The International Frontal Sinus Anatomy Classification (IFAC) and Classification of the Extent of Endoscopic Frontal Sinus Surgery (EFSS)

Computed Tomographic Study of Frontal Sinus Cells and Opacification as Per the International Frontal Sinus Anatomy Classification

INTRODUCTION

International frontal sinus anatomy classification (IFAC) was introduced in 2016 to standardize the nomenclature of the cells in the frontal recess region, facilitate better communication between surgeons and precision in surgical planning, and improve surgical teaching. This study aims to estimate the radiological prevalence of the different frontal recess cells according to the IFAC and to evaluate the relationship of these cells with the frontal sinus opacification in patients with chronic rhinosinusitis.

METHODS

In this study, 90 participants diagnosed with chronic rhinosinusitis (CRS) who underwent computed tomogram (CT) of the para nasal sinuses were enrolled consecutively. The CT images were were studied in detail using RadiAnt DICOM viewer. The frontal recess cells were grouped as per the IFAC guidelines and their respective prevalence was calculated. The frontal recess cells were grouped as per the Opacification or mucosal thickening within these cells and the frontal sinuses were noted. A multivariate logistic regression analysis was done to evaluate the association between frontal sinus opacification and presence of various IFAC cells.

RESULTS

A total of 640 IFAC cells were documented in 180 sides, of which 326 were anterior cells, 263 were posterior cells and 51 were medial cells. The most prevalent cell was the agger nasi cells(ANC), present in 91.7% of 180 sides, the supra agger nasi cells(SANC), Supra agger nasi frontal cells(SAFC), supra bulla cells(SBC), supra bulla frontal cells(SBFC), supra orbital ethmoidal cells(SOEC) and frontal septal cells(FSC) were present in 47.8%,37.8%, 65.6%,28.9%, 51.1% and 28.3% respectively. There was no significant association of presence of IFAC cells and frontal sinus opacification except for SBFC(p = 0.038). A significantly higher number of diseased frontal recess cells were seen with involved frontal sinuses when compared with non-involved frontal sinuses across all types of IFAC cells.

CONCLUSION

The ANC were the most prevalent among all the IFAC cells and the FSC were the least prevalent. There was no significant association with the presence of different types of IFAC cells and frontal sinus opacification except for SBFC. However, there was a significantly higher number of diseased IFAC cells associated with frontal sinus opacification than in those without frontal sinus opacification.

30° anteriorly tilted CT for visualizing the drainage pathway of the frontal sinus

KEY POINTS

The optimal tilt for anteriorly tilted coronal CT was examined. A 30° anteriorly tilted coronal CT best visualized the frontal sinus drainage pathway.

Dupilumab Improves Facial Pain and Reduces Rescue Treatments in Patients with CRSwNP and Recalcitrant Frontal Sinusitis

Recalcitrant frontal sinusitis in patients with chronic rhinosinusitis and nasal polyps (CRSwNP) has a negative impact on their quality of life due to frontal pain and a high risk of sinus occlusion, thus necessitating antibiotics, systemic corticosteroids, and multiple surgeries. The aim of this study was to assess the efficacy of dupilumab in reducing frontal pain and the need for rescue treatments for recalcitrant frontal sinusitis in patients with CRSwNP. We enrolled a cohort of 10 patients with severe uncontrolled CRSwNP and concomitant recurrent frontal sinusitis associated with severe facial pain measured by MIDAS score who were treated with dupilumab 300 mg every 2 weeks and followed for at least 12 months. The mean MIDAS score decreased from 45.6 ± 10.7 at baseline to 1.3 ± 2.3 at 6 months (p < 0.05). VAS craniofacial pain decreased from 7.3 ± 1.6 at baseline to 1.2 ± 1.5 at 6 months (p < 0.05). No patient needed oral corticosteroids during treatment with dupilumab (p < 0.05), and the use of analgesics decreased from 9.6 ± 3.1 NSAID pills/week in the last 2 months at baseline to 0.6 ± 1.3 at 1 year of follow-up (p < 0.05). Our results demonstrated that use of subcutaneous dupilumab can improve symptom control, including recurrent severe cranio-facial pain, and reduce the need for rescue medical treatments (systemic steroids and NSAID) in patients with severe uncontrolled CRSwNP and concomitant recurrent frontal sinusitis.

Anteriorly Tilted Coronal CT of Paranasal Sinuses for Endoscopic Sinus Surgery

Conventional coronal CT scans of paranasal sinuses, aligned perpendicularly to the nasal floor, often deviate significantly from the endoscopic view during sinus surgery. This discrepancy complicates the interpretation of anatomical structures. In response, we propose the utilization of anteriorly tilted coronal CT slices to enhance anatomical understanding. These slices align more closely with the endoscopic view, fostering an intuitive grasp of paranasal sinus anatomy. This study aims to quantify the tilt of the endoscope to the nasal floor during endoscopic sinus surgery. To figure out the tilt of the endoscopically true coronal slices, we calculated the tilt of the endoscope to the nasal floor in the operative setting by taking pictures of the operation and measuring the image and sagittal CT. Fourteen patients (25 sides of paranasal sinuses) were analyzed. Endoscope tilts to the nasal floor were measured at different anatomical landmarks: 16.2 ± 9.7 degrees (lower edge of ground lamella), 29.8 ± 7.9 degrees (central ground lamella), 62.3 ± 10.1 degrees (most superior part), and 25.6 ± 7.0 degrees (optic canal). In conclusion, we showed the actual tilt of the endoscope to the nasal floor during endoscopic sinus surgery. A 30-degree anteriorly tilted coronal scan for frontal recess and sphenoid sinus is more intuitive than a traditional coronal scan, which helps surgeons understand the complex sinus anatomy.

The Variants of Frontal Recess and Its Effect in the Development and Prevalence of Frontal Sinusitis in Patients in a Tertiary Care Hospital: A Retrospective Observational Study

According to medical literature, the frontal recess' intricate physical structure resembles an inverted funnel. The anatomical structure is not distant from the frontal ostium. Surgery requires a good understanding of the frontal recess architecture because of the intricate anatomy of this relatively small area. The pathophysiological characteristics of frontal sinusitis and the process of sinus ventilation through the sinus ostium have been linked, according to medical literature. Medical studies show that one of the most important factors affecting the amount of drainage in the frontal sinuses is the size of the frontal sinus ostium. Inflammation brought on by frontal recess cells can frequently affect the airflow in the frontal sinuses. The drainage channel of the frontal sinus is stated as narrowing in the current investigation as an observed phenomenon. The aim of this study was to examine the frontal recess changes and how they might affect the emergence of frontal sinusitis. The classification of frontal recesses according to their various categories was the study's principal finding. The investigation of the causal elements that resulted in the development of frontal sinusitis was the study's secondary goal. In a hospital setting, a cohort of 200 patients with sinonasal disorders underwent a retrospective observational research. Over the course of a year, from July 2021 to June 2022, the study participants had evaluations at a tertiary care center. 200 CT PNS images of individuals who fit certain inclusion and exclusion criteria were examined in this study. Using the chi-square test, the study looked into the relationships between several risk factors, including age, gender, and the type of frontal recess. The presence of frontal sinusitis served as the main outcome indicator. This study included a total of 200 participants with a mean age was 43.38 years (± 10.69). There was 146 (73%) male and 54 (27%) female were in the study. Type I frontal recess in 50 (25%), type II in 82 (41%), type III in 24 (12%) and type IV in 18 (9%) patients. The association of age (P = 0.141) and gender (P = 0.345) with frontal sinusitis was not significant. The statistical association between type of frontal recess and frontal sinusitis was statistically not significant. The association between age and the type of frontal recess was found to be statistically significant by Fischer's exact test with P value of 0.012 (< 0.05), whereas gender was not associated with the type of frontal recess by the same test. It is difficult to overstate the significance of the terms frontal recess, frontal sinusitis, and sinus ostium in this particular medical context. This article was a retrospective observational study that investigates the connection between frontal sinusitis and changes in the frontal recess in patients receiving care at tertiary medical facilities.

