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Current Ophthalmology - Volume:28 Issue: 4, Dec 2016

Journal of Current Ophthalmology
Volume:28 Issue: 4, Dec 2016

  • تاریخ انتشار: 1395/08/16
  • تعداد عناوین: 18
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  • Kouros Nouri, Mahdavi Pages 159-160
    Primary angle-closure glaucoma (ACG) is a serious ocular health care problem especially in Asia, increasing in prevalence as one moves towards the Eastern part of Asia.1 The disease causes a significant burden of blindness and visual disability in regions where it is most prevalent. With the advent of SD-OCTs, anterior and posterior segment mechanisms of the disease have been better elucidated. However, like primary open-angle glaucoma, ACG likely represents different phenotypes yet to be identified through research on the genetics. In the meantime, significant amount of ongoing research is devoted to better understanding the contribution of various well-defined mechanisms to pathophysiology of the disease in various clinically-defined ACG subtypes. The article by Moghimi et al provides us with additional information in this regard.
    The investigators enrolled 115 eyes of 115 patients roughly equally distributed into 3 groups: fellow eyes of patients with a history of acute ACG (FAAG), (chronic) primary ACG eyes (PACG), and primary angle-closure glaucoma suspects (PACS). All eyes had a thorough eye exam, A-scan biometry along with anterior segment OCT (AS-OCT) with Visante before laser peripheral iridotomy. The authors qualitatively determined the main and secondary mechanisms of narrowing of the angle based on AS-OCT images and also quantitatively compared angle parameters of interest in the 3 groups. Twenty-eight eyes were excluded because of poor image quality.
    In the qualitative analyses, they found that an exaggerated lens vault (LV), a surrogate for lens position, was more frequently the primary mechanism for the narrowing of the angle in PACG eyes as compared to FAAG and PACS eyes. The quantitative data supported these findings demonstrating that PACG eyes had a smaller iris curvature (a proxy parameter for iris bombe or pupillary block mechanism) compared to FAAG eyes (p = 0.01), while the difference of iris curvature between the PACG and PACS eyes did not reach statistical significance (p = 0.14); this difference was only slightly smaller than the one between PACG and FAAG (average of 0.05 vs 0.07 mm). Overall, the findings confirm the recent consensus that ACG is, even in individual eyes, a multifactorial disease with various mechanisms contributing to varying degrees to the narrowing of the angle.
    A caveat of the study is that many of the FAAG and PACG eyes were under treatment (average of 1.0 ± 0.7 and 1.7 ± 1.3). Treatment with medications that decrease aqueous secretion might lead to a smaller amount of aqueous being trapped behind the iris and hence lead to an underestimation of iris curvature. The PACG eyes were being treated with a larger number of medications in this study. Other issues include lack of a UBM-confirmation for the presence and magnitude of the plateau iris. Also, any of the 3 major mechanism of ACG (pupillary block, plateau iris or larger lens vault) may actually be potentiated by a thick peripheral iris roll.2 No dynamic measurements were made as all the measurements were done in the dark; a change in the iris volume with dilation and the size of pupil can be predictors of angle width.3
    One finding that is worth of mentioning is that FAAG eyes had the most unfavorable measurements for all the parameters predictive of narrowing of the angle including a shorter axial length. This could mean that a convergence of unfavorable predisposing factors in a given eye, potentially in varying degrees as shown by Moghimi et al, may be the reason such eyes develop an acute attack of ACG. No choroidal thickness measurements were made and hence the contribution of this important parameter towards a more anterior lens position with larger lens vault and potentially more anterior location of the ciliary body needs to be explored in future studies.4
    The investigators should be commended for their contribution to our understanding of ACG. It would be interesting to know the relative contribution of the remaining mechanisms once the pupillary block is removed by laser peripheral iridotomy and the authors are well positioned to make such a contribution given their existing dataset.
