Mandibular Swing Research Articles

Reconstruction of Transoral Robotic Surgery Defects: Principles and Techniques

Early functional and oncological outcome studies suggest that transoral robotic surgery (TORS) may have a role for early stage cancers of the oropharynx. Unlike with traditional mandibular swing or pharyngotomy approaches, access to the oropharynx for reconstruction in TORS cases is limited. Maintaining a good functional result necessitates preserving physiological function where possible. The principles that should guide reconstructive surgeons include maintaining a velopharyngeal sphincter to prevent velopharyngeal insufficiency, maintaining sensate mucosa and restoring bulk in the tongue base to prevent aspiration, maintaining separation between the cervical and pharyngeal components, and covering exposed vessels in the pharynx. We present here principles and surgical techniques of TORS to reconstruct oropharyngeal defects using a subsite-based approach using secondary healing, local musculomucosal flaps, and free tissue transfer guided by the above principles.

Removal of Angiofibroma with Maxillary and Mandibular Swing: A Clinical Report

ABSTRACTJuvenile nasopharyngeal angiofibroma is vascular tumor found in adolescent males. With development of endoscopic fraternity, tumor can be addressed successfully with endoscopic approach; but one needs maximum exposure for large angiofibroma with local infiltration around. Maxillary and mandibular swing technique for removal of the tumor gives excellent exposure and good control on vascularity of the tumor.Postoperative follow-up for 1 year has shown minimal visible scar, cosmetic deformity in the patient.How to cite this articleGhorpade CV, Deo RP, Thorat RD, Devane SD. Removal of Angiofibroma with Maxillary and Mandibular Swing: A Clinical Report. Int J Otorhinolaryngol Clin 2012;4(3):151-155.

当科における副咽頭間隙腫瘍手術症例の検討

This study is a retrospective review of the clinical records of patients operated on for parapharyngeal space (PPS) tumors. Between April 2005 to September 2011, 8 patients (2 men, 6 women, mean age 61.3 years) with primary PPS tumors underwent surgical resections by the same operating team. Different surgical approaches were used according to the type of lesion, exact location, and size: transcervical in 3 patients, transcervical-transparotid in 4 patients, and transparotid in 1 patient. Mandibulotomy was performed in 3 patients (mandibular swing in 1, subcutaneous mandibular splitting in 2). The PPS tumors were all successfully removed with no significant perioperative complications. One patient presented with Frey syndrome 1 year later. Histological examination of the resected tumors showed 6 salivary gland tumors and 2 schwannomas. Of the 6 salivary gland tumors, 2 were malignant. Our experience in the treatment of PPS tumors confirms the importance of preoperative assessment before every surgical resection in order to plan surgical treatment with a safe approach and which reduces aesthetic/functional damage. Intraoperative monitoring of multiple cranial nerves using NIM nerve monitoring systems is useful in the identification and preservation of neurological function in schwannoma.

Myoepithelial Cell-Rich Pleormorphic Adenoma of Minor Salivary Gland of Parapharyngeal Space

Parapharyngeal space tumors are rare and constitute only 0.5–1.0% of head and neck tumors. Minor salivary gland tumor is still rare in parapharyngeal space. We are reporting a case of pleomorphic adenoma of minor salivary gland of parapharyngeal space. A 42-year-old female presented with a history of mass in the oropharynx for 3 years. She presented with “hot potato voice” and dysphagia. CECT and MRI were done, showing large parapharyngeal space tumor. FNAC was suspicious for tumor of nerve cell origin. Tumor was excised using “paramedian mandibulotomy with mandibular swing approach”. Histopathological examination was inconclusive, suggesting possibility of extraskeletal myxoid chondrosarcoma, solitary fibrous tumor, neurogenic tumor. On immunohistochemistry, tumor was positive for cytokeratin, EMA (dim), S-100, and P 63 and negative for SMA thus proving the case as myoepithelial cell-rich pleomorphic adenoma.

