BINA
Year:2010 | Volume:16 | Issue:1 (62)|Papers Count:18

Iran enjoys a glorious history in medicine, ophthalmology and optics and has introduced several great physicians and ophthalmologists to the world. The history of ophthalmology dates back to 6000 years ago; unfortunately we have no manuscripts or petrographies from those eras. The oldest document about ophthalmic diseases can be found in Avesta. Furthermore, as early as 1600 years ago, Genta Shapirta or Gundishapur revolutionized all sciences including ophthalmology. In this paper, the history of remarkable Iranian physicians in the field of ophthalmology is reviewed. In addition, new ophthalmic departments are briefly introduced.

Purpose: To evaluate the effect of posterior residual stroma on visual function after unsuccessful Anwar's deep anterior lamellar keratoplasty (DALK).Methoods: In this parallel historical cohort, visual acuity and refractive status were evaluated after Descemetic DALK (group 1) and compared with those of pre-Descemetic DALK (group 2).Results: One hundred and ten keratoconic eyes were enrolled. A bare Descemet’s membrane (DM) was successfully achieved in 93 (84.5%) eyes in group (1) and 17 (15.4%) eyes in group (2). Mean follow-up period was 20±8 and 20±7 months in groups (1) and (2), respectively (P= 0.08). Postoperative best spectaclecorrected visual acuity (BSCVA) was significantly better in group (1) than in group (2) at 1, 3, 6 and 12 months. However, there was no significant difference between study groups at final examination. The two groups were comparable in terms of keratometric astigmatism and spherical equivalent refractive error throughout the follow-up period.Conclusion: Retention of posterior corneal stroma delays visual recovery after DALK using Anwar's technique; however, both descemetic and pre-descemetic methods have acceptable and comparable visual acuity levels at final follow-up.

Purpose: To determine peripapillary retinal nerve fiber layer (RNFL) thickness by three-dimensional optical coherence tomography (3D-OCT) in a normal Iranian population and to evaluate the concordance of these measurements with those obtained by the second generation of optical coherence tomography (OCT II). Methods: In a cross-sectional observational study, 96 normal Iranian subjects 20-53 years of age were enrolled. Peripapillary RNFL thickness in one randomly selected eye of each subject was measured by 3DOCT and also by OCT II. Standard achromatic perimetry, corneal pachymetry and A-scan ultrasonographic biometry were also performed. Other study variables included age, gender, laterality (right versus left eye), refractive error, corneal diameter and disc area.Results: Mean peripapillary RNFL thickness measured by 3D-OCT (75.50±8.38 mm) was significantly less than that measured by OCT II (144.10±33.32 mm) (P<0.001). Using 3D-OCT, no significant difference in peripapillary RNFL thickness was observed by gender (P=0.90) or laterality (P=0.17); RNFL thickness had no correlation with age (P=0.95), axial length (P=0.32), spherical equivalent refractive error (P=0.21), central corneal thickness (P=0.66) and disc area (P=0.31). However, a positive correlation was found between peripapillary RNFL thickness and corneal diameter (P=0.03).Conclusion: 3D-OCT seems to yield lower RNFL thickness values as compared to OCT II. It seems advisable to obtain separate baseline measurements when using different generations of OCT machines.

Purpose: To evaluate the distribution of TNF-alpha promoter -1031T/C and -308G/A polymorphisms in an Iranian population with Behcet disease and ocular manifestation.Method: We investigated the distribution of TNF-alpha promoter -1031T/C and -308G/A polymorphisms in 53 patients with Behcet disease (BD) and 79 matched healthy controls, using the PCR-RFLP technique. All subjects were from an Iranian Azeri population.Results: The frequency of the TNF-alpha -308G/A polymorphism was similar in BD patients and healthy controls (P= 0.234) whereas the frequency of the TNF-alpha-1031T/C polymorphism was different between two groups (P= 0.0006). The frequency of the CG haplotype was significantly higher (P< 0.0001), and that of the TA haplotype was significantly lower in BD patients than healthy controls. Different TNF-a-1031T/C and TNF-a-308G/A polymorphisms were not associated with ocular involvement.Conclusion: TNF-alpha is a susceptibility gene for BD in Iranian patients of Azeri ethnicity. There was no relation between different haplotypes in the investigated genetic region in this group of BD patients with ocular manifestation.