  • Mehdi Modarres Pages 161-162
    Diabetic retinopathy is the leading cause of visual impairment in the working age group mainly due to diabetic macular edema (DME).1 and 2
    As the incidence of diabetes is increasing in human populations, the visual burden of DME is expected to expand. The standard treatment for DME has been macular laser photocoagulation3 for almost two decades but has shifted to intravitreal injection of anti-VEGF agents over the past decade. Although the intravitreal injection of these drugs and even steroids has been shown to be superior to macular laser photocoagulation,4, 5, 6, 7, 8, 9 and 10 there is much to be desired in the treatment of DME.
    It has been suggested that attached vitreous may have an adverse effect on the clinical course of DME. Posterior vitreous detachment has been reported to be less common in eyes with DME and that attached vitreous may diminish the benefit of intravitreal steroid therapy.11 On this basis, some authors have suggested pars plana vitrectomy and removal of posterior hyaloid with or without ILM removal for treatment of DME.
    The DRCR network has reported the results of vitrectomy in cases of vitreomacular traction associated with diabetic retinopathy.12 The macular thickness significantly decreased in most eyes. Between 28% and 49% of eyes experienced improvement of visual acuity, whereas in 13%–31% the visual acuity worsened. In patients without vitreomacular traction, with or without epiretinal membranes, however, the results of vitrectomy have been more variable and the majority of studies have reported non-significant visual improvement despite initial structural improvement. Simunovic et al13 published a systematic review and meta-analysis on the outcomes of vitrectomy for DME and concluded that there is little evidence to support vitrectomy as a treatment for diabetic macular edema in the absence of epiretinal membrane or vitreomacular traction and that although vitrectomy appears to be superior to laser in its effects on retinal structure at 6 months, no such benefit has been proven at 12 months. Similar results were obtained by Jackson et al14 in their recent systematic review, meta-analysis, and synthesis of safety literature. They did not identify any major safety concerns.
    In this issue, Ghassemi et al have studied a group of 12 eyes with non-tractional epiretinal membranes associated with DME refractory to at least 2 intravitreal injections of bevacizumab and one injection of triamcinolone acetonide. Vitrectomy, membranectomy, and ILM peeling was performed in these patients which resulted in significant reduction of central macular thickness without a parallel significant improvement in visual acuity. These results are well based in literature as mentioned previously. The authors are to be commended for their study of the subgroup of eyes with non-tractional epiretinal membranes specifically, which has not been clearly reported in literature.
    Despite these findings, the role of vitrectomy in the treatment of DME without vitreomacular traction cannot be entirely ruled out. It should be considered that in many cases reported in literature, including the cases studied by Ghassemi et al, vitrectomy has been performed on eyes with longstanding macular edema. It is conceivable that such eyes have already sustained marked structural damage which makes them refractory to any kind of treatment including vitrectomy. In other words, these eyes may be refractory to vitrectomy for the very reason that they are refractory to anti-VEGF agents. It is quite likely that vitrectomy and its resultant decrease in macular edema would lead to vision improvement in eyes without much structural damage. In fact, two studies have already demonstrated a correlation between the pre-vitrectomy integrity of outer retina (external limiting membrane and ellipsoid zone) and the potential for vision improvement after vitrectomy.15 and 16 Adequately sized randomized clinical trial are needed to elucidate the role of vitrectomy on the amount and duration of visual improvement in eyes with preserved outer retina as compared to other treatment modalities.
  • Hormoz Chams Pages 163-164
    In this issue of JOCO, Moghimi et al present “Qualitative evaluation of anterior segment in angle closure disease using anterior segment optical coherence tomography”. In this prospective, cross-sectional study, one eye of 115 patients with angle closure disease was evaluated using anterior segment optical coherence tomography (AS-OCT). The patients were divided into three subgroups: fellow eye of acute angle closure (FAAC), primary angle closure glaucoma (PACG), and primary angle closure suspect (PAGS). They found a significant difference in the mechanism of this event in the three subgroups (p = 0.03). While the majority of FAAC and of PACS eyes had dominantly pupillary block mechanism in the PACG group, this phenomena was observed in only 48.7% of cases (p = 0.03). The percentage of exaggerated lens vault and plateau iris was higher in PACG group. FAAC group had the shallowest AC and greater iris curvature and lens vault which were statistically significant compared with the two other groups. The iris thickness was not significantly different in the three groups. They concluded that pupillary block was a major factor in the mechanism of primary acute angle closure glaucoma. Primary angle closure glaucoma is the most frequent cause of blindness in the world1; therefore, AS-OCT imaging can indicate which eyes should be treated before angle closure occurs.
