Biomedical subjects

I Sando

Publications and source records attributed to I Sando.

At least 73 records · Page 4Linked to original sources

PubMed1992

Three-dimensional anatomy of human Scarpa's ganglion.

Using a computer-aided three-dimensional reconstruction and measurement method, the authors studied the shape and dimensions of Scarpa's ganglion and interrelations of the ganglion to nearby important anatomical structures in 10 normal human temporal bones obtained from 10 individuals of different ages (12 gestational weeks to 72 years). In the postnatal cases, Scarpa's ganglion was shaped like a distorted hourglass. Although the shape of the ganglion varied somewhat among specimens, a superior division, inferior division, and isthmus ganglionaris were distinguishable in each case. Volume of the ganglion was relatively consistent after birth, so that width and height of the ganglion were inversely correlated with each other (linear regression analysis, P less than .05). There seemed to be, however, a possible postnatal increase in the distances from the ganglion to neighboring structures and in the length of the internal auditory canal; these increases were probably the result of postnatal growth of the temporal bone. Moreover, the width of the ganglion in any single specimen was found to correlate significantly positively with the distances from the ganglion to the vestibular end-organs and the length of the internal auditory canal in that specimen (linear regression analysis, P less than .01). This finding suggests that Scarpa's ganglion may be elongated secondary to the elongation of the vestibular nerve due to the growth of the temporal bone. In fetuses, each portion of the ganglion was less clearly identifiable than that portion in postnatal cases. The dimensions of Scarpa's ganglion were found to have reached maturity around the time of birth.

Adolescent↗

PubMed1992

Three-dimensional surgical anatomy for stapes surgery computer-aided reconstruction and measurement.

To define anatomical relationships relevant to stapes surgery, computer-aided three-dimensional reconstruction and measurement were performed on nine normal temporal bones. The mean distance from the inferior portion of the long process of the incus to the center of the oval window was 3.80 mm. The shortest distance from the center of the oval window to the utricular macula, saccular membrane, and macula averaged 1.37, 1.60, and 2.13 mm. Surgery directed posteromedial-superior from the oval window was found to be most dangerous because it would come so close to the utricular macula; a posteromedial-inferior approach was found to be safest. The distance from the inferior margin of the oval window inferiorly to the cochlear duct in the hook portion ranged between 0.58 and 1.29 mm, suggesting that when a drill hole is made on the inferior margin of the oval window to lift up a depressed stapes footplate, the hole should not be greater than 0.5 mm in diameter.

Adolescent↗

PubMed1992

Dark cell pathology in Menière's disease.

The dark cells in the cristae of the semicircular canals were studied histopathologically in 9 temporal bones from individuals with Menière's disease (MD group), 7 temporal bones with endolymphatic hydrops from individuals without a history of Menière's disease (non-MD hydrops group), and 10 normal temporal bones (control group). The density of the dark cells was significantly lower in specimens in the MD group versus the non-MD hydrops group (Wilcoxon's ranking test, t = 90.5, p less than 0.01) and control group (Wilcoxon's ranking test, t = 50.0, p less than 0.01), and many of the dark cells were found to be abnormal in the specimens from the MD group. The difference in dark cell density between the non-MD hydrops group and control group, however, was not significant (Wilcoxon's ranking test, t = 75.0), and few cells in these groups were abnormal. It is speculated that the differences in density and the abnormalities in dark cell morphology might be either factors in the etiology of endolymphatic hydrops or results of Menière's disease. Other, unknown, factors must be postulated to produce endolymphatic hydrops in ears with hydrops but without MD.

Adult↗

PubMed1992

Computer-aided three-dimensional reconstruction and measurement of microfissures.

The spatial anatomy of microfissures in the round and oval window areas was investigated in 24 randomly selected normal human temporal bones by our computer-aided three-dimensional reconstruction and measurement method. Microfissures that communicated with the middle ear surface in the round window area were seen in 21 cases (87%) and were located on the posteromediosuperior aspect of the round window niche; whereas microfissures in the oval window area, seen in seven cases (29%), were located at various sites, but mostly in the area below the oval window. Of the 21 microfissures seen in the round window niche, only four were found to be visible through the aperture of the round window niche when viewed from the lateral direction. The mean lengths of the microfissures seen on the middle ear surface in the round and oval window areas were 0.95 +/- 0.66 mm and 0.74 +/- 0.44 mm, respectively. The microfissures in the round window area were significantly longer in individuals 20 years of age and older, than in those less than 20 years (Wilcoxon test, t = 21.5, p less than 0.01); this tendency for microfissures to be longer in older subjects was also found for microfissures in the oval window area. The possible clinical and pathologic significance of these results is discussed.

