Evan J. Propst

Inner Ear Dysplasia is Common in Children With Down Syndrome (trisomy 21)

Objectives/Hypothesis: Middle and external ear anomalies are well recognized in Down syndrome (DS, trisomy 21). Inner ear anomalies are much less frequently described. This study reviews inner ear morphology on imaging to determine the prevalence of cochlear and vestibular anomalies in children with DS.

Neuroanatomic Differences in Children With Unilateral Sensorineural Hearing Loss Detected Using Functional Magnetic Resonance Imaging

OBJECTIVE Functional magnetic resonance imaging (fMRI) provides information about neuronal excitation by measuring changes in cerebral hemodynamics. This study used fMRI to compare neuroanatomic activation patterns in children with unilateral sensorineural hearing loss (USNHL) with the neuroanatomic activation patterns in normally hearing individuals. DESIGN Patients were presented with narrowband noise and speech-in-noise tasks while undergoing fMRI of the brain. In the narrowband noise task, 5 chirps at center frequencies of 250 Hz, 500 Hz, 1 kHz, 2 kHz, and 4 kHz were presented monaurally for 1 second in a randomized order to children in both groups. In the speech-in-noise task, Bamford-Kowal-Bench (BKB) sentences were presented over 4-talker babble to both ears, and scans were acquired after each stimulus. We compared fMRI data across groups using independent component analysis and Bayesian (hierarchical) linear models. SETTING Tertiary referral center. PATIENTS Twelve children with USNHL and 23 normally hearing controls. INTERVENTIONS Perform fMRI while subject listens to narrowband and speech-in-noise tasks. MAIN OUTCOME MEASURES Neuroanatomic differences in fMRI. RESULTS In the narrowband noise task, children with USNHL had less activation of auditory areas and failed to activate auditory association areas and attention networks compared with normally hearing controls. In the speech-in-noise task, children with USNHL activated only secondary auditory processing areas in the left hemisphere, while controls activated these areas bilaterally. Children with right-sided USNHL failed to activate attention areas that were activated in controls and in children with left-sided USNHL. Only children with left-sided USNHL activated bilateral visual association areas. CONCLUSIONS Results show significant differences in the cortical processing of sound between children with severe to profound USNHL and normally hearing children. These differences may account for the functional auditory problems that children with USNHL experience.

Dose-dependent suppression of the electrically elicited stapedius reflex by general anesthetics in children undergoing cochlear implant surgery.

BACKGROUND: Cochlear implants stimulate the auditory nerve to enable hearing. Determining appropriate upper and lower limits of stimulation is essential for successful cochlear implantation. The intraoperative evoked stapedius reflex threshold (ESRT) and evoked compound action potential (ECAP) are commonly used to determine the limits of implant stimulation. In this study, we evaluated the dose-related effects of sevoflurane, desflurane, isoflurane, and propofol on the intraoperative ESRT and ECAP. METHODS: Forty-four children aged 6 mo to 17 yr undergoing cochlear implantation were recruited. Each child was randomly assigned to receive sevoflurane, desflurane, isoflurane, or propofol. Evoked responses were measured by a blinded investigator at end-tidal anesthetic concentrations corresponding to 0, 0.75, and 1.5 age-adjusted minimum alveolar concentration administered in random sequence and at targeted blood concentrations of propofol of 0, 1.5, and 3.0 &mgr;g/mL. Data were analyzed using one-way repeated-measures analysis of variance. P < 0.05 was considered statistically significant. RESULTS: The ESRT increased dose dependently with increasing volatile anesthetic concentration (P < 0.01). The stapedius reflex was completely abolished by volatile anesthesia in more than half of children. Propofol minimally affected the ESRT. In contrast, the ECAP was unaffected by anesthesia. CONCLUSIONS: Volatile anesthetics suppress the stapedius reflex in a dose-dependent manner, suggesting that ESRT measurements acquired during volatile anesthesia will overestimate the maximum comfort level, which may cause discomfort postoperatively and adversely affect the child’s adaptation to the implant. We advise against the use of volatile anesthetics for measurement of the stapedius reflex threshold during cochlear implant surgery.