    In the prospective, non-randomized, comparative case series, Tanbakouee and coworkers have presented their investigation “Photorefractive keratectomy for patients with preoperative low Schirmer test value”. They have compared lacrimal secretion with preoperative low and normal Schirmer cases after photorefractive keratectomy (PRK). The patients were divided in two groups. 36 eyes of 36 patients with low Schirmer test were compared with 40 eyes of 40 patients with normal Schirmer test. Post-operatively, the Schirmer values were significantly lower in both groups. However, deterioration was much greater in low Schirmer group (p = 0.012). The mechanisms for the post-PRK dryness can be multifactorial, but corneal sensory nerve damage could play a major role.2 The authors propose that the patients with dry eye should be thoroughly assessed and treated before PRK.
    Zhang and coauthors present “Corneal biomechanics after small-incision lenticule extraction versus Q-value-guided femtosecond laser-assisted in situ keratomileusis”. Their aim was to study the changes in corneal hysteresis and corneal resistance factors following small-incision lenticule extraction (SMILE) versus Q-value-guided femtosecond laser assisted in situ keratomileusis (Q-FS-LASIK). They included 80 eyes of 80 patients in each group. Corneal resistance factors were quantitatively assessed using Ocular Response Analyzer prior to operation and at 1 day, 2 weeks, and 1 and 3 months post-operatively. Both types of surgery were associated with statistically significant decrease in corneal biomechanical properties at day 1 (post-operative) p
  • Mehrdad Mohammadpour, Mojtaba Abrishami, Ahmad Masoumi, Hassan Hashemi Pages 165-169
    Purpose
    To review the background, epidemiology and current management of trachoma in endemic areas and worldwide.
    Methods
    Review of literature.
    Results
    Trachoma is one of the leading causes of preventable blindness in developing countries. It was reported as one of the seven most neglected tropical diseases that can be prevented via drug administration. Its infliction is primarily aimed at those living in areas deprived of clean water and proper sanitation. It is estimated that trachoma is the cause of visual impairment in about 2.2 million people worldwide of which about 1.2 million are completely blind. With implementation of the SAFE (surgery, antibiotics, facial cleanliness, and environmental control) strategy with support from the International Trachoma Initiative (ITI) the incidence of trachoma has decreased significantly in the Middle East and North Africa region.
    Conclusion
    With the enhancement of socioeconomic and sanitary status of people, advent of new generations of antibiotics, training of expert ophthalmologists and eye care facilities the prevalence of trachoma is decreasing.
    Keywords: Trachoma, Chlamydia trachomatis, Follicular conjunctivitis
  • Sasan Moghimi, Rebecca Chen, Nikoo Hamzeh, Nassim Khatibi, Shan C. Lin Pages 170-175
    Purpose
    To evaluate different mechanisms of primary angle closure (PAC) and to quantify anterior chamber (AC) parameters in different subtypes of angle closure disease using anterior segment optical coherence tomography (AS-OCT).
    Methods
    In this prospective study, 115 eyes of 115 patients with angle closure disease were included and categorized into three groups: 1) fellow eyes of acute angle closure (AAC; 40 eyes); 2) primary angle closure glaucoma (PACG; 39 eyes); and 3) primary angle closure suspect (PACS; 36 eyes). Complete ophthalmic examination including gonioscopy, A-scan biometry, and AS-OCT were performed. Based on the AS-OCT images, 4 mechanisms of PAC including pupillary block, plateau iris configuration, thick peripheral iris roll (PIR), and exaggerated lens vault were evaluated. Angle, AC, and lens parameter variables were also evaluated among the three subtypes.
