Nodular fasciitis (NF) is a benign reactive lesion of the soft tissues related to the fascia and characterized by fibroblastic proliferation. The most common site is the upper extremities (46%), followed by the head and neck region (20%). In the orofacial region, the lesion typically develops within the subcutaneous structures overlying the angle and inferior border of the mandible and the zygoma. Magnetic resonance imaging (MRI) findings of NF in the orofacial region are almost unreported in the literature. In the present case report, we describe MRI findings of mental NF in a 19-year-old woman. MRI revealed a well-defined, round soft-tissue mass lying on the mentum. On T1-weighted MRI, the lesion was isointense to skeletal muscle; it was hyperintense to skeletal muscle on T2-weighted MRI, and was enhanced by Gd-diethylenetriamine pentaacetic acid (DTPA). Histologic examination revealed abundant myxoid degeneration dispersed in the lesion. The T2-weighted higher heterogeneous signal intensity was likely due to abundant myxoid degeneration or the cellular component of the lesion. A strong bright signal intensity belt appeared in the periphery of the lesion on Gd-DTPA enhancement. This rim enhancement appeared to represent small arterioles and venules that were visible in the peripheral area on histologic examination.

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Radiation carcinogenesis has been thought as a stochastic phenomenon without any threshold dose of radiation. Although this concept is very important, the presence or absence of a threshold dose in the dose-response relationship is difficult to directly confirm. This review discusses the implication of recent analysis of cancer mortality among atomic bomb survivors and multistep genomic changes involved in human carcinogenesis in relation to the radiation carcinogenesis at low doses. The remarkable similarity in the both shape and magnitude of the dose responses curve is seen between mutational cellular events and cancer incidence among atomic bomb survivors.In view of the increasing evidence for radiobiological mechanisms of radiation carcinogenesis including activation of oncogenes and inactivation of tumor suppressor genes and for analysis in the models of dose-response relationship, it seems likely that radiation is responsible for one mutational event in multistep genomic changes in carcinogenesis.Of the 195 primary cases with squamous cell carcinoma of the tongue treated at National Sapporo Hospital between 1978 and 1990 were reviewed, 152 cases were treated with interstitial needle implant with or without external beam irradiation and 43 cases were treated by operation. The local control rate by needle implant for the primary tongue lesions was 88 % and the cause-specific 5-year survival rate was 82 %. QOL is a serious problem for the cancer patient, but the most important problem is the reasonable quality of treatment provided from the medical therapist. From this point of view, the interstitial implant for early cancer of mobile tongue is the best treatment in preservation of function and form, in the medical cost and treatment period. Form the viewpoint of scientific sociology, we will be discussing the usefulness of radiotherapy and comparison of the structure of radiation oncology in Japan and the United States. Specialists must notify their fellow-physicians in related departments about the advantage of radiation therapy, and the well-balanced cancer therapy is expected to be useful.Crepitus is an important sign for diagnosis of arthrosis of the temporomandibular joint (TMJ). The presence of crepitus can be evaluated by the listening test previously proposed by our group. However, TMJ can be diagnosed by MR imaging showing the disc position and related findings including bony changes and joint effusion. This study investigated the relationship between the presence of crepitus and pathology of the joint. Fourteen joints with crepitus diagnosed by the listening test were examined in this study. TMJ was categorized into four types based on findings on double spin echo MR images. The results were as follows: Of fourteen joints with crepitus, five (36 %) were showed as normal superior disc position. The remaining 9 joints (64 %) were diagnosed with disc displacement, of which, 6 showed reduction, one was without reduction and 2 without reduction were associated with arthrosis. Statistical analysis using t...