Purpose: To evaluate the clinical features, and functional and anatomical outcomes of surgical intervention for pediatric rhegmatogenous retinal detachment (RRD).Methods: In this retrospective case series, pediatric patients with RRD who had undergone surgical intervention were included. Cases were categorized into five main etiological groups: congenital or developmental (48 eyes), traumatic (54 eyes), myopia alone (12 eyes), previous ocular surgery (10 eyes), and miscellaneous (3 eyes). Patients’ demographics, clinical, and surgical outcomes, as well as fellow eye findings were evaluated.Results: One hundred and twenty-seven eyes of 108 patients (mean age: 12.1±4.1 years, 80.6% male) were included. Scleral buckling and vitrectomy were the initial procedures in 31% and 63% of eyes, respectively. Mean follow-up was 34±21 (median 33) months. Retinal re-attachment at final follow-up was achieved in 74.9% of eyes. Visual acuity was> 20/200 in 14% of eyes preoperatively and in 47.9% of eyes at final followup (P = 0.001). Retinal pathologies (mostly lattice degeneration) were noted in 82.2% of fellow eyes.Conclusion: Trauma and congenital-developmental anomalies were the leading causes of pediatric RRD in this study. Despite the complexity of RRD and presence of vision-threatening anomalies, anatomic and functional outcomes were acceptable. Regular ophthalmoscopic examinations of the fellow eye are recommended for at risk children.

Purpose: Controversy has recently risen about the presence of compensatory ocular countertorsion (COCT) after head tilt. This study was performed to define the functional range of this phenomenon. Methods: Cycloplegic autorefraction was performed on 80 eyes with regular astigmatism 2D. Objective autorefraction was performed in normal position; right and left head tilt positions of 5°, 10°, 15°, 20°, and 25°. Any change in astigmatic axis after head tilt was considered as COCT defect. The authors designed a tiltometer which was fixed over the patient’s head without disturbing proper refractometry in various head positions. Enrolled eyes had no other ocular disease except refractive error. Results: Seventy eyes completed the study process. Mean age of the patients was 26.5±10 (15-48) years. Mean amplitude of COCT was 1.87°±1.81 (0°-5°) at 5° and 6.91°±4.96 (0°-20°) at 25° head tilt angles. COCT values with left head tilt were significantly lower than COCT values with right head tilt (P<0.026). Incyclotorsional compensation in each eye was not necessarily equal to the excyclotorsional compensation of the fellow eye, but this torsional discrepancy was not overal significant (P>0.237).Conclusion: COCT was found to be an unreliable phenomenon. Any minimal head tilt can induce erroneous measurement of astigmatic axis during refractometry.

Purpose: To compare the results of conventional hang-back technique (CHBT) with that of anchored hangback technique (AHBT) for bilateral lateral rectus (LR) recession in patients with exotropia.Methods: In this randomized clinical trial, 60 patients underwent CHBT (group 1) or AHBT (group 2) for LR recession (30 patients in each group). Preoperative and postoperative deviation, age, sex, the amount of recession and complications were compared between the two groups during follow up.Results: Mean age was 14.2±10.3 (3-42) and 11.5±9.3 (3-42) years in groups 1 and 2, respectively. Mean preoperative distance and near deviation in group one were 35±7.0 PD and 34.6±6.8 PD; corresponding figures in group two were 34.6±7.1 PD and 33.3±7.7 PD, respectively. Mean postoperative deviation at near and distance were 8 ± 9.4 PD and 7.2±9.1 PD in group one and 8.7±7.8 PD and 8.1±7.5 PD in group two, respectively (P=0.48 and 0.98 for distance and near). At final examination, 63.3% of subjects in group one and 60% of cases in group two were within 10 PD of orthophoria. Serious complications including globe perforation, A and V patterns and vertical deviations were not observed. There was no statistically significant difference between the two groups in terms of success rate (P=0.79) and complications. Conclusion: The success rate of both CHBT and AHBT for lateral rectus recession is comparable and favorable in patients with exotropia.

