The importance of the palatine bone for endoscopic endonasal skull base surgery.

Endoscopic endonasal skull base surgery is increasingly prevalent, with its scope expanding from pathogens in the midline region to those in the paramedian region. Maximizing anterior sphenoidectomy is important for the median approach, and lateralizing the pterygopalatine fossa is crucial for the paramedian approach. Maximizing the surgical corridor in the nasal cavity and minimizing damage to neurovascular structures are vital for establishing a surgical field with minimal bleeding, ensuring safe, precise, and gentle procedures. However, the relationship between the maxillofacial and skull base bones in endoscopic endonasal skull base surgery is difficult to understand because these bones are intricately articulated, making it challenging to visualize each bone's outline. Understanding important bones and their related neurovascular structures is essential for all skull base surgeons to maximize the surgical corridor and minimize iatrogenic injury to neurovascular structures. This study aimed to elucidate the role of the palatine bone from a microsurgical anatomical perspective. Three dry skulls were used to demonstrate the structure of the palatine bone and its relationship with surrounding bones. A formalin-perfused cadaveric head was dissected to show the related neurovascular structures. The arteries and veins of the cadaveric heads were injected with red- and blue-colored silicon. Dissection was performed using a surgical microscope and endoscope. In addition, the utilization of the palatine bone as a landmark to identify neurovascular structures, which aids in creating a wider surgical field with less bleeding, was shown in two representative cases. The palatine bone consists of unique complex structures, including the sphenoidal process, ethmoidal crest, pterygopalatine canal, and sphenopalatine notch, which are closely related to the sphenopalatine artery, maxillary nerve, and its branches. The ethmoidal crest of the palatine bone is a well-known structure that is useful for identifying the sphenopalatine foramen, controlling the sphenopalatine artery and nerve, and safely opening the pterygopalatine fossa. The sphenoidal process of the palatine bone is a valuable landmark for identifying the palatovaginal artery, which is a landmark used to safely and efficiently expose the vidian canal. The sphenoidal process is easily cracked with an osteotome and removed to expose the palatovaginal artery, which runs along the pharyngeal groove, just medial to the vidian canal. By opening the pterygopalatine canal (also known as the greater palatine canal), further lateralization of the periosteum-covered pterygopalatine fossa contents can be achieved. Overall, the sphenoidal process and ethmoidal crest can be used as important landmarks to maximize the surgical corridor and minimize unnecessary injury to neurovascular structures.

Takedown and Reuse of a Posterior Septal Nasal Floor Mucosal Flap for Skull Base Reconstruction in a Revision Surgery for a Recurrent Pituitary Tumor.

Various types of mucosal flaps can be used for skull base reconstruction after endoscopic endonasal skull base surgery (EESS). Preventing postoperative cerebrospinal fluid (CSF) leakage is essential. Flap creation during revision surgery can be problematic. We present a patient in whom a posterior septal nasal floor flap (PS-NF) was successfully reused for reconstruction after multiple reoperations for pituitary tumor resection. A 22-year-old female underwent EESS for resection of a pituitary tumor and experienced multiple recurrences after repeated operations. For the third recurrence, a skull base surgery team comprising otolaryngologists and neurosurgeons performed a binostril combined transnasal/transseptal approach and used a PS-NF for reconstruction. For the fourth recurrence, a PS-NF was successfully taken down and reused for reconstruction. No postoperative CSF leakage or intranasal complications occurred. Skull base reconstruction using a PS-NF is feasible and preserves the mucous membrane of the nasal septum and the morphology of the nasal cavity. PS-NF takedown and reuse is an option for revision EESS for recurrent pituitary tumors.

The sphenopalatine vein: anatomical study of a rarely described structure.

