Biomedical subjects

T Iinuma

Publications and source records attributed to T Iinuma.

At least 55 records · Page 3Linked to original sources

PubMed1991

[A case report of lymphoepithelial cyst in the parotid gland].

A 57 year-old Japanese male was seen with the chief complaints of left parotid gland swelling, pain, trismus. At the initial visit, a subcutaneous mass, measuring 50 x 70mm, was seen in the left parotid region. The mass was moderately tender and the consistency was soft anteriorly and elastic firm posteriorly. The mobility was restricted with no change in the skin covering the mass. The saliva from the left parotid gland was normal in colour and contents. Various imaging modalities were done preoperatively including CT, MRI, ultrasonography and aspiration biopsy under the ultrasonographic guide. None was thus conclusive for the differential diagnosis and our tentative diagnosis was a cystic lesion in the parotid gland. A partial parotidectomy was performed under general anesthesia and the cystic lesion, measuring 20mm in diameter, was found in the deep lobe. The cyst showed no connection to the external ear canal, and tracts and fistulae were absent. Histopathological report lead to the definite diagnosis of lymphoepithelial cyst. A mild and incomplete facial palsy on the left had been noted for more than 10 years and this, however, improved after the surgery.

Humans↗

PubMed1991

[Isolated medial orbital wall fracture and late fronto-ethmoidal mucocele].

Twenty-one cases of isolated medial orbital wall fractures were reported and CT findings by coronal planes were evaluated as to the effects of fractures upon the ethmoidal cells and nasal meati. Three coronal planes, which respectively contain such structures as Agger nasi, Pars membranacea and superior meatus, were selected for the study. The extent of fracture was evaluated by dividing the medial wall into three equal portions, i.e., superior, middle and inferior. The prolapsed volume was evaluated in three classes of occupying 1/3, 2/3 and 3/3 of the ethmoid. The presence of soft tissue density was recorded at the three surfaces, upper, medial and lower, around the prolapsed orbital content. The extent of the fracture was most often seen in such cases as involving all the three divisions in 41.3%. The prolapsed volume occupying 1/3 was seen in 28, 6%, and 2/3 in 23.8%. The presence of soft tissue density was seen in 38.1% of upper surface, in 36.5% of medial, and 11.1% of lower. Summarizing the total effects of the fractures, the coronal plane containing Pars membranacea was most severely damaged followed by the plane of the superior meatus. Two rare cases of fronto-ethmoidal mucoceles, caused by the traumas of 23 and 14 years before respectively, were also included and reported. The ophthalmological prognosis was favorable in 90.5% of cases by observations extending more than 6 months. Five cases were surgically treated including two cases of mucoceles.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[The vasoactivity of endothelin in the nasal mucosa].

Endothelin (ET), a novel endothelium-derived vasoconstrictor peptide with 21 amino acid residues, has recently been isolated from the supernatant of cultured porcine aortic endothelial cells. Several authors reported preliminary results demonstrating that ET has a potent contractile action in vascular smooth muscles, but its effect is slightly different in each target tissue. In the present study, we have examined the vasoactivity of ET in human and canine nasal mucosa with in vitro bioassay. The results are as follows. 1) ET induced a slow, and very sustained contraction from 10(-9) M. This response is stronger than that of noradrenaline (NA) and continued for 6-12 hours. 2) Under the sustained contraction by the administration of alpha 1 adrenoceptor agonist (methoxamine), ET induced an additional contractile response. 3) The response of ET depended on the concentration of Ca2+. 4) ET did not affect the contraction of vascular smooth muscle which was caused by the electrical stimulation. 5) ET increased the contraction of vascular smooth muscle which was caused by the administration of NA into the bath solution.

Amino Acid Sequence↗

PubMed1991

[Anatomical study on the sphenoidal sinus and petrous apex cells].

