Maxillary Sinus Ostium Research Articles

Anatomical Variations Associated With Maxillary Sinus Fungal Ball.

We investigated the anatomical and dental factors associated with unilateral maxillary sinus fungal ball (MSFB). Also, we evaluated the effect of combinations of those factors on the incidence of MSFB. Three hundred patients were divided into MSFB, normal, and chronic rhinosinusitis (CRS) groups. We reviewed paranasal computed tomography scans for the presence of deviated nasal septum, concha bullosa (CB), Haller cells, and various dental factors. Also, we measured the ethmoid infundibulum, maxillary natural ostium, and CB. Maxillary sinus fungal ball showed a more significant association with CB compared to the other 2 groups (37%, P < .05). The MSFB group had a lower rate of Haller cells than the normal group (10% vs 22%, respectively; P < .05). Also, the MSFB group had a wider maxillary sinus ostium than the normal group (7.07 ± 1.8 vs 5.48 ± 1.3 mm; P < .01). Moreover, the combination of CB and Haller cells was significantly associated with a decreased rate of the fungal ball (P = .047, odds ratio = 0.694). The dental factors were more prevalent in the MSFB and CRS groups (73% and 75%, respectively) than in the normal group (32%, P < .001). Maxillary sinus fungal ball is significantly associated with CB, Haller cells, an increased maxillary sinus ostium size, and dental factors.

A Case of Endoscopic Reduction of Isolated Maxillary Sinus Posterior Wall Fracture Using Foley Catheter

The surgical goal for reduction of maxillofacial fracture has been focused on the reconstruction of facial buttresses. If there is fracture-displacement at non-buttress area, it close observation used to be the choice of treatment. It is not easy to have access to the posterior part of maxilla with conventional approach. But with the endoscopic sinus surgery technique, posterior wall of maxillary sinus is easily approachable and can be manipulated. This report presents a case of a 38-year-old male with isolated posterior wall of maxillary sinus fracture. Inward comminuted fracture-displacement of the posterior wall of maxillary sinus with retroantral fat and soft tissue was herniated into the maxillary sinus and extruded out through the natural ostium of maxillary sinus. Using endoscopic approach and Foley catheter inflation, the maxillary sinus posterior wall was successfully repaired without complications. This report thus suggests endoscopic approach with the Foley catheter for the posterior maxillary sinus wall fracture.

Ancestry-based variation in maxillary sinus anatomy: Implications for health disparities in sinonasal disease.

Paranasal sinus drainage is mediated by mucociliary transport and gravity. However, human orthograde posture, along with the superior positioning of the maxillary sinus (MS) ostium, increases reliance on the mucociliary system. Previous research has thus suggested that differences in MS size and shape may impede mucociliary clearance, potentially contributing to disparities in sinusitis susceptibility. To further investigate this hypothesis, this study collected 29 three-dimensional (3D) coordinate landmarks and seven linear measurements of MS morphology from 167 computed tomography (CT) scans of crania of European, East Asian, or Equatorial African ancestry. MANOVA results reveal the Asian-derived individuals are characterized by both a significantly taller MS (F=14.15, p < 0.0001) and a significantly greater distance from the MS floor to the ostium (F=17.22, p < 0.0001) compared to those of European and African ancestry. A canonical variate (CV) analysis conducted on 3D landmark data provides corroborative results, distinguishing Asian-derived individuals predominantly on the basis of a relatively lower MS floor. As a greater distance between the MS floor and ostium may impede mucociliary clearance, our results suggest MS anatomy may be a more prominent factor in chronic sinusitis among individuals of Asian ancestry compared to those of European and African ancestries. This provides tentative evidence of an anatomical etiology for chronic sinusitis even in the absence of anatomical variants/abnormalities (e.g., nasal polyps, concha bullosa, Haller's cells, and Agger nasi cells). Further research into the relationship between MS anatomy and sinusitis, in addition to socioeconomic inequalities of healthcare, is warranted to continue evaluating possible contributions to health disparities.