Long-Term Follow-Up of Post Radiation Complete Sinus Opacification in Sinonasal Cancer Patients

OBJECTIVE

Treatment of sinonasal malignancies most often requires primary or postoperative radiation treatment. Post radiation sinonasal morbidity has been previously described; however, none addressed post-radiation sinus obstruction. Our objective was to investigate the long-term outcomes of post radiation complete isolated sinus opacification (CISO).

METHODS

A retrospective analysis of sinonasal cancer patients treated with radiation therapy during the years 2002 to 2022. Clinical, imaging and treatment data were collected from patients' medical records. Only patients with at least 12 months of follow-up and available imaging for review were included.

RESULTS

Out of 109 patients, 37 patients were identified to meet the inclusion criteria. Mean follow-up was 58 months. 35% of patients were diagnosed with persistent post radiation CISO with a mean onset of 4 months. All these patients remained asymptomatic, and their imaging remained stable during follow-up with none developing an expanding mucocele. Ethmoid sinus tumor involvement was found to be more prevalent in the CISO group (62% vs. 25%, p-value = 0.048) as well as chemotherapy/immunotherapy (54% vs. 38%, p-value = 0.046). Multivariant analysis revealed that ethmoid sinus involvement (OR = 9.516, p-value = 0.047) and adjuvant therapy, either chemotherapy/immunotherapy (OR = 10.75, p-value = 0.036) were found to be a predictive factor for complete opacification.

CONCLUSION

Our study revealed that a substantial number of post-radiation patients develop a stable and persistent CISO, often in the frontal and sphenoid sinuses. These patients remained asymptomatic, and none required surgical intervention during nearly 5 years of follow-up.

LEVEL OF EVIDENCE

4 Laryngoscope, 2024.

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.

Chitogel with deferiprone following endoscopic sinus surgery: improved wound healing and microbiome

Background

Adhesion formation, sinus ostial narrowing, and presence of pathogenic bacteria are associated with poor outcomes following endoscopic sinus surgery (ESS) for chronic rhinosinusitis. Chitogel has been shown to improve wound healing, restore a healthier microbiome, and reduce post-operative infections post ESS. Deferiprone has antibacterial properties and has been shown to reduce adhesion formation. The aim of the study was to assess whether the addition of low concentration deferiprone to Chitogel further improves surgical outcomes following ESS compared with Chitogel alone.

Methods

In this double-blinded trial, 45 patients undergoing ESS were prospectively recruited. At the end of the surgery, patients were randomised to receive Chitogel alone, Chitogel with 1 mM of deferiprone, or Chitogel with 5 mM of deferiprone to one side of the sinuses (allowing the other side to serve as control). Patients underwent routine follow-ups with symptom questionnaires and nasoendoscopies performed at 2, 6, and 12 weeks post-operatively. Sinus ostial measurements, microbiology, and microbiome swabs from bilateral middle meatuses were collected intraoperatively and at 12 weeks post-operatively.

Results

A significant improvement in the endoscopic appearance of the sinuses and frontal ostial patency was noted at 12 weeks post-operatively (p < 0.05) in all three treatment groups compared with the control. There was no significant difference noted between patients who received Chitogel alone and those who received Chitogel with 1 or 5 mM deferiprone.

Conclusion

Chitogel alone, Chitogel with 1 mM deferiprone, and Chitogel with 5 mM deferiprone used following ESS led to a significant improvement in endoscopic appearance of the sinuses and frontal ostial preservation at 12 weeks post-operatively. No significant difference was found with the addition of deferiprone to Chitogel.

[Local flap reconstruction techniques after frontal sinus drainage type II and III according to Draf]

BACKGROUND

Extended endonasal endoscopic frontal sinus surgery is characterized by bone resection beyond the lamellae of the frontal sinus and is currently classified according to Draf as type IIa, type IIb, modified type III (also referred to as type IIc), and type III. This approach is indicated when the surgical goal cannot be achieved through complete removal of the anterior ethmoidal cells. Numerous studies indicate restenosis rates ranging from 7 to 36%, despite creation of maximal openings. Exposed bone, which tends to epithelize slowly with significant crusting and the risk of uncontrolled wound healing depending on the local environment and other factors, is considered a contributing factor. Covering the exposed bone with mucosa can significantly reduce the risk of restenosis.

METHODS AND RESULTS

A variety of flap techniques for frontal sinus drainage in Draf III procedures are presented, including some variants that were part of presentations at the 2023 Congress of the European Rhinologic Society in Sofia, Bulgaria. These include combinations of free mucosal grafts, pedicled mucosal flaps, and hybrids combining both techniques. Additionally, the results of current studies are presented.

CONCLUSION

The results and achieved opening areas in contemporary Draf III surgeries are significantly improved and larger compared to the early stages of these procedures. A multitude of published studies consistently demonstrate that outcomes are markedly improved with mucosal coverage. Depending on the prevailing anatomy, mucosal conditions, and the extent of the surgical intervention, the most suitable technique should be selected. Therefore, proficiency in various methods is crucial. The use of a flap technique (free, pedicled, or combinations thereof) should be defined as the standard when performing extended frontal sinus surgery (Draf IIb, IIc, III, or endonasal frontal sinus surgery [EFSS] 4-6).

A Prospective Study on the Anatomical Variations of the Frontal Recess and its Association with Computer Tomographic Signs of Sinusitis

The frontal recess region has a complex anatomy and HRCT scans of the paranasal sinuses (PNS) are the gold standard in evaluating it. Classification systems have been established to identify the frontal recess cells. The objectives of this study are to describe the incidence of anatomical variations, classify the anatomy of the frontal recess using the IFAC & Kuhn's classification systems, find the association between the anatomical variations and the incidence of CT signs of sinusitis. A prospective study of patients undergoing HRCT-PNS was carried out. The frontal recess region was evaluated and classified as per both classification systems. The prevalence of each frontal cell was identified; presence of CT signs of sinusitis was noted and the correlation between the two was evaluated. 272 sides of HRCT scans were evaluated. Prevalence of cells as per IFAC classification showed ANC - 98.2%, SAC-43.4%, SBC-33.1%, SAFC- 28.3%, FSC -25%, SBFC- 3.7% and SOEC- 2.2%. Prevalence of cells as per Kuhn's classification showed ANC - 98.2%, Type 1- 38.2%, SBC-32.7%, FSC -24.3%, Type 3- 16.9%, Type 2- 12.9%, Type 4- 4.8%, FBC- 2.6% and SOEC-2.2%. Sinusitis was seen in 27.2% cases. A significant association was noted between the presence of SOEC, FSC and sinusitis as per both classification systems. (P=0.049 and P<0.001 respectively). In conclusion the cells which lead to an anteriorly based drainage pathway are more common, but the presence of posteriorly based SOEC and medially based FSC have a higher association with sinusitis.

["Radical" versus "functional" surgery of the paranasal sinuses-A contradiction?]

BACKGROUND AND OBJECTIVE

The terms "functional" and "radical" paranasal sinus surgery were often considered to be different operations which were mutually exclusive. This overview aims to look at the basics of these terms and surgical procedures and to work out the resulting surgical concepts for clinically relevant indications.

MATERIAL AND METHODS

Selective literature analysis using the data base PubMed, corresponding textbooks and resulting secondary literature regarding functional and radical or extended paranasal sinus surgery. Similarly, the current literature regarding clinically relevant indications for sinus surgery were analyzed.

