Unifocal langerhans cell histiocytosis simulating a limbal papilloma

To report a rare presentation of unifocal Langerhans cell histiocytosis [LCH] simulating a limbal papilloma. A 24-year-old man presented with a limbal mass in his left eye which had initially been suspected to be a papilloma based on clinical findings. The mass was excised and a histopathological diagnosis of "acute bullous inflammation with granulation tissue" was made. The lesion relapsed 10 months later which necessitated repeat resection along with corneoscleral patch grafting. Histopathological studies of the excised lesion led to a final diagnosis of LCH. To the best of our knowledge, this is the second report of a rare presentation of LCH in the limbus which recurred after excision of the primary mass. The recurrent lesion was diagnosed based on histopathology and managed accordingly.

Intraocular lens power calculation after corneal refractive surgery

Purpose: To report refractive outcomes following phacoemulsification [PE] and posterior chamber intraocular lens [PCIOL] implantation in eyes with previous corneal refractive surgery

Methods: In this retrospective comparative study, 18 consecutive eyes of 14 patients with previous keratorefractive surgery for myopia including photorefractive keratectomy [PRK, 6 eyes; 33.3%] and laser in situ keratomileusis [LASIK, 12 eyes; 66.7%] underwent PE+PCIOL. Computerized corneal topography was employed to determine the flattest keratometric reading within the 3-mm central zone. This value was inserted into the Sanders-Retzlaff-Kraff/T [SRK/T] formula to calculate IOL power. IOL power selected for implantation was 1 D greater than the calculated value described above

Results: Mean age and follow-up period were 54.1 +/- 11.5 years and 29.9 +/- 26.3 months, respectively. Mean implanted lens power was 18.56 +/- 3.86 D which was not significantly different from mean back-calculated IOL power for target refraction [19.04 +/- 4.16 D] [P=0.28]. There was no significant difference between mean target refraction [-0.94 +/- 0.52 D] and achieved postoperative spherical equivalent refractive error [-0.62 +/- 1.06] at final follow-up [P=0.28]. The achieved spherical equivalent refractive error was within +/- 0.50 D of intended refraction in 8 [44.4%] eyes, within +/- 1.0 D in 11 [61.1%] eyes, and within +/- 2.0 D in 16 [88.9%] eyes. In a subgroup of patients [5 eyes] with complete pre-refractive surgery data, the difference between post-refractive surgery keratometry method and all other methods [P=0.02] and between the current method and the Feiz-Mannis method [P=0.01] was statistically significant

Conclusion: The method suggested herein is simple and independent of pre-refractive surgery data with results comparable to other commonly used methods

Bilateral Terrien's marginal degeneration and posterior polymorphous dystrophy in a patient with rheumatoid arthritis

Purpose: To report an interesting case of concomitant bilateral Terrien's marginal degeneration-like corneal ectasia and posterior polymorphous corneal dystrophy in a young man with quiescent rheumatoid arthritis

Case Report: A 24-year-old man with history of rheumatoid arthritis presented with bilateral decreased vision since four years ago. Slit lamp examination revealed bilateral circumferential peripheral corneal thinning and bulging with vascularization and lipid deposition in addition to band-like lesions in descemet's membrane. Previous records revealed no gross corneal abnormalities up to 4 years ago. Corneal lesions were compatible with bilateral circumferential Terrien's marginal degeneration concomitant with posterior polymorphous dystrophy

Conclusion: To our knowledge, this is the first report of concomitant bilateral Terrien's marginal degeneration with peripheral corneal ectasia and posterior polymorphous dystrophy in a patient with rheumatoid arthritis. Bilateral circumferential involvement, younger age at presentation and total peripheral corneal ectasia as observed in this case are not typical for classic Terrien's marginal degeneration

Causes of Visual Impairment among Patients Referred to a Visual Rehabilitation Clinic in Iran

