Se Joon Woo

Optic Disc Change with Incipient Myopia of Childhood

PURPOSE To describe progressive tilting of the optic nerve head (ONH) and development/enlargement of parapapillary atrophy (PPA) observed in children with incipient myopia and to investigate factors associated with such changes. DESIGN Retrospective, observational study. PARTICIPANTS This study included 118 eyes of 118 Korean children who were assessed by serial disc photography at intervals of 1 year or more. METHODS All disc photographs were reviewed by 2 experienced ophthalmologists, and eyes were classified into 2 groups with respect to the change in the ONH appearance and development/enlargement of β-zone PPA: (1) ONH/PPA changed group and (2) ONH/PPA unchanged group. To quantify the ONH/PPA changes, the ratio of the horizontal to vertical disc diameter (HVDR) and the ratio of the maximum PPA width to vertical disc diameter (PVDR) were measured. Factors associated with ONH/PPA changes were evaluated using logistic regression analysis. Refractive errors were measured with cycloplegic refraction. MAIN OUTCOME MEASURES Morphologic changes of the ONH/PPA as observed in serial disc photographs and its association with myopic shift. RESULTS Mean subject age and refractive error at the time of initial fundus examination were 7.3 ± 3.7 years (range, 1-17 years) and -0.9 ± 1.9 diopters (range, -5.9 to +3.0 diopters), respectively. Mean follow-up period was 38.1 ± 19.6 months (range, 12-88 months). Fifty-one eyes (43%) were classified as the ONH/PPA change group. In the ONH/PPA change group, HVDR decreased from the initial value of 0.92 ± 0.08 to the final value of 0.86 ± 0.11, and the PVDR increased from the initial value of 0.08 ± 0.07 to the final value of 0.20 ± 0.11. The ONH/PPA changes were most remarkable in subjects between 7 and 9 years of age (odds ratio [OR] = 6.698; 95% confidence interval [CI], 2.296-19.546) and were associated with greater myopic shift during the follow-up period (OR = 0.483; 95% CI, 0.345-0.676). CONCLUSIONS We demonstrate progressive tilting of the ONH, which was observed with development/enlargement of PPA in children who exhibited myopic shift. These findings suggest that tilted disc, as well as PPA, may be an acquired feature in myopic eyes, arising from scleral stretching. FINANCIAL DISCLOSURE(S) The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Risk factors associated with sclerotomy leakage and postoperative hypotony after 23-gauge transconjunctival sutureless vitrectomy.

Purpose: To investigate the incidence and risk factors of sclertomy leakage and postoperative hypotony after 23-gauge transconjunctival sutureless vitrectomy. Methods: This was a retrospective study including 322 eyes of 292 patients who underwent 23-gauge transconjunctival sutureless vitrectomy by a single surgeon with minimum follow-up period of 1 month. The incidence and risk factors of intraoperative suture placement for leaking sclerotomies and postoperative hypotony (≤5 mmHg) were analyzed in association with seven clinical factors. Results: Intraoperative suture placement was required for leaking sclerotomies in 36 cases (11.2%) and was related to prior vitrectomy (OR = 7.5), young age (<50 years) at operation (OR = 4.9), and vitreous base dissection (OR = 3.5). The incidences of postoperative hypotony were 11.3% at 2 hours, 6.5% at 5 hours, 3.8% at 1 day, and 0% at 1 week. Myopia and gas tamponade were associated with early postoperative hypotony. No complications developed related to sclerotomy leakage or postoperative hypotony. Conclusions: The risk factors of intraoperative sclerotomy leakage requiring suture placement after 23-gauge transconjunctival sutureless vitrectomy are prior vitrectomy, a young age at operation, and vitreous base dissection. Caution should be exercised to ensure the detection of sclerotomy leakage and hypotony in cases with these risk factors.

