臺灣博碩士論文加值系統

在確切的病兆點提供高濃度的抗生素投藥是感染性疾病的治療原則。目前對感染性眼內炎的治療是以重複眼內注射廣效性的抗生素為主，但是重複的眼球內注射會增加眼內感染，眼內出血及視網膜剝離的危險。因此，本篇論文主旨在探討使用生物可降解鞏膜釘投予眼內高濃度之抗生素來替代傳統注射治療的可行性。
鞏膜釘的製作是先將高分子共聚合物與抗生素及類固醇充分混合，再經過壓縮燒結。於動物體內實驗，鞏膜釘被證實能釋放高濃度且持續的抗生素與類固醇。此外，沒有顯著的眼球併發症諸如感染性眼內炎，視網膜剝離或鞏膜切開處滲漏。鞏膜切開傷口於鞏膜釘完全吸收後可自行癒合恢復。本實驗的結論是合併抗生素與類固醇的生物可降解鞏膜釘在治療眼內感染是可行的替代方式。

Delivering effective drugs at sufficiently high concentrations to the area of infection is a standard treatment for infectious disease, such as endophthalmitis. This is currently done by empirical trans pars plana intravitreal injection of both antibiotics directed against gram-positive and gram-negative microorganisms and steroids. However, injections by needles repeatedly may increase the risks of intraocular infection and hemorrhage as well as retinal detachment. This paper explores the alternative of using biodegradable polymers as scleral plugs for a long-term drug release in vivo. To manufacture plugs, poly(lactide-glycolide) copolymers were first mixed with vancomycin, amikacin and dexamethasone. The mixture was compressed and sintered at 55oC to form scleral plugs 1.4mm in diameter. Biodegradable scleral plugs released high concentrations of antibiotics (well above the minimum inhibitory concentrations, MIC) and steroids in vivo for the period of time needed to treat intraocular infection. In addition, no major complications such as infectious or sterile endophthalmitis, retinal detachment, ocular phthisis or uvea protrusion at sclerotomy site were observed throughout the experiment. The sclerotomy wound healed after total degradation of the scleral implants without leakage or local necrosis. Antibiotic/steroid-impregnated biodegradable scleral plugs may have a potential role in the treatment of various intraocular infections.

Table of Contents

CHAPTER 1 Introduction………………………………………… 1
CHAPTER 2 Materials and Methods…………………………….. 3
2.1 Materials…………..………….……………………… … 3
2.2 Preparation of compact scleral plugs……………….. 3
2.3 In vitro elution…………………………………… …… 4
2.4 Device implantation and in vivo concentrations.. 5
2.5 Biocompatibility of scleral implant ………………… 6
CHAPTER 3 Results………………….…………………… ……. 7
3.1 In vitro pharmacokinetics……….………………………… 7
3.2 In vivo pharmacokinetics………………………………….. 7
3.3 Clinical examinations………………………………… …… 8
3.4 Histopathologic analysis………………………… ……… 9
CHAPTER 4 Discussion………………….………………… …. 11
CHAPTER 5 Conclusions………………………………… ……. 15
REFERENCES……………………………………………. …… 23

Table of Figures

Figure 1 Scleral plugs …………………………………………. 16
Figure 2 In vitro release curve ……………………………. 17
Figure 3 In vivo release curve ……………………………. 18
Figure 4 Biocompatibility ……………………………………. 19
Figure 5 Clinical examination…………………………………. 20
Figure 6 Retina pathology ………………………………………. 21
Figure 7 Healing of sclerotomy…………………………………. 22

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