BINA
Year:2004 | Volume:10 | Issue:1 |Papers Count:19

Purpose: To evaluate the prevalence of contat lens wear among highschool girls and their general knowledge about contact lenses and also to evaluate the specific knowledge of contact lens wearers about the lens.Methods: In a cross-sectional study, 1664 students of22 randomly selected girl highschools were enrolled. A questionnaire including questions about wearing contact lens, age of first use, cause of lens wear, type of lens, source of providing, way of wearing, and medical and hygienic care was filled out by the participants. Contact lens wearers were classified in two groups according to the main cause of lens wear: cosmetic and therapeutic.Results: The prevalence of contact lens wear was 16.5% including 81.8% for cosmetic purposes and 18.2% for therapeutic reasons. The age of starting lens wear was before 14 in 36%. About 50% of contact lens wearers had at least once worn the lens of another person. General knowledge was often weak or little and the knowledge about serious complications of contact lens wear was good only in 43% of the students. There were no significant differences between weares and nonwearers regarding these issues. The source of providing of lens among the therapeutic group was physicians in 90% and boutiques in 2% corresponding figures were 9.8% and 32% respectively in the cosmetic group.The most common type of lens was soft (98%) and colored (84.3%). Lens handling was bad or inappropriate in 73.1%; however appropriate handling was greater in the therapeutic group (42%) than the cosmetic group (23.6%). Medical care was appropriate in 30.9% (68% in the therapeutic group and 22.7% in the cosmetic group). Hygienic care of lens was appropriate in 53.8% (62% in the therapeutic group and 52% in the cosmetic group). Hygienic care of lens container was appropriate in 16.4% (24% in the therapeutic group vs 4.7% in the cosmetic group). Specific knowledge of lens wearers was appropriate in 46.6% (58% in the therapeutic group vs 44% in the cosmetic group).Conclusion: The prevalence of contact lens wear among highschool girls in Tehran is considerable especially for cosmetic purposes. Furthermore, general and specific knowledge about contact lens use was inadequate in the majority of lens wearers.

Purpose: To evaluate the predictability, efficacy, and safety of iris-claw ArtisanTM phakic intraocular lenses for myopia.Methods: Through a prospective clinical study, 35 eyes of 21 patients with myopia from -5 to 26.5 diopters underwent implantation of the Artisan lens. Patients were examined 1, 3, and 7 days (all eyes); 1 month (28 eyes), 3 months (29 eyes), and 6 months (32 eyes) after the procedure. A thorough ophthalmic examination including endothelial cell count, pachymetry, and topography was performed before and after the operation.Results: Mean age of the patients was 31.6 years (range, 18-43). Mean spherical equivalent (SE) changed from -15.71±4.90 diopters (D) before surgery to -0.65±0.94 D at 1 month, -0.58±1.10 D at 3 months, and -0.56±0.89 D 6 months after surgery. At 6 months, 15 eyes (46.9%) had uncorrected visual acuity of 20/40 or better and 23 eyes (71.9%) had SE within±1.00 D of emmetropia. Two eyes lost 1 line and two eyes lost 2 lines of best-corrected visual acuity (BCV A), no eye lost more than 3 lines. Twenty-one eyes (65.6%) gained one to three lines of BCV A. Mean endothelial cell count changed from 2889 at baseline to 2823 at three months (P= 0.002). There was no significant change in corneal pachymetry. Sterile endophthalmitis was seen in 4 eyes 1.5 months postoperatively which were treated successfully by corticosteroid therapy. No angle closure glaucoma or ocular hypertension was seen at postoperative visits.Conclusion: Implantation of Artisan phakic lens was found to be predictable and efficient for correction of myopia. Its effect on corneal endothelium should be considered and more investigations are recommended.

