Predictors of successful natural sleep MRI for sensorineural hearing loss in infants

OBJECTIVES

Cochlear implantation (CI) in children with sensorineural hearing loss (SNHL) before 12 months of age (mo) improves language outcomes. MRI is important to assess CI candidacy. Anesthesia before 3 years old may increase risk of neurocognitive delay. Natural sleep MRI (NS-MRI) is an emerging technique to avoid anesthesia in infants, but relies on successful sleep for adequate imaging. Our multidisciplinary team hypothesized the following predictors of successful NS-MRI for CI evaluation: age, distance travelled, comorbidities, primary language, insurance type, HL characteristics, time and duration of MRI.

METHODS

We performed retrospective review of children 0-12mo who attempted NS-MRI. The NS-MRI was successful if imaging was sufficient for definitive clinical management per the managing otolaryngologist.

RESULTS

Among 26 patients (29 scans), the median age was 3.2mo (range: 1.2-6.8mo), distance travelled was 16.3 miles (range: 0.9 to 365 miles), 12 (46%) children had medical comorbidities. 8 (31%) had public insurance. 10 (38%) had bilateral HL. 52% (15/29) of scans were successful. Patients with comorbidities had significantly lower odds of successful NS-MRI (OR 0.09; 95% CI 0.01-0.54). Success was not associated with age, distance travelled, insurance type, primary language, HL characteristics, time or duration of MRI on univariable analysis. All 11 children who failed NS-MRI underwent hearing-aid fitting and/or imaging with sedation and CI as clinically indicated before 12mo.

CONCLUSION

NS-MRI was successful in 52% of infants, regardless of age, demographics, HL or MRI characteristics. Unsuccessful NS-MRI did not result in delayed intervention. NS-MRI is an effective consideration for a broad range of infants with SNHL.

Racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing for sensorineural hearing loss

Understanding racial and ethnic disparities in diagnostic rates of genetic testing is critical for health equity. We sought to understand the extent and cause of racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing (CGT) for sensorineural hearing loss (SNHL). We performed a retrospective cohort study at two tertiary children’s hospitals on a diverse cohort of 240 consecutive pediatric patients (76% publicly insured, 82% non-White) with SNHL of unknown etiology who underwent CGT. Definite and possible genetic diagnoses were assigned for each patient, representing the likelihood of a genetic cause of hearing loss. Associations between diagnostic rates were examined. 3.8 ± 2.1 variants were detected per patient; this frequency did not vary between White/Asian and Hispanic/Black cohorts. Overall, 82% of variants were variants of uncertain significance (VUS). Compared with White and Asian subjects, variants identified among Hispanic and Black children were less likely to be classified as pathogenic/likely pathogenic (15% vs. 24%, p < 0.001), and Hispanic and Black children were less likely to have a definite genetic diagnosis (10% vs. 37%, p < 0.001). The adjusted odds ratio for definite genetic diagnosis in Black and Hispanic children compared with White and Asian children was 0.19. Expanding genetic diagnostic criteria to include predicted deleterious VUSs reduced these disparities between White/Asian and Hispanic/Black children, with comparable molecular diagnostic rates (41% vs. 38%, p = 0.72). However, in silico predictions are insufficiently valid for clinical use. Increased inclusion of underrepresented groups in genetic hearing-loss studies to clinically validate these variants is necessary to reduce racial and ethnic disparities in diagnostic efficacy of comprehensive genetic testing.

Efficacy of endoscopic sinus surgery alone versus in combination with neurosurgical intervention for the treatment of pediatric subdural empyema

OBJECTIVES

To compare treatment outcomes for sinogenic subdural empyema (SE) between those managed with initial endoscopic sinus surgery (ESS) alone versus those treated with a combination of ESS and craniotomy over the last decade at our institution. To better characterize subdural empyema with regard to presentation, causative pathogens, and treatment course.

METHODS

Retrospective single-center chart review to identify and evaluate pediatric SE patients between 2009 and 2019. Patients meeting inclusion criteria were classified in one of two groups: those who initially underwent ESS or frontal trephination without concurrent neurosurgical procedure and those who underwent craniotomy or burr hole in addition to a sinus procedure. Presenting characteristics and treatment outcomes were compared between the two groups.

