Biomedical subjects

T Iinuma

Publications and source records attributed to T Iinuma.

At least 37 records · Page 2Linked to original sources

PubMed1993

An analysis of bone destruction in cholesteatomas by high resolution computed tomography.

Using sectional images of high resolution computed tomography, a quantitative analysis of bone destruction has been undertaken in 73 adult cases with cholesteatoma, 52 having a pars flaccida cholesteatoma (PFC) and 21, a pars tensa cholesteatoma (PTC). These cholesteatomas were further classified into two subtypes: an extended type (cholesteatomas that had extended into the antrum) and a non-extended type (cholesteatomas without an antral extension). Similarly analyzed were 60 cases manifesting chronic otitis media with a central perforation (COM) comparatively. This analysis was performed by means of two-dimensional images and by linear measurement, taken at specific locations in each middle ear cavity. The results revealed that the width of the attic was significantly greater in both the PFC and PTC cases than in the COM cases. Further, a significantly greater distance between the malleus and the lateral wall of the attic was seen in the PFC cases than in the COM cases. In contrast, the distance between the malleus and the medial wall of the attic was significantly greater in the PTC cases than in the COM cases. The extended-type cases had significantly greater distances than did the COM cases with regard to the width of the aditus ad antrum, and the width and anterior-posterior diameter of the antrum. These distances, however, did not significantly differ between the non-extended-type cases and the COM cases. It thus appears that these distances, caused by bone destruction, appear to parallel the extension of the cholesteatoma into the antrum.

Cholesteatoma↗

PubMed1993

Use of B95a cells for isolation of canine distemper virus from clinical cases.

Canine distemper virus (CDV) was readily isolated at high rate with marked cytopathic effect (CPE) in B95a cells, a marmoset lymphoid cell line, from the peripheral blood leukocytes, cerebrospinal fluid cells and brain of dogs. Difference in type of CPE, i.e. syncytium type and round-cell one, among the virus isolates indicate the presence of heterogeneity of virus populations in prevalent CDV. Thus, this cell system is expected to be useful for ecological studies on CDV in the field.

Animals↗

PubMed1993

[The effect of unilateral nasal patency on the contralateral side].

This investigation was designed to verify the possible feed-back mechanism which works to compensate for changes in the nasal volume of one side by the other side. Acoustic rhinometry, with which nasal volume is easily evaluated, was used in this investigation. Acoustic rhinometry was performed at 4 points in time (immediately after, and three, six and nine minutes after, the setting of experimental conditions). This investigation was composed of two studies. In the first study, ten healthy subjects (nine males and one female, 26-49 years of age, mean age 30 years) were evaluated to estimate the effect of decreased unilateral nasal patency upon the other side. In this study, one nasal cavity was occluded with an acryle plug, and the nasal volume of the other side was evaluated by acoustic rhinometry before and after the occlusion. In the second study eight healthy subjects (five males and three females, 24-34 years of age, mean age 29 years) were evaluated to estimate the effect of increased unilateral nasal patency upon the other side. This study covered a period of three days. A small piece of cotton soaked in a vasoconstrictor solution (1/1000 adrenalin or 0.05% naphazolin nitrate) was put in one nasal cavity (the right on the first day, the left on the second day) and the other side was evaluated before and after administration of the solution. On the third day of the control study, a similar piece of cotton soaked in physiological saline solution was put in one nasal cavity, and the other side was evaluated.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1993

[Orbital wall fractures: a comparison of computed tomography and conventional views].

