Masaru Ogawa

Treatment strategies for large oral venous malformations using intralesional laser photocoagulation

We report two treatment strategies using intralesional laser photocoagulation (ILP) for large venous malformations (VMs) in the oral cavity. ILP is considered to be an effective technique for massive vascular lesion. The satisfactory results could have been obtained, since we started ILP for the treatment of large VMs. Recently, to improve the safety, reliability, and effectiveness of the treatment, we developed modifications of ILP that include a combination of ILP and transmucosal irradiation; and compartmentalization and serial step irradiation. In the former, ILP is performed for a deep layer lesion and transmucosal irradiation with multiple spots fashioned using a single pulse is added for the superficial layer in the same session, to increase the efficacy of regression. In the latter, the lesion is divided by virtual compartment and each area will be sequentially treated by ILP. The irradiated area and total energy in a session should be limited to avoid severe reactions and excessive thermal destruction of surrounding tissue. All treatment outcomes by each technique were satisfactory without serious complications, such as deep ulcer formation, bleeding, or severe swelling developing obstruction. Both treatment strategies improve the safety, reliability, and effectiveness of ILP and make the method less traumatic for patients.

Treatment of microstomia caused by burn with a nasolabial flap--an ingenious approach for tugging and fixation of the oral commissure.

AbstractThe objectives of surgical treatment for microstomia due to cicatricial contracture after burn are to obtain sufficient oral aperture, while maintaining sphincter function of the orbicularis oris muscle, and to secure favorable function for eating and conversation in addition to good oral health.The lips of the mouth have a free border, and the oral aperture, which has been enlarged by the operation, tends to be reduced, because of the actions of the orbicularis oris muscle. When the orbicularis oris muscle is resected, putting a priority on sufficient oral aperture and prevention of redevelopment of contracture, the function of the sphincter is often damaged. With the exception of those cases with deep extensive burn that damages a wide area of orbicularis oris muscle, the muscle should be preserved as expeditiously as is practical. In such cases, however, preventive measures for the redevelopment of microstomia should be established. As a postoperative adjuvant therapy, the usefulness of splint therapy has been suggested in many reports. However, a splint should be used for a long period after the surgery, and in some cases, pain is observed with therapy. When a splint is not used for an appropriate period, microstomia may redevelop. It would be ideal to take preventive measures against the redevelopment of contracture during surgery.We provided treatment with some ingenious attempts for the nasolabial flap to a patient with microstomia caused by cicatricial contracture after burn. We obtained favorable results with no postoperative use of a splint.

Conservative reduction by lever action of chronic bilateral mandibular condyle dislocation

Abstract Aims: The treatment of long-standing dislocation of the temporomandibular joint is broadly classified into open reduction and closed reduction. The current study presents a case of long-standing dislocation of the temporomandibular joint treated 3 years after dislocation. In this study, the authors evaluated the long-term outcome of conservative reduction by lever action of chronic bilateral mandibular condyle dislocation. Methodology: Manual repositioning of temporomandibular joint dislocation lasting for 3 years in a 31-year-old woman was attempted without success; therefore, conservative reduction by lever action was carried out because the patient declined treatment under general anesthesia. Results: The treatment was discontinued after 6 days because of the subluxation of the retaining tooth. The retainer was changed from tooth to screw for intermaxillary fixation, and treatment was reinstituted. Fifteen days later, reduction was achieved and retention was started and continued for 2 months. The outcome was good, with no recurrent dislocation within 24 months of the treatment. Conclusions: Conservative reduction by lever action, involving minimally invasive treatment and little dysfunction, should be considered an optional conservative treatment.

Treatment strategy of a huge ameloblastic carcinoma.

Abstract Ameloblastic carcinoma is a very rare malignant odontogenic tumor. We report a case of secondary-type ameloblastic carcinoma that extended transversally over almost half of the side of the face. Malignant transformation and identification of the malignant region in the large tumor were achieved using L-3-[18F]fluoro-&agr;-methyltyrosine (FAMT)–positron emission tomography (PET); FAMT is transported into cancer cells by L-type amino acid transporter 1 and shows high specificity for malignant tumors. The malignant region determined by microscopic evaluation of resected samples was similar to the region showing high FAMT uptake in PET. Using preoperative FAMT-PET and magnetic resonance imaging, we were able to achieve total resection of the very large tumor, while avoiding excessive resection that could cause severe functional loss or a poor aesthetic facial appearance. We used a modified Weber-Fergusson incision along the nasolabial fold to the labiajugal fold and reconstruction with a pectoralis major muscle flap, and this gave a good aesthetic outcome. Safe surgical resection was possible because preoperative three-dimensional computed tomography angiography was used to identify the position of the main trunk of the external carotid artery, which was closely aligned with the tumor in a posterior direction in the infratemporal fossa region.

