[in Japanese]

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[in Japanese]

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[in Japanese]

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[in Japanese]

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Phonosurgery encompasses a range of surgical procedures aimed at improving voice function, and is broadly categorized into endolaryngeal microsurgery, endoscopic laryngeal surgery, and laryngeal framework surgery. This review outlines the indications, surgical techniques, and clinical outcomes associated with each type. For benign vocal fold lesions such as polyps, Reinke’s edema, and cysts, microsurgical excision under general anesthesia has demonstrated favorable improvements in voice parameters. In Reinke’s edema, a potential role of hypoxia-inducible factor-1α and vascular endothelial growth factor in the pathogenesis has been identified. Vocal fold cysts treated with microflap dissection also showed significant voice improvement across multiple acoustic and aerodynamic parameters.
For laryngeal stenosis, the use of silicone tube stents for the patient with anterior glottic web and endoscopic wedge excision using CO₂ lasers for a patient with subglottic stenosis or supraglottic stenosis were effective in maintaining vocal function while minimizing invasiveness. CO₂ laser surgery has also proven useful in treating early-stage laryngeal and hypopharyngeal cancer. Vocal fold paralysis or atrophy is commonly treated with injection laryngoplasty, including autologous fat, and may also benefit from type I thyroplasty. Long-term voice outcomes are generally favorable, especially with adequate injection volume in male patients.
Laryngeal framework surgery is employed not only for unilateral vocal fold paralysis, but also for pitch modulation and spasmodic dysphonia. Furthermore, cartilage repair in cases of laryngeal trauma has shown promising results in restoring vocal function. This comprehensive review highlights the current advances and effective strategies in phonosurgery, contributing to improved voice quality and patient outcomes.

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A retrospective review was conducted on 43 patients with primary hyperparathyroidism who underwent surgery at our hospital between 2015 and 2022 to identify predictors of postoperative tetany. Postoperative tetany was observed in 5 cases. Statistical analysis of the relationship between postoperative tetany and preoperative serum Ca, i-PTH, BUN, ALP, P, amount of Ca decline, surgical time, tumor size, menopausal status, and clinical type revealed that the risk of postoperative tetany was significantly higher in patients with nephrolithiasis or a combination of nephrolithiasis and bone disease, compared to those with hypercalcemia or bone disease alone. This is believed to be due to prolonged bone resorption in patients with nephrolithiasis or both nephrolithiasis and bone disease, which is rapidly corrected after surgery, making these patients more susceptible to developing tetany.

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Head and neck neuroendocrine carcinoma is a relatively rare disease, and there are few consolidated reports in Japan. We investigated 15 cases of head and neck neuroendocrine carcinoma treated at our department. The most common site was the nasal cavity and paranasal sinuses, with 6 cases （40％）, followed by the supraglottis with 5 cases （33％）. At the time of initial consultation, cervical lymph node metastasis was observed in 5 cases （33％）, and distant metastasis was found in 4 cases （27％）. The 5-year overall survival （OS） for all cases was 40％, disease-specific survival （DSS） was 44％, and disease-free survival （DFS） was 32％. There was no significant difference in prognosis based on the tumor site. However, patients with cervical lymph node metastasis or distant metastasis had a poorer prognosis. In cases where surgical resection is possible, postoperative chemotherapy or radiotherapy is considered when cervical lymph node metastasis is present. INSM-1 is suggested to be a useful marker for the diagnosis of head and neck neuroendocrine tumors.

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We have devised a surgical method to perform transcanal endoscopic mastoidectomy with AR support for patients with poor mastoid pneumatization. This procedure does not require a retroauricular incision, and we call it Image-Guided Transcanal Endoscopic Mastoidectomy （IGTEM）. We report 10 cases in which this procedure was performed. The indications for this procedure include intratemporal lesions in cases of poor mastoid air cells. With the assistance of medical devices such as endoscopes, powered devices, and AR navigation, it may be possible to complete mastoid antrum and mastoid air cell procedures less invasively and more safely, even in cases where conventional surgical procedures are challenging.

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Preoperative cytological diagnosis is not recommended due to the risk of metastasis, so preoperative diagnosis based on clinical findings is important. To confirm the usefulness of preoperative predictors for the diagnosis of malignant parathyroid tumors, we performed a statistical analysis of 50 cases of parathyroid carcinoma and 65 cases of parathyroid adenoma. In the multivariate analysis, significant differences were found in the following four items: corrected Ca＞12.75mg/dl, intact PTH＞390pg/ml, tumor D/W ratio＞1.07, and tumor compressing the thyroid gland or penetrating into the thyroid gland. Sensitivity of 74％ and specificity of 95％ were observed for the presence of parathyroid carcinoma when any two or more of the above items were positive. The Youden index was the highest at 0.69, which seemed to be useful for the diagnosis of parathyroid carcinoma.

