Hae Ri Yum

Comparison of phaco-chop, divide-and-conquer, and stop-and-chop phaco techniques in microincision coaxial cataract surgery

Purpose To compare the outcomes of coaxial microincision cataract surgery (MICS) performed with 3 phacoemulsification techniques (phaco‐chop, divide‐and‐conquer, and stop‐and‐chop) according to cataract density. Setting Bucheon St. Mary’s Hospital, College of Medicine, Catholic University of Korea, Seoul, South Korea. Design Prospective randomized clinical trial. Methods Eyes with nuclear density from grade 2 to 4 were randomly subdivided into 3 groups (phaco‐chop, divide‐and‐conquer, and stop‐and‐chop). Intraoperative measurements included ultrasound time (UST), mean cumulative dissipated energy (CDE), and balanced salt solution use. Clinical measurements included preoperative and 1 day, 1 month, and 2 month postoperative corrected distance visual acuity, central corneal thickness, and endothelial cell count. Results Intraoperative measurements showed significantly less UST, CDE, and balanced salt solution use with the phaco‐chop technique than with the divide‐and‐conquer and stop‐and‐chop techniques in the grade 4 cataract density group (P<.05). The percentage of endothelial cell loss was significantly lower in the phaco‐chop group than in the divide‐and‐conquer and stop‐and‐chop groups in the grade 4 cataract density group 2 months after cataract surgery (P<.05). Conclusions All 3 techniques may be effective for coaxial MICS in mild and moderate cataracts. However, in eyes with hard cataract having coaxial MICS, the phaco‐chop technique can be more effective for lens removal, with less corneal endothelial damage, than the divide‐and‐conquer and stop‐and‐chop techniques. Financial Disclosure No author has a financial or proprietary interest in any material or method mentioned.

Changes in ocular factors according to depth variation and viewer age after watching a three-dimensional display.

Objective To investigate changes in ocular factors according to the binocular disparity in three-dimensional (3D) images and age after watching 3D display. Methods A total of 38 volunteers were enrolled, and they watched a 3D display with a 1° or 3° disparity for 30 min at an interval of 1 week. The near point of accommodation (NPA), near point of convergence (NPC) and tear break-up time (tBUT) of each subject were measured before and after watching the 3D display. In addition, the tear meniscus height and depth were measured using Visante optical coherence tomography and tear osmolarity was measured using TearLab osmometer. A survey of subjective symptoms was also conducted. Results NPA and NPC increased after watching the 3D display (p<0.05). NPC and NPA increased more in the 40s–50s group (ie, subjects aged in their 40s and 50s) than in the 20s–30s group (ie, subjects aged in their 20s and 30s) after watching 3D content with a 3° disparity (p<0.05). tBUT and tear meniscus height and depth decreased after watching 3D content (p<0.05). They decreased more in the 40s–50s group than in the 20s–30s group after watching 3D content with a 3° disparity (p<0.05). Recovery times of NPA and NPC were significantly greater after watching 3D content with a 3° disparity and in the 40s–50s group (p<0.05). Conclusions Watching a 3D display affects accommodation and convergence abilities and tear dynamics in a transient fashion, especially in the case of 3D images with a large binocular disparity, and in older subjects. These results provide helpful information for establishment of guidelines for 3D equipment manufacturers.

Pathogenic mitochondrial DNA mutations and associated clinical features in Korean patients with Leber's hereditary optic neuropathy.

PURPOSE To identify the spectrum of pathogenic mitochondrial DNA (mtDNA) mutations and clinical features in Korean patients with genetically confirmed Lebers hereditary optic neuropathy (LHON). METHODS The medical records of 34 unrelated, genetically confirmed LHON patients were reviewed. Total genomic DNA was isolated from the peripheral blood leukocytes of the patients with suspected LHON, and primary or secondary mtDNA mutations were identified by direct sequencing. We analyzed the visual acuity (VA), color vision, RNFL thickness, and visual field (VF) at the final visit from 20 patients who were followed-up for more than 6 months after the onset of LHON. RESULTS Among 34 patients, 21 (61.8%) had the homoplasmic primary mutation, 11 (32.4%) had the homoplasmic secondary mutation, and 2 (5.9%) had the heteroplasmic primary mutation along with the homoplasmic secondary mutation. Analysis of mtDNA sequences revealed six different types of LHON-associated mutations: two primary LHON-associated primary mutations, m.11778G>A (20 patients, 58.8%) and m.14484T>C (3 patients, 8.8%), and four secondary LHON-associated mutations, which were m.3394T>C (3 patients, 8.8%), m.3497C>T (4 patients, 11.8%), m.11696G>A (4 patients, 11.8%), and m.14502T>C (2 patients, 5.9%). Secondary mutation-carrying patients demonstrated a decreased in RNFL thickness, similar to those in primary mutation-carrying LHON patients. These patients had a higher female ratio (P = 0.019), better VA (P = 0.043) and color vision (P = 0.005), as well as better VF. CONCLUSIONS In addition to common primary LHON-associated mutations, our study identified secondary mtDNA mutations, which should be considered when evaluating patients with optic atrophy.