Although in counterpart, the sphenopalatine artery (SPA), has been well described in the medical literature, the sphenopalatine vein (SPV) has received scant attention. Therefore, the present anatomical study was performed. Additionally, we discuss the variations, embryology, and clinical significance of the SPV. Adult cadaveric specimens underwent dissection of the SPV. In addition, some specimens were submitted for histological analysis of this structure. The SPV was found to drain from the sphenoidal sinus and nasal septum. Small tributaries traveled through the nasal septum with the posterior septal branches of the SPA and nasopalatine nerve. The SPA and SPV were found to travel through the sphenopalatine foramen and another tributary was found to perforate the medial plate of the pterygoid process and to connect to the pterygoid venous plexus which traveled lateral to the medial plate of the pterygoid process. The vein traveled through the posterior part of the lateral wall of the nasal cavity with the posterior lateral nasal branches of the SPA and the lateral superior posterior nasal branches of the maxillary nerve. To our knowledge, this is the first anatomical study on the SPV in humans. Data on the SPV provides an improved anatomical understanding of the vascular network of the nasal cavity. Developing a more complete picture of the nasal cavity and its venous supply might help surgeons and clinicians better manage clinical entities such as posterior epistaxis, cavernous sinus infections, and perform endoscopic surgery with fewer complications.

Human papillomavirus-related multiphenotypic sinonasal carcinoma: A report of two patients and review of the literature.

Human papillomavirus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC) is a recently described sinonasal tract tumor that is associated with high-risk HPV subtype infection. Despite histological features that are suggestive of a high-grade malignant tumor, the prognosis of HMSC is relatively good; however, the clinical features of this tumor are poorly understood. Here, we describe two patients with HMSC. The first was initially diagnosed with adenoid cystic carcinoma of the right nasal cavity; the tumor was extirpated via endoscopic endonasal surgery. Seventy-four months later, the tumor recurred in the right inferior turbinate and was diagnosed as HMSC after biopsy, whereupon it was resected en block via endoscopic endonasal surgery. No adjuvant therapy was administered during either episode; moreover, no recurrences have occurred during the 44 months since the second operation. The second patient was diagnosed with HMSC based on the biopsy of the tumor occupying the left nasal cavity. The tumor was completely resected under endoscopic endonasal surgery, and no adjuvant therapy was administered. There has been no recurrence for 15 months after the operation. Herein, we also review the clinical features of this tumor type based on 69 previously reported cases as well as our patients.

Endonasal endoscopic surgery for temporal lobe epilepsy associated with sphenoidal encephalocele.

BACKGROUND: Temporal lobe epilepsy (TLE) associated with temporal lobe encephalocele is rare, and the precise epileptogenic mechanisms and surgical strategies for such cases are still unknown. Although the previous studies have reported good seizure outcomes following chronic subdural electrode recording through invasive craniotomy, only few studies have reported successful epilepsy surgery through endoscopic endonasal lesionectomy. CASE DESCRIPTION: An 18-year-old man developed generalized convulsions at the age of 15 years. Despite treatment with optimal doses of antiepileptic drugs, episodes of speech and reading difficulties were observed 2-3 times per week. Long-term video electroencephalogram (EEG) revealed ictal activities starting from the left anterior temporal region. Magnetic resonance imaging revealed a temporal lobe encephalocele in the left lateral fossa of the sphenoidal sinus (sphenoidal encephalocele). Through the endoscopic endonasal approach, the tip of the encephalocele was exposed. A depth electrode was inserted into the encephalocele, which showed frequent spikes superimposed with high-frequency oscillations (HFOs) suggesting intrinsic epileptogenicity. The encephalocele was resected 8 mm from the tip. Twelve months postoperatively, the patient had no recurrence of seizures on tapering of the medication. CONCLUSION: TLE associated with sphenoidal encephalocele could be controlled with endoscopic endonasal lesionectomy, after confirming the high epileptogenicity with analysis of HFOs of intraoperative EEG recorded using an intralesional depth electrode.

Optimal Management of the Unilateral Recurrent Laryngeal Nerve Involvement in Patients with Thyroid Cancer.

