[Visual outcomes of femto-LASIK after peneterating keratoplasty]

To determine the outcomes of visual correction with femto-LASIK following PK. In this prospective study, 34 eyes of 31 patient who had undergone thin - flap lasik due to high efractive error after corneal grafting were evaluated .After complete ocular examination and assessment of uncorrected and corrected distant visual acuity [UCVA and BCVA], the patients underwent femto-lasik using the Ziemer femto-LDV with 100 micron flap thickness. After 3 to 19 [10.14 +/- 4.81] months of follow-up, mean UCVA increased from 1.5 Log MAR preoperatively [5/100] to 0.3 LogMAR [5/10] postoperatively [P<0.05]. Mean BCVA also increased from 0.3 LogMAR [5/10] to 0.1 LogMAR [8/10] [P<0.05]. Mean spherical equivalent changed from -6.98 +/- 3.87 to -2.18 +/- 2.69 and mean of defocus equivalent also decreased from 10.32 +/- 3.74 preoperatively to 4.13 +/- 2.93 postoperatively [P<0.05 for both]. No significant intraoperative and postoperative complications occurred. Femto-LASIK surgery after penetrating keratoplasty is a successful procedure for correction of moderate to high refractive errors. It seems to be clinically safe, effective and predictable

Oscillatory photodynamic therapy for choroidal neovascularization and central serous retinopathy; a pilot study

To report the preliminary results of oscillatory photodynamic therapy [OPDT] for choroidal neovascularization [CNV] and central serous retinopathy [CSR]. This study included 7 eyes of 6 patients with CSR [2 eyes], idiopathic CNV [2 eyes], CNV due to age-related macular degeneration [AMD] [2 eyes], and peripapillary CNV secondary to presumed ocular histoplasmosis syndrome [1 eye]. Intravenous verteporfin [6 mg/m[2] body surface area] was infused over 10 minutes followed by oscillating laser [wavelength 689 nm] covering slightly beyond the entire lesion. An Area Centralis lens was applied and laser was delivered [600 mW/cm[2] fluence rate and 50 J/cm[2] dose]. Intravitreal bevacizumab and dexamethasone combination therapy was used with OPDT in 4 eyes with CNV; intravitreal dexamethasone and triamcinolone acetonide were injected in the other eye with CNV. Clinical examination, funduscopy, fluorescein angiography, and optical coherence tomography [OCT] were performed at baseline and after treatment. After mean follow-up of 7.1 +/- 5.1 months, visual acuity improved from 0.87 +/- 0.69 logMAR [20/160] to 0.60 +/- 0.65 logMAR [20/80] [P = 0.027]; central foveal thickness decreased from 322 +/- 62.1 to 240.7 +/- 34.8 microns as measured by OCT [P = 0.018]. Fluorescein angiography and OCT demonstrated cessation of vascular leakage, and resolution of hemorrhage and subretinal fluid in all eyes. No adverse events or recurrence were noted. OPDT was effective in treating CNV lesions and CSR. OPDT may be an improvement on standard PDT due to reduced side effects, thermal damage and scarring

[Histopathologic evaluation of optic neurotomy with MVR blade and excimer laser in cadaver eyes]

To evaluate the histopathologic features of optic neurotomy with microvitreoretinal [MVR] blade and excimer laser in cadaver eyes. Optic neurotomy was performed in 11 cadaver eyes using 20-gauge MVR blade and in three cadaver eyes with pulsed xenon chloride [XeCl] excimer laser [308 nm] via monofile lightconducting fiber with a core diameter of 200 microns. After tissue processing, hematoxylin and eosin stained slides were used to evaluate the posterior segment of the globes, including the optic nerve head. None of the cases in the MVR neurotomy group had scleral macro- or micro-perforation and no injury was induced to the central retinal vein or artery. In 10 cases, the distance between the neurotomy site and the central retinal vessels ranged from 50 to 500 micro at all histologic levels. In one remaining case this distance was approximately 10 micro on two histologic sections and about 200 micro at a third level. Intra-neural hemorrhage was found in 18% of cases. Neurotomy was successfully induced in two of three cases attempted with the excimer laser. In one case, due to cloudy media, it was not apparent whether the laser successfully induced the neurotomy and no neurotomy was evident on sectioning. MVR induced optic neurotomy is an effective procedure to create scleral outlet relaxation, without significant surgical complications such as scleral perforation or central retinal vascular injury. This preliminary study also demonstrates that the XeCl excimer laser can make nonmechanical cuts with relative ease and reliability

Ferrara intrastromal corneal ring segments in keratoconus

To evaluate the efficacy and safety of Ferrara intra-stromal corneal ring [FISCR] segments for keratoconus. The study was performed on 57 eyes of 44 patients with keratoconus and clear cornea who were contact lens intolerant. Subjects underwent complete ophthalmic examination before surgery. Objective and subjective refraction achieving the best visual acuity was used to determine the refractive error and Orbscan II corneal topography system provided the corneal data on pre- and post-operative visits. FISCR segments were implanted according to the manufacturers monograms and standard surgical method. Mean patients age was 26.7 +/- 6.8 years. Patients were followed for 2-14 months [mean, 9 months]. At last follow-up visit, mean +/- standard deviation improvement in main outcome measures were as follows: 5.4 +/- 3.65 D for spherical equivalent [P<0.001]. 1.89 +/- 2.25 D for magnitude of cylindrical error [P<0.001], 0.61 +/- 0.46 LogMAR for best corrected visual acuity [P<0.001], and 0.18 +/- 0.36 LogMAR for uncorrected visual acuity [P=0.002]. The rings were removed and reimplanted in 3 cases due to inadequate depth and in one case because of suspected infectious keratitis. Implantation of FISCR segments is a safe and reversible procedure, particularly in contact-lens-intolerant patients with keratoconus whose only option is corneal transplantation

