Evaluation of the Sensitivity of Metabolic Profiling by Rapid Evaporative Ionization Mass Spectrometry: Toward More Radical Oral Cavity Cancer Resections.

Radical resection for patients with oral cavity cancer remains challenging. Rapid evaporative ionization mass spectrometry (REIMS) of electrosurgical vapors has been reported for real-time classification of normal and tumor tissues for numerous surgical applications. However, the infiltrative pattern of invasion of oral squamous cell carcinomas (OSCC) challenges the ability of REIMS to detect low amounts of tumor cells. We evaluate REIMS sensitivity to determine the minimal amount of detected tumors cells during oral cavity cancer surgery. A total of 11 OSCC patients were included in this study. The tissue classification based on 185 REIMS ex vivo metabolic profiles from five patients was compared to histopathology classification using multivariate analysis and leave-one-patient-out cross-validation. Vapors were analyzed in vivo by REIMS during four glossectomies. Complementary desorption electrospray ionization-mass spectrometry imaging (DESI-MSI) was employed to map tissue heterogeneity on six oral cavity sections to support REIMS findings. REIMS sensitivity was assessed with a new cell-based assay consisting of mixtures of cell lines (tumor, myoblasts, keratinocytes). Our results depict REIMS classified tumor and soft tissues with 96.8% accuracy. In vivo REIMS generated intense mass spectrometric signals. REIMS detected 10% of tumor cells mixed with 90% myoblasts with 83% sensitivity and 82% specificity. DESI-MSI underlined distinct metabolic profiles of nerve features and a metabolic shift phosphatidylethanolamine PE(O-16:1/18:2))/cholesterol sulfate common to both mucosal maturation and OSCC differentiation. In conclusion, the assessment of tissue heterogeneity with DESI-MSI and REIMS sensitivity with cell mixtures characterized sensitive metabolic profiles toward in vivo tissue recognition during oral cavity cancer surgeries.

Detection of Bone Marrow Edema in the Head and Neck With Dual-Energy CT: Ready for Clinical Use?

OBJECTIVE. The aim of this study is to evaluate the ability of dual-energy CT (DECT) to identify bone marrow edema (BME) in the head and neck region in comparison with MRI as the standard of reference. MATERIALS AND METHODS. A total of 33 patients who underwent imaging between February 2016 and February 2018 were included in this retrospective study. All patients underwent both DECT and MRI for head and neck abnormalities. Two radiologists independently visually assessed virtual noncalcium (VNCa) reconstructions with color-coded maps for the presence of BME. STIR or T2-weighted MRI reconstructions with fat suppression were used as the standard of reference for BME. Subjective quality assessment and severity of metal artifacts were scored on both imaging modalities. RESULTS. BME was detected in 18 patients on DECT compared with 20 patients on MRI. Most BME seen on DECT was located in the mandible. VNCa DECT images had a sensitivity, specificity, positive predictive value, and negative predictive value for BME of 85%, 92%, 94%, and 80% respectively, using MRI as the reference. The quality of the images was rated as excellent to moderate in 94% of the patients for VNCa DECT compared with 82% of the patients for MRI, but this difference was not statistically significant. Significantly more metal artifacts were scored on the mixed DECT images than on the MR images, but these artifacts did not interfere with diagnosis. CONCLUSION. BME detection in the head and neck region seems possible with VNCa DECT images and has the potential to provide an alternative for MRI in clinical practice.

[Odontogenic infection as cause of orbital cellulitis]. / Een dentale oorzaak van orbitale cellulitis.

BACKGROUND: Orbital cellulitis is a potentially life-threatening condition. Compression of the optical nerve can cause total or partial loss of vision. Early diagnosis is crucial to prevent complications. In case of a unilateral sinusitis as cause of a unilateral orbital cellulitis complete clinical and dental examination combined with imaging are essential in diagnostics. CASE DESCRIPTION: A 53-year-old man presented with left eye movement impairment, intermittent diplopia and moderate swelling of the left lower eyelid. His diagnosis was post septal orbital cellulitis and despite administration of oral antibiotics no clinical improvement was observed. Orbital imaging by CT could not exclude a dental cause of his unilateral maxillary sinusitis. He was referred to the department of oral and maxillofacial surgery where clinical examination showed a dental cause. After removal of two decayed upper molars a complete recovery was accomplished. CONCLUSION: Odontogenic causes for unilateral orbital cellulitis should always be considered in diagnostics in adults. Clinical presentation and dental examination combined with adequate imaging can confirm the diagnosis.

Bone invasion by oral squamous cell carcinoma: Molecular alterations leading to osteoclastogenesis - a review of literature.

Oral squamous cell carcinoma (OSCC) is a growing problem globally. OSCC often arises in close anatomical relation to the jaws and may invade the bone. Bone invasion by OSCC has major implications on tumor staging, choice of treatment, outcome, and quality of life. The difference in cortical or medullary bone invasion has implications for these factors. Treatment protocols used for cortical and medullary invasion differ worldwide. By researching possible pathways a more molecular-based clinical staging and tailor-made therapy can be useful for patients with bone invasion by OSCC. An important molecular step in bone invasion seems to be the activation of osteoclasts. Several direct and indirect pathways can activate osteoclasts. Microbial infections, hypoxia, and the immune system could be of interest.

Dual-Energy CT in Head and Neck Imaging.

PURPOSE OF REVIEW: To explain the technique of Dual-energy CT (DECT) and highlight its applications and advantages in head and neck radiology. RECENT FINDINGS: Using DECT, additional datasets can be created next to conventional images. In head and neck radiology, three material decomposition algorithms can be used for improved lesion detection and delineation of the tumor. Iodine concentration measurements can aid in differentiating malignant from nonmalignant lymph nodes and benign posttreatment changes from tumor recurrence. Virtual non-calcium images can be used for detection of bone marrow edema. Virtual mono-energetic imaging can be useful for improved iodine conspicuity at lower keV and for reduction of metallic artifacts and increase in signal-to-noise ratio at higher keV. SUMMARY: DECT and its additional reconstructions can play an important role in head and neck cancer patients, from initial diagnosis and staging, to therapy planning, evaluation of treatment response and follow-up. Moreover, it can be helpful in imaging of infections and inflammation and parathyroid imaging as supplementary reconstructions can be obtained at lower or equal radiation dose compared with conventional single energy scanning.