Biomedical subjects

Norimoto Gotoh

Publications and source records attributed to Norimoto Gotoh.

6 recordsLinked to original sources

PubMed2006

Three-dimensional imaging of macular holes with high-speed optical coherence tomography.

OBJECTIVE: To demonstrate the advantages of 3-dimensional imaging of macular hole pathology using new-generation high-speed optical coherence tomography (OCT). DESIGN: Prospective observational case series. PARTICIPANTS: Twenty-one eyes from 20 consecutive patients diagnosed with a macular hole. METHODS: A prototype high-speed OCT system was built based on a Fourier-domain OCT (FD OCT) technology for patient examination. The system has achieved sensitivity of approximately 98 decibels, axial resolution of approximately 4.3 mum in tissue, and an acquisition rate of approximately 18,700 axial scans per second. Three-dimensional imaging of macular hole pathology was performed based on a raster scan protocol consisting of 256x256 axial scans. All patients were imaged with 3-dimensional OCT, Stratus OCT, and OCT Ophthalmoscope C7. MAIN OUTCOME MEASURES: Images of macular hole pathologies obtained by 3-dimensional OCT and standard OCT instruments. RESULTS: The 3-dimensional OCT imaging successfully generated realistic 3-dimensional images of the vitreofoveal interface and intraretinal microstructures associated with a macular hole. The 3-dimensional overview of the vitreofoveal interface was helpful in gaining an immediate understanding of the dynamic interactions of the vitreous and fovea. Observations of consecutive en face images in combination with conventional longitudinal images and of cross-sectional images in combination with sectioned volume images enabled identification of intraretinal microstructures and their 3-dimensional extension associated with a macular hole, such as subfoveal structural changes after vitreous traction, connection of the flap to intraretinal structures, the external limiting membrane (ELM) and its disruption, and elevated photoreceptor inner and outer segments delineated by the ELM. The appearance of inner-wall images of a macular hole produced by photoreceptor inner and outer segment backreflection varied throughout macular hole stages. CONCLUSIONS: Three-dimensional imaging of macular holes with high-speed OCT based on FD OCT technology offers 3-dimensional overviews that facilitate understanding of the abnormalities in the vitreofoveal interface. It also provides consecutive orthogonal images that allow much more precise and minute observation of 3-dimensionally extending intraretinal structural changes associated with a macular hole than conventional OCT imaging, especially in the photoreceptor inner and outer segments.

Aged↗

PubMed2006

Pigment epithelial detachment in polypoidal choroidal vasculopathy.

PURPOSE: To study the morphological features of serosanguineous pigment epithelial detachments (PEDs) with accompanying polypoidal lesions in eyes with polypoidal choroidal vasculopathy (PCV). DESIGN: Retrospective observational case series. METHODS: For this observational case study, we retrospectively reviewed 93 consecutive eyes of 85 patients with PCV. The lesions in eyes with PCV were examined with indocyanine green angiography (IA) and optical coherence tomography (OCT). RESULTS: Of 93 eyes with PCV, 51 eyes (55%) had serous or hemorrhagic PEDs. Of these 51 eyes, a notch in the PED was found in 27 eyes (53%) by angiography, most of which showed polypoidal lesions by IA that corresponded in location to the notch observed by angiography. Polypoidal lesions were detected outside the PED in one eye (2%), at the margin of the PED in 33 eyes (65%), and inside the PED in 12 eyes (24%). OCT revealed that PED had a notch observed tomographically in 29 eyes (57%), most of which corresponded in location to polypoidal lesions seen by IA. In eight eyes, polypoidal lesions, which were adherent to the inner surface of the serous PED, appeared to be detached from the Bruch membrane and the choroid. CONCLUSIONS: Polypoidal lesions are located at the margin of PED and make a notch in the accompanying PED that is visible by angiography and tomographically. When the polypoidal lesions have increased exudate, the fluid from the lesions infiltrates under the polypoidal lesions themselves, which results in the lesions detaching from the Bruch membrane and appearing to be located inside the PED.

Aged↗

PubMed2006

No association between complement factor H gene polymorphism and exudative age-related macular degeneration in Japanese.

Age-related macular degeneration (ARMD) is the leading cause of blindness in the elderly population not only Western but also Asian industrial countries. In Caucasian, a polymorphism of the complement factor H gene (CFH), the C allele of rs1061170 (Y402H), was established as the first strong genetic factor for excursively exudative type of ARMD. In this study, we performed an extensive sequencing of the 22 exons in the CFH gene by recruiting 146 exudative ARMD patients and 105 normal controls of Japanese origin and identified 61 polymorphisms. We found that the frequency of the C allele of rs1061170 (Y402H) is much lower (0.04) in Japanese controls than in Caucasians (0.45). No case disease susceptibility to exudative ARMD was noted for rs1061170 (Y402H) (chi (2) = 3.19, P (corr) = 0.423), or other 12 single nucleotide polymorphisms (SNPs) whose frequency is greater than 0.05. When haplotypes were inferred for 13 SNPs (these 12 SNPs with a frequency greater than 0.05 and rs1061170), three haplotypes whose pattern was similar to those in Caucasians were identified but with substantial difference in frequency. Again we failed to identify genetic association between Japanese exudative ARMD and any of the haplotypes including the J1 haplotype which was shown to be susceptible to ARMD in Caucasians (chi (2 )=( )3.92, P (corr) = 0.157). CFH does not appear to be a primary hereditary contributor to ARMD in Japanese. The absence of CFH contribution to ARMD in Japanese may correlate with the findings in ethnic differences of ARMD phenotypes.

