Jaemoon Ahn

Ocular perfusion pressure and choroidal thickness in early age-related macular degeneration patients with reticular pseudodrusen

Purpose The purpose of this study was to investigate the relationship between the ocular perfusion pressure (OPP) and subfoveal choroidal thickness (CT) in eyes with early age-related macular degeneration (AMD) with or without reticular pseudodrusen (RPD). Methods We evaluated the clinical history, blood pressure parameters, fundus photography, and optical coherence tomography images of consecutive patients with early AMD. We calculated the mean OPP from blood pressure and intraocular pressure. Results We included 103 eyes from 103 patients, classifying 45 as the RPD group and 58 as the non-RPD group. The mean OPP of the RPD group (46.1 ± 6.5 mm Hg) did not differ from that of the non-RPD group (45.1 ± 5.1 mm Hg, P = 0.325), but the RPD group showed a thinner mean subfoveal CT (158.3 ± 73.0 μm) than the non-RPD group (220.9 ± 67.0 μm, P < 0.001). Among 64 patients who underwent follow-up examination, the rate of change in subfoveal CT in the RPD group (-4.74 ± 0.86 μm/y) was greater than that in the non-RPD group (-2.46 ± 0.75 μm/y, P = 0.028). In the RPD group, a history of systemic hypertension and lower baseline OPP were associated with a higher rate of change in subfoveal CT (P = 0.019 and P = 0.010, respectively). Conclusions Subfoveal CT was thinner in early AMD patients with RPD than in those without RPD. Lower baseline mean OPP and a history of systemic hypertension could be risk factors associated with the progression of choroidal thinning in early AMD patients with RPD.

Effects of a high level of illumination before sleep at night on chorioretinal thickness and ocular biometry

ABSTRACT The choroid is affected by many factors. One of the factors, change in illumination has been suggested to influence choroidal thickness. However, the effects of bright light before sleep at night on the human eye are not well established. The purpose of this study was to investigate the effects of a high level of illumination in the evening on ocular measurements. Twenty‐seven men with myopia spent seven consecutive nights in the sleep laboratory. During the first two nights, subjects were exposed to light at 150 lux between 20:00 and midnight. Then, for five consecutive nights, they were exposed to ambient light at 1000 lux between 20:00 and midnight. Ocular parameters and their diurnal variations were compared between the two periods and the effects of a high level of illumination were analyzed. After subjects were exposed to 1000 lux of illumination, axial length increased with borderline significance (p = 0.064). Macular volume and retinal thickness did not change. However, subfoveal choroidal thickness after exposure to 1000 lux of illumination (245.37 ± 52.84 &mgr;m) was significantly lower than that after 150 lux of illumination (268.00 ± 57.10 &mgr;m), (p < 0.001). Significant diurnal variations were found in mean keratometry (p = 0.039), intraocular pressure (IOP, p = 0.003), ocular perfusion pressure (OPP, p < 0.0001), macular volume (p = 0.019), and subfoveal choroidal thickness (p < 0.0001). A high level of illumination had significant effects on only IOP and OPP (p = 0.027 and 0.017, respectively). Bright light exposure before sleep at an intensity as high as 1000 lux reduced subfoveal choroidal thickness in healthy young men. In conclusion, diurnal variation in choroidal thickness can be affected by bright light exposure before sleep. HighlightsAfter bright light exposure, axial length was increased and choroidal thickness was decreased.Choroidal thickness has diurnal variation.Diurnal variation of choroidal thickness has no change after bright light exposure.

The use of a 20-gauge valved cannula during pars plana phacofragmentation with a 23-gauge ultrasonic fragmatome.

BACKGROUND AND OBJECTIVE To evaluate the usefulness of a 20-gauge cannula to maintain a self-sealing sclerotomy wound after 23-gauge phacofragmentation. PATIENTS AND METHODS This retrospective study compared the suture rates after 23-gauge phacofragmentation when the 23-gauge cannula was temporarily replaced with a 20-gauge valved metal cannula versus when the 23-gauge fragmatome was inserted at the sclerotomy site without a cannula. RESULTS Whereas a sclerotomy was sutured in all 31 eyes in the without-cannula group, only one eye of 14 in the cannula group required a sclerotomy suture (P < .0001). However, there was one case of fragmatome tip fracture during fragmentation in the cannula group. CONCLUSION A self-sealing sclerotomy wound can be maintained without suturing by using a 20-gauge metal cannula, but fragmatome tip fracture can occur during fragmentation.

