Factors in the pathogenesis of tumors of the sphenoid and maxillary sinuses: a comparative study

Forensic Identification from Three-Dimensional Sphenoid Sinus Images Using the Iterative Closest Point Algorithm

Forensic identification of human remains is crucial for legal, humanitarian, and civil reasons. Wide heterogeneity in sphenoid sinus morphology can be used for personal identification. This study aimed to propose a new protocol for personal identification based on three-dimensional (3D) reconstruction of sphenoid sinus CT images using Iterative Closest Point (ICP) algorithm. Seven hundred thirty-two patients which consisted of 348 females and 384 males were retrospectively included. The study sample includes 732 previous images as a source point set and 743 later ones as a scene target set. The sphenoid sinus computed tomography (CT) images were processed on a workstation (Dolphin imaging) to obtain 3D images and stored as a file format of Stereo lithography (.STL). Then, a Python library vtkplotter was used to transform the STL format to PLY format, which was adapted to Point Cloud Library (PCL). The ICP algorithm was used for point clouds matching. The metric Rank-N recognition rate was used for evaluation. The scene target set of 743 individuals was compared with the source point set of 732 individual models and achieved Rank-1 accuracy of 96.24%, Rank-2 accuracy of 99.73%, and Rank-3 accuracy of 100%. Our results indicated that the 3D point cloud registration of sphenoid sinuses was useful for assessing personal identification in forensic contexts.

Septum submucosal glands exhibit aberrant morphology and reduced mucin production in chronic rhinosinusitis

BACKGROUND

Chronic rhinosinusitis (CRS) is characterized by significant accumulation and thickening of mucus in the sinonasal cavities. One contributor of aberrant mucus production and impaired mucociliary clearance (MCC) is altered function of the sinonasal submucosal glands (SMGs), yet contributions of SMGs to upper airway disease initiation and progression remain unknown. The objective of this study was to characterize the morphology and secretory cell identities of the nasal septum SMGs in both healthy and CRS adults.

METHODS

Biopsies from adult participants with CRS without nasal polyps (CRSsNP, n = 4), CRS with nasal polyps (CRSwNP, n = 8), and non-CRS controls (n = 14) were collected from the posterior septum. Glandular morphology and mucus markers were investigated using histological techniques and high-resolution confocal microscopy.

RESULTS

Analysis revealed a significant decrease in gland density in the posterior septum of CRSsNP (28% ± 6.15%) and CRSwNP (23% ± 3.09%) compared to control participants (53% ± 1.59%, p < 0.0001). Further analysis of the CRS SMG secretory function revealed an overall decrease in Mucin 5B+ gland mucus being produced. Dilated and cystic ductal structures filled with inspissated mucus were also common to CRS glands.

CONCLUSION

Here, we describe a significant alteration in SMG structure and function in the adult CRS posterior septum suggesting reduced gland contribution to MCC. The SMGs of both the nose and sinuses may represent targets for future therapeutic approaches.

A Rare Case of Metastases to Paranasal Sinus From Colonic Adenocarcinoma

Metastases of malignant tumors to the nasal cavity and paranasal sinuses are very rare. Metastases to these locations are usually solitary and produce similar symptoms to those of a primary sinonasal tumor. Pain, nasal obstruction, and epistaxis are the most common symptoms. Although any malignancy could potentially lead to metastasis to the paranasal sinuses, colo-rectal malignancy metastasizes to this site is rare. We report a case of metastatic adenocarcinoma of colorectal origin to the paranasal sinuses in a 55-year-old female who was initially diagnosed with adenocarcinoma of the colon with lung and liver metastasis. She subsequently developed metastasis to left ethmoidal and sphenoidal sinuses during treatment. A histologic study of the surgical specimen from the sinonasal cavity demonstrated a tumor identical to the patient's prior primary tumor of the colon. The sinonasal neoplastic tissue showed marked positivity for carcinoembryonic antigen and expressed cytokeratin 20, which differentiates metastatic colonic adenocarcinoma from primary intestinal-type adenocarcinoma (ITAC). She received palliative radiation therapy but died three months after the diagnosis. These subsets of patients have a poor prognosis. In the majority of patients, palliative therapy is the only possible treatment option. Nevertheless, whenever possible, surgical excision either alone or combined with radiotherapy may be useful for palliation of symptoms and, rarely, to achieve prolonged survival.

Microscopic study of certain age-related structural changes of maxillary sinus lining epithelium in albino rats

Mucociliary clearance is essential to maintain the defense function of the maxillary sinus; however, no literatures described the age changes in its lining epithelium. Therefore, the current work sought to describe the morphological postnatal age-related changes of maxillary sinus lining epithelium in rats using light, transmission, and scanning electron microscopes. Eighteen albino rats were divided into six groups according to their ages: 2-week-old, 1-month-old, 2-month-old, 3-month-old, adults, and senile rats. One-month-old-rats' group was the first to have recognizable maxillary sinus cavities that were lined by either single flat cellular layer or two distinct epithelial layers. These cells were devoid of microvilli and cilia, none of them showed evidence of differentiation into identifiable cell types. In 2- and 3-month-old rats, the mucosa of maxillary sinus started to be lined with pseudostratified epithelium with apparent increase in both microvilli and cilia. The first indication of goblet cell differentiation was observed in 3-month-old-rats. In the adult rats, the sinuses became completely lined by mature respiratory epithelium. However, in senile rats the epithelium exhibited polyps with clumped cilia and some areas of stratification and desquamation. Goblet cells were scanty and degenerating. The impaired mucociliary components (epithelium, cilia, and goblet cells' mucus) found in young and old ages of the current work might be correlated to human to explain predisposition of rhino-sinusitis in these age groups.

Isolated sphenoid sinus disease

Disease of the sphenoid sinus is often vague and nonspecific in its clinical presentation. Therefore, the otolaryngologist must maintain a high index of suspicion when evaluating patients who present with such nonspecific symptoms. A thorough understanding of the radiologic characteristics of sphenoid sinus disease is essential in the proper evaluation and management of these patients.