Kenji Takasaki

University of Pittsburgh, Pittsburgh, PA, USA

Are you Kenji Takasaki?

Claim your profile

Publications (7)8.04 Total impact

  • Article: Histopathological Changes of the Eustachian Tube Cartilage and the Tensor Veli Palatini Muscle With Aging
    [show abstract] [hide abstract]
    ABSTRACT: Objectives: The eustachian tube (ET) and the tensor veli palatini muscle (TVPM) are thought to play an important role in ventilatory function. Calcification of the ET cartilage and the replacement of TVPM by fat tissue are often observed histologically in elderly patients. To our knowledge, however, there are no quantitative studies of these pathological findings in relation to age.Study Design: The calcification of the ET cartilage and the atrophy of the TVPM in 36 normal human temporal bones obtained from 36 individuals with ages ranging from 2 days to 88 years were investigated.Methods: The number of calcified chondrocytes in the midportion of the ET cartilage was quantified as the average number of cells per square millimeter. Atrophy of the TVPM was evaluated at the midportion of the site where the TVPM is attached to the tip of lateral lamina of ET cartilage. A grade of 0, 1, 2, 3, or 4 was assessed for each section, which indicated approximately 0% to 5%, 5% to 30%, 30% to 70%, 70% to 95%, or 95% to 100% of the TVPM replacement by fat tissue, respectively.Results: A statistically significant correlation was found between the number of the calcified cells and aging (P < .001). A statistically significant correlation was also found between the degree of the atrophy of TVPM and aging (P < .001).Conclusions: The calcification of the ET cartilage and the atrophy of the TVPM are closely associated with aging. Therefore, it is suggested that these two findings may be a predisposing factor for ET dysfunction in elderly adults.
    The Laryngoscope 01/2009; 109(10):1679 - 1683. · 1.75 Impact Factor
  • Article: Difference in attachment of the tensor veli palatini muscle to the eustachian tube cartilage with age.
    [show abstract] [hide abstract]
    ABSTRACT: To test a hypothesis that ventilation of the eustachian tube (ET) varies with age, we investigated the relationship between age and the attachment of the tensor veli palatini muscle (TVPM) to the lateral lamina of the ET cartilage in 12 normal human temporal bones obtained from individuals 3 months to 81 years old. We used computer-aided 3-dimensional reconstruction and measurement methods. We found that the length of the TVPM attachment and its ratio to the length of the ET, especially that of the cartilaginous portion of the ET, increases with age from infancy to adulthood, and decreases with age from young adulthood to later life. These findings are thought to be related to postnatal development and aging. The possibility of differences in ventilation function with age is discussed.
    The Annals of otology, rhinology, and laryngology 06/2003; 112(5):439-43. · 1.05 Impact Factor
  • Article: Cellular proliferation of mucosa-associated lymphoid tissue with otitis media: a preliminary study.
    [show abstract] [hide abstract]
    ABSTRACT: Histopathologic and immunohistochemical analyses were used to investigate the cellular proliferation of mucosa-associated lymphoid tissue (MALT) in human temporal bones with and without evidence of otitis media (OM). Anti-proliferating cell nuclear antigen (PCNA) antibody (clone PC10) was applied after the antigen retrieval procedure. Positive PCNA expression was observed in temporal bones that had been stored for 10 to 31 years in 80% ethanol. In specimens with purulent OM, the MALT had faint germinal centers (GCs). Positive PCNA expression in the MALT was moderate and scattered. In specimens with mucous OM, the MALT had complete GCs. Positive PCNA expression in the MALT was moderate to strong, and the distribution of PCNA-positive cells was associated predominantly in the GCs, the mucosal epithelial layer, and/or the subepithelial layer. In specimens with serous OM, the MALT also had complete GCs. However, the PCNA expression was weak and scattered, and appeared to be similar to that of the MALT in the temporal bones without OM. These results indicate that the cellular proliferation of MALT in the temporal bone might reflect the activity that produces secretory IgA against invasion of foreign antigens. However, further studies are needed to elucidate whether the PCNA expression within MALT in the eustachian tube and middle ear is associated with a mucosal immune response to inflammation as in OM.
    The Annals of otology, rhinology, and laryngology 11/2002; 111(10):926-32. · 1.05 Impact Factor
  • Article: Functional anatomy of the tensor veli palatini muscle and Ostmann's fatty tissue.
    [show abstract] [hide abstract]
