Biomedical subjects

Masahiro Kawana

Publications and source records attributed to Masahiro Kawana.

4 recordsLinked to original sources

PubMed2003

Treatment of ranula--excision of the sublingual gland versus marsupialization.

The purpose of this work is to estimate optimum surgical treatment of ranula according to the type of the lesion. Nine patients with ranula surgically treated between 1989 and 2000 were investigated retrospectively. Six patients had sublingual type ranula and three had submandibular type. In five cases including recurrence cases, the sublingual gland was excised. Marsupialization was performed for four cases, which were superficial, protruded and within 2 cm of diameter. In all cases, histopathological diagnoses were pseudocysts without epithelial lining and there was no recurrence. Almost all ranulas are pseudocysts from the sublingual gland, therefore excision of the sublingual gland is considered to be a reasonable and radical treatment. For the small sublingual type, which is superficial, protruding and smaller than 2 cm in diameter, marsupialization is also a useful modification of surgical treatment of ranula.

Adolescent↗

PubMed2003

[Head and neck malignant tumors in Niigata Prefecture. The first report: demographics in 4,053 cases].

In 1986, the Niigata Registration Committee of Head and Neck Malignant Tumors was established by otolaryngologists in Niigata Prefecture to register cases of head and neck malignancies. Between 1986 and 1999, 4,053 cases were registered and we epidemiologically analyzed them. Men accounted for 2,866 (70.7%) and women for 1,187 (29.3%). The mean age and standard deviation of the age at diagnosis were 63.4 and 12.4 in men and 59.5 and 16.0 in women. The larynx was the most common site (1,154 cases) in men, followed by the oral cavity (360 cases), hypopharynx (273 cases), mesopharynx (239 cases), and maxillary sinus (154 cases). The thyroid gland was the most common site (416 cases) in women, followed by the oral cavity (214 cases), nasal cavity and paranasal sinuses (excluding the maxillary sinus) (76 cases), salivary glands (72 cases), and mesopharynx (71 cases). The site with the highest mean age was the lip (71.3 years old) in men and the larynx (68.7 years old) in women. The thyroid gland showed the lowest mean age for both genders (men: 56.7, women: 53.6), and that markedly lowered the female mean age because the thyroid gland accounted for one third of all cases in women. Comparing our data to national statistics, the incidence of oral malignancy was almost half in our data. We concluded that, in Niigata Prefecture, the dental professions treated as many cases of oral malignancy as we did. A high gender ratio (male/female) was seen for the larynx (22.2), hypopharynx (4.3), and mesopharynx (3.4). It was more than 1 and less than 2 for the oral cavity, salivary gland, neck lymphoma, ear, and nasal cavity and paranasal sinuses (excluding the maxillary sinus). The thyroid gland showed the lowest gender ratio (0.3), which was the only female-dominant site. We concluded that many sites of malignant head and neck tumors have a lower gender ratio than previously anticipated.

Adolescent↗

PubMed2002

Malignant lymphoma in the head and neck associated with benign lymphoepithelial lesion of the parotid gland.

Lymphoepithelial lesion is a benign lymphoproliferative disease occasionally arises in the salivary glands, but association with malignant diseases or autoimmune diseases has also been discussed. We herein present three cases of malignant lymphoma arose in the parotid gland and the lacrimal gland, following parotid surgery for benign lymphoepithelial lesion (BLEL) of the parotid gland. Two cases had mucosa associated lymphoid tissue (MALT) lymphoma in the parotid gland; one arose in the ipsilateral parotid gland as a recurrent swelling, and the other arose in the contralateral parotid gland of the previous BLEL surgery. The third case of malignant lymphoma arose in the lacrimal gland on the ipsilateral side, and the following contralateral parotid gland remained BLEL. All three patients were female, and one patient had a past history of Sjögren's syndrome and Hashimoto's disease. All three patients were treated by chemotherapy and one patient received additional radiotherapy. To follow-up lymphoproliferative diseases in the salivary glands such as BLEL, careful observation should be made on the same gland, other major salivary glands, and other organs in the head and neck, especially in females with autoimmune diseases.

Aged↗

PubMedDate not supplied

MR findings with dynamic evaluation in Riedel's thyroiditis.

We reported the findings on MRI in a patient with proven Riedel's thyroiditis. The lesion was seen as slightly heterogeneous hypointensity on both T1- and T2-weighted images and had a mild enhancement after administration of gadpentate dimeglumine (Gd-DTPA). Dynamic MR study showed gradual increase in signal intensity of the lesion. These findings were different from those of thyroid neoplasms and were considered to reflect the mixture of inflammatory cells infiltration and fibrosis of Riedel's thyroiditis.

Contrast Media↗