Won Yeol Ryu

Prediction of enophthalmos by computer-based volume measurement of orbital fractures in a Korean population.

Purpose: To estimate posttraumatic enophthalmos using computer-based volume measurement of the orbital fracture to provide information on surgical guidelines. Methods: The fracture volume of orbital wall fractures in 35 patients who did not undergo surgery was measured using a Rapidia work station system. Hertel ophthalmometry, diplopia, and ocular motility were investigated. The fracture volume measurements relative to the intact contralateral orbit were correlated with enophthalmos, diplopia, and ocular motility. Patients were examined at the initial visit, then at 1 week, 1 month, and 3 months. Results: There was a correlation between the fracture volume and enophthalmos. Late enophthalmos increased in size in proportion to the volume of the fractured site. The predicted orbital fracture volume with an enophthalmos measurement of 2 mm or more was 2.30 ml. Conclusions: Computer-based measurements of orbital fracture volume can be used to predict overall enophthalmos and provide useful information to surgeons.

Cytoplasmic and Nuclear Anti-Apoptotic Roles of αB-Crystallin in Retinal Pigment Epithelial Cells

In addition to its well-characterized role in the lens, αB-crystallin performs other functions. Methylglyoxal (MGO) can alter the function of the basement membrane of retinal pigment epithelial (RPE) cells. Thus, if MGO is not efficiently detoxified, it can induce adverse reactions in RPE cells. In this study, we examined the mechanisms underlying the anti-apoptotic activity of αB-crystallin in the human retinal pigment epithelial cell line ARPE-19 following MGO treatment using various assays, including nuclear staining, flow cytometry, DNA electrophoresis, pulse field gel electrophoresis, western blot analysis, confocal microscopy and co-immunoprecipitation assays. To directly assess the role of phosphorylation of αB-crystallin, we used site-directed mutagenesis to convert relevant serine residues to alanine residues. Using these techniques, we demonstrated that MGO induces apoptosis in ARPE-19 cells. Silencing αB-crystallin sensitized ARPE-19 cells to MGO-induced apoptosis, indicating that αB-crystallin protects ARPE-19 cells from MGO-induced apoptosis. Furthermore, we found that αB-crystallin interacts with the caspase subtypes, caspase-2L, -2S, -3, -4, -7, -8, -9 and -12 in untreated control ARPE-19 cells and that MGO treatment caused the dissociation of these caspase subtypes from αB-crystallin; transfection of S19A, S45A or S59A mutants caused the depletion of αB-crystallin from the nuclei of untreated control RPE cells leading to the release of caspase subtypes. Additionally, transfection of these mutants enhanced MGO-induced apoptosis in ARPE-19 cells, indicating that phosphorylation of nuclear αB-crystallin on serine residues 19, 45 and 59 plays a pivotal role in preventing apoptosis in ARPE-19 cells. Taken together, these results suggest that αB-crystallin prevents caspase activation by physically interacting with caspase subtypes in the cytoplasm and nucleus, thereby protecting RPE cells from MGO-induced apoptosis.

The Clinical Characteristics and Surgical Outcomes of Epiblepharon in Korean Children: A 9-Year Experience

Purpose. To examine the demographic characteristics, clinical features, surgical outcomes, and long-term prognoses of epiblepharon in Korean children. Methods. Epiblepharon patients who were followed for ≥ 6 month following surgical correction between January 2005 and December 2013. The patient demographics, clinical features, concomitant disorders, surgical outcomes, and complications were retrospectively reviewed. Results. A total of 768 epiblepharon records were included in the analysis. The mean patient age was 6.55 ± 2.37 years. At presentation, 712 patients (92.8%) complained of typical epiblepharon symptoms. The mean patient age at surgery was 6.95 ± 2.52 years, with 629 patients (81.9%) on the lower lid and 72 patients (9.4%) on the upper lid and 82 patients (10.7%) undergoing surgery on both lids. The eyelid was well everted with no recurrence in 740 patients (96.4%). Conclusion. Epiblepharon frequently occurs in Korean children and is correctable with a simple surgery. Recurrence and serious complications do not occur often, and any suspicions of epiblepharon should be investigated. A thorough ocular examination can lead to a correct diagnosis and timely corrective surgery. Most procedures are successful and prevent secondary complications that often occur with uncorrected epiblepharon.

Efficacy of temperature-sensitive Guardix-SG for adhesiolysis in experimentally induced eyelid adhesion in rabbits.

