Motomasa Sasaki

Two-dimensional jaw tracking and EMG recording system implanted in the freely moving rabbit

A system for simultaneously recording mandibular position in the sagittal plane together with masticatory muscle activity was designed and tested in rabbits. Two small magnetic sensors were implanted in the maxillary bone and a powerful magnet made of a rare earth metal attached to the mandibular central incisors. The magnetic sensors detected the mandibular movements in the sagittal plane by movement of the magnet. Masseter EMG was recorded by fine wire electrodes and amplified by a specially designed amplifier. The necessary preamplifiers were assembled as an integrated circuit (IC) chip in a small housing. The signals from the preamplifier were then passed through a signal processing unit and taped on an instrumentation tape. The system was applied to the freely moving rabbit supplied with food and water during the night. It worked without any trouble for more than 24 h. Since the implanted magnetic sensors were stable for more than 4 months, long-term recording could be done by merely reimplanting the magnet, the cables and the EMG electrodes, which was simple.

Glomus tumor of the cheek: An immunohistochemical demonstration of actin and myosin

A rare case of a buccal glomus tumor was examined by light and electron microscopy. Histologically, the tumor consisted of various vascular spaces surrounded by masses of epithelioid glomus cells, coexisting with a hemangiomatous proliferation of the vessels. Immunohistochemical stainings revealed that the tumor cells were positive for smooth-muscle actin and myosin, with various intensities of the stainings. The electron microscope invariably showed microfilaments in the tumor cells. The results suggest that the glomus tumor cells have characteristics of the smooth-muscle cell and the tumor has a hamartomatous nature.

Dyspnea resulting from accumulation of pleural effusion after radical neck dissection: A case report

The patient became dyspneic 3 days after radical neck dissection on the left side. A chest radiography showed bilateral pleural effusion.During the operation, a lymphatic leak was noted. In this case, the factor of an associated perforation of the pleural had not been demonstrated. Fresh frozen plasma was administered and positive end-expiratory pressure was applied. The patient had no residual pulmonary sequelae.

Autosomal dominant type of endosteal hyperostosis with unusual manifestations of sclerosis of the jaw bones

We report three cases of autosomal dominant type endosteal hyperostosis which occurred in one Japanese family. A new pattern of sclerotic changes in the jaw bones is evident. In all members of the family there was a symmetrical thickening of the diaphyseal cortices of the long bones. The affected bones were only minimally widened and the epiphyses and metaphyses were spared. Endosteal sclerosis of the neurocranium was present with loss of the diploë. The sclerotic changes included enlargement and mottled sclerosis of both the maxilla and mandible, with multiple embedded teeth and odontomas. The ramus of the mandible was spared. Severe sclerosis of the jaw bones was present only in a 28-year-old woman. The 2-year-son showed only focal sclerosis in the mandible, and his grandmother had minimal changes in the skeleton.

An extensive case of cherubism: A long term follow-up case

The present paper describes the radiological features, including CT, of a case of cherubism followed for a relatively long period. The case demonstrated the active phase of the lesion, which progressed from grade 1 to grade 3 during a 6 year period. The radiographic signs, such as increased radiolucency, inflammatory signs and root resorption as well as laboratory data seemed to be important to diagnose the stage of cherubism and to predict the clinical course of the disease.

Cytogenetic studies in patients with cleft lip and/or cleft palate (IV)

SummaryChromosome studies were carried out in 110 patients with cleft lip and/or cleft palate. Major chromosome abnormalities were found in four cases (3.6%). They included two cases of 46, XX, 4p−, one case of 47,XY, +21 and one case of 46,XX, inv(1) (p32q12). The incidence of chromosome abnormalities in patients with cleft lip and/or cleft palate was about 5.2 times higher than that in newborn children.

Unilateral coronoid process atrophy associated with fatty degeneration of the masticatory muscles

Unilateral coronoid process atrophy associated with fatty degeneration of the masticatory muscles in a 76-year-old woman is reported. CT and plain radiogram findings are presented. The patient had no evidence of collagen disease which often causes osteolysis of the coronoid, process and condyle. Although the true cause of this deformity was unclear, a hypothesis of ischemic changes in the nutrient vessels was suggested as an etiologic factor.

Distinctive CT appearance of cervical lymphadenopathy in clinically suspected Cat-scratch disease affecting father and son

This is the presentation of the disitinctive CT manifestation of supracervical and submandibular lymphadenopathy of 2 cases of clinically suspected Cat-scratch disease (CSD) which affected two members of the same family. The characteristic CT appearance of this disease was similar to that of tuberculous adenitis and it must be distinguished from this by its benign self-limiting nature.

Bipedicled cervical skin flap for repair after resection of oral cancer

A technique for immediate reconstruction after resection of intraoral cancer, using a bipedicled cervical skin flap, is reported. This procedure does not necessitate a split-thickness skin graft, and the neck wound may be closed by primary approximation.