Takashi Anzai

A feasibility study of NIR fluorescent image-guided surgery in head and neck cancer based on the assessment of optimum surgical time as revealed through dynamic imaging

Background In order to minimize surgical stress and preserve organs, endoscopic or robotic surgery is often performed when conducting head and neck surgery. However, it is impossible to physically touch tumors or to observe diffusely invaded deep organs through the procedure of endoscopic or robotic surgery. In order to visualize and safely resect tumors even in these cases, we propose using an indocyanine green (ICG) fluorescence method for navigation surgery in head and neck cancer. Objective To determine the optimum surgical time for tumor resection after the administration of ICG based on the investigation of dynamic ICG fluorescence imaging. Methods Nine patients underwent dynamic ICG fluorescence imaging for 360 minutes, assessing tumor visibility at 10, 30, 60, 120, 180, and 360 minutes. All cases were scored according to near-infrared (NIR) fluorescence imaging visibility scored from 0 to 5. Results Dynamic NIR fluorescence imaging under the HyperEye Medical System indicated that the greatest contrast in fluorescent images between tumor and normal tissue could be observed from 30 minutes to 1 hour after the administration of ICG. The optimum surgical time was determined to be between 30 minutes to 2 hours after ICG injection. These findings are particularly useful for detection and safe resection of tumors invading the parapharyngeal space. Conclusion ICG fluorescence imaging is effective for the detection of head and neck cancer. Preliminary findings suggest that the optimum timing for surgery is from 30 minutes to 2 hours after the ICG injection.

Significant preservation of swallowing function in chemoradiotherapy for advanced head and neck cancer by prophylactic swallowing exercise

Dysphagia is a serious complication of chemoradiotherapy (CRT) in patients with head and neck cancer. Approximately 20% to 30% of patients who have dysphagia require feeding tubes. The purpose of this study was to evaluate the impact of prophylactic swallowing exercises on swallowing function.

Impact of intra-arterial chemotherapy including internal carotid artery for advanced paranasal sinus cancers involving the skull base

Background:The most significant problem of intra-arterial chemotherapy for advanced paranasal sinus carcinomas and residual cancers supplied by internal carotid artery (ICA) and involving the skull base is the lack of salvage therapies.Objective:The objective of the study was to evaluate the usefulness of intra-arterial chemotherapy including ICA infusion for treating advanced paranasal sinus carcinomas, which have invaded the skull base.Methods:Forty-six patients with advanced paranasal sinus carcinomas supplied by ICA were treated by intra-arterial chemotherapy using CDDP and sodium thiosulphate (STS) as a neutraliser of CDDP toxicity. After evaluating CT angiography, 150 mg m−2 of CDDP was superselectively administered weekly to each feeding artery including ICA four times.Results:The 10-year overall survival rate and progression-free survival rate were 70.7 and 60.2%, respectively. Compared with control group without infusing ICA, recurrences at anterior skullbase or anterior ethomoid sinus were significantly diminished. Of 32 patients in which the orbital apex had been invaded, 29 patients were treated with successful preservation of orbital contents. The CT angiography could efficiently determine all feeding arteries supplying the cancers. Consequently, chemotherapy could be administered on schedule, and side effects were minimal and acceptable.Conclusions:This new method has promising applications in the treatment of advanced paranasal sinus carcinomas involving the skull base.

Deformation of the Outer Hair Cells and the Accumulation of Caveolin-2 in Connexin 26 Deficient Mice

Background Mutations in GJB2, which encodes connexin 26 (Cx26), a cochlear gap junction protein, represent a major cause of pre-lingual, non-syndromic deafness. The degeneration of the organ of Corti observed in Cx26 mutant—associated deafness is thought to be a secondary pathology of hearing loss. Here we focused on abnormal development of the organ of Corti followed by degeneration including outer hair cell (OHC) loss. Methods We investigated the crucial factors involved in late-onset degeneration and loss of OHC by ultrastructural observation, immunohistochemistry and protein analysis in our Cx26-deficient mice (Cx26f/fP0Cre). Results In ultrastructural observations of Cx26f/fP0Cre mice, OHCs changed shape irregularly, and several folds or notches were observed in the plasma membrane. Furthermore, the mutant OHCs had a flat surface compared with the characteristic wavy surface structure of OHCs of normal mice. Protein analysis revealed an increased protein level of caveolin-2 (CAV2) in Cx26f/fP0Cre mouse cochlea. In immunohistochemistry, a remarkable accumulation of CAV2 was observed in Cx26f/fP0Cre mice. In particular, this accumulation of CAV2 was mainly observed around OHCs, and furthermore this accumulation was observed around the shrunken site of OHCs with an abnormal hourglass-like shape. Conclusions The deformation of OHCs and the accumulation of CAV2 in the organ of Corti may play a crucial role in the progression of, or secondary OHC loss in, GJB2-associated deafness. Investigation of these molecular pathways, including those involving CAV2, may contribute to the elucidation of a new pathogenic mechanism of GJB2-associated deafness and identify effective targets for new therapies.