Retrocorneal membrane after Descemet membrane endothelial keratoplasty.

Purpose: To describe a retrocorneal membrane after Descemet membrane endothelial keratoplasty (DMEK). Methods: Case report and review of the medical literature. Results: A 73-year-old woman diagnosed with bilateral pseudophakic bullous keratopathy underwent DMEK in her left eye. Her preoperative best-spectacle-corrected visual acuity OD was 20/500 and OS was 20/500. After DMEK, graft detachment was found on the first and second postoperative days. Graft repositioning with air was performed 2 times. One month after DMEK, a membranous structure was identified behind the cornea by slit-lamp examination. The patient was applying topical levofloxacin 0.5% (Cravit; Santen, Japan) and prednisolone acetate 1% (Pred Forte; Allergan, Irvine, CA) 4 times per day. Two months after DMEK, the retrocorneal membrane disappeared, and the patients best-corrected visual acuity OS improved to 20/40. Conclusions: We report the first case of retrocorneal membrane formation after DMEK surgery.

Rathke cleft cyst presenting as unilateral progressive oculomotor nerve palsy

increased over the years. Although fairly uncommon, cricket balls have been known to cause incidences of minor ocular injuries with a good prognosis for recovery, but the potential for severe corneal lacerations, globe ruptures, and permanent vision loss still remains. Recently, the South African wicketkeeper, Mark Boucher, ended his international cricket career after suffering a lacerated sclera and irreparable vision loss during his last game. This case report highlights the need for protective eye equipment in recreational cricket. Regular eye glasses are not sufficient eye protection. The international Cricket Council has strict guidelines regarding the use of appropriate clothing and protective equipment during games, but currently no regulations are in place to ensure safety in recreational play. Continued injury surveillance, increase in awareness for the use of protective equipment during sports, and a need for further studies to investigate intervention strategies to reduce the risk to cricketers are advised. This information should be widely shared through sports-injury prevention campaigns to improve the regulations of recreational play. A letter of consent was obtained from the study participant regarding the use and publication of the study results.

Identification of a Fibrillin-1 Gene Mutation in a Monozygotic Twin Presenting with Bilateral Juvenile-onset Ectopia Lentis

Dear Editor, Ectopia lentis (EL) refers to displacement of a lens from its normal location, often when the fibrillin-rich microfibrils of the ciliary zonule are stretched. Marfan syndrome (MFS) is the most common systemic disease associated with EL [1]. MFS is an autosomal dominant connective tissue disorder with major involvement of ocular, skeletal, and cardiovascular systems [1]. The diagnosis of MFS is made on the basis of clinical and genetic criteria that are referred to as the Ghent criteria [1]. Mutations in the fibrillin-1 (FBN1) gene located on chromosome 15q12 are known to be causative for MFS [1,2,3]. The FBN1 mutations are associated with an increased risk of aortic dilatation and dissection, regardless of the clinical presentation [3]. We report a case of monozygotic twin boys presenting initially with juvenile-onset bilateral EL with disease-causing missense mutation in the FBN1 gene. Five-year-old monozygotic twin boys were referred for evaluation of low vision in both eyes. They were born at 37 weeks gestation and weighed about 2.5 kg. They were the second birth of non-consanguineous parents. There was no previous family history of ocular, systemic, or chromosomal disorders. The first-born boy had best-corrected visual acuity (BCVA) of 20 / 50 in the right eye with a refraction of +2.00 Dsph = -4.50 Dcyl × 170°A and 20 / 120 in the left eye with a refraction of +1.00 Dsph = -7.75 Dcyl × 180°A. On slit lamp examination, the lenses of the right and left eyes were upwardly and superonasally dislocated, respectively, with the left eye having more severe displacement (Fig. 1A). The second boys BCVA was 20 / 60 in the right eye with a refraction of +1.50 Dsph = -5.75 Dcyl × 10°A and 20 / 50 in the left eye with a refraction of +2.00 Dsph = -4.00 Dcyl × 10°A. The lenses were displaced superotemporally and upwardly in his right and left eyes, respectively (Fig. 1B). No other features of MFS were identified on initial examination. After obtaining informed consent from their parents, direct DNA sequencing of the FBN1 gene was performed. Direct sequencing of all exons of the FBN1 revealed a heterozygous missense mutation (c.7583G>T) in exon 62 which results in a change from cysteine to phenylalanine (Cys2528Phe) (Fig. 1C and 1D). This mutation was first reported in a French female patient with MFS but has not been previously reported in Korea [4]. It is predicted to be damaging as shown in Sorting Intolerant from Tolerant analysis (SIFT, http://sift.jcvi.org). This mutation was absent in their parents (Fig. 1C). Based on the molecular result, cardiac evaluation was recommended, and echocardiography was performed which revealed aortic root dilatation in both patients. They were prescribed a beta-blocker to prevent further enlargement of the aortic root. The amblyopia was successfully treated with spectacle correction of high astigmatism. After 1 year, the first-born boy had BCVA of 20 / 25 in the right eye and 20 / 60 in the left eye. The second boys BCVA was 20 / 40 in the right eye and 20 / 32 in the left eye. Fig. 1 (A) Images of patient 1. The lenses were displaced upwardly and superonasally in his right and left eyes, respectively. (B) Images of patient 2. The lenses were displaced superotemporally and upwardly in his right and left eyes, respectively