    Results
    There was a statistically significant difference in the mechanism of angle closure among the three groups (p = 0.03). While the majority of fellow eyes of AAC and of PACS eyes had pupillary block mechanism (77.5% and 75%, respectively), only 48.7% of PACG eyes had dominant pupillary block mechanism (p = 0.03). The percentage of exaggerated lens vault and plateau iris mechanisms was higher in PACG eyes (25.5% and 15.4%, respectively). Fellow eyes of AAC had the shallowest AC (p = 0.01), greater iris curvature (p = 0.01), and lens vault (p = 0.02) than PACS and PACG eyes. Iris thickness was not significantly different among the three groups (p = 0.45).
    Conclusion
    Using AS-OCT, we found that there was a statistically significant difference in the underlying PAC mechanisms and quantitative AC parameters among the three subtypes of angle closure disease.
    Keywords: Anterior segment optical coherence tomography, Angle closure, Glaucoma, Lens vault, Iris curvature
  • Elham Tanbakouee, Mohammad Ghoreishi, Mohammad Aghazadeh, Amiri, Mehdi Tabatabaee, Mohadeseh Mohammadinia Pages 176-180
    Purpose
    To compare dry eye signs and symptoms between patients with preoperative low and normal Schirmer test after Photorefractive keratectomy (PRK).
    Methods
    In this prospective, nonrandomized, comparative case series, 76 eyes of 76 patients were preoperatively categorized into two groups according to selected criteria for characterization of tear film status: the low Schirmer test value (STV) group and the normal STV group. For the tear function assessment, we performed a Schirmer test with and without anesthesia, tear break-up time (TBUT) test, and measurement dry eye symptoms using the Farsi translation of Ocular Surface Disease Index (OSDI) questionnaire pre- and 3 months post-operation.
    Results
    Postoperatively, the Schirmer and TBUT values were significantly lower in both groups than preoperatively (all p
    Conclusion
    These results demonstrated that tear function deteriorates after PRK. Therefore, patients with low preoperative Schirmer test values should be thoroughly assessed for dry eye before proceeding with refractive surgery to eliminate postoperative complication.
    Keywords: Schirmer test, Photorefractive keratectomy, Tear function
  • Jun Zhang, Li Zheng, Xia Zhao, Yang Xu, Shu Chen Pages 181-187
    Purpose
    The aim of this study was to compare the changes in corneal biomechanical properties following small-incision lenticule extraction (SMILE) versus Q-value–guided femtosecond laser-assisted in situ keratomileusis (Q-FS-LASIK).
    Methods
    In this prospective comparative study, patients with a sphere plus cylinder measurement of less than −10.00 D and cylinder measurement of less than −5.00 D were included in the study. A total of 160 patients (160 eyes) with myopia and myopic astigmatism were divided into the two groups, with 80 patients (80 eyes) allocated to SMILE and 80 patients (80 eyes) allocated to Q-FS-LASIK. Corneal hysteresis (CH) and the corneal resistance factor (CRF) were quantitatively assessed using the Ocular Response Analyzer (ORA) preoperatively and at 1 day, 2 weeks, and 1 and 3 months postoperatively.
    Results
    Both types of surgery were associated with statistically significant decreases in CH and the CRF at postoperative day 1 (both P 0.05). Both groups showed similar biomechanical changes at each time point (all P > 0.05).
    Conclusions
    Both SMILE and Q-FS-LASIK resulted in a decrease in CH and the CRF at postoperative 1 day, with the decreases stabilizing after this point. There were no significant differences between the short term effects of SMILE and Q-FS-LASIK on corneal biomechanical properties.