Method for Determining Maxillary Sinus Ostium for Cone-beam Computed Tomography Imaging

Method for Determining Maxillary Sinus Ostium for Cone-beam Computed Tomography Imaging

Evaluation of the Prevalence of Concha Bullosa in Cone-Beam Computed Tomography Images

Background: The ostiomeatal complex (OMC) is not a separate anatomical structure although it is a functional unit of structures, including the middle meatus, uncinate process, infundibulum, maxillary sinus ostium, ethmoidal bulla, anterior ethmoid sinus ostium, and frontal recess. Concha bullosa is the pneumatization of the concha, which is one of the most common anatomical variations in the middle turbinate. Methods: This study was conducted using the cone-beam computed tomography (CBCT) images of 172 patients in the archives of the Department of Oral and Maxillofacial Radiology, Dentistry School, Ahvaz Jundishapur. Patient information including age and gender, presence or absence of concha bullosa, the involved side (left or right), and its type (i.e., extensive, lamellar, and bulbous) were collected in the information form. Finally, the chi-square test (with SPSS, version 22) was used to analyze the data, and P value less than 0.05 was considered statistically significant. Results: Patients with and without concha bullosa were 39.1 and 41.7 years, respectively, but it was no significant difference in terms of age (P = 0.321). Out of 52 patients with concha bullosa, 19 (36.5%) cases were males and 33 (63.5%) of them were females. The prevalence of concha bullosa was higher for the bilateral side (20 patients, 38.5%, P = 0.000). The prevalence of bulbulsand lamellar-shape was nearly the same (32.7% and 30.8%, respectively). Eventually, the extensive shape with 36.5% was more frequent for the shape of concha bullosa (P = 0.000). Conclusions: The prevalence of concha bullosa was high. There was no significant difference in terms of age (P = 0.321) and gender (P = 0.058) of patients with concha bullosa. The extensive type and the bilateral appearance of concha bullosa were more significant (P = 0.000).

An Anatomic Study on the Maxillary Sinus Mucosal Thickness and the Distance between the Maxillary Sinus Ostium and Sinus Floor for the Maxillary Sinus Augmentation.

Background and objectives: The average rate of chronic sinusitis after maxillary implantation was approximately 5.1%. However, the evidence of predictive risk factors for sinusitis after implantation is lacking. The aim of this study was to perform an anatomic study on the maxillary sinus mucosal thickness (MSMT), the distance between the maxillary sinus ostium and sinus floor (MOD), and the MSMT/MOD ratio as a preoperative risk indicator for sinusitis after maxillary dental implantation. Materials and Methods: Between October 2008 and October 2019, all patients referred to the otolaryngology department were included in this study. A total of 120 patients were enrolled. The 95 patients who received no treatment prior to implantation were classified into Group A, the 16 patients who used antibiotics before implantation were classified into Group B, and the patients who had implants inserted after functional endoscopic sinus surgery were classified into Group C. The MSMT, MOD, MSMT/MOD ratio, anatomical factors associated with ostial obstruction, and the occurrence of postoperative sinusitis were reviewed. Results: There were significant group differences in MSMT (Group A vs. Group B, p = 0.001; Group B vs. Group C, p = 0.003; Group C vs. Group A, p < 0.0001). The MOD showed no significant difference among the three groups. The MSMT/MOD ratio showed significant differences between Groups A and B (p = 0.001), B and C (p < 0.0001), and C and A (p < 0.0001). Conclusions: It is important to check not only the proportion of the maxillary sinus occupying lesion, but also the status of the maxillary sinus osteomeatal complex when making therapeutic decisions. In addition, collaboration between dentists and otolaryngologists could improve outcomes in patients with maxillary sinus lesions.

Involvement of the maxillary sinus ostium (MSO) in the edematous processes after sinus floor augmentation: a cone-beam computed tomographic study