We aimed to determine the optimal management of recurrent laryngeal nerve (RLN) involvement in thyroid cancer. We enrolled 80 patients with unilateral RLN involvement in thyroid cancer between 2000 and 2016. Eleven patients with preoperatively functional vocal folds (VFs) underwent sharp tumor resection to preserve the RLN (shaving group). Thirty-three patients underwent RLN reconstruction with RLN resection (reconstruction group). We divided the reconstruction group into two subgroups based on preoperative VF mobility (normal-reconstruction and paralyzed-reconstruction subgroups). In the cases where RLN reconstruction was difficult, phonosurgeries including arytenoid adduction (AA), with or without thyroplasty type I, or nerve muscle pedicle implantation with AA were performed later (phonosurgery group). We evaluated and compared vocal function among the evaluated periods and different groups. Postoperative vocal function in the shaving and normal-reconstruction subgroups was favorable. There were no significant differences between the two groups. In the paralyzed-reconstruction and phonosurgery groups, postoperative vocal function was significantly improved, and vocal function in the paralyzed-reconstruction subgroup was significantly better than that in the phonosurgery group. For optimal management of unilateral RLN involvement in thyroid cancer, first, sharp dissection should be performed, and if this is impossible, a simultaneous RLN reconstruction procedure should be adopted whenever possible.

A Pedicled Posterior Septal-Nasal Floor Flap and a Novel Rescue Flap for Skull Base Reconstruction.

OBJECTIVE: We devised a new surgical alternative to the conventional nasoseptal flap, a pedicled posterior septal-nasal floor flap that we named the Kegon flap. We evaluated the effectiveness of this flap for skull base reconstruction in patients with high-flow cerebrospinal fluid (CSF) leakage after sellar/parasellar tumor resection. METHODS: The Kegon flap with a novel rescue flap was designed to preserve blood flow and mucosa anterior to the nasal septum and to avoid flap damage during surgery. We retrospectively evaluated postoperative flap perfusion with T1-weighted contrast-enhanced magnetic resonance imaging and characterized complications and wound healing in 5 patients who experienced high-flow CSF leakage after sellar/parasellar tumor resection requiring reconstruction. RESULTS: Postoperative T1-weighted contrast-enhanced magnetic resonance imaging demonstrated good flap perfusion in all patients. The area reconstructed with the Kegon flap healed within the first month following surgery. No postoperative CSF leakage or nasal hemorrhage was observed. There was no perforation of the anterior nasal septum after surgery. The mucosal defect had completely epithelialized in all patients by 3 months after surgery. There were no instances of prolonged nasal crusting or any subjective decrease in olfactory function 3 months after surgery. CONCLUSIONS: The use of a Kegon flap with a novel rescue flap was effective and helped preserve nasal structure and function in patients undergoing skull base reconstruction after sellar/parasellar tumor resection associated with high-flow CSF leakage.

Treatment Outcomes of Pulmonary Metastases from Head and Neck Squamous Cell Carcinoma.

Although the lung is the most common site of distant metastases from head and neck squamous cell carcinoma (HNSCC), the number of reports about the effects of pulmonary metastasectomy for the treatment of lung metastasis from HNSCC is limited. Metachronous pulmonary metastases were detected in 45 HNSCC patients at Kumamoto University Hospital from 1998 to 2018. Twenty-two patients underwent an operative resection (Ope group) and 23 underwent chemotherapy (Chemo group). The 3-year overall survival (OS) rate and median OS were evaluated. The effects of adjuvant chemotherapy after pulmonary metastasectomy and of new drugs (cetuximab and nivolumab), in the chemo group were also assessed. The 3-year OS rates and median OS were: Ope, 66.1% and 31.5 months; Chemo, 39.7% and 18 months, respectively. In the Ope group, addi-tional recurrences were significantly fewer in the patients who underwent adjuvant chemotherapy post-surgery versus the patients who underwent surgery alone (p = 0.013). In the Chemo group, the 3-year OS rate of the patients who received new drugs was significantly better than that of the patients who did not (p = 0.021). Adjuvant chemotherapy after pulmonary metastasectomy may be a preferable treatment option for preventing recurrences. Cetuximab and nivolumab have a potential to improve OS.