Oropharyngeal Stenosis: A Complication of Multilevel, Single-Stage Upper Airway Surgery in Children

OBJECTIVES To describe oropharyngeal stenosis (OPS), a potential complication of multilevel, single-stage upper airway surgery involving lingual tonsillectomy in children, and to discuss the manner in which OPS may be managed successfully. DESIGN Case series with an average follow-up of 12 months. SETTING Tertiary care childrens hospital. PATIENTS Medical charts were reviewed for 104 patients who underwent lingual tonsillectomy over a 30-month period from January 1, 2007, to June 30, 2009. INTERVENTION Multilevel, single-stage upper airway surgery, including lingual tonsillectomy. MAIN OUTCOME MEASURE Development of OPS noted during office or intraoperative examination. RESULTS Forty-nine of 104 patients underwent multilevel, single-stage upper airway procedures that included lingual tonsillectomy. Four of these 49 patients developed OPS, for a complication rate of 8.2%. Three patients required pharyngoplasty (scar release, debulking of fibrotic tissue, and reorientation of the scar) and triamcinolone injections in the operating room. A fourth patient underwent simple scar release in the operating room. No patient who underwent lingual tonsillectomy alone or in combination with an additional procedure at the same level of the upper airway developed OPS. CONCLUSIONS Oropharyngeal stenosis is a potential complication of multilevel, single-stage upper airway surgery involving lingual tonsillectomy in children. Although there is pressure to perform multilevel procedures that address each site of upper airway obstruction in 1 sitting, this case series suggests the need for a more conservative, staged approach if lingual tonsillectomy is planned.

Successful cochlear implantation in a child with Keratosis, Icthiosis and Deafness (KID) Syndrome and Dandy-Walker malformation

Keratosis, Icthiosis, and Deafness (KID) Syndrome is a rare congenital disorder associated with dominant connexin 26 mutations, affecting epidermis, corneal epithelium, and inner ear. Given eventual visual impairment, cochlear implantation is an important consideration despite an increased risk of wound complications. We present a child with KID Syndrome and bilateral profound sensorineural hearing loss associated with a novel heterozygous missense D50A connexin 26 mutation (c.149A > C). Imaging revealed mild cochlear malformation and Dandy-Walker malformation. She received a cochlear implant at the age of 12 months, using a small incision approach. Following an immediate minor wound infection, implantation has been successful without further complication over 4 years.

Ultrasound to differentiate thyroglossal duct cysts and dermoid cysts in children

To determine if ultrasound could differentiate between thyroglossal duct cysts (TGDC) and midline dermoid cysts (DC).

