Role of Sinonasal Anatomic Variations in the Development of Maxillary Sinusitis: A Cone Beam CT Analysis

The Ethmomaxillary Sinus-A False Duplicate Maxillary Sinus

Functional endoscopic sinus surgery consistently benefits from good anatomical knowledge and modern imaging techniques. Ethmoid air cells migrate in specific topographical sites near the ethmoid. Posterior ethmoid air cells that descend into the maxillary sinus (MS) are ethmomaxillary sinuses (EMSs) that into the superior nasal meatus. Few previous studies found EMSs in 0.68% to 16.48% of cases. An EMS differs from a Haller's infraorbital cell nearing the ethmoidal infundibulum. A posterior ethmoid air cell intercalated between the ethmoid, MS and sphenoidal sinus is a Sieur's cell, but it could also be regarded as an EMS. An EMS should be discriminated from a maxillary recess of the sphenoidal sinus. An EMS could determine Onodi's maxillary bulla into the MS. The false duplicate MS described by Zuckerkandl consists of a MS draining into the middle nasal meatus adjoined by an EMS draining into the superior nasal meatus. These are separated by the ethmomaxillary septum. The latter may be confused with an intrasinus septum of the MS if the drainage pathways are not adequately documented. Therefore, a case-by-case anatomic identification of the pneumatic spaces nearing the MS should be performed before surgical endoscopic approaches of the nose and sinuses.

Evaluation of osteomeatal complex by cone-beam computed tomography in patients with maxillary sinus pathology and nasal septum deviation

BACKGROUND

This study aimed to determine if there is a relationship between the presence of maxillary sinus pathology, nasal septum deviation and various lengths of the osteomeatal complex.

METHODS

A total of 223 CBCT images were included in the study. The lengths of the osteomeatal complex (maxillary sinus ostium width, infundibulum length, maxillary sinus ostium height) were analyzed. The presence of maxillary sinus pathology, nasal septum deviation, age, sex, right-left, septum deviation level, and the relationship between pathology level and all variables were evaluated.

RESULTS

The average maxillary sinus ostium width, ostium height and infundibulum length were 3.06 ± 0.70 mm, 30.10 ± 5.43 mm and 8.82 ± 1.86 mm, respectively. Ostium width was significantly higher in the healthy group than in the groups evaluated in the presence of deviation and pathology. A significant difference was found in infundibulum length only between the healthy condition and the condition evaluated in the presence of deviation. No significant difference was observed between the groups in terms of ostium height. In all groups, ostium height and infundibulum length were significantly higher in men than in women. The age group with the highest average ostium height was found in the 35-44 age group (p < 0.001).

CONCLUSION

Identifying normal and abnormal conditions in the osteomeatal complex area is important for diagnosing the cause of a patient's complaint, guiding the surgical procedures to be performed, and preventing possible complications that may arise during surgical procedures.

Anatomical variations and abnormalities of the maxillary region and clinical implications: A systematic review and metaanalysis

OBJECTIVE

The objective of this review is to investigate and analyze the anatomical variations present in the maxillary sinus (MS), through the examination of the prevalence of these variations, as well as the corresponding prevalence of clinically significant pathologies and complications associated with them.

METHODS

The search process was carried out in the following databases; MEDLINE, SCIELO, WOS, CINHAL, SCOPUS, and GOOGLE SCHOLAR, using as search terms; "Maxillary bone," "Maxillary sinus," "Paranasal sinus," "Anatomical variations," "Sinusitis" and "Clinical anatomy."

RESULTS

A total of 26 articles and 12969 samples were included, from which 12,594 subjects had their sex recorded giving a total of 5802 males and 6792 females. The variants reported by the included were Haller cells, Concha Bullosa, Number of septa, Hypoplastic sinus, Agger Nasi, Thickening of the MS mucosa, Deviation of the nasal septum, Accessory ostium, and Onodi cells. Among the mentioned, the ones that presented the greatest number of studies (between 8 and 10 studies included) were: the Haller Cells, the Concha Bullosa, and the Number of septa, where prevalence was 0.30, 0.36, 0.39 respectively. These variations can lead to sinusitis, cause some types of tumors, or affect neighboring structures that could be compromised by this variation.