Morphological relation between the sphenoidal sinus and the petrous apex cell was studied using HRCT images obtained by 339 adults and 43 infants. The adults were classified into normal group (without chronic otitis media or its surgery) 237 cases, and otitis group (chronic otitis media or its post. op.), 102 cases. The posterior extent of the sphenoidal sinus was evaluated in reference to the carotid canal, and the petrous apex cells were evaluated by their mode of distribution in the apex. In the normal adults, no evident relation was seen between the posterior extent and the mode of distribution. Although adult normal female showed statistically significant better development of the posterior extent, sinus-cell relation was similar between both sexes. The adult normal group and otitis group behave similarly by sinus-cell relation, i.e., no evident relation, although inhibited mode of distribution was seen by otitis group. When the adult and infant were compared, the sinus-cell relation was similar and the posterior extent suffered underdevelopment by infant. The distance, between the posterior extension of the sphenoidal sinus and the apex cell at the medial-anterior tip of the petrous bone, is between 8-16 mm and the contact of the both separated by thin bony wall (less than 0.5 mm) was seen in 3 adult cases (0.9%). Both the sphenoidal sinus and the petrous apex cells are under genetic influence of variable degree, separate genes seem to be at work, thus effecting no evident relation between the two. Apart from the internal or genetic influence, environmental or outer influence also affects the development of the two, less than the genetic.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

[Measurement of parapharyngeal space using CT images].

Parapharyngeal space can be defined as a potential space surrounded by deglutitional and masticator muscles and their covering, superficial and middle layer of deep cervical fascia. It is easily recognized in images provided by modern scanning devices, such as CT and MRI. Parapharyngeal space has traditionally been divided by styloid process and fascia of tensor veli palatini muscle (nasopharyngeal level) or fascia of stylopharyngeus muscle (oropharyngeal level) into two compartments, prestyloid and postsyloid spaces. The latter is often called as carotid space. Prestyloid portion exclusively contains fat tissue, which yields hypoabsorption area in CT films and high density area in MRI. In most of papers in radiological journals, the term of parapharyngeal space is regarded as its prestyloid portion which is clearly identified. Axial CT images of 144 patients without any naso- or oropharyngeal lesions were analyzed. Two reference levels of nasopharynx were adopted for the study. The upper level passes through the plane of fossa of Rosenmuller, and the lower reference level transects soft palate. The following parameters of the space were measured; Length and width of the whole space, length and width of prestyloid fatty space, and furthermore, width of pre- and poststyloid space, that were divided by a imaginary line parallel to the axis of the whole space (the upper level); Length and width of the whole space, length of base and height of a triangle of the prestyloid part (the lower level). While parapharyngeal space was symmetrical in the upper level, the rate of asymmetry amounted to a fourth in the lower level.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1991

Dentigerous cyst of the maxilla and its image diagnosis.

Dentigerous cysts may grow unnoticed to such extensive sizes as to occupy a considerable portion of the maxillary sinus. As they enlarge, the bony walls overlying the cysts thin out giving rise to an egg shell sensation upon palpation. Three cases of such extensive dentigerous cysts were experienced since 1987. These three cases were used to illustrate the advantages and disadvantages of the following imaging techniques in the preoperative evaluation of these cysts, conventional radiographs, sonography, CT, and MRI.

Adult↗

PubMed1990

[Reevaluation of benefit and risk of mass screening for stomach cancer--comparison between X-ray diagnosis and endoscopy as the screening test].

Mass screening for stomach cancer has been widely performed throughout Japan, since stomach cancer is the most important disease among various malignant diseases in Japan. As a screening test, the X-ray diagnosis with barium contrast medium is used and the risk of X-ray exposure must be considered in order to compare with the benefit of the mass screening. We have reported in the previous article in 1977 that the benefit and risk of stomach cancer mass screening become equal at age of 40 y.o. Since then, various conditions with the mass screening of stomach cancer have changed so that reevaluation of the benefit and risk relationship is necessary. Especially the risk coefficient of radiation-induced stomach cancer has been revised drastically in the report of United Nations Scientific Committee on the effects of radiation in 1988. So, in this report, the benefit of mass screening of stomach cancer is defined as the net elongation of average life expectancy due to the life saved, and the risk of the screening is defined as the net shortage of average life expectancy due to the radiation-induced stomach cancer and leukemia. Since the benefit increases rapidly with age and the risk decreases with age, a certain age at which the benefit and risk become identical should be found and under this age the mass screening is not justified to be performed. Assuming X-ray dose equivalent to stomach of 10 mSv and risk coefficient of stomach cancer of 12.6 X 10(-3) Sv-1 from the United Nations report, the critical age is found to be about 35 y.o. for men and women.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

[Benefit-risk analysis of mass screening for lung cancer].