Mandible preserving pull-through oropharyngectomy for advanced oropharyngeal cancer: A pilot study

Objective Through our experiences in the parapharyngeal space (PPS) surgery, we have learned that it is possible to gain wide exposure of the PPS near to the skull base with a transcervical approach alone. Thus, we presumed that if this type of transcervical approach would be combined with a transoral approach, a less invasive oropharyngectomy without mandibulotomy and lip-splitting might be feasible for the resection of advanced oropharyngeal cancer, sparing the morbidities associated with conventional mandibular swing approach or its modified procedures. We termed this method as a mandible preserving pull-through oropharyngectomy (MPPO) and evaluated its feasibility and efficacy in this pilot study. Materials and methods MPPO was applied for a series of 7 patients with advanced lateral and/or upper oropharyngeal cancer including 2 patients with T4 stage. Our current application of MPPO excludes tumors, which involves mandibular bone, the higher part of the medial pterygoid muscle, and the lateral pterygoid muscle. Results Safe and sufficient excision of tumors was feasible by MPPO avoiding morbidities associated with mandibulotomy or lip-splitting without compromising oncological outcomes. Conclusions Although preliminary, our favorable outcomes indicate that MPPO might be a useful alternative to conventional mandibular swing approach or its modified procedures for selected cases with advanced oropharyngeal cancer. Further accumulation of data is encouraged.

Principles and Practice of Oral Cancer Surgery

The management of malignant tumors of the oral cavity requires that the resection should be performed with adequate negative margins. To this end, the surgeon is sometimes required to increase the access to the oral cavity to resect with clear margins although most of our resections can be carried via the transoral route. This article highlights some of the most common surgical accesses to the oral cavity: Peroral approach, mandibulotomy and mandibular swing approach, visor flap approach, upper & lower cheek flap approach, pull-through technique. Also, various modes of management are grossly described according to primary site, size, and stage of the tumors.

翼口蓋窩・側頭下窩腫瘍に対するアプローチ法の検討

Approaches to pterygopalatine and infratemporal fossa lesions are numerous because they are relatively surgically inaccessible. We report 9 cases of pterygopalatine and infratemporal fossa lesions. We treated 2 subjects with benign schwannoma using transmaxillar sinus and orbitozygomatic approaches. We used resection without facial skin incision, assuming that presurgical intraarterial embolization and navigational use was important in removing tumors safety with minimal invasion. One case involved lower infratemporal fossa adenoma. We used a mandibular swing for en block removal. We treated 3 with recurrent palatal carcinoma using maxillary swing. In 2 with lesions extending laterally to the parapharyngeal space, mandibular swing was added to maxillary swing. We treated 1 with recurrent chordoma in the infratemporal fossa using maxillary swing to preserve postoperative function and facial form. We treated 2 with massive infratemporal fossa tumors using an infratemporal approach. One of these 2 had a massive tumor invading the maxilla, necessitating maxillectomy with a Weber incision. We concluded that surgical approaches with wide access to safety must be used to resect tumors completely in those with malignancies

Clinical study of parapharyngeal space tumours

This study reviewed 24 cases of parapharyngeal space tumour treated at Kurume University Hospital between 1990 and 2007. Histological diagnoses were generally obtained from the excised tumour (22/24). Seventy-seven per cent of the parapharyngeal space tumours were benign and 23 per cent were malignant. Thirty-eight per cent (eight of 22) of these tumours were pleomorphic adenomas and 23 per cent (five of 22) were schwannomas. A transparotidectomy and transcervical approach were used in 88 per cent (15/17) of benign tumours. A mandibular swing approach was used for one malignant tumour. Post-operative complications were identified in 16 of 22 patients. The most common complication, facial nerve paralysis, was identified in eight patients, and seven of these patients demonstrated first bite syndrome. In consideration of the high incidence of post-operative complications, the surgical approach should therefore be carefully selected when treating patients with parapharyngeal space tumours.