CONCLUSION

As a result, it is certainly complex to distinguish the presence of anatomical variations from pathological abnormalities. Therefore, knowledge of the different variations and their clinical relationships could be a useful asset for clinicians dedicated to this region.

Analysis of risk variables for association with maxillary sinus mucosal thickenings: a cone-beam computed tomography-based retrospective study

PURPOSE

This study aimed to determine which patient-related, anatomical, pathologic, or iatrogenic variables may be directly associated with and which may have a modifying effect on the generation of maxillary sinus (MS) mucosal thickenings.

METHODS

A total of 278 cone-beam computed tomography (CBCT) scans obtained from 114 males and 164 females were evaluated. The protocol included the assessment of 21 candidate variables, of which 18 were bilateral and 3 were unique. The relationship among the study variables and the mucosal thickenings were examined individually and adjusted for confounding using univariate and multivariate binary logistic regression models.

RESULTS

The prevalence of mucosal thickenings was 71.20% at patient level and 53.40% at sinus level. The ostium height > 28.15 mm, the infundibulum length ≤ 9.55 mm, the infundibulum width ≤ 0.50 mm, along the occurrence of periapical lesions and slight-to-severe periodontal bone loss acted as strong/independent risk variables for MS mucosal thickenings. Confounding and interaction relationships between MS height and depth, and between the alveolar process type and the presence of foreign materials with respect to age stratum > 47.50 years might be also associated with the mucosal thickenings.

CONCLUSIONS

While increased ostium height, decreased infundibulum length/width, the presence of periapical lesions and periodontal involvement might be the foremost indicator variables for MS mucosal thickenings, there are synergistic relationships among the increased sinus height and depth as well as aging regarding atrophic/partially atrophic alveolar process status and the presence of foreign materials that may be also associated with a greater proportion of these mucosal abnormalities.

Computed Tomographic Comparison of Length, Width and Angulation of Ethmoidal Infundibulum in Patients With and Without Maxillary Sinusitis

Ethmoidal infundibulum (EI) is an important part of the osteomeatal complex, which provides the main pathway for the maxillary sinus drainage. This study aimed to compare the length, width, and angulation of EI in patients with/without maxillary sinusitis using computed tomography (CT). This cross-sectional study evaluated 818 spiral CT scans of patients with/without maxillary sinusitis (n = 409 maxillary sinuses in each group) classified according to the clinical symptoms and the Lund-Mackay score for mucosal thickening. The degree of mucosal thickening (on axial and coronal sections), anatomical variations namely concha bullosa (CB), ethmoidal bulla (EB), and Haller cells (HCs), the form of EI (on coronal sections), the length, width and angulation of EI, and degree of nasal septal deviation (on coronal sections) were all evaluated. Data were analyzed by parametric and non-parametric tests (alpha = 0.05). The frequency of EB (P < 0.001), EI form (P < 0.001) and HC (P = 0.011), and the length and width of EI (P < 0.001) were significantly different in patients with and without maxillary sinusitis. The length and width of EI were significantly correlated with the degree of mucosal thickening (P < 0.01). The frequency of CB (P = 0.002), EB (P < 0.001), and HC (P = 0.002), and the EI form (P < 0.001) were significantly different in groups with different degrees of mucosal thickening. EI was wider and shorter in patients with maxillary sinusitis. By an increase in mucosal thickness, the length of EI decreased while its width increased. Also, the frequency of EB and HC, and the EI form were significantly different in the two groups.

International consensus statement on allergy and rhinology: rhinosinusitis 2021

I.

EXECUTIVE SUMMARY

BACKGROUND: The 5 years since the publication of the first International Consensus Statement on Allergy and Rhinology: Rhinosinusitis (ICAR-RS) has witnessed foundational progress in our understanding and treatment of rhinologic disease. These advances are reflected within the more than 40 new topics covered within the ICAR-RS-2021 as well as updates to the original 140 topics. This executive summary consolidates the evidence-based findings of the document.

METHODS

ICAR-RS presents over 180 topics in the forms of evidence-based reviews with recommendations (EBRRs), evidence-based reviews, and literature reviews. The highest grade structured recommendations of the EBRR sections are summarized in this executive summary.

RESULTS

ICAR-RS-2021 covers 22 topics regarding the medical management of RS, which are grade A/B and are presented in the executive summary. Additionally, 4 topics regarding the surgical management of RS are grade A/B and are presented in the executive summary. Finally, a comprehensive evidence-based management algorithm is provided.