RESULTS

Eighteen patients met inclusion criteria. The ESS alone and the ESS + craniotomy subgroups each had 9 patients with similar baseline characteristics. The ESS + craniotomy group was more likely to present with neurological symptoms (p = 0.039) and have multiple intracranial fluid collections (p = 0.046). 74.1% of patients presented to the Emergency Department (ED) or to their primary medical doctor and were treated with outpatient management prior to hospitalization with definitive surgical management. The most common presenting symptoms were fever, headache and nausea/vomiting. There were no differences between treatment groups in rate of return to the operating room (OR) (p = 1.00), length of stay (LOS) (p = 0.553), or adverse neurological outcomes (p = 0.456). 44.4% of patients in the ESS alone group eventually required neurosurgical intervention.

CONCLUSIONS

Surgical SE patients often present to medical professionals in the primary care setting or ED and are managed with outpatient treatment before admission with definitive treatment. In this small retrospective cohort patients who underwent sinus intervention alone had similar rates of return to OR, LOS and adverse neurological outcomes use as those who underwent a sinus procedure in coordination with a neurosurgical intervention. There may be a group of patients with SE who may be managed with endoscopic procedures alone and further studies should seek to determine the characteristics of this population.

Genetic Testing Leading to Early Identification of Childhood Ocular Manifestations of Usher Syndrome

OBJECTIVES

Hearing-loss gene panel testing (HLGPT) is increasingly accessible as a first-line test in determining the etiology of sensorineural hearing loss (SNHL) in children. A major advantage of HLGPT is early identification of syndromic forms of SNHL, especially Usher syndrome, prior to the development of overt syndromic phenotype, which may impact management and counseling. Here, we describe early ocular findings in children with clinically non-syndromic SNHL identified by HLGPT as having two variants associated with Usher Syndrome.

METHODS

A total of 184 children, ages 1 month - 15 years of age, evaluated at one tertiary pediatric children's hospital for clinically non-syndromic SNHL, underwent next-generation sequencing of 150 genes involved in hearing loss. Children with two variants in genes associated with Usher syndrome were referred for evaluation by pediatric ophthalmology.

RESULTS

A total of 18/184 tested children had two variants in Usher syndrome-associated genes, including MYO7A, GPR98 (ADGRV1), USH2A, and PDZD7. SNHL varied from moderate to profound. 29% of the children who underwent clinical ophthalmology evaluation were found to have previously unidentified retinal abnormalities on retinal imaging or electroretinography consistent with inherited retinal degeneration.

CONCLUSION

Among this ethnically and racially diverse pediatric population with apparently non-syndromic SNHL, HLGPT yielded a high proportion (10%) of children with two variants in genes associated with Usher syndrome. Early genetic testing allows early identification of variants conferring a diagnosis of Usher syndrome at a stage prior to visual symptoms. This allows for more informed genetic counseling, reproductive planning, and sensory deficit interventions.

LEVEL OF EVIDENCE

4 Laryngoscope, 131:E2053-E2059, 2021.

The Unified Airway: Does Asthma Influence Paranasal Sinus Pneumatization?

Asthma has been implicated as a driving force in lower airway remodeling; however, its effect on upper airway development has not been studied. Clinical disease, particularly cystic fibrosis (CF), has been associated with anatomical paranasal sinus variation, although the mechanism for these variations remains unclear. The purpose of this study was to determine whether asthma is associated with altered sinus pneumatization. Five hundred ninety-one computed tomography scans, including 303 adolescents (age 13-18) and 288 adults (age > 18), were evaluated using the Assessment of Pneumatization of the Paranasal Sinuses (APPS) instrument. The APPS score is validated for assessing anatomical variation and total sinus volume. A diagnosis of asthma was ascertained from the medical record, and patients with CF were included as a positive control group. Patients with asthma had mean APPS score of 9.66, compared to 9.85 for participants without asthma (P = .585). Subgroup analysis demonstrated similar findings among adults (P = .817) and adolescents (P = .585). Patients with a diagnosis of CF had significant sinus hypoplasia according to a mean APPS scores of 3.50 (P < .001). Sinus hypoplasia persisted in both adults (P < .001) and adolescents (P < .001) with CF. The presence of asthma is not associated with altered paranasal sinus pneumatization. In contrast, CF is associated with significantly reduced sinus pneumatization. These findings suggest that aberrant sinus pneumatization may not be a feature of asthma and that chronic mucosal respiratory disease is not a generalizable cause for altered paranasal sinus pneumatization.