RESULTS AND CONCLUSION

Modern pathophysiological knowledge, anatomically and pathophysiologically substantiated endoscopic surgical procedures and the usage of up to date technical possibilities have resulted in concepts which combine functional and so-called radical or extended surgery of the paranasal sinuses that complement each other and sometimes even overlap. The preoperative diagnosis and definition of underlying diseases are decisive and should be as precise as possible, as the extent and surgical details mainly depend on them: a sole creation of free drainage pathways, an additional creation of anatomical access for subsequent topical treatment or a complete (radical) removal of a pathological process.

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.

Anatomy of the Frontal Sinus Drainage Pathway Evaluated in 247 Cadavers to Prevent Cerebrospinal Fluid Leakage After Frontobasal Craniotomy

BACKGROUND AND OBJECTIVES

The frontal sinus (FS) drainage pathway (FSDP) may be a conduit for cerebrospinal fluid leakage after frontobasal craniotomy. In this cadaveric study, we aimed to evaluate the anatomy of the FSDP.

METHODS

The FSs and FSDPs of 247 cadavers were investigated. We counted the number of FSs and FSDPs in each half-head, verified the presence of a narrowing section in each FSDP, and evaluated the depth, shape, and size of each narrowing FSDP section.

RESULTS

We investigated 494 sides and 472 FSDPs of 247 cadavers. FSs were unilaterally undeveloped in 13 of 247 cadavers (5.3%) and bilaterally in 8 (3.2%). FSs were unilaterally duplicated in 7 of 247 cadavers (2.8%), and no FSs were bilaterally duplicated or triplicated. No FSs had 2 or more FSDPs, and all 472 investigated FSDPs were invariably narrowed at various depths. The narrowing FSDP sections were elliptical (78.6%), circular (18.1%), triangular (1.8%), or crescent-shaped (1.4%) and of varying thickness and orientation. Although FSDPs were asymmetric in 92.2% of cadavers and narrowing FSDP sections were located deep (8.9 ± 4.4 mm from the anterior skull base), the narrowing FSDP sections were typically small (area: 5.9 ± 3.3 mm 2 ) or thin (short diameter: 2.1 ± 0.7 mm).

CONCLUSION

Each FS had only one FSDP, all FSDPs were invariably narrowed at various depths, and the narrowing FSDP sections were sufficiently small or thin to allow local closure, facilitating prevention of cerebrospinal fluid leakage after frontobasal craniotomy.

Necessary Factors for Efficient Frontal Sinus Irrigation After Endoscopic Sinus Surgery: A Systematic Review

OBJECTIVE

The frontal sinus remains a challenging site for irrigation due to its position relative to the nostril and ethmoid sinus. This study aims to summarize the necessary factors for efficient irrigation of the frontal sinus after endoscopic sinus surgery (ESS) among patients with chronic rhinosinusitis (CRS).

METHODS

Using Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, a systematic literature review was conducted on PubMed, Scopus, and Cochrane databases to identify studies assessing the effect of frontal sinus irrigation in patients with CRS, cadaver models, or 3D-printed models of the sinonasal cavity after ESS.

RESULTS

Of the initial 206 abstracts reviewed, 18 full-text articles were included. The degree of the frontal sinus ostium opening after ESS was found to be associated with the efficacy of frontal sinus irrigation. More extensive frontal sinus surgeries tended to increase frontal sinus penetration. A Draf IIA procedure was identified as the minimum standard to achieve sufficient irrigation in the frontal sinus. Due to decreased backpressure in the nasal passage, increasing septectomy in Draf III did not significantly improve irrigation delivery. Squeeze bottles achieved significantly higher irrigation flow in the frontal sinus than syringes and pulsating devices. Large-volume irrigation devices provided better irrigation for the frontal sinus by entering or flushing the entire frontal sinus. The head position influenced the frontal sinus irrigation by altering the ostia position relative to fluid flow and vertical height of the frontal sinus during irrigation. While the vertex down head position was likely to enhance frontal sinus irrigation, the comfort of the head position and patient compliance should be considered.

CONCLUSION

Elements for optimization of frontal sinus irrigation are a minimum of a Draf IlA procedure for frontal sinus dissection, use of large-volume irrigation, and vertex down head positioning. Developing comfortable head positions with high frontal sinus irrigation efficiency would increase patient compliance and improve outcomes.

LEVEL OF EVIDENCE

NA.

Recreating the microscopic direct access Draf 2a frontal sinusotomy in the endoscopic era and comparison to an angled instrument approach

PURPOSE

Microscopic Draf 2a frontal sinusotomy relied on direct access. However, the modern-day endoscopic approach is hindered by the anterior-posterior dimensions of the frontal recess. The nasofrontal beak, angled endoscopes, and variable frontal recess anatomy make the surgery challenging. Carolyn's window frontal sinusotomy removes the limitation of anterior-posterior dimensions and is an endoscopic version of the microscopic Draf 2a. This study aims to compare the perioperative outcomes and morbidity from endoscopic direct access Draf 2a compared to angled access Draf 2a.

METHODS

Consecutive adult patients (> 18 years) seen at a tertiary referral clinic who underwent Draf 2a frontal sinus surgery using either endoscopic direct access (Carolyn's window) or endoscopic angled instrumentation were included. Patients who underwent Carolyn's window were compared to those with angled Draf 2a frontal sinusotomy.

RESULTS

One hundred patients (age 51.96 ± 15.85 years, 48.0% female, follow-up 60.75 ± 17.34 months) were included. 44% of patients used Carolyn's window approach. 100% [95% CI 98.2-100%] of patients achieved successful frontal sinus patency. Both groups were comparable for early morbidities (bleeding, pain, crusting, and adhesions) and late morbidities (retained frontal recess partitions). There were no other morbidities in the early and late postoperative periods.

CONCLUSION

The endoscopic direct access Draf 2a, or Carolyn's window, removes the anteroposterior diameter limitation. The frontal sinus patency and early and late surgical morbidities of direct access Draf 2a were comparable with the angled Draf 2a frontal sinusotomy. Surgical modifications, often with drills and bone removal, can be successfully made to enhance access in endoscopic sinus surgery without concern for additional morbidity.

Treatment Outcomes With Conservative Management of Frontal Sinus Outflow Tract Fractures

OBJECTIVE

Historically, early surgical management of frontal sinus outflow tract (FSOT) fractures has been standard practice. There has been a paradigm shift toward nonsurgical or delayed management. Unfortunately, clinical indications and treatment outcomes for this approach are poorly understood. This study evaluates radiologic indicators, as well as sinus reaeration and complication rates for FSOT injuries treated nonsurgically.

STUDY DESIGN

A retrospective cohort study of FSOT injuries between 2005 and 2019.

SETTING

Academic, tertiary care medical center.

METHODS

Radiographic fracture patterns of the frontal ostia (FO) and frontal recess (FR) were recorded as either patent, disrupted, or obstructed. Sinus reaeration, surgical rescue, and complication rates were documented. Patients with follow-up imaging >42 days were included. Patients undergoing immediate surgical intervention were excluded.

RESULTS

One hundred patients were identified and 44 met the criteria (88 sinuses). Among nonobstructed FSOT injuries (ie, patent or disrupted), reaeration occurred in 91% of the FO and 98% of FR injuries. Two sinuses required surgical rescue including 1 Draf IIB (1%), and 1 obliteration (1%). Two sinuses had complications including 1 mucocele (1%) and 1 cerebrospinal fluid leak (1%). FO and FR fracture patterns had no identifiable correlation with long-term reaeration rates or the need for surgical intervention.

CONCLUSION

Among nonobstructive injuries to the FSOT, average reaeration rates in observed patients were high (91%-98%). Rescue surgery (2%) and complication rates (2%) were low, suggesting that nonsurgical management of nonobstructed FSOT is a viable strategy. No radiographic features were clearly identified to be predictive of sinus reaeration.