A total of 59 cases of mild facial fractures (simple orbital wall fractures, 34 cases, other facial fractures, 25 cases) with the clinical suspects of orbital wall fractures were evaluated both by conventional views (Waters' and Caldwell views) and coronal CT scans. Conventional views were obtained, as an average, after 4 days and CT after 7 days of injuries. Both the medial wall and the floor were evaluated at two sites, i.e., anterior and posterior. The ethmoid-maxillary plate was also included in the study. The degree of fractures was classified as, no fractures, fractures of discontinuity, dislocation and fragmentation. The coronal CT images in bone window condition was used as reference and the findings were compared between conventional views and CT. The correct diagnosis was obtained as follows: orbital floor (anterior, 78%, posterior, 73%), medial orbital wall (anterior, 72%, posterior, 72%) and ethmoid-maxillary plate (64%). The false positive diagnosis was as follows: orbital floor (anterior only, 13%), medial orbital wall (anterior only, 7%) and ethmoid-maxillary plate (11%). The false negative diagnosis was as follows: orbital floor (anterior, 9%, posterior, 10%), medial orbital wall (anterior, 21%, posterior, 28%) and ethmoid-maxillary plate (21%). The results were compared with those of others in the past.

Adolescent↗

PubMed1993

[An evaluation of nasal patency with acoustic rhinometry--preop. and postop. comparisons].

Changes in nasal patency after nasal surgeries were evaluated with acoustic rhinometry. Fourteen cases (20 sides) were included in the evaluation and the following types of nasal surgery were performed: 2 partial maxillectomies, 11 Caldwell-Luc operations, 4 endonasal ethmoidectomies, 1 endonasal maxillary sinusectomy and 2 septoplasties. The evaluation with acoustic rhinometry was routinely performed on two occasions; the day before and 7-14 days after the surgery. The preop. and postop. results of the evaluations of nasal volume (6.9-14.1 cm by the area-distance curve) and nasal area (averaged areas at 11.0 cm and 13.4 cm by the area-distance curve) were compared. Postop. results in all but one case demonstrated increases in both nasal volume and nasal area, indicating that acoustic rhinometry has practical applications in preop. and postop. evaluations of nasal patency. Three aspects remain to be clarified. The first is the influence of the nasal cycle, which varies considerably at the time of both preop and postop evaluations. The second is the influence of the paranasal sinuses. When the results of cases who had undergone endonasal ethmoidectomy or septoplasty were compared to those who had received partial maxillectomy or Caldwell-Luc operation, the latter showed greater increases in nasal patency, suggesting that the cavities of paranasal sinuses, especially of the maxillary sinus, influence the results of acoustic rhinometry. The third is the size of the anterior entrance of the middle meatus. When the entrance is narrow, the acoustic pulse generated by acoustic rhinometry will not reach up to the paranasal sinuses so that the size of the entrance will again influence the results.(ABSTRACT TRUNCATED AT 250 WORDS)

Acoustics↗

PubMed1993

[Acoustic rhinometry as method for evaluating paranasal sinuses--experimental studies].

The potential application of acoustic rhinometry for evaluating paranasal sinuses was evaluated experimentally. In order to assess the influence of paranasal sinus volume in acoustic rhinometry, three model studies were performed. A tube made of acryle (20 cm in length, 2 cm in diameter) with a side hole was used for the first experiment. In the experiment measuring this tube with acoustic rhinometry, a difference between cases with a side hole (ex. 2 mm in diameter) and these without a side hole was observed. In the former, a more posterior tube position gave rise to an increase in the acoustic curve. In the second experiment, a syringe was was fixed to the side hole of the tube, so as that no leakage of sound wave would occur. A change in the volume of the syringe could be detected by acoustic rhinometry, even with changes as small as 1 ml. In the third experiment, the relationship between the size of the side hole and the volume of the syringe was evaluated. When the volume was less than 20 ml, the value was almost equal to the theoretical value even if the diameter of the side hole was as small as 4 mm. A larger size hole was required when the volume was increased. It was concluded that acoustic rhinometry is of possible value in assessing the paranasal sinuses, if the nasal cavity communicates with the paranasal sinuses via a large opening (e.g. in post-operative cases).

Acoustics↗

PubMed1993

[Evidence for the presence of endothelium-derived relaxing factor in nasal blood vessels].