Cochlear implant symmetry via template

Current trends in bilateral cochlear implantation (CI) favor a minimally invasive subperiosteal pocket technique. Symmetric receiver-stimulator (R/S) placement is an important goal for bilateral CI, especially with regard to patient satisfaction. In this article, we describe a method easily adopted to achieve optimal symmetry. Upon reviewing the Senior Author's 11 bilateral CI cases using the direct subperiosteal pocket technique with the proposed "mirror template," we found improved symmetry, which translated into high patient and family satisfaction regarding the aesthetics of the symmetric R/S placement.

Utility of polysomnography in determination of laryngomalacia severity

OBJECTIVE

To examine the efficacy of polysomnography in determining the severity of laryngomalacia in pediatric patients.

METHODS

Prospective cohort study. Pediatric patients referred to our pediatric otolaryngology department with a polysomnogram already performed for a presumptive diagnosis of laryngomalacia were enrolled in the study. Patients with concurrent airway lesions or neuromuscular disorders were excluded. Patients underwent history, physical exam, and flexible fiberoptic laryngoscopy. These results were used to calculate a total laryngomalacia severity score.

RESULTS

25 pediatric patients (n = 25) with an average age of 3.9 months at time of initial evaluation met criteria for enrollment in our study. 100% of patients had obstructive sleep apnea by definition. 80% of these patients underwent supraglottoplasty. The average AHI of those who underwent surgery (57.26) was not significantly different in those who underwent surgery vs. those that did not (55.43) (p = 0.41). In comparison, the average laryngomalacia severity score based from history, physical exam and flexible laryngoscopy was significantly greater in the patients that required supraglottoplasty (11.16) vs. those who did not (5.33) (p = 0.03). In addition a higher laryngomalacia severity score was not correlated with a higher AHI (p = 0.81, r = 0.08, CI: -0.5197 to 0.6235).

CONCLUSION

In our cohort, polysomnography was not useful in determining the severity of laryngomalacia, did not correlate with the clinical evaluation, and alone was not predictive of the patients that would require surgical intervention. History, physical exam, and endoscopic findings remain reliable predictors of disease severity and need for operative intervention.

Dietary transfer of fluoranthene from an estuarine oligochaete (Monopylephorus rubroniveus) to grass shrimp (Palaemonetes pugio): Influence of piperonyl butoxide

The objective of this study was to determine the potential for dietary transfer of sediment-associated fluoranthene from tubificid oligochaetes (Monopylephorus rubroniveus) to grass shrimp (Palaemonetes pugio). Grass shrimp, either in the presence or absence of sublethal waterborne concentrations of the metabolic inhibitor, piperonyl butoxide (PBO), were fed fluoranthene-dosed oligochaetes for 5-days. All grass shrimp bioaccumulated fluoranthene; however, bioaccumulation was 3X higher in the presence of PBO. Trophic transfer coefficients (TTCs) were 0.02 and 0.01 in the presence and absence of PBO, respectively. Following the 5-day accumulation period, shrimp in both treatments were allowed to depurate for 3 days. Depuration rates were significantly higher in PBO-exposed shrimp. These results demonstrated that sediment-associated fluoranthene can be transferred through the diet from oligochaetes to grass shrimp, and the presence of PBO enhanced fluoranthene bioaccumulation. However, the comparatively low TTCs suggest that biomagnification of fluoranthene in estuarine food webs is low.

Phototoxicity of anthracene and pyrene to glochidia of the freshwater mussel Utterbackia imbecillis