    Keywords: Small incision, Q, value guided, Femtosecond, Biomechanical properties
  • Saeedeh Ghorbanhosseini, Hassan Hashemi, Ebrahim Jafarzadehpur, Abbasali Yekta, Mehdi Khabazkhoob Pages 188-193
    Purpose
    To compare the visual responses of post refractive surgery's patients using Early Treatment Diabetic Retinopathy Study Chart (ETDRS) and E-chart with and without color filters.
    Methods
    The uncorrected Logarithm of the Minimum Angle of Resolution Visual Acuity (LogMAR VA) of 70 patients with a mean age of 26.2 ± 3.76 years (from 19 to 34 years) who had undergone Photorefractive Keratectomy (PRK) (the range of post operation refractive error: ±0.5 D) was measured under the light conditions of with and without asymmetrical glare by using red, green, and yellow filters and ETDRS chart and E-chart.
    Results
    In both light conditions of with and without glare, the mean visual acuity of the three filters in the right and left eyes was significantly better with the E-chart versus the ETDRS chart (P
    Conclusions
    Visual acuity measurements were different with ETDRS chart and E-chart. These two charts cannot be used interchangeably.
    Keywords: Visual acuity charts, Refractive surgery, Colored filters, Glare
  • Fereshteh Shokrollahzadeh, Hassan Hashemi, Ebrahim Jafarzadehpur, Ali Mirzajani, Mehdi Khabazkhoob, Abbasali Yekta, Soheila Asgari Pages 194-198
    Purpose
    To determine the short-term effect of rigid gas permeable (RGP) contact lenses on corneal aberrations in keratoconic patients.
    Method
    Sixteen keratoconic eyes with no history of RGP lens wear were included. They all had corneal aberrometry using Pentacam, and different aberration indices of the anterior and posterior surfaces of the cornea were measured before and 3 months after fitting RGP lenses. The effect of baseline parameters on these changes was tested in univariate and multiple models.
    Results
    Total aberrations and individual Zernike coefficients did not show statistically significant changes after using RGP lenses. Although not statistically significant, vertical coma decreased in the anterior (p = 0.073) and posterior surface (p = 0.095). Relationships that remained statistically significant in the multiple model were between baseline central corneal thickness and changes in total higher order aberrations and anterior 4th order astigmatism 0°, and between baseline 2nd order astigmatism 45° and its changes.
    Conclusion
    In this study, corneal aberrations remained unchanged 3 months after wearing RGP contact lens. Further studies with sufficient samples in different groups of keratoconus severity or baseline aberrations are needed to obtain more accurate results.
    Keywords: Aberrometry, Keratoconus, Rigid gas permeable contact lens, Pentacam
  • Fariba Ghassemi, Fatemeh Bazvand, Ramak Roohipoor, Mehdi Yaseri, Narges Hassanpoor, Mohammad Zarei Pages 199-205
    Purpose
    To evaluate the efficacy of vitrectomy, membranectomy, and internal limiting membrane (ILM) peeling on macular thickness and best corrected visual acuity (BCVA) in patients with refractory diffuse diabetic macular edema (DME) and non-tractional epiretinal membrane (NT-ERM).
    Methods
    This prospective interventional case series included eyes with refractory DME (central subfield macular thickness [CSMT] > 300 μm) after at least two intravitreal injections of bevacizumab (IVB) and one intravitreal injection of triamcinolone (IVT), and accompanying NT-ERM. Complete ophthalmic examination, baseline spectral domain optical coherence tomography (SD-OCT), and fluorescein angiography (FA) were performed prior to 23 gauge pars plana vitrectomy with membranectomy and internal limiting membrane (ILM) peeling. Postoperative evaluation was done with clinical examination and SD-OCT. Linear mix model analysis was used to study postoperative results.
    Results
    Twelve eyes from 11 patients (5 males) with a mean age of 60.33 ± 9.01 (range 46–73 years) were included. The mean follow-up time was 13.5 ± 4.48 months (range 4–20 months). A significant reduction in CSMT was found (from 559 ± 89 μm to 354 ± 76 μm; P = 0.001), with a non-significant BCVA change (from 0.84 ± 0.32 logMAR to 0.72 ± 0.2 logMAR; P = 0.967). There was no significant correlation between CSMT and BCVA (partial correlation = −0.115, P = 0.445) and also between estimated mean CSMT change per month and estimated mean BCVA change per month (r = 0.337, P = 0.283).