Adolescent↗

PubMed1991

Vestibular aqueduct in Menière's disease and non-Menière's disease with endolymphatic hydrops: a computer aided volumetric study.

The volume of the vestibular aqueduct was studied by a computer-aided volumetric method in 9 temporal bones with endolymphatic hydrops from individuals with Menière's disease (MD), 7 temporal bones with endolymphatic hydrops from individuals without a history of Meniere's disease (non-MD hydrops), and 10 normal temporal bones (controls) to investigate the cause of endolymphatic hydrops in both MD and non-MD hydrops. A hypoplastic vestibular aqueduct was found significantly more often in the MD group than in either the non-MD hydrops group (chi 2-test, chi 2 = 4.063, p less than 0.05) or the control group (chi 2-test, chi 2 = 6.363, p less than 0.05). The difference in volume between the non-MD hydrops group and the control group was not significant. It is speculated that a small vestibular aqueduct (presumably containing a small endolymphatic sac) might be a predisposing factor in Menière's disease. In contrast, in non-MD hydrops, there seems to be no correlation of endolymphatic hydrops with a hypoplastic vestibular aqueduct and endolymphatic sac.

Adult↗

PubMed1991

Insertion of the tensor veli palatini muscle into the eustachian tube cartilage in cleft palate cases.

Differences in insertion of the tensor veli palatini muscle (TVPM) into the lateral lamina of the eustachian tube (ET) cartilage between cleft palate (CP) cases and controls were investigated histologically. Thirty temporal bones with entire ETs were studied: 10 from individuals with CP and 20 controls. The ratio of the length of the ET cartilage with insertion of the TVPM to its total length from the nasopharyngeal end to near the tubal isthmus was calculated in all 30 cases. In all 20 controls, but in only 6 of 10 CP cases, the TVPM inserted into the lateral lamina of the ET cartilage at its tip portion (chi 2 test, p less than .025). The ratio was significantly smaller in CP cases (0.178 +/- 0.172) than in controls (0.419 +/- 0.120) (t = 4.305, p less than .001). We believe that abnormal insertion of the TVPM into the ET cartilage is one of the causes of the functional obstruction of the ET that contributes to the frequent bouts of otitis media experienced by those with cleft palate.

Abnormalities, Multiple↗

PubMed1991

Abnormalities of lateral cartilaginous lamina and lumen of eustachian tube in cases of cleft palate.

Development of the lateral lamina (LL) of the eustachian tube (ET) cartilage was investigated in cleft palate (CP) cases and controls by measuring the areas of the LL and medial lamina (ML) of the ET cartilage in histologic cross section, and comparing the ratio of the area of LL to that of ML (LL/ML) in CP cases and controls. The degree to which the ET lumen appeared straight or C-shaped in cross section was also measured. Thirty temporal bones with the entire ET--10 CP cases and 20 controls--were studied. The ratio of the areas of the ET cartilage was significantly smaller (t = 2.903, p less than .01) and the curvature of the ET lumen was significantly less (t = 2.080, p less than .05; chi 2 = 3.936, p less than .05) in CP cases than in controls. In addition, in all 30 CP cases and controls, the ratio of the areas of cartilage was significantly less in specimens with straight ET lumens than in those with C-shaped lumens (t = 2.713, p less than .02). The results appear to show that the ET cartilages and lumens are anomalous in CP cases. These anomalies are considered to be important factors in active ventilatory dysfunction of the ET.

Cartilage↗

PubMed1991

Sexual dimorphism and development of the human cochlea. Computer 3-D measurement.

The length of the cochlear turns was measured in 9 pairs of temporal bones from age-matched male and female individuals (1 day to 76 years old), using a computer-aided three-dimensional reconstruction and measurement method. The mean cochlear length was significantly longer (Two-way analysis of variance, F = 31.87, d.f. = 1, p less than 0.01) in males (37.1 +/- 1.6 mm) than in females (32.3 +/- 1.8 mm), whereas it did not vary with postnatal age in either sex. Sexually dimorphic cochlear length may pose a new issue in auditory physiology in man. The lack of postnatal elongation also indicates that length of the cochlea becomes close to its maximum during fetal life.

Aging↗

PubMed1991

Update on functional anatomy and pathology of human eustachian tube related to otitis media with effusion.

