Ungsoo Samuel Kim

Analysis of spectral domain optical coherence tomography findings in occult macular dystrophy

Acta Ophthalmol. 2011: 89: e52–e56

Early stage ethambutol optic neuropathy: retinal nerve fiber layer and optical coherence tomography.

Purpose To evaluate retinal nerve fiber layer (RNFL) thickness with optical coherence tomography (OCT) in early stage ethambutol optic neuropathy. Methods The RNFL thickness of 20 eyes of 10 patients who developed optic neuropathy after taking ethambutol and visited within 6 months after onset were analyzed and compared with those of 54 eyes of 29 healthy age-matched controls. The mean age was 67.40±10.25 years for the patients with toxic optic neuropathy and 66.78±10.60 for the control group (p=0.948). A full ophthalmologic examination including RNFL evaluation with fast RNFL thickness (3.4) scanning using a Stratus OCT (Carl Zeiss Meditec, Dublin, CA) was performed. Results RNFL thicknesses associated with early ethambutol optic neuropathy were as follows: temporal 75.35±15.77 μm, superior 124.05±24.62 μm, nasal 75.15±24.23 μm, inferior 127.60±22.91 μm, and the average was 100.83±16.56 μm. There was no significant difference between the RNFL thickness of the patients with the early stage of ethambutol optic neuropathy and those of the control group. The thickness of RNFL was greater in the temporal quadrant than the nasal quadrant, although not statistically significant. Conclusions RNFL thickness associated with ethambutol optic neuropathy during the early stages was not different from the controls. Although not statistically significant, the relative thickening of temporal RNFL in our patients might represent a mild swelling of the papillomacular bundle.

Analysis of the Causes of Optic Disc Swelling

Purpose To investigate the clinical manifestations and diagnoses of optic disc swelling. Methods The medical records of 49 patients who experienced optic disc swelling between March 2008 and June 2009 were retrospectively reviewed. The characteristics of non-arteritic anterior ischemic optic neuropathy (NA-AION) and optic neuritis (ON), which showed optic disc swelling most commonly, were compared. Results NA-AION was the most common disorder (34.7%) that presented with optic disc swelling. ON was identified in 15 patients (30.6%). Seven out of 49 patients (14.3%) had intracranially associated diseases, such as papilledema and compressive optic neuropathy. Pseudopapilledema was noted in four patients (8.2%). Other diseases (e.g., papillophlebitis, neuroretinitis, and diabetic papillopathy) were seen in six patients (12.2%). Ocular pain was observed more commonly in patients with ON (p = 0.001). Patients with ON expected a better visual prognosis than patients with NA-AION (0.12 ± 0.32 vs. 0.49 ± 0.35, p = 0.001). Conclusions NA-AION and ON should be considered in the differential diagnosis when patients with optic disc swelling present to the neuro-ophthalmology clinic. Detailed history taking and supportive examinations, such as visual field, color-vision and imaging tests, should also be performed as indicated. Regular follow-up of such exams is necessary for the differential diagnosis of these diseases.

The Correlation between Angle Kappa and Ocular Biometry in Koreans

Purpose To investigate normative angle kappa data and to examine whether correlations exist between angle kappa and ocular biometric measurements (e.g., refractive error, axial length) and demographic features in Koreans. Methods Data from 436 eyes (213 males and 223 females) were analyzed in this study. The angle kappa was measured using Orbscan II. We used ocular biometric measurements, including refractive spherical equivalent, interpupillary distance and axial length, to investigate the correlations between angle kappa and ocular biometry. The IOL Master ver. 5.02 was used to obtain axial length. Results The mean patient age was 57.5 ± 12.0 years in males and 59.4 ± 12.4 years in females (p = 0.11). Angle kappa averaged 4.70 ± 2.70 degrees in men and 4.89 ± 2.14 degrees in women (p = 0.48). Axial length and spherical equivalent were correlated with angle kappa (r = -0.342 and r = 0.197, respectively). The correlation between axial length and spherical equivalent had a negative correlation (r = -0.540, p < 0.001). Conclusions Angle kappa increased with spherical equivalent and age. Thus, careful manipulation should be considered in older and hyperopic patients when planning refractive or strabismus surgery.