Long-term effectiveness, safety, and quality of life outcomes following endoscopic posterior nasal neurectomy with submucosal turbinectomy for the treatment of intractable severe chronic rhinitis.

OBJECTIVE: In recent decades, posterior nasal neurectomy (PNN) with submucosal inferior turbinectomy (ST) has been increasingly used for the treatment of intractable severe rhinitis; however, to the best of our knowledge, there have been few studies regarding its long-term therapeutic effects or its influence on patient quality of life (QOL). Therefore, this study examined the long-term therapeutic effects in patients who underwent PNN with ST, as well as their QOL and medication use after surgery. METHODS: This retrospective cohort study initially included 16 consecutive patients who underwent PNN with ST from January 2010 to December 2011. Ten of the 16 patients participated in a paper-based survey questionnaire between June 2018 and November 2018; the responses of these 10 patients were used for analysis in this study. To clarify the effects of surgical treatment on symptoms, QOL, and medication status, data recorded before and 3 months after surgery were compared with data recorded at 8 years after surgery using the Japan Rhinoconjunctivitis Quality of Life Questionnaire No. 1 and Classification of the Severity of Allergic Rhinitis Symptoms I and II. RESULTS: Nasal symptoms including runny nose and nasal congestion, medication score, respective total symptoms medication scores (i.e., combined average total symptoms score and medication score), and the scores of troubles with daily life and total QOL were significantly improved at 3 months and 8 years after surgery, compared with before surgery; scores were not significantly worsened at 8 years after surgery, compared with 3 months after surgery. In addition, there were no adverse events requiring treatment after surgery. CONCLUSION: Our findings suggest that PNN with ST is effective and safe for long-term treatment of severe chronic rhinitis symptoms, as well as reduction of medication use and improvement of QOL.

Clinicopathological analysis of sinonasal malignant lymphoma in an HTLV-1 endemic area in Japan -special focus on primary sinonasal diffuse large B-cell lymphoma.

The present study investigated histological subtypes of lymphoma in patients newly diagnosed with malignant lymphoma in the human T-cell leukemia virus type 1 (HTLV-1) endemic area of Japan, and further analyzed the clinicopathological features and clinical outcomes of patients with primary sinonasal lymphoma. We retrospectively examined 151 patients aged 18-90 years in Fukuoka, Japan. Subtypes of lymphoma were determined according to the WHO classification. Among the 151 patients, 104 were diagnosed with malignant lymphoma, including 96 at the time of initial diagnosis. Ninety-two of the 96 lymphomas (96%) were non-Hodgkin lymphoma. Mature B-cell neoplasms comprised 78% (n = 75). Primary lymphoma of the sinonasal cavity was found in six patients (6%). The histological subtype of sinonasal lymphoma was diffuse large B-cell lymphoma (DLBCL) in all six tumors. Furthermore, overall survival was significantly different among three distinct DLBCL patient groups, including primary sinonasal lymphoma patients (p = 0.0016; 3-year overall survival: sinonasal DLBCL group, 53%; DLBCL of the CNS group, 0%; other DLBCL group, 83%). Our study suggests that primary DLBCL of the sinonasal tract is a distinct disease entity of DLBCL.

Radiation exposure to general public after permanent brachytherapy for prostate cancer.

Permanent prostate brachytherapy patients are generally told to limit their time around children and pregnant women. However, there is little data available to validate the instruction. For the skin effective dose rate, ion chamber survey meter model 451B-DE-SI was used. The meter was scanned at the point of 4.5, 20, 50 and 100 cm from the skin surface in each plane. Life time exposure was calculated from the average anterior data. At the point of 4.5 cm from the anterior skin surface, the lifetime equivalent dose was 46.5 mSv, at 20 cm it was 13.2 mSv, at 50 cm it was 3.5 mSv and at 100 cm it was 0.9 mSv. The risk from the prostate brachytherapy patients to general public is quite low. Only the case of close and long-time contact with the pregnant and the infant should be paid attention to.