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Dive into the research topics where Kiyotaka Kitagawa is active.

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Featured researches published by Kiyotaka Kitagawa.


American Journal of Ophthalmology | 2003

Optic neuropathy produced by a compressed mucocele in an onodi cell

Kiyotaka Kitagawa; Seiji Hayasaka; Katsutoshi Shimizu; Yasunori Nagaki

PURPOSE To describe a patient with compressive optic neuropathy caused by a mucocele in an Onodi cell. DESIGN Interventional case report. METHODS A 73-year-old man complained of sudden visual loss in the left eye 10 days after cataract surgery. Coronal computed tomography showed a homogeneous mass in an Onodi cell. Magnetic resonance imaging revealed an oval-shaped lesion that compressed the left optic nerve. RESULTS After endoscopic microsurgery of the paranasal sinus, visual acuity in the left eye improved. Histopathological examination of the excised specimen showed a mucocele. CONCLUSIONS Ophthalmologists should be aware that the mucocele in the Onodi cell, an anatomical variation of the paranasal sinus, may compress the optic nerve.


American Journal of Ophthalmology | 2009

A Hyperdry Amniotic Membrane Patch Using a Tissue Adhesive for Corneal Perforations and Bleb Leaks

Kiyotaka Kitagawa; Shuichiro Yanagisawa; Kazuhiko Watanabe; Tatsuya Yunoki; Atsushi Hayashi; Motonori Okabe; Toshio Nikaido

PURPOSE To evaluate the efficacy of hyperdry amniotic membrane (AM) patching attached using a tissue adhesive for corneal perforations and glaucoma filtering bleb leaks. DESIGN Prospective, noncomparative, interventional case series. METHODS Five eyes of 5 patients (glaucoma bleb leaks, 2 eyes; corneal perforations, 3 eyes) were treated with a single-layer patch of dried AM using a biological tissue adhesive. The dried AM was prepared with consecutive far-infrared rays and microwaves (hyperdry method) and was sterilized by gamma-ray irradiation. The dried AM was cut to the desired size and shape, and the tissue adhesive was applied to the amniotic epithelial side of the dried membrane. After applying the tissue adhesive, the dried membrane with glue applied then was positioned to cover the conjunctival bleb leak site or corneal perforation lesion using forceps. A therapeutic hydrogel contact lens then was installed as a bandage. RESULTS Bleb leaks or corneal perforations were repaired successfully within 21 days in all 5 cases. There were no remarkable adverse effects, and there was no recurrence of bleb leak or corneal perforation. CONCLUSIONS The hyperdry AM is a useful substrate, and this surgical procedure is a promising method to treat glaucoma filtering bleb leak or corneal perforation, which may result in serious vision-threatening ocular complications.


Japanese Journal of Ophthalmology | 2011

Use of a hyperdried cross-linked amniotic membrane as initial therapy for corneal perforations

Kiyotaka Kitagawa; Motonori Okabe; Shuichiro Yanagisawa; Xue-Yun Zhang; Toshio Nikaido; Atsushi Hayashi

PurposeTo report the use of hyperdried cross-linked (HDCL) amniotic membrane (AM) patching with tissue adhesive as an initial therapy for corneal perforations.MethodsCryopreserved AM was cross-linked with 0.1% glutaraldehyde and then dried using far-infrared rays and microwaves (hyperdry method). Three eyes of three patients with corneal perforations of up to 3 mm in diameter were included in this study. They were treated with a single-layer patch of HDCL-AM applied with a tissue adhesive (2-octyl-cyanoacrylate). We also evaluated the resistance of HDCL-AM to collagenases during in vitro digestion testing.ResultsIn all three cases, the corneal perforations were repaired within 28 days (range, 17–28 days). No recurrence occurred during the follow-up period (3–6 months). In the collagenase digestion testing, the HDCL-AM did not dissolve until 48 h, whereas the cryopreserved AM completely dissolved within 60 min.ConclusionsThree cases of corneal perforations were successfully managed using HDCL-AM patching with tissue adhesive. The HDCL-AM was resistant to collagenases during in vitro digestion testing. The HDCL-AM was a useful substrate for corneal perforations. This simple surgical technique may be one of the initial therapeutic options for corneal perforations.


Prostaglandins & Other Lipid Mediators | 2001

Aqueous flare elevation induced by transcorneal application of highly selective agonists for prostaglandin E2 receptor subtypes in pigmented rabbits: Effect of tetramethylpyrazine

