. (2) Methods: In this first nationwide retrospective cohort study on the sleep apnea–DNI correlation, we obtained data from the Longitudinal Health Insurance Database 2005, a subset of the...
Article
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PurposePrevious studies focusing on phenotyping obstructive sleep apnea (OSA) have outlined its heterogeneity in clinical symptoms, comorbidities, and polysomnographic features. However, the role of anatomical or pathophysiological causality including craniofacial skeletal deformity has not been studied. We aimed to identify and characterize phenot...
Article
Purpose Becoming an oral-maxillofacial surgeon (OMS) is often challenging for young trainees. The purpose of this manuscript is to explore how a student-led group, which emphasizes networking, mentorship, and academic opportunities, may impact one’s journey to becoming an OMS. Methods This was a cross-sectional descriptive study where a 5-question...
Chapter
Transverse maxillary deficiency is one of several common craniofacial structure characteristics observed in patients with obstructive sleep apnea (OSA). Conventional maxillary expander treatment has been used in children with OSA to expand constricted maxilla to increase nasal flow and to allow the tongue to protrude forward and upward. With the in...
Article
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Background The study aimed to evaluate the anatomical differences between positional and non-positional OSA, and to identify the potential predictors for distinguishing between these two types of OSA. Methods A cross-sectional study of 230 consecutive patients with OSA undergoing DISE (Drug-induced Sleep Endoscopy) was carried out at a tertiary ac...
Article
Purpose The apnea-hypopnea index (AHI) is the parameter on which the severity of obstructive sleep apnea (OSA) is based and is also the determinant for both clinicians and third-party payers for surgical procedures. The purpose of this retrospective cross-sectional chart review is to examine differences in symptoms and AHI between men and women wit...
Article
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With the advent of precision surgery, there have been attempts to integrate imaging with robotic systems to guide sound oncologic surgical resections while preserving critical structures. In the confined space of transoral robotic surgery (TORS), this offers great potential given the proximity of structures. In this cadaveric experiment, we describ...
Article
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There are many ways to categorize surgery for obstructive sleep apnea (OSA), one of which is to distinguish between intrapharyngeal and extrapharyngeal procedures. While the general otolaryngologist treating OSA is familiar with intrapharyngeal procedures, such as uvulopalatopharyngoplasty and tongue base reduction, extrapharyngeal sleep operations...
Article
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Sleep surgery is part of a continuum of care for OSA that involves medical, pharmacologic, and behavioral therapy. Upper airway surgery for OSA can significantly improve stability by way of modulating the critical negative closing pressure. This is the same mechanism of action as PAP or oral appliance therapy (OAT). The updated surgical algorithm i...
Article
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Background: This study was conducted to evaluate the relationship between nasal resistance in different posture and optimal positive airway pressure (PAP) level. Other potential factors were also assessed for possible influence on PAP pressure. Methods: Forty- three patients diagnosed with obstructive sleep apnea (OSA) were prospectively recruit...
Article
OBJECTIVE Inferior turbinates are the main structure related to impaired nasal breathing. When medical treatment fails, surgery is the next step, according to clinical guidelines. However, despite the widespread acceptance of this procedure, there is some controversy about performing it in children. DATA SOURCES Pubmed (Medline), the Cochrane Libr...
Article
OBJECTIVE A reduced transversal dimension of the maxilla leads to narrower nasal cavities, which may reduce airflow to the lungs. Maxillary expansion widens nasal floor. However, there is huge controversy regarding whether this increase does actually lead to increased airflow. In this systematic review and meta-analysis we aim to resolve this quest...
Article
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Objectives Maxillomandibular advancement (MMA) confers consistent and high rates of surgical success for obstructive sleep apnea (OSA). In the era of value-based medicine, identifying factors that affect the stability of rigid fixation and allow rapid return to function are important targets for improvement. The aim of this study was to identify pa...
Article
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Objective Distraction osteogenesis maxillary expansion (DOME) is a reliable method to expand the nasal floor and hard palatal vault in adults with obstructive sleep apnea (OSA). DOME results in a reduction in the apnea-hypopnea index (AHI) and subjective report of improved nasal breathing. Using rhinomanometry augmented computational fluid dynamic...