One sister and brother with mirror image myopic anisometropia.

We report a case of one sister and brother with mirror image myopic anisometropia. One sister and brother complained visual disturbance. The sister was 10 years 11 months old, and brother was 8 years 4 months old. Full ophthalmic examinations were performed, including slit lamp examination, intraocular pressure, keratometry, anterior chamber depth, axial length, fundus examination and the cycloplegic refraction. The cycloplegic refractive power was -15.50 dpt cyl.+4.50 dpt Ax 85° (right eye), -1.00 dpt cyl.+0.50 dpt Ax 90° (left eye) in the sister; -1.75 dpt cyl.+2.25 dpt Ax 90° (right eye), -9.50 dpt cyl.+4.00 dpt Ax 80° (left eye) in the brother. The co-occurrence of severe myopic anisometropia in a sister and brother is extremely rare. The present case suggests that severe myopic anisometropia may be related by genetic inheritance.

A Case of Myotonic Dystrophy With Pigmentary Retinal Changes

A 46-year-old man presented with visual disturbances in both eyes. His best corrected visual acuity was 0.7 (both eyes). Ptosis and limitation of ocular movement in every direction were observed. Slit lamp examination showed a bilateral iridescent cataract. Fundus examination showed peripheral depigmentation of the retinal pigment epithelium and pigmentary clumping in both eyes that agreed with blocked fluorescence and widow defects on fluorescein angiography. The amplitude of b-wave was decreased on electroretinography. Fourteen months later, the patients best corrected visual acuity decreased to 0.3 due to increased lens opacity. Phacoemulsification and intraocular lens implantation were performed on both eyes. At the patients final visit, retinal findings were stable with a best corrected visual acuity of 0.7 in both eyes. In conclusion, the visual disturbance could have been caused by both cataracts and retinal degeneration, meaning the fundus should be examined carefully in patients with myotonic dystrophy.

Spectral domain optical coherence tomography findings in bilateral peripheral cone dystrophy

IntroductionTo report spectral domain optical coherence (OCT) tomography findings in a case of bilateral peripheral cone dystrophy.Case ReportA 21-year-old man complained of blurred visual fields on the lateral sides of both eyes. The patient’s best-corrected visual acuity was 20/20 in both eyes. Fundus examination revealed mild temporal pallor, while fluorescein angiography did not show any abnormalities. Humphrey’s visual field revealed a C-shaped scotoma. Photopic electroretinogram (ERG) and 30-Hz flicker revealed decreased cone function; however, scotopic ERG noted a normal response. Multifocal ERG revealed a relatively well-preserved macular area but with reduced amplitude in the peripheral areas of both eyes. On OCT, the photoreceptor inner and outer segment junction and retinal pigment epithelium (RPE) layers were well preserved in both eyes, except for a slight decrease in outer layer thickness. Moreover, on the macular thickness map obtained from Cirrus HD-OCT, a reduction in internal limiting membrane-RPE thickness that correlated well with visual field defects was revealed in both eyes. On the retinal nerve fiber layer (RNFL) thickness map obtained from Cirrus HD-OCT, the superior quadrant showed decreased RNFL thickness; however, thickness in the temporal quadrant corresponded with thickness in the macular area and was normal in both eyes.DiscussionThe OCT of a patient with peripheral cone dystrophy revealed decreased thickness of the macula with well-preserved retinal structures, which may be one of the distinctive features of this condition.