Partial maxillary swing approach for removal of the tumors in the retromaxillary area

Objective Removal of tumors around the pterygoid process poses difficult challenges. Our method for removal of tumors in this area using a modification of the maxillary swing approach is reported. Methods A retrospective study of five cases was performed using the partial maxillary swing approach. Like the “maxillary swing approach”, the maxilla is swung laterally with the facial skin; however, only two-thirds of the anterior maxillary bone is swung. Results All tumors were safely removed using the partial maxillary swing approach alone, with the exception of one patient who needed an additional mandibular swing. No facial palsy, masticatory problems or necrosis of the maxilla were observed in any cases. Conclusions The partial maxillary swing approach offers a wide surgical field of the lesion around the posterior part of the maxilla and pterygoid process without severe complications and is useful for removal of tumors in these areas.

Surgical Strategy for Tumors Located in or Extending From the Intracranial Space to the Infratemporal Fossa -Advantages of the Transcranial Approach (Zygomatic Infratemporal Fossa Approach) and the Indications for a Combined Transcranial and Transcervical Approach-

The surgical strategy for tumors located in or extending from the intracranial space to the infratemporal fossa was analyzed in 12 cases with various pathologies. A case of mandibular nerve schwannoma, which extended 1 cm below the external orifice of the foramen ovale, was completely removed via the epidural subtemporal approach without zygomatic osteotomy with partial removal of the middle cranial base. The inferior margin of infratemporal tumor could be accessed via the transcranial route with zygomatic or orbitozygomatic osteotomy without complications including facial nerve injury in nine cases, and the lowest level of the infratemporal tumors was approximately 4.5 cm below the outer surface of the middle cranial base. In five of these 9 cases (2 schwannomas, 1 myxoma, 1 chondrosarcoma, and 1 malignant peripheral nerve sheath tumor), the tumors were localized in the infratemporal fossa, and in the other 4 cases (2 meningiomas, 1 glioblastoma, and 1 ameloblastoma), the tumors extended to both the intracranial space and the infratemporal fossa. In two cases (recurrent jugular schwannoma and mandibular osteosarcoma), a combined transcranial and transcervical approach (mandibular swing approach) was essential, because the resection line of the lower margin was too far from the middle cranial base. These results indicate that the transcranial approach, with or without zygomatic or orbitozygomatic osteotomy (zygomatic infratemporal fossa approach), is safe and effective for removal of some infratemporal tumors, and that a combined transcranial and transcervical approach is useful for removing infratemporal tumors with extensive downward extension.

Surgical Experience with Skull Base Chordomas/Chondrosarcomas

Aims: A retrospective analysis of the surgical results of 43 cases of chordomas and chondrosarcomas operated from January 1980 to August 2007 is presented. Material and Methods: While most cases (34) involved upper and mid clivus (sphenoid and ethmoid extension in 10, middle fossa/posterior fossa straddling petrous apex in 8, middle fossa with infratemporal extension in 3), the remainder (9) involved the lower clivus. Fifty-two surgical procedures were done in 43 patients. Various procedures included extended frontobasal (12 cases), subtemporal zygomatic (9), frontotemporal with orbitozygomatic transsylvian (7), petrosal approach (4), transsphenoidal (2), subtemporal (4), extreme lateral/transcondylar (5), transoral-transaltopharyngeal (2), mandibular swing retromaxillary (2), extended middle fossa (2), and posterior petrosectomy (3). Results: We could achieve radical excision (total/near total) in 20 cases (47%), subtotal in 17 (39%), partial in 5 (12%), and biopsy in 1. Thirteen patients underwent adjuvant radiotherapy. There was one operative mortality. During the mean follow-up period of 60 months, 21 cases were independent with cranial nerve deficits, 15 underwent surgery for tumor recurrence, and 6 patients expired. Conclusion: Due to the lesions' multicompartmental locations and invasiveness, the preoperative analysis of the anatomical extent of the lesion is the most important factor in planning a surgical approach.