The mass screening of lung cancer has been started with financial support of the Japanese Government from 1987. It should be emphasized, however, that mass screening programs of any kind have to be evaluated by means of benefit-risk analysis and cost-effectiveness analysis. This is the first report on the benefit-risk analysis for mass screening program of lung cancer in Japan. The benefit of the lung cancer mass screening is defined as a net elongation of average life expectancy due to early detection of the cancer. It is calculated as a function of age and sex. While, the risk of the screening program is defined as a net shortage of average life expectancy due to radiation carcinogenesis of leukemia and lung cancer. In the case of radiation carcinogenesis, latent time and plateau period are considered in the calculation of the risk. Since the benefit increases with age and the risk decreases with age for both sexes, one can obtain a certain age at which the benefit and the risk cross. Assuming dose equivalent of lung of 1 mSv and risk coefficient of 15.1 X 10(-3) Sv-1, the crossing ages of men and women are about 42 y.o. and 47 y.o. respectively. We consider that these ages are rather high when chest radiograph is to be used as a screening test. It is recommended that the dose equivalent of lung should be lowered to 0.1 mSv if the mass screening of lung cancer is to be performed.

Adolescent↗

PubMed1990

[Surgical anatomy of the so-called dangerous frontal sinus (Boenninghaus)].

Surgically dangerous type of frontal sinus was first reported by Boenninghaus in 1923. The present study concerns with the types and incidence of the dangerous frontal sinus as investigated by axial scans of HRCT. A total of 286 adult and 33 infant cases was included. The anterior end of the olfactory groove was first classified into three types, i.e., normal type, obliterated type (obliterated by cancellous bone) and dangerous type (with Recessus cristae galli and Torus olfactorius). In the adult, the incidences of these types are, 67.2, 18.5 and 14.3%. In the infant, incidences are 42.4, 51.5 and 6.1%. In the adult, the incidences do not differ in sex and sides. The dangerous type was classified into moderate and severe according to the depth of Recessus cristae galli, those with 1.5-2.9 mm depth are moderate and those over 3.0 mm are severe. The moderate dangerous type was seen in 30 sides and severe in 46 sides. In addition to the depth of Recessus cristae galli, distances from Torus olfactorius to the anterior sinus wall and the frontal skin surface were also included. These distances tend to be larger in male.

Adolescent↗

PubMed1990

[A case of mycotic sphenoidal sinusitis with stone formation].

A 40-year-old white female was seen with the chief complaint of recurrent episodes of severe pulsating occipital headache. The headache was temporarily controlled with the treatment of antibiotics only to recur. Sinus X-ray revealed an increased radio-opacity in the left sphenoidal sinus. The sinus walls showed sclerotic reaction. X-Ray CT demonstrated a small piece of metallic density within the soft-tissue density. Intranasal sphenoidotomy was performed under general anesthesia. A small piece of stone, measuring 3 X 2 X 1.5mm, was found in the sphenoidal sinus, with purulent discharge and caseous concrements. Histopathologic examination of the caseous concrements demonstrated fungal hyphae with branching and septate suggesting Aspergillus sp. Chemical analysis of the stone (3mg dried weight) was done and it consisted of calcium phosphate (88%) and calcium carbonate (12%). Postoperative course for five years was uneventful, and postop. CT confirmed the aerated sphenoidal sinus.

Adult↗

PubMed1990

[The influence of maxillary sinusitis upon the posterior fatty layer--a CT investigation].

CT values were estimated at the fatty layer in contact with the posterior wall of the maxillary sinus in various condition, i.e., normal, sinusitis, postop. sinus, and mucocele. By the unilateral sinusitis (40 cases), CT values obtained by the affected sides were significantly higher than those of the non-affected normal sides. A single maxillary bone was used for experiments to show that the dense++ materials filing the sinus do not affect the CT values of the fatty layer, thus confirming the above clinical data was real and not artifact. In addition, by the mucocele of the maxillary sinus (9 cases) with negligible inflammatory change in the sinus, the CT values of the fatty layer did not show any remarkable increase such as seen by sinusitis. These data lead us to the impression that the increased density is due to the transmitted effects of maxillary sinusitis through the posterior wall. In postop, sinuses (11 cases) with various postop. periods, CT values were slightly higher than those in normal sinuses, suggesting that the sinus infection was under improvement. The enhancement performed by 14 cases (28 sides) showed increased density of the fatty layer, but the increase was similar in both affected and non-affected sinuses. This suggests that the increased rate of circulation at the fatty layer is not the contributory factor to higher CT values. The results described above, combined with the previous reports concerning the bony changes in sinusitis, will lead to the conclusion that the increased CT values at the fatty layer is caused by the direct engagement of the inflammatory conditions in the sinus cavities.