Age Factors↗

PubMed2006

Polypoidal choroidal vasculopathy with choroidal vascular hyperpermeability.

PURPOSE: To describe the incidence and clinical characteristics of polypoidal choroidal vasculopathy (PCV) associated with choroidal vascular hyperpermeability. DESIGN: Retrospective observational case series. METHODS: We reviewed the medical records of 122 consecutive eyes with PCV and 106 consecutive eyes with exudative age-related macular degeneration (AMD). Fluorescein angiography and indocyanine green (ICG) angiography were performed using a confocal scanning laser system. In the midphase of ICG angiography, we evaluated choroidal vascular hyperpermeability, which is recognized as one of the characteristic findings in central serous chorioretinopathy (CSC). Choroidal vascular hyperpermeability appeared as multifocal patchy areas of hyperfluorescence with blurred margins within the choroid that increased in intensity with time after injection of the dye. RESULTS: Of 122 eyes with PCV, 12 (9.8%) eyes of 10 patients exhibited multifocal choroidal hyperfluorescence in the midphase of ICG angiography, whereas two (1.9%) of 106 eyes with exudative AMD showed a similar appearance (P = .013). Of the 12 eyes in 10 patients with PCV that demonstrated multifocal choroidal hyperfluorescence, we also noted that the early phase of ICG angiography showed choroidal filling delay in seven eyes (58%) and venous dilation in 12 eyes (100%). Four of these 12 eyes (33%) had a medical history of CSC, and nine (90%) of the 10 patients revealed multifocal choroidal hyperfluorescence bilaterally. CONCLUSIONS: Multifocal choroidal hyperfluorescence seen by ICG angiography occurs more frequently in eyes with PCV than in those with AMD. Choroidal vascular hyperpermeability, reportedly a characteristic finding in CSC, might be one of the risk factors of PCV.

Aged↗

PubMed2004

Apolipoprotein E polymorphisms in Japanese patients with polypoidal choroidal vasculopathy and exudative age-related macular degeneration.

PURPOSE: To study the genotypes, allelic frequencies, and polymorphisms of apolipoprotein E (Apo E) in unrelated Japanese patients with polypoidal choroidal vasculopathy (PCV) or exudative age-related macular degeneration (AMD) and control subjects without macular degeneration. DESIGN: Cross-sectional study. METHODS: Blood samples from 225 subjects older than 50 years were used. The 225 subjects included 58 patients with PCV, 85 with AMD, and 82 without macular degeneration. Coding exons of the Apo E gene were amplified by polymerase chain reaction, and the DNA sequences were determined by direct sequencing with an automated sequencer. RESULTS: Apo E epsilon3/epsilon3 was the most frequent genotype with a prevalence of 79.3% in PCV patients, 76.5% in AMD patients, and 67.1% in the control subjects. However, the differences in the percentages were not statistically significant among the three groups. The most frequently found allele in the three groups was epsilon3. Patients with PCV and AMD were less likely to have epsilon2 and epsilon4 than the control subjects, but the differences were not statistically significant. Five minor Apo E single nucleotide polymorphisms, including epsilon5 and epsilon7, were found. CONCLUSION: Japanese patients with PCV and AMD were less likely to have epsilon2 and epsilon4 polymorphisms, but the differences from the normals were not statistically significant for the Apo E genotypes and allelic frequencies.

Aged↗

PubMed2002

Role of PTB-like protein, a neuronal RNA-binding protein, during the differentiation of PC12 cells.

PTB-like protein (PTBLP) is a new homologue of pyrimidine tract binding protein (PTB), and has been cloned as a possible autoantigen in cancer-associated retinopathy. PTBLP has two functional domains, the nuclear localization signal and the RNA recognition motifs (RRMs). Full-length PTBLP (PTBLP-L) has four RRMs, and its alternative splicing product (PTBLP-S) lacks the third and fourth RRMs. Although PTBLPs are expressed in neuronal tissues, the function of PTBLPs has not been determined. We have studed whether PTBLP plays a role in neuronal differentiation using PC12 cells. During the process of nerve growth factor-induced neuronal differentiation of PC12 cells, PTBLP-L was down-regulated whereas PTBLP-S was up-regulated. Transfection of PTBLP-L into PC12 cells led to the suppression of neuronal differentiation. In PTBLP-S transfected cells, however, this suppression was not evident. When both PTBLP-L and PTBLP-S were co-transfected, the suppressive effect of PTBLP-L decreased. In differentiated cells, PTBLP-S localized in the nucleus and PTBLP-L was found dispersed throughout the cytoplasm and neuronal growth cone. These findings suggest that PTBLP-L acts as a negative regulator of neuronal differentiation and PTBLP-S acts as a competitor of PTBLP-L.

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