Article
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Background: To systematically review the literature for methods to localize the genial tubercle as a means for performing an advancement of the genioglossus muscle. Methods: PubMed, Google Scholar, CRISP, EMBASE, CINAHL, and Scopus were searched from inception through June 16, 2015. Results: One hundred fifty-two articles were screened, and th...
Article
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Obstructive sleep apnoea (OSA) is characterized by repeated upper airway collapse leading to oxygen desaturation resulting in cardiovascular and neurocognitive sequelae. Upper airway surgeries such as palatopharyngoplasty, tongue base surgery, and maxillomandibular advancement can improve patient tolerance of continuous positive airway pressure, qu...
Article
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Background: Ankyloglossia is a condition of altered tongue mobility due to the presence of restrictive tissue between the undersurface of the tongue and the floor of mouth. Potential implications of restricted tongue mobility (such as mouth breathing, snoring, dental clenching, and myofascial tension) remain underappreciated due to limited peer-re...
Article
Introduction While studies have demonstrated hypoglossal nerve stimulation (HNS) to be a safe and overall effective treatment for certain patients with obstructive sleep apnea (OSA), not all who meet current selection criteria respond to therapy. In an effort to elucidate better criteria for patient selection, this study aimed to look at the effect...
Article
Introduction The current protocol for patients after undergoing upper airway surgery (UAS) for obstructive sleep apnea (OSA) involves activation in clinic 1 month after the procedure, and titration in the sleep lab 2 months after the procedure. Some patients are intolerant of settings obtained from the titration study for optimal reduction of the a...
Article
Introduction Upper airway stimulation (UAS) is increasingly recognized as a reliable and safe treatment modality for well-selected patients with moderate-to-severe obstructive sleep apnea (OSA) and continuous positive airway pressure (CPAP) failure. This study characterizes patient demographics and their clinical path taken towards UAS in an academ...
Article
Introduction Obstructive sleep apnea syndrome (OSAS) may be related to tinnitus and hearing loss. However, there are no prospective cohort studies to discuss the relationship between sensorineural hearing loss (SNHL) and continuous positive airway pressure (CPAP) treatment in OSAS patients. Our study is to analyze the correlation between these. Me...
Article
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Objective: to assess the effect of Distraction Osteogenesis Maxillary Expansion (DOME) on objective parameters of the internal nasal valve and correlate findings with subjective outcomes. Study Design: Retrospective cohort study Setting: Tertiary referral center Subjects and Methods: After IRB approval, subjects with OSA undergoing DOME from Septe...
Article
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Objective: To determine the contribution of the nasal floor and hard palate morphology to nasal obstruction for nonresponders to prior intranasal surgery. Study design: Retrospective case-control study. Setting: Tertiary academic center. Methods: Institutional review board-approved, retrospective institutional database analysis was obtained...
Article
Whereas the original Stanford protocol relied on a tiered approach to care to avoid unnecessary surgery, it did not address the issue of surgical relapse, a common concern among sleep medicine specialists. With 3 decades of experience since the original 2-tiered Powell-Riley protocol was introduced and the role of evolving skeletal techniques and u...
Article
Maxillomandibular advancement (MMA) for the treatment of obstructive sleep apnea (OSA) has remained a reliable and highly effective surgical intervention since its introduction in 1989. Modifications have been made to maximize skeletal movement and upper airway stability without compromising facial balance. Contemporary indications of recommending...
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Article
Background: Nasal obstruction is associated with snoring, sleep disordered breathing, and OSA. Abnormal nasal physiology is an important aspect of OSA etiology. Aims/objectives: To perform a systematic review and meta-analysis to determine if isolated nasal surgery in patients with and without OSA could improve sleep quality after surgery. Material...
Article
Purpose: Persons with obstructive sleep apnea (OSA) are at heightened risk of myocardial infarction (MI) and stroke caused by adiposity and intermittent hypoxia, which provoke proinflammatory cytokines to induce systemic and vascular inflammation, resulting in endothelial dysfunction and development of atherosclerotic plaque. This study compared l...