The acute toxicity of photoactivated anthracene and pyrene to the glochidial larvae of the paper pondshell (Utterbackia imbecillis) was characterized in the laboratory using two sets of experiments. Acute toxicity tests designed to determine the overall sensitivity of glochidia to anthracene and pyrene were conducted under simulated sunlight (ultraviolet [UV]-A = 70+/-0.5 microW/cm2 [mean +/- standard deviation]). The median lethal concentration (LC50) and median lethal dose (LD50) of anthracene at 24 h were 1.93 (95% CI, 0.87-3.02) microg/L and 1.94 (1.87-2.00) microg/g glochidia, respectively. The LC50 and LD50 for pyrene at 24 h were 2.63 (2.38-2.90) microg/L and 6.36 (5.82-6.94) microg/g glochidia, respectively. Acute toxicity tests designed to delineate the relationship between the rate of mortality and UV intensity were conducted under one of four different UV intensities (UV-A = 15, 31, 50, and 68 microW/cm2). Regression analyses revealed that time to death decreased as tissue residue concentrations and UV intensity increased for both compounds. Based on measured tissue residues, anthracene was 1.5-fold more potent than pyrene and 3-fold more potent than fluoranthene. The lower potency of fluoranthene is in agreement with previously developed structure-activity relationships; however, these relationships predict equal potency between anthracene and pyrene. These findings suggest that glochidia of freshwater mussels are sensitive to photoactivated anthracene and pyrene at environmentally relevant concentrations, that the time-dependent mortality of glochidia can be accurately predicted through evaluating the product of tissue residue and light intensity, and that species-dependent factors may alter the predicted relative potencies of anthracene and pyrene.

Characterization of the acute toxicity of photoactivated fluoranthene to glochidia of the freshwater mussel, Utterbackia imbecillis

The acute photoactivated toxicity of fluoranthene to the glochidial larvae of the paper pondshell, Utterbackia imbecillis, was characterized in the laboratory using three sets of experiments. Toxicokinetic studies revealed that glochidia rapidly bioaccumulated fluoranthene, reaching an apparent steady state in 4 h. Based on a two-compartment model, uptake (Ku) and depuration (Kd) rate constants were 1394 ml/g/h and 0.769/h, respectively. However, experimental data suggested the presence of a fast and slow depuration compartment with a Kd of 0.290 and 0.031/h, respectively. Replicate 24-h acute toxicity tests designed to determine the overall sensitivity of glochidia to photoactivated fluoranthene were conducted under simulated sunlight (ultraviolet [UV]-A = 69.0 +/- 1.0 microW/cm2) (mean +/- standard deviation [SD]). Mean median lethal concentrations (LC50) of fluoranthene at 8, 16, and 24 h were 5.59 +/- 0.59, 4.09 +/- 0.57, and 2.45 +/- 0.45 micrograms/L, respectively. Mean median lethal doses (LD50) at the same time periods were 14.76 +/- 2.17, 11.66 +/- 2.82, and 6.98 +/- 1.31 micrograms/g dry weight, respectively. Acute toxicity tests designed to elucidate the relationship between the rate of mortality and UV intensity were conducted under one of four different UV intensities (UV-A = 15, 31, 50, and 68 microW/cm2). Regression analysis revealed that the time-dependent mortality of glochidia was inversely related to the product of initial tissue residue of fluoranthene and UV intensity. These findings suggest that glochidia of freshwater mussels are among the most sensitive organisms tested to date to photoactivated fluoranthene and the time-dependent mortality of glochidia can accurately be predicted through evaluation of the product of fluoranthene tissue residue and the light intensity to which the glochidia is exposed.

Seasonal responses of the mixed-function oxygenase system in the American oyster, Crassostrea virginica (Gmelin 1791), to urban-derived polycyclic aromatic hydrocarbons

Mixed-function oxygenase (MFO) system components (cytochrome P450 and b5, "423 peak" and NADPH cytochrome c reductase) and body burdens of polycyclic aromatic hydrocarbons (PAHs) were determined seasonally in oysters, Crassostrea virginica (Gmelin 1791), collected from an undeveloped estuary (North Inlet, SC) and an urbanized estuary (Murrells Inlet, SC). All MFO system components monitored in oysters from North Inlet demonstrated seasonal variations; levels were lowest during October 1992. Whole oyster PAH tissue levels were always higher in Murrells Inlet oysters compared with North Inlet oysters. Seasonal variation of PAH body burdens was evident in oysters from Murrells Inlet; the highest levels occurred during April 1993. Differences between the two estuaries were seasonally evident in most oyster MFO system components. Reductase activity was highest at the most contaminated Murrells Inlet site during October 1992 and April 1993. This seasonal variation was positively correlated to that of their PAH body burdens. Cytochrome P450 content was also elevated at the most contaminated site during April 1993. These results suggest that reductase activity and cytochrome P450 content in Murrells Inlet oysters were induced by the high PAH body burdens during April 1993 and indicate their potential as molecular biomarkers of PAH contamination.