CONCLUSION

This ICAR-RS-2021 executive summary provides a compilation of the evidence-based recommendations for medical and surgical treatment of the most common forms of RS.

[Surgical anatomy of the maxillary sinus]

BACKGROUND

Improved understanding of the microanatomy of the paranasal sinuses, including its individual variations, makes a substantial contribution to current progress in endonasal endoscopic microsurgery. Microanatomy of the sinuses is an active field of present scientific investitations.

MATERIALS AND METHODS

A comprehensive review on microanatomy of the maxillary sinus is presented from the perspective of contemporary endonasal endoscopic microsurgery.

RESULTS

The range of variation of the individual microanatomy of all sections of the maxillary sinus is presented, in particular to minimize secondary sugical tissue trauma, to avoid complications (e.g. on orbital tissues) and as a basis for the prelacrimal access to the maxillary sinus.

CONCLUSION

Improved understanding of the range of microanatomical variations reduced the burden on the patient while opimizing the effectiveness of the necessary surgical manipulations.

Detection of peri-implant bone defects using cone-beam computed tomography and digital periapical radiography with parallel and oblique projection

Purpose

To compare the diagnostic accuracy of cone-beam computed tomography (CBCT) with that of parallel (PPA) and oblique projected periapical (OPA) radiography for the detection of different types of peri-implant bone defects.

Materials and Methods

Forty implants inserted into bovine rib blocks were used. Thirty had standardized bone defects (10 each of angular, fenestration, and dehiscence defects), and 10 were defect-free controls. CBCT, PPA, and OPA images of the samples were acquired. The images were evaluated twice by each of 2 blinded observers regarding the presence or absence and the type of the defects. The area under the receiver operating characteristic curve (AUC), sensitivity, and specificity were determined for each radiographic technique. The 3 modalities were compared using the Fisher exact and chi-square tests, with P<0.05 considered as statistical significance.

Results

High inter-examiner reliability was observed for the 3 techniques. Angular defects were detected with high sensitivity and specificity by all 3 modalities. CBCT and OPA showed similar AUC and sensitivity in the detection of fenestration defects. In the identification of dehiscence defects, CBCT showed the highest sensitivity, followed by OPA and PPA, respectively. CBCT and OPA had a significantly greater ability than PPA to detect fenestration and dehiscence defects (P<0.05).

Conclusion

The application of OPA radiography in addition to routine PPA imaging as a radiographic follow-up method for dental implantation greatly enhances the visualization of fenestration and dehiscence defects. CBCT properly depicted all defect types studied, but it involves a relatively high dose of radiation and cost.

Air spaces neighbouring the infraorbital canal

OBJECTIVE

The infraorbital canal (IOC) courses through the roof of the maxillary sinus (MS). Different grading systems concerning the topography of the IOC have been proposed. Further, it has been suggested that a transantral IOC would be morphologically related to Haller's cells (HCs). However, we hypothesized that this is not necessarily the case. Hence, we aimed to study the anatomical possibilities of the air spaces located medially to the IOC.

MATERIALS AND METHODS

The cone-beam computed tomography (CBCT) files of 40 adult patients were retrospectively evaluated.

RESULTS

The transantral type of IOC was found in 32.5% of patients. The infraorbital recesses of the MS were found medial to the IOC in 20% of patients. As referred to the nasolacrimal canal, these recesses were either prelacrimal (appearing as false isolated air cells) or retrolacrimal (appearing as false HCs). True HCs were found in 10% of patients. They were located medial to the IOC and they drained into the ethmoidal infundibulum (EI), which was distinct from the MS drainage. In 15% of patients, aerated nasolacrimal ducts (NLDs) were found anterior to the EI and medial to the antral angle. They were capable of masquerading either a HC or an infraorbital recess of the MS.

CONCLUSION

Previous classifications of the IOC, which related it to HCs, were reviewed and the evidence was found to be insufficient to assess the HC-related topography of the IOC. Therefore, to achieve the accurate anatomical identification of the air spaces neighbouring the IOC, the infraorbital recesses of the MS, the HCs, and the aerated NLDs should be carefully discriminated within the antero-supero-medial antral angle.