Bio

Bio


Dr. Chang's clinical practice is based at the Lucile Packard Children's Hospital, and is focused on Pediatric Otology. He has specific clinical interests in congenital hearing loss, congenital ear anomalies, microtia and atresia reconstruction, and pediatric cochlear implantation. His research interests are also in hearing loss, and include neonatal hearing screening, genetics of hearing loss, otoacoustic emissions, auditory physiology, and ototoxicity. He is actively involved in several human clinical trials looking at the prevention of cisplatin ototoxicity that may drastically decrease the number of children developing hearing loss after chemotherapy, and also presented the Chang Ototoxicity Scale in Journal of Clinical Oncology. His current research interests include the radiologic evaluation of congenital inner ear anomalies, and the analysis of how Connexin-based mutations can alter management of infants with congenital hearing loss.

Dr. Chang received his B.A. magna cum laude at Brown University, graduating Phi Beta Kappa. He continued there for his M.D. degree, receiving the Henry Randall Prize and the Sigma Xi Award. He completed his Otolaryngology residency in Seattle, at the University of Washington. This was followed by a fellowship in Pediatric Otolaryngology at the Children's Hospital of Pittsburgh. He joined the faculty at Stanford University in 2000.

Specialties: Pediatric Otology, Auditory Research, Ototoxicity, Pediatric Cochlear Implantation, Microtia Reconstruction, Canal Atresia Reconstruction, Medical Device Research and Development

Clinical Focus


  • Congenital Ear Anomalies
  • Cochlear Implantation
  • Intracapsular Tonsillectomy
  • Otoacoustic Emissions
  • Ototoxicity
  • Pediatric Otolaryngology
  • Cholesteatoma
  • Microtia Reconstruction
  • Ear Canal Atresia
  • Pediatric Otology
  • Cochlear Implants
  • Otoplasty
  • Genetic Hearing Loss
  • Coblation Tonsillectomy
  • Connexin 26
  • Otolaryngology - Head & Neck Surgery (Ear, Nose and Throat)
  • Medical Device Design
  • Congenital Hearing Loss
  • Hearing Loss
  • Otolaryngology

Academic Appointments


Administrative Appointments


  • Editorial Board, Otology Neurotology (2012 - Present)
  • Finance Committee Chair, American Society of Pediatric Otolaryngology (ASPO) (2012 - Present)
  • Editorial Board, Otolaryngology - Head and Neck Surgery (2009 - Present)
  • Ped/OB FPO Finance Committee, LPCH (2005 - Present)
  • Executive Steering Committee, LPCH Enterprise-Wide Scheduling Initiative (2012 - 2014)
  • Advanced Stanford Leadership Development Program, Stanford University (2012 - 2012)
  • Chair, Ototoxicity Consensus Conference, International Society of Pediatric Oncology (SIOP) (2010 - 2010)
  • Stanford Faculty Fellows Program, Stanford University (2009 - 2009)
  • Faculty Senate, Stanford University School of Medicine (2005 - 2008)
  • Policy Committee, LPCH (2004 - 2005)
  • Director of Medical Student Programs, Stanford Otolaryngology (2002 - 2011)
  • Care Improvement Committee, LPCH (2001 - 2011)

Honors & Awards


  • American Otological Society (AOS), - (2014)
  • AAO-HNS Foundation Honor Award, American Acad of Otolaryngology - Head & Neck Surg (2013)
  • Acceptance of Triologic Thesis, Triological Society (2011)
  • Castle Connolly's Top Doctors, Castle Connolly (2012)
  • Top Ten Doctors, Vitals (2012)
  • Patients' Choice Award, - (2011-2012)
  • Resident Teaching Award, Stanford Otolaryngology (2010)
  • Best Doctors in America, Best Doctors (2005)
  • "Excellence in Teaching" award, Stanford University School of Medicine (2004)
  • Resident Teaching Award, Stanford Otolaryngology (2003)
  • Sigma Xi Award, Sigma Xi (1992)
  • Henry Randall Prize, Brown University (1992)
  • Leonard H. Campbell Scholarship, Brown University School of Medicine (1991)
  • Milton Hamolsky Prize, Brown University (1989)
  • Magna Cum Laude, Brown University (1989)
  • Phi Beta Kappa, Phi Beta Kappa (1988)
  • Presidential Scholar, USA (1985)

Boards, Advisory Committees, Professional Organizations


  • Member, American Otological Society (AOS) (2014 - Present)
  • Member, AAO-HNS Hearing Committee (2013 - Present)
  • Chair, ASPO Finance Committee (2012 - Present)
  • Editorial Board, Otology and Neurotology (2012 - Present)
  • Member, Triologic Society (2011 - Present)
  • Editorial Board, Otolaryngology - Head and Neck Surgery (2009 - Present)
  • Member, ASPO Pediatric Otology Study Group (2007 - Present)
  • Member, American Society of Pediatric Otolaryngology (ASPO) (2005 - Present)
  • Member, Society for Ear, Nose and Throat Advances in Children (SENTAC) (2004 - Present)
  • Member, Children’s Oncology Group (COG) (2003 - Present)
  • Member, American Academy of Otolaryngology–Head and Neck Surgery (AAO-HNS) (1994 - Present)
  • Member, AAO-HNS CPT/RVU Committee (2011 - 2014)
  • Member, ASPO Membership Committee (2010 - 2012)
  • Member, ASPO Finance Committee (2010 - 2012)
  • Co-Chair Ototoxicity Consensus Conference, International Society of Pediatric Oncology (SIOP) (2010 - 2010)
  • Elected Member, ASPO Nominating Committee (2009 - 2014)
  • Member, AAO-HNS Pediatric Otolaryngology Committee (2009 - 2011)
  • Member, Association for Research in Otolaryngology (ARO) (1995 - 1998)

Professional Education


  • Fellowship:Children's Hospital of Pittsburgh (2000) PA
  • Board Certification: Otolaryngology, American Board of Otolaryngology (1999)
  • Residency:University of Washington Medical Center (1998) WA
  • Internship:University of Washington Medical Center (1993) WA
  • Medical Education:Brown University - School of Medicine (1992) RI
  • B.A., Brown University, Cognitive Science (1989)

Patents


  • Paul Davison, Kay Chang. "United States Patent 2010/0174283 A1 Electrosurgical devices for tonsillectomy and adenoidectomy", Jan 5, 2009

Research & Scholarship

Current Research and Scholarly Interests


Dr. Chang's research interests include congenital hearing loss, neonatal hearing screening, genetics of hearing loss, otoacoustic emissions, auditory physiology, and ototoxicity. He is actively involved in several human clinical trials looking at the prevention of cisplatin ototoxicity that may drastically decrease the number of children developing hearing loss after chemotherapy, and also presented the Chang Ototoxicity Scale in Journal of Clinical Oncology. His current research interests include the radiologic evaluation of congenital inner ear anomalies, and the analysis of how Connexin-based mutations can alter management of infants with congenital hearing loss.