Impact of removing mastoid process for advanced parotid cancer on facial nerve identification, preservation and reconstruction

BackgroundAdvanced parotid cancers more than 4 cm are firmly fixed around the main trunk of the facial nerve that can be hardly detected in narrow working space between mastoid process and parotid cancer. Even though facial nerve was preserved, facial nerve stretching during surgery has significantly serious effect on postoperative facial palsy.ObjectiveTo evaluate usefulness of removing mastoid process in managing advanced parotid cancers to contribute identifying and preserving facial nerve.MethodThe study was performed on 18 advanced parotid cancers which was more than 4 cm and invaded around the facial nerve. Thirteen cases were fresh cases and 5 were recurrent cases.According to a modified Blair incision, the sternocleidomastoid muscle is detached from the mastoid process with electrocautery. When the mastoid process is removed, the main trunk of the facial nerve can be observed from stylomastoid foramen.This procedure was evaluated based on the duration of surgery, working space, and postoperative facial nerve function.ResultsIn eleven cases, facial nerves were sacrificed. Negative margins were achieved in 100% of the patients. The mean duration for removing of the mastoid process to identify facial nerves was 4.6 minutes. The mean size of the removed mastoid process was 2.1 cm in height and 2.3 cm in width, and 1.8 cm in depth. The extended mean working space was 16.0 cm3, and, as a result, the tumors could be resected without retraction.ConclusionRemoving the mastoid process for advanced parotid tumors facilitates identification of the facial nerve and better preservation of the facial nerve function.

Unusual pharyngeal pain caused by acute coronary syndrome: a report of three cases

Most patients complaining of pharyngeal pain have an upper respiratory tract infection or other local explanation for their pain. Here we show 3 rare cases of patients visiting our Otorhinolaryngology Department who had an initial symptom of pharyngeal pain caused by acute coronary syndrome (ACS). An electrocardiogram and a cardiac biomarker test are recommended to exclude ACS with atypical presentation in cases without pharyngolaryngeal findings comparable to pharyngeal pain.

Parapharyngeal Abscesses Caused by Group G Streptococcus

Deep neck abscess is a life-threatening infection that causes laryngeal edema and upper airway occlusion. The predominant bacterial species involved in this disorder is group A streptococcus. Group G streptococcus (GGS) constitutes the normal commensal flora of the human upper airway. Although rarely, it can cause pharyngitis, tonsillitis, and peritonsillar abscess. Here, we report a case of a woman with parapharyngeal abscess caused by GGS. A 56-year-old woman presented to the emergency department with complaints of sore throat and cervical swelling, and a diagnosis of parapharyngeal abscess was established. She had upper airway occlusion, requiring urgent tracheostomy. Endoscopic incision and drainage of the abscess using a specially designed, rigid curved laryngoscope was successfully performed. Since a rigid curved laryngoscope creates a wide viewing field and working space, it was useful for incision and drainage of the parapharyngeal abscess.

Antegrade Bipedicled Submental Island Flap for Anterior Oropharyngeal Defect Reconstruction after Ablative Surgery

Background: The submental island flap (SIF) can be easily and safely harvested in a single stage operation. Although the flap has a good blood supply, for patients who have undergone preoperative radiation or laryngeal suspension, a more reliable flap with a robust blood supply is necessary. Objective: The aim of this study is to evaluate the outcomes of a bipedicled SIF for anterior oropharyngeal defect reconstruction after ablative surgery. Methods: Five patients with anterior oropharyngeal cancer who underwent surgical resection followed by immediate reconstruction with anterograde bipedicled submental island flap from July 2009 to February 2012 were ob-served. Results: Of the 5 patients, aged from 65 to 77 years, in 2 cases there was recurrence after radiation therapy. The mean operation time was 255 mins and blood loss was 149cc (40-350 cc).The patients could consume food orally 11.4 days (mean time)after surgery. The function of swallowing was excellent in all cases and there were no cases of flap complication. Follow up ranged from 15 to 56 months, during which time none of the patients developed recurrence. Conclusion: The antegrade bipedicled SIF for anterior oropharyngeal defect is a valid surgical option because of its high success rate, ease of harvesting and good swallowing function after operation.

Problems Associated with Vacuum-assisted Closure System in Postoperative Head and Neck Fistula

Background: Head and neck fistula is one of the most troublesome complications after head and neck surgery. Fistulas sometimes cause fatal complications such as carotid artery rupture. Vacuum-assisted closure (VAC) system was reported to be useful for managing complex wounds. Methods: A retrospective chart review was performed. Results: We confirmed 7cases with complex fistulas of the head and neck. The VAC system was successful in completely closing the fistula in five of the seven patients. Two patients needed surgical treatment under local anesthesia. In these two cases, the failure resulted from poor collapsibility of the neck tissue caused by prior radiotherapy and deficient sealing of the fistulas around the mandible. The VAC system removes infectious materials and promotes blood flow and healing of complicated wounds. However, when treating complicated wounds the VAC system may be problematic as it can be difficult to obtain an airtight seal because of the intricate contours and stomas of the mandible. Patients with pharyngocutaneous fistulas close to a tracheostoma need a feeding tube to prevent aspiration pneumonia. However, the VAC system enables patients to consume foods without aspiration during the treatment. Conclusions: The VAC system is a feasible treatment option for closing head and neck fistulas when the sealing of the fistula tract is satisfactory. However, it is difficult to close the fistula using the VAC system alone in patients with postradiotherapy, fistulas around the mandible, or infection with drug resistant bacteria.