PURPOSE: Epidemiologic evaluation and investigating the causes of visual impairment in any society is a matter of concern and has a direct effect on the country's health care planning. In this study we describe causes of low vision and blindness in Iranian patients referred to rehabilitation clinics for taking vision aids. METHODS: In this cross-sectional study, visual acuity was classified based on best-corrected visual acuity in the better eye according to the World Health Organization definition (blindness, visual acuity [VA] < 20 / 400; severe visual impairment, VA < 20 / 200-20 / 400; mild to moderate visual impairment, VA < 20 / 60-20 / 200). The causes of blindness and low vision were determined using the 10th version of International Classification of Diseases based on the main cause in both eyes. To describe data, we used mean +/- SD and frequency. RESULTS: The study included 432 patients, 65% male, with a mean age of 43.6 +/- 25.5 years (range, 3 to 92 years). Mild to moderate visual impairment, severe visual impairment and blindness were present in 122 (28.8%), 196 (46.4%) and 105 (24.8%) of the patients, respectively. The main causes of visual impairment were retinal and choroidal diseases (74.5%), optic nerve and optic tract diseases (9.8%), vitreous and globe disorders (5.3%), congenital cataract (3.1%), and glaucoma (2.6%). The distribution pattern of the causes was similar in all age subgroups. CONCLUSIONS: Diseases of the retina and choroid are the main cause of visual impairment among patients referred to an academic visual rehabilitation clinic in Iran.

Immunologic corneal graft rejection after administration of topical latanoprost: a report of two patients

To report endothelial corneal graft rejection after administration of topical latanoprost eye drops. Two eyes of two patients with a history of multiple intraocular procedures prior to penetrating keratoplasty developed endothelial graft rejection one month after administration of topical latanoprost. Cystoid macular edema developed simultaneously in one patient. Latanoprost may trigger endothelial graft rejection in susceptible eyes

Dry eye syndrome

Our understanding of keratoconjunctivitis sicca [KCS], also known as dry eye syndrome, has been changed over recent years. Until lately, the condition was thought to be merely due to aqueous tear insufficiency. Today, it is understood that KCS is a multifactorial disorder due to inflammation of the ocular surface and lacrimal gland, neurotrophic deficiency and meibomian gland dysfunction. This change in paradigm has led to the development of new and more effective medications

Indications for corneal transplantation at a tertiary referral center in Tehran

To report the indications and techniques of corneal transplantation at a tertiary referral center in Tehran over a 3-year-period. Records of patients who had undergone any kind of corneal transplantation at Labbafinejad Medical Center, Tehran, Iran form March 2004 to March 2007 were reviewed to determine the indications and types of corneal transplantation. During this period, 776 eyes of 756 patients [including 504 male subjects] with mean age of 41.3 +/- 21.3 years underwent corneal transplantation. The most common indication was keratoconus [n=317, 40.8%], followed by bullous keratopathy [n=90, 11.6%], non-herpetic corneal scars [n=62, 8.0%], infectious by corneal ulcers [n=90, 11.6%], non-herpetic corneal scars [n=317, 40.8%] followed by bullous keratopathy [n= 61, 7.9%], previously failed grafts [n=61, 7.9%], endothelial and stromal corneal dystrophies [n=28, 3.6%], and trachoma keratopathy [n=26, 3.3%]. Other indications including Terrien's marginal degeneration, post-LASIK keratectasia, trauma, chemical burns, and peripheral ulcerative keratitis constituted the rest of cases. Techniques of corneal transplantation included penetrating keratoplasty [n=607, 78.2%], deep anterior lamellar keratoplasty [n=108, 13.9%], conventional lamellar keratoplasty [n=44, 5.7%], automated lamellar therapeutic keratoplasty [n= 8, 1.0%], and Descemet stripping endothelial keratoplasty [n=6, 0.8%] in descending order. The remaining cases were endothelial keratoplasty and sclerokeratoplasty. In this study, keratoconus was the most common indication for penetrating keratoplasty which was the most prevalent technique of corneal transplantation. However, deep anterior lamellar keratoplasty is emerging as a growing alternative for corneal pathologies not involving the endothelium

Meensmann corneal dystrophy; a clinic-pathologic, ultrastructural and confocal scan report