It has widely been recognized that the vascular endothelium plays an important role in the regulation of vascular tension. Endothelium-derived relaxing factor (EDRF) is a potent vasodilator produced by vascular endothelial cells in response to acetylcholine (ACh) and a variety of other substances. Recent studies have indicated its pharmacological and biochemical effect on vascular smooth muscle tension. The role of the vascular endothelium in the vasodilatory response to ACh stimulation was studied in isolated mucosa from the canine nasal fossa. (1) In the presence of intact endothelium, dose-dependent relaxation was induced by administration of ACh (10(-8)-10(-5)M) under sustained constriction by methoxamine. (2) After endothelial cell injury had been induced by administration of 15-hydroperoxyeicosa tetraenoic acid (15-HPETE), the relaxing response to ACh was abolished with the induction of contraction. (3) Pretreatment with a cyclo-oxygenase inhibitor (indomethacin) did not change the vasodilatory response to ACh stimulation. These results indicate that endothelium is necessary for relaxation in response to ACh, and suggest the presence of EDRF in vessels of the canine nasal mucosa.

Acetylcholine↗

PubMed1992

[Preliminary specification of X-ray CT for lung cancer screening (LSCT) and its evaluation on risk-cost-effectiveness].

In Japan mass screening for lung cancer is widely performed by chest X-ray film of 10 x 10 cm, with sputum cytology for high-risk groups. However, the effectiveness of the present mass screening program for lung cancer has been less than expected, although some date have shown improvement of the survival rate as a result of mass screening. We propose a new X-ray CT method of screening for lung cancer called Lung Cancer Screening CT (LSCT). The preliminary specifications for LSCT are as follows: scan speed is within 10 sec for a 40 cm length with a 1 cm slice thickness, and the absorption dose for lung is less than 1 cGy. A computer-assisted diagnostic system is necessary for image reading. The risk-benefit analysis of LSCT indicates that Japanese men and women over 45 years old can be screened in 1992 and thereafter. The cost per person.year of LSCT screening is estimated to be 1.4 x 10(6) yen for a population incidence rate of 50 x 10(-5) person/year and average life expectancy of 30 years. In 1992 the above condition will be satisfied by men aged 55 years old and above, but not by women of any age. We believe that LSCT should be developed further and tested in the high-risk group of men with an incidence rate of 100 x 10(-5) persons/year or more.

Adult↗

PubMed1992

Comparative sequence analysis and expression of bovine PrP gene in mouse L-929 cells.

A cDNA clone encoding bovine scrapie-associated fibril protein, PrP, from a bovine brain cDNA library and six amplified genomic DNA clones of bovine PrP were characterized. These clones possessed specific characteristics observed in other animal PrP genes. However, the bovine PrP was divided into two types by the number of repeats. One possessed four octapeptide repetitive sequences, like other animal PrP genes, and consisted of 256 amino acids; the other had five such repetitive sequences and 264 amino acids. The amino acid sequence of the former bovine PrP agreed with that of sheep PrP up to the 165th amino acid from the N-terminus. Bovine PrP cDNA introduced into mouse L-929 cells were stably expressed. The expression level of recombinant bovine PrP in the cells judged by immunofluorescence was higher than that of authentic mouse PrP. The recombinant PrP comigrated with authentic bovine PrP in SDS-polyacrylamide gel electrophoresis, suggesting that the recombinant product was fully glycosylated in L-929 cells. Distinct bundles of the intermediate filaments were frequently seen at the perinuclear region of the cells.

Amino Acid Sequence↗

PubMed1992

[Ventilation and passages in the middle ear. A study by HRCT in patients with attic cholesteatoma].