Purpose: To evaluate the role of prophylactic topical steroids in the prevention of DLK after LASIK.Methods: In a randomized double blind clinical trial, 101 LASIK candidates aged 18 to 55 years were enrolled. Myopia ranged from -2 to -12 diopters and was stable for at least one year. No patient had any ocular or systemic contraindication for LASIK. From one day before surgery, topical betamethasone 0.1% was randomly applied for one eye every 4 hours while the other eye received placebo. One hour before surgery the dosage was increased to every 5 minutes for at least six times.All operations were performed by one surgeon (F.K). Both eyes were operated in one setting. Six hours after surgery, all the eyes were put on topical betamethasone every 2 hours and dosage was tapered depending on the response and according to the grade of DLK if present. Severity of DLK was graded according to the Linebarger-Lindstorm classification. Patients were regularly examined in the first week and if the postoperative course was uneventful they were re-examined one and three months after surgery. Vision (BCVA), refraction (cyclorefraction), and severity of DLK were documented by a third examiner at each visit.Results: One hundred eyes were in the treatment and 98 eyes were in the control group. In both groups, pre and post LASIK refraction and VA were comparable (P>0.05). There were no significant complications in both groups during or after LASIK except for DLK. DLK was seen in 55 eyes (55%) of the treatment group including 44 eyes (44%) with grade I and 11 eyes (11%) with grade II. In the control group DLK was seen in 36 eyes (36.7%) of which 29 eyes (29.5%) were grade I, and 7 eyes (7.2%) were grade II. There was no statistically significant difference between the incidence of DLK in the two groups (P= 0.81). More severe grades of DLK (III and IV) were not seen in any group.Conclusion: Although steroids (topical and systemic) playa key role in the treatment ofDLK, they seem to have no inhibitory role on DLK.

Purpose: To evaluate corneal thickness changes after soft contact lens (SCL) removal in LASIK candidates.Methods: Fifty LASIK candidates (100 eyes) with history of daily wear SCL for at least 6 months were enrolled in this descriptive study. Central corneal thickness was measured by ultrasonic pachymetry immediately after lens removal and then repeated daily at the same time, until the thickness became stable.Results: Subjects were aged between 18 to 40 years (mean, 28.5 years). Central corneal thickness immediately after lens removal was 557.4±32 µm and reached 521.8±25µm when corneal edema completely resolved. After discontinuation of SCL wear, corneal edema required 2- 15 days to resolve. Corneal thickness stabilized in 74% within the 1st week, in 24% during the 2nd week, and in 2% during the 3rd week. Older patients and more severe primary corneal edema needed longer time to recover. There was no significant correlation between sex and rate of corneal deswelling.Conclusion: It is important to discontinue SCL wear at least 15 days before refractive surgery for corneal thickness stabilization to achieve an accurate pachymetry.

Purpose: To compare the refractive results of penetrating keratoplasty (PK) in two groups of patients with keratoconus undergoing corneal grafting with different amounts of donor-recipient disparity (0.25 and 0.5 mm).Methods: As a randomized clinical trial and after performing a complete ocular examination and vitreous length measurement,30 patients with keratoconus were randomly assigned in two groups:15 patients underwent PK with 0.25 mm. graft-recipient disparity and the other 15 patients underwent the operation with 0.5 mm disparity. One surgeon performed all the operations using a single running suture technique. Best correctedvisual acuity and retractive errors were evaluated 1 year after PK and also two months after suture removal.Results: One year after PK and also 2 months after suture removal there was no statistically significant difference in BCVA between the two groups. Mean spherical and mean spherical equivalent refractive error was better in the 0.25 mm group, however this difference was not statistically significant (P>0.05). In vitreous length range of 16.2-17.7 mm (20 patients) mean spherical equivalent refractive error was -1.6 and -3.6 D in the 0.25 mm and 0.50 mm disparity groups, respectively (P= 0.03). Mean spherical error was also better in the 0.25 mm group as compared with the 0.5mmgroup (-0.8 versus -2.6 D, P= 0.05). Mean astigmaticr efractive error was minimally different between the two groups.Conclusion: Less donor-recipient disparity (0.25mmVs 0.50mm) seems to lead to better refractive outcomes in penetrating keratoplasty for eyes with keratoconus and vitreous length of 16.2-17.7 mm.