Attempts to Reduce the Progression of Myopia and Spectacle Prescriptions during Childhood: A Survey of Eye Specialists

Purpose To determine methods tried in clinical trials to reduce the progression of myopia in children, and spectacle prescribing patterns of hospital ophthalmologists. Methods A multi-sectioned survey composed of Likert items relating to the methods of reducing myopia progression (orthokeratology lenses [O-K lenses], undercorrected glasses, and topical atropine) and the patterns of prescribing spectacles for children (including two cases involving a 5-year-old girl and an 8-year-old boy) were distributed to members of the Korean Ophthalmological Society, and the collected data was statistically analyzed. Results A total of 78 out of 130 ophthalmologists returned the survey. On a scale of 1 to 5, the mean rates of whether the ophthalmologists think O-K lenses arrest myopia progression, and whether they recommend their patients to wear O-K lenses if indicative, were 3.06 and 2.75, respectively. Moreover, the mean rates of whether they consider that wearing glasses which are undercorrected would slow down the progression of the myopia, or if they think topical atropine helps in arresting myopia progression in children, were 2.34 and 1.27, respectively. In response to the case studies, the majority of practitioners preferred to prescribe the full amount found in cycloplegic refraction to pediatric patients with myopia. Conclusions Ophthalmologists in clinical practice encouraged children to wear O-K lenses more than undercorrected glasses as a way to retard myopia progression. However, the application of atropine is rarely tried in clinical trials. In managing pediatric patients with myopia (case specific), the majority of the practitioners chose to prescribe glasses with full cycloplegic correction.

Using ImageJ to evaluate optic disc pallor in traumatic optic neuropathy.

Purpose To evaluate optic disc pallor using ImageJ in traumatic optic neuropathy (TON). Methods This study examined unilateral TON patients. The optic disc was divided into 4 quadrants (temporal, superior, nasal, and inferior), consistent with the quadrants on optical coherence tomography (OCT) retinal nerve fiber layer (RNFL) thickness maps. Optic disc photography was performed and disc pallor was quantified using gray scale photographic images imported into ImageJ software. The correlation between optic disc pallor and RNFL thickness was examined in each quadrant. Results A total of 35 patients (31 male, 4 female) were enrolled in the study. The mean participant age was 34.8 ± 15.0 years (range, 5 to 63 years). Overall RNFL thickness decreased in 6 patients, with thinning most often occurring in the inferior quadrant (28 of 35 eyes). There was a significant correlation between optic disc pallor and RNFL thickness (superior, rho = -0.358, p = 0.04; inferior, rho = -0.345, p = 0.04; nasal, rho = -0.417, p = 0.01; temporal, rho = -0.390, p = 0.02). The highest level of correspondence between disc pallor and RNFL thickness values outside of the normative 95th percentiles was 39.3% and occurred in the inferior quadrant. Conclusions Optic disc pallor in TON was quantified with ImageJ and was significantly correlated with RNFL thickness abnormalities. Thus, ImageJ evaluations of disc pallor may be useful for evaluating RNFL thinning, as verified by OCT RNFL analyses.

Maculopathy Associated with Tacrolimus (FK 506)

A 63-year-old man with a history of liver transplantation presented to our clinic complaining of visual disturbance. He had been receiving tacrolimus (FK 506) for 30 months (6 mg/day for 2 years and 3 mg/day for 6 months); he reported that the visual disturbance began while taking tacrolimus. A full ophthalmologic examination and electrophysiologic and imaging studies were performed. The best corrected visual acuity was 0.1 in both eyes. There were no abnormal finding in the anterior segment, pupillary reflexes were normal and, there was no swelling in either optic disc. Although the foveal reflex was slightly decreased, fluorescein angiography revealed non-specific signs, with the exception of a window defect. A multifocal electro-retinogram revealed decreased amplitude of the central ring. A Swedish interactive threshold algorithm-standard 10-2 visual field test revealed a central scotoma. These findings suggest that tacrolimus may result in maculopathy. Therefore, careful ophthalmologic examination is necessary in the patients taking tacrolimus.