    Conclusion
    In this series, our results did not show that vitrectomy, membranectomy, and ILM peeling result in significant improvement of BCVA in eyes with refractory DME and non-tractional ERM in spite of central macular thickness reduction.
    Keywords: Refractory diabetic macular edema, Epiretinal membrane, Vitrectomy, Internal limiting membrane
  • Farhad Fazel, Majid Bagheri, Khodayar Golabchi, Hamidreza Jahanbani Ardakani Pages 206-211
    Purpose
    The aim of the present study was to investigate the effect of subthreshold diode laser micropulse (SDM) in comparison with conventional laser photocoagulation in the treatment of the diabetic macular edema (DME).
    Methods
    Sixty-eight eyes from 68 patients with clinically significant DME were divided randomly into two equal groups. In the first group, SDM photocoagulation was employed, while conventional laser photocoagulation was performed on the eyes of the second group. Central macular thickness (CMT), central macular volume (CMV), and best corrected visual acuity (BCVA) were measured before, 2, and 4 months after intervention, and the results were compared.
    Results
    The mean CMT was 357.3 and 354.8 microns before the treatment in Groups 1 and 2, respectively (P = 0.85), and decreased significantly to 344.3 and 349.8 after 4 months, respectively (P = 0.012 and P = 0.049). The changes in the central macular thickness was statistically higher in the first group (P = 0.001). The mean CMV significantly decreased in Group 1 (P = 0.003), but it was similar to pretreatment in Group 2 after 4 months (P = 0.31). The BCVA improved significantly in Group 1 (P
    Conclusions
    In this study, SDM was more effective than conventional laser photocoagulation in reducing CMT and CMV and improving visual acuity in patients with DME.
    Keywords: Diabetic macular edema, Subthreshold diode laser micropulse, Conventional laser photocoagulation
  • Mohammad Taher Rajabi, Seyedeh Simindokht Hosseini, Mohammad Bagher Rajabi, Syed Ziaeddin Tabatabaie Pages 212-216
    Purpose
    To introduce a new modification of transposition flap technique for reconstruction of the medial canthal region.
    Methods
    This prospective study included 58 patients with the full thickness involvement of both upper and lower lid in the medial canthal area. Reconstruction of posterior lamella was performed by utilizing periosteal flaps and tarsoconjunctival grafts, and anterior lamellar reconstruction was performed using transposition of multiple full-thickness skin flaps, a modified form of rhomboid flap technique. Post-surgical outcomes, advantages, and drawbacks of this technique are discussed.
    Results
    Between 2010 and 2014, 58 patients with basal cell carcinoma (BCC), proven by histopathologic study, underwent medial canthal reconstruction. The mean age was 72.8 ± 8.3 years. In 30 patients, the lacrimal apparatus was excised, and periosteal flaps or tarsoconjunctival grafts were prepared to reconstruct the posterior lamella. Anterior lamellar reconstruction was performed in all patients, and the mean number of transposition flaps was 3.63 in addition to the blepharoplasty flap. Patients were followed for 24 months. None of the patients developed flap necrosis or other intraoperative and postoperative complications, with acceptable aesthetic and functional outcomes.
    Conclusion
    Full-thickness reconstruction of the medial canthal area by utilizing periosteal flaps and modified transposition flap technique all in one session can be considered an alternative method in medial canthal reconstruction, with acceptable functional and aesthetic outcomes.
    Keywords: Medial canthal reconstruction, Rhomboid, Modified transposition flap technique, Periosteal flap
  • Zhale Rajavi, Hamideh Sabbaghi, Ebrahim Amini Sharifi, Narges Behradfar, Mehdi Yaseri Pages 217-222
    Purpose
    To determine the role of Interactive Binocular Treatment (I-BiT™) as a complementary method of patching in amblyopia therapy.
