Gender differences in ethmoid sinus morphology_ 3D reconstruction of computed tomographic images.

BACKGROUND: The ethmoid sinus (ES) is a three-dimensional (3D) complex structure, a clear understanding of the ES anatomy is helpful to plan intranasal surgery. However, most prior studies use 2D measurements, which may not accurately depict the 3D structure. The current study measured the gender differences in ES morphology based on 3D reconstruction of computed tomography (CT) images. METHODS: The 3D models were reconstructed using CT images. Twenty-one males and 15 females were enrolled in the study. The ES dimensions, including width, height and aspect ratio (AR) of each cutting-plane section, were measured at 10% increments along with the anteroposterior axis of the ES. The gender differences in the above parameters were further evaluated by an independent t-test. RESULTS: The width of the ES for males is 12.0 ± 2.1 mm, which was significantly greater than that in females (10.0 ± 2.1 mm). The average height for males is 18.4 ± 3.5 mm, and 18.2 ± 3.4 mm for females. The AR of female (male) is around 0.56 (0.63) for the anterior ES and 0.66 (0.75) for the posterior. There are significant differences between genders in the parameters of width and AR (p < 0.05). CONCLUSION: This study found that the aspect ratio greatly varies along the length of ES, indicating that the cross-section of the ES in the anterior is closer to an elliptical shape and turns closer to a circular shape near its posterior. There is a significant difference between genders in width and aspect ratio. The results would be helpful to know the complex anatomic details of the ethmoid sinus.

[Based on CT imaging, surgical approach selection for frontal and ethmoid sinus osteoma].

Objective:To investigate the criteria for selecting surgical approaches for frontal and ethmoid sinus osteomas of different locations and sizes on CT imaging. Methods:Using sagittal and coronal CT images, the following lines were delineated: the F-line（a horizontal line passing nasofrontal beak）, the M-line（a vertical line passing paries medialis orbitae）, and the P-line（a vertical line passing the center of the pupil）. Classification of frontal and ethmoid sinus osteomas was based on their relationship with these lines. Appropriate surgical approaches were selected, including pure endoscopic approaches, endoscopic combined with eyebrow incision approach, and endoscopic combined with coronal incision approach. This method was applied to a single center at the Third Affiliated Hospital of Sun Yat-sen University for endoscopic resection of frontal and ethmoid sinus osteoma. Case Data: Sixteen cases of ethmoid sinus osteomas were treated from January 2020 to September 2023. Among these cases, there were 9 males and 7 females, with ages ranging from 18 to 69 years, and a median age of 48 years. Results:Thirteen cases underwent pure endoscopic resection of the osteoma, while in three cases, a combined approach was utilized. Among the combined approach cases, two exceeded both the M-line and the F-line but did not cross the P-line; therefore, they underwent endoscopic combined with eyebrow incision approach. One case exceeded all three lines and thus underwent endoscopic combined with coronal incision. In all cases, complete resection of the osteoma was achieved as per preoperative planning, and none of the patients experienced significant postoperative complications. Conclusion:For frontal and ethmoid sinus osteomas, it is advisable to perform a thorough preoperative radiological assessment. Based on the size of the osteoma and its relationship to the three lines, an appropriate surgical approach should be chosen to optimize the diagnostic and treatment plan.

Bilateral sinonasal inverted papillomas originating from both sides of the frontal sinus and the left lamina papyracea: A case report.

RATIONALE: The present investigation documented a case of bilateral sinonasal inverted papilloma (SNIP) that arose from both sides of the frontal sinus and ethmoid sinus. The occurrence of bilateral involvement of the nasal cavities and frontal sinus is rather infrequent. PATIENT CONCERNS: Informed consent was obtained from the patient. DIAGNOSIS: Bilateral SNIP. INTERVENTIONS: The tumor was completely removed by Draf III endoscopic resection complemented by an external eyebrow arch approach, and the postoperative recovery was uneventful. OUTCOMES: The purpose of this paper is to present a comprehensive reference for the management of bilateral SNIP that affects the frontal sinuses. LESSONS: This study addresses the staging and surgical management of bilateral SNIP, along with a review of the factors contributing to its recurrence. The recommended treatment method involves applying the Draf III technique combined with an external nasal approach.