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We reviewed the data of 34 patients with deep cervical abscesses who were treated with incision and drainage under general anesthesia at our institution. Among the 34 patients, 28 were discharged, 2 were transferred for rehabilitation, 3 died, and 1 remained in a vegetative state preoperatively. Nasogastric tubes were placed in 28 patients; however, 5 could not regain oral intake and remained dependent on enteral nutrition throughout hospitalization. Two patients were classified as extremely high risk based on the preoperative Charlson comorbidity index, and both died postoperatively. Patients with abscesses extending below the hyoid bone on preoperative computed tomography were less likely to have their nasogastric tubes removed. Appropriate surgical drainage, early evaluation of swallowing function, swallowing rehabilitation, and preoperative risk assessment are essential for achieving optimal outcomes in the treatment of deep neck abscesses.

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We have proposed a 6-cm small skin incision for supracricoid partial laryngectomy （SCPL）. This small incision approach was clinically introduced to SCPL in 2019 and to total laryngectomy （TL） in 2022. We reviewed 18 patients who were operated by the small incision approach in the past three years （2022-2024）. There were 10, 7, and 1 patients who received SCPL, TL, and partial laryngopharyngectomy, respectively. There were 7 patients who received surgeries after failed radiation therapy. The average duration of hospitalization was 30 days in the SCPL group. TL patients started oral diet after videofluoroscopic examination on average at 8.2 days after surgery. Additional experience is needed to elucidate the usefulness of the 6-cm small incision approach.

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We conducted a retrospective study focusing on 28 non-surgical cases among 154 patients with salivary gland carcinoma treated in our department between 1999 and 2024. The primary tumor sites were the parotid gland in 22 cases and the submandibular gland in 6 cases. The non-surgical group had a significantly worse prognosis compared to the surgical group （5-year overall survival rate: surgical group 85.7％ vs. non-surgical group 25.7％, p＜0.001）. The non-surgical group was classified into four subgroups based on treatment modality: definitive radiotherapy group （n＝13）, chemotherapy group （n＝3）, palliative radiotherapy group （n＝3）, and non-intervention group （n＝8）. Prognosis was analyzed for each group. The 5-year overall survival rates were 35.6％ in the definitive radiotherapy group, 33.3％ in the chemotherapy group, and 0％ in both the palliative radiotherapy and non-intervention groups. Personalized medicine based on therapeutic target molecules is expected to play a key role in improving prognosis in the future.

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We investigated the prognosis and occurrence of double cancers in patients with primary squamous cell carcinoma of the maxillary sinus （SCC-MS） who underwent initial treatment at our department. The 3-year survival rate of all 38 patients was 75.0％ （81.4％ in the first surgery group and 77.9％ in the RADPLAT group）. When SCC-MS was considered the primary cancer, 6 patients had double cancers, and including patients with cancer before SCC-MS, a total of 9 patients had complications of other carcinomas. Under the concept of field cancerization, it is necessary to continue to carefully follow up patients with SCC-MS and other head and neck cancers for recurrence and the occurrence of multiple cancers.

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Primary rhabdomyosarcoma of the nasal sinus is relatively rare, and particle therapy is often used for local treatment. There are scattered reports of proton therapy, but very few reports of carbon-ion radiotherapy. We report two cases of adult alveolar rhabdomyosarcoma of the nasal sinus treated with carbon-ion radiotherapy. The first case was a 67-year-old female, and the second case was a 53-year-old female. Both patients had local remnants or recurrence after prior chemotherapy and were treated with carbon-ion radiotherapy. Due to metastatic growth outside the irradiated area, they died of the primary disease 2.5 years and 6 months after the carbon-ion radiotherapy, respectively. In both cases, there was no recurrence in the irradiated field, and local control was good, leading to improvement in subjective symptoms. Carbon-ion radiotherapy is considered an effective local treatment option for rhabdomyosarcoma.