Pediatric Tracheal Reconstruction Using Cadaveric Homograft

OBJECTIVE To examine the indications, risks, and surgical outcomes after tracheal reconstruction using cadaveric homograft in children. DESIGN Retrospective medical record review. SETTING Tertiary referral center. PATIENTS Ten children (4 boys and 6 girls). INTERVENTION Tracheal reconstruction using cadaveric homograft. MAIN OUTCOME MEASURES Cause of stenosis, number and type of procedures before homograft reconstruction, severity of preoperative stenosis, surgical approach, homograft length, duration of stenting, number and type of procedures after reconstruction, and rates of decannulation and survival. RESULTS Ten children (mean [SD] age, 8.4 [5.5] years) underwent 14 tracheal reconstructions using cadaveric homograft. Patients had an average of 7.0 (range, 1-16) procedures before homograft reconstruction, including an average of 2.8 (range, 0-6) major open airway reconstructions. Mean (SD) pretracheoplasty Myer-Cotton grade of stenosis was 3.80 (0.42) (range, 3-4), and all patients were tracheotomy dependent. A cervical approach was used in 12 reconstructions (86%), and 2 (14%) required median sternotomy. Mean (SD) homograft length was 3.9 (1.7) cm (range, 2-8 cm), which was approximately 0.60 times the length of the total recipient trachea. Mean (SD) duration of stenting for all homografts was 0.67 (0.46) years (range, 0.24-1.98 years). The survival rate was 90% after a mean follow-up of 5.47 (1.52) years (range, 3.32-7.55 years). Surviving patients required an average of 7.38 (5.52) procedures (range, 1-19) after homograft transplant, including an average of 1 major open airway reconstruction (range, 0-4). The mean (SD) grade of stenosis after the final homograft placement was 1.89 (1.27) (range, 1-4). Although the operation-specific decannulation rate was only 7% (1 of 14), the overall decannulation rate eventually reached 60%. Statistical bootstrapping methods and a multivariate regression model determined that increasing patient age (odds ratio, 1.21; 95% confidence interval, 1.07-1.36), increasing number of prior procedures (1.26; 1.02-1.57), and increasing homograft length (2.42; 1.60-3.40 [P < .001]) were associated with an increased risk of no decannulation after tracheal homograft reconstruction. CONCLUSIONS Tracheal reconstruction using cadaveric homograft is an option in children who have undergone multiple airway surgical procedures and present with long-segment stenoses that cannot be bridged using conventional methods. These patients must receive close postoperative follow-up. Subsequent procedures are almost always required before decannulation, and eventual decannulation rates are only 60%. Decannulation rates are lower in older patients who have previously undergone many procedures and require a long tracheal homograft.

Midline posterior glossectomy and lingual tonsillectomy in obese and nonobese children with down syndrome: Biomarkers for success

To examine outcomes following midline posterior glossectomy (MPG) plus lingual tonsillectomy (LT) for the treatment of significant obstructive sleep apnea (OSA) in children with Down syndrome (DS).

A recurrent EYA1 mutation causing alternative RNA splicing in branchio‐oto‐renal syndrome: Implications for molecular diagnostics and disease mechanism

Branchio‐oto‐renal syndrome is a heterogeneous disorder inherited in an autosomal dominant pattern, characterized by branchial arch abnormalities, hearing loss and renal abnormalities, with mutations in EYA1 reported in 30–70% of patients. We have applied a molecular testing strategy of sequencing of the complete coding region/flanking intronic regions and multiple ligation probe amplification analysis of EYA1 to a pediatric branchio‐oto‐renal proband cohort. EYA1 mutations were identified in 82% (14/17) of the probands. We also describe a novel recurrent EYA1 mutation c.867 + 5G > A found in five unrelated affected patients. RNA analysis showed that c.867 + 5G > A affects EYA1 splicing, producing an aberrant mRNA transcript lacking exon 8 and resulting in premature termination in exon 9. The aberrant transcript was present at approximately 50% level of wild‐type EYA1 mRNA in fibroblasts, and is predicted to encode an EYA1 protein retaining the amino terminal transcriptional coactivator region but lacking the conserved carboxy terminal Eya phosphatase domain. Patients with the c.867 + 5G > A mutation were found to have more severe renal abnormalities than probands with other mutations in this cohort. Analysis of the c.867 + 5G > A mutation suggests that certain transcripts of EYA1 escape nonsense‐mediated decay and encode truncated EYA proteins that may be capable of dominant‐negative interactions producing distinct phenotypic features within the branchio‐oto‐renal spectrum.

NUT midline carcinoma of the larynx: an international series and review of the literature†

NUT midline carcinoma (NMC) is a rare undifferentiated and aggressive carcinoma that locates characteristically to the midline of the head and neck, and mediastinum. NMC is characterized by chromosomal rearrangements of the gene NUT, at 15q14. The BRD4 gene on 19q13 is the most common translocation partner forming a fusion oncogene, BRD4–NUT. By the end of 2014, the International NUT Midline Carcinoma Registry had 48 patients treated for NMC. Laryngeal NMC are exceedingly rare, and we report a case series of seven cases.