Differentiation of Optic Nerve Head Drusen and Optic Disc Edema with Spectral-Domain Optical Coherence Tomography

PURPOSE To evaluate the efficacy of spectral-domain optical coherence tomography (SD-OCT) in differentiating optic disc edema (ODE) and optic nerve head drusen (ONHD) and to reveal the differential points. DESIGN Comparative case series. PARTICIPANTS Forty-five patients with ONHD, 15 patients with ODE, and 32 normal controls. METHODS Spectral-domain optical coherence tomography was performed with scans on the optic nerve head and measurements of retinal nerve fiber layer thickness. MAIN OUTCOME MEASURES Qualitative findings of optic nerve head scans and retinal nerve fiber layer thickness profiles on SD-OCT. RESULTS Optic nerve head drusen was visualized as a focal, hyperreflective, subretinal mass with a discrete margin on SD-OCT. The retinal nerve fiber layer was deformed and showed pseudoedema and high reflectance. The outer nuclear layer smoothly covered the drusen, which led to a hyporeflective, boot-shaped area adjacent to the drusen. In ODE, peripapillary retinal nerve fiber layers were significantly thicker in all sections than ONHD (average thickness of ODE: 174.1±53.5 μm vs ONHD: 119.2±20.2 μm vs control: 103.4±19.1 μm, P<0.001). Retinal nerve fiber thickness in the nasal section provides a good differential marker for ODE from ONHD (area under receiver operating characteristic curve = 0.866). CONCLUSIONS With the use of SD-OCT, noninvasive and accurate differentiation of ONHD and ODE is possible.

Comparison of efficacy and safety between half-fluence and full-fluence photodynamic therapy for chronic central serous chorioretinopathy.

Purpose: To compare the efficacy and safety of half-fluence photodynamic therapy (PDT) and conventional PDT in chronic central serous chorioretinopathy. Methods: A multicenter retrospective comparison study. Retrospective review of 60 patients including 29 patients (34 eyes) who received half-fluence PDT and 31 patients (33 eyes) who received conventional PDT for the treatment of chronic central serous chorioretinopathy. Best-corrected visual acuity, central fovea retinal thickness and resolution of subretinal fluid on optical coherence tomography, and choroidal perfusion decrease on indocyanine green angiography were assessed. Choriocapillaris perfusion decrease was quantified as mean gray value ratio of treated and nontreated areas using commercial imaging software. Results: Treatment success without recurrence was achieved in 32 of 34 eyes (94.1%) treated with half-fluence PDT and 33 of 33 eyes (100%) treated with conventional PDT (P = 0.493). There was no difference in final best-corrected visual acuity (logarithm of the minimal angle of resolution) between the 2 groups (0.17 ± 0.32 vs. 0.21 ± 0.39; P = 0.603). Choriocapillaris perfusion decrease quantified from post-PDT indocyanine green angiography was significantly more severe in the conventional PDT group (P = 0.006), and it showed a positive correlation with retinal thinning after PDT (R2 = 0.380; P < 0.001). Conclusion: Half-fluence PDT is as effective as conventional PDT, while minimizing the deleterious effect on choriocapillaris perfusion and retinal thickness.

Iatrogenic Occlusion of the Ophthalmic Artery After Cosmetic Facial Filler Injections A National Survey by the Korean Retina Society