Teaching

2013-14 Courses


Publications

Journal Articles


  • Concordance between the chang and the International Society of Pediatric Oncology (SIOP) ototoxicity grading scales in patients treated with cisplatin for medulloblastoma. Pediatric blood & cancer Bass, J. K., Huang, J., Onar-Thomas, A., Chang, K. W., Bhagat, S. P., Chintagumpala, M., Bartels, U., Gururangan, S., Hassall, T., Heath, J. A., McCowage, G., Cohn, R. J., Fisher, M. J., Robinson, G., Broniscer, A., Gajjar, A., Gurney, J. G. 2014; 61 (4): 601-605

    Abstract

    Reporting ototoxicity is frequently complicated by use of various ototoxicity criteria. The International Society of Pediatric Oncology (SIOP) ototoxicity grading scale was recently proposed for standardized use in reporting hearing loss outcomes across institutions. The aim of this study was to evaluate the concordance between the Chang and SIOP ototoxicity grading scales. Differences between the two scales were identified and the implications these differences may have in the clinical setting were discussed.Audiological evaluations were reviewed for 379 patients with newly diagnosed medulloblastoma (ages 3-21 years). Each patient was enrolled on one of two St. Jude clinical protocols that included craniospinal radiation therapy and four courses of 75 mg/m(2) cisplatin chemotherapy. The latest audiogram conducted 5.5-24.5 months post-protocol treatment initiation was graded using the Chang and SIOP ototoxicity criteria. Clinically significant hearing loss was defined as Chang grade ≥2a and SIOP ≥2. Hearing loss was considered serious (requiring a hearing aid) at the level of Chang grade ≥2b and SIOP ≥3.A strong concordance was observed between the Chang and SIOP ototoxicity scales (Stuart's tau-c statistic = 0.89, 95% CI: 0.86, 0.91). Among those patients diagnosed with serious hearing loss, the two scales were in good agreement. However, the scales deviated from one another in classifying patients with less serious or no hearing loss.Although discrepancies between the Chang and SIOP ototoxicity scales exist primarily for patients with no or minimal hearing loss, the scales share a strong concordance overall. Pediatr Blood Cancer 2014;61:601-605. © 2013 Wiley Periodicals, Inc.

    View details for DOI 10.1002/pbc.24830

    View details for PubMedID 24504791

  • GJB2-Associated Hearing Loss: Systematic Review of Worldwide Prevalence, Genotype, and Auditory Phenotype LARYNGOSCOPE Chan, D. K., Chang, K. W. 2014; 124 (2): E34-E53

    Abstract

    To perform a systematic review of GJB2-associated hearing loss to describe genotype distributions and auditory phenotype.230 primary studies identified from Pubmed.Pubmed was searched systematically to screen broadly for any study reporting on genotype and carrier frequencies for biallelic GJB2-associated hearing loss in defined populations around the world. Genotype and audiometric data were extracted and subjected to meta-analysis to determine genotype distributions, carrier frequencies, rates of asymmetric or progressive hearing loss, and imaging abnormalities.A total of 216 articles comprising over 43,000 hearing-loss probands were included. The prevalence of biallelic GJB2-associated hearing loss was consistent across most of the 63 countries examined, with different mutations being predominant in different countries. Common mutations were found in greater than 3% of the general population worldwide. Meta-analysis of 48 case-control studies demonstrated a two-fold higher carrier frequency among hearing-impaired individuals compared to normal-hearing controls for truncating alleles, but not V37I. Progression, asymmetry, and imaging abnormalities were present in 14% to 19% of individuals with GJB2-associated hearing loss.GJB2 mutations are highly prevalent around the world. The multiple predominant mutations present in different populations attest to the importance of this gene for normal cochlear function and suggests an evolutionary heterozygote advantage. The unusually high carrier rate for truncating mutations among hearing-impaired individuals is consistent with either the presence of complementary mutations or a carrier phenotype. The significant rate of asymmetry and progression highlights the importance of diagnostic workup and close follow-up for this highly variable condition. Laryngoscope, 124:E34-E53, 2014.

    View details for DOI 10.1002/lary.24332

    View details for Web of Science ID 000329929900003

    View details for PubMedID 23900770

  • The proximal bronchoplasty retrieval technique for removal of embedded distal airway foreign bodies INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Hoff, S. R., Chang, K. W. 2014; 78 (1): 148-151

    Abstract

    To describe a novel technique for removal of embedded distal airway foreign bodies with emphasis on procedural steps and management.The proximal bronchoplasty retrieval (PBR) technique is described including indications, rationale, surgical technique, and clinical decision making. Two representative cases are described in detail in order to demonstrate the technique.The PBR technique was successfully used to remove the two described embedded distal airway foreign bodies after other attempts had failed.Airway foreign bodies which have been present for several days or weeks are associated with edema and granulation tissue which often embeds the foreign body and may prevent removal due to proximal airway narrowing. We present a novel technique using endoscopic balloon dilation bronchoplasty to enlarge the airway proximal to the foreign body and enable removal with two example cases presented herein. The PBR technique allowed for removal of otherwise "stuck" distal airway foreign bodies.

    View details for DOI 10.1016/j.ijporl.2013.10.051

    View details for Web of Science ID 000329959100032

    View details for PubMedID 24315084

  • Hearing outcomes of atresia surgery versus osseointegrated bone conduction device in patients with congenital aural atresia: a systematic review. Otology & neurotology Nadaraja, G. S., Gurgel, R. K., Kim, J., Chang, K. W. 2013; 34 (8): 1394-1399

    Abstract

    To perform a systematic review, comparing hearing outcomes of atresiaplasty versus osseointegrated bone conduction device (OBCD) in congenital aural atresia (CAA) patients.Approximately 107 studies, published from 1975 to 2012, evaluating hearing outcomes after atresiaplasty and/or OBCD in CAA patients were identified through a PubMed search.Articles that evaluated external auditory canal stenosis alone, did not report speech reception threshold (SRT), pure tone average (PTA), hearing gain, or air-bone gap (ABG) or had less than 5 patients were excluded. For authors or institutions with multiple reports, the largest or most recent study was included. Forty-one articles satisfied our inclusion and exclusion criteria.The number and percentage of ears with a postoperative SRT, PTA, ABG less than 30 dB, and/or average hearing gain were extracted. The total number of ears and the timing of the postoperative audiogram were also noted.Of the atresiaplasty ears, 73.8% (95% CI, 62.2%-85.4%), had a SRT less than 30 dB (338 ears), 60.3% (95% CI, 45.8%-74.8%) had a PTA less than 30 dB (390 ears), and 68.9% (95% CI, 59.4%-78.3%) had an ABG less than 30 dB (852 ears). The average hearing gain was 24.1 dB (95% CI, 21.62-26.51) for 516 ears. Hearing outcomes deteriorated with time. Of OBCD patients, 95.9% (95% CI, 91.5%-100.0%) had a PTA less than 30 dB (77 ears), and 98.2% (95% CI, 94.5%-100.0%) had an ABG less than 30 dB (47 ears); the average hearing gain was 38.0 dB (95% CI, 33.14-45.22) in 100 ears.The OBCD has better hearing outcomes compared with atresiaplasty in patients with CAA.