Concurrent presentation of corneal dystrophy and tilted disc syndrome: report of two cases.

Dear editor, Tilted disc syndrome (TDS) is a congenital optic nerve anomaly. The superotemporal optic disc is elevated and the inferonasal disc is posteriorly displaced, accompanied by an inferonasal crescent, posterior staphyloma, retinal pigment epithelium thinning, and situs inversus [1, 2]. A suspected cause of TDS is anomalous embryogenesis, especially incomplete closure of the fetal fissure at sixth weeks of gestation [3]. Corneal dystrophy associated with optic disc anomaly has been rarely reported. To our knowledge, there has been no report of corneal dystrophy with TDS in the English literature. We report two cases of granular corneal dystrophy type II (GCDII) and posterior polymorphous corneal dystrophy (PPCD) concomitant with TDS. A 45 year-old male patient visited our clinic complaining of decreased visual acuity in both eyes. He denied a history of ocular, systemic, or hereditary disease. His best-corrected visual acuity (BCVA) was 20/100 OD and 20/70 OS. Multiple anterior stromal corneal deposits with a dot, crumb, or snowflake appearance were noted to the same degree in both eyes (Fig. 1a). Fundus examination showed tilted optic discs with inferiorly located conus and situs inversus in both eyes, which was consistent with the findings of TDS (Fig. 1b). A bitemporal visual field defect was observed on Humphrey visual field examination (Fig. 1c). Sequential magnetic resonance imaging of the brain revealed no evidence of chiasmal compression. The visual field defect was attributed to TDS, and the patient was being monitored periodically. He was a heterozygote of the R124H mutation of the transforming growth factor-betainduced (TGFBI) gene, which is responsible for GCDII. An 8 year-old female patient was referred for a general ocular examination. There was no previous family history of ocular or chromosomal disorders. The BCVAwas 20/25 and the corneal diameter was 10.5 mm in both eyes. Her left eye showed a linear horizontal parallel lesion on the posterior corneal layer (Fig. 2a). Specular microscopy of her left eye revealed enlarged pleomorphic endothelial cells with welldemarcated dark areas, whereas her right eye showed normal-appearing endothelial cells (Fig. 2c). Fundus examination showed a slightly oval-shaped disc, situs inversus, and tessellated nasal side fundus in her left eye, which was comparable to the findings of unilateral TDS (Fig. 2b). Genetic analysis for collagen type VIII alpha2 (COL8A2) gene revealed c.105G>A (A35A) mutation, which was reported to be associated with Fuchs’ dystrophy [3]. The first patient had bilateral TDS with GCDII. His main problems were decreased visual acuity due to the corneal opacity associated with GCDII and the bitemporal visual field defect resulting from TDS. Usually, bilateral hemianopsia in TDS does not respect the vertical midline, as in this case, in contrast with chiasmal compression lesions, which does respect the vertical midline. In patients with bilateral TDS manifesting bitemporal visual field defects, brain neuroimaging should be necessary to differentiate between TDS and chiasmal compression [4, 5]. S. Y. Choi :H. R. Yum : S. H. Park (*) Department of Ophthalmology and Visual Science, Seoul St. Mary’s Hospital, College of Medicine, the Catholic University of Korea, 222 Banpo-daero, Seocho-gu, Seoul 137-701, Republic of Korea e-mail: vaccine@catholic.ac.kr