IMPORTANCE Iatrogenic occlusion of the ophthalmic artery and its branches is a rare but devastating complication of cosmetic facial filler injections. OBJECTIVE To investigate clinical and angiographic features of iatrogenic occlusion of the ophthalmic artery and its branches caused by cosmetic facial filler injections. DESIGN, SETTING, AND PARTICIPANTS Data from 44 patients with occlusion of the ophthalmic artery and its branches after cosmetic facial filler injections were obtained retrospectively from a national survey completed by members of the Korean Retina Society from 27 retinal centers. Clinical features were compared between patients grouped by angiographic findings and injected filler material. MAIN OUTCOMES AND MEASURES Visual prognosis and its relationship to angiographic findings and injected filler material. RESULTS Ophthalmic artery occlusion was classified into 6 types according to angiographic findings. Twenty-eight patients had diffuse retinal and choroidal artery occlusions (ophthalmic artery occlusion, generalized posterior ciliary artery occlusion, and central retinal artery occlusion). Sixteen patients had localized occlusions (localized posterior ciliary artery occlusion, branch retinal artery occlusion, and posterior ischemic optic neuropathy). Patients with diffuse occlusions showed worse initial and final visual acuity and less visual gain compared with those having localized occlusions. Patients receiving autologous fat injections (n = 22) had diffuse ophthalmic artery occlusions, worse visual prognosis, and a higher incidence of combined brain infarction compared with patients having hyaluronic acid injections (n = 13). CONCLUSIONS AND RELEVANCE Clinical features of iatrogenic occlusion of the ophthalmic artery and its branches following cosmetic facial filler injections were diverse according to the location and extent of obstruction and the injected filler material. Autologous fat injections were associated with a worse visual prognosis and a higher incidence of combined cerebral infarction. Extreme caution and care should be taken during these injections, and physicians should be aware of a diverse spectrum of complications following cosmetic facial filler injections.

The movement of self-assembled amphiphilic polymeric nanoparticles in the vitreous and retina after intravitreal injection

The purpose of this study is to determine the correlation between the distribution of nanoparticles in the vitreous and retina and their surface properties after intravitreal injection. For this purpose, we synthesized seven kinds of nanoparticles through self-assembly of amphiphilic polymer conjugates in aqueous condition. They showed similar size but different surface properties. They were labeled with fluorescent dyes for efficient tracking. After intravitreal injection of these nanoparticles into a rodent eye, their time-dependent distribution in the vitreous and retina was determined in stacking tissue images by confocal microscopy. The results demonstrated that the surface property of nanoparticles is a key factor in determining their distribution in the vitreous and retina after intravitreal injection. In addition, immunohistochemistry and TEM images of retina tissues suggested the important mechanism related with Mülller cells for intravitreally administered nanoparticles to overcome the physical barrier of inner limiting membrane and to penetrate into the deeper retinal structures. Therefore, we expect that this study can provide valuable information for biomedical researchers to develop optimized nanoparticles as drug or gene carriers for retinal and optic nerve disorders such as glaucoma, age-related macular degeneration, and diabetic retinopathy.

A suprachoroidal electrical retinal stimulator design for long-term animal experiments and in vivo assessment of its feasibility and biocompatibility in rabbits.

This article reports on a retinal stimulation system for long-term use in animal electrical stimulation experiments. The presented system consisted of an implantable stimulator which provided continuous electrical stimulation, and an external component which provided preset stimulation patterns and power to the implanted stimulator via a paired radio frequency (RF) coil. A rechargeable internal battery and a parameter memory component were introduced to the implanted retinal stimulator. As a result, the external component was not necessary during the stimulation mode. The inductive coil pair was used to pass the parameter data and to recharge the battery. A switch circuit was used to separate the stimulation mode from the battery recharging mode. The implantable stimulator was implemented with IC chips and the electronics, except for the stimulation electrodes, were hermetically packaged in a biocompatible metal case. A polyimide-based gold electrode array was used. Surgical implantation into rabbits was performed to verify the functionality and safety of this newly designed system. The electrodes were implanted in the suprachoroidal space. Evoked cortical potentials were recorded during electrical stimulation of the retina. Long-term follow-up using OCT showed no chorioretinal abnormality after implantation of the electrodes.

Association between Depression and Dry Eye Disease in an Elderly Population

PURPOSE A population-based cross-sectional study to investigate the association between depression and dry eye disease (DED) in a community-dwelling elderly population. METHODS The subjects were 657 Korean elders ≥ 65 years of age randomly selected from an official household registration database in Yongin, Korea. DED symptoms were assessed using the six-item Dry Eye Questionnaire. DED signs were evaluated using the Schirmer test, fluorescein stain score, tear film break-up time (BUT). Depression was assessed using the Korean version of the Short Geriatric Depression Scale (SGDS-K). The association between DED and depression was evaluated using logistic linear analyses. RESULTS The SGDS-K score correlated with the number of positive responses in the Dry Eye Questionnaire (r = 0.229, P < 0.001), but not with tear film break-up time (r = 0.041, P = 0.139) or Schirmer test score (r = 0.048, P = 0.642). In the binary logistic regression model, female sex (P = 0.014), residence in urban areas (P < 0.001), depression (P < 0.001), and Schirmer score of ≤ 5 mm (P = 0.035) were associated with the risk of DED. Depression was associated with the risk of DED (P < 0.001) in the patients with Schirmer score > 5 mm but not in those with Schirmer score ≤ 5 mm (P = 0.290). CONCLUSIONS Depression was associated with DED symptoms in subjects with normal or mildly reduced tear production.

