BINA
Year:2011 | Volume:16 | Issue:2 (63)|Papers Count:22

Purpose: To evaluate the association between hyperlipidemia with severity of diabetic retinopathy in patients with type I diabetes mellitus referred to the Eye Clinic at Imam Khomeini Hospital, Ahvaz, Iran. Methods: This observational cross-sectional study included 52 patients with type I diabetes mellitus. Fasting blood samples for analysis of serum lipids and HbAlC were obtained from all patients. Comprehensive eye examination was performed and the stage of diabetic retinopathy was determined. Result: Patients included 27 (52%) male and 25 (48%) female subjects with mean age of 21.6±4.6 (range, 15-32) years. One way ANOV A showed that higher serum levels of triglyceride, total cholesterol, and LDL cholesterol as well as a lower level of HDL cholesterol were significantly associated with increasing severity of retinopathy. After ordinal logistic regression, serum levels of LDL and HDL cholesterol had no association with the degree of diabetic retinopathy, while serum levels of triglyceride and total cholesterol were significantly associated with increasing severity of the retinopathy. No association was found between HBAIC and the severity of retinopathy. Conclusion: Higher serum levels of total cholesterol and triglyceride seem to be associated with more severe diabetic retinopathy in patients with diabetes mellitus type I but LDL cholesterol, HDL cholesterol and HbAlC do not predict the severity of diabetic retinopathy.

Purpose: To compare the visual and anatomical outcomes and complications of two surgical methods in patients with pseudophakic / aphakic retinal detachment (PARD) using Propensity Score Analysis. Methods: In this study, the propensity score matching was used as a new approach to control confounding factors. Propensity score was calculated using the STATA.9 software. Standardized difference was used to compare the distribution of important factors between the two groups. Results: Final analysis was performed on 150 patients including 62 subjects with and 88 subjects without an encircling band. Based on estimated propensity score, 51 subjects from each group were matched with 51 others. There were no statistically significant differences between the two surgical methods regarding the primary outcome measures (retinal reattachment rate and best-corrected visual acuity at 1, 2 and 4 months).The rate of cystoid macular edema was also the same in both groups at all follow-up examinations but the chance of macular pucker was significantly lp. gher in the vitrectomy without band group at the four month examination (OR=0.1428, P-value=0.034).Conclusion: In the management of PARD, based on propensity score analysis and classical methods, vitrectomy with and without encircling band have comparable results but the chance of macular pucker seems to be higher in eyes undergoing vitrectomy without any encircling band during short-term follow up.

Purpose: To explore any association between human papilloma virus (HPV) infection and ocular surface squamous neoplasia. Methods: Forty pathological specimens including 20 cases of conjunctival intra-epithelial neoplasia grade I (CIN I) and 20 cases of CIN III and invasive squamous cell carcinoma (SCC) together with 20 pterygium samples (controls) were analyzed by polymerase chain reaction (PCR) to find any evidence of HPV infection. The examinations were performed on cut sections of paraffin embedded tissue blocks from our laboratory archive. Results: Mean age of patients at the time of sampling was 56±8 (range, 30-86) years in the CIN I group; 61.7±9 (range, 43-82) years in the CIN III and SCC group and 41.5±10 (range, 24-67) years in the pterygium group. All specimens were negative for HPV. Conclusion: No association was found between HPV infection and ocular surface neoplasia in our series.

Purpose: To compare central corneal thickness (CCT) measured by Galilei and Orbscan II with that by ultrasonic (UIS) pachymetry in unoperated eyes. Methods: CCT was measured in 184 unoperated eyes of 92 healthy retractive surgery candidates using Galilei, Orbscan II, and U/S pachymetry. Considered as a benchmark, measurements by U /S pachymetry were compared to those obtained by the other two devices. Agreement between the three instruments was assessed using regression analysis, mountain plots, and Bland-Altman plots. Results: Mean CCT was 544.4±33.4 mm, 546.7±37.9 mm, and 555.8±29.6 mm, as measured by ultrasonic pachymetry, Orbscan II, and Galilei systems, respectively. Mean differences between readings measured by U /S pachymetry and those measured by Orbscan II (acoustic coefficient 0.96) and Galilei were 2.3 mm and 10.2 mm, respectively. Despite this discrepancy, Galilei had a better agreement with U /S pachymetry as compared to Orbscan II (correlation coefficient of 0.947 vs 0.817). Considering acoustic coefficient of 0.98 for Galilei, its CCT readings were more similar to U /S pachymetry. Conclusion: Galilei is well correlated with U/S pachymetry for measurement of CCT in normal eyes and by applying an acoustic coefficient of 0.98 for Galilei, its records can be considered equivalent to U/S pachymetry. Further investigations are required to address its accuracy in abnormally thin corneas such as corneal ectasia and after refractive surgeries.