Operative records of 75 patients with acquired attic cholesteatoma were evaluated and compared with preoperative HRCT findings. The cholesteatoma extensions were classified into five groups as follows; Group 1 (cholesteatoma limited to the attic, 9 cases), Group 2 (cholesteatoma occupying both the attic and the aditus, 5 cases), Group 3 (cholesteatoma extending down to the posterior tympanum, also occupying an area as in Group 2, 6 cases), Group 4 (cholesteatoma occupying the attic, the aditus and the mastoid antrum, 14 cases), and Group 5 (cholesteatoma extending down to the posterior tympanum, also occupying an area as in Group 4, 41 cases). Ventilatory conditions, or the existence of soft tissue density, were evaluated by HRCT at such locations as the supratubal recess, mesotympanum, anterior and posterior parts of the tympanic isthmus, epitympanum, and mastoid antrum. Results are as follows. In Group 1, all these locations were aerated with the exception of a few cases. In Group 2, complete opacification was observed in almost all of the antrums. Soft tissue masses involved the anterior and/or posterior parts of the tympanic isthmus in both Groups 3 and 5. In Group 3, the posterior part of tympanic isthmus was less aerated than the anterior part of tympanic isthmus. In Group 5, all locations were filled with soft tissue density except the supratubal recess and the mesotympanum, where some degree of aeration was observed. These results indicate that blockage of the ventilatory passages is not essential for formation of an attic cholesteatoma. Soft tissue density in HRCT is not the cause, but rather, the result of extension of a cholesteatoma.

Adolescent↗

PubMed1992

[The effect of endothelin on neurotransmitter regulation of vascular tension in the nasal mucosa].

A number of studies have emphasized that the sympathetic nervous system in vascular smooth muscle plays an important role in the regulation of vascular tension. Recently, however, it has been suggested that several factors produced in endothelial cells may affect this regulatory mechanism. We have previously reported that endothelin-1 (ET), a novel potent endothelium-derived vasoconstrictor peptide, increased the contraction of nasal vascular smooth muscle which was caused by administration of noradrenaline (NA) into the bath solution. In this report, using canine nasal mucosa, we studied for additional effects of ET upon the vasoactivity of NA, and that of neuropeptide Y (NPY), which coexists with NA in the sympathetic nerve terminal. The results are as follows: 1) Pretreatment with alpha-adrenoceptor antagonists did not affect the vasoconstriction induced by ET. 2) With simultaneous administration of 10(-5)M NA and 10(-9)ET, the contraction peak was maintained for at least 2.5 hours. 3) Pretreatment with 10(-10)M ET did not affect the contraction induced by 2.7 x 10(-7)M NPY. 4) Pretreatment with 2.7 x 10(-8)M NPY did not affect the contraction induced by 10(-8)M ET. These results suggest that ET may enhance and prolong the vasocontractile response mediated by alpha-adrenoceptors, but may not affect the response to NPY.

Animals↗

PubMed1992

[Surgical anatomy of the sphenoid sinus--development and intersinus septum].

High-resolution CT images in axial sections obtained from various otologic lesions were used for morphological studies of the sphenoid sinus. 412 subjects, 224 males and 188 females with an average age of 47.5 years, were included in the study. None of the subjects showed any evidence of sinus lesions. By classifying them into four types, the incidences were: conchal type, 1.2%, and postsellar type, 58.2%, respectively. Of surgically important classification of various septae, the incidences were: transverse, 10.9%, medial, 9.4%, frontal lateral, 14.1%, lateral sagittal, 41.5%, and intersinus, 95.1%, respectively. The intersinus septum, seen in 95.1%, pointed toward the carotid canal in 61.1% (right, 33.1; left, 28.0%). In 80% of the subjects, the sphenoid sinus had extended into the bilateral lesser wings and was in contact with the optic canal.

Adult↗

PubMed1992

[Surgical anatomy of the sphenoid sinus--relationship to the internal carotid artery].