Pneumatized Nasal Septum Extending to the Left Frontal Sinus "Septo-Frontal Cell": A Case Report

Multiple anatomical variations in the nasal cavity are well-described in the literature. We describe a rare case of pneumatization of the frontal sinus in the nasal septum that we term "Septo-Frontal Cell". To the best of our knowledge, this pattern of nasal septum pneumatization has not been described in the literature before. We have discussed the clinical and radiological findings and management of this patient.

Radiopathologic predictors of 1- and 2-year frontal sinusotomy outcomes in a southeast Asian chronic rhinosinusitis population

BACKGROUND

The frontal sinus and its drainage pathway are difficult spaces to navigate surgically. The complexity of the frontal recess anatomy as well as inflammatory factors may influence outcomes of endoscopic frontal sinusotomy. It is not clear which factors are more important in determining post-operative frontal ostium patency.

OBJECTIVE

The objective is to investigate whether the distribution of fronto-ethmoidal cells, frontal recess dimensions and sinonasal inflammation predict frontal ostium patency at 1- and 2-years after endoscopic frontal sinusotomy.

METHODS

A retrospective review of 94 chronic rhinosinusitis patients (185 sides) who had undergone endoscopic frontal sinusotomies between 2015 and 2019 was conducted. Computed tomography was used to evaluate the type of fronto-ethmoidal cells present and determine the dimensions of the frontal recess. The International Classification of the Radiological Complexity of frontal recess and frontal sinus was used to grade the complexity of frontal recess anatomy. Mucosal inflammation was graded according to a structured histopathology report. Frontal ostium patency at 1- and 2-years post-operatively was recorded.

RESULTS

The frontal ostium patency rates were 80.9% and 73.4% at 1- and 2-years respectively. Eosinophilic predominance (adjusted OR 3.5, 95% CI 1.6-8.0, p = 0.003) and mucosal ulceration on histology (adjusted OR 4.5, 95% CI 1.1-17.9, p = 0.033) predicted ostial stenosis at 1 year. Smoking (adjusted OR 7.6, 95% CI 2.4-24.7, p = 0.001), aspirin exacerbated respiratory disease (AERD) (adjusted OR 7.6, 95% CI 1.9-30.1, p = 0.004) and histological findings of severe inflammation (adjusted OR 8.9, 95% CI 1.9-41.2, p = 0.005) were independent predictors of ostial stenosis at 2 years. Frontal cell patterns, frontal recess dimensions and frontal recess complexity did not predict frontal ostium stenosis at both 1- and 2-years post-operatively.

CONCLUSION

Post-operative control of sinonasal inflammation is important in maintaining frontal ostium patency, regardless of frontal cell patterns or frontal recess dimensions.

International Frontal Sinus Anatomy Classification (IFAC): evaluation of frontoethmoidal cells prevalence in a Brazilian population

OBJECTIVES

The aim of this study was to evaluate the prevalence of the frontal cell variants according to International Frontal Sinus Anatomy Classification (IFAC), in the population of a Brazilian tertiary hospital, and analyze the reliability of the classification between observers.

METHODS

A cross-sectional study in the Hospital de Clínicas of the State University of Campinas, Brazil. One hundred and three Computed Tomography's (CTs) were evaluated by radiologists and otorhinolaryngologist to estimate the prevalence of frontoethmoidal cells according to the IFAC. Intraclass Correlation Coefficient (ICC) among examinators was used to evaluate reliability of this findings.

RESULTS

103 CT scans, totaling 206 sides, were evaluated independently. The agger nasi cell was the most prevalent, present in 95.63% of cases, 37.86% of the exams contained supra agger cells, frontal supra agger cell showed prevalence 37.37%; suprabular cell was present in 77.18% of the sides. As for the frontal suprabular cell, the prevalence was 30.09%, the supraorbital ethmoid cell was present in 32.03%, and frontal septal cell had a 33.49% prevalence. The ICC among the evaluators was classified as "good reliability" or "excellent reliability" for all cells.

CONCLUSION

This study describes the frontal cell prevalence among a population in tertiary Brazilian hospital, using the IFAC. This classification had a high ICC.

LEVEL OF EVIDENCE

Level 2: Individual cross-sectional study with consistently applied reference standard and blinding.

Frontal trans-sinusal approach: how I do it

BACKGROUND

Anterior skull base lesions could be reached by different approaches (subfrontal, pterional, interhemispheric, etc.). In selected cases, the frontal trans-sinusal approach is an effective alternative to conventional techniques.

METHODS

We present our technique to perform a frontal trans-sinusal approach in a patient affected by a large olfactory groove meningioma.

DISCUSSION-CONCLUSION

The frontal trans-sinusal approach allows to approach safely lesions of the median anterior cranial fossa. This approach provides lower brain retraction, easier access to olfactory grooves, and earlier tumor devascularization. However, it remains limited to patients with large-sized frontal sinuses and entails some postoperative risks such as mucocele or CSF leak.

Change of frontal sinus in age of according to the international frontal sinus anatomy classification

BACKGROUND

The radiological and surgical anatomy of the frontal sinus should be well-known in all age groups to successfully manage frontal sinus diseases and reduce the risk of complications in sinus surgery.

PURPOSE

To define frontal sinus and frontal cells according to the International Frontal Sinus Anatomy Classification (IFAC) criteria in pediatrics and adults.

MATERIAL AND METHODS

A total of 320 frontal recess regions of 160 individuals (80 pediatric, 80 adults) who underwent a computed tomography (CT) scan of the paranasal sinus (PNS) were included in the study. Agger nasi cells, supra agger cells, supra agger frontal cells, suprabullar cells, suprabullar frontal cells, supraorbital ethmoid cells, and frontal septal cells were evaluated in the CT analysis.

RESULTS

The incidence rates of the investigated cells were determined to be 93.1%, 41.9%, 60.0%, 76.3%, 58.5%, 18.8%, and 0% in the pediatric group, respectively, and 86.3%, 35.0%, 44.4%, 54.4%, 46.9%, 19.4%, and 3.4% in the adult group, respectively. Considering the unilateral and bilateral incidence of the cells, agger nasi cells were highly observed bilaterally in both the pediatric group (89.87%) and the adult group (86.48%).

CONCLUSION

Our study results show that IFAC can be used as a guide to increase the chance of surgical treatment in the pediatric and adult groups and that the prevalence of frontal cells can be determined radiologically and contributes to the generation of estimations of the prevalence of frontal cells.

Frontal Sinus Anatomy Variations in Race and Sex Using the International Frontal Sinus Anatomy Classification

Objective: To identify frontal sinus anatomical variations grouped by patient sex, race, and presence of chronic rhinosinusitis with frontal sinus involvement (CRFS) using the International Frontal Sinus Anatomy Classification (IFAC) system. Methods: A retrospective review from 2015 to 2020 was performed of consecutive adult patients with computed tomography sinus imaging. Prevalence of frontal sinus cells using the IFAC system was recorded. Comparisons were made between patient race, sex, and CRFS groups. Results: A total of 184 patients (368 sides) were included, 90 (48.9%) of which had CRFS. The racial distribution was 50 white (27.2%), 50 black (27.2%), 45 Hispanic/Latino (24.5%), and 39 Asian (21.2%) patients. The supra agger cell was most prevalent in the white population (P = 0.009), and supraorbital ethmoid cells were more prevalent in the Asian population (P = 0.017). Patients with frontal sinus disease were more likely to have a supraorbital ethmoid cell (P = 0.024). Overall, CRFS was more prevalent in the Asian population (P = 0.013). Conclusion: Significant differences in frontal sinus anatomy and disease exist between patient race and sex. Supraorbital ethmoid cells are associated with the development of CRFS. These patterns in frontal sinus anatomy should be noted prior to frontal sinus surgery to improve surgical awareness and outcomes.

Normal and Variant Sinonasal Anatomy

The anatomy of the paranasal sinuses is complex with multiple anatomic variants that can predispose patients to disease. Knowledge of this complex anatomy is important not only for successful treatment but to also avoid complications at the time of surgery. This article will review the anatomy with emphasis on a variety of clinically important anatomic variants.