Risk factors of recurrence of macular oedema associated with branch retinal vein occlusion after intravitreal bevacizumab injection

Background/aims To identify risk factors of recurrence of macular oedema in branch retinal vein occlusion (BRVO) after intravitreal bevacizumab (IVB) injection. Methods The records of 63 patients who underwent IVB injection for macular oedema secondary to BRVO with at least 6 months of follow-up were reviewed. Patients were evaluated at baseline with fluorescein angiography (FA), optical coherence tomography (OCT) and ultra-wide-field fundus photography (WFP). During follow-up, OCT and WFP were repeated. The area of retinal haemorrhage, central retinal thickness (CRT), area (mm2) of capillary non-perfusion within the 1 mm (NPA1), 1–3 mm and 6 mm zones of the ETDRS circle, foveal capillary filling time, degree (°) of foveal capillary network destruction and FA pattern were analysed. Results Macular oedema recurred in 41 of 63 (65.1%) eyes after initial IVB injection. A binary logistic regression model showed that NPA1 (OR=434.97; 95% CI=5.52 to 34262.12, p=0.006) and initial CRT (OR=1.004; 95% CI=1.000 to 1.008, p=0.015) were significantly associated with the recurrence of macular oedema. Receiver operating characteristic curve analysis identified an NPA1 of 0.36 mm2 (AUC: 0.735, sensitivity: 70.7%; specificity: 63.6%) and an initial CRT of 570 µm (AUC: 0.745, sensitivity: 63.4%; specificity: 77.3%) as cut-off values for predicting recurrence of macular oedema. Conclusions Patients with BRVO with non-perfusion of more than half of the 1 mm zone of the ETDRS circle or with an initial CRT >570 µm should be closely monitored for macular oedema recurrence within 6 months of IVB injection.

Infective Endocarditis Presenting as Endogenous Endophthalmitis Secondary to Streptococcus agalactiae in a Healthy Adult: Case Report and Literature Review

Endogenous endophthalmitis secondary to group B Streptococcus (GBS) is extremely rare, particularly in healthy adults. However, the visual prognosis is poor. We report the first South Korean case of GBS infective endocarditis presenting as endogenous endophthalmitis and skin and soft tissue infection. Cultures of blood, vitreous humor, and pus from skin aspirates yielded a penicillin-susceptible serotype V strain of Streptococcus agalactiae. After 6 weeks, the patient completely recovered from GBS infective endocarditis. However, despite early antibiotic treatment and early surgical intervention, the patients right eye developed phthisis bulbi and was a candidate for evisceration.

Visual Discomfort While Viewing Three-dimensional Television as a Screening Tool for Pediatric Eye Diseases in Children

ABSTRACT Purpose: To investigate the efficacy of evaluating 3D asthenopia and 3D perception difficulty for screening of binocular vision abnormalities in children. Methods: Patients aged 6–12 years with abnormal binocularity, including strabismus, amblyopia, and anisometropia, were included. Age-matched normal subjects without any ophthalmologic abnormality other than a refractive error were also recruited. The best-corrected visual acuity, refractive error, angle of strabismus, and stereopsis were measured. Presenting visual acuity (PVA) was measured as the uncorrected visual acuity for subjects without glasses and spectacle-corrected visual acuity for those with glasses. After watching 3D TV for 30 min, a survey was administered to evaluate the 3D perception and 3D asthenopia. Receiver operation characteristic (ROC) curve analysis was conducted to evaluate the efficacy of the survey for detecting abnormal binocularity and poor PVA. Results: One hundred subjects were enrolled in this study. Among them, 59 had abnormal binocularity (strabismus, anisometropia, or amblyopia), and 41 were normal control. Among the entire subjects, the number of subjects with a PVA of 20/40 or worse in one or both eyes was 24 (7 from the normal control and 17 with abnormal binocularity). ROC curve analysis revealed that the survey did not effectively detect strabismus, anisometropia, or amblyopia. However, for detection of PVA 20/40 or worse in the subjects with abnormal binocularity, the total score of the survey yielded an area of 0.714 under the ROC curve (p = 0.010). The sensitivity was 88.2% and specificity was 61.9% with a cutoff at 0.50. Conclusion: The degree of 3D asthenopia and 3D perception while watching 3D TV were not effective for screening of abnormal binocularity. However, evaluation of the severity of 3D asthenopia and the quality of 3D perception can help screen of decrease in PVA that requires correction.

Relationship between cantho-limbal distance and degree of head turn in a Korean population

OBJECTIVE To evaluate the relationship between cantho-limbal distance and the degree of head turn in Koreans. DESIGN Prospective cross-sectional study. PARTICIPANTS Thirty patients without strabismus or nystagmus who had visited an ophthalmic clinic at a single medical center were included in the study. METHODS The distance between the lateral canthus and lateral corneal limbus was measured using a 5 mm scale. The degree of head turn was measured with a goniometer when the cantho-limbal distances were 0, 5, and 10 mm. The degree of head turn was measured 3 times, and the mean value was used as the degree of head turn. RESULTS When the cantho-limbal distances were 0, 5, and 10 mm, the degree of head turn values were 42.33, 30.47, and 2.53 degrees, respectively. The shorter the cantho-limbal distance, the higher the degree of head turn (r = -0.945, p < 0.01). The relationship was expressed as: Degree of head turn = -2.98 × cantho-limbal distance + 35.07. CONCLUSIONS Cantho-limbal distance can be used to estimate the degree of head turn. This method may be simpler and easier in a clinical situation than checking the degree of head turn with a goniometer.