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Masanobu Suzuki

Publications and source records attributed to Masanobu Suzuki.

6 recordsLinked to original sources

Changes in the crystalline lens resulting from insertion of a phakic IOL (ICL) into the porcine eye.

BACKGROUND: Insertion of a phakic IOL offers these advantages: the corneal optical zone is not dissected or resected; preservation of the crystalline lens results in preservation of the accommodation force; and since the phakic IOL is removable, any error or change in refraction can be countered by exchanging it. However, the cause of secondary cataracts has never been clarified or discussed to date. METHODS: The following ICL lenses were inserted under general anaesthesia into 20 eyes of ten 3-month-old miniature pigs: a minus lens without holes into five eyes, a plus lens in two eyes, a minus lens with four holes around the lens haptics in three eyes, and a minus lens with a central hole in the optic in three eyes; and seven eyes were used as controls. The anterior segments were then photographed 1 week, 1 month and 3 months after surgery. At 3 months after surgery, Evans blue (EB) was infused into the vitreous under general anaesthesia, and after 30 min, the eyeball was enucleated, fixed and examined. RESULTS: In the case of the ICL without holes, the anterior subcapsular opacities were observed in all the eyes, and the anterior surfaces of the crystalline lenses were not stained with EB. Use of the ICL with four holes around the lens haptics resulted in light staining of the anterior surface of the crystalline lens, but the anterior subcapsular opacities observed were mild. As for the ICL with a hole in the centre of the optic, the anterior surface of the crystalline lens was stained and no anterior subcapsular opacities were observed. CONCLUSION: The results suggested that the insertion of an ICL brings about a change in the dynamics of the intraocular aqueous humour, reducing its circulation to the anterior surface of the crystalline lens. This is considered to cause a metabolic disturbance of the crystalline lens, resulting in anterior subcapsular opacification.

Animals↗

[Long-term clinical course of laser in situ keratomileusis--two year follow-up].

PURPOSE: To evaluate the cases that were treated with laser in situ keratomileusis (LASIK) and who were follwed up for a full 2-year period without fail. MATERIALS AND METHODS: LASIK was performed in 62 eyes of 35 patients between June 1997 and March 1999. Mean age was 29.1 years and the preoperative mean spherical equivalent refraction was -6.90 +/- 2.49 (mean +/- standard deviation) diopter (D). Five aspects were studied as follows. RESULTS: 1. SAFETY: 26 eyes (41.9%) gained 1 line or more in best corrected visual acuity. Twenty eyes (32.3%) were unchanged. Sixteen eyes(25.8%) lost 1 line. No eye lost 2 lines or more. The safety index was 1.04. 2. EFFICACY: The efficacy index was 0.85. 3. Predictability: Forty-eight eyes (77.4%) were predictable within +/- 0.5 D, and 55 eyes (88.7%) were within +/- 1.0 D. 4. Stability: Manifest refraction was relatively stable after 3 months. 5. Complication: No complications were experienced. CONCLUSIONS: Our 2-year follow-up showed that postoperatively LASIK was safe and effective.

Adolescent↗

Clinical outcomes of wavefront-guided laser in situ keratomileusis: 6-month follow-up.

PURPOSE: To evaluate the clinical outcomes 6 months after wavefront-guided laser in situ keratomileusis (LASIK) for myopia in Japan. SETTING: Department of Ophthalmology, Sanno Hospital, Tokyo, Japan. METHODS: This prospective study comprised 22 eyes of 12 patients treated with wavefront-guided LASIK who were available for evaluation at 6 months. The mean patient age was 31.2 years +/- 8.4 (SD) (range 23 to 50 years), and the mean preoperative spherical equivalent refraction was -7.30 +/- 2.72 diopters (D) (range -2.75 to -11.88 D). In all cases, preoperative wavefront analysis was performed with a Hartmann-Shack aberrometer and the Technolas 217z flying-spot excimer laser system (Bausch & Lomb) was used with 1.0 mm and 2.0 mm spot sizes and an active eye tracker with a 120 Hz tracking rate. The clinical outcomes of wavefront-guided LASIK were evaluated in terms of safety, efficacy, predictability, stability, complications, and preoperative and postoperative aberrations. RESULTS: At 6 months, 10 eyes had no change in best spectacle-correct visual acuity and 10 gained 1 or more lines. The safety index was 1.11 and the efficacy index, 0.82. Slight undercorrections were observed in highly myopic eyes. In all eyes, the postoperative refraction tended slightly toward myopia for 3 months and stabilized after that. No complication such as epithelial ingrowth, diffuse lamellar keratitis, or infection was observed. Comparison of the preoperative and postoperative aberrations showed that 2nd-order aberrations decreased and higher-order aberrations increased. In the 3rd order, aberrations increased in the high-myopia group (-6.0 D or worse) and decreased in the low to moderate-myopia group (better than -6.0 D). CONCLUSION: Wavefront-guided LASIK was a good option for refractive surgery, although a longer follow-up in a larger study is required.

Adult↗

[Long-term clinical course of excimer laser photorefractive keratectomy].

PURPOSE: Long-term clinical follow-up for 5 years or longer has not yet been reported in Japan. We performed excimer laser photorefractive keratectomy(PRK) on 181 eyes from 1990 to 1993, and 44 of those eyes could be followed for 8 to 10 years. METHODS: The 44 eyes were divided into 3 groups depending on degree of correction. We compared of safety, efficacy, predictability-spherical equivalent, stability, complication, and satisfaction among the 3 groups. RESULTS AND CONCLUSIONS: The first generation PRK was certified clinically to be safe and stable in patients corrected for low to moderate myopia.

Adult↗

[Late onset diffuse lamellar keratitis].

BACKGROUND: Diffuse lamellar keratitis (DLK) is marked by the presence of diffuse or multifocal infiltrates confined to the laser in situ keratomileusis(LASIK) interface. These infiltrates are culture-negative, and the etiology is thought to be noninfectious. Most cases of DLK occur within the first week or two following surgery. CASE: We describe two cases of diffuse lamellar keratitis that occurred 3 months after LASIK. These patients were treated with intensive topical corticosteroids. RESULTS: We treated the patients with topical corticosteroids, with rapid improvement in patient symptoms, visual acuity, and slit-lamp biomicroscopy. CONCLUSION: DLK may occur three months after LASIK.

Female↗

Late-onset diffuse lamellar keratitis.

BACKGROUND: Diffuse lamellar keratitis (DLK) is marked by the presence of diffuse or multifocal infiltrates confined to the laser in situ keratomileusis (LASIK) interface. These infiltrates are culture-negative, and the etiology is thought to be noninfectious. Most cases of DLK occur within the first week or 2 following surgery. CASES: We described 2 cases of DLK that occurred 3 months after LASIK. These patients were treated with intensive topical corticosteroids. RESULTS: Treatment with topical corticosteroid was instituted, with rapid improvement in patient symptoms, visual acuity, and slit-lamp biomicroscopic findings. CONCLUSION: DLK may occur as late as 3 months after LASIK.

Administration, Topical↗