玻璃体切割术增加晶状体高氧中暴露:一种核性白内障形成的可能机制

Purpose: To report vitreous oxygen tension before, immediately after, and at longer times after vitrectomy. Design: A prospective, interventional consecutive case series. Methods: Oxygen was measured using an optical oxygen sensor in patients undergoing vitrectomy. Intraoperatively, oxygen measurements were taken before and after vitrectomy in two intraocular locations: adjacent to the lens and in the mid- vitreous. Results: Sixty- nine eyes underwent oxygen tension measurements at the time of vitrectomy. In baseline eyes, oxygen tension in the vitreous was low, measuring 8.7± 0.6 mm Hg adjacent to the lens and 7.1± 0.5 mm Hg in the mid- vitreous. The difference between the two locations was statistically significant (P< .003), indicating that vitreous gel maintains an intraocular oxygen gradient. Immediately after vitrectomy, oxygen tension in the fluid- filled eye was higher, measuring 69.6± 4.8 mm Hg adjacent to the lens and 75.6± 4.1 mm Hg in the mid- vitreous. There was no statistically significant oxygen gradient between the two locations. The difference in oxygen tension pre- and postvitrectomy is highly statistically signifi- cant (P < .0001 lens, P < .0001 mid- vitreous). In eyes with a history of vitrectomy and previous removal of the vitreous gel, the intraocular oxygen tension was significantly higher than in eyes with a formed vitreous gel undergoing a first vitrectomy (P< .02 lens, P< .003 mid- vitreous).Conclusion: Vitrectomy surgery significantly increases intraocular oxygen tension during and for prolonged periods after surgery. This exposes the crystalline lens to abnormally high oxygen and may lead to nuclear cataract formation.

0.5%莫西沙星眼液局部给药后在人房水和玻璃体中的渗透性药代动力学研究

Objective: To investigate the penetration of 0.5% moxifloxacin hydrochloride into the aqueous and vitreous after topical administration in humans. Methods: A prospective, nonrandomized study of 20 patients scheduled for vitrectomy surgery between September 1 and December 31, 2003. Aqueous and vitreous samples were obtained and analyzed after topical administration of 0.5% moxifloxacin hydrochloride, every 2 hours (q2h) or every 6 hours (q6h), for 3 days before surgery. Assays were performed using high-performance liquid chromatography. Results: Mean± SD moxifloxacin concentrations in the q2h group for the aqueous (n=9) and vitreous (n=10) were 2.28± 1.23 and 0.11± 0.05 μ g/mL, respectively. Mean± SD moxifloxacin concentrations in the q6h group for the aqueous (n=10) and vitreous (n=9) were 0.88± 0.88 and 0.06 ± 0.06 μ g/mL, respectively. The minimum inhibitory concentration for 90% of isolates (MIC90) was far exceeded in the aqueous for a wide spectrum of key pathogens, whereas it was not exceeded in the vitreous for several organisms. However, the minimum inhibitory concentration for 50% of the isolates was exceeded in the q2h vitreous group for Staphylococcus epidermidis, Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenzae, Bacillus cereus, and other gram-negative pathogens. Conclusions: The Endophthalmitis Vitrectomy Study revealed that 94.2% of isolates from postoperative endophthalmitis are gram-positive pathogens. Moxifloxacin has a spectrum of coverage that appropriately encompasses the most common organisms in endophthalmitis. The pharmacokinetic findings of this investigation show that relatively high aqueous levels can be achieved after topical administration. Further studies will help define the precise role of 0.5% moxifloxacin ophthalmic solution in the treatment of or prophylaxis against intraocular infections.

长期大剂量眼内激素应用的安全性

PURPOSE: To report the feasibility and safety profile of 2-mg and 6-mg fluoc inolone acetonide implants after longterm follow-up in eyes with choroidal neov ascularization (CNV)DESIGN: Prospective, noncomparative, interventional case ser ies of patients with non-age-related subfoveal choroidal neovascularization en rolled in a compassionate use protocol METHODS: Sustained drug delivery devices containing either 2 mg (eight eyes) or 6 mg (six eyes) of fluocinolone acetonide were implanted through the pars plana into the vitreous cavity of 14 patients w ith predominantly classic, subfoveal CNV. The main outcome measures were complic ations related to the device. Secondary outcome measures were involution of esta blished CNV, inhibition of recurrent CNV, and visual acuity RESULTS: Patients ha d a diagnosis of ocular histoplasmosis (seven), myopic degeneration (four), angi oid streaks (two), and punctate inner choroidopathy (one). Patients were followe d for an average of 33 months (range, 16 to 40 months). All 14 eyes developed el evated intraocular pressure and cataract. Four eyes developed nonischemic centra l retinal vein occlusion. Complications required implant removal in 8 eyes. Ten of 14 eyes demonstrated involution of CNV or inhibition of recurrent CNV. Ten ey es had stable or improved visual acuity. Median initial visual acuity was 20/64. Median final visual acuity was 20/40 CONCLUSIONS: Longterm follow-up demonstra tes a significant complication rate with the sustained release of high-dose int raocular corticosteroids. The complications are treatable, and eyes can retain g ood vision. This therapeutic approach warrants further study to identify if lowe r doses of corticosteroids may reduce the complication rate yet still be effecti ve in treating ocular disease.