BackgroundAfter sinus floor augmentation, a thickening of the sinus mucosa has been described. The aim of the present study was to evaluate the involvement of the maxillary sinus ostium in the edematous processes after a sinus floor augmentation procedure.MethodsSeventy-two cone-beam computerized tomographies (CBSTs) were taken before sinus floor augmentation and after 1 week and 9 months from surgery and analyses. Sinus mucosa thickness and area, ostium diameter and patency, and extension of the post-surgical transient mucosal thickening in relation to the ostium were evaluated on the CBCTs for all three periods. The term “virtual” when referring to sinus mucosa thickness and area was introduced because of the edema and bleeding that both contributed to a transient thickening and additional elevation of the sinus mucosa.ResultsThe mean virtual thickness of the sinus mucosa was 2.7 ± 4.0 mm, 7.7 ± 7.1 mm, 1.7 ± 2.0 mm before surgery, and after 1 week and 9 months. The virtual mucosa area was 37.2 ± 52.5 mm2, 184.5 ± 153.8 mm2, and 34.0 ± 50.7 mm2. The ostium diameter at the three periods evaluated was 1.8 ± 0.5 mm, 1.1 ± 0.6 mm, 1.5 ± 0.8 mm, respectively. Three infundibula (4.2%) were found out of patency before surgery while this number increased to 14 (19.4%) after 1 week. Nine months after surgery, only one infundibulum (1.4%) was out of patency, however, without presenting signs of sinus pathologies. The extension of the mucosal edema on the palatal sinus was reduced after 9 months of healing.ConclusionsOne week after sinus floor augmentation, the maxillary sinus mucosa increased in dimensions and in several cases involved the ostium, reducing its diameter and producing a transient loss of patency. After 9 months of healing, the initial conditions were recovered.

Radicality of maxillary sinus surgery and size of the maxillary sinus ostium

Until the 1990s, radical sinus surgery was considered astandard procedure for maxillary sinus diseases, but it is no longer favored due to the high morbidity. Today, functional endoscopic sinus surgery (FESS) is considered the gold standard in sinus surgery. Modifications of surgical approaches also allow access to regions of the maxillary sinus that were previously difficult to reach. Depending on anatomy and pathology, different methods for widening the maxillary ostium can be selected. In typeI sinusotomy, the natural ostium is widened dorsally by amaximum of 1 cm. Sinusotomy typeII involves widening the natural ostium up to amaximum diameter of 2 cm. In sinusotomy typeIII, the natural ostium is widened dorsally to the posterior wall of the maxillary sinus and caudally to the base of the inferior turbinate. Beside the prelacrimal approach, more invasive approaches are the medial maxillectomy, in which the dorsal part of the inferior turbinate and the adjacent medial wall of the maxillary sinus is resected, as well as its modifications "mega antrostomy" and "extended maxillary antrostomy." Correct selection of the size of the maxillary sinus window is prerequisite for successful treatment and long-term postoperative success. Isolated purulent maxillary sinusitis can usually be treated by atypeI sinusotomy. Sinusotomy typeII addresses nasal polyps with involvement of the mucosa of the ostium, recurrent stenosis after previous surgery, chronic maxillary sinusitis due to cystic fibrosis, and purulent maxillary sinusitis with involvement of other adjacent sinuses. Sinusotomy typeIII is required for choanal polyps with attachment to the floor of the maxillary sinus, for extensive polyposis and fungal sinusitis, and for inverted papilloma. Particularly for (recurrent) disease and extensive interventions in the maxillary sinus, medial maxillectomy or a modification thereof may be required.

TRANSNASAL ENDOSCOPIC PRELACRIMAL RECESS APPROACH IN A SURGICAL TREATMENT OF ANTROCHOANAL POLYP

maxillary sinus, through the maxillary sinus ostium with extension into the choana. They represent approximately 4–6% of all nasal polyps in the general population. Antrochoanal polyps are almost always unilateral, although there are few cases of bilateral ACPs in the literature. Objective: To assess the effectiveness of endoscopic transnasal prelacrimal recess approach (ETPRA) in preventing the recurrence of antrochoanal polyps and evaluate the outcomes and possible complications of prelacrimal recess approach for treatment of antrochoanal polyps. Patient and Methods: forty patients with antrochoanal polyp underwent surgery with a transnasal endoscopic prelacrimal recess approach. The approach was evaluated for the ability to visualise the origin of the polyp in the maxillary cavity, complications and recurrence of the polyp. Results: Transnasal prelacrimal recess approach was successful in 80% of the patients (32/40), 80% of patients (32/40) did not encounter epiphora postoperatively, 85% of them (34/40) had no epistaxis, 90% of them (36/40) had no cheek edema. None of them had nasal obstruction, nasal stenosis or adhesions, All of them had the flap healed, and all of them had the inferior turbinate preserved. During the follow-up period (1 year) no recurrence had developed. Conclusion: Prelacrimal recess approach is a safe procedure which allows for complete removal of the antral part of the antrochoanal polyps to prevent recurrence without major complications.