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Introduction: Laryngeal stenosis can be caused by iatrogenic, traumatic or idiopathic reasons, and can cause dyspnea and hoarseness. In 2020, Ekbom et al. devised the endoscopic wedge excision （EWE） for subglottic stenosis and reported its efficacy. In this study, we report two cases of laryngeal stenosis that were successfully treated with EWE.
Case 1: A 15-year-old male. He was endotracheally intubated for croup syndrome in infancy and subsequently underwent tracheostomy due to subglottic stenosis. He requested cannula-free tracheostomy, and EWE was performed. Six months after surgery, mild stenosis was observed, but there was no dyspnea. Therefore, tracheocutaneous fistula closure was performed.
Case 2: A 73-year-old woman. She presented to our department with dyspnea and dysphonia without any triggers. Laryngeal endoscopic examination revealed a circumferential stenosis of the laryngeal vestibule. After tracheostomy, EWE was performed. There was no postoperative restenosis, and tracheocutaneous fistula closure was performed 2 months after EWE. The patient is still alive without recurrence.
Discussion: EWE is a technique in which the stenosis is divided into three or four wedge-shaped sections by CO2 laser and a narrow bridge is left between each section. Compared to conventional endoscopic balloon dilation or cricotracheal resection for subglottic stenosis, EWE is less likely to cause postoperative restenosis or voice disorders. In this case, EWE was also performed for supraglottic stenosis, and good results were obtained. Therefore, it is suggested that EWE is an effective technique for supraglottic stenosis.
Conclusion: We experienced two cases of laryngeal stenosis that were successfully treated with EWE. This technique is less likely to cause postoperative restenosis or voice disorders, and is effective not only for subglottic stenosis but also for supraglottic stenosis.

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We present a case of non-occlusive mesenteric ischemia （NOMI） that developed after surgery for recurrent hypopharyngeal cancer in a 73-year-old male patient with multiple comorbidities. The patient had a history of radiation therapy for hypopharyngeal cancer （cT2N0M0） at age 71 and was diagnosed at age 73 with a local recurrence and a newly identified tongue cancer （cT1N0M0）. Due to chronic renal failure requiring hemodialysis and other complications, a limited surgical approach was selected. The patient underwent total pharyngo-laryngo-esophagectomy without reconstruction, and partial tongue resection. Enteral nutrition was initiated on postoperative day one, and hemodialysis was resumed on day two. On postoperative day three, the patient developed severe abdominal pain, and contrast-enhanced CT confirmed a diagnosis of NOMI. Emergency surgery, including partial resection of the colon and small intestine with stoma creation, was performed. Despite these interventions, the patient experienced recurrent abdominal pain on postoperative day ten, and CT findings suggested residual intestinal necrosis. Further surgical intervention was deemed unfeasible, and despite ongoing conservative management, the patient succumbed to the condition on postoperative day eleven. This case highlights the challenges of managing NOMI, particularly in patients with multiple risk factors such as advanced age, cardiovascular disease, chronic renal failure, and recent major surgery. The rapid progression and poor prognosis emphasize the critical importance of early recognition and intervention in NOMI cases, especially in high-risk surgical patients.

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We encountered a case of carotid blowout syndrome （CBS） as a complication of postoperative adjuvant chemoradiotherapy for advanced tongue cancer. The patient, a 56-year-old male, underwent primary tumor resection, followed by postoperative adjuvant chemoradiotherapy for tongue cancer （cT4aN3bM0）. One month after treatment completion, he developed mandibular osteomyelitis, followed by CBS two months later. Emergency endovascular treatment, including internal carotid artery stent graft placement and embolization of the external carotid artery, successfully achieved hemostasis. CBS is a severe complication associated with head and neck cancer treatment and can be fatal without prompt diagnosis and intervention. Recently, endovascular treatment has been used occasionally as a primary treatment option. Determining the appropriate indications for endovascular treatment is crucial for treatment selection.

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A 64-year-old woman visited our hospital complaining of an infra-auricular mass. The mass had been present for about 20 years and had recently increased in size. There were no signs suggestive of malignancy, such as pain/tenderness, adhesions to surrounding tissues, or facial nerve paralysis. Magnetic resonance imaging and ultrasound revealed internal heterogeneity of the tumor, suggesting malignancy. Fine needle aspiration cytology suggested a low- to intermediate-grade malignant carcinoma. Surgery was performed under general anesthesia. The tumor was located in the deep lobe and was adherent to the marginal mandibular and buccal branches of the facial nerve. The nerve branches were resected, and lobectomy of the superficial and lower half of the parotid gland was performed. Frozen section findings indicated a low- to intermediate-grade malignant carcinoma, with no apparent lymph node metastasis. The facial nerve was reconstructed using the great auricular nerve. Histopathological examination, including various immunohistochemical stains, revealed intraductal carcinoma. Postoperatively, there was paralysis of the lower lip but no paralysis in other areas. The postoperative course was uneventful, and the patient was discharged on the fourth postoperative day. Final pathological examination revealed intraductal carcinoma, which is considered a low-grade malignancy. Because resection was sufficient and there was no lymphatic invasion, postoperative radiation was not performed. At six months postoperatively, no definitive evidence of recurrence has been observed. Intraductal carcinoma is a rare disease; further cases need to be accumulated. It is classified as low-grade malignant carcinoma, and the prognosis and treatment of parotid carcinoma differ between low- to intermediate-grade and high-grade malignancies. Accordingly, assessment of malignancy grade through physical examination, imaging, fine needle aspiration cytology, and frozen section biopsy is essential for guiding appropriate treatment.