Adipose Tissue↗

PubMed1990

[A simple mathematical model for a quantitative evaluation of mass screening for detection of cancer].

In Japan, where the mass screening of various cancer are actively pursued under the auspices of the Adult Health Promotion Act of the Japanese Government, the incidence rate of various cancers has been undergoing a drastic change since 1960. Cancers of stomach and uterine cervix, which had predominated, are decreasing steadily, whereas lung, colon and breast cancers are rapidly increasing. To provide therapeutic care on the basis of accurate data, the mass screening system must be re-evaluated so as to maintain its effectiveness and efficiency. For this purpose, a simple, deterministic model is proposed to measure the cost-effectiveness of the mass screening quantitatively. The effect of the screening is estimated by the net number of lives that have been saved by the screening, with the final result being shown as the cost require to save one life of a certain age and sex. The model, although only an approximation, fits all kinds of cancers by changing the parameters employed in the mathematical equation, and has been found useful for forecasting the results of future mass screenings for the detection of cancers in Japan.

Humans↗

PubMed1990

[Measurement of myocardial blood flow using N-13 ammonia dynamic PET-theory and methodology].

Positron emission tomography (PET) offers the potential capability of noninvasive measurement of regional myocardial blood flow (RMBF) in man. Because N-13 ammonia exhibits properties which to some extent resemble those of the radioactive microsphere, we developed a first-pass flow method for noninvasive measurement of RMBF. In the present method, RMBF was determined by dividing myocardial activity at time T by arterial input integrated from the injection start to that time, where time T is the endpoint of first circulation of N-13 ammonia. Also in the present method a time-activity curve of left atrium was used as the arterial input function to make the procedure totally noninvasive. To validate the present method, we compared it with the compartment analysis. 5 patients with hypertrophic cardiomyopathy (HCM) and with a considerably thickened ventricular wall, were selected for the comparison between the first-pass flow method and the compartment analysis. The relationship of RMBFs by the two methods was y = 1.8 + 1.097x-0.002037x2 (n = 30, SEE = 5.5), where x (ml/min/100 g) was obtained by the compartment analysis, while y (ml/min/100 g) by the first-pass flow method. The result indicated that both were almost identical in physiological flow range (less than 100 ml/min/100 g), but that the first-pass flow method underestimated RMBF in the higher flow range due to venous leakage of N-13 ammonia. As the conclusion, we could at least measure RMBF of HCM patient in the physiological flow range by the present method. The future extension of the method was discussed.

Ammonia↗

PubMed1989

[Post-operative cyst and orbital walls: a CT image analysis].

A set of coronal CT images obtained by 118 side (109 cases) of post-operative cysts of maxilla, seen from 1982 to 1988, was analyzed as to the orbital wall affections. Coronal images were grouped into five consecutive planes, i.e. the first plane being the one which is 5mm posterior to the nasion, and the other planes in successive orders each being 5mm apart. The orbital walls were classified into inferior, medial, and transition of these two. The orbital wall affections were classified into dehiscence, thinned-out (less than 1mm), and normal. The orbital signs and symptoms (epiphora, pain, asthenopia, visual loss, diplopia, and exophthalmos) were analyzed based upon the questionnaires by patients. The inferior wall affections (dehiscence and thinned-out) were seen most often (57%) at the third plane (2cm posterior to the nasion). The orbital signs and symptoms in general were seen in half of the cases of which 20% were of grave (visual loss, diplopia and exophthalmos). These signs and symptoms were the more often, the more anterior the site of affections located. Grave signs and symptoms were seen at 2 to 2.5cm posterior to the nasion when the orbital floor was affected and the inferior rectus were either pushed up or in direct contact with the cysts.