    View details for DOI 10.1097/MAO.0b013e3182a36065

    View details for PubMedID 24005171

  • Lip Abscess Associated With Isotretinoin Treatment of Acne Vulgaris JAMA DERMATOLOGY Huoh, K. C., Chang, K. W. 2013; 149 (8): 960-961

    Abstract

    IMPORTANCE Isotretinoin is frequently prescribed for the treatment of acne vulgaris. Among the numerous documented adverse effects, most common are xerostomia and cheilitis. Lip abscesses as a consequence of cheilitis present dramatically and may pose a diagnostic challenge. OBSERVATIONS We present a case of a 15-year-old boy with a severe lip abscess requiring incision and drainage and hospital admission for intravenous antibiotic treatment of methicillin-resistant Staphylococcus aureus. We discuss the pathophysiologic characteristics of isotretinoin therapy and the likely causative role that the medication played in the development of the lip abscess. CONCLUSIONS AND RELEVANCE Although rare, lip abscesses related to isotretinoin therapy present with substantial morbidity and should be promptly recognized. Misdiagnosis of mucositis and angioedema may delay appropriate therapy.

    View details for DOI 10.1001/jamadermatol.2013.4066

    View details for Web of Science ID 000323721400016

    View details for PubMedID 23760516

  • 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

    Abstract

    Propranolol has recently emerged as an effective therapy for infantile hemangiomas causing regression. The ?-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 ?2-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 ?ARs 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 ?3-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 ?-AR expression in a variety of vascular lesions. Although immunohistochemical expression of the receptors does not necessarily indicate that similar pathways of responsiveness to ?-blockade are present, it does raises the possibility that ?-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

  • Platinum-Induced Ototoxicity in Children: A Consensus Review on Mechanisms, Predisposition, and Protection, Including a New International Society of Pediatric Oncology Boston Ototoxicity Scale JOURNAL OF CLINICAL ONCOLOGY Brock, P. R., Knight, K. R., Freyer, D. R., Campbell, K. C., Steyger, P. S., Blakley, B. W., Rassekh, S. R., Chang, K. W., Fligor, B. J., Rajput, K., Sullivan, M., Neuwelt, E. A. 2012; 30 (19): 2408-2417

    Abstract

    The platinum chemotherapy agents cisplatin and carboplatin are widely used in the treatment of adult and pediatric cancers. Cisplatin causes hearing loss in at least 60% of pediatric patients. Reducing cisplatin and high-dose carboplatin ototoxicity without reducing efficacy is important.This review summarizes recommendations made at the 42nd Congress of the International Society of Pediatric Oncology (SIOP) in Boston, October 21-24, 2010, reflecting input from international basic scientists, pediatric oncologists, otolaryngologists, oncology nurses, audiologists, and neurosurgeons to develop and advance research and clinical trials for otoprotection.Platinum initially impairs hearing in the high frequencies and progresses to lower frequencies with increasing cumulative dose. Genes involved in drug transport, metabolism, and DNA repair regulate platinum toxicities. Otoprotection can be achieved by acting on several these pathways and generally involves antioxidant thiol agents. Otoprotection is a strategy being explored to decrease hearing loss while maintaining dose intensity or allowing dose escalation, but it has the potential to interfere with tumoricidal effects. Route of administration and optimal timing relative to platinum therapy are critical issues. In addition, international standards for grading and comparing ototoxicity are essential to the success of prospective pediatric trials aimed at reducing platinum-induced hearing loss.Collaborative prospective basic and clinical trial research is needed to reduce the incidence of irreversible platinum-induced hearing loss, and optimize cancer control. Wide use of the new internationally agreed-on SIOP Boston ototoxicity scale in current and future otoprotection trials should help facilitate this goal.

    View details for DOI 10.1200/JCO.2011.39.1110

    View details for Web of Science ID 000306182300020

    View details for PubMedID 22547603

  • Is It Valid to Calculate the 3-Kilohertz Threshold by Averaging 2 and 4 Kilohertz? OTOLARYNGOLOGY-HEAD AND NECK SURGERY Gurgel, R. K., Popelka, G. R., Oghalai, J. S., Blevins, N. H., Chang, K. W., Jackler, R. K. 2012; 147 (1): 102-104

    Abstract

    Many guidelines for reporting hearing results use the threshold at 3 kilohertz (kHz), a frequency not measured routinely. This study assessed the validity of estimating the missing 3-kHz threshold by averaging the measured thresholds at 2 and 4 kHz. The estimated threshold was compared to the measured threshold at 3 kHz individually and when used in the pure-tone average (PTA) of 0.5, 1, 2, and 3 kHz in audiometric data from 2170 patients. The difference between the estimated and measured thresholds for 3 kHz was within ± 5 dB in 72% of audiograms, ± 10 dB in 91%, and within ± 20 dB in 99% (correlation coefficient r = 0.965). The difference between the PTA threshold using the estimated threshold compared with using the measured threshold at 3 kHz was within ± 5 dB in 99% of audiograms (r = 0.997). The estimated threshold accurately approximates the measured threshold at 3 kHz, especially when incorporated into the PTA.