    Methods
    In this randomized clinical trial study, 50 unilateral amblyopic children (25 male/25 female) between 3 and 10 years with either best corrected visual acuity (BCVA) ≤20/30 in the amblyopic eye or a difference of BCVA ≥ 2 lines between the two eyes were included. They were randomly classified into the case and control groups (25 in each). Patching was recommended in both groups, and cases also received I-BiT™. Cases were asked to play I-BiT™ games through appropriate glasses with conjugate colored filters. Moving and fixed targets were shown to the amblyopic and non-amblyopic eyes, respectively. Playing games was continued 20 min in each session for 5 days a week within one month (total time: 6.6 h). Patching was continued for one month more in both groups to evaluate the continuous effect of I-BiT™. BCVA was measured at baseline, one month after beginning I-BiT™, and one month after cessation of I-BiT™.
    Results
    BCVA of amblyopic eyes in cases and controls were 0.34 ± 0.14 and 0.33 ± 0.17LogMAR at baseline which improved to 0.17 ± 0.14 and 0.26 ± 0.17 at one month, respectively. The difference was significant in each group (p
    Conclusion
    Based on our results, I-BiT™ seems to be effective in amblyopia therapy accompanied with patching. We recommend comparing I-BiT™ alone with patching in further studies.
    Keywords: Amblyopia, Interaction Binocular Treatment (I, BiT™), Patch therapy
  • Gholamhoseyn Aghai, Parvin Dibajnia, Esmat Ashkesh, Mohammadreza Nazari, Khalil Ghasemi Falavarjani Pages 223-225
    Purpose
    To evaluate the frequency of behavioral disorders in children with significant refractive error and to compare the results with those of emmetropic children.
    Methods
    In this prospective, comparative study from January to September 2013, refractive errors of all 5–12-year-old children who referred to a general eye clinic were recorded. A validated Persian version of the Rutter A scale was filled out by the parents for the evaluation of the child's behavioral disorders. The Rutter A scale scores of children with significant refractive error were compared with those of emmetropic eyes. Student t test, Chi square test, and Fisher's exact test were used for analysis. Differences with a P value less than 0.05 were considered significant.
    Results
    One hundred eighty-three patients, including 101 patients with significant refractive error and 82 emmetropic subjects, were studied. Overall, 44 patients (24%) had behavioral disorders, according to the Rutter A scale scores. Thirty patients (29.7%) with significant refractive error and 14 emmetropic subjects (16.9%) had behavioral disorders (P = 0.043). The prevalence of behavioral disorders were 37.5% in hyperopia, 35.7% in hyperopia-astigmatism, 21.4% in simple astigmatism, 16.7% in myopia-astigmatism, and 14.3% in myopia. Compared with emmetropic subjects, the prevalence of behavioral disorders was statistically significantly higher only in patients with hyperopia and hyperopia-astigmatism (P = 0.019 and P = 0.040).
    Conclusion
    The prevalence of behavioral disorders is higher in children with hyperopia and hyperopia-astigmatism.
    Keywords: Refractive errors, Behavioral disorder, Hyperopia, Hyperopia astigmatism
  • Amir Asharlous, Ebrahim Jafarzadehpur, Ali Mirzajani, Mehdi Khabazkhoob, Samira Heydarian, Ali Taghipour Pages 226-227
    Purpose
    To evaluate tear film stability and optical aberrations in eyes wearing plano Lotrafilcon B contact lenses (CL).
    Methods
    Tear Deformation Time (TDT) and aberrometric parameters were assessed in 86 normal emmetropic eyes before and 6 h after wearing CL.
    Result
    A statistically significant decrease in TDT and increase in root mean square (RMS) values of higher order aberrations (HOA) were revealed 6 h after CL insertion (both P
    Conclusion
    Our findings indicated that the Lotrafilcon B contact lens affects HOA more than LOA. The tear film was less stable after wearing CL.