Purpose: To evaluate the diagnosis of intraocular tuberculosis (TB) with polymerase chain reaction (PCR) and to report 13 cases of presumed intraocular TB.Methods: Of 168 patients with uveitis, 13 patients (7.74%) had criteria for intraocular TB (TB group). Thirteen patients with non-TB uveitis were randomly selected as the control group. Samples for PCR were obtained from the aqueous humor. Systemic evaluations, tuberculin skin test, and aqueous PCR were performed in all patients. The clinical and paraclinical findings and the treatment of patients with presumed intraocular TB were evaluated.Results: Mean age of the TB group was 42.6±14y,9 patients were female and 4 were male. Mean age of the control group was 37.15±15.32,7 patients were male and 6 were female. Tuberculin skin test was positive in 11 patients of the TB group vs 2 patients in the control group (P=0.001). Three patients in the TB group (23%) and none of the control group had positive PCR test. Posterior segment findings in the TB group included multifocal choroiditis in 4 patients (30.77%), single choroidal nodule (tuberculoma) in 1, retinal perivasculitis in 1, macular edema in 1, and intermediate uveitis in 1. In 5 other patients, no findings were observed in the posterior segment. Coexistant lung or other organ disease was found only in one patient and positive family history for TB was found in another.Conclusion: Use of the Tuberculin skin test is advisable and if results are above 19 mm of induration, the possibility of intraocular TB is reinforced, but negative tests are not sufficient for exclusion. PCR-positive patients must be treated with complete anti-TB treatment for eradication of bacilli.

Purpose: To compare the prevalence of glaucoma among peptic ulcer patients with or without helicobacter pylori infection.Methods: Among 352 patients with an indication of gasterointestinal endoscopy for peptic problems, 120 patients in 18-88 years of age were included for evaluation of glaucoma. According to the results of histopathologic and urease test, they were divided into two groups: Helicobacter pylori positive and negative. All cases were evaluated by expert ophthalmologists for presence or absence of glaucoma in a double blind fashion. These patients were examined for lOP, visual field, and fundoscopic evidence of glaucoma.Results: Glaucoma was detected in 43.1 % of patients with positive histopathology for helicobacter pylori vs 22.5% in patients with negative histopathology for helicobacter pylori (P= 0.016). All cases of glaucoma were normal tension glaucoma.Conclusion: Prevalence of normal tension glaucoma in peptic ulcer patients with positive histopathology for helicobacter pylori is significantly more than patients with negative histopathology for helicobacter pylori. Ophthalmologic evaluation of these patients for early onset of glaucoma is suggested.

Purpose: To evaluate the effects of posterior subtenon triamcinolone acetonide (TA) injection on clinical, angiographic, and optical coherence tomographic (OCT) features in refractory diabetic macular edema (DME).Method: In a randomized double-masked placebo-controlled clinical trial, 38 consecutive patients (64 eyes) with DME refractory to previous laser therapy or not suitable for such treatment were studied. An equal number of eyes (32) were allocated in the treatment and control groups. Posterior subtenon injection of 40 mg TA in the treatment group and subconjnctival injection of 0.1 ml of lidocaine 2% in the control group was performed and repeated after two months. Clinical, angiographic, and OCT features were evaluated before intervention and after 4 months. Quantitative measurement of hard exudates (HE), size of foveal avascular zone (FAZ), and leakage was done using Photoshop 7-0 software.Results: Before injection, best corrected visual acuity (BCYA) was 0.93±0.39 LogMAR in the control group and 0.75±0.38 LogMAR in the treatment group (P= 0.078). At the last follow up, BCYA was 0.88±0.48 LogMAR in the control group and 0.71±0.42 LogMAR in the treatment group (P= 0.136). Before injection, central macular thickness (CMT) was 388.2±119.1 μm in controls and 392.2±153.6 μm in cases (P= 0.9). At the end of the study, CMT was 375.4±154.66 μm and 377.37±180.04 μlm in cases and controls, respectively (P=0.5). There was also no significant difference in HE, FAZ, and leakage changes in the angiograms. In 2 eyes of the treatment group, intraocular pressure exceeded 20 mmHg which was controlled by medication.Conclusion: Posterior subtenon injection of TA in the eyes with severe DME seems to have no effect on visual acuity and macular thickness.