    View details for DOI 10.1177/0194599812437156

    View details for Web of Science ID 000314267600018

    View details for PubMedID 22301102

  • CT Analysis Demonstrates That Cochlear Height Does Not Change with Age AMERICAN JOURNAL OF NEURORADIOLOGY Mori, M. C., Chang, K. W. 2012; 33 (1): 119-123

    Abstract

    CH measurements can often be useful in the diagnosis of inner ear malformations associated with SNHL. Our aim was to establish the relationship between CH and age by using analysis of CT images in patients who underwent coronal CT scans of the temporal bone between 2001 and 2007.We measured CH on coronal CT scans of the temporal bone of 422 ears scanned from 2001 to 2007 in 211 patients, 1 month to 23 years of age. Using multivariate linear regression analysis, we determined the relationship of CH to age, sex, and HL type. In addition, 11 patients with multiple scans at different ages were assessed for change in CH with age.Average CH was 5.3 mm (normal range, 4.4-6.2 mm). Analysis showed no statistically significant change in CH across ages from 1 month to 23 years (95% CI for regression line slope = -0.003, 0.013). Likewise, there were no statistically significant differences in CH for patients with multiple scans at different ages. ICW increased with age as expected with increased cranial size. A small difference in CH between sexes was noted with males having greater CHs than females (P < .01). All patients with hypoplastic cochleas, defined by a CH <2 SDs from the mean (4.48 mm for males and 4.25 mm for females), had HL with a positive predictive value of 86%.CH does not change from 1 month of age to adulthood and is slightly greater in males than in females.

    View details for DOI 10.3174/anjr.A2713

    View details for Web of Science ID 000299491400020

    View details for PubMedID 21960502

  • Clinically Accurate Assessment and Grading of Ototoxicity LARYNGOSCOPE Chang, K. W. 2011; 121 (12): 2649-2657

    Abstract

    To design a grading scale and audiologic protocols to better reflect clinical impact than the currently widely used classifications.Retrospective.Audiologic studies from 130 patients receiving cisplatin chemotherapy were analyzed. Pure-tone audiograms were evaluated using the newly proposed grading criteria, Brock criteria, and Common Terminology Criteria for Adverse Events (CTCAE). The resulting grades were then compared to recommended audiologic interventions. Auditory brainstem response (ABR) data and data on incidences of conductive hearing loss from other multi-institutional studies that the author participated in were compared to data from this cohort.Although the newly proposed, Brock, and CTCAE ototoxicity grades were significantly related to audiologist recommendations for assistive devices (P < .0001), the newly proposed criteria were more specific and allowed better delineation of different patients into distinct subgroups requiring either FM system (grade 2a) or hearing aid (grade 2b or higher). Multi-institutional data review indicated significant problems with ABR evaluations and separating out conductive hearing losses from ototoxicity.The newly proposed grading system needs to be paired with specific recommendations regarding audiologic monitoring protocols as well as active participation by the audiologists implementing the protocol to provide clinically accurate assessment and grading of ototoxicity.

    View details for DOI 10.1002/lary.22376

    View details for Web of Science ID 000297644000025

    View details for PubMedID 22109766

  • Diagnostic Yield in the Workup of Congenital Sensorineural Hearing Loss Is Dependent on Patient Ethnicity OTOLOGY & NEUROTOLOGY Chan, D. K., Schrijver, I., Chang, K. W. 2011; 32 (1): 81-87

    Abstract

    Diagnostic yield on GJB2 sequencing and computed tomography in the workup for idiopathic congenital sensorineural hearing loss is related to patient ethnicity.GJB2 sequencing and computed tomography of the temporal bones are important initial diagnostic tests in the workup of idiopathic congenital sensorineural hearing loss. Previous studies showed an association between mild or unilateral hearing loss and positive imaging findings and between severe or bilateral deafness and GJB2 mutations. Recent studies on connexin 26-associated deafness demonstrate a wide range of phenotypes that vary with ethnicity.We present a retrospective case series of 271 consecutive ethnically diverse patients evaluated for idiopathic congenital sensorineural hearing loss. Results of genetic testing and imaging were correlated with audiologic findings and ethnicity.All patients with asymmetric hearing loss had more positive findings on imaging. With respect to the severity of hearing loss, however, differences were noted between ethnic groups. Whereas white patients conformed to previous findings, Hispanics with severe hearing loss had similar rates of positive imaging and genetic testing results. Asians with mild hearing loss had significantly greater yield on genetic testing rather than on imaging. This reflects the high prevalence of the p.V37I mutation in GJB2 among Asians, which gives rise to a mild, frequently progressive phenotype.Ethnicity should be considered when determining the optimal sequence of diagnostic testing for idiopathic congenital sensorineural hearing loss. Asian patients, in particular, should all be screened for mutations in GJB2, especially in the case of mild hearing loss.

    View details for DOI 10.1097/MAO.0b013e3181fc786f

    View details for Web of Science ID 000285334400019

    View details for PubMedID 21042228

  • 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

    Abstract

    (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

  • Practical Grading System for Evaluating Cisplatin Ototoxicity in Children JOURNAL OF CLINICAL ONCOLOGY Chang, K. W., Chinosornvatana, N. 2010; 28 (10): 1788-1795

    Abstract

    We present a new ototoxicity grading system that has clearly defined and frequency-specific audiometric criteria. The purpose of this study was to validate this grading system by assessing its correspondence to audiology treatment recommendations and comparing it with the currently utilized Common Terminology Criteria for Adverse Events (CTCAE).A retrospective chart review was conducted using audiologic, demographic, and clinical data from 134 children receiving 149 courses of chemotherapy consisting of cisplatin and/or carboplatin. Pure-tone audiograms were evaluated using both our proposed grading criteria and the CTCAE criteria. The resulting grades were then compared with charted audiologic interventions and a number of clinical parameters to assess the clinical validity of the grading scale.Chang grade 2a or higher predicted audiologic intervention. Although both the Chang and CTCAE ototoxicity grades were significantly related to audiologist recommendations for assistive devices such as hearing aids and/or frequency modulated systems (P < .0001), the Chang scale was more specific, with the CTCAE scale diverging from clinical recommendation at higher grades. As expected, patients receiving cisplatin had more severe hearing loss with concurrent carboplatin administration, radiation therapy exposure, younger age, smaller body-surface area, longer treatment exposure, and more severe disease.This grading system provides robust and clinically useful criteria to represent clinical hearing loss induced by ototoxicity with regard to the impact on speech and language and the need for assistive hearing devices. It is both more specific and more sensitive than the traditional CTCAE criteria for identifying clinically significant ototoxicity.

