Mohammed Al Washahi

Background: Odontogenic carcinoma with dentinoid (OCD) is a rare, poorly characterised tumour not yet included in the WHO classification of head and neck tumours. We report a rare case of OCD involving the temporal bone. Case presentation: A 35-year-old male presented with longstanding facial nerve paralysis and progressive hearing loss. Radiological investigation revealed an erosive mass in the temporal bone. The tumour was successfully resected, and definitive histopathological analysis showed a picture of OCD. The patient received adjuvant radiotherapy and remains under close surveillance for recurrence. Conclusions: This case broadens the anatomical spectrum of OCD and highlights the need to consider odontogenic tumours in the differential diagnosis of temporal bone lesions, despite their rarity at this site.

Background and Objectives: Frontal recess cells (FRCs) are key anatomical variants influencing frontal sinus drainage and disease. The International Frontal Sinus Anatomy Classification (IFAC) provides a standardized system for their identification. The baseline data on FRC prevalence and its association with sinusitis in Middle Eastern populations remain limited. This study aimed to assess the prevalence, laterality, and clinical relevance of FRCs in an adult Omani population using IFAC criteria. Materials and Methods: Computed tomography (CT) scans of 488 sides from 244 adult Omani patients were retrospectively reviewed to identify the FRCs according to IFAC. A total of 123 patients were found to have sinusitis: bilateral in 37 patients, right-sided in 38 patients, and left-sided in 48 patients. The prevalence of FRCs, along with their laterality and gender differences, was evaluated. Furthermore, the association between FRCs and sinusitis was analyzed using a chi-square test, followed by multivariable logistic regression analysis. Results: Among overall subjects (244 patients; 488 sides), agger nasi cells (79.5%, n = 388) and supra bulla cells (64.1%, n = 313) were the most prevalent cell types, whereas frontal septal cells (8.8%, n = 43) were the least common. Among study subjects (n = 244), laterality differences in FRC frequency were observed in the frontal septal cells, with a higher frequency of cells on the right side (p = 0.01), while no significant differences were found in other cell types. The presence of supra agger frontal cells (OR = 1.544, 95% CI: 1.02–2.23, p = 0.03) was positively correlated with sinusitis, while the presence of supra bulla cells was inversely associated with frontal sinusitis (OR = 0.61, 95% CI: 0.41–0.93, p = 0.01). The presence of FRC type was not significantly associated with the degree of sinusitis (p > 0.05). Significant gender differences were observed in supra orbital ethmoid cells (p = 0.01), with a male predominance. Conclusions: This study provides baseline data on the prevalence of FRCs in the Omani population. The presence of supra agger frontal cells appears to be associated with frontal sinusitis. No statistically significant gender- or laterality-associated differences were observed in most FRC types. Preoperative identification of supra agger frontal cells may facilitate effective surgical planning, particularly for endoscopic sinus surgery.

Objectives: Incidental detection of superior semicircular canal dehiscence (SSCD) in patients without symptoms may lead to misinterpretation if not correlated with clinical presentation, examination findings, and vestibular function testing. This study aimed to assess the rate of radiological SSCD in the asymptomatic Omani population, as the first study of its kind in the country and the Gulf region. Methods: A retrospective review was conducted of all asymptomatic patients who underwent high-resolution computed tomography (HRCT) of the temporal bones at a tertiary care facility between 2017 and 2021. Dedicated consultant neuroradiologists evaluated both superior semicircular canals (SSCs) for evidence of dehiscence. Results: Nineteen of 470 ears showed radiological SSCD, giving a prevalence of 4.1% (95% confidence interval = 2.1–8.1). Seven patients (14 ears) had bilateral dehiscence. The mean defect size was 1.3 mm. Females constituted 52% of the 19 patients, and no significant gender difference was observed (P = 0.68). Conclusion: Radiological SSCD was found in 4.1% of asymptomatic patients on HRCT, comparable to previous reports and substantially higher than post-mortem estimates of asymptomatic SSCD. Therefore, cautious interpretation of HRCT findings is recommended in asymptomatic individuals, with consideration of clinical and audiovestibular assessments.