    ABSTRACT: This study examined morphological features of the tensor veli palatini muscle (TVPM) and Ostmann's fatty tissue that may be important for eustachian tube (ET) ventilation. Histologic sections through the midcartilaginous ET from 17 human temporal bone-ET specimens (age range. 3 months to 88 years) were used to assess 1) the presence or absence of attachment of the TVPM fibers to either the perichondrium of the ET cartilage lateral lamina (LL) or a tendinous membrane along the medial margin of the TVPM, 2) the angular relationship between the TVPM fibers and the vertical axis of the ET lumen, and 3) the location of the TVPM and Ostmann's fatty tissue. The TVPM fibers were attached to the LL perichondrium in 14 cases; an attachment was absent in 3 cases because of fatty atrophy of the TVPM. However, the TVPM fibers were inserted into the tendonlike membrane in all cases. The angle of insertion of TVPM fibers into the membrane was significantly more acute (relative to the vertical ET axis) in the inferior aspect than in the superior aspect of the membrane both in young children (3 months to 4 years; mean +/- SD, 39.0 degrees +/- 15.1 degrees superiorly to 23.8 degrees +/- 17.0 degrees inferiorly) and in older subjects (8 to 88 years, 30.4 degrees +/- 11.6 degrees superiorly to 15.7 degrees +/- 11.2 degrees inferiorly; t-test, p < .001). The location of Ostmann's fatty tissue accompanied the TVPM throughout the cartilaginous ET. These data suggest that contraction of the TVPM moves the LL inferolaterally to open the superior aspect more than the inferior aspect of the lumen and that Ostmann's fatty tissue will limit the opening of the ET lumen, especially that of its inferior aspect.
    The Annals of otology, rhinology, and laryngology 11/2002; 111(11):1045-9. · 1.05 Impact Factor
  • Article: Postnatal development of static volume of the eustachian tube lumen. A computer-aided three-dimensional reconstruction and measurement study.
    [show abstract] [hide abstract]
    ABSTRACT: Eleven human temporal bone-eustachian tube (ET) specimens obtained from 11 individuals (ages, 3 months to 88 years) were studied to investigate the static volume of the ET lumen. The volumes were measured by computer-aided 3-dimensional reconstruction and measurement methods. Four of the 11 individuals were children, and the remaining 7 were adults. The total volume of the ET lumen was significantly larger in the adults than in the children (p < .01). This difference was produced by significant growth of the volume of the cartilaginous and junctional portions (p < .01). The lumen of the bony portion, by contrast, did not change with age. Increased volume of the ET lumen, especially of the cartilaginous and junctional portions, would be expected to increase both ventilation and clearance. Therefore, the small volume of ET lumen of the cartilaginous and junctional portions in children may be a predisposing factor for otitis media.
    The Annals of otology, rhinology, and laryngology 09/2002; 111(9):832-5. · 1.05 Impact Factor
  • Article: Functional anatomy of levator veli palatini muscle and tensor veli palatini muscle in association with eustachian tube cartilage.
    [show abstract] [hide abstract]
    ABSTRACT: The anatomic relationships among the levator veli palatini muscle (LVPM), the tensor veli palatini muscle (TVPM), and the eustachian tube (ET) cartilage were investigated by computer-aided 3-dimensional reconstruction and measurement methods. The study used 13 normal temporal bone-ET specimens obtained from 13 individuals (range of age at death, 3 months to 88 years). This study revealed several anatomic features of the anterior cartilaginous portion of the ET. First, the LVPM is always located inferolateral to the inferior margin of the medial lamina (ML) of the ET cartilage. Second, the LVPM has a large cross-sectional area throughout the extent of the anterior cartilaginous portion of the ET. Third, although the LVPM lies close to the ML of the ET cartilage (0.44+/-0.16 mm in children and 1.02+/-0.58 mm in adults), there is no region of attachment. Finally, the TVPM is not attached to the lateral lamina (LL) of the ET cartilage of the anterior quarter of the cartilaginous portion. Accordingly, it could be assumed that the most anterior cartilaginous portion of the ET is opened primarily by the contraction of the LVPM, which causes a superior-medial rotation of the ML. Furthermore, since the contraction time of the LVPM is reported to be longer than that of the TVPM, the anterior cartilaginous portions of the ET may remain open, even after the middle to posterior cartilaginous portions are closed after relaxation of the TVPM. This process would produce a pumping action of the ET in the direction from the middle ear to the pharyngeal side. The pumping function may be beneficial to clearance of the middle ear.
    The Annals of otology, rhinology, and laryngology 07/2002; 111(6):530-6. · 1.05 Impact Factor
  • Article: Estimated locations of the narrowest portion of the eustachian tube lumen during closed and open states.
    The Annals of otology, rhinology, and laryngology 04/2002; 111(3 Pt 1):255-60. · 1.05 Impact Factor