Clinical Focus

  • Otolaryngology - Head & Neck Surgery (Ear, Nose and Throat)
  • Otolaryngology
  • Pediatric Otolaryngology
  • Sleep Apnea, Obstructive
  • Microtia
  • Vascular Malformations

Academic Appointments

  • Clinical Associate Professor, Otolaryngology - Head & Neck Surgery Divisions

Professional Education

  • Board Certification: Otolaryngology, American Board of Otolaryngology (2009)
  • Fellowship:Stanford University School of Medicine (2009) CA
  • Medical Education:University of California Irvine (2003) CA
  • Residency:Stanford University School of MedicineCA
  • Internship:Stanford University School of MedicineCA


All Publications

  • Renal ultrasound abnormalities in children with syndromic and non-syndromic microtia. International journal of pediatric otorhinolaryngology Koenig, J. L., Amoils, M., Grade, M. M., Chang, K. W., Truong, M. T. 2018; 113: 173–76


    OBJECTIVE: Renal abnormalities are commonly considered in the work up of pediatric patients with external ear malformations. However, there is little consensus regarding an appropriate renal screening protocol for patients with microtia. We sought to characterize renal abnormalities detected on ultrasonography in pediatric patients with microtia.METHODS: We conducted a retrospective cohort study of pediatric patients diagnosed with microtia who underwent renal ultrasound from 1991 to 2014 at a single tertiary academic institution. Renal ultrasound reports and medical records were reviewed to assess for renal abnormalities and to determine whether patients required specialist follow-up or interventions. Audiograms and otolaryngology notes were used to determine patterns of hearing loss. The following additional information was recorded from the electronic medical records: patient sex, microtia grade (I-IV), microtia laterality, and known associated syndromes. Characteristics were compared between those who did and did not have renal ultrasound findings using Fisher's exact test. Univariate logistic regression analysis was performed to determine factors associated with renal ultrasound findings.RESULTS: The majority of patients in this cohort were syndromic (n = 51, 64%) with grade III microtia (n = 46, 58%) and conductive hearing loss (n = 58, 72%). Syndromic children with microtia demonstrated a higher crude rate of renal ultrasound abnormalities (22%) than children with isolated microtia (7%). Of these patients, 69% required specialist follow-up. Univariate logistic regression analysis did not identify predictors that were significantly associated with renal ultrasound findings.CONCLUSION: Fairly high rates of abnormalities in syndromic and non-syndromic patients may warrant screening renal ultrasound in all patients with microtia, especially given the high percentage of findings requiring renal follow-up. A prospective study to formally evaluate screening efficacy is needed.

    View details for DOI 10.1016/j.ijporl.2018.07.026

    View details for PubMedID 30173979

  • A child with silent sinus syndrome and spontaneous improvement after sinus surgery. International journal of pediatric otorhinolaryngology Chang, D. T., Truong, M. T. 2014; 78 (11): 1993-1995


    Silent sinus syndrome is characterized by an asymptomatic hypoplastic maxillary sinus with progressive enophthalmos and hypoglobus. This is a disease rarely affecting children with the majority of reported cases involving adult patients. Treatment is primarily surgical with endoscopic sinus surgery to restore aeration of the sinus along with orbital reconstruction to restore facial symmetry. In this report, we describe a 7 year old child with facial asymmetry and no sinonasal symptoms. CT showed an opacified hypoplastic right maxillary sinus. One year after endoscopic sinus surgery, there was spontaneous improvement of facial asymmetry and relative maxillary sinus size.

    View details for DOI 10.1016/j.ijporl.2014.08.002

    View details for PubMedID 25218341

  • A child with silent sinus syndrome and spontaneous improvement after sinus surgery INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Chang, D. T., Mai Thy Truong, M. T. 2014; 78 (11): 1993-1995
  • beta-Adrenergic receptor expression in vascular tumors MODERN PATHOLOGY Chisholm, K. M., Chang, K. W., Truong, M. T., Kwok, S., West, R. B., Heerema-McKenney, A. E. 2012; 25 (11): 1446-1451


    Propranolol has recently emerged as an effective therapy for infantile hemangiomas causing regression. The β-adrenergic receptor (AR) antagonist is thought to cause vasoconstriction by its effect on nitric oxide, block angiogenesis by its effect on vascular endothelial growth factor (VEGF), and induce apoptosis. In a prior report, we identified expression of β2-AR (B2-AR) and its phosphorylated form (B2-ARP) in a case of infantile hemangioma that responded to propranolol treatment. We now explore the expression of βARs on a variety of vascular lesions utilizing a tissue microarray containing 141 lesions, including infantile hemangiomas, angiosarcomas, hemangiomas, hemangioendotheliomas, and various vascular malformations. The array was immunostained for B2-AR, B2-ARP, and β3-AR (B3-AR), and the results scored for the intensity of endothelial cell expression as negative, weak positive, or strong positive. All phases of infantile hemangiomas had strong expression of all three receptors, with the exception of only weak expression of B2-ARP in the proliferative phase infantile hemangioma. Strong expression of all three receptors was present in many hemangiomas, hemangioendotheliomas, and vascular malformations. Absent to weak expression of all three receptors was seen in glomus tumor, hobnail hemangioendothelioma, pyogenic granuloma, and reactive vascular proliferations. This is the first study to report β-AR expression in a variety of vascular lesions. Although immunohistochemical expression of the receptors does not necessarily indicate that similar pathways of responsiveness to β-blockade are present, it does raises the possibility that β-blockade could potentially affect apoptosis and decrease responsiveness to VEGF. Additional study is warranted, as therapeutic options are limited for some patients with these lesions.

