مجله چشم پزشکی بینا
سال بیست و یکم شماره 1 (پاییز 1394)

To determine the effect of photorefractive keratectomy (PRK) on improvement of involuntary eye movements and visual functions in myopic patients with congenital nystagmus. This prospective interventional case series included patients with congenital nystagmus and myopia ≥ -1 D who underwent PRK over a 2-year period. Complete ophthalmological examinations including visual acuity, contrast sensitivity and video-nystagmography were performed and compared before and 3 months after PRK. A total of 24 eyes of 12 patients with a mean age of 23±2 years were enrolled in the study. Spherical equivalent was -2.82 ± 1.65 preoperatively and -0.26 ± 0.25 postoperatively (P<0.001). Pre- and postoperative mean sphere was -2.16±1.36 and -0.10±0.35 and astigmatism was -1.33 ± 1.14 and -0.31 ± 0.51, respectively (P<0.001 for both comparisons). Mono-ocular visual acuity was improved from 0.36±0.21 in LogMAR preoperatively to 0.27±0.25 LogMAR postoperatively (P<0.001). Binocular visual acuity was significantly improved from 0.33±0.2 LogMAR to 0.17±0.16 LogMAR (P<0.001). A significant increase in contrast sensitivity was observed in low (P<0.001), intermediate (P<0.001) and high (P=0.01) spatial frequencies. Frequency, amplitude and intensity of nystagmus were significantly decreased after PRK (p<0.001). There was no correlation between degree of myopic correction and improvement in sensory and motor indices of nystagmus (P>0.1 for all correlations). PRK in patients with congenital nystagmus increased mono-ocular and binocular vision. Additionally, contrast sensitivity and motor indices of nystagmus (frequency, amplitude and intensity) were significantly improved postoperatively.

To evaluate the effect of limited dissection of tenon sheath on the outcome of horizontal strabismus surgery. Patients with horizontal strabismus, aged between six and 50 years, were enrolled in this non-randomized study. Patients with pattern and vertical strabismus or a history of strabismus surgery were excluded. The strabismus surgeries consisted of bimedial recession (BMR), bilateral recession (BLR), and recession and resection (R&R) depending on the type of horizontal strabismus and presence of amblyopia. The participants were divided into the case and control group. The method of operation was similar in both groups except for the amount of Tenon sheath dissection. In the control group, the Tenon sheath was cut 10 millimeters behind the insertion of the muscle and all the intramuscular connections were cut as much as possible. In the case group, the Tenon capsule was cut 3-4 mm posterior to the location of the sutures over the recessed or resected muscles and intermuscular connections were left intact. Fifty-four patients were enrolled in the study with 27 patients in each study group. There was no statistical difference between the two groups in terms of demographic variables. In both groups, the angle of strabismus was significantly reduced (P<0.05) postoperatively irrespective of the type of surgery. There was no significant difference between the two groups in terms of the corrected strabismus angle. After BMR, the angle of correction was 2.6±0.4 prism diopters per millimeter of muscle recession in the case group and 2.2±0.9 prism diopters per millimeter in the control group. After BLR, the angle of strabismus was corrected by 2.3 ±0.2 prism diopters per millimeter of muscle recession in the case group and 2.2±0.2 prism diopters per millimeter in the control group. After R & R performed for esotropia, the angle of strabismus was corrected by 3.4 ±0.3 prism diopters per millimeter of muscle recession or resection in the case group and 3.2± 0.2 prism diopters per millimeter in the control group. After R & R for exotropia, the angle of strabismus correction was 3.1±0.5 prism diopters per millimeter of muscle recession or resection in the case group, and 2.7±0.3 prism diopters per millimeter in the control group. The extent of the Tenon dissection as well as cutting the intermuscular connections had no significant effect on the corrected strabismus angle. Therefore, it is advisable to preserve the Tenon capsule and intermuscular connections as much as possible to reduce postoperative complications.

To separate and characterize orbital fat-derived stem cells (OFSCs) and compare its cellular and molecular properties with those of bone marrow-derived mesenchymal stem cells (MSCs) and adipose-derived stem cells (ASCs). Stem cells from orbital fat, abdominal fat and bone marrow aspirates have been isolated. We assessed stem cell specific cell surface markers using cytometry, osteoblast and adipocyte differentiation potential using special stains, and cellular proliferation rate using MTT test and expression of pleuripotency genes by Real-Time polymerase chain reaction (PCR). We also assayed wound healing using a scratch test and expression of corneal epithelial specific cell markers using an air lifting test. Results of flow cytometry showed that OFSCs were positive for CD105, CD90, CD44, CD166 and CD73 and negative for CD34, CD45, CD31 and CD133, similar to MSCs and ASCs. Differentiation to osteoblast and adipocyte was observed in all groups. OFSCs healed more rapidly as compared to MSCs and ASCs. Only OFSCs expressed epithelial markers KRT3, KRT12 and Connexin43 after air lifting. Orbital fat-derived stem cells had a high capability of proliferation and differentiation. Given the possibility of expression of epithelial markers and the potential of regeneration as well as its close location to the eye, these cells can be considered for cell therapy to treat persistent corneal epithelial defects.