The Frontal Sinus Drainage in Relation to Frontal Sinus Surgery

In order to perform a successful endoscopic frontal sinus surgery, prevent complications, and lower the recurrence risk, it is essential to understand the anatomy of the frontal sinus (FS) and frontal recess cells with many variations in frontal sinus drainage (FSD). Preoperative assessment of the FSD in three levels in order to find prognostic factors in the decision process regarding the kind and the extent of surgery when required. Three FSD levels were assessed by computed tomography in two dimensions; antero-posteriorly and laterally in 100 consecutive patients with chronic sinusitis symptoms. The first level represents the proper drainage of FS. The second level is the drainage of FS without the effect of the frontoethmoidal cells. The third level is the maximum drainage that can be achieved in a single FS. The relation of FSD levels to FS and frontoethmoidal cells pathology were assisted. Within 100 patients (200 sides, 186 FSs), for the proper FSD, antero-posterior (AP) length was 5.94 ± 3.42 mm in opaque FS and 5.32 ± 2.87 mm in clear FS and its lateral length was 3.04 ± 1.6 mm in opaque FS and 2.30 ± 1.25 mm in clear FS. For the functional FSD, AP length was 8.97 ± 2.7 mm in opaque FS and 8.05 ± 2.7 mm in clear FS and its lateral length was 7.51 ± 1.69 mm in opaque FS and 7.58 ± 1.75 mm in clear FS. In the anatomical FSD, AP length was 11.25 ± 3.07 mm in opaque FS and 10.01 ± 2.87 mm in clear FS and its lateral length was 11.1 ± 2.6 mm in opaque FS and 10.95 ± 1.7 mm in clear FS. This study offers essential data for preoperative assessment in order to improve surgeons' awareness of the frontoethmoidal region for optimal safe EFSS with lower incidence of complications and recurrences.

Anatomical landmarks for localisation of the anterior ethmoidal artery: a combined radiological and cadaveric (endoscopic) study

PURPOSE

The anterior ethmoidal artery is a major surgical landmark that is susceptible to iatrogenic injury during surgery of the anterior ethmoidal sinus, frontal sinus, and skull base. The present study aimed to define the location of the anterior ethmoidal artery in relation to specific anatomical landmarks using radiological imaging and endoscopic dissection.

METHODS

Eighty-six anterior ethmoidal arteries were assessed using computed tomography scans (bilateral analyses) and forty anterior ethmoidal arteries were assessed using cadaveric specimens (bilateral analyses). The skull base, anterior nasal spine, anterior axilla of the middle turbinate, and nasal axilla were morphometrically analysed to determine their reliability as anterior ethmoidal artery landmarks.

RESULTS

Distances to the skull base, anterior nasal spine, and nasal axilla displayed statistically significant differences between sexes and sides (p < 0.05). All landmarks demonstrated excellent reliability as anatomical landmarks for the localisation of the anterior ethmoidal artery, radiologically and endoscopically (ICC values ranged from 0.94 to 0.99).

CONCLUSION

The middle turbinate axilla was the most reliable landmark, due to the lack of statistically significant differences according to sex and laterality, and the high inter-rater agreement between measurements. Anatomical knowledge of variations and relationships observed in the present study can be applied to surgeries of the anterior ethmoidal sinus, frontal sinus, and skull base to improve localisation of the anterior ethmoidal artery, preoperatively and intraoperatively, and avoid iatrogenic injury of the vessel.

Anatomic misconceptions regarding the agger nasi cell: A preliminary analysis utilizing endoscopic anatomic dissection and three-dimensional computed tomography

The agger nasi cell is a key anatomic landmark in endoscopic frontal sinus surgery. However, discord amongst authors regarding anatomic definition and prevalence raises questions of its suitability as a surgical landmark. The purpose of this investigation is to evaluate the agger nasi cell using radiographic imaging correlated with endoscopic anatomic dissection to consider the cell's role as a surgical landmark and to explore if three-dimensional computed tomography (3D-CT) technology can provide enhanced insight into this anatomy. CT scans of 11 cadaveric sinonasal complexes were studied using triplanar CT or 3D-CT scanning with stereoscopic 3D imaging. Endoscopic dissections were performed and video recorded. Attention was given to identify agger nasi pneumatization and its origin. Pneumatization of the agger nasi region was noted in 4/11 cases (36.4%) (in two cases the pneumatization arose from the frontal recess, in two from a true agger nasi cell). The agger nasi region appeared as solid unpneumatized bone in 4/11 cases (36.4%). In 3/11 cases (27.3%) limited pneumatization was noted, bordering on but not pneumatizing the agger nasi proper. It may be confusing for otolaryngologic surgeons in training to rely on the "agger nasi cell" as a surgical landmark due to misconceptions regarding the anatomy, prevalence and anatomic definitions. Using standard CT scans to teach anatomy may have shortcomings as compared to the gold standard of surgical dissection. However, new 3D-CT holds promise to more accurately reflect small microanatomic features and provide an improved road map of a patient's anatomy in surgery.

Comprehensive access strategies to the frontal sinus

PURPOSE OF REVIEW

Despite the impressive evolutions in endoscopic endonasal approaches and instrumentations, the frontal sinus remains a challenging area. Different surgical options have been described over the years, but the main criticism lies in choosing the most suitable approach for a given case, based on the anatomy of each patient and the disease to treat. The purpose of this study is to provide a comprehensive review of surgical access strategies currently available to address the frontal sinus, including both endonasal and traditional external procedures, analysing indications, contraindications, complications and outcomes.

RECENT FINDINGS

Frontal sinus surgery includes minimally invasive endonasal approaches (balloon dilatation, Draf type I); extended endonasal approaches (Draf type IIA-IIB-IIC, Draf type III and their modifications via orbital transposition and contralateral pyriform aperture resection); external procedures (superior eyelid incision, frontal osteoplastic flap, Riedel procedure, Riedel-Mosher operation); and combined approaches.

SUMMARY

Recent advances in endoscopic endonasal techniques have deeply reshaped the surgical options to manage frontal sinus diseases, in an attempt to minimize the invasiveness of the procedures and maximize their outcomes. Traditional external procedures should be used in selected cases nonamenable for endonasal surgery. The appropriate selection of cases appears to be of paramount importance to obtain successful outcomes.

Computed tomography analysis of the anterior ethmoid genu of the frontal recess in non-diseased sinuses

OBJECTIVE

Knowledge of anatomical variations of the frontal recess and frontal sinus and recognition of endoscopic landmarks are vital for safe and effective endoscopic sinus surgery. This study revisited an anatomical landmark in the frontal recess that could serve as a guide to the frontal sinus.

METHOD

Prevalence of the anterior ethmoid genu, its morphology and its relationship with the frontal sinus drainage pathway was assessed. Computed tomography scans with multiplanar reconstruction were used to study non-diseased sinonasal complexes.

RESULTS

The anterior ethmoidal genu was present in all 102 anatomical sides studied, independent of age, gender and race. Its position was within the frontal sinus drainage pathway, and the drainage pathway was medial to it in 98 of 102 cases. The anterior ethmoidal genu sometimes extended laterally and formed a recess bounded by the lamina papyracea laterally, by the uncinate process anteriorly and by the bulla ethmoidalis posteriorly. Distance of the anterior ethmoidal genu to frontal ostia can be determined by the height of the posterior wall of the agger nasi cell rather than its volume or other dimensions.

CONCLUSION

This study confirmed that the anterior ethmoidal genu is a constant anatomical structure positioned within frontal sinus drainage pathway. The description of anterior ethmoidal genu found in this study explained the anatomical connection between the agger nasi cell, uncinate process and bulla ethmoidalis and its structural organisation.