To report the microstructural features of Meesmann corneal dystrophy [MCD] in two patients. The first patient was a 10-year-old boy who presented with bilateral visual loss, diffuse corneal epithelial microcystic changes, high myopia and amblyopia. With a clinical impression of MCD, automated lamellar therapeutic keratoplasty was performed in his left eye. Histopathologic examination of the corneal button disclosed epithelail cell swelling and cyst-like intracytoplasmic inclusions. The cells contained moderate amounts of periodic acid-Schiff-positive and diastase-sensitive material [glycogen]. Transmission electron microscopy revealed numerous vacuoles and moderate number of electron-dense membrane-bound bodies in the cytoplasm, similar to lysosomes, some engulfed by the vacuoles. The second patient was a 17-year-old female with a clinical diagnosis of MCD and episodes of recurrent corneal erosion. On confocal scan examination of both corneas, hyporeflective rond-shaped areas measuring 6.8 to 41.4 micro m were seen within the superficial epithelium together with irregular and ill-defined high-contrast areas in the sub-basal epithelial region. The subepithelial nervous plexus was not visible due to regional hyperreflectivity. This case report further adds to the microstructural features of Meesmann corneal dystrophy and suggests confocal scan as a non-invasive method for delineating the microstructural appearance of this rare dystrophy

Risk factors for posterior capsule rupture and vitreous loss during phacoemulsification

To determine the rate and risk factors of vitreous loss during phacoemulsi-fication in patients with cataracts operated by ophthalmology residents and fellows at Labbafinejad Medical Center. This prospective descriptive study included consecutive patients with cataracts undergoing phacoemulsification over a one year period. All patients were operated under local or general anesthesia using the divide and conquer technique. Preoperatively, all patients underwent a complete ocular examination including measurement of visual acuity, slitlamp biomicroscopy, intraocular pressure measurement, and dilated funduscopy. Main outcome measures included the rate of posterior capsular rupture and vitreous loss as well as associated risk factors such as surgical experience, ocular and systemic conditions, and type and severity of the cataract. Overall, 767 eyes of 767 patients with mean age of 63.7 +/- 10.3 [range, 25-91] years were operated. The overall rate of vitreous loss was 7.9% which was 5-fold greater in the hands of residents as compared to fellows. Among different factors, older age, female sex, small pupil, small capsulorrhexis, presence of pseudoexfoliation, and high myopia were significantly associated with vitreous loss. The highest rate of vitreous loss occurred in patients with dense nuclear cataracts. Considering the higher rate of vitreous loss in patients operated by ophthalmology residents; patients with known risk factors for vitreous loss should better be operated by more experienced surgeons

Lensectomy and PCIOL implantation with versus without posterior capsulotomy and anterior vitrectomy for pediatric cataracts

To compare the visual outcomes and complications of lensectomy and posterior chamber intraocular lens [PCIOL] implantation with or without posterior capsulotomy and anterior vitrectomy in older subjects with pediatric cataracts. Seventeen eyes of 12 children aged 10 to 15 years with congenital or developmental cataracts were randomly divided to two groups. Lensectomy and PCIOL [Alcon Acrysof MA60 AC] implantation was performed with [8 eyes] or without [9 eyes] posterior capsulotomy and anterior vitrectomy. Mean age at the time of surgery was 12.3 +/- 1.5 [range 10-15] years and mean follow-up period was 18.7 +/- 11.2 [range 6-36] months. Posterior capsule opacification developed in three eyes in the non-vitrectomy group; however, media opacification was mild and capsulotomy was not required in any case. All eyes in the vitrectomy group had a clear visual axis at final follow-up [P=0.2]. No significant difference was observed between the two groups in term of visual acuity [P = 0.3] or complications. Although posterior capsulotomy and anterior vitrectomy seems to be safe in pediatric cataract surgery, it may not be necessary as a routine procedure in older children