    View details for DOI 10.1038/modpathol.2012.108

    View details for Web of Science ID 000310795400002

    View details for PubMedID 22743651

  • Sleep endoscopy as a diagnostic tool in pediatric obstructive sleep apnea INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Truong, M. T., Woo, V. G., Koltai, P. J. 2012; 76 (5): 722-727


    Ten to twenty percent of children have persistent obstructive sleep apnea (OSA) after adenotonsillectomy (T&A). We hypothesize that sleep endoscopy, a flexible fiberoptic examination of the pharynx under anesthesia, is an effective tool for identifying sites of persistent obstruction.In this retrospective cohort study, we reviewed records of children who had symptoms consistent with OSA and a positive polysomnogram (PSG) who underwent sleep endoscopy followed by sleep endoscopy directed surgery. Data collection included age, BMI and co-morbidities. Apnea-hypopnea index (AHI) was compared to pre and post surgery for each child using a paired t-test.Of the 80 children who underwent sleep endoscopy followed by directed surgery, 65% were male, mean age was 6 years (SD 3.75 years), average BMI was 19 (SD 0.43 years) and 28% had co-morbidities. For the 51% of patients who had persistent OSA after T&A, the mean AHI after sleep endoscopy directed surgery was significantly lower then before surgery (7.9 vs. 15.7, p<.01). For the 49% of patients who had never undergone surgery for OSA, or who were surgically naïve, and underwent sleep endoscopy directed surgery, the mean AHI was significantly lower then before surgery (8.0 vs. 13.8, p<.01).Sleep endoscopy is a consistently reliable tool for identifying the sites of obstruction in both surgically naive children and those with persistent OSA after T&A.

    View details for DOI 10.1016/j.ijporl.2012.02.028

    View details for Web of Science ID 000303901400021

    View details for PubMedID 22421163

  • Supraglottoplasty for Occult Laryngomalacia to Improve Obstructive Sleep Apnea Syndrome ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY Chan, D. K., Mai Thy Truong, M. T., Koltai, P. J. 2012; 138 (1): 50-54


    To evaluate the polysomnographic outcomes after supraglottoplasty (SGP) performed for obstructive sleep apnea syndrome (OSAS) associated with occult laryngomalacia.Retrospective case series with medical chart review.Tertiary pediatric medical center.Twenty-two patients aged 2 to 17 years met the inclusion criteria of polysomnography-proven OSAS and occult laryngomalacia seen on flexible fiber-optic sleep endoscopy. Infants with congenital laryngomalacia were excluded.Carbon dioxide laser SGP was performed either alone or in conjunction with other operations for OSAS.Preoperative and postoperative nocturnal polysomnographic data were paired and analyzed statistically.Supraglottoplasty for occult laryngomalacia resulted in statistically significant reduction in the apnea-hypopnea index (AHI) (from 15.4 to 5.4) (P <.001). Subgroup analysis of children who underwent either SGP alone or in combination with other interventions showed comparable reductions in AHI. Medical comorbidities were associated with worsened postoperative outcomes, although still significantly improved compared with baseline. Overall, 91% of children had an improvement in AHI, and 64% had only mild or no residual OSAS after SGP.Supraglottoplasty is an effective technique for the treatment of OSAS associated with occult laryngomalacia.

    View details for Web of Science ID 000299131300009

    View details for PubMedID 22249629

  • Propranolol for the treatment of airway hemangiomas: A case series and treatment algorithm INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Truong, M. T., Perkins, J. A., Messner, A. H., Chang, K. W. 2010; 74 (9): 1043-1048


    (1) To present six patients with symptomatic airway hemangiomas treated with oral propranolol. (2) To review the diagnostic and treatment options for airway hemangiomas and propose a new management protocol.Retrospective review.Tertiary care children's hospital.Pediatric patients diagnosed with obstructive airway hemangiomas treated with oral propranolol. Patients were followed for symptomatic improvement and relief of airway obstruction on imaging or laryngoscopy.Seven patients presenting with airway obstruction were treated with propranolol. One patient had a focal hemangioma confined to the subglottis. Four patients had airway hemangiomas that extended beyond the confines of the larynx and trachea. A sixth patient had a bulky supraglottic hemangioma. A seventh patient with an extensive maxillofacial lesion failed propranolol therapy and was found to have a pyogenic granuloma on final pathology after excision. Six patients had failed standard medical therapy and/or surgical interventions and were treated successfully with oral propranolol with improvements in airway symptoms and oral intake, requiring no further surgical intervention. Treatment was initiated as early as 1.5 months of age, and as late as 22 months. No adverse side effects of propranolol were noted.Oral propranolol was successfully used to treat airway hemangiomas, resulting in rapid airway stabilization, obviating the need for operative intervention, and reducing the duration of systemic corticosteroid therapy while causing no obvious adverse effects. These outstanding results enable the possibility of use of a standardized diagnostic and treatment algorithm for airway hemangiomas that incorporates systemic propranolol.