Chronic rhinosinusitis (CRS) can have a significant impact on quality of life. With persistent symptoms and the failure of initial medical treatments, surgical management is indicated. Despite the excellent results of endoscopic sinus surgery for persistent CRS, it is quite a challenging procedure for frontal sinusitis given the complex anatomy and location of the frontal sinus. Frontal recess cells significantly contribute to the complexity of the frontal sinus, and numerous studies have sought to establish their association with sinusitis. This review offers a comprehensive understanding of frontal recess cells, their different classifications, their prevalence among different populations, and their relationship to sinusitis. After an extensive review of the current literature, the International Frontal Sinus Anatomy Classification (IFAC) is the most recent classification method and a preferred practical preoperative assessment tool. Although the agger nasi cell is the most prevalent cell among all reported populations, ethnic variations are still influencing the other cells’ distribution. Studies are inconsistent in reporting a relationship between frontal recess cells and sinusitis, and that is mainly because of the differences in the classification methods used. More research using a standardized classification method is needed to understand the association between frontal recess cells and sinusitis.

Chronic rhinosinusitis (CRS) can have a significant impact on quality of life. With persistent symptoms and the failure of initial medical treatments, surgical management is indicated. Despite the excellent results of endoscopic sinus surgery for persistent CRS, it is quite a challenging procedure for frontal sinusitis given the complex anatomy and location of the frontal sinus. Frontal sinus cells significantly contribute to the complexity of the frontal sinus, and numerous studies have sought to establish their association with sinusitis. This review offers a comprehensive understanding of the frontal sinus cells, their different classifications, their prevalence among different populations, and their relationship to sinusitis. After an extensive review of the current literature, the International Frontal Sinus Anatomy Classification (IFAC) is the most recent classification method and a preferred practical preoperative assessment tool. Although the Agger Nasi Cell is the most prevalent cell among all reported populations, ethnic variations are still influencing the other cells' distribution. Studies are inconsistent in reporting a relationship between frontal sinus cells and sinusitis, and that is mainly because of the difference in the classification method used. More research using a standardized classification method is needed to understand the association between frontal sinus cells and sinusitis.

The COVID-19 pandemic, driven by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has currently infected more than 61 million people and caused the death of more than 1.4 million around the world (November 2020 figures). As a result, many countries and health organizations have had to investigate the reasons for the pandemic and improve their health care programs to cope with the emergency while trying to develop an effective vaccine.

Background: COVID-19 has heterogeneous manifestations, though one of the most common symptoms is a sudden loss of smell (anosmia or hyposmia). We investigated whether olfactory loss is a reliable predictor of COVID-19. Methods: This preregistered, cross-sectional study used a crowdsourced questionnaire in 23 languages to assess symptoms in individuals self-reporting recent respiratory illness. We quantified changes in chemosensory abilities during the course of the respiratory illness using 0-100 visual analog scales (VAS) for participants reporting a positive (C19+; n=4148) or negative (C19-; n=546) COVID-19 laboratory test outcome. Logistic regression models identified singular and cumulative predictors of COVID-19 status and post-COVID-19 olfactory recovery. Results: Both C19+ and C19-groups exhibited smell loss, but it was significantly larger in C19+ participants (mean±SD, C19+: -82.5±27.2 points; C19-: -59.8±37.7). Smell loss during illness was the best predictor of COVID-19 in both single and cumulative feature models (ROC AUC=0.72), with additional features providing negligible model improvement. VAS ratings of smell loss were more predictive than binary chemosensory yes/no-questions or other cardinal symptoms, such as fever or cough. Olfactory recovery within 40 days was reported for ∼50% of participants and was best predicted by time since illness onset. Conclusions: As smell loss is the best predictor of COVID-19, we developed the ODoR-19 tool, a 0-10 scale to screen for recent olfactory loss. Numeric ratings ≤2 indicate high odds of symptomatic COVID-19 (4<OR<10), which can be deployed when viral lab tests are impractical or unavailable.