results of photorefractive keratectomy with mitomycin-C in myopia correction after five years

Objective: To evaluate the results of photorefractive keratectomy [PRK] with mitomycin C in myopia correction after five years

Methods: This is a cross sectional study which included 145 eyes of 74 patients in 18 to 51 years age group that were undergoing Photorefractive keratectomy with mitomycin C using Allegretto Wave Eye-Q 400-Hz excimer laser platform in Markazi Eye Center, Tehran, Iran. All the surgical procedures were performed by the same surgeon. After five years follow-up evaluation including BCVA, UCVA, Refractive error measurement and external eye examination was performed

Results: The mean diopter of spherical equivalent before surgery was -3.40 +/- 1.73. The following findings were obtained after 5 years follow up visit: The mean spherical equivalent value: -0.08 +/- 0.40, the mean Log MARUCVA: 0.02 +/- 0.07, the mean Log MAR BCVA: 0.00 +/- 0.04

Conclusion: PRK is an effective, safe and predictable method used to correct myopia. The wave frontoptimized algorithm of the Allegretto Wave Eye-Q 400-Hz excimer laser platform demonstrated good refractive and visual results. Presence of variables such as gender, age and astigmatism before operation have no significant impact on the result of this operation

Anterior segment study with the Pentacam Scheimpflug camera in refractive surgery candidates

The purpose of this study was to evaluate the anterior segment measurements according to refractive status in a sample of the Iranian population. Rassoul Akram Hospital, Tehran University of Medical Sciences. In this study, refractive surgery candidates were assigned according to the refractive error to one of three groups: emmetropia, myopia, and hyperopia. Myopic eyes were further divided to four Subgroups: simple myopic group, simple myopic astigmatism group, high myopic group, and high myopia with astigmatism group. Anterior segment measurements with the Pentacam Scheimpflug system were performed in the right eye of all subjects. The study sample was comprised of 283 subjects with a mean age of 29.1 +/- 7.5 [standard deviation] years. Mean keratometry reading, Anterior chamber depth [ACD] and volume measurements were significantly higher in the myopic group and mean keratometry reading and anterior chamber angle measurements were significantly lower in the hyperopic group [P < 0.05, all comparisons]. Maximum anterior elevation [AE[max]] and maximum posterior elevation [PE[max]], Q value, progression index, minimum corneal thickness, and corneal volume measurements were similar for all groups [P > 0.05, all comparisons]. In the myopic subgroups, AE[max] and PE[max] and maximum keratometry [K[max]] were significantly higher, and ACD was lower in the astigmatic groups [P < 0.05, all comparisons]. The Q value was less negative in low myopia [P < 0.05]. Myopic eyes had steeper corneas than hyperopic eyes and anterior chamber measurements were significantly higher in the myopic eyes. In myopic eyes, AE[max] and PE[max] and K[max] measurements were higher, and ACD measurements were lower in the astigmatic groups

Vitrectomy for posterior segment intraocular foreign bodies, visual and anatomical outcomes

To evaluate the visual and anatomic results and determine the prognostic factors after pars plana vitrectomy and posterior segment intraocular foreign body [IOFB] removal. This retrospective study reviews the patients' charts of 48 consecutive patients with posterior segment IOFB who underwent pars plana vitrectomy and IOFB removal over a 4-year period, recently. Association between visual outcome and various preoperative, operative, and postoperative variables was statistically analyzed. Data were analyzed with the paired t-test and the chi square test. Statistical significance was indicated by P < 0.05. The mean interval between the time of injury and IOFB removal was 24 +/- 43.1 days and 27 [53%] eyes underwent IOFB removal within 7 days of the injury. Nine [19.1%] patients achieved a visual acuity of 20/40 or better. An improvement of visual acuity of at least three lines occurred in 21 [44.6%] eyes and the vision remained unchanged in 15 [31.9%] eyes. Postoperative retinal detachment occurred in five [10.6%] eyes. Visual improvement was more likely to occur in eyes with lower levels of presenting visual acuity [P = 0.2]. Visual improvement was not associated with an entry site and IOFB location, lens injury, time to surgery, and pre- and post-operative retinal detachment. At the end of follow up, anatomical success was achieved in 97.9% of eyes. High anatomical success could be achieved after the removal of posterior segment IOFBs by vitrectomy, despite a delay in surgery. Poor visual outcome may be mainly due to the initial ocular injury

Isolates and antibiotic resistance of culture-proven endophthalmitis cases presented to a referral center in Tehran

To evaluate the spectrum of organisms causing endophthalmitis and their resistance pattern to standard antimicrobial agents. Medical records of culture positive eyes treated at Rassoul Akram Hospital for endophthalmitis during the past 5 years were reviewed. Specimens were obtained during pars plana vitrectomy or vitreous tap. Sixty-five isolates including 36 [55.4%] gram-positive organisms, 28 gram-negative organisms [43.1%], and 1 [1.5%] fungus were studied. The most common organism identified was Coagulase-negative staphylococcus in 16 eyes [24.6%]. Among the antibiotics available for intravitreal injection, the least antibiotic resistance was for vancomycin in gram-positive organisms and amikacin and ceftazidime in gram-negative isolates. Gram-positive isolates were the most prevalent organisms; however, a high isolation rate for gram-negative organisms was obtained. Considering that no single antibiotic provides coverage for all of the organisms, a combination therapy using vancomycin/amikacin or vancomycin/ceftazidime seems to be useful as the initial empiric treatment of suspected bacterial endophthalmitis