    View details for DOI 10.1200/JCO.2009.24.4228

    View details for Web of Science ID 000276152200027

    View details for PubMedID 20194861

  • Connexin-26-associated deafness: Phenotypic variability and progression of hearing loss GENETICS IN MEDICINE Chan, D. K., Schrijver, I., Chang, K. W. 2010; 12 (3): 174-181

    Abstract

    To evaluate genotype-phenotype correlation over time for a cohort of children with connexin-26 (GJB2)-associated autosomal recessive hearing loss.Fifty-two children were identified from a database of individuals with homozygous or compound heterozygous mutations in GJB2 and subjected to chart review of their otolaryngologic and serial audiometric evaluations. Genotype-phenotype correlations were identified among the members of this group by appropriate statistical analyses.Hearing loss was most severe in individuals with two truncating mutations in GJB2 and mildest in those with two nontruncating mutations. Progressive hearing loss was seen directly by serial audiometry in 24% of all subjects, and suggested in a total of 28% when those with normal newborn hearing screens and subsequent hearing loss were included. Progression was particularly common among carriers of the p.V37I allele either in homozygosity or in compound heterozygosity with a truncating allele; these children are primarily of Asian descent and demonstrate mild, slowly progressive hearing loss.Phenotype in GJB2-associated hearing loss is correlated with genotype, with truncating mutations giving rise to more severe hearing loss. Progression of hearing loss is not uncommon, especially in association with the p.V37I allele. These results suggest that close audiometric follow-up is warranted for patients with GJB2-associated recessive hearing loss.

    View details for DOI 10.1097/GIM.0b013e3181d0d42b

    View details for Web of Science ID 000276023100007

    View details for PubMedID 20154630

  • 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

    Abstract

    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

  • Amifostine Does Not Prevent Platinum-Induced Hearing Loss Associated With the Treatment of Children With Hepatoblastoma CANCER Katzenstein, H. M., Chang, K. W., Krailo, M., Chen, Z., Finegold, M. J., Rowland, J., Reynolds, M., Pappo, A., London, W. B., Malogolowkin, M. 2009; 115 (24): 5828-5835

    Abstract

    The current study was conducted to determine whether amifostine is effective in reducing the toxicities associated with the administration of platinum-containing regimens in children with hepatoblastoma (HB).Patients were enrolled on P9645 beginning in March of 1999. Patients who had stage I/II disease received treatment with 4 cycles of combined cisplatin, 5-fluorouracil, and vincristine (C5V) with or without amifostine. Patients who had stage III/IV disease were randomized to receive treatment with 6 cycles of either C5V with or without amifostine or carboplatin alternating with cisplatin (CC) with or without amifostine. Patients who were randomized to receive amifostine were given a dose of 740 mg/m2 intravenously over 15 minutes before each administration of a platinum agent.Eighty-two patients were considered in a special interim analysis of the incidence of toxicity. The disease outcome for patients who received amifostine was similar to the outcome for patients who did not receive amifostine (P=.22). The incidence of significant hearing loss (>40 dB) was similar for patients who did or did not receive amifostine (38% [14 of 37 patients] vs 38% [17 of 45 patients], respectively; P=.68). There were no differences in the incidence of renal or bone marrow toxicities evaluated. Patients who received amifostine had a higher incidence of hypocalcemia (5% vs 0.5%; P=.00006).Amifostine in the doses and schedule used in this study failed to significantly reduce the incidence of platinum-induced toxicities in patients with HB.

    View details for DOI 10.1002/cncr.24667

    View details for Web of Science ID 000272545400028

    View details for PubMedID 19813275

  • Otorrhea in Infants With Tympanostomy Tubes Before and After Surgical Repair of a Cleft Palate ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY Curtin, G., Messner, A. H., Chang, K. W. 2009; 135 (8): 748-751

    Abstract

    To compare the incidence of otorrhea in a group of infants with cleft palate (CP) and tympanostomy tubes before and after surgical repair of the CP.Prospective observational study.Otolaryngology clinic at a tertiary care children's hospital.Thirty-three infants with CP and middle ear effusions who underwent tympanostomy tube placement. Subjects were observed from the time of tube placement until 6 months after CP repair.Incidence of otorrhea before and after CP repair.Subjects were observed a mean of 6.3 months before CP repair and 6 months after CP repair. Before CP repair, 11 of 33 infants (33%) had no episodes of otorrhea, compared with 22 of 33 (67%) after CP repair (P = .007). Fourteen infants (43%) had 2 or more episodes of otorrhea before CP repair compared with 2 (6%) after CP repair (P = .001). Before CP repair, significantly fewer tubes were patent at the time of the audiologic evaluation compared with after CP repair (39 of 62 [63%] vs 52 of 66 [79%]; P = .048). Average speech reception threshold for the infants with tympanostomy tubes before CP repair was 18.1 dB compared with 12.6 dB after CP repair (P = .01).The incidence of otorrhea after tympanostomy tube placement before CP repair is higher than the incidence after CP repair, although more than half of all infants (19 [58%]) had either 1 or no episodes of otorrhea before CP repair.

    View details for Web of Science ID 000269022600003

    View details for PubMedID 19687392

  • Evaluation of unilateral referrals on neonatal hearing screening JOURNAL OF MEDICAL SCREENING Chang, K. W., O-Lee, T. J., Price, M. 2009; 16 (1): 17-21

    Abstract

    Examination of neonatal hearing screening practices around the world suggests that more attention is placed on infants who fail bilaterally on their hearing screen than infants who refer (fail) in one ear. Some programmes only report bilateral failures as positive hearing screens. This study investigates how limitations of the screening techniques demand continued audiologic evaluations in unilateral referrals.The study sample consisted of all infants born at a single academic paediatric hospital between February 1998 and February 2002.There were 16,007 infants screened using ALGO automated auditory brainstem response. Eighteen of the infants who failed the screen in one ear but passed in the other ear were found to have permanent hearing loss, and had their subsequent clinical course and audiologic management analysed. The final audiologic outcome after four years in both the pass and fail ear were examined.One group of unilateral referrals (n = 6) had obvious anatomic reasons for the ear failing the screen (canal atresia/stenosis). There were five patients in which the ear that passed the screen was later found on more extensive audiologic evaluation to have significant hearing loss. Review of recent literature was also completed to examine the methods by which unilateral screening referrals are commonly reported and whether or not this affected follow-up diagnostic evaluation.Infants who pass one ear and refer one ear on neonatal hearing screening still need to have thorough and prompt evaluations. In many cases, the ear that passed can be found to have significant hearing loss.