Purpose: To evaluate the correlation between corneal power and corneal horizontal white to white diameter in myopic patients scheduled for LASIK surgery. Methods: Overall, in 840 eyes of 420 myopic subjects scheduled for LASIK, horizontal white to white diameter and mean corneal power were obtained using Orbscan II. Pearson correlation test and regression analysis were used to detect any correlation between corneal power and corneal diameter. Results: Mean spherical equivalent refractive error was -4.56±1.4 (range, -1 to -10.75) diopter, while mean keraometeric value was 43.69±1.5 (range, 40-47.2). A significant negative linear correlation was found between corneal power and white to white diameter as follows: corneal diameter=65.79- (1.88xcorneal power); R=0.204. Conclusion: The negative linear correlation between mean corneal power and corneal white to white diameter may have clinical implications in refractive surgery for selection of a suitable microkeratome.

Purpose: To evaluate the effect of pterygium on ocular high order aberrations. Method: This study was performed on 31 eyes with pterygia and 31 normal fellow eyes. NIOEK OPO-Scan wavefront aberrometry was performed on all eyes. Root mean square (RMS) values of total high order aberrations, coma-like aberrations, sphere-like aberrations, third, fourth and fifth order aberrations, total trefoil aberrations and spherical aberrations were compared between the two eyes. According to the size of uninvolved optical zone, pterygia were classified into three groups and aberrometric parameters were evaluated in each group and compared with each other. Results: RMS of total high order aberration was significantly highet in eyes with pterygia as compared to normal fellow eyes (1.85±2.22 mm vs 0.36±0.44 mm, P=0.001). RMS values of other types of aberrations were also higher in the involved eyes except for spherical aberration. The most significant differences were found in RMS values of total trefoil (1.37 mm vs 0.25 mm, P<0.001) and total coma (0.37 mm vs 0.14 mm, P<0.001). With increasing pterygium size, RMS values of all aberrations except spherical aberration increased. Conclusion: Pterygia significantly increase higher order aberrations especially total coma and total trefoil as compared to the normal fellow eye. This effect seems to correlated with the size of the lesion.

Purpose: To evaluate the prevalence of acute ocular chemical injuries in patients referred to Labbafinejad Medical Center (LMC) over a period of one year. Methods: All patients with chemical bums referred to LMC emergency ophthalmology service were included in the study. Demographic characteristics and information regarding the bum were obtained. Visual acuity assessment and slit lamp examination were performed in all cases. The Hughes-Roper-Hall classification was used for grading the severity of ocular bums. Results: Of 25, 486 patients referred to the LMC emergency ophthalmology service over one year, 219 (0.36%) were due to chemical injuries including 179 (81.9%) male and 40 (18.3%) female subjects. Chemical injuries were more common in the 20-30 year age group which included 68 subjects (31.5%). The most common causes of chemical injury were occupational injury in 102 cases (46.6%); 119 cases (54.3%) were referred during the first hour after injury, in 99 cases (45.2%) the cause of injury was acid material and in 32 cases (14.6%) the bum was Alkaline. Grade I bum was seen in 155 cases (69.8%) and grade IV in 5 cases (2.25%). Grading of the injury was not related to the causative agent. Conclusion: The incidence of chemical bums is less than 1% of patients to referred the emergency ophthalmology service. Acids are the most common materials causing chemical eye bums and occupational accidents are the most common cause.

Purpose: To evaluate visual acuity and refractive error after deep anterior lamellar keratoplasty (DALK) using Anwar's technique in patients with post-LASIK ectasia. Methods: Pre- and postoperative data of patients who had developed ectasia after LASIK and hence underwent DALK by Anwar's technique were compared. Main outcomes measures were uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), spherical equivalent refractive error, mean keratometry and keratometric stigmatism. Results: Eleven eyes of 10 patients were included. Mean age was 31.6±7.4 years and mean follow-up period was 20.2±6.5 months. Intraoperatively, a bare Descemet's membrane was successfully achieved in all cases. Mean UCVA and BSCVA were increased from 20/400 to 20/160 (P=0.39) and from 20/160 to 20/40 (P=0.007), respectively. Mean spherical equivalent refractive error was increased from -11.53±5.4 D to -13.47±0.5 D (P=0.34). Mean keratometry and keratometric astigmatism remained unchanged. Conclusion: DALK using Anwar's technique is a safe and reproducible procedure for post-LASIK ectasia. However, a high refractive error should be expected postoperatively.