Purpose: To compare the anatomical results of scleral buckling with or without retinopexy and to assess the effect of retinopexy on outcomes of the operation.Methods: This interventional case series was performed on 22 patients undergoing scleral buckling (segmental or encircling) with or without subretinal fluid drainage and without any type of retinopexy and 33 patients who received trans scleral retinal cryopexy around retinal break(s) in addition to above procedure. The two groups were matched regarding age, sex, myopia, aphakia, and number, size, and location of the break(s) and also stage of proliferative vitreoretinopathy (PVR).Results: In the non-retinopexy group, 19 patients (86.4%) had complete and 1 patient had partial retinal attachment after 10-24 months of follow up. The cause of failure in two cases was missed breaks out of the buckle area in one and PVR in the other patient. Overall success rate was 90.9% (20 of22) in this group. In the retinal cryopexy group, 26 patients (78.9%) had complete and 2 had partial attachment after 11-32 months of follow up. Attachment was not achieved in 3 patients and 2 patients developed redetachment 1 and 3 months later because of PVR. Overall success rate was 84.8% (28 of 33). The anatomical results in this two groups were comparable statistically (P=0.9).Conclusion: With permanent scleral buckling technique, retinal cryopexy does not seem to increase success rate defined as short term anatomical retinal reattachment.

Purpose: To evaluate the significance of the presence of pigment granules in the anterior vitreous as a reliable indicator of retinal breaks in patients with acute symptomatic posterior vitreous detachment (PVD).Methods: This cross sectional study included 209 phakic patients with acute symptomatic PVD.The patients underwent anterior vitreous examination and fundoscopy. Patients with diabetic retinopathy, intraocular hemorrhage, intraoacular inflammation, previous ocular surgery, and ocular trauma were not included. The role of age, sex, floaters or flashing, presence of pigment in the vitreous and retinal break were assessed.Result: The study was performed on 209 patients including 85 males and 124 females. Mean age was 59.18 years (range, 33-72 years). Thirty patients (14.3%) were found to have an associated retinal break, 27 of which also had pigment in the vitreous (90%). PVD symptoms were floaters in 44%, floaters & flashing in 41.2%, and flashing in 14.8%. Symptoms in patients who had retinal breaks were floaters in 60%, floaters & flashing in 36.7%, and flashing in 3.3%.Conclusion: Presence of pigment granules in the vitreous is a reliable indicator of retinal breaks in association with an acute PVD. Floaters were the most common presenting symptom in patients with retinal breaks.

Purpose: To compare the rate of fibrovascular ingrowth between primary and secondary orbital implants at varying time intervals after implantation.Methods: We prospectively compared the rate of fibrovascular ingrowth between primary and secondary implants by MRI and scinitigraphy in patients who underwent orbital implant surgery, 6 months after the operation.Results: Overall 103 patients underwent hydroxyapatite (HA) implantation including 75 cases of primary and 28 cases of secondary implants. Of 75 patients with primary implants, vascularization was seen in 13 (18%) by 1 month, 33 (45%) by 2 months, 58 (78%) by 3 months, and 70 (94%) patients by 6 months. However in 5 (6%) patients no vascularization was documented by MRI after 6 months. Of 26 cases of secondary implants, central vascularization was seen in 2 (7%) by 1 month, in 8 (29%) by 2 months, in 19 (68%) by 3 months, and in 23 (82%) by 6 months. However, in 5 (18%) cases no vascularization was seen after 6 months.Conclusion: This study demonstrated consistent central vascularization of hydroxyapatite orbital implants by MRI in the majority of cases after 6 months equally in primary and secondary implants.

Central retinal vein occlusion (CRVO) occurs at the scleral outlet where the optic nerve, central retinal artery, and central retinal vein enter the eye; therefore it may be considered a "compartment syndrome" which is defined as a neurovascular compression within this confined space of scleral outlet resulting in tissue ischemia and dysfunction. Transvitreal optic neurotomy (TON) is a new surgical technique advocated for treatment of CRVO. By this procedure and providing surgical relaxation of the scleral outlet, clearing of macular edema and interaretinal hemorrhage and improved retinal blood flow may reestablish. TON may be a beneficial surgical procedure for patients with severs CRVO, via decompressing the scleral outlet and by that affecting the optic nerve and the blood supply. In addition to scleral ring relaxation, other postulated mechanisms of effect in TON include development of opticociliary vessels and increased perfusion into pre-existing opticociliary vessels. Preliminary results of TON for CRVO have demonstrated encouraging results; however these results need to be reconfirmed in a randomized clinical trial.

