The association of frontal recess anatomy and mucosal disease on the presence of chronic frontal sinusitis: a computed tomographic analysis

CT analysis of frontal recess air cell and fluid dynamics simulation of frontal sinus in people with different frontal sinus development after Draf1-3 surgery

OBJECTIVE

To explore the effects of Draf1-3 on frontal sinus airflow and frontal sinus irrigation in people with different frontal sinus development METHODS: The development of the frontal sinus and the distribution of the frontal recess cells were evaluated by CT scan in 150 adults (300 sides). The airflow changes into the frontal sinus and frontal recess after Draf were analyzed by Fluent software under a steady state and quiet inspiratory state. Nasal irrigation after Draf in adults with well-developed frontal sinus was simulated using 120 mL saline at a rate of 12 mL/s in a position at 45° to observe the changes in transient flow distribution.

RESULTS

The moderately developed type of the frontal sinus was the most common. The airflow patterns in the frontal sinus and frontal recess in the moderate development group were laminar, while several large vortexes were formed between the frontal sinus and frontal recess in the well-development group. The Draf exerted more significant effects on the patterns, pressure, and velocity of the airflow in the frontal sinus and frontal recess in the well development group than in the moderate development group. The volume fraction of saline in the frontal sinus increased significantly from Draf1 to Draf3, and the time required for a complete infiltration of saline in the frontal sinus mucosa was significantly reduced.

CONCLUSIONS

Draf1-3 has different effects on the airflow field of the frontal sinus with different developmental types; and Draf1-3 can significantly improve the postoperative flushing of the frontal sinus.

Does Frontal Recess Cell Variation Associate with the Development of Frontal Sinusitis? A Narrative Review

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.

Radiological anatomical variations of the lateral nasal wall and anterior skull base amongst different populations: A systematic review and meta-analysis

OBJECTIVES

To determine the anatomical variations of the lateral nasal wall and anterior skull base amongst populations in different geographical regions.

DESIGN

Systematic review and meta-analysis.

METHODS

Using PRISMA guidelines, SCOPUS and PUBMED databases were searched from inception until 1 March 2022. The regions and populations identified were from Europe, Asia, Middle East, Australia-New Zealand-Oceania, South America, North America and Africa. Random-effects model was used to estimate the pooled prevalence with 95% confidence intervals (CIs). Heterogeneity was assessed using the I² statistic and Cochran's Q test.

MAIN OUTCOME MEASURES

Anatomical variations of the lateral nasal wall and anterior skull base confirmed by computed tomography scan.

RESULTS

Fifty-six articles were included with a total of 11 805 persons. The most common anatomical variation of the ostiomeatal complex was pneumatization of the agger nasi (84.1%), olfactory fossa was Keros type 2 (53.8%) and ethmoids was asymmetry of the roof (42.8%). Sphenoethmoidal and suprabullar cells have a higher prevalence in North Americans (53.7%, 95% CI: 46.00-61.33) while asymmetry of ethmoid roof more common in Middle Easterns (85.5%, 95% CI: .00-100). Bent uncinate process has greater prevalence in Asians while supraorbital ethmoid cells and Keros type 3 more common in non-Asians. The overall studies have substantial heterogeneity and publication bias.

CONCLUSION

Certain anatomic variants are more common in a specific population. The 'approach of analysis' plays a role in the prevalence estimates and consensus should be made in future studies regarding the most appropriate 'approach of analysis' either by persons or by sides.

The Relationship Between the Width of the Frontal Recess and the Frontal Recess Cells in Japanese Patients

Objective

The agger nasi cell (ANC) is an easily identifiable landmark when approaching the frontal sinus. The success of endoscopic frontal sinus surgery may be influenced by the width of the frontal recess (FR). The aim of this study is to examine the relationship between the FR width and the ANC size in Japanese patients. In addition, the effect of various frontal recess cells (FRCs) on the development of frontal sinusitis has been examined.