    View details for DOI 10.1258/jms.2009.007113

    View details for Web of Science ID 000266114400004

    View details for PubMedID 19349526

  • Intracapsular versus subcapsular coblation tonsillectomy OTOLARYNGOLOGY-HEAD AND NECK SURGERY Chang, K. W. 2008; 138 (2): 153-157

    Abstract

    To compare the postoperative recovery of patients who undergo intracapsular to subcapsular Coblation tonsillectomy.This was a prospective, randomized, double-blinded study. A total of 69 children, aged 2 to 16 years, were randomized to intracapsular (n = 34) or subcapsular (n = 35) tonsillectomy. The Coblation technique was used with both groups. Outcomes measures were assessed on postoperative day 1 or 2 and 5 or 6. These included child and parental rating of pain with the Wong Faces pain scale, analgesic use, oral intake, and activity level.Intracapsular tonsillectomy patients had similar levels of pain to subcapsular tonsillectomy patients on day 1 or 2. However, at day 5 or 6, intracapsular tonsillectomy patients had significantly less pain than the subcapsular tonsillectomy patients. Intracapsular patients ate more and were more active at both time points.Children with obstructive sleep apnea who undergo tonsillectomy demonstrate better postoperative recovery after intracapsular tonsillectomy. The intracapsular versus subcapsular difference may be best appreciated at a delayed time point (day 5 or 6) rather than early (day 1 or 2).

    View details for DOI 10.1016/j.otohns.2007.11.006

    View details for Web of Science ID 000252963100005

    View details for PubMedID 18241707

  • Utility of temporal bone computed tomographic measurements in the evaluation of inner ear malformations ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY Chen, J. L., Gittleman, A., Barnes, P. D., Chang, K. W. 2008; 134 (1): 50-56

    Abstract

    To investigate whether normative inner ear measurements can assist in the evaluation of sensorineural hearing loss (SNHL).Retrospective cohort review.A tertiary care hospital.Computed tomography or magnetic resonance imaging was performed on 188 ears with SNHL and 220 ears without SNHL (204 children) between 2001 and 2004.Two readers measured the basal turn of cochlea (BTC) lumen, lateral semicircular canal (LSCC) bony island width, superior semicircular canal (SSCC) bony island width, and cochlear height (CH).A t test was performed comparing measurements in patients with and without SNHL. Interobserver variability was characterized by intraclass correlation coefficients and Bland-Altman plots.The t test results demonstrated no statistically significant differences between inner ear measurements in those with and without SNHL. The intraclass correlation coefficients for BTC lumen, CH, LSCC bony island width, and SSCC bony island width measurements was 0.612, 0.632, 0.869, and 0.912, respectively. Bland-Altman plots revealed systematic biases of 1%, 8%, 10%, and 21% for the BTC lumen, SSCC bony island width, LSCC bony island width, and CH measurements, respectively.Inner ear measurements in children with and without SNHL are not statistically different. Moreover, the measurements are difficult to interpret because while they demonstrate good reproducibility, they are susceptible to systematic biases. However, use of inner ear measurements is more sensitive in identifying vestibulocochlear dysplasias and should be considered to complement visual analysis.

    View details for Web of Science ID 000252313300010

    View details for PubMedID 18209137

  • Recovery from cisplatin-induced ototoxicity. Int J Pediatr Otorhinolaryngol Truong, M. T., Winzelberg, J., Chang, K. W. 2007; 71 (10): 1631-8
  • Two patients with the V371/235delC genotype: Are radiographic cochlear anomalies part of the phenotype? INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Schrijver, I., Chang, K. W. 2006; 70 (12): 2109-2113

    Abstract

    We present two East Asian patients with sensorineural hearing loss (SNHL) and compound heterozygosity for the 235delC and V37I mutations in the GJB2 gene. One patient has a unilaterally enlarged vestibular aqueduct, which underscores the importance of routine CT examination in children with SNHL, even if GJB2 (connexin 26) mutations have been identified. The second patient was not available for evaluation by CT. The pathogenic role of the V37I mutation has been controversial. We review the literature and present evidence in support of pathogenicity. Larger studies in compound heterozygous individuals and co-transfection studies will allow better genotype-phenotype correlations and prognostication.

    View details for DOI 10.1016/j.ijporl.2006.07.015

    View details for Web of Science ID 000242707900015

    View details for PubMedID 16952406

  • Amifostine does not protect against the ototoxicity of high-dose cisplatin combined with etoposide and bleomycin in pediatric germ-cell tumors - A children's Oncology Group study CANCER Marina, N., Chang, K. W., Malogolowkin, M., London, W. B., Frazier, A. L., Womer, R. B., Rescorla, F., Billmire, D. F., DAVIS, M. M., Perlman, E. J., Giller, R., Lauer, S. J., Olson, T. A. 2005; 104 (4): 841-847

    Abstract

    High-dose cisplatin combined with etoposide and bleomycin (HDPEB) improves event-free survival (EFS) in advanced pediatric germ-cell tumors (PGCT), but has significant ototoxicity. Amifostine appears to protect against toxicity. The authors combined amifostine with HDPEB and evaluated the efficacy and toxicity, specifically whether ototoxicity decreased.Eligibility criteria included age < 15 years and unresectable Stage III/IV extracranial, extragonadal PGCT. Patients received bleomycin 15 IU/m(2) on Day 1, then etoposide 100 mg/m(2) per day, amifostine 825 mg/m(2) per day, and cisplatin 40 mg/m(2)per day on Days 1-5, intravenously. The cycles were repeated every 3-4 weeks with imaging evaluation after 4 cycles. Patients with residual radiographic abnormalities underwent resection. Patients with residual tumor received two additional HDPEB cycles. Hearing evaluations were required at diagnosis and after two and four cycles. Audiologic results were reviewed and compared with historical controls treated with HDPEB.Twenty-five eligible patients were enrolled between April 2000 and April 2002. Their median age was 1.6 years (range, 0.64-13.9 years), 17 patients were female, 11 had metastases, and 24 had a yolk sac carcinoma component histologically. Primary sites included sacrococcygeal area/pelvis (n = 15), vagina (n = 5), and other (n = 5). Two-year EFS and overall survival were 83.5% +/- 12.8% and 85.6% +/- 12.3%, respectively. Eight patients were removed from the study (four had progressive disease/disease recurrence and four had ototoxicity). Grade 3/4 toxicities included neutropenia (n = 20), thrombocytopenia (n = 14), electrolyte imbalances (n = 14), and gastrointestinal toxicity (n = 12). Twenty-four of 25 patients received hearing evaluations, and 75% had significant hearing loss.Amifostine did not protect against HDPEB-associated ototoxicity.