Kiyotaka Kitagawa; Seiji Hayasaka; Kazuhiko Watanabe; Yasunori Nagaki

We examined the disruptive effect of highly selective agonists for prostaglandin E2 receptor subtypes (EP1, EP2, EP3 and EP4) on the blood-aqueous barrier, and evaluated the inhibitory effect of tetramethylpyrazine, an active component of Ligusticum wallichii, on the elevation of aqueous flare induced by the EP agonists in pigmented rabbits. Highly selective EP agonists (ONO-DI-004, EP1 agonist; ONO-AE1-259-01, EP2 agonist; ONO-AE-248, EP3 agonist; ONO-AE1-329, EP4 agonist) at 12.5 to 250 microg/ml were transcorneally administered to the eyes of pigmented rabbits using a glass cylinder. Animals were pretreated intravenously with tetramethylpyrazine (10 or 30 mg/kg) 30 minutes before application of the EP2 or the EP4 agonist. Aqueous flare was measured using a laser flare-cell meter. Aqueous flare intensity was expressed as the area under the curve (AUC) in arbitrary units. After administration of ONO-AE1-259-01 or ONO-AE1-329, aqueous flare increased and then gradually decreased. ONO-DI-004 and ONO-AE-248 had almost no effect on aqueous flare elevation. The AUC of eyes in rabbits pretreated with tetramethylpyrazine, 10 or 30 mg/kg i.v., was significantly smaller than that of eyes in rabbits treated with ONO-AEI-259-01 alone. The AUC of eyes in rabbits pretreated with tetramethylpyrazine, 10 or 30 mg/kg i.v., was not significantly smaller than that of eyes in rabbits treated with ONO-AEI-329 only. The results indicated that EP2 and EP4 agonists induced aqueous flare elevation in pigmented rabbits, and that tetramethylpyrazine inhibited the aqueous flare elevation induced by the EP2 agonist but did not suppress the elevation induced by the EP4 agonist.


Journal of Biomedical Materials Research Part A | 2014

Hyperdry human amniotic membrane is useful material for tissue engineering: Physical, morphological properties, and safety as the new biological material

Motonori Okabe; Kiyotaka Kitagawa; Toshiko Yoshida; Takuma Suzuki; Hiroki Waki; Chika Koike; Etsuko Furuichi; Kiyoshi Katou; Yoshihiro Nomura; Yoshinori Uji; Atsushi Hayashi; Shigeru Saito; Toshio Nikaido

Human amniotic membrane (AM) has been used widely as graft biomaterial for a variety of clinical applications. But, there are some persistent problems related to the preparation, storage, and sterilization. To resolve these problems, we developed hyperdry AM (HD-AM) using far-infrared rays, depression of air, and microwaves and then sterilized by γ-ray irradiation. To elucidate the benefit of HD-AM as biological materials, compare with the physical and histological properties of HD-AM with a freeze-dried AM (FD-AM) as typical freeze-dried methods, evaluate the safety of HD-AM in vivo experiment used nude mice, and demonstrate the feasibility of HD-AM transplant in pterygium. The water permeability and the sieving coefficient of HD-AM were significantly lower than that of FD-AM. HD-AM has kept the morphological structure of epithelium and connective tissues. At 18 months after transplanted, single and multilayers of HD-AM in the intraperitoneal cavity was degraded without any infiltrated cells. For clinical treatment, recurrence of pterygium and regrowth of the subconjunctival fibrosis were not observed during the 6-month follow-up periods after the surgery. It was proposed that HD-AM was a safe and effective new biological material for clinical use including treatment for recurrent pterygium.


Case Reports in Ophthalmology | 2011

Short-term results of canaloplasty surgery for primary open-angle glaucoma in Japanese patients.

Kazuya Fujita; Kiyotaka Kitagawa; Yoshiki Ueta; Tomoko Nakamura; Akio Miyakoshi; Atsushi Hayashi

Purpose: To report surgical results of canaloplasty surgery for primary open-angle glaucoma (POAG) in Japanese patients. Methods: Eleven eyes of 9 POAG patients underwent canaloplasty surgery at Toyama University Hospital. Three eyes of 3 patients underwent canaloplasty alone and 8 eyes of 6 patients underwent canaloplasty combined with cataract surgery. Canaloplasty was performed with a 10-0 polypropylene tensioning suture and an iTrack™ 250A microcatheter. All patients were followed up for 12 months. Changes in intraocular pressure (IOP) and postoperative complications were examined. Results: Mean preoperative IOP was 23.4 ± 5.5 mm Hg. Mean number of antiglaucoma drops was 2.8 ± 0.6 before canaloplasty and decreased to 1.2 ± 0.8 at 12 months after canaloplasty (p < 0.01). Mean IOP decreased postoperatively, being 13.7 ± 2.8 mm Hg at 1 month, 12.8 ± 3.5 mm Hg at 3 months, 14.0 ± 4.4 mm Hg at 6 months, and 15.0 ± 4.1 mm Hg at 12 months. The most frequent postoperative complication was mild hyphema (45.5%), which disappeared within 14 days after surgery. Conclusions: Canaloplasty may be an alternative surgery for POAG patients to reduce IOP to a value of approximately 15 mm Hg.


