Biomedical subjects

Koji Esaki

Publications and source records attributed to Koji Esaki.

6 recordsLinked to original sources

PubMed2005

Changes in localization of amino acids in the detached cat retina.

PURPOSE: To investigate the distribution of amino acids (glutamate, aspartate, glutamine, GABA, glycine) in detached retinas with minimum postmortem artifact and to clarify the relation between amino acid distribution and histopathological change in the outer portion of detached retinas. METHODS: Unilateral retinal detachment was produced in cats by injecting 0.25% sodium hyaluronate into the subretinal space using a glass micropipet. The eyes were fixed by perfusion for 10 min, 1, 3, 6 and 24 h, 2, 3 and 7 days after detachment and then examined under conventional light- and electron-microscopic immunocytochemistry. RESULTS: For glutamate, aspartate and glutamine, the inner segments and perikarya of the photoreceptor cells, which were not immunopositive in the normal retinas, showed various degrees of immunoreactivity immediately after retinal detachment. Photoreceptor cells with the strong immunoreactivity developed necrosis. The staining pattern of GABA and glycine scarcely changed during the course of retinal detachment. CONCLUSIONS: Excess intracellular glutamate, aspartate and glutamine in photoreceptor cells may cause a part of neuronal death after retinal detachment.

Amino Acids↗

PubMed2005

New gonioscopy system using only infrared light.

PURPOSE: To describe an infrared gonioscopy system designed to observe the anterior chamber angle under natural mydriasis in a completely darkened room. METHODS: An infrared light filter was used to modify the light source of the slit-lamp microscope. A television monitor connected to a CCD monochrome camera was used to indirectly observe the angle. RESULTS: Use of the infrared system enabled observation of the angle under natural mydriasis in a completely darkened room. CONCLUSION: Infrared gonioscopy is a useful procedure for the observation of the angle under natural mydriasis.

Anterior Chamber↗

PubMed2004

Evaluation of eyes with relative pupillary block by indentation ultrasound biomicroscopy gonioscopy.

PURPOSE: To investigate changes in anterior chamber angle configuration with indentation ultrasound biomicroscopy gonioscopy of relative pupillary block (RPB). DESIGN: Cross-sectional study. METHODS: This study included 26 eyes of 26 patients with RPB. We determined angle opening distance 500 and angle recess area using indentation ultrasound biomicroscopy gonioscopy and compared a small-sized standard eye cup with a new eye cup with an area for inducing pressure. RESULTS: Indentation ultrasound biomicroscopy images documented concavity of the iris in eyes with RPB. Both the new and the small standard eye cups widened the anterior chamber angle significantly (P <.0001) without causing corneal damage. Angle changes were significantly greater for the new eye cup design. CONCLUSIONS: Indentation ultrasound biomicroscopy gonioscopy is a useful technique for observation and diagnosis of RPB. Using a small standard or the newly designed eye cup, the procedure can be performed easily and without causing corneal damage.

Aged↗

PubMed2004

Evaluation and comparison of indentation ultrasound biomicroscopy gonioscopy in relative pupillary block, peripheral anterior synechia, and plateau iris configuration.

PURPOSE: To evaluate and compare the findings and changes of the anterior chamber angle configuration with indentation ultrasound biomicroscopy (UBM) gonioscopy in relative pupillary block (RPB), peripheral anterior synechia (PAS), and plateau iris configuration (PIC). METHODS: This study included 73 eyes of 52 patients with RPB (n = 26), PAS (n = 21), or PIC (n = 26). First, a conventional UBM scan was performed using a normal size standard eye cup before indentation. Then, for indentation UBM gonioscopy, scans were performed using a new eye cup that we designed. For evaluation of the angle, angle opening distance 500 and angle recess area were recorded and evaluated with regard to the effect of expansion on the anterior chamber angle. RESULTS: Indentation UBM gonioscopy showed the characteristic images in each of the eyes. The angle of all examined eyes was significantly widened with indentation (P < 0.01). The angle changes in eyes with RPB were significantly greater than in eyes with PAS or PIC (P < 0.01). CONCLUSION: Indentation UBM gonioscopy is a very useful method for observing the angle and diagnosis of RPB, PAS, and PIC.

Aged↗

PubMedDate not supplied

Supraciliochoroidal fluid at an early stage after trabeculectomy.

PURPOSE: To detect the presence of supraciliochoroidal fluid (SCF) by ultrasound biomicroscopy (UBM) at an early stage after trabeculectomy. METHODS: Trabeculectomy with mitomycin C was performed on 14 patients (15 eyes) with medically uncontrolled glaucoma. The ciliary bodies were observed using UBM testing, which was conducted preoperatively and within 2 weeks after the procedure. RESULTS: SCF was detected postoperatively in 6 eyes. One eye also had choroidal detachment (CD), as seen with an indirect ophthalmoscope; and 5 eyes (33%) had SCF without intraocular inflammatory clinical signs, postoperative changes of the anterior chamber depth, or obvious CD. The SCF in 4 eyes disappeared within 4 weeks after the trabeculectomy. The intraocular pressure (IOP) was 6.4 +/- 3.4 mm Hg (mean +/- SD) when SCF was detected and it rose to 13.2 +/- 7.2 mm Hg when the SCF disappeared. The IOP was 11.4 +/- 4.0 mm Hg in the eyes without SCF, which was significantly higher than that seen in the eyes with SCF. CONCLUSIONS: At an early stage after trabeculectomy, SCF without subclinical CD was detected in some cases by UBM. Compared with the reported frequency of SCF after 3 or 6 months, our study revealed that SCF was present more frequently at an early stage after trabeculectomy. Our results may indicate that the presence of SCF is related to the early low IOP after trabeculectomy and that the disappearance of SCF induces the elevation of IOP.

Aged↗

PubMedDate not supplied

Extrusion and fragmentation of hydrogel exoplant 11 years after scleral buckling surgery.

MAI or MIRAgel is a hydrogel developed as a scleral buckling material. We identified upper lid masses and a limitation of supraduction in the left eye of a patient who was associated with extrusion and fragmentation of the MIRAgel episcleral exoplant 11 years after scleral buckling surgery. The material could not be removed completely because of fragmentation. Fragmentation and extrusion of MIRAgel may be rare, but periodic long-term follow-up examinations should be performed after this product has been used.

Aged↗