Corneal transplantation is the most common and successful form of solid organ transplantation with a 2-year survival rate of over 90% in low risk cases. This high success rate may be due to the immune privileged status of the cornea, ACAID (anterior chamber associated immune deviation) induction phenomena and secretion of inhibitory molecules by corneal cells such as IL1-ra, IL-I a and Fas ligand. However, immunological rejection is the leading cause of corneal graft failure. This process is primarily mediated by CD4+ T cells of the Th1 phenotype. The mainstay of corneal graft rejection treatment is topical and systemic steroid. Recently topical and systemic cyclosporine A has also yielded promising results. This article reviews the molecular mechanisms of immunity in corneal graft rejection in addition to its prevention and treatment. Correct preoperative case selection is vital in preventing graft rejection.

Purpose: To present a case of acute myopia secondary to usage of Topiramate. Patient and findings: A 26-year-old female presented with 6-diopter myopia after two weeks of using topiramate for migraine headache. She improved after 3 days of cessation of this medicine. Conclusion: When a patient present with acute onset visual loss secondary to refractive error, history of drug usage can help for diagnosis.

Purpose: To report concomitant angioid streaks and skin lesions in a patient with β thalassemia. Patient and Findings: A 47-year-old female, a known case of β thalassemia, presented with gradual decrease of vision in her right eye. On indirect ophthalmoscopy of both eyes, angioid streaks were detected. On fluorescencin angiography, hyperfluorescence of streaks without signs of choroidal neovascularization were seen. Skin lesions (small yellowish papules) similar to pseudoxanthoma elasticum were detected on the neck and antecubital area.Conclusion: Both angioid streaks and skin lesions are manifestations of elastic tissue abnormality which may be the result of inflammatory and oxidative reactions in this hemoglobinopathy.

Purpose: To report three cases of Alport syndrome in one family with anterior lenticonus and retinal flecks.Patients and findings: Three members of one family with consanguineous parents are presented who had renal and ocular involvement. They had anterior lenticonus and a beaten bronze appearance in the macula. Reduced visual acuity and photophobia were the chief complaints of these patients.Despite correction of her refractive error, one of them underwent clear lens extraction with intraocular lens implantation due to severe impairment of visual acuity. Two patients had severe renal failure with subsequent renal transplantation. Biopsy of one of them confirmed the diagnosis of Alport syndrome.Conclusion: Despite the rarity of ocular involvement in Alport syndrome, especially in females, all three patients had anterior lenticonus and retinal flecks. Regardless of macular involvement, the main cause of decreased visual acuity was lenticular anomaly. Clear lens extraction with intraocular lens implantation was an effective treatment modality in these patients.

Purpose: To present 2 cases of acanthamoeba keratitis diagnosed by confocal scanning before positive results of smear and culture, and their successful treatment with combined medical therapy and corneal epithelial debridment.Patients and Findings: Confocal scan was carried out in 2 contact lens wearers with a clinical diagnosis of acanthamoeba keratitis followed by corneal epithelial debridment for debulking of the corneal lesion and preparing specimens for smear and culture. Medical therapy was initiated subsequently. Wet mount preparations of the contact lens preservative fluid was also evaluated under dark field microscopy. Confocal scan in both patients revealed reflective round to oval-shaped structures 15 to 25µ in diameter in the sub-epithelial and anterior stromal areas. Smear and culture results were positive for acanthamoeba and the motility of the trophozoites was easily observed using wet mount preparations. Both cases were treated successfully by combined medical therapy and debulking of the lesion.Conclusion: Confocal scan is a very helpful, non-invasive procedure in the early diagnosis of acanthamoeba keratitis before positive results of smear and culture. Corneal epithelial debulking in the early stages of acanthamoeba keratitis is of diagnostic value and has high therapeutic importance when combined with anti-acanthamoeba medical therapy.