Imaging innovations in temporal bone disorders

Usage Patterns of CT and MRI in the Evaluation of Otologic Disease

OBJECTIVE

To evaluate the current trends and usage patterns of radiographic imaging for otologic disease by specialty, length of practice, practice setting, geographic region, and pediatric volume.

STUDY DESIGN

Cross-sectional study.

SETTING

Survey of physicians.

SUBJECTS

General Otolaryngologists and Otologists/Neurotologists (O/N) of the American Academy of Otolaryngology - Head and Neck Surgery (AAO-HNS).

METHODS AND OUTCOME MEASURES

An electronic questionnaire was distributed to AAO-HNS members. Respondents were separated into groups by specialty, length of practice, practice setting, region, and pediatric exposure. Chi-square tests were performed for the determination of significance.

RESULTS

The survey was sent to 5,168 members of AAO-HNS. The response rate was 10.6% (n = 546) and 18.1% for only O/N (n = 143). Most respondents were generalists (74%), in practice >20 years (51%), with a primarily adult practice (95%). O/N were more often academics (44 versus 17% combined, 40% private; p < 0.001) and saw fewer children (80 fewer than 25%; p < 0.001). Compared with generalists, O/N were more likely to respond with more frequent and earlier magnetic resonance imaging (MRI) utilization in the workup of the majority of otologic diseases. Significant differences in usage patterns for various conditions were demonstrated across all categories, but specialty training was the most common. Generalists (34 versus 12% of O/N; p < 0.001), physicians practicing >20 years (32 versus 18% of < 5 yrs; p = 0.006), and private practice physicians (34 versus 14-20% of others; p < 0.001) relied more heavily on the radiology report to interpret MRI scans.

CONCLUSION

Subspecialty training seems to be the main variable correlating with significant differences in the use of MRI and computed tomography imaging in patients with otologic disease.

Advanced Magnetic Resonance Imaging of the Skull Base

Magnetic resonance (MR) imaging is a crucial tool for evaluation of the skull base, enabling characterization of complex anatomy by utilizing multiple image contrasts. Recent technical MR advances have greatly enhanced radiologists' capability to diagnose skull base pathology and help direct management. In this paper, we will summarize cutting-edge clinical and emerging research MR techniques for the skull base, including high-resolution, phase-contrast, diffusion, perfusion, vascular, zero echo-time, elastography, spectroscopy, chemical exchange saturation transfer, PET/MR, ultra-high-field, and 3D visualization. For each imaging technique, we provide a high-level summary of underlying technical principles accompanied by relevant literature review and clinical imaging examples.

The diagnostic value of computed tomography in delayed complications after cochlear implantation

BACKGROUND

Delayed complications after cochlear implant (CI) surgery can result in the need for revision surgery. Temporal bone computed tomography (tCT) is frequently used in the diagnostic work-up for these patients.

AIMS/OBJECTIVES

We aimed to test for the value of tCT in delayed complications after CI surgery.

MATERIAL AND METHODS

Retrospective chart review including all patients with CI who were consecutively enrolled in our academic tertiary care centre and received a tCT due to delayed complications between January 2008 and December 2017.

RESULTS

A total of 85 patients with a mean age of 28 years at CI surgery were identified. Mean time between CI and tCT was 4.3 years. Reasons for performance of tCT were device malfunction (20%), cephalgia (20%), scalp hematoma/seroma (15.3%), device failure (11.8%), vertigo (10.6%), local infection (7.1%), trauma (5.9%), meningism (3.5%), tinnitus (3.5%) and facial palsy (2.4%). No abnormalities in tCT were detected in 82.4%. However, an abnormal tCT was a predictor for surgical therapy (p < .001).

CONCLUSIONS AND SIGNIFICANCE

We recommend the performance of tCT in CI patients with delayed complications to identify or rule out pathology in order to choose the most ideal and relevant individual treatment.

Head and neck paragangliomas: A two-decade institutional experience and algorithm for management

Objectives

Paragangliomas of the head and neck and cranial base are typically benign, slow‐growing tumors arising within the jugular foramen, middle ear, carotid bifurcation, or vagus nerve proper. The objective of this study was to provide a comprehensive characterization of our institutional experience with clinical management of these tumors and posit an algorithm for diagnostic evaluation and treatment.

Methods

This was a retrospective cohort study of patients undergoing treatment for paragangliomas of the head and neck and cranial base at our institution from 2000–2017. Data on tumor location, catecholamine levels, and specific imaging modalities employed in diagnostic work‐up, pre‐treatment cranial nerve palsy, treatment modality, utilization of preoperative angiographic embolization, complications of treatment, tumor control and recurrence, and hereditary status (ie, succinate dehydrogenase mutations) were collected and summarized.

Results

The mean (SD) age of our cohort was 51.8 (±16.1) years with 123 (63.4%) female patients and 71 (36.6%) male patients. Catecholamine‐secreting lesions were found in nine (4.6%) patients. Fifty‐one patients underwent genetic testing, with mutations identified in 43 (20 SDHD, 13 SDHB, 7 SDHD, 1 SDHA, SDHAF2, and NF1). Observation with serial imaging, surgical extirpation, radiation, and stereotactic radiosurgery were variably employed as treatment approaches across anatomic subsites.

Conclusion

An algorithmic approach to clinical management of these tumors, derived from our longitudinal institutional experience and current empiric evidence, may assist otolaryngologists, radiation oncologists, and geneticists in the care of these complex neoplasms.

Level of Evidence

4

Paragangliomas of the Head and Neck

Paragangliomas of the head and neck are rare vascular skull-base tumors derived from the paraganglionic system with an estimated incidence of 1:30,000 accounting for 3% of all paragangliomas. The most common paraganglioma locations of the head and neck in descending order are the carotid body, jugular, tympanic, and vagal paragangliomas. This article discusses the clinical characterics, normal anatamy, imaging findings and protocols, pathology, staging, and differential diagnosis for paragangliomas of the head and neck.