Article
Objective To evaluate the association between findings of blinded reviews of preoperative drug‐induced sleep endoscopy (DISE) examinations using the VOTE Classification and obstructive sleep apnea (OSA) surgical outcomes in a large multicenter, international cohort. Methods Retrospective, multi‐center cohort study of adults without tonsillar hyper...
Article
Objectives/hypothesis: The objective of this study was to systematically review the English literature for articles that have described skeletal surgeries in the treatment of obstructive sleep apnea in both adults and children. From these articles trends and patterns in the treatment of OSA with skeletal procedures are described. Study design: T...
Poster
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Complete concentric collapse (CCC) of the velum from drug-induced sleep endoscopy (DISE) is a key finding in surgical selection, particularly for upper airway stimulation. We aim to correlate facial CT morphometric measurements with CCC of the velum. We hypothesize that maxillary transverse hypoplasia is correlated with CCC of the velum.
Article
Objectives/hypothesis: Examine US and international clinical trials in obstructive sleep apnea (OSA) to characterize researchers involved, interventions being studied, and opportunities for future investigation. Study design: Retrospective database review. Methods: The information from ClinicalTrials.gov was used to assess OSA clinical trials...
Article
Purpose: Hypoxemia and hypertension caused by obstructive sleep apnea (OSA) often result in atherosclerosis of the carotid and coronary vessels and heightened risk of stroke and myocardial infarction (MI). Therefore, this study investigated whether severity of OSA, based on the apnea-hypopnea index (AHI), is associated with the presence of calcifi...
Article
Study objectives: Patients suspected to have sleep-disordered breathing underwent an overnight polysomnography using a divided nasal cannula to gain additional information about the nasal cycle during sleep. Methods: This was a prospective, observational cohort study replacing the undivided nasal cannula with a divided nasal cannula during routi...
Article
Purpose Assess the quality of information on obstructive sleep apnea (OSA) presented on YouTube for patients. Materials and methods “Obstructive sleep apnea” was entered into the YouTube search. Two independent reviewers categorized and analyzed videos utilizing a customized scoring-system along with search position, likes, and views. Results For...
Article
Large, benign intramandibular lesions are frequently removed by resection followed by extensive free tissue transfer or delayed bone grafting. We outline a protocol to remove benign mandibular lesions using sagittal split osteotomy (SSO) with virtual surgical planning (VSP) to mitigate risks involved with this effective, tissue-saving approach. Pat...
Article
Objectives/Hypothesis Examine trends in clinical research and levels of evidence related to obstructive sleep apnea (OSA) in the medical literature. Describe the features and trends of OSA research within otolaryngology journals. Study Design Retrospective analysis. Methods Review of OSA research articles from 2006, 2011, and 2016 in four lead...
Article
Objective: To validate the use of Cormack-Lehane and Modified Cormack-Lehane scoring systems to classify patterns of hypopharyngeal airway visualization seen during awake flexible laryngoscopy among patients with obstructive sleep apnea. Study design: Validation study using samples collected from a prospective database. Setting: University Med...
Article
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The prevalence of obstructive sleep apnea (OSA) is estimated to be 1–5% of the adult population world-wide, and in Korea, it is reported at 4.5% of men and 3.2% of women (Age 40 to 69 years old). Active treatment of OSA is associated with decrease in insulin resistance, cardiovascular disease, psychosocial problems, and mortality. Surgical treatmen...
Article
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Objectives: To characterize associations between restricted tongue mobility and maxillofacial development. Setting and sample population: Cross-sectional cohort study of 302 consecutive subjects from an orthodontic practice. Material and methods: Tongue mobility (measured with tongue range of motion ratio [TRMR] and Kotlow free tongue measurem...
Article
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Objectives: Patients with mandibular insufficiency can be predisposed to obstructive sleep apnea (OSA). The objective of this study was to systematically review the international literature for mandibular advancement surgeries (MAS) as treatment for adult OSA, and then to perform a meta-analysis. Methods: Four authors searched five databases fro...