TRANSNASAL ENDOSCOPIC PRELACRIMAL RECESS APPROACH IN A SURGICAL TREATMENT OF ANTROCHOANAL POLYP

maxillary sinus, through the maxillary sinus ostium with extension into the choana. They represent approximately 4–6% of all nasal polyps in the general population. Antrochoanal polyps are almost always unilateral, although there are few cases of bilateral ACPs in the literature. Objective: To assess the effectiveness of endoscopic transnasal prelacrimal recess approach (ETPRA) in preventing the recurrence of antrochoanal polyps and evaluate the outcomes and possible complications of prelacrimal recess approach for treatment of antrochoanal polyps. Patient and Methods: forty patients with antrochoanal polyp underwent surgery with a transnasal endoscopic prelacrimal recess approach. The approach was evaluated for the ability to visualise the origin of the polyp in the maxillary cavity, complications and recurrence of the polyp. Results: Transnasal prelacrimal recess approach was successful in 80% of the patients (32/40), 80% of patients (32/40) did not encounter epiphora postoperatively, 85% of them (34/40) had no epistaxis, 90% of them (36/40) had no cheek edema. None of them had nasal obstruction, nasal stenosis or adhesions, All of them had the flap healed, and all of them had the inferior turbinate preserved. During the follow-up period (1 year) no recurrence had developed. Conclusion: Prelacrimal recess approach is a safe procedure which allows for complete removal of the antral part of the antrochoanal polyps to prevent recurrence without major complications.

Nasal endoscopy prospectsin experimental rhinology: some aspects of enisamium iodide nasal spray effectiveness in rhinosinusitis

Acute rhinosinusitis treatment and prevention is connected to the rational choice of drug dosage form, which will provide the therapeutic effect and the safety of a drug substance or a drug substance complex. Nasal spray with Enisamium Iodide can be used to nasal congestion relief in acute rhinosinusitis because the active substance has an anti-exudative action. Nasal endoscopy could be used in experimental rhinology as a method for direct pathology visualization and for evaluation of the effectiveness of test drugs. Aim: To substantiate Enisamium Iodide (nasal spray) 10 mg/mL effectiveness on maxillary sinus ostium via nasal endoscopy in rabbits with experimental rhinosinusitis. Methods: As a test object was used Enisamium Iodide (nasal spray). As a reference drug, we used BNO-101. Experimental rhinosinusitis was induced in the 1st day. On the 1st , 15th and 25th days in all groups (four groups, six rabbits in each group), we used nasal endoscopy and semi-quantitative assessment to the result objectivity. Results: The total score in the intact control group was 0 (0÷0) on the 15th and 25th days (physiological state). The total score in the control pathology group was 2.0 (2.0÷2.0) and 2.0 (1.0÷2.0) (severe rhinosinusitis) respectively. The total score in Enisamium Iodide treated group was 2.0 (1.0÷2.0) (severe rhinosinusitis) and 0.0 (0.0÷1.0) (physiological state). The total score in BNO-101 treated group was 2.0 (1.0÷2.0) (severe rhinosinusitis) and 1.0 (1.0÷1.0) (mild rhinosinusitis). Conclusions: Nasal endoscopy can be used as an informative visual method. Enisamium Iodide (nasal spray) has been shown a positive effect by endoscopic evaluation of maxillary sinus ostium and exceeded activity of the reference drug.

The Location and Diameter of the Primary Maxillary Sinus Ostium in Malaysians: A Cone-Beam Computerized Tomography Study

Rhinosinusitis is one of widely spread diseases in the region and the role of the anatomical variations in its pathogenesis remains unresolved. A retrospective study using CBCT scan was employed to locate and measure the diameter of 320 primary maxillary ostium (PMO) (n = 160 subjects) among the Malay and Chinese populations (Mongoloid race) in Malaysia. Image analysis was performed using the i-CAT Vision Software, employing the multiplanar reconstruction window in which axial, coronal and sagittal planes were visualized in 0.3 mm intervals. The mean diameter of the PMO was significantly larger in the Chinese than the Malay. Females had larger size than the male and bilateral asymmetry was noticed, where the right side PMO was larger than the left side (p &lt; 0.05). In addition, PMO opened more in the posterior third position of the hiatus semilunaris (61.9%) than anterior and middle third. The PMO showed a statistically significant posteriorly placed position in the Chinese than the Malays and this was more evident in the right side PMO (p &lt; 0.01). In conclusion, the PMO commonly opens in the posterior third of the hiatus semilunaris and its diameter is significantly greater in the Chinese female with evidence of bilateral asymmetry. Awareness the anatomical variation of the Ostium diameter and location among the Malay and Chinese populations potentially has important clinical effects during surgical procedures.

Sphenopalatine Foramen Computed Tomography Landmarks.

The aim of the study was to assess different radiologic bony landmarks for endoscopic localization of the sphenopalatine foramen (SPF). Paranasal computed tomography (CT) scans of adults without sinonasal pathology were included. On axial cuts, the anteroposterior distances from the SPF to maxillary line, anterior head of the middle turbinate, basal lamella of the middle turbinate, choanal arch, and posterior fontanel of the maxillary sinus ostium were measured. While on coronal cuts, the vertical distances from the SPF to the nasal floor was measured. The registered measurements were then studied and statistically analyzed. In 70 patients (140 sides, 840 measurements), the mean distances from the SPF to nasal floor, choanal arch, maxillary line, anterior head of the middle turbinate, basal lamella, and posterior fontanel were 25.6 ± 2.4, 8.5 ± 1.38, 36.4 ± 2.6, 34.6 ± 4.26, 8.1 ± 1.27, and 13.7 ± 1.7 mm, respectively, without significant differences between right and left sides. Females showed significantly shorter mean distances between SPF and the nasal floor (P = 0.0011), choanal arch (P = 0.0459), and posterior fontanel (P < 0.0001) than males. While no significant differences were detected between both sexes as regard distances from SPF to maxillary line (P = 0.5579), anterior head of middle turbinate (P = 0.8581), and basal lamella (P = 0.0638). Preoperative CT can provide multiple easily detected, reliable, and simple bony landmarks that can help SPF endoscopic localization. Thus the authors recommend adding these measurements to the preoperative CT checklist for patients scheduled for sphenopalatine artery ligation and/or excision of vascular lesions.

Visibility, location, and morphology of the primary maxillary sinus ostium and presence of accessory ostia: a retrospective analysis using cone beam computed tomography (CBCT).

This retrospective study evaluated the visibility, location, and morphology of the primary maxillary ostium (PMO), as well as the presence and number of accessory maxillary ostia (AMO) in the maxillary sinus using cone beam computed tomography (CBCT). CBCT scans with a large field of view with both maxillary sinuses entirely visible, acquired from February 2016 to February 2018, were initially screened. Patients were included if there was no history of surgical intervention/trauma in the sinus region. Two observers evaluated the CBCTs for PMO and AMOs independently. PMO and AMOs were evaluated in axial, coronal, and sagittal CBCT views. In case of disagreement, a third observer served as a referee. The findings were correlated with age, gender, condition of the sinus mucosa, and status of the dentition to assess for potential influencing factors. A total of 184 patients (368 maxillary sinuses) were included. PMO was present and patent in 346 (94.0%) of the 368 analyzed sinuses. Most of the PMOs were located above the attachment of and in the middle third of the inferior turbinate (76.1%) and exhibited a slit shape (71.1%). An AMO was present in 167 (45.5%) of the 368 analyzed sinuses, and 66 (17.9%) sinuses had multiple AMOs. Gender and sinus mucosa morphology were found to be influencing factors for the patency of the PMO. Furthermore, gender seems to be influencing the presence of an AMO. Most of the analyzed maxillary sinus cavities in the present population had a patent PMO. Being male and having morphological changes of the sinus mucosa were factors associated with a reduced prevalence of a patent PMO. A maxillary sinus with pathological findings of the mucosa seems to have a reduced prevalence of patent PMOs. Therefore, clinicians should take care to assess any clinical and radiographical sign indicating a potential maxillary sinusitis prior to surgical interventions in this region, especially in cases with planned sinus floor elevation.

Anatomic variations associated with antrochoanal polyps.

Although more than a century has passed since antrochoanal polyps (ACPs) were first defined, etiopathogenesis still remains unclear. The aim of this study was to investigate the relationship between ACPs and sinonasal cavity variations. One hundred and forty-four patients with ACP on paranasal sinus computed tomography scans (ACP group) and 160 paranasal sinuses without ACP (control group) were included into the study. The study group was evaluated in respect of the presence of retention cyst in the contralateral maxillary sinus and sinus bone wall sclerosis thickening. Both groups were also compared with respect to the frequency of sinonasal anatomic variations, nasal septal deviation, variations of the uncinate process insertion, concha bullosa, paradoxical middle turbinate, and accessory maxillary sinus ostium. In the ACP group, the cases with septal deviation (SD) were also evaluated whether the deviation convexity was towards the polyp side or the opposite side. In addition, the posterior extension of ACPs were evaluated in three groups as middle meatus, nasopharynx, and oropharynx extension. The prevalence of retention cyst, sinus wall sclerosis thickening, SD, and accessory maxillary ostium was significantly higher in the ACP group. A negative directional correlation was determined between the SD side and ACP side. When the ACP extensions were examined, middle meatus extension was seen in 32.6%, nasopharynx in 56.3%, and oropharynx in 11.1%. Accessory ostium may be an accelerating factor in the transformation of retention cyst to ACP. Furthermore, the changes in the nasal passage airflow on the opposite side suggest that SD contributes to this process.

EVALUATION OF RELATIONSHIP BETWEEN MAXILLARY SINUS PATHOLOGIES AND OSTIUM DIMENSION: A RETROSPECTIVE CONE BEAM COMPUTED TOMOGRAPHY STUDY

Objective: Maxillary sinus ostium is the top section of the medial wall the and is hence poorly placed from the point of view of free drainage; it opens into the narrow ethmoidal infundibulum, inflammation of which can further break drainage, so this may cause in the development of chronic maxillary sinusitis. This study aims to evaluate maxillary sinus pathologies (MSP) and their possible relation with maxillary sinus ostium dimensions.Material and Methods: Cone Beam Computed Tomography (CBCT) scans which belong to 139 patients (52 male and 87 female) were retrospectively evaluated with regard to ostium dimensions and the presence of MSP including retention cyst and mucosal thickening. Independent Samples t-test and Pearson Chi-Square were used to for statistical analysis.Results: No statistically significant difference was observed between patients with and without MSP in terms of ostium width (p=0.13). While the mean ostium width was 2.08 mm in the patient with MSP it was measured as 2.14 mm in patients without MSP. For all patients examined, right and left ostiums mean widths were 1.97 mm (Range 0.67-4.25) and 2.26 mm (Range 0.67-5.25), respectively. No significant difference was observed in ostium width according to gender (p≥0.05). Among all patients, 18.7% (n=26) had MSP; of these 10 were bilateral and 16 were unilateral. Conclusion: MSP is the common finding in CBCT examinations and the results of this study showed that MSP does not seem to be associated with the ostium width.

Anatomical Variation in Maxillary Sinus Ostium Positioning: Implications for Nasal-Sinus Disease.

Among humans, superiorly located maxillary sinus ostia (MSO) result in drainage complications and maxillary sinus (MS) disease. While previous studies investigate maxillary sinusitis frequency or MSO-position relative to specific nasal landmarks, few explore MSO-position to overall MS dimensions. This study investigates whether MSO-position relates to MS size/shape and if sex-based differences exist. Twenty-nine landmarks, placed on magnetic resonance images (MRIs) of 109 individuals (males = 57; females = 52), captured maximum dimensions of the cranium, MS, nasal cavity, and MSO-position relative to the MS floor (MSO_MSF) and nasal floor (MSO_NCF). Landmark coordinates were used to calculate centroid sizes and 13 linear distances; distances were size standardized by cranial centroid-size. Principal components analysis (PCA) on 3D-coordinates indicates that variation in MSO-position relates to superior-inferior MS positioning within the face (PC1 22% variance) and MS height (PC2 12% variance). Regression analyses indicate that MS size (r2 = 0.502; P < 0.001) and height (r2 = 0.589; P < 0.0001) strongly contribute to MSO_MSF: larger, taller MSs exhibit greater MSO_MSFs. Sex-based differences were not evident in PC shape-analyses nor among size-standardized dimensions. However, Mann-Whitney U-tests indicate females have absolutely smaller MSs (P = 0.001) and MSO_MSF distances (P = 0.001). Further, regressions indicate females exhibit lower MSO_MSFs for a similar MS height. Overall, MSOs superiorly placed relative to the MS floor correlate with larger, taller MSs and/or sinuses positioned inferiorly within the face. While craniofacial surgeons/clinicians should be aware of potential sex-based differences in MS size and MSO position, this study does not suggest that higher incidences of female-reported sinusitis relate to sex-based differences in MS anatomy. Anat Rec, 302:917-930, 2019. © 2018 Wiley Periodicals, Inc.

Posterior Maxillary Sinus Wall: A Landmark for Identifying the Sphenoid Sinus Ostium.

Safe entry into sphenoid sinus is critical in endoscopic sinus and skull base surgery. A number of surgical landmarks have been used to identify the sphenoid sinus ostium during endoscopic endonasal surgery with variable reliability and intraoperative feasibility. To determine if the posterior wall of the maxillary sinus is a reliable landmark to determine the depth of the sphenoid sinus ostium during anterior to posterior dissection. Prospective study of adult patients undergoing endoscopic sinus surgery between August 2016 and September 2017. Measurements were made intraoperatively between the depth of the posterior maxillary sinus wall and sphenoid sinus ostium. The primary measurement is the distance between the depth of the posterior maxillary sinus wall and sphenoid sinus ostium. Additional data points included age, gender, surgical indication, and primary versus revision endoscopic sinus surgery. Forty-five patients (38% male, 62% female) with an average age of 56 were enrolled, resulting in 88 operated sides. The average distance between the depth of the posterior wall of the maxillary sinus and the sphenoid ostium was 1.5 mm ± 1.4 mm. The most common position of the sphenoid sinus ostium was posterior to the level of the posterior maxillary sinus wall (54%), followed by same level (23%) and anterior (23%). There was no significant difference between different disease states (P = .75) and between primary and revision cases (P = .13). The posterior wall of the maxillary sinus serves as an adjunctive intraoperative landmark to determine the depth of the sphenoid sinus ostium. While the posterior wall of the maxillary sinus approximates the depth of the sphenoid sinus ostium, the relative position is variable and can be anterior or posterior.

Bilateral antrochoanal polyp: case report, literature review and clinical guidelines

Antrochoanal polyps are unilateral benign lesions that arise within the maxillary sinus antrum. The purpose of this study was to review the clinical characteristics and treatment of antrochoanal polyp (ACP). A retrospective analysis was performed to investigate the case of one patient with an extremely rare bilateral polyp with a high incidence of recurrence. ACPs account for approximately one-third of polyps occurring in children. Most of them are unilateral. The recurrent course of ACP is more prevalent in the paediatric population than in adults. ACPs require differential diagnosis with malignancies. The mainstay of treatment is surgery. The gold standard is endoscopic sinus surgery with complete removal of polyp mass under endoscopic control and widening of the maxillary sinus ostium via the middle meatus. Postoperative follow-up of at least 2 years is very important to monitor patients for recurrence.

Maxillary sinus ostium assessment: A CT study

ObjectiveTo assess the maxillary sinus ostium (MSO) dimension and measuring the distance to nearby anatomical structures in adults using multi-slice computed tomography (MSCT). Patients and methodsParanasalCT scans of asymptomatic adults withoutparanasalsinuses or nasal pathologywere included. Axial CT with coronal reformatted imageswas donefor all subjects to get delicate details. ResultsIn 86 subjects (172 sides), the width of MSO ranged from 1 to 11 mm and distance from the MSO to the anterior maxillary wall (towardnasolacrimalduct) ranged from 7 to 25 mm. Whilethe distance fromMSO to the posterior maxillary wall (towardsphenopalatineartery) ranged from 2 to 18 mm. MSO was found above orbital floor level in 74%, at the orbital floor level in 12% and below this level in 13% of our cases. Distance from MSO to the floor of maxilla ranged from 15 to 40 mm (mean = 28.6 ± 6.7).MSOwas detectedin the posterior third of medial maxillary wall in 47%,in middle third in 32% and the anterior third in only 21%.Anteroposteriordiameter of maxillary sinus ranged from 18 to 41 mm. Its horizontal diameter ranged from 10 to 35 mm and its height ranged from 15 to 45 mm. For all measurements of the maxillary sinus and MSO, the differences between right and left side were non-significant. ConclusionThis work describes in details MSO measurements usingMSCTand measures the distance from the MSO to the beyond adjacent anatomical structures in the all directions.