Adolescent↗

PubMed1989

[The role of high-resolution CT in evaluating disease of the posterior tympanum].

The posterior tympanum consists of several irregular eminences, ridges, and sinuses. These sinuses do not communicate with the mastoid air cell system, and cholesteatoma and/or granulation tissue prefer to fill them. This area cannot be visualized with ease by the usual surgical approach, and is thus quite important for surgeons. Recent developments in high-resolution computed tomography (HRCT) allow more than ever precise identification of subtle changes in the posterior tympanum. Axial HRCT sections provide essential information for the preoperative evaluation of the posterior tympanum. The performance of surgeons has been promoted both in evaluation and treatment planning of patient with suspected posterior tympanic lesions. HRCT findings were compared with the operative findings in 52 patients (54 ears) who had the operation for chronic otitis media. Important findings by HRCT diagnosis of posterior tympanum are as follows: (1) Bone destruction in the posterosuperior part of the tympanic anulus and in the lateral wall of the facial sinus are the important findings for the diagnosis of invasion of cholesteatoma in the posterior tympanum. (2) Similarly important finding is the bone destruction of the pyramidal eminence. This was found in 6 of 9 cases with cholesteatomas extending into the sinus tympani. (3) The soft tissue density in the posterior tympanum does not necessarily indicate pathological processes. Effusion in the posterior tympanum is imaged as soft tissue density, and can not be differentiated from cholesteatoma or granulation by present HRCT.

Adolescent↗

PubMed1989

[Maxillary sinus by waters' view-superimposed structures].

The image of the maxillary sinus obtained by Waters' view contains such superimposed structures as lateral extensions of the sphenoidal sinus and posterior ethmoidal cells. Planimetric evaluations were done for the maxillary sinus itself and the two superimposed sinuses. The medial portion of maxillary sinus is occupied by these two sinuses and the areas covered by these amount to one third of the maxillary sinus' area. To properly interpret the radiolucency of the maxillary sinus, the areas covered by these two sinuses and the areas corresponding to the zygomatic recess should be avoided. The proper radiolucency of the maxillary sinus should be evaluated at the central portion, namely at and around the point where the vertical line passing the inferior orbital canal and the horizontal line passing the foramen rotundum meet each other.

Biometry↗

PubMed1989

[Superstructure of stapes: an analysis by high-resolution computed tomography].

High-resolution Computed Tomography (HRCT) of the temporal bone has now become a routine test for the diagnosis of various temporal bone lesions. Correct assessment of such minute structures as ossicles, especially stapes, is important in the pre-operative HRCT evaluation. On the other hand, analysis for the reliability of HRCT findings has not been done, including the superstructure of the stapes. A retrospectively study was done in order to assess the availability of HRCT findings in axial overlapping scans in 226 ears, with respect to the superstructures of stapes. The study was concerned with the analysis of HRCTs of 148 normal ears, 71 ears of chronic otitis media and 7 ears of ossicular abnormalities. HRCT findings were compared to those of surgeries in pathological cases. The present study revealed that the superstructures of stapes are noted in 70% when the stapes surrounded by air. The major limitations in the proper analysis of stapes by HRCT are partial volume averaging and effects of soft tissue silhouetting, this is especially so when the stapes is surrounded by soft tissue density.

Chronic Disease↗

PubMed1989

[Radiographic anatomy by waters' view on the innominate and Tuber maxillae lines].

Radiographic innominate line and TM line (Tuber maxillae line) which superimpose upon the maxillary sinus by Water's view were classified into four types. These are, no visualization, visualization of the whole length, upper half and lower half, respectively. 324 sides of maxillary sinuses by Waters' were included in this study; of innominate line, no visualization 45%, whole length 17%, upper half 27%, and lower half 11%. Of TM line, no visualization 67%, whole length 9%, upper half 1.5%, and lower half 23%. Of diagnostic significance of the present study, the innominate line, especially the lower half with it's inferior extension, might be confused with bone tips of blow-out fractures, and the TM line, when destroyed, will indicate posterior extension of the lesions. However, These lines only have limited application since about 30 to 50% of them are visualized by Waters' view.

Female↗