Purpose: To investigate the relationship between higher-order aberrations (HOAs) and contrast sensitivity function (CSF) in myopes.Methods: In this cross-sectional study, HOAs and CSF were measured in myopic eyes over a 6-mm pupil. Pupil diameter was measured in photopic condition. The correlation between HOAs and CSF was investigated using multivariate linear regression analysis.Results: Seventy right myopic eyes of 70 subjects with a mean age of 26.6±5.7 years were studied. Mean spherical equivalent (SE) and refractive astigmatism were -4.97±1.6 D and 0.93±0.5 D, respectively. AULCSF was significantly but indirectly correlated with cycloplegic SE (R2=0.57, P=0.02), the root mean square (RMS) of total HOA (R2=0.065, P=0.03), 4th-order aberration (R2=0.089, P=0.015) and spherical aberration (R2=0.037, P=0.004). AULCSF had no significant association with age, photopic pupil diameter, refractive astigmatism, and RMS of coma aberration.Conclusion: Spherical and 4th-order aberrations significantly affect contrast sensitivity function. However, other factors such as neural elements of visual pathway may have a role.

Purpose: To compare the visual outcomes and complications of phacoemulsification surgery in patients with and without vitreous loss (VL).Methods: A historical cohort study was performed on patients attending Labbafinejad Hospital who had underwent phacoemulsification surgery and was complicated by VL from April 2006 to March 2007. A control group was selected randomly from patients with uncomplicated phacoemulsification surgery during the same period. Best corrected visual acuity (BCVA) and posterior segment complications of phacoemulsification surgery were compared between these two groups using SPSS 15. Results: The VL group included 70 cases; among them, BCVA was 20/40 or better in 39 (56%) cases. Seventy nine patients entered the control group; of whom, BCVA was 20/40 or better in 62 (78%) cases (P<0.001). In the VL group, 4 patients developed cystoid macular edema (CME) and 6 patients developed clinically significant macular edema (CSME) while in the control group only 2 patients developed CME (P<0.05). Furthermore, 4 patients developed rhegmatogenous retinal detachment (RRD) in the VL group while there were no cases of RRD in the control group (P<0.05). Conclusion: Vitreous loss during phacoemulsification surgery reduced postoperative BCVA significantly. The rate of postoperative CME and RRD was also significantly higher with this condition.

Orbital lynphangioma is a low-flow or no-flow vascular malformation. It is a congenital and isolated hemodynamic lesion in which the clinical presentation and onset are related to orbital, peri-orbital or intracranial involvement. In addition, history of previous trauma and upper respiratory tract infection are important predictor factors. High resolution MRI, Doppler ultrasound and CT-scan are useful for diagnosis. Observation is the preferred method of management except for lesions with visual loss and cosmetic problems. Treatment methods depend on individual clinical and paraclinical manifestations of each patient.

Purpose: To report a case of lymphangioma in the lacrimal gland. Case Report: A 6-year old boy with acute proptosis and inferonasal displacement of the globe was referred. In CT-Scan revealed a heterogenous enlargement of the lacrimal gland. Steroid therapy did not lead to a significant improvement. During surgical exploration, a dark black liquid was extracted from the site of the lacrimal gland and pathology confirmed lymphangioma of the lacrimal gland. Clinical signs and symptoms improved after surgery and no recurrence has occurred up to one year. Conclusion: Lymphangioma must be considered as a differential diagnosis in acute enlargement of the lacrimal gland especially in a child or young patient.

Purpose: To present a case of Pseudoxanthoma Elasticum (PXE) with ocular involvement and visual loss. Case report: A 36 year old male presented with severe visual loss since 2 years ago. On funduscopy peau d’orange appearance and angioid streaks were evident. The diagnosis of PXE was confirmed by skin biopsy of papular lesions on the neck.Conclusion: Ocular findings may be helpful in the diagnosis of this multisystem disease.