HRCT images in axial sections obtained from various otologic lesions were used for morphological studies of the sphenoid sinus. 412 cases including 224 males and 188 females, with an average age of 47.5 years were included in the study. None of the cases showed any evidence of sinus lesions. The internal carotid artery, at its close connection with the sphenoid sinus, was classified into five portions: I, the second turn; II, between the second and third turns; III, the third turn, IV, between the third and fourth turns, and V, ascending portion of the fourth turn. Protrusion into the sphenoid sinus was seen at I in 30.4% of the cases, at II in 39.8%, at III in 34.3%, at IV in 22.3%, and at V in 11.2%. The second turn, where the internal carotid artery emerges from the carotid canal in the petrous bone and turns upward into the cavernous sinus, showed the highest incidence of the carotid eminence. The incidence of protrusion increases as the sinus grows larger. The average distance between the natural orifice and the carotid canal was 19.3mm on the right and 18.9mm on the left. The distance between the posterior end of the nasal septum and the natural orifice was, on average, 3.6mm on the right and 3.6mm on the left.

Adult↗

PubMed1992

[Comparison of CT and MRI in diagnosis of parapharyngeal tumors].

Recently, the usefulness of CT and MRI in diagnosing parapharyngeal tumors has been established. At the same time, several modalities for these imagings, i.e. plane and enhanced CT, T1, 2 weighted MRI and Gadolinium enhanced MRI, have been developed. We compared the image findings of 12 tumors involving the parapharyngeal space with their operative records. T1 was most suited to diagnosing the sites of origins of tumors because of its superior depiction of the internal carotid artery and parapharyngeal fat. Enhanced CT was also superior in depicting these structures, but in cases where the parapharyngeal fat was diminished, or the parapharyngeal fat had been invaded by malignant tumor, enhanced CT was inferior to T1. The spatial resolution of T2 was poor, T2 was thus not useful in diagnosing the sites of origins of tumors. Because tumor intensity tended to be similar to that of fat in Gadolinium enhanced MRI imaging, Gadolinium was not as useful as T1. In diagnosing the extents of tumors, we examined the depiction of both tumor-fat and tumor-muscle interfaces. With regard to the depiction of the tumor-fat interface, enhanced CT and T1 were most useful. In diagnosing the tumor-muscle interface, Gadolinium enhanced MRI was most suitable. The net result is that MRI is superior to CT.

Adipose Tissue↗

PubMed1992

[On the postoperative mucocele of the maxillary sinus and its simulating cases. A clinical treatise].

The postoperative mucocele of the maxillary sinus typically occurs after 11-15 years after the initial Caldwell-Luc operation with the complaints of swollen and painful cheek. Typical signs and symptoms will be divided into two groups, the one which is associated with expansive lesions and the other with pains along the various branches of the maxillary nerve. In the clinical set-ups, cases with the similar signs and symptoms, and yet lacking definite mucoceles, are often encountered. The present treatise will compare 86 definite cases and 27 simulating cases as to the history, signs and symptoms, various modalities of imaging (CT & MRI), and the possible causes leading to simulating cases. The age at onset, gender, affected side, and period after the initial sinus surgery all showed no differences between the two, i.e., definite and simulating cases. Among signs and symptoms, the definite case showed more of swelling-related matters whereas the simulating case more of pain-related except toothache. The past history of surgeries for the mucoceles on the similar sides to the present lesion is more often seen in the simulating case (64.3%) than in the definite case (18.3%). The findings by imagings in the simulating cases are as follows; obliterated sinus (25.0%), healthy, aerated postop. cavity (35.7%), postop. cavity with mucosal thickening (32.1%), and cyst-like aerated cavity (7.1%). The possible causes leading to the simulating cases are as follows; causes unknown (39.3%), recurrent infection in the postop. cavity (28.6%), dental origin (10.7%), atypical neuralgia (10.7%) and the case shortly after the proceeding sinus surgery (within 12 months, 10.7%).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1992

[Quantitative analysis of cholesteatoma using high resolution computed tomography].

