Yuka Uchiyama

Postoperative maxillary cysts: Magnetic resonance imaging compared with computerized tomography

OBJECTIVES The aim was to investigate magnetic resonance (MR) and computerized tomography (CT) images and compare MR and CT image features of postoperative maxillary cysts (POMC). STUDY DESIGN We retrospectively evaluated MR and CT images of 7 POMC patients. Number of the cysts, border, bone expansion, CT value, signal intensity, and contrast enhancement were observed. RESULTS On CT images, 15 cysts were detected. Fourteen cysts showed smooth border. Bone expansion was found in 10 cysts. Mean CT value of each cyst ranged from 23 to 50 Hounsfield units. On MR images, 18 cysts were detected. Twelve cysts showed smooth border. Bone expansion was not observed. Most cysts showed intermediate signal intensity on T1-weighted images, and high or nonhomogeneous intermediate/high signal intensity on T2-weighted images with the fat suppression technique. No cyst showed contrast enhancement in both examinations. CONCLUSION The CT images revealed bony information, and the MR images clearly demonstrated border of POMC. POMC should be evaluated with both CT and MR imaging.

Effectiveness of Cepharanthin in decreasing interruptions during radiation therapy for oral cancer

ObjectivesTo examine the effectiveness of Cepharanthin (Kakensyoyaku, Tokyo, Japan) at decreasing side effects during radiation therapy for oral cancer and thereby allowing the completion of radiation therapy without interruption.MethodsTwo hundred fifteen patients diagnosed with oral cancers were assigned to either Cepharanthin or control groups and underwent external beam irradiation. The completion of the course of radiation therapy and the occurrence of side effects such as mucositis, dysgeusia, and xerostomia during the radiation therapy were evaluated and compared.ResultsThe completion rate was 87.4% for the Cepharanthin group versus 67.0% for the control group, and the difference was statistically significant (P < 0.01). Mucositis did not appear in 58 of 127 cases (45.7%) in the Cepharanthin group or in 21 of 88 cases (23.9%) in the control group. Mucositis developed in 24.6% of the Cepharanthin group and 53.7% of the control group within 2 weeks of irradiation. There were significant relationships between the use of Cepharanthin and the development and timing of mucositis (both P < 0.01).ConclusionsCepharanthin improved the completion of radiation therapy without interruption and reduced or delayed the development of mucositis during radiation therapy for oral cancer.

A case report of primary gingival angiosarcoma.

Angiosarcoma is a rare malignant neoplasm and primary angiosarcoma is extremely rare. This study reports clinico-pathological features and CT image finding of a case of primary angiosarcoma in the upper gingival and a review of previously reported cases of primary gingival angiosarcomas including the present case.

Ameloblastic fibro-odontoma arising in the mandible: three case reports

Ameloblastic fibro-odontoma is a rare mixed odontogenic tumor. Here, we describe three cases of ameloblastic fibro-odontoma. We present both conventional radiography and computed tomography (CT) images from two cases and conventional radiography from one case. Given the CT values of the tumor’s radiopaque components, CT was very useful for the diagnosis of ameloblastic fibro-odontoma.

Influence of mouthguard on temporomandibular joint

The aim of this study is to examine whether wearing a mouthguard (MG) has an influence on temporomandibular joint (TMJ) components (i.e., the condyle and the articular disk) and whether clenching with a resilient MG has an effect on the same components. Twenty‐six healthy volunteers (15 females, 11 males) with an age range of 26–42 years old (median 28 years) participated in this study. Among all 52 joints in the 26 subjects, anterior disk displacement (AntDD) was recognized in 15. Thus, we classified the 52 joints into two groups, the AntDD group and the Normal group. Resilient thermoplastic materials were used to fabricate two types of MG, one that raised the vertical dimension height by 3 mm and another that raised it by 6 mm. Subjects were scanned with/without two types of MG with/without clenching by magnetic resonance imaging (MRI). The movement of the condylar head and articular disk was measured in the magnetic resonance images using the special subtraction technique. Wearing the MG without clenching did not have a negative influence on the TMJ and clenching in the Normal group. In the AntDD group, however, the relationship between the disk and condyle was affected by clenching and the degree of disk displacement was worsened by clenching with the thicker MG. From our results, we recommend that athletes with an internal derangement of the TMJ not wear the thicker MG and attention should be paid to its setting. And the subtraction technique using MRI was thought as a good tool for detecting a slight change in the TMJ.

Osteosarcoma in the maxilla : a case report

We encountered a case of osteosarcoma in the maxilla of a 20-year-old man, who complained of gingival swelling of the left maxillary molar. Limited bone destruction was detected on conventional radiography, including panoramic radiography, whereas a more extensive lesion was seen on computed tomography (CT), and new bone formation was clearly seen in the three-dimensional CT image. CT was superior to conventional radiography, including panoramic radiography, for detecting the extent of bone destruction and new bone formation in the lesion, allowing more accurate evaluation of the osteosarcoma.

Diagnostic imaging findings for mandibular metastasis from gastric adenocarcinoma.

A case of metastatic adenocarcinoma from gastric cancer to the mandibular canine region is reported. Computerized tomography (CT) scanning revealed a small round enhanced inhomogeneous mass, indicating an osteolytic lesion on radiographic classification. Although chemotherapy and radiation therapy was performed, the mass increased, and a subsequent CT scan showed further calcifications within the tumor, indicating progression from an osteolytic to a mixed lesion.

First brachial cleft cyst in the parotid area

A first brachial cleft cyst was detected in the parotid area of a 66-year-old Japanese man complaining of swelling in the left upper neck. Although the lesion was suggestive of a cyst, based on computed tomography and magnetic resonance imaging, the lesion was misdiagnosed as a benign tumor, because it was thought to localize to the parotid and most lesions occurring in the parotid gland are tumors. The histopathological diagnosis was a first brachial cleft cyst or a so-called lymphoepithelial cyst. This case demonstrates that it may be difficult to differentiate a cyst from a benign tumor in the parotid area.

Longitudinal study of patients with TMJ dysfunction by tomographic examination: Condylar position and clinical sign

For patients with TMJ dysfunction, operators often change the condylar position by various methods. The aim of this study is to investigate how much the changes with time of condylar positions are related to the changes of clinical signs.The subjects were 584 joints of 127 patients with TMJ dysfunction to whom the serial lateral TMJ tomography was performed more than twice.In the most of cases where the condylar position had moved downward, inter-incisal distance had increased and TMJ noise had ameliorated. Furthermore, in many cases where the condylar position had moved forward, the amelioration of the TMJ pain was observed.It was considered that those ameliorations occurred because the positional relationship between the condylar head and the articular disk or posterior attachment had been improved.

Neurofibromatosis Type 1 in the Mandible

Neurofibromatosis type 1 (NF1) was first described in 1882 as a hamartomatous disorder of neural crest derivation. We present the imaging of a 65-year-old woman with NF1. Computed tomography revealed that there were three major findings presented: skeletal deformity, an area of fat (probably related to mesodermal dysplasia), and benign neoplasm within the masticator space. Moreover, masticatory muscles were hypoplastic.