Blepharitis is the most common ocular disease encountered by an ophthalmologist constituting 37% of all ophthalmology clinics out patient visits. Blepharitis is categorized into anterior and posterior, each classified as infectious or noninfectious. Anterior blepharitis is mainly infectious and caused by Staphylococcus sp., Propyonibacterium acne, Corynebacterium sp., Moraxella catarrhalis, herpes simplex virus, Phitirus pubis and Mites. Possible mechanisms working in anterior blepharitis are colonization of lid margins by microorganisms, an imbalance between pathogenic and non-pathogenic microorganisms, and inflammatory mediators released by microorganisms or immune cells. Another form of anterior blepharitis is Seborrheic which is characterized by greasy scales on the anterior lid margin. Posterior blepharitis is mainly noninfectious and caused by alterations in the composition of meibomian secretions including an increase in free fatty acids and fatty wax leading to tear film instability, tear hyperosmolarity and evaporative dry eye. Tear hyperosmolarity is an important reason for ocular inflammation and irritation leading to epitheliopathy. In all forms of blepharitis, subjective complaints are burning and discomfort which is typically worst in the morning and improving toward the end of the day, discomfort while working on a computer, discharge, and redness. Additionally, patients may complain of contact lens intolerance or recurrent episodes of chalazia. Clinical findings vary depending on the type of blepharitis and include collarets around eyelashes, hyperemia and thickening of the lid margins, madarosis, poliosis, trichiasis, telangectasia, lid margin irregularities, and pouting and plugging of meibomian gland orifices. These abnormalities may be complicated by corneal marginal ulceration, and conjunctival or corneal phlyctenulosis. Treatment of blepharitis is aimed to reduce patient discomfort decrease, bacterial colonies and inflammation, as well as help meibomian glands release their secretions. These goals are achieved through different measures including hot, moist compresses and application of anti-bacterial and anti inflammatory agents.

Retinoblastoma is the most common primary intraocular malignancy of childhood. Current treatments for retinoblastoma have led to a survival rate exceeding 95% and only occasional long-term morbidity. Locally delivered chemotherapy could carry the benefits of chemoreductive effects and conceivably spare patients from the toxicity and mutagenicity associated with systemic chemotherapy. Mainstays of local chemotherapy are improving drug delivery to the tumor site in the eye and molecular target treatment of the tumor while sparing intact organs. In this review, chemotherapeutic drug delivery as peribulbar, intraophthalmic artery and/or intravitreal injections and finally gene therapy and use of vectors for local delivery of drugs and genes are presented. Despite many pre-clinical advanced improvements in local chemotherapeutic control of the tumors, using these methods in the clinic requires many delicate and well controlled preclinical and clinical studies.

Purpose: To present a patient with localized corneal edema due to a small retained fragment of nucleus in the anterior chamber after uncomplicated phacoemulsification. Case Report: A 74-year-old female subject with history of phacoemulsification in her right eye about 1.5 years ago complained of foreign body sensation, pain and decreased vision in the same eye. Visual acuity of that eye had decreased from 20/25 after the operation to 20/50 at the time of presentation. Slitlamp examination revealed localized stromal edema in the inferior part of the cornea accompanied with iridocorneal adhesion and a 3 mm retained fragment of lens nucleus in the anterior chamber. The fragment was removed through a clear corneal incision which resulted in improvement of the ocular pain and corneal edema.Conclusion: Retained nuclear fragments are a complication of phacoemulsification cataract surgery which can present early or late postoperatively. One should consider this complication in the approach to a patient with postoperative localized corneal edema or intraocular inflammation even if the fragment is not visible itself.

Purpose: To present a case of orbital granular cell tumor, a rare orbital tumor. Case Report: A 55-year-old woman presented with binocular diplopia and right ocular displacement. The problem had initiated 3 years ago. A firm nontender mass at the region of the right lower lid was visible. Orbital CT-scan disclosed a well-defined mass in the inferior right orbit with involvement of the inferior muscles. Subtotal excision of the mass, and histopathological and immunohistochemical studies revealed granular cell tumor. Postoperatively, there was improvement in patient's signs and symptoms. Because of residual tumor, she was referred for radiotherapy. Conclusion: Immunohistochemical and histopathological studies are beneficial in diagnosis of rare orbital tumors.

Purpose: To report a typical case of HLA-A29 positive birdshot choroidipathy as the first report in Iran. Case Report: A 43-year-old male subject without any systemic disease presented complainting of decreased visual acuity in both eyes for 5 years. Visual acuity was 20/30 in his right eye and CF at 2 meters in the left eye. Intraocular pressure was within normal limits bilaterally. Corneas and lenses were clear and no inflammation or cellular reaction was noted in the anterior chamber on slitlamp examination. The vitreous body, however showed cellular reactions. Color fundus photograph, fluorescein angiography and indocyanin green were in favor of choroidopathy. In FA multiple hyperfluorescent lesions and in ICG multiple hypofluorescent lesions were seen. He had been under treatment with oral prednisolone, cyclosporine and azathioprine during the past 5 years. Despite initial response, the disease progressed and visual loss were progressive. Regarding the course of uveitis and the fundus pattern as well as positive HLA-A29, he was diagnosed with typical birdshot choroidopathy. Conclusion: To our knowledge, this is the first report of a typical HLA-A29 positive birdshot choroidopathy in Iran. The strong association of this disease with HLA-A29 confirms the diagnosis.