    View details for DOI 10.1002/cncr.21218

    View details for Web of Science ID 000231040500023

    View details for PubMedID 15999362

  • Not your routine foreign body: Endobronchial tuberculosis in an infant PEDIATRICS Agarwal, S., Hong, D. K., Soslow, J., Chang, K. W. 2005; 116 (1): 246-248

    Abstract

    Foreign-body aspiration is a common cause of respiratory distress among children. Here we describe an 8-month-old, previously 34-week premature, male patient who presented with a 1-day history of fever and increased work of breathing. Of note, 3 weeks before presentation, the patient had been treated with orally administered amoxicillin for presumed pneumonia and exhibited good clinical response. No chest radiograph was obtained at that time. A current chest radiograph revealed hyperexpansion of the left lung, with a mediastinal shift. Although the patient was referred because of possible foreign-body aspiration, no clear history of an aspiration event was obtained, and computed tomographic scans of the chest were recommended. These showed extensive hilar and mediastinal lymphadenopathy, resulting in obstruction of the left bronchus. Bronchoscopy revealed a cheesy granulomatous mass in the left mainstem bronchus, which was ball-valving into the upper bronchus. Removal resulted in improvement of the patient's respiratory status. Pathology, bronchial lavage, and gastric aspirate specimens all revealed acid-fast bacilli, consistent with Mycobacterium tuberculosis infection. This unusual presentation of tuberculosis may become more common in the United States as the incidence of immigrants carrying tuberculosis increases.

    View details for Web of Science ID 000230207500065

    View details for PubMedID 15995065

  • Randomized controlled trial of Coblation versus electrocautery tonsillectomy OTOLARYNGOLOGY-HEAD AND NECK SURGERY Chang, K. W. 2005; 132 (2): 273-280

    Abstract

    To compare the postoperative recovery of patients receiving Coblation-assisted (Arthrocare, Sunnyvale, CA) intracapsular tonsillectomy with that of patients receiving traditional subcapsular electrocautery tonsillectomy.This was a prospective, randomized, double-blinded, controlled study. One hundred one children, aged 2 to 16 years, were randomized to Coblation or to conventional electrocautery tonsillectomy. Only patients with the operative indication of obstructive sleep apnea were entered into the study. Intracapsular tonsillectomy was performed on the Coblation group, and traditional subcapsular dissection was performed on the electrocautery group. Adenoidectomy was performed with the curette in both groups. Outcome measures were assessed on days 1, 3, and 5 after surgery. These included child and parental rating of pain by using the Wong Faces pain scale, analgesic use, oral intake, and activity level. Patients, parents, and the nurse practitioner obtaining the outcome data were blinded to treatment arm.Treatment groups were similar in age, gender, and weight. Surgical time and estimated blood loss were similar. There were no complications in either group. Coblation patients had less pain and greater oral intake at all 3 time points. Percentage of normal activity level returned to >70% earlier and more frequently in Coblation patients. There was slightly decreased analgesic use on postoperative day 5 in the Coblation group.Children with obstructive sleep apnea undergoing tonsillectomy and adenoidectomy demonstrate significantly better postoperative recovery after Coblation-assisted intracapsular tonsillectomy.

    View details for Web of Science ID 000226788200020

    View details for PubMedID 15692541

  • Prevention of cisplatin ototoxicity using transtympanic N-acetylcysteine and lactate OTOLOGY & NEUROTOLOGY Choe, W. T., Chinosornvatana, N., Chang, K. W. 2004; 25 (6): 910-915

    Abstract

    Transtympanic administration of the antioxidant N-acetylcysteine or lactated Ringer's solution onto the round window membrane will prevent cisplatin ototoxicity in the guinea pig model.Cochlear ototoxicity is a well-known side effect of cisplatin administration, with the mechanism of injury thought to rest in oxidative damage to the outer hair cells. However, previous attempts at transtympanic antioxidant delivery have met with varied success. We present an effective method of counteracting cisplatin ototoxicity via the transtympanic application of lactated Ringer's solution or N-acetylcysteine.Baseline distortion product otoacoustic emission measurements were obtained. Intraperitoneal cisplatin was administered to a cumulative dose of 20 mg/kg. The middle ears were either untreated (control) or filled with normal saline (negative control), 2%N-acetylcysteine diluted in normal saline (treatment), or lactated Ringer's solution (treatment) via anterosuperior quadrant myringotomies. Posttreatment distortion product otoacoustic emissions were obtained.Animals in the untreated control group and the negative control normal saline group demonstrated consistent obliteration of distortion product otoacoustic emissions. However, those receiving either lactated Ringer's solution or 2%N-acetylcysteine diluted in normal saline demonstrated significant preservation of distortion product otoacoustic emissions. The treatment regimen was well tolerated, with minimal animal loss.We have demonstrated the efficacy of transtympanic lactated Ringer's solution and N-acetylcysteine in the prevention of cisplatin ototoxicity using a guinea pig model. The possible mechanisms for the high efficacy of lactated Ringer's solution are discussed in detail.

    View details for Web of Science ID 000225048700009

    View details for PubMedID 15547419

  • A randomized study of platinum-based chemotherapy with or without amifostine for the treatment of children with hepatoblastoma: A report of the Intergroup Hepatoblastoma Study P9645. Proc Am Soc Clin Oncol Katzenstein HM, Chang K, Krailo M, et al 2004; 22: 8518
  • Pediatric residents' clinical diagnostic accuracy of otitis media PEDIATRICS Steinbach, W. J., Sectish, T. C., Benjamin, D. K., Chang, K. W., Messner, A. H. 2002; 109 (6): 993-998

    Abstract

    Pediatric resident physicians' clinical diagnostic accuracy of otitis media is unknown. We attempted to correlate the clinical examination of pediatric house staff with pediatric otolaryngologists and tympanometry.Pediatric residents evaluated patients who were scheduled in the pediatric acute care clinic and completed a provider examination form detailing their otoscopic findings, interpretation, and treatment plan. Patients were then immediately reevaluated by a pediatric otolaryngologist using an identical form. Tympanometry was also performed by a pediatric audiologist. We used kappa statistics to calculate correlation of clinical findings and interpretation.A total of 103 patients consented for the study; 70 patients were examined by 27 different pediatric residents with 43 patients (86 ears) examined by all 3 providers. Correlation of clinical findings between all pediatric residents and the pediatric otolaryngologists was a kappa statistic of 0.30 (fair agreement). The individual diagnostic finding with the greatest correlation was tympanic membrane erythema (kappa statistic: 0.40 [fair agreement]), and the worst correlate was tympanic membrane position (kappa statistic: 0.16 [slight agreement]). Resident interpretation and tympanometry yielded a kappa statistic of 0.20 (slight agreement), and the otolaryngologist interpretation and tympanometry yielded a kappa statistic of 0.32 (fair agreement).Otitis media is the most common disease seen by practicing general pediatricians, but there is a paucity of formalized resident education. We demonstrated only a slight to moderate correlation between the clinical diagnostic examinations of pediatric residents and pediatric otolaryngologists and tympanometry.