Factors influencing internal jugular vein patency after neck dissection in oral cancer

The objective was to investigate factors influencing internal jugular vein stenosis or occlusion after neck dissection, including the reconstructive procedure. The subjects were 73 patients (81 veins) who underwent a modified radical neck dissection, in which the internal jugular vein was preserved, or an extended supraomohyoid neck dissection (E-SOHND). All procedures were performed by the same surgeon. Internal jugular vein patency was evaluated by contrast-enhanced computed tomography. Patency was evaluated in relation to gender, side of dissection, number of pathological lymph node metastases, extracapsular spread of lymph node metastases, radiotherapy, and the reconstruction method (no reconstruction, free flap, or pedicle flap). All internal jugular vein occlusions were on the left side and all except one of these patients underwent radiotherapy. Thus, radiotherapy and left side dissection were significant risk factors for occlusion. Free flap reconstruction was not a risk factor for vein stenosis or occlusion. Patients undergoing reconstruction with pedicled musculocutaneous flaps or E-SOHND were less likely to have vein occlusion. Particular care is required for left neck dissection in patients who have undergone radical neck dissection on the right side. This study suggests that covering the internal jugular vein with the muscle might prevent vein occlusion.

Intraosseous intraneural perineurioma derived from the inferior alveolar nerve with an abnormality of chromosome 22 and expression of the BCR-ABL fusion gene: report of a case and review of recent literature

BackgroundPerineurioma (PN) is a peripheral nerve disease that primarily develops in the limbs and trunk and very rarely occurs in the oral cavity. PN is classified into two types: intraneural perineurioma (INPN) and soft tissue perineurioma (extraneural perineurioma, ENPN). In this article, we report a patient with mandibular body INPN derived from the perineurium of the inferior alveolar nerve.Case presentationThe patient was a 43-year-old male. He consulted our department for a detailed examination of the right mandibular body. A biopsy was performed at another hospital and he was diagnosed with a schwannoma. At his first visit, hypesthesia extending from the right lower lip to the mental region was recognized and enlargement of the right mandibular canal was confirmed with X-ray CT and MRI. Considering the possibility of future tumor growth, we extirpated the tumor under general anesthesia. Cystic tumor was seen continuously in the inferior alveolar nerve. Immunohistologically, the tumor cells were positive for Glut-1, weakly positive for EMA, and weakly positive for Claudin-1, and the histopathological diagnosis was INPN. In addition, absence of the BCR region of chromosome 22 and expression of the BCR-ABL fusion gene were observed by fluorescent in situ hybridization (FISH), and a chromosome 22 abnormality was confirmed. These findings indicated that the disease was a neoplastic lesion.ConclusionExpression of the BCR-ABL fusion gene in INPN that develops in the oral cavity is thought to be very rare, and to the best of our knowledge, ours is the first case to be reported in the literature. About three postoperative years have passed, but findings suggestive of recurrence have not been observed.

Standard morphology of the oral commissure and changes resulting from reconstruction for defects involving the commissure

The aim of this study was to characterize the standard morphology of the oral commissure and to describe the changes after reconstruction in patients with through-and-through cheek defects involving the oral commissure. Indices for the morphological analyses of the commissure were derived from examinations of 50 normal Japanese volunteers. Ten patients with full-thickness cheek defects involving the commissure were then evaluated. All of these patients underwent free flap reconstruction with vermilion advancement flaps from the remaining vermilion. The morphology of the commissure with the mouth closed was classified based on the point of entrance of the vermilion into the oral cavity. In normal volunteers, the commissure pattern consisting of the entrance of the upper vermilion into the oral cavity before the lower vermilion and just prior to forming the oral commissure was considered to be the standard. However, in the reconstructed cases, there was an increase in the pattern in which the lower vermilion enters the oral cavity before the upper vermilion for the remaining commissure postoperatively, especially when the lower lip defects were greater than those of the upper lip. It is important to refer not only to the standard morphology of the commissure, but also to the changes according to the extent of resection and the method of reconstruction.

Granular cell tumors of the tongue: fibroma or schwannoma

BackgroundGranular cell tumors are benign lesions that typically occur in the oral cavity, but can also be found in other sites. However, the characteristics of these tumors are unclear. Thus, the present study aimed to investigate the immunohistological characteristics of these tumors of the tongue.MethodsSeven patients were treated for granular cell tumors of the tongue at our institution during 2003–2017. Paraffin-embedded specimens were available for all cases; thus, retrospective immunohistochemical analyses were performed.ResultsAll cases exhibited cytoplasmic acidophilic granules in the muscle layer of the tumor. Both the normal nerve cells and tumor cells also stained positive for PGP9.5, NSE, calretinin, and GFAP. A nucleus of tumor cells was typically present in the margin. The PAS-positive granules were also positive for CD68 (a lysozyme glycoprotein marker). Various sizes of nerve fibers were observed in each tumor, and granular cells were observed in the nerve fibers of a representative case.ConclusionsBased on our immunohistological findings, granular cell tumors may be derived from Schwann cells, and the presence of CD68 indicates that Wallerian degeneration after nerve injury may be a contributor to tumor formation. Thus, a safe surgical margin is needed to detect the infiltrative growth of granular cell tumors.