Steroid induced ocular hypertension following myopic photorefractive keratectomy

To determine the incidence of steroid induced ocular hypertension following myopic photorefractive keratectomy [PRK]. Myopic PRK was performed on 506 eyes of 269 patients. Preoperatively, spherical equivalent refractive error ranged from -1.00 to -5.00 diopters [D] and cylinder was less than 4 D. Baseline intraocular pressure [IOP] before PRK and at different time intervals after the procedure was measured by Goldmann applanation tonometry. IOP readings were corrected according to central corneal thickness as measured by Orbscan pachymetry. For the purpose of the study, corrected IOP >21 mmHg was considered as ocular hypertension. Ocular hypertension developed in 40 [7.9%] eyes overall, which occurred in 16 eyes [40%] 2-3 weeks postoperatively [mean IOP = 23.5 +/- 3.0mmHg], in 20 eyes [50%] after 4-6 weeks [mean IOP = 25.1 +/- 4.2 mmHg] and in 4 eyes [10%] 8-12 weeks following PRK [mean IOP = 29.0 +/- 3.1 mmHg]. There was no correlation between the level of IOP rise and preoperative spherical equivalent refractive error. IOP recovered to normal in all eyes after discontinuation of topical steroids and initiation of anti-glaucoma medications. Mean duration of IOP normalization was 28.5 +/- 27.7 [range 7-108] days and no instance of steroid-induced glaucoma was observed in any patient. Topical steroids may cause ocular hypertension following PRK. Early detec-tion, prompt treatment and close follow-up are recommended. We suggest measuring IOP in post-PRK patients no later than 10 to 14 days after initiation of corticosteroid treatment

Cataracts in diabetic patients: a review article

The number of people with diabetes mellitus is increasing and cataracts are one of the most common causes of visual impairment in these subjects. Advances in cataract surgical techniques and instrumentation have generally improved the outcomes; however, surgery may not be safe and effective in certain individuals with pre-existing retinal pathology or limited visual potential. This review article aims to address different aspects surrounding cataracts in diabetic patients. In a computerized MEDLINE search, relevant studies were selected by two authors using the keywords "diabetes mellitus", "cataract", "diabetic retinopathy" and "diabetic maculopathy"

Corneal involvement in xeroderma pigmentosum; a histopathologic report

To report the histopathologic features of corneal involvement in a patient with xeroderma pigmentosum [XP]. A 19-year-old man with XP presented with bilateral corneal leukoma and decreased visual acuity predominatly in his right eye. Penetrating keratoplasty was performed in the right eye due to severe corneal opacity, vascularization and lipid deposition. The corneal button underwent histopathologic evaluation which disclosed chronic interstitial lipogranulomatous keratitis. To our knowledge, this is the first report of corneal involvement in xeroderma pigmentosum from Iran describing the histopathologic features in this rare condition

External ocular manifestations in autosomal dominant dystrophic epidermolysis bullosa; a case report

To present a case of autosomal dominant dystrophic epidermolysis bullosa with symblepharon formation due to eye rubbing. A 10-year-old girl suffering from blistering and ulcerative lesions of the trunk and palms and dystrophic nails since childhood was referred to our clinic with a symblepharon connecting the medial portion of the right upper lid to the superonasal quadrant of the cornea. The central cornea in both eyes exhibited mild subepithelial opacification. She had history of eye rubbing due to foreign body sensation in the right eye, resulting in red eye and blister-like conjunctival lesions since three years ago. She had previously undergone surgical symblepharon removal leading to more severe recurrence of the condition. Dominant dystrophic epidermolysis bullosa may be accompanied by external ocular manifestations. Protection of the eye from minor trauma such as rubbing may help prevent ocular complications

Early results of autologous cultivated limbal stem cell transplantation in total limbal stem cell deficiency

To report the early results of transplantation of autologous limbal stem cells cultivated on amniotic membrane [AM] in patients with total unilateral limbal stem cell deficiency [LSCD]. Four eyes of 4 patients with total unilateral LSCD confirmed with impression cytology underwent transplantation of autologous limbal stem cell cultivated on AM. At each follow up visit, a complete eye examination with special attention to recurrence or regression of vascularization, corneal opacification, and epithelial defect healing was performed. Digital imaging was performed at each follow up visit. Impression cytology was repeated in all cases after surgery. The patients were followed for 5-13 months. Visual acuity improved in all cases. Decrease in corneal opacification and vascularization was obvious in 3 cases with coverage of the cornea with corneal epithelium. Sectoral conjunctivalization was evident in these 3 cases, however the corneas were ready for transplantation. The procedure failed in one case with total corneal conjunctivalization. Transplantation of autologous stem cells cultivated on AM seems to be an effective way for total LSCD. More definite judgment needs longer follow up together with long-term results of corneal transplantation in these patients