    View details for Web of Science ID 000175907100015

    View details for PubMedID 12042534

  • Efferently mediated changes in the quadratic distortion product (f2-f1) JOURNAL OF THE ACOUSTICAL SOCIETY OF AMERICA Chang, K. W., Norton, S. J. 1997; 102 (3): 1719-1733
  • The effects of continuous versus interrupted noise exposures on distortion product otoacoustic emissions in guinea pigs HEARING RESEARCH Chang, K. W., Norton, S. J. 1996; 96 (1-2): 1-12

    Abstract

    Distortion product otoacoustic emissions (DPOAE) were measured serially in guinea pigs before and following 4-h exposures to a half-octave band of noise centered at 6 kHz. Stimulus parameters used to elicit the DPOAE were f2/f1 = 1.26 and L2 = L1-10. The 80 dB SPL exposures resulted in attenuation of emissions, which was maximal at the frequency one-half octave above the exposure when referenced to the f2 stimulus, and which recovered back to baseline after 2 days. The 90 dB SPL exposures resulted in a permanent deficit in emissions elicited by high-frequency stimuli, as measured after 8 days of recovery. A statistically significant difference was also found between animals exposed continuously for 4 h versus animals given two 2-h exposures separated by a 1-h break. Measures of f2-f1 and 3f1-2f2 indicated that they were more sensitive than 2f1-f2 to alterations in cochlear function after noise exposure.

    View details for Web of Science ID A1996UX13500001

    View details for PubMedID 8817301

  • EXTERNAL AND MIDDLE-EAR STATUS RELATED TO EVOKED OTOACOUSTIC EMISSION IN NEONATES ARCHIVES OF OTOLARYNGOLOGY-HEAD & NECK SURGERY Chang, K. W., Vohr, B. R., Norton, S. J., LEKAS, M. D. 1993; 119 (3): 276-282

    Abstract

    Screening auditory status prior to neonatal hospital discharge to identify newborns with severe hearing impairment is an important pediatric care priority. Evoked otoacoustic emission (OAE) testing is a quick noninvasive method. The purpose of this study was to determine the relationship between external auditory canal and middle ear status with click-evoked OAE. It was hypothesized that vernix caseosa, debris in the ear canal, and middle ear fluid contribute to the OAE fail rate.All neonates had an initial OAE examination. A second investigator, "blinded" to the results, examined all ears otoscopically, cleaned any obstructing debris, and repeated with a second OAE test.All neonates were tested in a designated nursery at a mean age of 43 +/- 21 hours.Forty-one full-term neonates were prospectively enrolled.The ear canals with debris were cleaned under direct vision with a pediatric swab dampened by an alcohol wipe.The primary outcome measure was the postcleaning OAE pass rate.The preotoscopic examination pass rate of 82 ears was 76%. The OAE pass rate improved to 91% after debris removal.The results indicate that the examination and cleaning of the external ear canal are important components of the neonatal screening process.

    View details for Web of Science ID A1993KQ55900003

    View details for PubMedID 8435165

  • Wegener's granulomatosis in an adolescent presenting with pachymeningitis, mastoid effusion and Horner's syndrome Int J Pediatr Otorhinolaryngol Extra Kohlberg, G. D., Truong, M. T., Chang, K. W. 2011; 6 (2): 80-84
  • Salivary Gland Anlage Tumor in a Neonate Presenting with Respiratory Distress: Radiographic and Pathologic Correlation AMERICAN JOURNAL OF NEURORADIOLOGY Mogensen, M. A., Lin, A. C., Chang, K. W., Berry, G. J., Barnes, P. D., Fischbein, N. J. 2009; 30 (5): 1022-1023

    Abstract

    We present a case of congenital salivary gland anlage tumor (SGAT) of the nasal septum in a 2-week-old infant who had difficulty breathing through her nose since birth. CT and MR imaging demonstrated a circumscribed mass within the nasal cavity that did not communicate with the intracranial compartment. Differential diagnosis and clinical significance of recognizing this rare lesion are reviewed.

    View details for DOI 10.3174/ajnr.A1364

    View details for Web of Science ID 000266133000027

    View details for PubMedID 19112069

  • Third branchial cleft fistula infected with Actinomyces Int J Pediatr Otorhinolaryngol Extra Chang, K. W., Lee, B. G., Gutierrez, K. M. 2008; 3 (1): 20-23
  • Familial laryngomalacia in two siblings with syndromic features INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY Chen, J. L., Messner, A. H., Chang, K. W. 2006; 70 (9): 1651-1655

    Abstract

    We present two siblings with severe laryngomalacia requiring surgical intervention during the newborn period, microcephaly, developmental delay, cleft palate, preaxial polydactyly, dysplastic nails and conductive hearing loss (persistent after tympanostomy tube placement). In addition the girl has microopthalmia and the boy was born with a patent ductus arteriosus, mild pelviectasis, and hypospadias. This combination of multiple congenital anomalies has not been described previously and may represent a previously undescribed syndrome with autosomal inheritance.

    View details for DOI 10.1016/j.ijporl.2006.04.010

    View details for Web of Science ID 000240528700022

    View details for PubMedID 16774790

  • Posttransplantation lymphoproliferative disorder of the paranasal sinuses in a child Int J Pediatr Otorhinolaryngol Extra Rosen, F. S., Bingham, D., Chang, K. W. 2006; 1 (1): 22-26
  • Evaluation and management of hoarseness in children. Current Opinion Oto Head Neck Surg Chang, K. W., Inglis, A. F. 1996; 4: 396-400
  • IATROGENIC HYPONATREMIA - A CAUSE OF DEATH FOLLOWING PEDIATRIC TONSILLECTOMY INTERNATIONAL JOURNAL OF PEDIATRIC OTORHINOLARYNGOLOGY MCRAE, R. G., WEISSBURG, A. J., Chang, K. W. 1994; 30 (3): 227-232

    Abstract

    Death following pediatric tonsillectomy is very rare. If deaths occur, they are most commonly due to bleeding or aspiration. In this presentation, we would like to illustrate another potentially lethal complication following the pediatric tonsillectomy, iatrogenic hyponatremia. We have encountered 3 patients who have developed post-operative hyponatremia. This has resulted in 2 deaths. The third patient was successfully treated and developed no permanent sequela. We will discuss the etiology and pathophysiology of post-operative hyponatremia including guidelines for administering fluid and electrolytes intra-operatively and post-operatively. We expect that fatal post-operative hyponatremia can be avoided in the pediatric tonsillectomy patients.

    View details for Web of Science ID A1994PR62600007

    View details for PubMedID 7836036

Stanford Medicine Resources: