A new surgical technique to increase airflow in the olfactory cleft: superior turbinate lateralization procedure.

BACKGROUND: The olfactory cleft (OC) is the most important anatomical site for the maintenance of olfactory function. Obstruction of airflow in the OC by various conditions, such as inflammation, leads to poor olfactory function. Therefore, it is important to increase OC airflow while performing endoscopic sinus surgery (ESS). However, no technique to increase airflow has yet been established. METHODS: We designed a superior turbinate lateralization (STL) procedure that displaces the entire ST bone laterally by eliminating the connection between the posterior ST and the anterior wall of the sphenoid sinus. The effect of the STL procedure was investigated in terms of anatomy and olfactory function. RESULTS: ESS with the STL procedure was performed on seven patients with chronic rhinosinusitis and nasal polyps. The cross-sectional area of the OC at 3 months postoperatively was significantly larger than that before ESS. In addition, the Open Essence test and questionnaires revealed significantly improvements in sense of smell. Airflow in the OC was significantly higher in STL procedure group than in the non-STL procedure group. CONCLUSION: The STL procedure enlarges the bony framework of the OC, and by increasing OC airflow, facilitates the transport of odorants to the olfactory epithelium, thereby improving olfactory perception.

Nasal Packing Materials and Placement Duration on Wound Healing in Nasal Mucosa: An Animal Study.

OBJECTIVE: The histological findings of wound healing depending on different nasal packing materials and replacement periods were lacking. METHODS: Mucosal defects were created in the nasal septum of rabbits and covered with Spongel®, Algoderm®, or Nasopore®, which were cleaned on Day 14. To investigate the effect of replacement durations, Spongel® was removed on Days 3 and 7. All nasal septal specimens were collected on Day 28. Samples without packing material were prepared as controls. Depending on residual packing materials in the regenerated tissue, specimens were classified into the remnant and non-remnant groups, and morphology was compared using epithelium grade score and subepithelial thickness. RESULTS: The epithelium grade score in the Spongel-14d group was lower than that in the other groups (p < 0.05). Subepithelial thickness was higher in the Algoderm-14d and Spongel-14d groups (p < 0.05). Epithelium grade scores were higher and subepithelial thicknesses were lower in the Spongel-3d and -7d groups than in the Spongel-14d group. Epithelium grade score was lower and subepithelial thickness was higher in the remnant group (n = 10) than in the non-remnant group (n = 15; p < 0.05). CONCLUSIONS: Differences in packing materials and placement durations affected wound healing of nasal mucosa. The selection of appropriate packing materials and replacement duration was considered essential for ideal wound healing. LEVEL OF EVIDENCE: NA Laryngoscope, 134:562-568, 2024.

Simple and safe resection of the crista galli.

A critical procedure in the transcribriform approach is the resection of the crista galli. However, the standard technique for crista galli resection has several disadvantages. We reviewed the cases of patients with olfactory neuroblastomas who underwent an endoscopic endonasal transcribriform approach using a newly developed technique for crista galli resection. We performed a cadaveric study to measure the superior accessibility limits using the proposed method. We included 38 patients with olfactory neuroblastomas in this study. The tumor invaded the posterior crista galli in four patients. The anterior end of the crista galli was not invaded by the tumor. Our cadaveric study showed that the dura was approachable to the point that was 7.4 ± 1.3 mm superior and 23.2 ± 7.2 mm lateral to the foramen cecum following crista galli removal. By resecting the crista galli in advance, manipulation of the superior dura became feasible.

The impact of multidisciplinary approaches on the outcomes of olfactory neuroblastoma treated with postoperative radiotherapy.

BACKGROUND: We investigated the outcomes of postoperative radiation therapy for olfactory neuroblastoma (ONB) and our cross-departmental collaboration to enhance the effectiveness of cancer treatment. METHODS: We retrospectively evaluated 22 patients with ONB who underwent postoperative radiotherapy after tumor resection. En bloc resection was performed; pathology specimens were prepared in coronal sections; and irradiation fields were determined after discussion with radiation oncologists, head and neck surgeons, and pathologists. RESULTS: The overall survival and local control rates were 95.5% and 100%, respectively, at a median 37-month follow-up. The 3- and 5-year disease-free survival (DFS) rates were 64.4% and 56.3%, respectively. Of the 22 patients, 9 (8 Kadish C and 1 Kadish B) had disease recurrence. Of the nine patients, five had positive margins and two had closed margins; cervical lymph node recurrence occurred in six, and distant metastasis with or without cervical lymph node recurrence occurred in three. DFS analysis of risk factors showed no statistically significant differences, but positive margins were a significant recurrence factor in multivariate analysis. CONCLUSIONS: The local control rate of ONB treated with postoperative radiation therapy was 100%. This may be attributed to cross-departmental cooperation between head and neck surgeons, pathologists, and radiation oncologists, which resulted in accurate matching of CT images for treatment planning with the location of the tumor and positive margins. Longer follow-up periods are required to evaluate the effectiveness of our strategy.

A Case of Granulomatosis with Polyangiitis (GPA) Where a Multicystic Nasal Septal Abscess Aided in the Diagnosis.

A 69-year-old male patient presented to the hospital with a chief complaint of nasal obstruction. Physical examination revealed swelling of the anterior nasal septum and nasal dorsum and tender indurated oedema of the dorsum of both hands. Blood tests showed an elevated inflammatory response, and contrast-enhanced computed tomography (CT) showed a polycystic abscess in the nasal septum. Emergency surgery and histopathology were performed on the day of the initial visit for incisional drainage. Intraoperative findings showed white necrosis between the nasal septal cartilage and nasal septal mucosa, as well as white necrosis and pus accumulation in the periosteum and soft tissue of the piriform aperture and the nasal bone. The patient underwent endoscopic dissection and drained as much as possible, and the abscess and surrounding normal nasal septal mucosa were sampled for diagnostic purposes. The patient was diagnosed with vasculitis based on the clinical findings, pathological examination results, and blood test results. After the diagnosis was confirmed, steroid and cyclophosphamide pulse administration was initiated, and the swelling of the anterior nasal septum and nasal dorsum and the bilateral dorsal indentation oedema improved markedly. The patient is now doing well and will continue to be carefully monitored in the outpatient clinic.

Mucosal Epithelial Preservation of Free Nasal Grafts Depending on the Recipient Site.

OBJECTIVES/HYPOTHESIS: Reconstruction of mucosal defects using free mucosal grafts has become a common procedure during endoscopic sinus surgery. Epithelialization of mucosal grafts affects postoperative complications and outcomes, which could be influenced by different recipient tissue. However, morphological changes occurring in the grafts transplanted over different tissues remain unexplored. STUDY DESIGN: An animal study. METHODS: Free mucoperichondrial grafts were prepared from the nasal septum of rabbits; the cartilage group had reconstruction on the nasal septal cartilage, and the perichondrium group had reconstruction on the contralateral perichondrium. The nasal septum was removed after 1 and 4 weeks of reconstruction, and the graft was histologically evaluated. RESULTS: After 1 week of reconstruction, the mucosal epithelium of grafts in the cartilage group disappeared, whereas the columnar epithelium of grafts was preserved in the perichondrium group. After 4 weeks of reconstruction, the mucosal defect site was covered with mucosal epithelium in both groups. However, while squamous epithelium was mostly observed in the cartilage group, columnar epithelium containing the healthy ciliary and goblet cells was observed in the perichondrium group. Statistically significant differences were detected in the parameters of epithelial morphology between the two groups, which were higher in the perichondrium group. CONCLUSIONS: In the reconstruction of mucosal defects using free mucosal grafts, difference in recipient tissue affects the graft epithelial morphology. LEVEL OF EVIDENCE: NA Laryngoscope, 132:2301-2306, 2022.

Heterogeneous distribution of mature olfactory sensory neurons in human olfactory epithelium.

BACKGROUND: The olfactory cleft (OC) comprising the olfactory epithelium (OE) is the most important anatomical location for olfactory function. Endoscopic sinus surgery (ESS) is used to treat diseases related to the OC and improve olfactory dysfunction. However, iatrogenic OE injury occasionally occurs. Comprehensive knowledge of the olfactory region is required to avoid damage to the OE during endoscopic procedures. METHODS: Immunohistochemistry was performed on olfactory mucosa obtained from the unaffected side of olfactory neuroblastoma surgical specimens. The OE was defined as the epithelium containing mature olfactory sensory neurons (OSNs). The distribution and cell kinetics of the OE were examined. RESULTS: The OE was selectively localized to the anterior two-thirds of the superior turbinate (ST) and in the nasal septum (NS) just opposite to the ST; the OE was not detected within the mucosa of the superior meatus. The density of mature OSNs was high at the ethmoid tegmen but gradually decreased with distance from the ethmoid tegmen. The extent of cell death and proliferation was relatively even across the OE. Analysis of airflow profiles revealed that resection of inferior ST does not decrease airflow to the OC. CONCLUSION: The results indicate that the distribution and degree of differentiation of mature OSNs are heterogenous throughout the OE. Epithelial resection of the anterior or superior ST has the potential to damage olfactory function. Resection of the inferior or posterior ST or widening of the superior meatus is a safer alternative that does not damage mature OSNs or alter airflow to the OC.

Management and surgical approach ingenuity for nasal fibro-osseous lesions at our facility: A case series of 15 patients.

To retrospectively evaluate our treatment algorithm and surgical approaches for nasal fibro-osseous lesions at our hospital. Fifteen patients with nasal fibro-osseous lesions treated from January 1, 2010, to January 31, 2020 were included. Among them, 13 patients who underwent surgery were divided into groups A and B, based on whether they were treated before or after the treatment algorithm was established. The extent of the lesion, surgical approach, and outcomes, including bone regrowth assessed postoperatively using computed tomography at 6 months, were analyzed. In group A, six cases were treated via endoscopy and two via a combined endoscopy and external approach. In group B, three cases were treated via endoscopy, one via combined endoscopy and external approach, and one combined with craniotomy. Two group A cases and no group B cases had residual lesions postoperatively. Postoperative bone regrowth occurred in three group A patients and no group B patients. Multi-angled approaches for nasal fibro-osseous lesions based on the unified treatment algorithms used in the study may lead to a reduction in postoperative recurrence and complication rates.

Frontal Sinus "Hump": An Anatomical Risk Factor for Anterior Skull Base Injury in the Endoscopic Modified Lothrop Approach (Outside-In Frontal Drill-Out).

Skull base injuries caused by the outside-in frontal drill-out technique have not been reported. In this report, we chose an outside-in approach to open the frontal sinus for olfactory neuroblastoma resection. Although we identified the first olfactory fibre, the anterior skull base was damaged while drilling into the frontal sinus on the tumour side. We reconstructed the skull base in multiple layers using fascia and cartilage. Postoperative cerebrospinal fluid leakage or intracranial haemorrhage was not observed. In this case, a morphological difference existed in the posterior wall of the frontal sinus between the right and left sides, like a "hump" in the posterior wall of the frontal sinus. This case of damage to the anterior skull base that could not be avoided by identifying the first olfactory fibre alone is the first published case of skull base injury caused by the outside-in approach due to morphological variations of the frontal sinus and skull base. In this approach, the posterior wall of the frontal sinus cannot be observed because the intraoperative landmark is limited to the first olfactory fibre. Therefore, morphological variations of the posterior wall of the frontal sinus should be analysed in advance to prevent cranial base injury.