Anterior ethmoid and frontal sinus drainage pathways: five patterns formed and defined by their bony walls

PURPOSE

To perform endoscopic sinus surgery safely and effectively, surgeons need to visualize the complex anatomy of the anterior ethmoid and frontal sinus region. Because this anatomy is so variable and individualized, the foundation of understanding lies in identifying, following, and visualizing the drainage pathway patterns and anticipating possible variations.

METHODS

We studied 100 sides (50 cases: 22 male, 28 female, aged 12-86, average age 46.5 years, ± 19.5) using computed tomography (CT) and multiplanar reconstruction (MPR) to identify and classify the drainage pathways leading to the frontal sinus and anterior ethmoidal cells.

RESULTS

Analysis revealed five patterns of drainage pathways defined by their bony walls: between the uncinate process and the lamina papyracea [UP-LP]; between the uncinate process and the middle turbinate [UP-MT]; between the uncinate process and the accessory uncinate process [UP-UPa]; between the uncinate process and the basal lamella of the ethmoidal bulla [UP-BLEB]; and between the basal lamella of the ethmoidal bulla and the basal lamella of the middle turbinate [BLEB-BLMT]. In most cases, BLEB formed the posterior wall of the drainage pathway of the frontal sinus, indicating BLEB could be one of the most important landmarks for approaching the frontal sinus.

CONCLUSIONS

As endoscopic sinus surgery depends on an understanding of this anatomy, this study may help surgeons to identify and follow the drainage pathways more accurately and safely through the anterior ethmoid to the frontal sinus.

[History of frontal sinus surgery and current view of the problem. Part 1]

Surgical treatment of inflammatory diseases of the frontal sinus is one of the biggest challenges of modern otorhinolaryngology. Close proximity of the frontal sinus and frontal sinus drainage pathways to the skull base, the orbit and the anterior ethmoid artery, great limitations with its visualization and instrumentation, and high risk of the frontal recess scarring cause difficulties in either endoscopic or external approaches to the frontal sinus. At the same time endoscopic approach to the frontal sinus is considered as preferred method of frontal sinusitis surgical treatment by majority of peers nowadays. The introduction of extended approaches to the frontal sinus pathology treatment with frontal sinus floor and interfrontal sinus septum drill-out as well as superior septectomy with common drainage pathway formation gave an opportunity to greatly decrease a rate of indications for external frontal sinus procedures. In this paper historical backgrounds of endonasal approaches to frontal sinuses are presented, current controversies in proper selection of extent and methods of the frontal sinus surgery are analyzed and endoscopic as well as external approaches to frontal sinuses are summarized.

Frontal Recess Cells in International Frontal Sinus Anatomy Classification (IFAC); Prevalence, Infection Incidence, and Relation to Frontal Sinus Infection in Chronic Sinusitis Patients

Frontal recess cells have many types with different sizes, arrangement, and extend. It plays an important role in successful functional endoscopic sinus surgery (FESS) as most causes of failure are related to it. Outline the prevalence of the frontal recess cells, pathological incidence of each cell regarding to frontal sinus pathology. Prospective study on 100 consecutive patients (200 sides) complaining from nasal and sinus symptoms which did not respond to medical management and indicated for FESS. Anterior group was infected in 30.8%; agger nasi cell (ANC) present in 97% (25.8% infected, 74.2% not infected), supra agger cell (SAC) present in 48% (39.6% infected, 60.4% not infected), supra agger frontal cell (SAFC) present in 11% (36.4% infected, 63.6% not infected). Posterior group was infected in 24.8%; supra bulla cell (SBC) present in 72% (30.6% infected, 69.4% not infected), supra bulla frontal cell (SBFC) present in 23% (17.4% infected, 82.6% not infected), supra orbital ethmoid cell (SOEC) present in 42% of cases (19% infected, 81% not infected). Medial group [frontal septal cell (FSC)] was present in 21% (33.3% infected, 66.7% not infected). FSC, SAC, SAFC, and SBC showed high infection rate in association with infected frontal sinus, while, the SOEC, ANC, and SBFC did not have such high infection rate. Frontal recess cells show no difference in their prevalence either if the frontal sinus infected or not, however their infection rate show significant difference.

Three-Dimensional Volumetric Analysis of Frontal Ethmoidal Cells and Evaluation of Influential Factors: A Helical Computed Tomography Study

In the present study, we aimed to assess frontal ethmoidal cells by using segmentation 3D software to establish a possible correlation between volume variation and both gender and age, as well as a relationship with Keros classification. Helical computed tomography images were obtained from 71 patients for analysis, in which the agger nasi cell, supra agger cell, supra agger frontal cell, supra bulla frontal cell, supraorbital ethmoidal cell, supra bulla cell, and frontal septal cell were identified and segmented to obtain their volume. Significant differences in volume were found for age and gender regarding agger nasi cells (p-value = 0.017), supra agger cells (p-value < 0.001), and frontal septal cells (p-value = 0.049). In the frontal septal cells, an increase of one year in age reduced the volume by 0.309, on average. According to Keros classification, the mean volumes were 10.07 and 25.64, respectively, for types II and III, both being greater than that of type I. Extracting volumetric data by using segmentation software in agger nasi cells, supra agger cells, and frontal septal cells may be useful for obtaining additional information related to age, in addition to possibly contributing to elucidating the anatomical variations in the region and an identification forensic tool.

[A case report of large supra bulla frontal cell infection and literature review]

Chronic sinusitis （CRS） is one of the most common nasal diseases, and FSDP is a risk factor for CRS. The variation of the frontal recess cell obstructs the frontal sinus drainage pathway, which makes the frontal sinus surgery more difficult and a higher recurrence rate than other sinus surgeries. Therefore, before surgery, a thin-slice CT scan is performed on the patient to fully evaluate the anatomical structure and drainage pathway of the frontal sinus, and to understand the variation of FSDP cell is crucial for accurate opening of the frontal sinus. In this paper, A case of large supra bulla frontal cell infection was summarized and analyzed. The anatomical structure of the frontal recess was fully understood by preoperative radiographs, the spatial relationship between the cells was identified, and the appropriate surgical plan was developed, which was beneficial for the surgeon to accurately open the frontal cortex during surgery and avoid postoperative recurrence.

The nasopharynx as a window to half a billion years of evolutionary change to the upper respiratory tract

The nasopharynx is a region at the nexus of several vital physiological systems, including the nasal cavity, oral cavity, braincase, middle ear, and cervical vertebrae. It has undergone pronounced morphological change over the course of tetrapod, mammalian, and human evolution. However, despite its place in evolutionary history, the nasopharynx has received relatively little attention. This special issue focuses on "the evolution, development, and functional morphology of the nasopharynx and its boundaries." Topics covered here include evolutionary developmental biology (or evo-devo), nasopharyngeal adaptions in bats, the importance of the nasopharynx and adjacent structures over the course of human evolution, normal development, middle ear morphology, clinical importance, and the study of the nasopharynx throughout history. Contributions to this special issue range among reviews and syntheses, descriptive analyses, phylogenetic analysis, traditional morphometrics, three-dimensional geometric morphometrics, and computational fluid dynamics. Here, we discuss the central importance of the nasopharynx as can be seen through vertebrate paleontology and comparative morphology. It is via the composite evolutionary history of the nasopharyngeal boundaries that our origins may be better understood, starting with the derivation of the choanae from the median olfactory pit of jawless fish nearly half a billion years ago to the basicranial flexion and facial reduction that distinguish Homo sapiens from all other living mammals. Indeed, the nasopharynx must be acknowledged for its importance in the processes of encephalization and acquisition of speech that have become the hallmark of our species.