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Neurofibromatosis type 1 （NF1） is an autosomal dominant disorder, which affects approximately 40,000 people in Japan, and is known to be associated with a variety of lesions in organs throughout the body, including café-au-lait spots and schwannomas. In this report, we describe a case of NF1 with a large malignant vagal schwannoma. A 36-year-old male was referred to our department because of a hard mass in the right anterior neck region. Imaging examination revealed a tumor with a diameter of 50mm, which was located between the right internal jugular vein and the right common carotid artery, and endoscope revealed paralysis of the right vocal cord. Clinically, malignant vagal nerve schwannoma was suspected, but fine-needle aspiration cytology and needle biopsy could not confirm the diagnosis. Surgical resection was performed for diagnostic treatment, and the diagnosis of malignant vagal schwannoma was confirmed by postoperative pathological examination. Since the resection was complete with negative margins, no postoperative treatment was performed. The patient was followed postoperatively without recurrence for ten months.

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Juvenile nasopharyngeal angiofibroma （JNA） is a benign tumor that predominantly affects adolescent males, and surgical resection is the treatment of choice. However, due to its abundant vascularity and local invasiveness, surgery is often technically challenging. We report a case of a 14-year-old male with Radkowski stage ⅢA JNA who underwent successful en bloc resection following preoperative arterial embolization. The tumor was removed via an endoscopic tri-port approach, combining transseptal access with crossing multiple incisions （TACMI）, endoscopic modified medial maxillectomy （EMMM）, and a direct approach to the anterior and lateral parts of the maxillary sinus （DALMA）. This technique enabled wide access to the lesion while preserving nasal function and minimizing invasiveness. A vessel sealing device （BiZact^TM） was effectively used during resection to achieve hemostasis and facilitate safe dissection in highly vascularized areas.

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Combination therapy with Dabrafenib and Trametinib may represent a promising treatment option for unresectable locally advanced thyroid carcinoma. We report two cases of BRAF V600E-mutated differentiated thyroid carcinoma with suspected invasion of the airway lumen and the common carotid artery, in which this therapy was introduced. Case 1 was a 75-year-old man with papillary thyroid carcinoma exhibiting significant tracheal invasion. Tumor reduction following treatment led to relief of airway stenosis. Case 2 was a 76-year-old woman with recurrent papillary thyroid carcinoma filling the subglottic space. Tumor reduction resulted in improvement of vocal function. Advances in systemic therapy are expected to further enhance treatment strategies for locally advanced thyroid carcinoma.

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Rupture of an inferior thyroid artery aneurysm is extremely rare, with only approximately 30 cases reported in the literature since the first description in 1959. Despite its rarity, it should be considered in the differential diagnosis of acute neck swelling and respiratory distress, as it may present suddenly and progress to a life-threatening condition. We report a case of a 32-year-old man with a history of Basedow’s disease who presented to the emergency department with acute right-sided neck swelling and difficulty of breathing. Laboratory findings showed no signs of infection, and contrast-enhanced computed tomography （CT） demonstrated abnormal soft tissue density extending from the retropharyngeal space to the upper mediastinum. Although no obvious extravasation was initially observed, CT angiography with three-dimensional reconstruction of cervical arteries revealed a spindle-shaped aneurysm, measuring 7×5mm, arising from the right inferior thyroid artery, which was diagnosed as ruptured. The aneurysm was surgically resected, and the patient recovered without recurrence during one year of follow-up. The mechanisms underlying the formation and rupture of such aneurysms remain unclear, and no consistent patient backgrounds or risk factors have been established. Since rupture can sometimes lead to hemodynamic instability, early imaging assessment and accurate diagnosis are essential for selecting appropriate treatment strategies. This case illustrates that prompt identification and surgical intervention can result in favorable outcomes even in rare vascular emergencies. Further case accumulation and analysis are necessary to better understand the pathophysiology and optimal management of this uncommon condition.

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The most common type of pharyngeal foreign body is a fish bone, which penetrates the palatine tonsil. If the foreign body can be seen with the naked eye or endoscope, it is relatively easy to remove, but if it is embedded, a CT scan may be required to identify it. Furthermore, swelling of the larynx may occur, and emergency airway management such as tracheotomy may be required. We report a case of a fish bone foreign body in the palatine tonsil in an elderly woman with a history of thrombocytopenia who underwent tracheotomy and foreign body removal surgery under general anesthesia.