副咽頭間隙腫瘍の臨床的検討

We reviewed 23 cases of parapharyngeal space tumors that were treated at Kurume University Hospital between 1990 and 2006. Histological diagnoses were obtained by excision of tumors (21/23). Seventy-six percent of the parapharyngeal space tumors were benign, and 24% were malignant. Thirty-eight percent (8/21) of these tumors were pleomorphic adenoma, and 24% (5/21) were schwannoma. The trans-parotid approach and the trans-mandible approach were used in 88% (14/16) of benign tumors, the mandibular swing approach was used in one case of malignant tumor. Postoperative complications were identified in 16 of the 21 patients. The most common complication, facial nerve paralysis, was identified in 8 patients and 7 patients were demonstrated first bite syndrome. In consideration of the high incidence of postoperative complication, the surgical approach should be carefully selected when treating parapharyngeal space tumors.

Comparison of straight and step mandibulotomy in mandibular swing procedures

Objective: The study was conducted to compare straight and step osteotomies during mandibulotomy. Methods: This study was conducted on 14 patients (7 step osteotomies, 7 straight osteotomies) who underwent surgical resection of the oropharyngeal tumour; access to the tumour site was gained through the straight or step mandibular swing procedures. The study records like clinical photographs, orthopantamogram which were made at the preoperative period, 10 days postoperative and 1 year postoperatively for the study purpose. Results: The results indicate complications in both procedures, two cases of osteoradionecrosis and two cases of infection of the osteotomy site which required plate removal, one temporomandibular pain. Although patients should be advised of the potential for the functional problems with these procedures, they can be assured that these are likely to be relatively minor in significance. Conclusion: This study concluded that mandibulotomy has a place in the management of malignancies and both straight and step mandibular osteotomies provide adequate access to the tumour site and clinical and radiographic examination showed no difference in easy/difficult in splitting the mandible, reapproximation of the osteotomy sites and postoperative healing of the osteotomy sites.

Facial Swing for Central and Lateral Skull Base Exposure

Mandibular and maxillary swings, together with facial bipartition, provide the skull base surgeon with a very convenient exposure of the central and lateral skull base. The mandibular swing opens up the lateral skull base and provides excellent exposure for resection of lesions such as neurofibroma and glomus tumors. The maxillary swing provides access to central skull base tumors. These may be benign (for example, vascular) or malignant. The surgical technique, the anatomy of the area, and how to prevent complications will be presented with dissection specimens and case presentations.

P.216 Angiosarcoma of the lower lip in a young adult. A case report

Through our experiences in the parapharyngeal space (PPS) surgery, we have learned that it is possible to gain wide exposure of the PPS near to the skull base with a transcervical approach alone. Thus, we presumed that if this type of transcervical approach would be combined with a transoral approach, a less invasive oropharyngectomy without mandibulotomy and lip-splitting might be feasible for the resection of advanced oropharyngeal cancer, sparing the morbidities associated with conventional mandibular swing approach or its modified procedures. We termed this method as a mandible preserving pull-through oropharyngectomy (MPPO) and evaluated its feasibility and efficacy in this pilot study.MPPO was applied for a series of 7 patients with advanced lateral and/or upper oropharyngeal cancer including 2 patients with T4 stage. Our current application of MPPO excludes tumors, which involves mandibular bone, the higher part of the medial pterygoid muscle, and the lateral pterygoid muscle.Safe and sufficient excision of tumors was feasible by MPPO avoiding morbidities associated with mandibulotomy or lip-splitting without compromising oncological outcomes.Although preliminary, our favorable outcomes indicate that MPPO might be a useful alternative to conventional mandibular swing approach or its modified procedures for selected cases with advanced oropharyngeal cancer. Further accumulation of data is encouraged.

副咽頭間隙に生じたダンベル型神経鞘腫の１例

A case of schwannoma extending from the parotid gland to the parapharyngeal space is presented. The patient was a 53-year-old woman. She was referred to us because of a swelling under the left auricle. CT scanning and MRI revealed a tumor extending from the deep lobe of the parotid gland into the parapharyngeal space, compressing the stylomandibular tunnel. This tumor was referred to as a “dumbbell tumor” because of its special shape. Such tumors are rare. The tumor was removed by an extraoral and mandibular swing approach. The histopathological diagnosis was schwannoma with a mixture of Antoni type A and B components. After sugery, no evidence of recurrence has been observed to date.