Purpose: To determine the efficacy of a temperature-sensitive poloxamer/alginate mixture (Guardix-SG) for reducing adhesions after blepharoplasty in rabbit models. Methods: Thirty-six intact eyes of 18 rabbits were randomly designated to 2 groups, and primary blepharoplasty was performed on both the upper eyelids of the 18 rabbits. Sterile cotton soaked in 1 N NaOH was used to produce chemical tissue damage to experimentally induce eyelid adhesion, which was followed by adhesiolysis in 2 weeks. During adhesiolysis, Guardix-SG was applied to the OD of rabbits in the experimental group, while adhesiolysis alone was performed on the OS of rabbits in the control group. Both sides were compared by gross examination 1 day, 1 week, and 4 weeks after surgery, and the degrees of inflammation and fibrosis were examined with hematoxylin-eosin (H&E) and Masson’s trichrome (MT) stains. The expression of &agr;-smooth muscle actin (&agr;-SMA) antibody was also immunohistochemically examined. Results: The gross examinations performed after adhesiolysis yielded results that were not significantly different between the experimental and the control groups, and no prevalent complications, such as eyelid traction or distorted eyelids, were observed. One day (p = 0.028), 1 week (p = 0.028), and 4 weeks (p = 0.028) after surgery, the experimental group had a lower infiltration rate of inflammatory cells than the control group, as shown by H&E staining. The MT staining and &agr;-SMA staining also showed that the collagen deposition and fibrosis (1 week, p = 0.059; 4 weeks, p = 0.034) and the degree of myofibroblast differentiation were significantly lower in the experimental group than in the controls (1 week, p = 0.027; 4 weeks, p = 0.024). Conclusions: The temperature-sensitive poloxamer/alginate mixture (Guardix-SG) decreased inflammation and fibrosis after blepharoplasty and histopathologically prevented the readhesion of secondary blepharoplasty in rabbit models. Therefore, additional clinical studies are needed for other ophthalmic surgeries that could benefit from preventing postoperative adhesions.

The advancement of the medial rectus muscle for consecutive exotropia.

OBJECTIVE To characterize the dose effect of the advancement of the medial rectus muscle (MR) for consecutive exotropia (XT) after corrective surgery for infantile esotropia (ET) and provide a guide for achieving orthotropia. DESIGN Retrospective cohort study. PARTICIPANTS Seventy-seven patients with consecutive XT that developed after surgery for infantile ET. METHODS All patients underwent advancement of the unilateral or bilateral MR and were followed up for at least 1 year. The angle of deviation and stereopsis were retrospectively reviewed from patient records. RESULTS At the time of surgery for infantile ET, the mean eso-angle was 52.2 ± 13.10 prism diopters (PD; mean age, 28.5 ± 16.97 months). The exo-angle of consecutive XT was 25.6 ± 8.47 PD (mean age at surgery, 132.7 ± 82.32 months). The mean deviation was 1.8 ± 10.40 PD XT at the final follow-up (47.0 ± 43.57 months). The corrective effect of the exo-angle for a 1-mm advancement of the MR was 3.1 PD at 1 year after surgery and 2.9 PD at the last follow-up. There was a significant positive relationship between the preoperative exo-angle and the corrective effect of the 1-mm advancement of the MR at the last follow-up (r = 0.367, p < 0.05). Postoperatively, orthotropia was present in 79.2% of patients, re-exodrift in 16.9%, and ET in 3.9%. Favourable stereopsis was achieved in 73.2%. CONCLUSIONS MR advancement was effective for treating consecutive XT, followed by recession of the MR for infantile ET, achieving favourable stereopsis. The corrective value was 3 PD per 1-mm advancement of the MR.

Herpes zoster ophthalmicus with isolated trochlear nerve palsy in an otherwise healthy 13-year-old girl

Herpes zoster ophthalmicus is rare in healthy children. It is occasionally associated with extraocular muscle palsies and rarely with isolated trochlear nerve palsy. We report a case of unilateral isolated trochlear nerve palsy associated with herpes zoster ophthalmicus in an immunocompetent 13-year-old girl who presented with diplopia and blurred vision in her right eye. The right cornea had multiple subepithelial opacities. Ocular motility returned to normal and diplopia and corneal opacification resolved with steroid therapy. To our knowledge, this is the first such case involving the troclear nerve in a child.

The effect of a temperature-sensitive poloxamer-alginate-CaCl2 mixture after strabismus surgery in a rabbit model

PURPOSE To determine the efficacy of a temperature-sensitive poloxamer-alginate mixture in reducing adhesions after strabismus surgery in a rabbit model. METHODS The superior rectus muscle was recessed in each of 36 eyes from 18 rabbits. One randomly assigned eye in each rabbit was treated with a poloxamer-alginate mixture (PA group); the other eye was treated with a subconjunctival injection of saline (control group). The adhesions between the superior rectus muscle, sclera, and conjunctiva were clinically evaluated by a masked observer at 1 day, 1 week, and 4 weeks after surgery. Inflammation was analyzed by hematoxylin and eosin staining and anti-CD11b staining. Late fibrosis was assessed by the Masson trichrome and α-smooth muscle actin staining. Adhesion, inflammation, and fibrosis were graded on a scale of 0-4. RESULTS There was no significant between-group difference in the degree of adhesion at 1 day and 4 weeks after surgery. However, the degree of adhesion in the PA group was lower than that in the control group at postoperative week 1 (P < 0.05). Acute inflammation was similar between the groups (P > 0.05). At postoperative week 4, inflammatory cell infiltration was reduced in the PA group (P = 0.046). A significant between-group difference in late fibrosis at postoperative week 4 was observed through the Masson trichrome (P = 0.024) and α-smooth muscle actin staining (P = 0.025). CONCLUSIONS The poloxamer-alginate mixture significantly decreased adhesion after strabismus surgery in a rabbit model. Additional studies are warranted to evaluate the use of this mixture in preventing postoperative adhesions.