Japanese Journal of Ophthalmology | 2001

Effects of Tetramethylpyrazine on Prostaglandin E2- and Prostaglandin E2 Receptor Agonist-induced Disruption of Blood-Aqueous Barrier in Pigmented Rabbits

Kiyotaka Kitagawa; Seiji Hayasaka; Yasunori Nagaki; Kazuhiko Watanabe

PURPOSE To evaluate the effect of tetramethylpyrazine on the elevation of aqueous flare and intraocular pressure (IOP) induced by prostaglandin (PG) E(2) and PGE(2) receptor (EP) agonists. METHODS PGE(2) or EP agonists (11-deoxy PGE(1), EP(2) agonist; 17-phenyl trinor PGE(2), EP(1) and EP(3) agonist; or sulprostone, EP(1) and EP(3) agonist), 25 microg/mL, were transcorneally administered to pigmented rabbits. Animals were pretreated with tetramethylpyrazine intravenously (10 or 30 mg/kg) or topically (0.1% solution). Aqueous flare was measured using a laser flare-cell meter, and the intensity was expressed as the area under the curve (AUC). Intraocular pressure was measured using a noncontact tonometer. RESULTS After administration of PGE(2), aqueous flare and IOP increased and then gradually decreased. The AUC of eyes pretreated with tetramethylpyrazine, 10 or 30 mg/kg, intravenously, or topical 0.1% solution, was significantly smaller than that of the controls. The mean Delta IOP of eyes pretreated with tetramethylpyrazine, 30 mg/kg intravenously, was significantly lower than that of the controls. After administration of 11-deoxy PGE(1), aqueous flare increased and then gradually decreased. 17-phenyl trinor PGE(2) and sulprostone did not disrupt the blood-aqueous barrier. The AUC of eyes pretreated with tetramethylpyrazine, 10 or 30 mg/kg, intravenously, before 11-deoxy PGE(1) application was significantly smaller than that of the controls. CONCLUSION The results indicated that tetramethylpyrazine inhibited PGE(2)- or 11-deoxy PGE(1)-induced elevation of aqueous flare and IOP.


Japanese Journal of Ophthalmology | 1998

Orbital lymphoma of mucosa-associated lymphoid tissue in a patient with rheumatoid arthritis

Yasunori Nagaki; Seiji Hayasaka; Kiyotaka Kitagawa; Yoshinobu Maeda

A 75-year-old male with rheumatoid arthritis complained of proptosis of the left eye. On examination, 6-mm left proptosis was seen. A hyperemic and swollen optic disc was visible in the left fundus. Laboratory test results showed positive rheumatoid factor. Computed tomography and magnetic resonance imaging showed a mass lesion in the left orbit. Histopathologic study of the excised specimen revealed centrocyte-like cells and lymphoplasmocytoid cells. Immunohistochemical study showed positive staining of CD 20 (B cells) and lambda light chain (immunoglobulin). The combination of rheumatoid arthritis and lymphoma of mucosa-associated lymphoid tissue in the orbit, as demonstrated in our patient, is rare.


Clinical Ophthalmology | 2013

Application of 2-octyl-cyanoacrylate for corneal perforation and glaucoma filtering bleb leak.

Motonori Okabe; Kiyotaka Kitagawa; Toshiko Yoshida; Chika Koike; Takeshi Katsumoto; Etsuko Fujihara; Toshio Nikaido

Background This paper reports on the efficacy of a tissue adhesive, 2-octyl-cyanoacrylate, in the treatment of corneal perforation and glaucoma filtering bleb leak. Methods Two eyes from two patients with corneal perforation or laceration and two eyes from two patients with bleb leak were included. The patients underwent application of 2-octyl-cyanoacrylate onto the perforated or leaking site, and a hydrogel contact lens was applied as a bandage. We also evaluated the in vitro cell toxicity of 2-octyl-cyanoacrylate in HeLa cells. Results The two cases of corneal perforation were repaired within 22 days with one application of the tissue adhesive. The two cases of bleb leak were repaired with 2–4 applications of the tissue adhesive over 134 (range 17–134) days). There were no recurrences or adverse effects during a mean follow-up period of 12.7 months. In vitro testing revealed that 2-octyl-cyanoacrylate was markedly toxic to HeLa cells. Conclusion Four patients with corneal perforation or bleb leak were successfully managed using 2-octyl-cyanoacrylate tissue adhesive. This simple and easy surgical technique may become an alternative therapeutic option for corneal perforation or bleb leak, although several applications of this tissue adhesive may be required. Although 2-octyl-cyanoacrylate was toxic to HeLa cells, no adverse clinical effects were noted using this adhesive.


Japanese Journal of Ophthalmology | 2003

Falsely elevated Intraocular pressure due to an abnormally thick cornea in a patient with nevus of Ota

Kiyotaka Kitagawa; Seiji Hayasaka; Yasunori Nagaki

BACKGROUND Several ocular complications, including glaucoma and ocular hypertension, have been reported in patients with nevus of Ota. CASE A 12-year-old boy with nevus of Ota on the left side of his face was referred for further examination of elevated intraocular pressure in his left eye. OBSERVATIONS Intraocular pressure measured with Goldmann tonometry was 19 mm Hg OD and 25 mm Hg OS. No visual field defects were detected by Goldmann or Humphrey perimetry. With ultrasonic pachymetry, the mean +/- SD of central corneal thickness was 560 +/- 4 microm in the right eye and 652 +/- 9 microm in the left. CONCLUSION Ophthalmologists should be aware that the abnormally thick cornea of patients with nevus of Ota may produce falsely elevated intraocular pressure readings.

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