Mark J. Halsted

Enlarged vestibular aqueduct syndrome in the pediatric population.

Objective To correlate clinical and audiometric findings with the radiologic appearance in patients with enlarged vestibular aqueduct. Design A retrospective review of data from enlarged vestibular aqueduct patients identified in a pediatric hearing-impaired database of 1,200 patients. Setting A tertiary care pediatric referral center. Patients Subjects were included for study with a radiographic diagnosis of enlarged vestibular aqueducts in at least one ear by a pediatric neuroradiologist. Main Outcome Measures Audiometric evaluations and radiographic temporal bone measurements. Results Seventy-seven patients were identified with an enlarged vestibular aqueduct with a male-to-female ratio of 1:1.5. Patients were followed for a mean of 34 months (range, 0–179 months). Hearing loss was bilateral in 87% of cases. Vestibular symptoms were present in only three (4%) of the patients. Three patients (4%) suffered a sudden decrease in hearing after mild head trauma. Borderline enlargement of the vestibular aqueduct was associated with varying degrees of sensorineural hearing loss. Ninety-seven percent (64 of 66) of ears in control subjects with no sensorineural hearing loss had normal vestibular aqueduct measurements at the midpoint and operculum. Overall, the audiogram remained stable in 51% of ears, fluctuated in 28%, and progressively worsened in 21%. Measurements of the vestibular aqueduct at the midpoint and the operculum did not correlate with the audiometric threshold or the audiogram configuration. However, mean vestibular aqueduct size at the operculum was significantly larger in those with a progressive loss when compared with those with a fluctuating or stable hearing outcome. Conclusions Overall, audiometric thresholds remained generally stable, with sudden deterioration of hearing after head trauma seen in only three male patients. Progression of hearing loss after head trauma was not a significant finding in our patient population. Vestibular aqueduct opercular size alone showed a direct correlation with the audiometric outcome. Borderline enlarged vestibular aqueduct measurements appear to be associated with sensorineural hearing loss.

The large vestibular aqueduct: A new definition based on audiologic and computed tomography correlation:

Objective The study goal was to determine the prevalence and clinical significance of a large vestibular aqueduct (LVA) in children with sensorineural hearing loss (SNHL). Study Design and Setting We conducted a retrospective review of a pediatric SNHL database. One hundred seven children with SNHL were selected and their radiographic and audiometric studies were evaluated. Radiographic comparisons were made to a group of children without SNHL. Results A vestibular aqueduct (VA) larger than the 95th percentile of controls was present in 32% of children with SNHL. Progressive SNHL was more likely to occur in ears with an LVA and the rate of progressive hearing loss was greater than in ears without an LVA. The risk of progressive SNHL increased with increasing VA size as determined by logistic regression analysis. Conclusions An LVA is defined as one that is ≥2mm at the operculum and/or ≥1 mm at the midpoint in children with nonsyndromic SNHL. An LVA appears to be more common than previously reported in children with SNHL. A linear relationship is observed between VA width and progressive SNHL. Significance The finding of an LVA in children with SNHL provides diagnostic as well as prognostic information.

Design, Implementation, and Assessment of a Radiology Workflow Management System

OBJECTIVE The objective of this article is to describe the development, launch, and outcomes studies of a paperless workflow management system (WMS) that improves radiology workflow in a filmless and speech-recognition environment. MATERIALS AND METHODS The WMS prioritizes cases automatically on the basis of medical and operational acuity factors, automatically facilitates communication of critical radiology results, and provides permanent documentation of these results and communications. It runs in parallel with an integrated radiology information system (RIS)-PACS and speech-recognition system. Its effects on operations, staff stress and satisfaction, and patient satisfaction were studied. RESULTS Despite an increase in caseload volume after the launch of the WMS, case turnaround times, defined as the time between case availability on PACS and signing of the final radiology staff interpretation, decreased for all case types. Median case turnaround time decreased by 33 minutes (22%) for emergency department, 47 minutes (37%) for inpatient, and 22 minutes (38%) for outpatient radiology cases. All reductions were significant at a p value of < 0.05. Interruptions were reduced, consuming an estimated 28% less radiology staff time, after implementation. Patient perceptions of radiology service timeliness showed modest improvement after the WMS was implemented. Staff satisfaction showed no significant change. CONCLUSION There is room for improvement in radiology workflow even in departments with integrated RIS-PACS and speech-recognition systems. This study has shown that software tools that coordinate decentralized workflow and dynamically balance workloads can increase the efficiency and efficacy of radiologists. Operational benefits, such as reduced reading times, improvements in the timeliness of care (both actual and as perceived by patients), and reduced interruptions to radiologists, further reinforce the benefits of such a system. Secondary benefits, such as documenting communication about a case and facilitating review of results, can also promote more timely and effective care. Although use of the system did not result in a substantial improvement in staff perceptions, neither did it reduce their satisfaction, suggesting that these operational improvements were not achieved as a trade-off against the quality of the work environment.

