Magnetic Resonance Imaging of Perineural Spread of Head and Neck Cancer.

Perineural tumor spread (PNTS) is one of the important methods of tumoral spread in head and neck cancers. It consists of a complex process that entails the production of certain chemicals or the production of certain cell receptors. Histologic type and primary tumor site play an important role in PNTS. Any nerve could be affected; however, the trigeminal and facial nerves are the most involved nerves. Magnetic resonance imaging and computed tomography detect the primary and secondary signs of PNTS. Functional imaging such as diffusion-weighted imaging and hybrid imaging act as problem-solving techniques.

Spike in Rhino-Orbital-Cerebral Mucormycosis Cases Presenting to a Tertiary Care Center During the COVID-19 Pandemic.

Objective: To determine if there was an increase in the rate of cases presenting with rhino-orbital-cerebral mucormycosis (ROCM) to a tertiary care center during the first wave of the coronavirus disease 2019 (COVID-19) pandemic and the characteristics of the presenting cases. Methods: Retrospective observational study reviewing ROCM cases presenting from March 25 until September 25, 2020. Cases fulfilling the clinical, radiological, and pathological/microbiological criteria for diagnosis with ROCM were included. The number of cases presenting during the designated interval, their COVID-19 status, comorbidities, and clinical presentation were analyzed. The number of cases during the corresponding interval in the previous 3 years was used as reference to detect if there was a recent spike. Results: Of the 12 ROCM cases identified, 5 had a concurrent positive reverse transcription PCR (RT-PCR) test result for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), 1 had a prior positive result, and 6 did not have concurrent nor prior positive test results. Nine of the 12 cases had poorly controlled diabetes mellitus, and 2 cases had a hematological malignancy. All cases had orbital invasion, and eight cases had cerebral invasion. The number of cases identified during the interval is much higher than the numbers presenting in the prior 3 years during equivalent intervals (range, one to two cases) than those reported in the literature in different settings in the pre-pandemic era. Conclusions: There is an increased rate of ROCM cases presenting to our center during the first wave of the COVID-19 pandemic. This is a preliminary report, and further studies are needed to corroborate the findings and explain possible underlying links.

Interreader reproducibility of the Neck Imaging Reporting and Data system (NI-RADS) lexicon for the detection of residual/recurrent disease in treated head and neck squamous cell carcinoma (HNSCC).

BACKGROUND: To evaluate the inter- and intrareader agreement and reproducibility of the NI-RADS scoring system and lexicon with contrast-enhanced computed tomography (CECT) and contrast-enhanced magnetic resonance imaging (CEMRI). METHODS: This retrospective study included 97 CECT and CEMRI scans from 58 treated cases of head and neck squamous cell carcinoma (HNSCC) after the exclusion of head and neck cancers (HNCs) other than SCC and noncontrast and poor quality CT and MRI scans, with a total of 111 primary targets and 124 lymph node (LN) targets. Two experienced readers independently scored the likelihood of residual/recurrence for these targets based on the NI-RADS criteria and filled in report templates for NI-RADS lexicon diagnostic features. Inter- and intraobserver reproducibility was assessed with Cohen's kappa, and the percent agreement was calculated. RESULTS: Almost perfect interreader agreement was found for the final NI-RADS category of the primary lesions and LNs, with K = 0.808 and 0.806, respectively. Better agreement was found for CT than for MRI (K = 0.843 and 0.77, respectively, P value 0.001). There was almost perfect agreement for excluding tissue enhancement (K = 0.826, 95% CI = 0.658-0.993, P value 0.001), with a percent agreement of 96.4%, and substantial agreement for discrete nodular and diffuse mucosal enhancement (K = 0.826, 95% CI = 0.658-0.993, P value 0.001), with a percent agreement of 96.4%. There was fair agreement for focal mucosal nonmass and deep ill-defined enhancement. The intrareader agreement was almost perfect for most of the rated features (K ranging from 0.802 to 1), with the exception of enlarging discrete nodule/mass and focal mucosal nonmass-like enhancement, which had substantial intraobserver agreement (K ranging from 0.768 to 0.786). CONCLUSION: The individual features of NI-RADS show variable degrees of confidence; however, the overall NI-RADS category was not significantly affected.

Neck Imaging Reporting and Data System: What Does Radiologist Want to Know?

The aim of this work was to review Neck Imaging Reporting and Data System (NI-RADS) that was designed for reporting and surveillance of head and neck cancer after therapy and their subsequent management. The categories of NI-RADS can be designated as belonging in 1 of the 4 categories: negative; low suspicion; high suspicion; and definite recurrence. Lexicon of NI-RADS-1 shows nonmass-like distortion of soft tissues, NI-RADS-2 lesions divided into mucosal (2A) versus deep (2B) abnormalities, NI-RADS-3 primary site can either be a submucosal or deep lesion, and NI-RADS-4 is a biopsy-proven residual or recurrent disease. The NI-RADS Lexicon of radiology reporting categories linked to management protocols and surveillance for these patients. Neck Imaging Reporting and Data System is to provide guidance for next-imaging decisions either a follow-up period, biopsy, or surgery.

Magnetic resonance imaging of developmental facial paresis: a spectrum of complex anomalies.

PURPOSE: Despite its clinical implications, the MRI features of developmental facial paresis (DFP) were described in a few case reports. This study aims to describe MRI features of DFP in relation to the embryological development with a proposed radiological new grading system. METHODS: The clinical records and MRI of the brain and internal auditory canal of 11 children with DFP were retrospectively reviewed. The following sequences were analyzed: axial, oblique sagittal SPACE of the internal auditory canal and brainstem; axial T2, T1WI and coronal T2WI of the brain. The severity of the maldevelopment of the seventh nerve was graded from 0 to 4: 0 = no abnormalities, 1 = unilateral facial nerve hypoplasia, 2 = unilateral facial nerve aplasia, 3 = aplasia or hypoplasia involving facial nerves on both sides, and 4 = facial nerve aplasia or hypoplasia associated with other cranial nerve palsy. RESULTS: Isolated facial nerve palsy was diagnosed in seven patients. It was of grade 1 in five and grade 3 in two. Hypoplasia of the nerve with interrupted course was encountered in two cases. Other associated cranial nerve abnormalities (grade 4) were seen in four patients; two of them were diagnosed previously as Moebius syndrome. In addition to inner ear anomalies, middle and external ear and parotid gland anomalies were described. CONCLUSION: To our knowledge, this is the largest series of patients with DFP that represents a continuum of isolated and combined malformations. Understanding of embryological basis can give insights into the anomalous development of the facial nerve.