口服莫西沙星后玻璃体和房水的渗透性研究

Objective: To investigate intraocular penetration of moxi-floxacin hydrochloride after oral administration. Methods: Prospective study of 15 patients scheduled for vitrectomy between September and November 2004 at the Barnes Retina Institute,St Louis,Mo. Aqueous,vitreous,and serum samples were analyzed from 15 patients after oral administration of 2 tablets containing 400 mg of moxifloxacin. Assays were performed using high-performanceliquid chromatography. Results: The mean± SD moxifloxacin concentrations in plasma (n=15),vitreous (n=13),and aqueous (n=13) samples were 3.56± 1.31 μ g/mL,1.34± 0.66 μ g/mL,and 1.58± 0.80 μ g/mL,respectively. Mean± SD sampling times after oral administration of the second moxifloxacin tablet for plasma,vitreous,and aqueous were 2.94± 0.81 hours,3.77± 0.92 hours,and 3.71± 0.89 hours,respectively. The percentages of plasma moxifloxacin concentration in the vitreous and aqueous were 37.6% and 44.3% ,respectively. Minimal inhibitory concentrations against 90% levels were exceeded against a wide spectrum of gram-positive and gram-negative pathogens in the vitreous and aqueous. Conclusions: Moxifloxacin has a spectrum of coverage that encompasses the most common organisms in endophthalmitis. The pharmacokinetic findings of this investigation reveal that orally administered moxifloxacin achieves therapeutic levels in the noninflamed eye. Because of their broad spectrum of coverage,low minimal inhibitory con centration against 90% levels,good tolerability,and excellent oral bioavailability,fourth-generation fluoroquinolones may represent a major advance for managing posterior segment infections.

玻璃体腔pegaptanib注射后发生视网膜色素上皮撕裂

PURPOSE:To report two cases of a retinal pigment epithelial tear after intravitreal injection of pegaptanib sodium.To our knowledge,this is the first report of this finding after intraocular antivascular endothelial growth factor therapy.DESIGN:Observational case reports.METHODS:Two patients presented with occult choroidal neovascularization and associated serous pigment epithelial detachment that was a result of agerelated macular degeneration.Both patients were treated with an intravitreal injection of pegaptanib sodium.RESULTS:One patient developed a retinal pigment epithelium tear one week after the intravitreal injection.The second patient developed a retinal pigment epithelium tear eight weeks after treatment.CONCLUSIONS:Although these cases may represent natural history,there should be a high index of suspicion for retinal pigment epithelium tears in patients who report significant visual deterioration after intravitreal injection of pegaptanib sodium.Further studies are needed to determine whether angiographic subtypes of choroidal neovascular membranes are more susceptible to developing retinal pigment epithelium tears after treatmentwith antivascular endothelial growth factor agents.

眶底骨折的碎骨引起眼内异物

PURPOSE: To describe the ophthalmoscopic and radiologic findings of a patient who sustained blunt orbital trauma. A piece of bone from the fractured orbital wall caused an intraocular foreign body. DESIGN: Case report. METHODS: An 18-yea r-old man underwent full ophthalmoscopic examination 1 week after sustaining bl unt ocular trauma to the right eye while playing basketball. B-scan ultrasonogr aphy and computed tomography of the orbits were also performed. RESULTS: Visual acuity, intraocular pressure, and anterior segment examination were normal. Fund uscopic examination revealed a fragment of bone that had penetrated the sclera, choroid, and retina. A hole in the sclera was visible. No treatment was performe d. Three months later, the patient had no ocular complaints or complications as a result of this injury. CONCLUSION: Bone from a patient’s orbit may cause an i ntraocular foreign body that may be followed conservatively in certain circumsta nces.

老年性性黄斑变性患者维替泊芬光动力疗法对近黄斑部脉络膜新生血管的治疗

To report the results of treating juxtafoveal choroidal neovascularization with photodynamic therapy using verteporfin in eyes with age-related macular degeneration. Seven patients with predominantly classic juxtafoveal choroidal neovascularization were treated by photodynamic therapy using verteporfin. Three of the 7 patients had a gain in visual acuity and 2 had a stabilization of vision. The remaining 2 patients had a decrease in visual acuity. Subfoveal extension of the choroidal neovascularization was not observed in any patient and all choroidal neovascularization lesions after treatment were found to be nonperfused on fluorescein angiography. The encouraging results based on this small pilot study suggest that photodynamic therapy should be considered for treatment of select juxtafoveal choroidal neovascularization due to age-related macular degeneration.