[Cerebrospinal fluid rhinorrhea secondary to ethmoidal carcinoma: case report]. / Rinorrea de líquido cefalorraquídeo secundaria a carcinoma etmoidal: reporte de caso.

BACKGROUND: The first report of cerebrospinal fluid rhinorrhea (CSFR) was described in 1679. In 1826 it was reported that one of the possible causes of CSFR was a fistula between the subarachnoid space and the nasal cavity. In 1903, chemical analysis of the fluid was proposed as a diagnostic criterion. In Mexico there has been 32 case reports. CASE REPORT: Forty-nine years old female with a history of nasal polyposis, profuse rhinorrhea and cephalea who attends the allergy department with the suspicion of allergic rhinitis. After anamnesis and physical evaluation, CSFR was suspected. Chemical analysis of the fluid, head CT and biopsy of nasal polyp were performed. An etmoidal fistula associated with carcinoma was confirmed. CONCLUSIONS: Spontaneous fistulas are rare but can erosionate the bone and adjacent tissues. Diagnosis is based on the clinical findings, patient's history and complementary studies such as beta-2-transferrin determination in nasal fluid.

ANTECEDENTES: En 1679 se describió el primer caso de rinorrea de líquido cefalorraquídeo. En 1826 se reportó como causa una fistula entre el espacio subaracnoideo y la cavidad nasal. Para 1903 se propuso el análisis químico como criterio diagnóstico. En México sólo se han reportado 32 casos de rinorrea de líquido cefalorraquídeo. REPORTE DE CASO: Paciente femenina de 49 años, con antecedente de poliposis nasal, rinorrea abundante y cefalea, quien acudió a consulta para descartar rinitis alérgica. Luego de la anamnesis y la exploración física se sospechó de fuga de líquido cefalorraquídeo secundaria a fístula nasal. Con la histoquímica de moco, tomografía de cráneo y biopsia del pólipo nasal se estableció el diagnóstico de fístula etmoidal secundaria a carcinoma. CONCLUSIÓN: La fístulas espontáneas son excepcionales, pueden erosionar el hueso y los tejidos adyacentes. El diagnóstico se establece con la historia clínica y los antecedentes médicos, además de estudios complementarios y la determinación de Beta-2-transferrina en moco.

Are the Ethmoidal Foramina Through the Frontal Bone, Ethmoid Bone, or Frontoethmoidal Suture?

INTRODUCTION: To investigate the locations of the anterior, middle, and posterior ethmoidal foramina and their relationships to the frontoethmoidal suture. METHODS: One hundred twenty sides from sixty adult human skulls were used. Specimens with significant damage to the medial orbit wall were excluded. The number of ethmoidal foramina (anterior, middle, and posterior) on the medial orbital wall and the relationship of each foramen to the frontoethmoidal suture were recorded and classified as follows: Type I: superior to the frontoethmoidal suture; Type II: on the frontoethmoidal suture; Type III: inferior to the frontoethmoidal suture. RESULTS: Of the ninety-four sides, fourteen (14.9%) had one foramen, sixty-two (66.0%) had two , and eighteen (19.1%) had three. In total, 192 ethmoidal foramina were observed. Among the fourteen sides with one foramen, eight foramina were anterior and six were posterior. Among the 192 ethmoidal foramina, 162 were eligible for fur ther classification (74 anterior, 14 middle, and 74 posterior). Types I, II, and III ethmoidal foramina were found in 38.3% (62/162), 61.7% (100/162), and 0% (0/162), respectively. CONCLUSIONS: Our current study found a higher incidence of type I than previously reported. It is important to be aware of the significant incidence of foramen variations when the medial orbit wall is manipulated during surgery. Unless caution is observed, an inadvertent surgical injury can occur and lead to life-threatening complications. Therefore, a good understanding of orbital anatomy and its potential variations is critical for improving patient out comes.

The Upper Attachment of the Uncinate Process and Anterior Ethmoidal Artery.

OBJECTIVE: Variations in the upper attachment of the uncinate process (UP) are important because they can affect frontal sinus drainage and change the morphology. Functional endoscopic sinus surgery (FESS) is the primary technique used to treat chronic medically refractory rhinosinusitis. Uncinectomy is the basis of FESS technique to obtain the best possible result from surgery. The anterior ethmoidal artery (AEA) enters the nasal cavity through the orbital medial wall (lamina papyracea) may also be affected by the upper attachment of the UP. The aim of this study was to investigate a possible link between UP variations and the course of the AEA. MATERIALS AND METHODS: This retrospective, computed tomography (CT)-based, anatomic study was conducted on 200 healthy adults (100 females and 100 males) by screening bilateral paranasal sinus images. The upper attachment of the UP was classified in 6 types (1-6) based on the Liu classification. The AEA was divided into 4 types (A-D) based on location: anterior to the frontal sinus (A), between the frontal sinus and the middle nasal turbinate (B), and anterior to the posterior ethmoidal cells (C and D). All the CT images were evaluated simultaneously by 2 anatomists and 1 radiologist. RESULTS: Of the total cases (200 right and 200 left side), 48.8% were type 1 UP attachment, 11.0% type 2, 12% type 3, 9% type 4, 18% type 5, and 1.2% type 6. The AEAs were classified as 12.2% type A, 71.8% type B, 15.2% type C, and 0.8% type D. CONCLUSION: The course of the AEA through the nasal cavity was observed to shift anteriorly from the ethmoidal bulla to the frontal sinus in patients with UP attached to the lamina papyracea and middle turbinate. Remarkably, the AEA always coursed anterior from the middle nasal turbinate line.

Examination of ethmoidal roof regarding Keros and Yenigun classifications in a Turkish population: a computerized tomography study.

PURPOSE: Understanding ethmoid roof morphology is crucial to prevent complications in endoscopic sinus surgery. This study aimed to evaluate the morphological properties of the ethmoidal roof regarding gender and age differences using Keros and Yenigun classifications on high-resolution computed tomography images. METHODS: We retrospectively analyzed 891 high-resolution computed tomography paranasal sinus study images and measured the depth of the cribriform plate in coronal sections and the anterior-posterior length in axial planes. The study retrospectively examined CT images of paranasal sinuses of patients living in the eastern Anatolian region of Turkey. RESULTS: In both Keros and Yenigun Classifications, the most common class was type 2, and the least common class was type 3. According to Keros et al.'s method, no significant difference was observed between men and women (p = 0.698). However, according to Yenigun et al., the average values of women in terms of the anterior-posterior distance of the ethmoid roof were significantly higher than men (p = 0.001). When examined according to age, a very low, negative correlation was revealed regarding Keros and Yenigun classifications (p = 0.047 and p < 0.001 retrospectively). According to Keros and Yenigun's classification, there was no significant difference between the left and right sides (p = 0.488 and p = 0.919, respectively). CONCLUSION: The morphological properties of the ethmoidal roof have importance to be considered for preoperative planning. Studying larger patient groups and meta-analyses that gather various research results about this subject might help better understand the ethmoidal roof morphology among populations.

Relation between anterior ethmoidal artery course on computed tomography and supraorbital ethmoid cell and Keros classification.

PURPOSE: The anterior ethmoidal artery (AEA) is an important risk area in endoscopic sinus surgery. This study aimed to evaluate the course of AEA according to the Keros classification and the presence of supraorbital ethmoid cell (SOEC) and to prevent possible complications by emphasizing the importance of preoperative paranasal computed tomography (CT) imaging. This approach will increase the effectiveness of endoscopic sinus surgery and improve patient safety. METHODS: The paranasal CT scan images of patients aged > 18 years between October 2020 and November 2021 from our center were retrospectively analyzed. The images were primarily evaluated in the coronal plane, and the sagittal and axial planes were utilized to evaluate variations in AEA regarding the skull base. Furthermore, the relation of AEA course with Keros classification and SOEC was evaluated. The study included 1000 patients aged 18-80 years (right and left, a total of 2000 samples). RESULTS: Grade 3 AEA was the most common regarding the skull base. Keros Type 2 was the most common classification. Overall, 48.7% patients had SOEC. The incidence of Grade 3 AEA was higher among patients with SOEC and a higher Keros classification compared with those without SOEC and a lower Keros classification. Furthermore, Keros Type 3 was the most associated with SOEC presence. CONCLUSION: Consistent with the literature, the probability of Grade 3 AEA in patients with high Keros classification and SOEC was significantly higher in our study. Therefore, we consider that preoperative imaging according to Keros classification and SOEC presence can predict AEA course and guide surgery.

Impact of facility volume on survival in primary endoscopic surgery for sinonasal squamous cell carcinoma.

OBJECTIVES: To evaluate the impact of facility volume on outcomes following primary endoscopic surgical management of sinonasal squamous cell carcinoma (SNSCC). METHODS: The 2010-2016 National Cancer DataBase (NCDB) was queried for patients diagnosed with T1-T4a SNSCC surgically treated endoscopically as the primary treatment modality. Factors associated with overall survival (OS) were evaluated, including facility volume. RESULTS: A total of 330 patients who underwent endoscopic surgical management of SNSCC were treated at 356 unique facilities designated as either low-volume (LVC; treating 1-2 cases; 0-75th percentile), intermediate-volume centers (IVC; 3-4 cases total; 75th-90th percentile), or 144 high-volume (HVC; treating 5+ cases total; >90th percentile) centers. HVC treated patients with higher T staging (42.1 % vs. 29.8 %) and tumors in the maxillary sinus (26.9 % vs. 13.2 %) and ethmoid sinus (10.3 % vs. ≤8.3 %), while LVCs treated lower T stage tumors (70.2 % vs. 57.9 %) and tumors that were located in the nasal cavity (70.2-78.5 % vs. 62.8 %). On multivariable analysis, factors associated with decreased OS included higher T stage (T3/T4a vs. T1/T2; OR 1.92, 95 % CI 1.06-3.47) and older age (>65 vs. <65; OR 2.69, 95 % CI 1.62-4.49). Cases treated at high-volume centers were not associated with a higher likelihood of OS when compared to low-volume centers (OR 0.70, 95 % CI 0.36-1.35). CONCLUSIONS: HVC are treating more primary tumors of the maxillary and ethmoid sinuses and tumors with higher T stages with endoscopic approaches, although this does not appear to be associated with increased OS. SHORT SUMMARY: Sinonasal squamous cell carcinoma (SNSCC) presents late in disease process with poor prognosis. We investigated the impact of facility volume on outcomes following endoscopic treatment of SNSCC. High-volume centers treat more advanced and complex disease with comparable OS.

A Consistent Endoscopic Landmark to Identify the Anterior Ethmoidal Artery.

OBJECTIVE: The anterior ethmoidal artery (AEA) is an important structure to identify during endoscopic sinus surgery. Although identification on imaging is easily taught, a consistent endoscopic landmark for the AEA, independent of anatomic ethmoid cell variation, is lacking, leaving many surgeons unclear about the exact location without dependence on navigation. Here, we describe a consistent endoscopic landmark, regardless of anatomical ethmoid variation. METHODS: We prospectively enrolled adult patients undergoing endoscopic surgery involving frontal and ethmoid sinuses in this observational study. The AEA landmark was defined simply as the septation or ridge one step back along the ethmoid skull base from the posterior table of the frontal sinus. The gold standard to calculate the sensitivity of our endoscopic landmark was an image-navigation system, registered to within 1.5 mm accuracy, locating the AEA within three planes. Both endoscopic and computerized tomography (CT) images of the pointer at the landmark were taken simultaneously. The concordance of endoscopic to navigation images was independently assessed by three blinded rhinologists. RESULTS: Forty patients were included in our study with 73 sides analyzed. Diagnoses included chronic rhinosinusitis without polyps (52.5%), with polyps (22.5%), recurrent acute sinusitis (15%), sinonasal tumors (7.5%), and odontogenic sinusitis (2.5%). The AEA was accurately identified using our endoscopic landmark in 97.3% of the cases (71/73). Of the two cases in which the AEA was not found within the landmark, the artery was located ≤1 mm posteriorly. CONCLUSION: We describe a consistent endoscopic landmark to identify the AEA, conserved across various clinical diagnoses and anatomic variations in sinus structure. LEVEL OF EVIDENCE: 3 Laryngoscope, 134:1096-1099, 2024.

Comparing Endoscopic Measurements of the Anterior and Posterior Ethmoidal Arteries with CT Measurements: A Cadaveric Study.

OBJECTIVE: To reveal the reliability of radiological measurements of the ethmoid arteries. METHOD: Five fresh frozen cadaveric heads underwent computed tomography and endoscopic sinus surgery. The lateromedial length of the anterior ethmoidal artery (AEA) and its distance to the axilla of the middle turbinate (MTA), the sphenoethmoidal recess (SR) and the posterior ethmoidal artery were measured. The posterior ethmoidal artery (PEA) was referenced to the SR. These anatomical parameters were measured both radiologically and endoscopically, and the compatibility of the two was examined. RESULTS: Ten nasal cavities were dissected. We found that the distance of MTA to the AEA was 16±8 mm in dissection, 21±4 mm radiologically in the sagittal section, the distance of SR to the AEA was 14±3 mm in dissection, 19±4 mm radiologically in the sagittal section, and the distance of the AEA to the PEA was 10±3 mm in dissection, 12±3 mm radiologically in the axial section. The distance of the PEA to SR was 6±3 mm in dissection, 8±2 mm radiologically in the sagittal section. CONCLUSIONS: The distance of the AEA to the MTA, the distance of the AEA to the PEA and the distance of the PEA to the SR were compatible with each other in the dissection and in the radiologically evaluation, whereas the distance of the AEA to the SR was not compatible.

Maxillary ostium preservation in ethmoidectomy.

The paranasal sinuses play a role in producing and storing nitric oxide (NO). NO is a powerful antiviral and antibacterial gas which may be involved in the non-specific immune defenses of the respiratory tract. Conducted by the inspiratory current at the alveolar-capillary membrane, it increases pulmonary venous blood oxygenation. NO is actively released in the form of independent boluses in the respiratory tract, thanks to a sphincter function that can be identified during ethmoidectomy under general anesthesia. Safeguarding paranasal sinus physiology necessarily involves conserving this ostial sphincter function, which is essential to the respiratory role of the paranasal sinuses. Although it has not yet been demonstrated that the destruction of this ostial function has measurable consequences for respiratory function, it makes sense to avoid systematic antrostomy and to preserve this ostial function whenever possible, depending on the clinical conditions. This technical note describes step-by-step how to conserve the maxillary ostium, in the example of radical ethmoidectomy with mucosal ablation for nasal polyposis (nasalization). It is illustrated by two videos. The discussion focuses on the respective indications for ostial preservation and middle meatotomy (antrostomy).

Resection of Orbital Myxoma With Magnetic Resonance Imaging Evidence of Ethmoid Sinus Origin: Case Report and Review of 20 Patients in the Literature.

A 41-year-old woman showed a palpable mass at the superonasal orbital edge on the right side. Magnetic resonance imaging demonstrated a lobulated fluid-containing tubular mass which extended anteriorly to posteriorly along the medial orbital wall, nasal to the eyeball. She was followed once a year for 8 years until the age of 49 years when she decided to undergo surgical resection because of the enlarged mass. The lobulated large mass was resected and the pathology showed sparsely distributed spindle cells, positive for CD34, in alcian blue-positive mucous substances, indicative of myxoma. Postoperative magnetic resonance imaging showed residual lobulated tubular mass along the optic nerve on the medial side and superior to the eyeball. The residual orbital mass showed stable structure with more evident connection with the ethmoid sinus lesion, suggestive of the ethmoid origin, in 12 years until the age of 61 years. In the review of 20 patients with orbital myxomas in the literature, in addition to this case, roughly classified locations in the orbit were retrobulbar in 8 patients, on the lateral side of the orbit in 4, on the superior side in 6, on the medial side in 1 (this patient), and in the orbit with no specific description in 2. In pathological examinations, immunohistochemistry was not done in 8 patients, done but all negative in 2, and positive in 11 patients: nerve sheath myxoma was diagnosed in 3 patients based on positive S100 staining. Orbital myxoma is rare but considered in differential diagnosis of orbital masses.

Clinical and imaging features of ethmomaxillary sinus compared to Haller's cell.

PURPOSE: Understanding the anatomy of the paranasal sinuses and their variations is essential to achieving safe and effective endoscopic sinus surgery. The ethmomaxillary sinus (EMS) is a relatively under-researched anatomical variation. This study investigated the prevalence, clinical features, and effect of EMS on the maxillary sinus in comparison with Haller's cells. METHODS: Patients who visited the Rhinology Clinic at our hospital for rhinologic symptoms between January 2020 and December 2020. Computed tomography (CT) scans of paranasal sinuses were obtained at 1 mm-section thickness. Using CT scans, we investigated the clinical features of EMS, measured maxillary sinus volume, and analyzed the presence of maxillary sinusitis. RESULTS: EMS was observed in 26 of the 250 patients (10.4%). The male-to-female ratio was equal. The age ranged from 18 to 83 years (mean age, 56.3). Of the patients with EMS, 65.4% were unilateral and 34.6% were bilateral. The prevalence of Haller's cells was similar to that in EMS (10.8%). In the analysis of patients with unilateral EMS, the EMS side was found to have a significantly reduced maxillary sinus volume compared to the opposite side, whereas the difference was not significant in Haller's cells. There was no significant relationship between EMS or Haller's cells and maxillary sinusitis. CONCLUSIONS: EMS can significantly affect maxillary sinus volume. Therefore, surgeons should thoroughly review PNS CT scans before paranasal sinus surgery to determine the presence and features of EMS.

SMARCB1-Deficient Sinonasal Carcinoma: Case Report and Review of the Literature.

BACKGROUND SMARCB1-deficient sinonasal carcinoma is a rare neoplasm with inactivation of the SWI/SNF complex, with an aggressive clinical course as most of the lesions present as advanced in pT3/T4 stages with frequent recurrence, and many patients succumb to the disease. Reported initially in 2014, the lesion has male predominance, with an age range of 19 to 89 years and predilection for the ethmoid sinus and nasal cavity. Histopathological findings show a proliferation of small- to medium-sized monomorphic basaloid cells with indistinctive cytoplasmic borders and round variably prominent nuclei with scattered cells that show rhabdoid morphology. Cytoplasmic vacuoles are common. It has similar morphological findings to a wide array of neoplasms in the sinonasal area. CASE REPORT We report a case of SMARCB1-deficient sinonasal carcinoma in a 30-year-old man referred to our hospital with a preliminary diagnosis of sinonasal adenocarcinoma, intestinal type. Computed tomography showed a huge destructive soft tissue mass in the left maxillary sinus, extended to involve the left nasal cavity with extension to the skull base and perineural spread along the foramen rotundum. Histological examination revealed a malignant basaloid neoplasm embedded in a myxoid stroma that showed loss of SMARCB1 stain. The patient was treated with induction chemotherapy using etoposide and cisplatin for disease control. CONCLUSIONS SMARCB1-deficient sinonasal carcinoma is a rare neoplasm with an aggressive clinical course and high-grade behavior despite having uniform cytological features. This poses complex diagnoses, especially in small biopsies. Incorporating morphological findings with ancillary tests is required to identify this high-grade malignancy.

Osteoma of the ethmoid sinus in a pediatric patient - a case report.

BACKGROUND: Osteomas of the paranasal sinuses occur rarely in the pediatric population, we find only a few reference of symptomatic osteomas in the literature. Opinions on the indication for surgical treatment are controversial. CASE: The authors present a case of symptomatic osteoma of the right ethoimoidal sinus in a 12-year-old boy, who was treated surgically, with endoscopic endonasal approach. The symptomatology, diagnosis and therapy of these tumors in the pediatric patient are discussed. CONCLUSION: Osteomas of the paranasal sinuses are slow-growing benign lesions. Symptomatic osteomas can grow expansively and cause serious complications. The treatment of osteoma is surgical and the endoscopic approach offers the possibility of removal with cosmetic benefits.

[Efficacy of glucocorticoid stent implantation in ethmoid sinus after endoscopic sinus surgery for chronic rhinosinusitis with nasal polyps].

Objective:To evaluate the efficacy of glucocorticoid sinus stents implanted 2 weeks after functional endoscopic sinus surgery（FESS） for the treatment of chronic rhinosinusitis with nasal polyps（CRSwNP）. Methods:CRSwNP patients with similar bilateral lesions were randomly divided into two groups, with a stent group of 25 patients and a control group of 24 patients. Patients in the stent group had glucocorticoid sinus stents implanted into the bilateral ethmoid sinuses 2 weeks after FESS, while the control group underwent postoperative debridement only. Follow-up assessments occurred at postoperative weeks 2, 4, 8, and 12. Patients were asked to assess their sensation of nasal symptoms using a 10-point visual analog scale. Efficacy was assessed by endoscopic evaluations. Sinus obstruction, crusting/coagulation, polyp formation, middle turbinate position, adhesions, mucosa epithelialization, and postoperative intervention were assessed as efficacy outcomes. GraphPad Prism 9 was applied for statistical analysis. Results:At 4 and 8 weeks postoperatively, the stent group showed significant improvement in VAS scores of nasal congestion and runny nose compared with the control group（P<0.05）. No significant difference was observed in the VAS scores of head and facial stuffiness, loss of smell, or nasal dryness/crusting between the two groups（P>0.05）. Compared with the control group, the stent group had a lower rate of polypoid formation at 4, 8, and 12 weeks postoperatively. At postoperative week 12, the rate of mucosal epithelialization in the ethmoid cavity was significantly higher in the stent group. During the follow-up, the frequency of postoperative intervention was significantly lower in the stent group than in the control group（P<0.05）. Besides, a lower incidence of middle turbinate lateralization was found in the stent group at 8 and 12 weeks postoperatively. At 8 weeks postoperatively, the stent group had a percentage of adhesion lower than that of the control group（all P<0.05）. Conclusion:Implantation of glucocorticoid sinus stents after FESS can maintain sinus cavity patency, improve the inflammatory status of the operative cavity, reduce postoperative interventions, and promote benign regression of the operative cavity.

CT analysis of predictors for visual acuity in optic neuropathy with mucocele.

OBJECTIVE: To evaluate the causative and risk factors for optic neuropathy with mucocele via imaging studies. METHODS: We included 21 patients with rhinogenous optic neuropathy with mucocele. We collected data on the sinus involved, age, sex, number of days from the onset of visual impairment to surgery, and computed tomography (CT) imaging findings (bone defects in the lamina papyracea, Onodi cell mucocele, exophthalmos, and optic nerve deviation). The results were compared between two groups, the one having nine patients with pre-operative visual acuity of <0.1 (the poor group) and the other having 12 patients with pre-operative visual acuity of ≥0.1 (the fair group). Whether or not there was a difference in pre-operative visual acuity between patients with and without Onodi cell mucocele was determined. RESULTS: After surgery, visual acuity improved in 16/21 (76.2%) patients, and a correlation analysis showed a significant positive correlation between pre-operative and post-operative visual acuity. In imaging, the causative sinuses accounted for 85.7% of both posterior ethmoid and sphenoid sinuses. Bone defects of the lamina papyracea at the optic canal and the vertical downward deviation of the optic nerve at each location, especially in 6/9 patients with Onodi cell mucocele, were characteristic in the poor group. In these conditions, increasing the contact areas of the optic nerve and mucocele can leads to more chances of direct downward compression of the optic nerve and infection occurring, and it may lead to severe pre-operative visual impairment. CONCLUSION: Imaging studies of optic neuropathy with mucocele help to determine the risk factors and perform early and precise diagnostic imaging and decision-making for surgery.