Faculty Bibliography

OBJECTIVE:Imaging is crucial in the assessment of head and neck cancers for site, extension, and enlarged lymph nodes. Restriction spectrum imaging (RSI) is a new diffusion-weighted magnetic resonance imaging (MRI) technique that enhances the ability to differentiate aggressive cancer from low-grade or benign tumors and helps guide treatment and biopsy. Its contribution to imaging of brain and prostate tumors has been previously published. However, there are no prior studies using RSI sequence in head and neck tumors. The purpose of this study was to evaluate the feasibility of performing RSI in head and neck cancer. METHODS:An additional RSI sequence was added in the routine MRI neck protocol for 13 patients diagnosed with head and neck cancer between November 2018 and April 2019. Restriction spectrum imaging sequence was performed with b values of 0, 500, 1500, and 3000 s/mm 2 and 29 directions on 1.5T magnetic resonance scanners.Diffusion-weighted imaging (DWI) images and RSI images were compared according to their ability to detect the primary malignancy and possible metastatic lymph nodes. RESULTS:In 71% of the patients, RSI outperformed DWI in detecting the primary malignancy and possible metastatic lymph nodes, whereas in the remaining cases, the 2 were comparable. In 66% of the patients, RSI detected malignant lymph nodes that DWI/apparent diffusion coefficient failed to detect. CONCLUSIONS:This is the first study of RSI in head and neck imaging and showed its superiority over the conventional DWI sequence. Because of its ability to differentiate benign and malignant lymph nodes in some cases, the addition of RSI to routine head and neck MRI should be considered.

OBJECTIVE:To determine if metal reduction magnetic resonance imaging sequences and changes in implant placement minimize artifact from cochlear implants and improve visualization of intracranial structures. STUDY DESIGN/METHODS:Cadaveric study. SETTING/METHODS:Tertiary referral center. PATIENTS/METHODS:Five cadaveric heads. INTERVENTIONS/METHODS:Specimens were implanted with Advanced Bionics HiRes Ultra3D devices at nasion-external auditory canal angles of 90, 120, and 160 degrees, and distances from the external auditory canal of 9 or 12 cm. Standard brain/internal auditory canal (IAC) sequences with metal artifact reducing technique were acquired in a 1.5T scanner. MAIN OUTCOME MEASURES/METHODS:The primary outcome was visibility of 14 intracranial structures graded on a 4-point scale (1, structures <50% visible; 2, >50% visible with some areas nonvisible from artifact; 3, artifact present but adequate for diagnosis; and 4, high quality). Scores were determined by experienced head and neck radiologists and compared with one-way analysis of variance. RESULTS:Imaging sequences included axial 5-mm whole-brain turbo spin echo (TSE) T2 with right to left and anterior to posterior encoding, fluid-attenuation inversion recovery high bandwidth, axial 5-mm whole-brain slice-encoding metal artifact correction (SEMAC), axial IAC constructive interference in steady state, and axial 3-mm T1 IAC with and without fat saturation. T1 IACs in axial and coronal planes were best for ipsilateral structures overall (mean [standard deviation {SD}], 3.8 [0.6] and 3.8 [0.5]). SEMAC (mean [SD], 3.5 [0.8]) was superior to TSE with anterior to posterior encoding (mean [SD], 3.5 [0.9) for ipsilateral cortex, cerebellopontine angle, and brainstem/cerebellum, and equivalent for the inner ear. Constructive interference in steady state and T1 with fat saturation were poor for all ipsilateral structures (mean, 2.8 [ p < 0.01]; mean, 3.1 [ p < 0.01]). The 120 degrees/12 cm position was overall best, although the 120 degrees/9 cm position still afforded visualization of ipsilateral structures; other angles and distances conferred slight advantages for specific structures of interest. CONCLUSIONS:SEMAC and T2 TSE with anterior to posterior encoding sequences provide artifact suppression while retaining excellent image quality. Different placement angles did not confer improvement in visualization, although placement distances provided slight advantages for some structures.

BACKGROUND AND PURPOSE/OBJECTIVE:-branchio-oto-renal syndrome and healthy controls. MATERIALS AND METHODS/METHODS:Temporal bone CT or MR imaging from 40 individuals with branchio-oto-renal syndrome and 40 controls was retrospectively reviewed. Cochlear offset was determined visually by 2 independent blinded readers and then quantitatively via a standardized technique yielding the cochlear turn alignment ratio. The turn alignment ratio values were compared between cochleae qualitatively assessed as "not offset" and "offset." Receiver operating characteristic analysis was used to determine the ability of the turn alignment ratio to differentiate between these populations and an optimal cutoff turn alignment ratio value. Cochlear offset and turn alignment ratio values were analyzed for each branchio-oto-renal syndrome genotype subpopulation and for controls. RESULTS:-branchio-oto-renal syndrome subset and all controls had no offset and a turn alignment ratio of >0.476. CONCLUSIONS:-branchio-oto-renal syndrome and from individuals without branchio-oto-renal syndrome or sensorineural hearing loss. The turn alignment ratio is a reliable and objective metric that can aid in the imaging evaluation of branchio-oto-renal syndrome.

Knowledge of anatomy is essential to the understanding of disease and conditions of the oral cavity and salivary glands. This article is intended to serve as an overview of the oral cavity, its subsites, and that of the neighboring salivary glands. The authors cover the anatomy of the lips, tongue, floor of mouth, hard palate, teeth, various mucosal areas, and salivary ducts. When appropriate, radiological imaging along with figures serves as a companion to highlight the clinical relevance and practical applications of specific anatomic locations.

OBJECTIVE:This study aimed to quantify the adenoidal-nasopharyngeal ratio (ANR) in a cohort of healthy adults on cone beam computed tomography (CT) using the Fujioka method, which is a reproducible measure of adenoid size and nasopharyngeal patency. METHODS:Electronic health records and maxillofacial cone beam CT in 202 consecutive patients aged 16 years and older were retrospectively reviewed. Patients with a history of adenoidectomy, sinonasal disease, lymphoproliferative disorders, and cleft palate were excluded from the study. The midsagittal reconstructed cone beam CT image was used to determine the ANR. Statistical analysis was conducted using 1-way analysis of variance. RESULTS:Of the 202 subjects, 131 were female and 71 were male. The mean ± SD subject age was 45.43 ± 20.79 years (range, 16-91 years). The mean ± SD ANR in all subjects was 0.22 ± 0.13 (range, 0.03-0.75) and in each decade of adult life was as follows: younger than 21 years, 0.39 ± 0.12; 21 to 30 years, 0.29 ± 0.11; 31 to 40 years, 0.21 ± 0.09; 41 to 50 years, 0.20 ± 0.07; 51 to 60 years, 0.16 ± 0.10; 61 to 70 years, 0.13 ± 0.05; 71 to 80 years, 0.12 ± 0.05; 81 to 90 years, 0.11 ± 0.04; and 91 years or older, 0.10 ± 0. The differences in mean ANR among the age subgroups were statistically significant (P < 0.001). CONCLUSIONS:The mean ANR gradually decreased from 0.39 in the second decade of life to 0.16 in the sixth decade of life and plateaued at approximately 0.10 thereafter.

Various anatomic structures and variants in the temporal bone are potential radiological mimics and surgical hazards. The imaging features of normal variants and lesions with similar imaging appearance are presented in this article. Throughout the article, salient features that can help elucidate the distinguishing features between mimics and imaging pitfalls are presented.

This article discusses mimics, anatomic variants, and pitfalls of imaging of the sinonasal cavity, orbit, and jaw. The authors discuss clinical findings and imaging pearls, which help in differentiating these from one another.