The study of anatomic relationship between the müller muscle and the tarsus in asian upper eyelid.

Purpose: This study was performed to clarify the detailed anatomic relationship between the insertion of Müller muscle and the tarsus in Asian upper eyelids. Materials and Methods: Eight upper eyelids of 4 formalin-fixed Asian cadavers (4 males; age range, 48–69 years; mean age, 60.2 years) were examined. Three perpendicular dissected sections with a 2-mm thickness were obtained from each eyelid. One section was obtained from the midline, and another 2 sections were obtained, each 3-mm from the lateral and medial ends of the tarsus, respectively. Samples were stained with hematoxylin-eosin, Masson trichrome, and antismooth muscle actin antibody and examined microscopically. Results: Müller muscle did not insert directly in the tarsus. However, its muscle tissues were tapered to the superior margin of the tarsus, and the space between the Müller muscle and the tarsus was bridged by fibrous connective tissue strands. Meanwhile, according to a result that measured distance between the Müller muscle insertion and the tarsus, the insertion of Müller muscle was positioned closer in the tarsus at the midline section than at the lateral or medial sections. Conclusions: This study suggests that the Müller muscle is broadly distributed around the superior border of the tarsus as tapered, aggregated smooth muscle bundles without direct insertion on the superior border of the tarsus, despite a few limitation.

Changes in refractive error in patients with accommodative esotropia after being weaned from hyperopic correction

Background To determine the long-term changes in refractive error and ocular alignment in patients with accommodative esotropia (AET) who were able to discontinue wearing hyperopic glasses because of emmetropisation. Methods Forty-seven patients with refractive AET who achieved emmetropisation and orthotropia without hyperopic glasses and were followed up for at least 3 years were enrolled. All of the patients had been prescribed the weakest possible glasses for best corrected vision. Refractive error and ocular alignment were analysed after the cessation of hyperopic glasses use. Results The mean length of follow-up was 5.7±3.21 years after successful weaning from hyperoptic glasses. The mean spherical equivalent (SE) of the refractive error was −1.01±1.53 dioptres (D), and the mean esotropia (ET) was 1.0±8.70 Δ at the final visit. Myopia developed in 55.3% of all patients. The mean myopic progression rate per year was −0.19±0.23 D/year. Forty-one patients (87.2%) showed orthotropia; in addition, three of the patients (6.4%) developed ET, and three (6.4%) developed exotropia (XT). The six patients who had ET or XT all showed myopia. Two of the three patients who developed ET underwent surgery. Both patients initially had a low degree of hyperopia and a high ratio of accommodative convergence to accommodation (AC/A). The initial hyperopia correlated with the SE refractive error at the final follow-up (p<0.001). Conclusions When emmetropisation occurs early in patients with AET, it is necessary to note the development of myopia and the deterioration of ocular alignment.

Efficacy of Seprafilm® graft with adhesiolysis in experimentally induced lid adhesion in rabbits

AIM To evaluate the efficacy of Seprafilm(®) transplantation following adhesiolysis for preventing postoperative readhesion and improving surgical outcomes. METHODS Primary blepharoplasty was carried out on both eyelids of 18 albino rabbits. After 2 weeks, a new skin incision was made, and adhesiolysis was performed on both eyelids. The rabbits were categorized into two groups, one with adhesiolysis alone in the left eyelid (control group), and the other with adhesiolysis with a Seprafilm(®) graft in the right eyelid (Seprafilm(®) group). The degrees of inflammation and fibrosis were examined with hematoxylin-eosin (HE) and Massons trichrome stains. Expression of α-smooth muscle actin (α-SMA) was also immunohistochemically examined. RESULTS Eyelid examination immediately after the operation revealed mild swelling and hemorrhage in both groups, but these symptoms resolved after 1 week-2 weeks, and eyelid shape had recovered completely in both groups. Microscopic assessments demonstrated that the Seprafilm(®) group showed less inflammation and fibrosis than the control group. The Seprafilm(®) group also exhibited fewer α-SMA-positive cells than the control group. CONCLUSION Based on these findings, we conclude that Seprafilm(®) graft with adhesiolysis is an effective method for preventing postoperative readhesions after eyelid surgery.