New anatomic and histopathologic information regarding the eustachian tube and its surrounding structure as well as possible mechanisms of opening and closing function and dysfunction are discussed in this article. In the past two decades, much light has been shed on the relationship between anomalies of the eustachian tube and the pathogenesis of otitis media with effusion. Now that a technique for obtaining specimens for any histopathologic study that includes the temporal bone as well as the eustachian tube is available, it is hoped that, by harvesting and examining a large number of such specimens, more information will be gained about the relation between eustachian tube pathology and eustachian tube dysfunction, particularly as it relates to otitis media effusion. Only in this way can the clinical management of otitis media be improved.

Adult↗

PubMed1990

Temporal bone histopathologic findings in Alagille's syndrome.

Six temporal bones obtained from four individuals with Alagille's syndrome, aged 4 months and 3, 6, and 7 years, were studied histopathologically. The external auditory canals and tympanic membranes were normal. Although the stapes, the interossicular joints, and the subarcuate fossae were slightly underdeveloped in the majority of cases, the other structures in the middle ear were almost normal. However, severe anomalies were observed in structures in the inner ear. In all cases, both the bony and membranous structures of the posterior semicircular canal were partially or totally absent, and, in three ears, those of the anterior semicircular canal were also partially absent; the lateral semicircular canal, however, was normal in all cases. The cochlea was observed to be shortened in only one case.

Abnormalities, Multiple↗

PubMed1990

Histopathologic study of otitis media in individuals with head and neck tumors.

Five temporal bones, each including the eustachian tube, were obtained from five adults with advanced malignant tumors of the head and neck. The specimens were from the side on which the tumor had occurred. Otitis media had been detected clinically in two cases, and was detected histopathologically in the other three. We discuss the possibility that otitis media might have been caused by tumor invasion of the paratubal area, by postoperative inflammation in the nasopharynx, or by an inflammatory reaction of tubal structures to radiotherapy, or that these conditions may have coexisted.

Adult↗

PubMed1990

Histologic study of eustachian tube cartilage with and without congenital anomalies: a preliminary study.

We investigated histopathologically the development of the eustachian tube (ET) cartilage at a cellular level in individuals with and without congenital anomalies. Fourteen specimens were obtained from 14 individuals ranging in age from 24 weeks' gestation to 3 years who had cleft palate or trisomy 21 (Down) syndrome; the 49 specimens in the nonanomaly (control) group were from 49 individuals ranging from 26 weeks' gestation to 85 years of age. All temporal bone specimens included the ET and its accessory structures, and all were processed and stained with hematoxylin and eosin for histologic study in a routine manner. The number of cartilage cells in the midcartilaginous portion of the ET was determined by light microscopy. In all groups, cartilage cell density of the ET decreased with increasing age. However, cell density tended to be higher at all ages for individuals with cleft palate and microtia versus controls, and tended to be lower at all ages for individuals with Down syndrome.

Adolescent↗

PubMed1990

Otitis media in association with various congenital diseases. Preliminary study.

We studied temporal bone histopathology to obtain clues as to the role of eustachian tube (ET) disease in the pathogenesis of otitis media (OM) in patients with congenital anomalies. Thirteen temporal bones obtained from 13 individuals with various congenital anomalies were used. We looked in particular at severity of inflammation in the middle ear (ME) and ET, and at deformity of the ET cartilage. Evidence of OM was found in all the temporal bones. The ETs consistently showed a moderate degree of inflammation but without any particular correlation with the severity of ME inflammation. Deformity of the ET cartilage was present in six cases (46.2%), representing three cases of cleft palate and three of other congenital anomalies. Because the deformity of ET cartilage tended to be associated with more severe OM, we consider this cartilage deformity to be an important cause of tubal dysfunction, and thus of the high incidence of OM among individuals with congenital ear anomalies.

Child, Preschool↗

PubMed1990

Computer-aided 3-D temporal bone anatomy for cochlear implant surgery.