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Keratitis ichthyosis deafness （KID） syndrome is a congenital disorder characterized by ichthyosiform erythroderma, keratitis, and sensorineural hearing loss. The skin is highly susceptible to infection, often leading to severe recurrent infections. The patient was a 23-year-old female who had been treated for many years at a previous facility for KID syndrome. She presented with oral pain, and further evaluation at the previous facility had led to a diagnosis of mandibular gingival carcinoma. Due to KID syndrome, curative treatment for gingival cancer was judged to be difficult, and she was referred to our department. After consultation with the relevant departments, we decided to perform right mandibular segmental resection, right neck dissection, and reconstruction using a free rectus abdominis musculocutaneous flap. The postoperative course was uneventful with no signs of infection or delayed wound healing. She was discharged on postoperative day 21 and has been alive for 8 months without recurrence. Although KID syndrome presents severe skin symptoms, a favorable outcome can be achieved even in cases of advanced surgery with appropriate infection control, since patients are not in a systemic immunocompromised state.

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We present a case of an 11-year-old male patient of East Asian descent with a history of Kimura’s disease. He and his family noticed a swelling and pruritic rash on the right neck at age 9. A biopsy of the right neck lymph node led to the diagnosis of Kimura’s disease at age 11. Anti-histamines, Th2 cytokine inhibitor, and leukotriene receptor inhibitor were prescribed, but had no effect. Steroid therapy was administered when the patient was 19 years old, but it showed limited effect. Owing to the ineffectiveness of these past treatments, the decision was made to perform surgery. The surgery consisted of three steps. The first surgery removed the lymph node-like lesion in the right retro-auricular, posterior neck, and a part of the posterior lesion of the right parotid gland while leaving the tissue surrounding the facial nerve trunk intact. The second surgery was performed eight months after the first surgery, and involved a superficial lobectomy of the right parotid gland and removal of the surrounding lymph node-like lesion. The third surgery was performed one year and 3 months after the first surgery. The lymph node-like lesion in the left retro-auricular, posterior neck, and a part of the posterior lesion of the left parotid gland were removed while leaving the tissue surrounding the facial nerve trunk intact. Care was taken not to damage the facial nerve branches while also duly considering the cosmetic results. The difference between the appearance of the right and left side of the face was able to be minimized. One year and two months have passed after the third surgery, reduction of the surgical legions is maintained, and the patient and his family are satisfied with the appearance. Moreover, the blood eosinophil count and IgE level are lower after the surgeries. Therefore, we consider that we successfully controlled the state of this disease by surgeries.

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Synovial sarcoma is a malignant soft tissue tumor that commonly occurs in young people, and curability and preserving function are critical issues in the head and neck region. We present a case of a 10-year-old male who had pediatric oropharyngeal synovial sarcoma. The tumor was localized to the right lateral wall of the oropharynx and was diagnosed as synovial sarcoma by histopathology and genetic examination. The patient was treated with induction chemotherapy followed by proton beam therapy. After radiation, the tumor shrank, but remained, and so the patient was referred to our department for surgical intervention. A total pharyngolaryngo-esophagectomy was planned, but resulted in partial resection of the oro- and hypopharynx, bilateral neck dissection, and reconstruction with a free jejunal patch. Four years after the surgery, there is no evidence of recurrence, and the patient is able to take school meals with continuous swallowing therapy. This surgical procedure successfully removed the tumor and preserved function, allowing the patient to return to school life.

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There are two types of surgical removal for dermoid cysts of the floor of the mouth: the intraoral approach and the transcervical approach. Intraoral resection has great cosmetic advantages, but it is sometimes difficult because of poor visibility. We report the case of dermoid cyst of the floor of the mouth in a 10-year-old boy. MRI examination suggested a sublingual dermoid cyst, so we decided to remove it via an intraoral approach. We performed endoscope-assisted intraoral resection with a good view of the lesion, and succeeded in completely removing the cyst without causing cyst rupture. Endoscope-assisted intraoral resection for dermoid cysts of the floor of the mouth is considered to be a useful method that can be performed safely with a good view of the lesion and may reduce the risk of postoperative complications and recurrence.

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We performed endoscopic laryngopharyngeal surgery （ELPS） using the underwater method in three cases of posterior hypopharyngeal cancer. The underwater technique provided a clear field of view without bubbles or halation, with a 1.33-fold magnification. No complications or dysphagia were observed. Further research is needed to assess its impact on resection speed and completeness.

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