[Effect of captopril on aqueous levels of angiotensin II in diabetic patients]

To determine whether angiotensin II levels in aqueous humor is related to diabetes mellitus and to evaluate the effect of captopril. In a case-control study, aqueous humor samples were obtained during cataract surgery from 58 eyes of 58 patients, of which 37 were diabetic. From these latter subjects, 16 had taken captopril [captopril group] and 21 had not taken nay angiotensin converting enzyme [ACE] inhibitor [non-captopril group]. Angiotensin level was assessed by radimmunoassay. Severity of macular edema was evaluated by clinical examination after surgery. Mann Whitey U test was used to assess the statistical difference of mean angiotensin II and Hb AIIC levels between the groups and Spearman's rank-order correlation coefficient was used to evaluate correlation between aqueous levels of angiotensin II and of macular edema. The aqueous levels of angiotensin II was significantly higher in diabetic patients [31.0 +/- 7.3 pg/ml] compared to non-diabetics [6.28 +/- 2.8 pg/ml]. [P<0.0001] Aqueous concentration of angiotensin II in the captopril group [16.3 +/- 6.5 ug/ml] was significantly lower than in the non-captopril group [75.73 +/- 9.36]. [P<0.0003] Severity of macular edema was significantly lower in the captopril group as compared to the non-captopril group such that 68.75% of the captopril groups vs 33.3% of the non-captopril group had macular edema [P<0.005]. These finding suggest that the aqueous level of angiotensin II is significantly correlated with the severity of macular edema and may have a role in pathogenesis of macular edema in diabetic patients. It seems that modulation of the rennin-angiotensin system may become a very important target for medical treatment in patients with diabetic macular edema

Effect of squalamine on iris neovascularization in monkeys

The purpose of this study was to investigate the effect of squalamine, an antiangiogenic aminosterol, in an experimental model of iris neovascularization. Iris neovascularization was created in cynomolgus monkeys by occluding retinal veins with an argon laser and inducing persistent hypotony with a central corneal suture. Twenty-four eyes were treated in three groups. In group 1, 4 eyes were injected intravitreally with 3 mug/0.1 ml squalamine and four eyes with balanced saline solution [controls] immediately after vein occlusion [day 1]; injections were repeated every three days for three weeks. In group 2, 1 mg/kg squalamine was administered with intravenous infusion in dextrose 5% in four animals; 4 control animals received only dextrose. Infusions began on day 1 and were repeated every 3 days for 3 weeks. In group 3, after the development of iris neovascularization on day 7, 1 mg/kg squalamine was injected systematically in 4 animals; 4 animals received dextrose 5%. Monkeys were examined by slit-lamp biomicroscopy and underwent color photography and fluorescein angiography. The study concluded that intravitreally injected squalamine did not affect the development of iris revascularization; however, systemic squalamine injection inhibited the development of iris revascularization and caused a partial regression of new vessels in a primate model

Trans-scleral and intravitreal contact ND: YAG laser application: an experimental study

A contact Nd: YAG laser with a sapphire tip [convex surface 2 mm in diameter] was used to coagulate the retina and ciliary body through the sclera. The laser energy was successfully transmitted through the sclera producing retinal coagulation and destruction of the ciliary body. A 0.2 mm in diameter sapphire tip and Nd YAG laser was used to perform transvitreal retinal coagulation, retinotomy and retinochoriodal incision. Minimal hemorrhage occurred when retinochoroidotomy was done. Probe-tissue adhesion occurred but could easily be separated. Contact application of laser energy is a modern developed technology used primarily with a sapphire tip for cutting tissue [Daikuzono et at, 1985]. Because laser incisions are commonly accompanied by coagulation, bleeding from the tissue is reduced to a minimum with this technique. The initial successful application of contact laser delivery have been reported independently by us [Peyman et al., 1987] and Ando and associates 1986. To our knowledge, no long term results of contact Nd: YAG laser on ocular tissues has been reported thus far

Ciliary body destruction and retinopexy using diode laser

Semiconductor lasers are recently finding increased application for the treatment of ophthalmic disorders. We used a diode laser with an output power 1 W through a fiberoptic light pipe [200 [micro]m diameter] to deliver laser energy through the scalera of pigmented rabbits. Ciliary body destruction occurred with energy levels of 300-400 mW and exposure time of 0.5 sec. Retinal photocoagulation was achieved with energy levels of 200-500 mW in 0.5 sec. Histologic examination of acute lesions demonstrated thermal destruction of ciliary body processes and retina. Chorioretinal scar formation was observed clinically and histologically within 2-3 weeks. Our data indicate that the transscleral diode laser may be used for destruction of the ciliary body processes or peripheral retinal coagulation in pigmented eyes

Internal pars plana sclerotomy with the contact ND: YAG laser: an experimental study

Transvitreal pars plana sclerotomy using the contact Nd: YAG laser with a sapphire probe was performed on a group of rabbit eyes and compared with a similar procedure performed with a Ziegler knife. Although the intraocular pressure [IOP] was lowered in both groups of animals, the reduction was greater and more lasting in the group on which the Nd: YAG laser with sapphire probe was used. This technique may have application in cases with extensive peripheral anterior synechiae or where a vitrectomy as a combination procedure to clear ocular media is performed