To define anatomical relationships important in cochlear implantation, computer-aided three-dimensional reconstruction and measurement of middle and inner ear structures in six normal temporal bones were performed. Our findings were as follows: 1. When viewed from the posterior hypotympanotomy (facial recess) approach, the inferior 10% to 30% of the round window (RW) membrane was visible in only half the cases. 2. The most inferior portion of the basal turn of the scala tympani was not only inferior but also slightly anteriorly behind the RW membrane in more than half the cases. 3. The shortest distances from the aperture of the RW niche and from the margin of the RW to the stapes head were 2.38 +/- 0.33 and 2.15 +/- 0.22 mm, respectively. 4. The distance between the RW and the most inferior portion of the basal turn scala tympani was 5.15 +/- 0.34 mm. 5. The direction of the electrode advancement lay at a sharp angle to the inferior part of the RW (mean 31.9 +/- 3.6 degrees). 6. The direction from the RW to the most inferior portion of the basal turn scala tympani lay 16.0 +/- 5.3 degrees anteroinferior to the direction of the advancement of the electrode to the RW. 7. The distance between the margin of the RW and the basilar membrane of the cochlea was 0.58 +/- 0.10 mm at the superior aspect of the RW, and was 1.23 +/- 0.12 mm at the lateral aspect of the RW. 8. Dissecting away less than 1 mm (mean 0.7 +/- 0.27 mm) of the RW margin inferiorly or inferolaterally was enough to permit straight insertion of the electrode in most cases.

Adolescent↗

PubMed1990

Computer-aided three-dimensional reconstruction and measurement for multiple-electrode cochlear implant.

To assist surgeons in performing multiple-electrode cochlear implant operations, the spatial relations between middle and inner ear structures in six normal temporal bones were studied using the computer-aided 3-D reconstruction method. When viewed through the external auditory canal, the approach used for electrode insertion, and the relation of the malleus to the helicotrema or the scala vestibuli in the second turn of the cochlea were found to vary considerably. In contrast, when viewed from the same transmeatal approach, both the direction and the distance from the stapes footplate to the scala vestibuli of the second turn of the cochlea and helicotrema were found to be quite stable. We concluded that the stapes footplate was a better landmark than the malleus when approaching the helicotrema and scala vestibuli of the second turn of the cochlea during multiple-electrode cochlear implant surgery.

Adolescent↗

PubMed1989

Computer-aided three-dimensional reconstruction: a method of measuring temporal bone structures including the length of the cochlea.

To visualize the three-dimensional (3-D) shapes of structures in the temporal bone from histologic sections, we developed computer software to create computer-generated 3-D images from two-dimensional (2-D) materials. Using those images, we have been able to measure these structures in three dimensions. This means that quantitative 3-D measurements can be performed regardless of the angle at which the specimen was cut. This report describes this method for 3-D reconstruction and measurement and discusses its implications. For instance, in addition to showing the 3-D shape of the cochlea from different angles, we have been able to measure the length of the cochlea and have shown that measurements made by use of the conventional 2-D graphic reconstruction method can be distorted considerably by variations in cutting angle of the specimen.

Cochlea↗

PubMed1989

Congenital anomalies of the eustachian tube in Down syndrome. Histopathologic case report.

Congenital anomalies of the eustachian tube (ET) that may play an important role in the cause of otitis media with effusion should be investigated histopathologically. One such anomaly, which has not been thoroughly investigated to date, is that accompanying Down syndrome. This report describes histopathologic findings in a temporal bone obtained from a 26-weeks' gestation male fetus with Down syndrome. As compared to a control specimen, its ET was extremely small, mostly collapsed in the midcartilaginous, isthmus, and tympanic portions, and had poorly developed lateral cartilage in the midcartilaginous portion. This is the first case report of such ET anomalies, which appear to be due to an insult to the ET that occurs earlier in fetal life than the 16th gestational week. This insult is possibly a causative factor in postnatal ET dysfunction.

Down Syndrome↗

PubMed1989

Computer-aided three-dimensional reconstruction and measurement of the round window and its membrane.

This study was performed to clarify the complex three-dimensional shape of the round window and its membrane, and to measure these structures by using the computer-aided three-dimensional reconstruction method we developed. The equipment used included a personal computer, a high-resolution, 14-inch color monitor, and a digitizer. Materials consisted of five normal temporal bones obtained from five individuals with negative otologic histories who had been 5 months and 14, 15, 18, and 59 years old at death. Round window membranes were found to be convex to the middle ear side when viewed in the coronal plane, but to be concave when viewed in the sagittal plane; thus the membrane in most cases seemed to be shaped like a saddle, tapered toward the vestibular end. The average maximal diameter, sagittal length, horizontal width, and surface area of the round window were 2.32 +/- 0.19 mm, 2.08 +/- 0.22 mm, 1.76 +/- 0.10 mm, and 2.70 +/- 0.43 mm2, respectively. The average surface area of the round window membrane was 2.98 +/- 0.43 mm2.

Adolescent↗