    Keywords: Tear stability, Tear Deformation Time, Aberrations, Optical quality, Silicone hydrogel contact lens
  • Masoomeh Eghtedari, Seyede Fariba Fattahi, Naser Owji, Mohammad Javad Ashraf, Mohammad Reza Khalili, Bita Geramizadeh Pages 228-231
    Purpose
    To present a rare presentation of optic nerve glioma (ONG) with total intraocular extension.
    Methods
    A 44-year-old man with a history of loss of vision since childhood and recent development of progressive disfiguring proptosis was referred.
    Results
    The vision in the affected eye was no light perception, and a proptosis of about 2–3 mm was present. Computed tomography and Magnetic Resonance Imaging (MRI) of brain/orbit showed a fusiform enlargement of the left optic nerve and total filling of vitreous cavity by a mass with high signal intensity in T2-weighted MRI. There was no extension into the intracranial cavity. The patient also had no signs of neurofibromatosis. Histopathology confirmed the diagnosis of ONG of the left orbit with extension into the globe and filling vitreous cavity.
    Conclusion
    ONG may extend to the vitreous cavity with no simultaneous intracranial involvement.
    Keywords: Optic nerve, Glioma, Intraocular tumor
  • Giancarlo A. Garcia, Jack J. Tian, Supanut Apinyawasisuk, Sarah Kim, Handan Akil, Alfredo A. Sadun Pages 232-236
    Purpose
    We present a case of bilateral extensive peripapillary myelinated retinal nerve fibers (MRNF) in an individual with Crouzon syndrome, an inherited form of craniosynostosis caused by overactivation of fibroblast growth factor receptor 2. As a secondary aim, we examine the utility of optical coherence tomography (OCT) angiography for visualization of peripapillary vasculature obscured by myelination on other imaging modalities.
    Methods
    A 24-year-old woman with Crouzon syndrome was evaluated for suspected optic neuritis in the right eye.
    Results
    Funduscopic examination and photography revealed the incidental finding of bilateral extensive peripapillary MRNF. OCT angiography provided excellent visualization of peripapillary retinal vessels, which were partially obscured by myelination on other imaging modalities.
    Conclusions
    This association of Crouzon syndrome with bilateral peripapillary MRNF may lend insight into the developmental control of optic nerve myelination, the pathogenesis of MRNF, and the potential role of growth factors in these processes. Further, OCT angiography allowed for excellent blood vessel visualization in this case of MRNF.
    Keywords: Myelin, Myelinated retinal nerve fibers, Crouzon syndrome, Fibroblast growth factor receptor, Optical coherence tomography angiography
  • Alireza Peyman, Mohammadreza Peyman Page 237
    We read the interesting article entitled: “Stereoacuity after photorefractive keratectomy in myopia” by Zarei-Ghanavati et al.1 As we already published,2 data from stereopsis tests may need special care for analysis. By nature, the results of stereoacuity tests follow a geometrical sequence by multiplying at a ratio. For example, if we have 120 s of arc of stereoacuity in a subject and 480 in another, it means that the result at the second person is 4 times worse than the first one. This is different with measurements that follow an arithmetic sequence like ocular axial length in which a difference of length of 23 and 20 mm means the first number is the second number plus 3 mm. The functional consequence from a statistical standpoint would be that distribution of actual data of a geometrical sequence is expected to be highly skewed, although with regard to the central limit theorem, the distribution of the sample could be near normal enough to pass a normality test. 3 To work on data with geometric sequence properties, the skewness problem could easily be overcome by converting the data to the logarithm of them. A logarithm of the data with geometric sequence will be an arithmetic sequence, much easier to perform mathematical and statistical evaluation on. This phenomenon is well known and widely accepted in evaluation and analyzing the visual acuity data4 from the 19th century.
    For better statistical efficiency, we suggest to convert stereoacuity seconds of arc values to logarithm of second of arc and check the distribution plots.