When Is the Vestibular Aqueduct Enlarged? A Statistical Analysis of the Normative Distribution of Vestibular Aqueduct Size

BACKGROUND AND PURPOSE: The size of vestibular aqueducts (VAs) seen on CT studies varies. The current practice of calling a VA enlarged when it exceeds a certain threshold (eg, 1.5 mm at the midpoint) is arbitrary. Our hypothesis was that statistical analysis of the range of VA widths in a normal-hearing population would lead to a mathematic definition of the upper-limit-of-normal VA width. Materials and METHODS: The VA midpoint and opercular widths were measured in 73 children with normal hearing. Statistical analysis yielded values of the 99th, 97.5th, 95th, 90th, 75th, and 50th percentiles for this normal distribution. RESULTS: The upper-limit-of-normal (95th percentile) values for the VA midpoint and opercular widths were 0.9 and 1.9 mm, respectively. The VAs with greater widths may reasonably be considered enlarged. CONCLUSION: The VAs with midpoint or opercular widths of 1.0 and 2.0 mm or greater, respectively, are enlarged.

Temporal bone abnormalities associated with hearing loss in Waardenburg syndrome.

Objectives/Hypothesis: The objectives were to correlate audiometric thresholds with radiological findings and to determine the prevalence of inner ear radiological abnormalities in patients with hearing loss and Waardenburg syndrome. Study Design: The study was a retrospective review of patients with Waardenburg syndrome identified in a pediatric hearing‐impaired population and human genetics clinic. Methods: Nine children with Waardenburg syndrome were identified. Eighty‐nine children without sensorineural hearing loss served as control subjects. Clinical data, audiometric thresholds, and radiographic temporal bone measurements in these children were analyzed. Results: Seven children were identified with hearing loss and Waardenburg syndrome. Four children had Waardenburg syndrome type 1, and three children had Waardenburg syndrome type 2. The overall prevalence of hearing loss in the total study population with Waardenburg syndrome was 78%. The mean pure‐tone average was 99 dB. All of the children had sensorineural hearing loss. The hearing outcome was stable in 86% of the children. Twelve temporal bones were available for radiological analysis by computed tomography. Enlargement of the vestibular aqueduct was found in 50% of the CT scans. There was a significant difference in measurements of vestibular aqueduct width at the midpoint between the patients with Waardenburg syndrome and the control group (P < .05). There were also significant differences in the measurements of the vestibule (P = .0484), internal auditory canal (P = .0092), and modiolus (P = .0045) between the children with Waardenburg syndrome and the control group. Conclusion: A profound sensorineural hearing loss was characteristic of the study population with Waardenburg syndrome. Overall, 100% of patients with hearing loss and Waardenburg syndrome had temporal bone anomalies on at least one measurement of their inner ear, and 50% had an enlargement of the vestibular aqueduct at the midpoint. As shown by computed tomography, enlargement of the vestibular aqueduct and the upper vestibule, narrowing of the internal auditory canal porus, and hypoplasia of the modiolus are features of Waardenburg syndrome.

Diagnostic errors by radiology residents in interpreting pediatric radiographs in an emergency setting

BackgroundThere are few data regarding the frequency and type of diagnostic errors made by radiology residents and fellows (“trainees”). However, increasing interest in reducing medical errors highlights the need to analyze which areas of medical knowledge are most problematic for physicians-in-training, including radiology trainees. Once these areas are identified, they can be emphasized during training.ObjectiveTo quantify the diagnostic errors made by radiology trainees interpreting radiographs from a pediatric emergency department.Materials and methodsA total of 23,273 dictations of emergency radiographs performed over a 1-year period at a pediatric hospital were analyzed for corrections after staff interpretation and for type and incidence of missed abnormalities by radiology trainees. Errors were categorized by type of pathology and anatomic region.ResultsOf the 80 errors detected, 90% were false negatives and 69% were recurrent. Most errors (69%) involved the diagnosis of fractures and/or dislocations. Sixty-one percent of all recurrent errors involved buckle, Salter II, avulsion, and transverse fractures—yet these cases constituted only 3% of all cases seen during the study period.ConclusionThe most common errors made by radiology trainees can be identified. By targeting these errors, training programs can improve the quality and relevance of the education they provide.

Audiologic and temporal bone imaging findings in patients with sensorineural hearing loss and GJB2 mutations

Our objectives were to determine genotype‐phenotype correlations in patients with sensorineural hearing loss (SNHL) who undergo testing for GJB2 mutations and to examine the relationship of temporal bone anomalies seen on computed tomography (CT) and GJB2 mutations.