    View details for DOI 10.1016/j.ijporl.2010.06.001

    View details for Web of Science ID 000281615300015

    View details for PubMedID 20674045

  • Propranolol for the Treatment of a Life-Threatening Subglottic and Mediastinal Infantile Hemangioma JOURNAL OF PEDIATRICS Truong, M. T., Chang, K. W., Berk, D. R., Heerema-McKenney, A., Bruckner, A. L. 2010; 156 (2): 335-338


    An infant with a subglottic hemangioma remained in respiratory distress after multiple treatments failed and was found to have an enlarging mediastinal infantile hemangioma compressing the trachea. Treatment with oral propranolol resulted in resolution of symptoms within 2 days and a 50% reduction in lesion size within 1 week.

    View details for DOI 10.1016/j.jpeds.2009.10.010

    View details for Web of Science ID 000274051500038

    View details for PubMedID 20105647

  • Primary Hyperparathyroidism in Pregnancy: A Case Series and Review Annual Meeting of the Western Section of the Triological-Society Truong, M. T., Lalakea, M. L., Robbins, P., Friduss, M. WILEY-BLACKWELL. 2008: 1966–69


    To review the clinical significance of primary hyperparathyroidism during pregnancy including the maternal, fetal, and neonatal sequelae. Additionally, to discuss treatment options and describe three cases where surgical parathyroidectomy was successful for treatment of hyperparathyroidism refractory to medical management during pregnancy.Retrospective.We reviewed three cases of hyperparathyroidism during pregnancy and reviewed the literature.Three women underwent surgical parathyroidectomy during their second and third trimester of pregnancy without any maternal, fetal, or neonatal complications.Hyperparathyroidism during pregnancy may be safely treated with surgical parathyroidectomy if refractory to medical management with low operative risk when performed during the second trimester. This surgical option should be considered in light of the known maternal, fetal, and neonatal risks because of the hypercalcemic state in pregnancy.

    View details for DOI 10.1097/MLG.0b013e318180276f

    View details for Web of Science ID 000260874700011

    View details for PubMedID 18758377

  • Pediatric vocal fold paralysis after cardiac surgery: Rate of recovery and sequelae OTOLARYNGOLOGY-HEAD AND NECK SURGERY Truong, M. T., Messner, A. H., Kerschner, J. E., Scholes, M., Wong-Dominguez, J., Milczuk, H. A., Yoon, P. J. 2007; 137 (5): 780-784


    To determine the rate of recovery of pediatric vocal fold paralysis (VFP) after cardiac surgery.Retrospective case series from January 2000 to 2005 at 4 tertiary care pediatric hospitals.A total of 109 children with VFP were identified. Of 80 patients with follow-up >3 months, 28 (35%) recovered vocal fold function with a median time to diagnosis of recovery of 6.6 months. Fifty-two (65%) patients had persistent vocal fold paralysis with a median follow-up time of 16.4 months. Twenty-five (45%) of 55 patients demonstrated aspiration or laryngeal penetration with modified barium swallow. Twenty-nine (27%) of the 109 patients underwent surgical intervention for their airway, feeding, or voice.Pediatric VFP is not an uncommon complication after cardiac surgery and can result in serious sequelae. This study demonstrates a 35% rate of recovery, 45% rate of aspiration, and 27% rate of complications that require surgical intervention.

    View details for DOI 10.1016/j.otohns.2007.07.028

    View details for Web of Science ID 000250821700017

    View details for PubMedID 17967646

  • Recovery from cisplatin-induced ototoxicity: A case report and review INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Truong, M. T., Winzelberg, J., Chang, K. W. 2007; 71 (10): 1631-1638


    We present a pediatric case report of cisplatin-induced ototoxicity with subsequent recovery. The patient experienced tinnitus and fluctuating mild high-frequency sensorineural hearing loss (SNHL) with a concomitant decrease in distortion product otoacoustic emissions (DPOAE). There was recovery of hearing loss and return of DPOAE at 1 year after completion of cisplatin therapy. Reports of recovery from cisplatin-induced ototoxicity in humans are limited in the literature, especially in the pediatric population. A review of cisplatin ototoxicity and mechanisms of recovery are discussed, with an emphasis on the particular chemotherapy regimen and dosing schedule in this case, given at 4-11 week intervals.

    View details for DOI 10.1016/j.ijporl.2007.06.021

    View details for Web of Science ID 000249906900021

    View details for PubMedID 17706797