To evaluate the effect of intravitreal Bevacizumab (IVB) injection on sustained intraocular pressure (IOP) This non-randomized prospective study was conducted on 359 eyes of 359 patients in Amir Almomenin (Rasht) and Labbafinejad (Tehran) Hospitals. After history taking and complete ocular examination, IOP was measured one week and one day before injection (twice at each session), and 1, 7 and 30 days after injection (three times at each session). All IOP measurements were obtained by a single examiner. Of all eyes, 306 eyes (159 right and 147 left eyes) of 306 patients (42.2% men, 57.8% women) were eligible for the study. Indications included diabetic retinopathy (277 eyes; 90.5 %), retinal vein occlusion (20 eyes; 6.5%), neovascular age related macular degeneration (9 eyes; 2.9%). No sustained increase in IOP was observed in the injected and non-injected fellow eyes. No significant association was found between the IOP elevation and subject gender or indications for injection. IVB injection in eyes without a history of glaucoma did not lead to a sustained increase in IOP during one month after injection.

To assess parameters that had a capability of influencing the rate of big bubble formation during deep anterior lamellar keratoplasty (DALK) in keratoconus. A total of 290 consecutive eyes from 257 patients with keratoconus that underwent DALK using the big-bubble technique were enrolled. The influence of patient age and sex, family history of keratoconus, history of contact lens wear or vernal keratoconjunctivitis, the presence of Vogt’s striae or superficial opacities, keratometric readings, central and peripheral corneal thickness, anterior chamber depth, vitreous length, and trephination size on the rate of a bare DM achievement was investigated. DALK was performed in 289 of 290 eyes and a bare DM was successfully achieved in 229 (79.2%) eyes. The recipient sex and trephination size had a significant association with the success rate of big-bubble formation. The female sex decreased the odds of bare DM achievement by 0.44 times (P=0.02). For each 0.1-mm increase in the trephination size, the odds of the successful big-bubble formation increased by 1.36 times (P=0.03). Other factors failed to demonstrate any significant association with the rate of successful bare DM achievement. The rate of successful big-bubble formation was 79.2% in keratoconus. Among different factors, female sex predicted a less likelihood of big bubble formation while large trephination size was significantly associated with an increase in the chance of bare DM achievement.

The aim of this study was to compare higher-order aberrations between personalized treatment (PT) versus personalized treatment advanced (PTA) photorefractive keratectomy (PRK) for myopia and myopic astigmatism. In this clinical trial, 80 eyes of 40 patients who met inclusion criteria were enrolled. They underwent PRK using PT or PTA algorithm randomly. Higher-order aberrations were measured and compared between the study groups pre-operatively and at months 3 and 6 postoperatively. The two study groups were comparable in terms of preoperative higher-order aberrations. Compared to the preoperative values, higher-order aberrations were significantly increased in the PT group (p<0.001), but decreased in the PTA group (p<0.001). Spherical aberration exhibited a significant increase postoperatively in the PT group (p<0.001) but remained unchanged in the PTA group (P=0.57). PRK using PT algorithm resulted in an increase higher-order aberrations. PTA algorithm provided better results in terms of postoperative higher-order aberrations and could treat pre-existing higher-order aberrations.

To describe a new noninvasive method to assure correct orientation of donor lenticules in Descemet stripping automated endothelial keratoplasty (DSAEK) surgery. DSAEK surgery was performed in three eyes with the diagnosis of pseudophakic bullous keratopathy (PBK). For the laboratory part of the study, two whole globes and two precut corneoscleral buttons were used. The donor lenticules were inserted in correct orientation and upside down orientation in the eye-bank globes. When anterior chamber was completely filled with air, two or more shiny rings were formed at the borders of donor lenticules because of total internal reflection in the graft. In both live and eye-bank eyes, the smoother larger thinner outermost ring which represented endothelial side of the grafts was formed deeper and the smaller thicker innermost ring which represented stromal side was formed more superficial when the grafts were attached in correct orientation,. When the lenticules were inserted upside down in the eye-bank eyes, a reverse situation was observed and the largest ring formed more superficial. The double-ring sign can be used to assure the correct orientation of the donor lenticles at the end of the DSAEK surgery.