Materials and methods

Multiplanar computed tomography (CT) scans of the nasal cavities and paranasal sinuses in 95 patients (190 sides) before endoscopic sinus surgery were reviewed. The presence of FRCs, the thickness of the frontal beak (FB), the ANC size, and the anterior-to-posterior (A-P) length of the frontal isthmus (FI) and FR were evaluated in patients with and without frontal sinusitis.

Results

The prevalence of the ANC, frontal cell types 1, 2, 3, and 4, frontal bullar cell (FBC), suprabullar cell, supraorbital ethmoid cell, and interfrontal sinus septal cell was 85.3%, 11.6%, 0%, 7.9%, 0%, 25.3%, 45.8%, 16.8%, and 15.3%, respectively. The ANC volume showed a significant positive correlation with the A-P length of the FI and FR. The incidence of frontal sinusitis in the patients with FBCs was significantly higher than that without FBCs.

Conclusion

A large ANC offers a greater potential to facilitating the approach to the frontal sinus because of the extensiveness of the FR in Japanese patients. The presence of FBCs may be related to a higher incidence of frontal sinusitis.

Lateral frontoethmoidal cell obstructing frontal sinus drainage pathway - report of six cases

The European Anatomical Position Paper on the Anatomical Terminology of the Internal Nose and Paranasal Sinuses distinguishes anterior, posterior, medial and lateral frontoethmoidal cells. The lateral cells have not been characterized yet. Other classifications (Lee and Kuhn, International Frontal Sinus Anatomy Classification) neglect them. The aim of this study is to describe lateral frontoethmoidal cells in rhinosinusitis patients.

METHOD

Analysis of medical records and computed tomography (CT) examinations using multiplanar reconstruction with adjustable planes. The lateral cell extending between the frontal beak and the skull base pushing the frontal sinus drainage pathway medially/anteromedially was identified in 6 patients. These cells could not be classified as anterior, posterior or medial according to existing classifications. Four patients were operated on previously due to sinonasal symptoms. The lateral frontoethmoidal cell is an underestimated anatomical variation that may contribute to the persistence of inflammatory disease and can be easily overlooked preoperatively.

Outcomes of chronic frontal sinusitis treated with ethmoidectomy: a prospective study

BACKGROUND

In medically refractory chronic frontal sinusitis, ethmoidectomy without instrumentation of the frontal ostium may resolve frontal disease. Our aim was to determine the efficacy of ethmoidectomy alone for the treatment of chronic frontal sinusitis.

METHODS

Adults with chronic rhinosinusitis prospectively enrolled in a multicenter study who demonstrated frontal sinusitis on computed tomography were divided into 2 groups: (1) endoscopic sinus surgery (ESS) incorporating ethmoidectomy, but excluding frontal sinusotomy; and (2) ESS incorporating frontal sinusotomy. The primary outcome was improvement in 22-item Sino-Nasal Outcome Test (SNOT-22) scores. Secondary outcomes included endoscopic scores and use of corticosteroids and antibiotics.

RESULTS

A total of 196 cases undergoing frontal sinusotomy and 30 cases treated with ethmoidectomy without frontal sinusotomy were analyzed and were comparable demographically. The prevalence of nasal polyps, previous ESS, asthma, and aspirin intolerance was more common in the frontal sinusotomy group (p < 0.050). Preoperative endoscopy and computed tomography scores were higher in the frontal sinusotomy group (p ≤ 0.001). Postoperatively, both groups showed comparable SNOT-22 scores with worse endoscopy scores in the frontal sinusotomy group (p = 0.038). Postoperative improvement in SNOT-22 total and subdomain scores was comparable between groups. Nasal endoscopy scores improved to a greater degree in the frontal sinusotomy group (p = 0.023). Duration of postoperative topical steroid use was higher in the frontal sinusotomy group (p = 0.007). Revision surgery was needed in 2.6% of frontal sinusotomy patients and 0% of patients without frontal sinusotomy.

CONCLUSION

The treatment of chronic frontal sinusitis through ethmoidectomy is a potential alternative to frontal sinusotomy achieving similar quality of life (QOL) improvements in patients manifesting less severe sinus disease.