Long-term Temporal Changes of Macular Thickness and Visual Outcome after Vitrectomy for Idiopathic Epiretinal Membrane

PURPOSE To evaluate the long-term correlation of visual outcome and macular thickness after vitrectomy for idiopathic epiretinal membrane and to identify prognostic factors for good visual outcome. DESIGN Retrospective, observational case series. METHODS We reviewed the records of 52 patients with idiopathic epiretinal membrane who were treated with vitrectomy and could be followed up for more than 12 months. The main outcome measures were best-corrected visual acuity (BCVA) and central macular thickness at baseline; at 1, 3, 6, and 12 months after surgery; and at the final follow-up visit. The correlation between BCVA and central macular thickness was analyzed and the receiver operating characteristic curve analysis was performed to obtain cutoff values for visual prognosis. RESULTS Most of the changes in BCVA and central macular thickness took place during the first 3 months and reached a plateau at 12 months after surgery. Despite the lack of changes in BCVA after 12 months of follow-up, significant reduction in central macular thickness could still be observed over 12 months after surgery. The final BCVA was correlated significantly with preoperative BCVA and central macular thickness and early postoperative central macular thickness. Among them, the postoperative central macular thickness at 1 month showed the largest area under the receiver operating characteristic curve. CONCLUSIONS Given the removal of the confounding effect of cataract, postoperative follow-up of 12 months may be sufficient to reach the final BCVA after surgery. However, more time is needed to achieve final central macular thickness. Because of the significant correlation between final BCVA and early postoperative central macular thickness, serial optical coherence tomography images in the early postoperative period were needed to predict visual outcome after epiretinal membrane removal.

Morphologic photoreceptor abnormality in occult macular dystrophy on spectral-domain optical coherence tomography.

PURPOSE. To investigate morphologic photoreceptor layer abnormalities and their correlation with visual function in occult macular dystrophy (OMD), by using spectral-domain optical coherence tomography (SD-OCT). METHODS. This observational case series included 18 eyes of 9 patients with OMD. All patients underwent an ophthalmic evaluation, which included a fundus examination, fluorescein angiography, full-field electroretinography (ERG), multifocal ERG, time-domain optical coherence tomography (TD-OCT), and visual field testing. Morphologic photoreceptor layer abnormalities of the retinal layers were investigated with SD-OCT. The structure-function relationship was investigated regarding visual acuity, symptom duration, and multifocal ERG RESULTS: RESULTS. Best corrected visual acuity ranged from 20/200 to 20/20. Four patients had a symmetric decline of acuity in both eyes (20/200-20/100), and five had unilateral vision impairment (20/200-20/50). TD-OCT showed foveal thinning in all patients, but revealed no other retinal layer abnormality. In 15 eyes of 8 patients, SD-OCT demonstrated a well-defined disruption of the inner segment-outer segment (IS-OS) junction of the photoreceptors and of the Verhoeff membrane (cone outer segment tips). SD-OCT showed that three of five patients with presumed unilateral OMD had bilateral OMD after initial or follow-up examinations. Degrees of abnormality in the photoreceptor layer varied and correlated with visual acuity and symptom duration. CONCLUSIONS. SD-OCT can demonstrate the disruption of photoreceptors in most patients with OMD and the morphologic changes on SD-OCT correlate with visual function and disease progression. These morphologic abnormalities can be an important feature and cause of vision loss in patients with OMD.