About

Dr. Marshall E. Smith is a professor of Otolaryngology-Head and Neck Surgery at the University of Utah and Primary Children’s Hospital. He is a board-certified otolaryngologist and the medical director of the Voice Disorders Center. He completed his residency in Otolaryngology at UCLA and a fellowship in Pediatric Otolaryngology in Cincinnati. He is an NIH-funded investigator and participates in research on various voice disorders. Dr. Smith provides evaluation, medical, and surgical care of the voice and is the medical director of a multidisciplinary team dedicated to comprehensive care of the larynx.

Research topics

• Medicine
• Surgery
• Internal medicine
• Pediatrics
• Physical therapy
• Anesthesia
• Demography
• Audiology
• Intensive care medicine
• Medical physics

Selected publications

• Amniotic Fluid as a Potential Treatment for Vocal Fold Scar in a Rabbit Model

  Journal of Voice · 2025-01-01 · 2 citations

  article
  PublisherDOI

• Update of Long‐Term Outcomes After Cricotracheal Resection for Idiopathic Subglottic Stenosis

  The Laryngoscope · 2025-06-19

  articleOpen accessSenior author

  OBJECTIVES: Idiopathic subglottic stenosis (iSGS) is a rare disease in which patients develop dyspnea from recurrent tracheal granulation scar. We present our long-term outcomes after crico-tracheal resection (CTR) for iSGS at a high-volume tertiary care center. We update our previous report in 2018 with seven additional years of follow-up. METHODS: A review was conducted with iSGS patients who underwent CTR between 1999 and 2017. Diagnosis of iSGS was based on history and bronchoscopy exam. Recurrence of iSGS was evaluated using survivability and the Kaplan-Meier curve. Management of recurrence post-CTR was investigated with Pearson correlation analysis. RESULTS: Sixty-one patients with iSGS underwent CTR. Our population was 98% female. Twenty (33%) patients developed recurrence after CTR. The mean time to recurrence was 13.8 years (range = 0.8-16.3). Seven (11%) patients had not recurred up to 21.9 years post-CTR. There was a negative correlation (-0.45, p = 0.046) between age at recurrence and number of procedures per year to treat recurrent stenosis. Six (10%) patients were deceased from unrelated causes at follow-up and on average 6 years post-CTR (range = 0.8-15.8). One patient recurred prior to her death. CONCLUSION: Our 2018 report included a mean recurrence time of 12.5 years (range = 0.8-14.3). This follow-up showed an even longer time to recurrence (average = 13.8 years). CTR is associated with a low recurrence rate of stenosis. Older patients may be better candidates for CTR than younger patients. Further research should investigate risk factors that predispose patients to recurrence after CTR.

  PublisherOA PDFDOI

• Comparing the Effects of Sensory Tricks on Voice Symptoms in Patients With Laryngeal Dystonia and Essential Vocal Tremor

  Journal of Speech Language and Hearing Research · 2025-02-27 · 7 citations

  articleOpen access

  PURPOSE: This pilot study systematically compared voice symptomatology across varied sensory trick conditions in those with laryngeal dystonia (LD), those with essential vocal tremor (EVT), and vocally normal controls (NCs). Sensory tricks are considered signature characteristics of dystonia and were hypothesized to reduce voice symptoms in those with LD compared to EVT and NC groups. METHOD: Five participants from each group (LD, EVT, and NC) completed speech recordings under control and sensory trick conditions (delayed auditory feedback [DAF], vibrotactile stimulation [VTS], and nasoendoscopic recordings with and without topical anesthesia). Comparisons between groups and conditions were made using (a) a paired-comparison paradigm (control vs. sensory condition) listener ratings of voice quality, (b) participant-perceived vocal effort ratings, and (c) average smoothed cepstral peak prominence (CPPS). RESULTS: Participants with EVT displayed significantly worse listener ratings under most sensory trick conditions, whereas participants with LD were rated significantly worse for DAF and VTS conditions only. However, participant vocal effort ratings were similar across all sensory trick conditions. Average CPPS values generally supported listener ratings across conditions and speakers except during DAF, wherein CPPS values increased (i.e., measurably improved voice quality), whereas listener ratings indicated worsened voice quality for both voice disorder groups. CONCLUSIONS: Outcomes of this study did not support the hypothesized influences of sensory trick conditions on LD voice symptoms, with both LD and EVT groups experiencing worsened symptoms under VTS and DAF conditions. These adverse effects on voice symptoms warrant further research to further evaluate neural pathways and associated sensorimotor response patterns that distinguish individuals with LD and EVT. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.28462292.