The Draf III procedure: A review of indications and techniques

The Draf Ⅲ procedure involves the creation of a common frontal sinus cavity. The most common indication for the Draf Ⅲ procedure is chronic rhinosinusitis of the frontal sinuses despite the failure of more conservative interventions such as bilateral Draf Ⅱa procedures. Primary Draf Ⅲ may be indicated in patients with a high risk of failures such as those with severe polyposis and those with a frontal sinus opening less than 4 mm on computed tomography imaging. Other indications for the Draf Ⅲ include access for tumor removal and repair of traumatic fractures of the frontal sinus. The “inside‐out” Draf Ⅲ procedure is the standard approach when the frontal recess anterior–posterior diameter is wide enough for instrument access, usually larger than 4–5 mm. The “outside‐in” Draf Ⅲ procedure can be done when the frontal recess is too narrow to safely accommodate instruments. Regular follow‐up with debridement should be done to prevent neo‐ostium stenosis.

Three dimensional computer tomography analysis of frontal recess cells, difficulties in identification cells in patients witch diffuse primary chronic rhinosinusitis. The International Frontal Sinus Anatomy Classification (IFAC)

ABSTRACT BACKGROUND: The International Frontal Sinus Anatomy Classification (IFAC) is a consensus document created to standardize and specify the naming of cells within the region of the frontal recess and frontal sinus. The aim of this study was to analyze the difficulties in identifying cells according to the IFAC in patients with diffuse primary chronic rhinosinusitis. METHODS: Three independent reviewers examined triplanar computed tomography (CT) scans to assess the anatomy of the frontal recess using the IFAC system. CT scans were chosen randomly and divided into 3 groups: CT scans of patients not presenting sinus complaints (control group), CT scans of patients affected by diffuse primary chronic rhinosinusitis non-type 2, and CT scans of patients affected by diffuse primary chronic rhinosinusitis type 2. RESULTS: Identification of all frontal cell types was accurate in patients not presenting sinus complaints (p-value <0,05). Patients scoring 9 or more points in the Lund-Mackay scoring system demonstrated a statistically increase of risk of improper identification of frontal recess cells (p-value <0,0001). CONCLUSIONS: Due to the large number of possible anatomical variants and changes caused by the chronic inflammatory disease, the IFAC nomenclatura is easier to apply to non-type 2 primary diffuse CRS patients with low scores in the L-M scores scale than to primary diffuse type 2 CRS patients with higher M-L scores.

The Effects of Suprabullar Pneumatization on the Orientation of Its Surrounding Anatomical Structures Relevant to the Frontal Drainage Pathway

Objective: The aim of this study was to evaluate the effects of suprabullar pneumatization on the orientation of the frontal sinus outflow structures and its association with the volume of anterior ethmoid sinus. Methods: A retrospective chart review of computed tomography of paranasal sinuses (CTPNS) images was conducted. A total of 370 sides of the CTPNS of 185 patients were analyzed. Results: The course of anterior ethmoidal artery (AEA) along the skull base (p = 0.04) and position of AEA at the second lamella (p = 0.04) was significantly associated with the type of suprabullar pneumatization. The AEA is expected to be lower at the skull base and at a longer distance from the second lamella with the increase in grading of the suprabullar pneumatization. The distance of AEA to the second lamella (p < 0.001) and third lamella (p = 0.04) was significantly different depending on the type of suprabullar pneumatization, which indicates AEA is expected to be at a longer distance from the second lamella and third lamella in higher grade suprabullar pneumatization. The type of suprabullar pneumatization has a significant but weak association with the anterior ethmoid sinus volume (p = 0.04). Conclusions: There is a significant effect of the type of suprabullar pneumatization on the orientation of the surrounding anatomical structures at the frontal recess. The type of suprabullar pneumatization is influenced by the anterior ethmoid sinus volume, which suggests it has a possible role in the frontal drainage pathway.

Computed Tomography Analysis of the Anterosuperior Portion of the Bulla Lamella in Chinese Subjects and Its Surgical Significance in Endoscopic Frontal Sinusotomy

INTRODUCTION

The anterosuperior portion of the bulla lamella can extend into the frontal sinus and form the supra bulla frontal cell (SBFC) and supraorbital ethmoid cell (SOEC). This can affect the frontal drainage pathway and make surgery more challenging.

OBJECTIVES

The aim of the study was to compare the anatomical characteristics of SBFC and SOEC in Chinese chronic rhinosinusitis (CRS) patients and explore the relationship between the cells and frontal sinusitis (FS). The surgical skills in dealing with these cells were also studied.

METHODS

We prospectively identified SBFC and SOEC in 114 patients with CRS by computed tomography (CT). The sides of the patients were divided into groups A (with FS) and B (without FS). CT scans were analyzed to distinguish the SBFC, SOEC, and the drainage pathway. Statistical analysis was conducted to determine whether the cells were associated with the occurrence of FS.

RESULTS

The prevalence of frontal cells was as follows: SBFC: 9.65%, SOEC: 21.93%. There was an association between the presence of SBFC and FS (p < 0.05). The anterior drainage pathway was present in patients with SBFC and SOEC, anterolateral pathway in those with SBFC/SOEC coexisting with the frontal septal cell, and anteromedial pathway in those with SBFC/SOEC coexisting with the supra agger frontal cell.

CONCLUSIONS

There was an association between the presence of SBFC and the occurrence of FS. Extension of the anterosuperior portion of the bulla lamella into the frontal sinus obstructed the drainage pathway posteriorly. Understanding the anatomy may help surgeons thoroughly dissect the bulla lamella.

Comparison between the endoscopic scores of bolgerization versus partial resection of the middle turbinate for management of the postoperative lateralization in the early follow-up period after endoscopic frontal sinusotomy: A randomized controlled study

BACKGROUND

Frontal sinusotomy is a challenging procedure that needs meticulous handling due to its unique anatomical position. Postoperative middle turbinate lateralization is critical comorbidity for the success rate, and many techniques are adopted to prevent it. The study aimed to compare the effect of middle turbinate bolgerization and partial resection on the postoperative endoscopic scores and assess their impact on the middle meatus and the frontal recess outcome.

PATIENT AND METHODS

This prospective study was conducted on forty-one patients undergoing bilateral frontal sinusotomy for chronic frontal sinusitis. Nasal cavities were randomized so that partial middle turbinate resection technique was done alternately with bolgerization approach in every patient. Each participant acted as their control. Both sides were compared using Lund Kennedy Endoscopic Score (LKES) and Perioperative Sinus Endoscopy Score (POSE) at the baseline, 1st, 3rd, and 12th-month intervals postoperatively. Also, middle turbinate status was assessed at the end of the 12th-month interval using POSE score.

RESULTS

The total frontal sinus patency rate was 82.9% (63/76 operated sinus). Baseline scores, LKES (3.79 ± 0.777 vs 4.05 ± 0.769, p = 0.142, for the side of resection and the side for bolgerization respectively) and POSE (1.79 ± 0.413 vs 1.82 ± 0.393, p = 0.777, for the side of resection and the side for bolgerization respectively). Regarding LKES, the differences between both operated sides were fluctuating with p values: 0.001*, 0.171, and 0.044* for the 1st, 3rd, and 12th months follow-up intervals, respectively. Regarding the POSE score of the frontal sinus, the difference between both groups was steadily increasing with p values: 0.318, 0.119, and 0.017* for the 1st, 3rd^, and 12th months follow-up intervals. The middle turbinate's POSE score at the 12th month was significantly higher in the side allocated for bolgerization (p-value = 0.008*).

CONCLUSION

Partial middle turbinate resection showed favorable endoscopic outcomes than bolgerization at the 12th month follow up period in patients undergoing primary ESS for chronic frontal sinusitis.