Primary parapharyngeal space tumors in a Mexican cancer center

To describe clinical and demographic characteristics of the parapharyngeal space tumors and assess surgical approaches used to treat them at our institution. A retrospective and descriptive study of the parapharyngeal space tumors, excluding paragangliomas, treated from June 1991 to October 2002 in a cancer center. The study population included 21 patients, 8 men and 13 women, average age of 41 years (range, 20 to 70 years). Fine needle biopsy was done in 5 (24%) patients. Computed tomography (CT) was performed in all patients, and only a few required magnetic resonance image (MRI). Surgical approaches included transcervical alone or in combination with parotidectomy, transoral, or transmandibular (mandibular swing) approach. Laminectomy and segmentary approaches were also performed in 1 patient each. Sixteen (76%) patients had benign lesions and 5 (24%) had malignant tumors. Neurogenic tumors represented 57% of all tumors. Mean tumor size was of 6.7 cm (range, 3 to 11 cm). Six (29%) patients received adjuvant radiotherapy. Complications occurred in 6 (29%) patients, 4 (19%) of which were nervous injuries associated with peripheral nerve sheath tumors. Median disease-free follow-up survival was 33 months (range, 2 to 184 months) despite being an heterogeneous group of histologies. Parapharyngeal space is a rare location for head and neck tumors. Cervical approach should be the first choice for large tumors; transoral approach is reserved for tumors less than 3 cm. Conversion to mandibular swing approach when the cervical approach is not offering proper exposure for tumor resection is indicated. Preoperative histologic diagnosis is not required. Nevertheless, CT scan should always be performed in order to exclude paragangliomas, distinguish prestyloid from poststyloid lesions, and to assess the extension of the tumor as well as its relationship with adjacent structures.

翼突下顎隙に認められた多形性腺腫の１例

A 40-year-old-woman presented with swelling and pain of the right buccal mucosa. The swelling protruded intraorally. An incisional biopsy revealed pleomorphic adenoma in the pterygomandibular space. The tumor was surgically removed via a mandibular swing approach. The entire resected specimen was submitted to histopathological evaluation, which showed solid and myxomatous areas, typical of pleomorphic adenoma, throughout the tumor specimen. No recurrence was observed during 3 years of follow up.

Vagal Paraganglioma Arising in the Parapharyngeal Space : A Case Report

A rare case of paraganglioma arising in the vagus is reported. A 36-year-old woman complained of neck swelling. She underwent CT, MRI and angiography and was diagnosed as hypervascular tumor occupying the right parapharyngeal space. This tumor was totally removed using a mandibular swing approach. Prior to tumor removal, feeding artery was ligated, and relatively little bleeding (244 ml) was noted for such a case. After the surgery, she developed difficulty in swallowing, hoarseness and Homer's syndrome. She underwent additional surgeries: cricopharyngeal myotomy, laryngeal elevation and arytenoid roatation. Except these problems, the postoperative course was uneventful and she was free from disease for 12 months.

Infratemporal Fossa Dissection for Cancer Extending to Masticator Space

The local control of oral, oropharyngeal, and maxillary cancers extending to the masticator space is poor because the surgical approach to the deep margin is difficult. We present an inf ratemporal f ossa approach for en bloc surgical resection of the masticator space. Seven cases involving the masticator space were surgically treated. Five cases were resected with inf ratemporal f ossa dissection (dissected group). Two cases were resected with the mandibular swing approach (non-dissected group). The local control rate of the dissected group was 80% and that of the undissected group was 0 %. The dissected group had functional problems of malocclusion and chewing, however they kept fair to good oral intake. To obtain better local control of deeply invaded cancers, en bloc dissection of the involved space is important.