  PublisherOA PDFDOI

• Comparative Study of Two Semi-Occluded Vocal Tract Protocols: A Randomized Clinical Trial

  Journal of Speech Language and Hearing Research · 2024-10-22 · 9 citations

  articleOpen access

  Introduction: Semi-occluded vocal tract exercises (SOVTEs) are widely used as a therapeutic tool to create flow resistance in the upper airway. The current study was a randomized controlled clinical trial to establish the efficacy of two SOVTE protocols, flow-resistant tube (FRT) and Lessac-Madsen Resonant Voice Therapy (LMRVT). Exploratory investigations included a noninferiority analysis of FRT to the widely adopted therapy protocol (LMRVT), as well as examining the dosing required to improve acoustic measures and subjective ratings. Method: Sixty-seven participants with voice disorder were randomized into one of five groups: 4-week FRT ( n = 14), 8-week FRT ( n = 19), 4-week LMRVT ( n = 15), 8-week LMRVT ( n = 5), and control ( n = 14). Voice Handicap Index (VHI) and Vocal Fatigue Index scores were collected pre- and posttreatment. Acoustic analysis using the Acoustic Voice Quality Index was completed. We compared VHI between controls and 8-week FRT and LMRVT, adjusting for pre-VHI using linear regression. We examined the efficacy of 4-week protocols relative to controls and conducted a noninferiority comparison of FRT (4 and 8 weeks) to LMRVT (4 and 8 weeks) using 5- and 10-point margins. Finally, we compared the 4- versus 8-week sessions for both therapies. Results: A statistically significant reduction of VHI in both 8-week FRT relative to controls (−10.60, 95% CI [−19.80, −1.40], p = .025) and 8-week LMRVT (−15.74, 95% CI [−29.40, −2.08], p = .025) was found. We also found an improvement in 4-week FRT relative to controls (−10.11, 95% CI [−20.03, −0.20], p = .046), but the 4-week LMRVT result was not statistically significant ( p = .057). FRT was found to be noninferior to LMRVT in terms of VHI using a 10-point margin (FRT − LMRVT: 0.69, 95% CI [−5.76, 7.15], p = .01), but not using a 5-point margin ( p = .054). There were no statistically significant differences in VHI scores between 4- and 8-week sessions for either therapy. Conclusions: Both FRT and LMRVT improved VHI scores relative to controls. FRT was noninferior to LMRVT in terms of VHI scores. There were no statistically significant differences in VHI scores between 4- and 8-week therapy sessions.

  PublisherOA PDFDOI

• <scp>Long‐Term</scp> Outcomes and Revision Rates in Laryngeal Reinnervation

  The Laryngoscope · 2024 · 7 citations

  Senior authorCorresponding
  • Medicine
  • Surgery
  • Anesthesia

  OBJECTIVES: Nonselective laryngeal reinnervation is an effective procedure to improve voice quality after unilateral vocal fold paralysis. Few studies have captured long-term outcome data, and the revision rate for this operation is currently unknown. The objective of this study is to describe the long-term outcomes and revision rates of unilateral, nonselective reinnervation in pediatric and adult patients. METHODS: Patients who underwent laryngeal reinnervation from 2000 to 2022 with a single surgeon were identified for inclusion. Patients who underwent bilateral, super selective, deinnervation and reinnervation, and/or concurrent arytenoid adduction procedures were excluded. Outcome measures included maximum phonation time [MPT], voice handicap index score [VHI], patient-reported percent normal voice, revision procedures, and complications. Data were compiled and analyzed using paired t-tests, repeated measures analysis of covariance, and binary logistic regression analysis. RESULTS: One hundred thirty-two patients underwent unilateral, nonselective ansa-recurrent laryngeal nerve [RLN] laryngeal reinnervation. Reinnervation significantly improved MPT and patient-reported percentage of normal voice and significantly decreased VHI. Eleven patients underwent revision procedures, corresponding to a revision rate of 8.3%. Additional procedures included medialization laryngoplasty [n = 3], medialization laryngoplasty with arytenoid adduction [n = 3] and injection augmentation greater than 1 year after reinnervation [n = 5]. The only factor associated with the need for additional surgery was time lapse from nerve injury to reinnervation. The overall complication rate was 6.8%; no patient required reintubation or tracheostomy. CONCLUSION: Unilateral, nonselective laryngeal reinnervation can provide reliable improvement in vocal symptoms after recurrent laryngeal nerve injury. The revision rate after laryngeal reinnervation is favorable and comparable to framework surgery. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:3187-3192, 2024.

  PublisherOA PDFDOI

• Type II Thyroplasty with Bilateral Partial Cricothyroid Myectomy for Vocal Tic in Child with Cerebral Dysgenesis

  Journal of Voice · 2024-03-01

  articleSenior authorCorresponding
  PublisherDOI

• Predominantly unilateral laryngomalacia in infants with unilateral vocal fold paralysis

  International Journal of Pediatric Otorhinolaryngology · 2024-03-21 · 2 citations

  article
  PublisherDOI

• The Diagnosis of Granulomatosis With Polyangiitis When Serology and Biopsies are Negative