Intravitreal bevacizumab for pseudophakic cystoid macular edema; a systematic review

Cystoid macular edema [CME] is a major cause of decreased vision after complicated or uncomplicated cataract surgery. This paper reviews the use of intravitreal bevacizumab [IVB] injection for treatment of pseudophakic CME. In a literature search of all articles available on Medline and Scopus databases, 11 studies including one prospective and 4 retrospective studies, 4 case reports, one letter to editor and one review article were identified. All articles except one, reported the use of IVB for chronic CME unresponsive to at least one conventional treatment modality. The level of evidence for all studies was categorized as low or very low. Although intravitreal bevacizumab might be effective for many cases of pseudophakic CME, its use should be reserved for eyes unresponsive to conventional treatment modalities.

Characteristics and surgical outcomes of rhegmatogenous retinal detachment following myopic LASIK

To describe the clinical features and surgical outcomes of rhegmatogenous retinal detachment [RRD] following myopic laser in situ keratomileusis [LASIK]. In a retrospective, non-comparative case series, 46 eyes that had undergone vitreoretinal surgery for management of RRD following myopic LASIK were identified. Data was reviewed with emphasis on characteristics of the RRD, employed surgical techniques, and anatomic and visual outcomes. Mean pre-LASIK myopia was -9.7 +/- 3.9 [range -4.00 to -18.00] diopters [D]. Mean interval between LASIK and development of RRD was 11.6 +/- 11.2 months. Posterior vitreous detachment was present in 44 eyes [95.6%]. The retinal breaks included flap tears in 36 [78.3%] eyes, giant tears in 8 [17.4%] eyes and atrophic holes in 2 [4.3%] eyes. In eyes with flap tears, the breaks were multiple, large or posterior to the equator in 24 [66.7%] eyes. Retinal breaks were related to lattice degeneration in 20 [43.5%] eyes of which, three had history of prophylactic barrier laser photocoagulation. Scleral buckling was performed as the initial procedure in 32 [69.6%] eyes and primary vitrectomy was undertaken in 14 [30.4%] eyes. The initial surgical procedure failed in 14 [30.4%] eyes due to proliferative vitreoretinopathy [PVR]. Retinal reattachment was finally achieved in 43 [93.4%] eyes. Postoperative visual acuity >/= 20/40 and >/= 20/200 was achieved in 16 [34.8%] and 25 [54.3%] eyes, respectively. Post-LASIK retinal detachment has a complex nature in eyes with moderate to high myopia. The retinal detachment is complex in terms of size, number and location of retinal breaks, is associated with a high rate of PVR and entails unfavorable visual outcomes

Two different doses of intravitreal bevacizumab for treatment of choroidal neovascularization associated with age-related macular degeneration

To compare the efficacy and safety of 1.25 mg versus 2.5 mg intravitreal bevacizumab [IVB] for treatment of choroidal neovascularization [CNV] associated with age-related macular degeneration [AMD]. In this randomized clinical trial, consecutive patients with active CNV associated with AMD received 1.25 mg or 2.5 mg IVB. Best corrected visual acuity [BCVA], foveal thickness and side effects of therapy were evaluated one and three months after intervention. Overall 86 subjects were enrolled and completed the scheduled follow-up. Forty seven and 39 patients received 1.25 and 2.5 mg IVB respectively. The study groups were balanced in terms of baseline characteristics such as age, BCVA and foveal thickness. Mean improvement in BCVA was 0.06 +/- 0.3 logMAR in the 1.25 mg group and 0.07 +/- 0.34 logMAR in the 2.5 mg group [P=0.9]. Mean decrease in foveal thickness was 49 +/- 36 micro m in the 1.25 mg group and 65 +/- 31micro m in the 2.5 mg group [P=0.6]. Three cases of vitreous reaction and one case of massive subretinal hemorrhage were observed in the 2.5 mg group. Double dose [2.5 mg] IVB does not seem to be more effective than regular dose [1.25 mg] injections for treatment of CNV due to AMD and may lead to more complications

Vitreopapillary traction in nonarteritic anterior ischemic optic neuropathy

To describe the association between vitreous traction on the optic disc and nonarteritic anterior ischemic optic neuropathy [NAION]. Eighty three eyes of 83 patients with NAION were evaluated by optical coherence tomography [OCT] for detecting vitreous adhesion to the optic nerve head with separation from the adjacent retina [partial posterior vitreous detachment]. Eyes which were negative for such adhesion underwent ultrasonography to detect complete posterior vitreous detachment [PVD]. Fifty male and 33 female subjects with mean age of 51.9 +/- 10 years were studied. Partial PVD with optic nerve head adhesion was found in 54 patients [65.1%] using OCT. Ultrasonography detected complete PVD in all other eyes with optically empty spaces on OCT. Vitreous traction on the optic nerve head from partial PVD may play a causative role in some cases of NAION. This traction may impair vascular supply and/or axoplasmic flow leading to signs and symptoms of NAION