Literature Review: A Roundup of Important Recent Studies

Bottom line: The UCSF otolaryngology hospitalist model has encouraged better communication and collaboration with other services and allows the hospitalist to provide educational opportunities to clinical residents.

Citation: Russell MS, Eisele D, Murr A. The otolaryngology hospitalist: a novel practice paradigm. Laryngoscope. 2013;123:1394-1398.

—Reviewed by Amy Eckner

Enlarged Vestibular Aqueduct Indicates Stronger Risk of Hearing Loss Progression

Is an enlarged vestibular aqueduct (EVA) an indicator of increased hearing loss progression risk?

Background: Temporal bone abnormalities like EVA are recognized as an important factor of sensorineural hearing loss. The otologic phenotype is variable for EVA and can be associated with fluctuating and progressive hearing loss. Although unilateral hearing loss (UHL) in EVA patients has been reported, it is not well described. EVA has also been associated with disorders such as Pendred syndrome, CHARGE syndrome, Waardenburg syndrome and branchio-oto-renal syndrome.

Study design: Retrospective cohort study of all children seen at their center and diagnosed with EVA or unilateral hearing loss without EVA from 1998 to 2010 at one care facility, with a pure tone average (PTA) for each ear, CT scans for temporal bone structure and genomic testing.

Setting: Ear and Hearing Center, Division of Pediatric Otolaryngology, Cincinnati Children’s Hospital Medical Center.

Synopsis: There were 144 patients who met the inclusion criteria. Unilateral EVA was identified in 74 (42 left side, 32 right side); the median age for hearing loss was 59.5 months, and the median follow-up time was 37.8 months. Forty-five patients with EVA had UHL. There was no statistical difference in hearing or the median PTA between unilateral and bilateral EVA patients with hearing loss. There was no significant difference in temporal bone measurements in patients with unilateral EVA and ipsilateral hearing loss, and in all ears with EVA and normal hearing. The proportion of ears with progressive hearing loss was slightly higher for bilateral EVA patients than for unilateral EVA patients. The median change in PTA for all ears was 5.0 dB. Progression rate was significantly correlated with the midpoint but not the operculum in bone measurement. Significantly more patients with bilateral than with unilateral EVA tested positive for Pendred syndrome gene mutation. Patients with UHL and EVA were more likely to suffer contralateral hearing loss than those without EVA. Hearing loss at 250 Hz in EVA patients is strongly correlated with PTA severity and UHL progression. Limitations included possible biases in how data were entered and difficulty assessing the true prevalence of pediatric unilateral EVA.