  OTO Open · 2024-04-01 · 7 citations

  articleOpen accessSenior author

  Abstract Objective Granulomatosis with polyangiitis (GPA) is a potentially fatal condition which often manifests in the head and neck. Currently, diagnosis relies on antineutrophil cytoplasmic autoantibody (c‐ANCA) serology and mucosal or renal biopsy. However, a significant proportion of patients with GPA limited to the head and neck are seronegative and biopsy negative. This study evaluates the role of clinical diagnosis of GPA in the absence of positive laboratory findings. Study Design Case series with chart review. Setting Academic Tertiary Medical Center. Methods This was a retrospective review of 143 patients treated in an outpatient otolaryngology clinic at a tertiary care hospital for known or suspected GPA from 1998 to 2021. Presenting symptoms, C‐ANCA status at initial presentation, biopsy results, long‐term serology results, and time to initiation of treatment were analyzed. Results Twenty‐six of 143 (18.2%) patients were seronegative; only 3 of these patients (12%) had positive biopsies. Seventeen (73.9%) of these patients presented with nasal and sinus disease and 12 (52.2%) presented with airway involvement. Only 4 (17.4%) patients had renal involvement. Delay in treatment of patients with negative laboratory workup ranged from 0 months to 11 years. All patients who were seronegative and/or biopsy negative at presentation responded clinically to immunosuppressive therapy. Conclusion GPA cases are often limited to the upper respiratory tract, making diagnosis difficult, particularly in seronegative patients. These results suggest that, when GPA is suspected, despite negative serology, the diagnosis of GPA should be made on clinical grounds, and empiric therapy encouraged to prevent delay in treatment.

  PublisherOA PDFDOI

• Optimization of Subglottic View During Flexible Laryngoscopy With Patient Positioning

  Otolaryngology · 2023-07-31 · 2 citations

  articleOpen accessSenior author

  OBJECTIVE: Determine the ideal head position to optimize visualization of the subglottis using flexible laryngoscopy. STUDY DESIGN: Prospective cohort study. SETTING: Outpatient multidisciplinary airway clinic at a tertiary care center. METHODS: Patients presenting to a multidisciplinary airway clinic undergoing nasoendoscopic airway examination were enrolled. Three head positions were utilized to examine the subglottis during laryngoscopy: "sniffing," chin tuck, and stooping positions. In-office reviewers and blinded clinician participants evaluated views of the airway based on Cormack-Lehane (CL) scale, airway grade (AG), and visual analog scale (VAS). Demographic data were obtained. Statistical analysis compared head positions and demographic data using Student's t test, analysis of variance, and Tukey's post hoc analysis. RESULTS: One hundred patients participated. No statistical differences existed among in-clinic or blinded reviewers for the CL score in any head position (p = .35, .5, respectively). For both AG and VAS, flexed and stooping positions were rated higher than the sniffing positions by both in-clinic and blinded reviewers (p < .01 for all analyses), but there was no statistical difference between these two positions (p = .28, .18, respectively). There was an inverse correlation between age and scores for AG and VAS in the flexed position for both sets of reviewers (p = .02, <.01 respectively), and a higher body mass index was significantly associated with the need to perform tracheoscopy for full airway evaluation (p < .01). CONCLUSION: Both flexion and stoop postures can be implemented by an experienced endoscopist in awake, transnasal flexible laryngoscopy to enhance visualization of the subglottic airway.

  PublisherOA PDFDOI

• Comparative Treatment Outcomes for Idiopathic Subglottic Stenosis: 5‐Year Update

  Otolaryngology · 2023 · 30 citations

  • Medicine
  • Surgery
  • Physical therapy

  The North American Airway Collaborative (NoAAC) previously published a 3-year multi-institutional prospective cohort study showing variation in treatment effectiveness between 3 primary surgical techniques for idiopathic subglottic stenosis (iSGS). In this report, we update these findings to include 5 years of data evaluating treatment effectiveness. Patients in the NoAAC cohort were re-enrolled for 2 additional years and followed using the prespecified published protocol. Consistent with prior data, prospective observation of 487 iSGS patients for 5 years showed treatment effectiveness differed by modality. Cricotracheal resection maintained the lowest rate of recurrent operation (5%), followed by endoscopic resection with adjuvant medical therapy (30%) and endoscopic dilation (50%). These data support the initial observations and continue to provide value to providers and patients navigating longitudinal decision-making. Level of evidence: 2-prospective cohort study.

  PublisherDOI

Recent grants

• NIH Grant R21DC007166

  NIH · $407k · 2009

• NIH Grant K08DC000132

  NIH · $113k · 2003

Frequent coauthors

• Lorraine O. Ramig

  LSVT Global (United States)

  52 shared

• Erich S. Luschei

  University of Iowa

  32 shared

• Kristin Baker

  Howard Brown Health Center

  30 shared

• Nelson Roy

  Google (United States)

  28 shared

• Harlan Muntz

  UC Davis Children's Hospital

  24 shared

• Gerald S. Berke

  University of California, Los Angeles

  23 shared

• Harlan R. Muntz

  22 shared

• Charles M. Myer

  University of Cincinnati Medical Center

  21 shared

Education

• M.D., Otolaryngology

  UCLA

• Other, Pediatric Otolaryngology

  Cincinnati