Seventy-three cases of adult cholesteatoma, including 52 cases with pars flaccida type cholesteatoma and 21 with pars tensa type cholesteatoma, were examined using high resolution computed tomography, in both axial (lateral semicircular canal plane) and coronal sections (cochlear, vestibular and antral plane). These cases were classified into two subtypes according with the presence of extension of cholesteatoma into the antrum. Sixty cases with chronic otitis media with central perforation (COM) were also examined as controls. The various locations of the middle ear cavity were measured in term of size with comparisons among pars flaccida type cholesteatoma, pars tensa type cholesteatoma and COM. The results were as follows: 1) The width of the attic was significantly larger in both pars flaccida type and pars tensa type cholesteatoma than in COM. 2) With pars flaccida type cholesteatoma there was a significantly larger distance between the malleus and lateral wall of the attic than with COM. In contrast, the distance between the malleus and medial wall of the attic was significantly larger with pars tensa type cholesteatoma than with COM. 3) With cholesteatoma extending into the antrum, regardless of the type of cholesteatoma, there were significantly larger distances than with COM at the following sites; the width and height of the aditus ad antrum, and the width, height and anterior-posterior diameter of the antrum. However, these distances were not significantly different between cholesteatoma without extension into the antrum and COM. The hitherto demonstrated qualitative impressions of bone destruction in cholesteatoma were quantitatively verified in detail using high resolution computed tomography.

Adolescent↗

PubMed1992

[CT rim effects in various head and neck lesions].

The authors evaluated various head and neck lesions seen from April 1988 through March 1990 both by plain and enhanced CT, examined the incidence of rim effect (or rim enhancement), classified these effects, and discussed underlying mechanisms. Materials consisted of 177 cases including primary tumors (28 benign and 49 malignant cases) and lymphadenopathy associated with malignancy (9 cases, metastatic nodes and malignant lymphomas), inflammatory lesions (20 cases), cystic lesions (12 cases), other lesions (7 cases, jugular thrombosis, carotid atheroma and aural lesions), and 22 cases without abnormal findings. Among the 177 cases, rim effects were observed in 22 cases (12%). These effects were analyzed and classified. The incidences of rim effect according lesion type are as follows; cervical lymphadenopathy associated with malignancy 5/9 (56%), primary tumors 8/77 (10%), inflammatory lesions none, cystic lesions 7/12 (58%), and others 3/7 (43%). The highest incidence was seen with cystic lesions including mucoceles of the paranasal sinuses and cervical cysts. Rim effects were classified as follows; Type 1: cystic pattern, Type 2: parenchymatous pattern, Type 3: vascular pattern and Type 4: others. Type 1 was seen in 15 cases (68%), Type 2 in 3 cases (14%), Type 3 in 3 cases (14%), and Type 4 in 1 case (5%). Type 1 included 6 cystic lesions, 3 malignant lymphadenopathies, 3 benign tumors and others. Type 2 included 2 malignant lymphadenopathies and 1 benign tumor, and Type 3, 2 jugular thromboses and 1 carotid atheroma. There was only one Type 4, a cystic lesion. Of interest is the mode of incidences among cervical lymphadenopathies associated with malignancy.(ABSTRACT TRUNCATED AT 250 WORDS)

Cysts↗

PubMed1991

[Blow-out fractures of the orbit--imaging modalities and therapeutic results].

Thirty-four cases of blow-out fracture were evaluated by high-resolution CT, Hess test for red and green color and synoptophore. The results of these tests were compared with the final outcome of the fractures. The fractures were classified on the basis of the location (floor, medial wall or roof), extent (total, partial or linear) and type of fragments (punched-out or trapdoor). The medial wall type included many cases (33%) with no complaint of double vision, and many cases with a combination of disturbances in ocular mobility in both the horizontal and vertical directions. The floor type showed a low incidence of disturbances in ocular movement in the horizontal directions. Regarding the extent of the fracture, all cases with the total type showed disappearance of double vision within three months. Many of the partial and linear types had a poor outcome. With regard to the type of fragments, all of the trapdoor type cases showed a favorable result with disappearance of double vision within three months. Some of the punched-out type cases, however, showed a poor outcome.

Adolescent↗