N, Hosemann W. Supplements and refinements to current classifications and nomenclature of the fronto-ethmoidal transition region by systematic analysis with 3D CT microanatomy

Objective: The microanatomy of the fronto-ethmoidal transition region has been addressed in several classifications. CT stereoscopic imaging (3DCTSI) provides improved display and delineates three defined complex “spaces”, the Frontal Sinus/Frontal Recess Space, the Infundibular Space of the Ethmoid Uncinate Process, and the Ethmoid Bulla Space (FSRS, IS-EUP, EB), none of which were adequately described with the “cell” terminology. We present details on the 3D microanatomy, variability, and prevalence of these spaces. Methods: 3D stereoscopic imaging displays (3DCTSI) were created from 200 datasets. The images were analyzed and categorized by a radiologist (SJZ), and consultant otolaryngologists, focusing on 3D microanatomy of the fronto-ethmoidal transition, the frontal recess/frontal sinus, and drainage pathways, in comparison to established anatomical classification systems. Results: The anterior ethmoid is subdivided into seven groups with the following core properties and prevalence: 1. The horizontal roof of the IS-EUP is attached to the superior half of the frontal process of the maxilla (19%); 2. The IS-EUP extends into the frontal recess (6.5%); 3. The IS-EUP extends into the frontal recess and the frontal sinus (18.5%); 4. A bulla is seen in the medial frontal sinus (3%); 5. The ethmoid bulla and supra bullar space extend into the frontal sinus (7%); 6. Lamellae extend into the FSRS antero-superiorly (25%); 7. FSRS expansion expands below the upper half of the frontal process of the maxilla (FSRS) (21%). Conclusion: 3-D analysis of the detailed anatomy provides important new anatomic information with the increased focus on precision surgery in the region.

Frequency of the frontal sinus aplasia among Saudi Arabian population. A single-center retrospective case review

OBJECTIVES

To assess the frequency of frontal sinus aplasia using computed tomography (CT) of the paranasal sinus among Saudi Arabian population.

METHODS

A retrospective case review of medical records from January 2019 to December 2019 in the Otorhinolaryngology Department, King Abdulaziz University, Riyadh, Saudi Arabia.

RESULTS

A total of 449 cases were reviewed. The incidence of bilateral frontal sinus aplasia was 3.3%. The incidence of right sinus agenesis was 5.12% and left was 1.33%. The mean age of reviewed patients was 39.15 years.

CONCLUSION

The frequency of frontal sinus aplasia is low; however, this must be considered before surgical operations related to the sinuses.

Usefulness of endonasal mucoplasty in the surgical treatment of chronic rhinosinusitis with nasal polyps. Prospective study

Chronic Rhinosinusitis with Nasal Polyps (CRScPN) is a disease with great impact on health. The surgical option using endoscopic nasosinus surgery is the therapeutic alternative when control of the disease is not achieved with medical treatment. Extensive endoscopic approaches are being postulated as a possible best surgical treatment option in certain phenotypes of CRScPN. Endonasal mucoplasty associated with these approaches has been shown to be a complementary technique that improves both healing and mucosal oedema in patients with CRScPN in the short term. The aim of our study was to analyse the results of endonasal mucoplasty associated with a complete ethmoid-sphenoidotomy plus grade III frontal sinusotomy in the treatment of CRScPN in the medium term. For this purpose, a prospective case-control study (10/10) was carried out on patients with CRScPN. In the case group, endonasal mucoplasty in the left nostril was associated with surgery, and the control group was not. The assessment of quality of life at one year after surgery, as measured by the mean difference in SNOT-22 (mean [SD]), in the case group was significantly better than in the control group, (45.9 [19.6]-26.6 [16.05], P = 0.027). The endoscopic improvement in healing and mucosal oedema, measured by the Modified Lund-Kennedy scale, showed relevant improvements, when comparing both pits, but without reaching significance (P = 0.29). Endonasal mucoplasty promotes short-term healing, improving the quality of life in the medium term (one year) of patients treated with extensive endoscopic breast resections.

Frontal Sinus Fractures: A Review on Etiology and Management Emphasizing Minimally Invasive and Endoscopic Techniques

ABSTRACT

In spite of a long and tortuous history of the acute management of frontal sinus fractures, current optimal management remains steeped in controversy. These fractures are frequently produced by excessive forces and are often accompanied with other injuries. However, disruption of the nasofrontal duct persists as essential to maintain proper sinus function and should guide current management. Although there has never been any distinct procedure defining optimal outcomes, proper treatment is contingent on precise diagnosis culled from a complete history, physical examination, and imaging studies. This is further augmented by the surgeon's intraoperative findings. Reconstruction will ultimately rest on the degree of disruption of the anterior and posterior sinus walls, as well as the status and function of the nasofrontal ducts. For these reasons, current management continues to be challenging and evolving. Thus, this review will discuss the etiology and clinical presentation of frontal sinus fractures, the current complications arising in the subject, and the evolution of treatment options towards a more conservative and endoscopic approach to care.

The prevalence of frontal cell variants according to the International Frontal Sinus Anatomy Classification and their associations with frontal sinusitis

BACKGROUND

The International Frontal Sinus Anatomy Classification (IFAC) is introduced to simplify the classification of different frontal cell variants based on their topographical structures. The objectives of our study were to determine the prevalence of the frontal cell variants according to IFAC and their association with the development of frontal sinusitis.

METHODOLOGY

A retrospective chart review on computed tomography paranasal sinus (CTPNS) was conducted. A total of 200 patients who had clinical and endoscopic findings of chronic rhinosinusitis (CRS) and undergone CTPNS were reviewed. The CTPNS was evaluated for the presence of frontal cell variants according to IFAC and mucosal changes consistent with frontal sinus involvement.

RESULT

A total of 400 sides of the CTPNS were analyzed. The agger nasi cells (ANCs) were the most common (95.5%) followed by supra bulla cells (SBCs) (60.8%), supra bulla frontal cells (SBFCs) (53.0%), supra agger cells (SACs) (50.0%), supra agger frontal cells (SAFCs) (36.0%), frontal septal cells (FSCs) (8.3%), and supraorbital ethmoidal cells SOECs (5.5%). There was significant association between SOEC (p = 0.001) and FSC (p = 0.044) with the development of frontal sinusitis.

CONCLUSIONS

Apart from ANCs, the posterior-based cells (SBCs and SBFCs) have higher prevalence than the anterior-based cells (SACs and SAFCs). Despite being the least, both SOECs and FSCs are significantly associated with frontal sinusitis.

The prognostic variables affecting the frontal sinusotomy patency outcome and how to manage: A prospective study

OBJECTIVES

The study aimed to assess the factors affecting the frontal sinus patency after endoscopic frontal sinusotomy.

DESIGN

A prospective cohort study.

SETTING

Tertiary centre hospital.

MAIN OUTCOME MEASURES

Fifty patients with refractory chronic frontal sinusitis (83 operated frontal sinuses) had frontal sinusotomy and followed up for six months. Multiple operative factors were included the type of the procedure, intraoperative sinus findings, degree of mucosal preservation and middle turbinate stability. Other factors were also assessed, including smoking, the presence of allergic rhinitis, asthma, gastroesophageal reflux and other associated medical comorbidities.

RESULTS

The sinus patency success rate was 75.9%. There was a significant difference regarding the intraoperative anteroposterior sinus ostium diameter (5.36 ± 1.45 mm vs 8.88 ± 2.38 mm, P-value: .001* in the failed group and the success group, respectively). There was a significant association between the patency outcome and the presence of associated medical comorbidities (P-value: .001*), the presence of allergic rhinitis (P-value: .001*), the degree of sinus mucosal preservation (P-value: .012*) and the degree of middle turbinate stability (P-value: .001*). The multivariate analysis showed that the intraoperative anteroposterior diameter of the sinus ostium, middle turbinate stability and presence of allergic rhinitis were significant predictors (P-value: .012*, .042* and .013*, respectively).

CONCLUSION

Sinuses with anteroposterior ostium diameters less than 5.36 mm are more susceptible to restenosis. The flail middle turbinate increases the risk of postoperative middle meatus synechia and frontal sinus patency failure. The presence of allergic rhinitis has a negative impact on the patency outcome.