To investigate confocal scan features of corneal subbasal nerve plexus and epithelial dendritic cells in herpes simplex keratitis (HSK) as compared to Acanthamoeba keratitis (AK). Confocal scan records of patients with clinical and confocal microscopic features compatible with HSK and AK as well as confocal scan records of normal participants were reviewed. The density and morphologic parameters of epithelial dendritic cells (EDCs) and changes in subbasal nerve plexus (SNP) were evaluated and compared among the groups. A total of 52 eyes of 52 patients were enrolled: 12 eyes (23.08%) of 12 patient with clinical and confocal scan features of HSK, 20 eyes of 20 patients (38.46%) with clinical and confocal scan results compatible with AK, and 20 eyes (38.46%) of 20 normal subjects. Mean density, numbers, and area of EDCs were significantly increased in both HSK and AK groups compared to the controls (P<0.001). Main nerve trunk number, nerve branches, total nerve numbers, nerve diameter and subbasal nerve density were statistically lower in HSK and AK groups as compared to the controls (P<0.001). Nerve tortuosity was significantly decreased in HSK and AK groups in comparison to the normal eyes (P=0.013). No statistically significant difference was observed between the HSK and AK groups in abovementioned parameters. Using confocal scan, this study showed significant changes in mean density and morphometric parameters of SNP and EDCs in HSK and AK. The findings can indicate a strong interaction between immune response and corneal innervation in these two corneal diseases.

Tetracyclines are broad spectrum antibiotics which are inexpensive and widely available and have an appropriate safety profile. In addition to antibiotical effects, tetracyclines can inhibit matrix metaloproteinase and collagenase, and subsequently reduce inflammation, angiogenesis, and neovascularization. They have partial neuro-protective, anti-apoptotic and antioxidant properties. Given these properties, tetracyclines are commonly used for the management of some ocular diseases such as pdry eye, blepharitis, meibomian gland dysfunction, rosacea, chemical burn, vesicant injuries, graft rejection reactions, and pterygium. Sub-antibacterial doses (20-100 mg/day) are used for the aforementioned purposes. Recently some studies investigated the neuro-protective, anti-oxidant and anti-apoptotic properties of tetracyclines which can be exploited for some neuroretinal diseases including retinopathies and ischemia-reperfusion injuries. However, more studies are needed for these new applications of tetracyclines.

To report a case of severe macular edema following the taking of fingolimod in multiple sclerosis.Case Report: A 34-year-old woman with a long history of relapsing-remitting multiple sclerosis presented complaining of blurred vision in the left eye that started 1 week before the presentation. She had been taking fingolimod for 4 months. She was not diabetic and had no history of uveitis but reported an episode of retrobulbar optic neuritis in both eyes. The initial ophthalmic examination, which was performed 2 weeks before initiating fingolimod, revealed a best corrected visual acuity (BCVA) of 20/25 OU and no ocular abnormalities. Upon the recent presentation, BCVA was 20/25 OD and 20/70 OS and there was no afferent papillary defect. The examination of anterior segment and anterior vitreous was unremarkable. Retinal examination of the left eye revealed cystoid macular edema with no other inflammatory signs or vascular changes. The findings of spectral domain optical coherence tomography (SD-OCT) were compatible with macular edema and indicated that the central macular thickness (CMT) was 605 microns. Fingolimod was discontinued and sinarolac was started three times daily. After 6 weeks, BCVA was 20/25 OD and 20/30 OS. Macular edema was resolved clinically and SD-OCT exhibited a significant reduction in macular edema with a CMT of 277 microns. Fingolimod-associated macular edema is a benign complication of the drug used for multiple sclerosis and. This complication responds well to the drug discontinuation and topical non-steroidal anti-inflammatory administration.

To present a case of bilateral enlargement of eyelids in 29 year old man with sclromyxedema syndrome.Case Report: A 29- year- old man was referred to labbafinegad clinic with bilateral enlargment of upper and lower eyelids, and foreign body sensation since 9 year ago. Investigating of patients history show renal deasese(hematuria) since 9 year ago. In systemic examination the patients showed hands and feet involvement obviously. At further investhgations sclermyxderma was confirmed. Scleromyxedema is a rare, chronic and persistent idiopathic disorder characterized by a generalized papular eruption due to dermal mucin deposition with an increase in dermal collagen. Uusually associated with a systemic involvement and paraproteinemia. The disease is characterized with mucin deposits in the skin and/or other organs. Its etiology remains unknown affecting both genders equally between 30 and 50 years. The therapeutic options include numerous treatment modalities; however, no standard treatment exists as the rarity of this disease prevents the execution of controlled therapeutic trials.