Report of Bilateral Acute Angle-closure Crisis Induced by Serotonin-norepinephrine Reuptake Inhibitors

PURPOSE@#This study reports a case of bilateral acute angle-closure crisis induced by two kinds of serotonin-norepinephrine reuptake inhibitors (SNRIs), duloxetine and tramadol.CASE SUMMARY: A 55-year-old female visited our clinic, complaining of bilateral visual impairment, ocular pain, and headache, which began 2 days after taking several drugs including duloxetine and tramadol for the purpose of back pain relief. On the day of the first visit, her uncorrected visual acuity was 0.04 in the right eye and 0.02 in the left eye, and the intraocular pressure (IOP) was 45 mmHg in the right eye and 51 mmHg in the left eye. The anterior chamber was shallow and the anterior chamber-angle was closed in both eyes on gonioscopy. There was mild nuclear sclerosis of both lenses. Assuming drug-induced bilateral acute angle-closure crisis, all medications were discontinued, and IOP-lowering agents were prescribed. The symptoms, visual acuity, and IOP improved; however, both anterior chambers were still shallow and the iridocorneal angle was still closed in both eyes. Laser iridotomy was tried in the right eye but failed because the pupils were not completely constricted, and iris bleeding occurred. Phacoemulsification and posterior chamber lens insertion were conducted in both eyes, and her visual acuity, IOP, anterior chamber depth, and iridocorneal angle have been stable at 9 months since her first visit.@*CONCLUSIONS@#The combined administration of SNRI may cause bilateral acute angle-closure attacks.

Dry Eye Syndrome and Morphological Changes of Meibomian Glands in Type 2 Diabetic Patients

PURPOSE: To evaluate the morphological changes of meibomian glands and dry eye syndrome in patients with type II diabetes. METHODS: The medical records of 72 diabetic patients referred to the ophthalmology clinic for the evaluation of diabetic retinopathy, who had dry eye symptoms, were retrospectively reviewed. RESULTS: A total of 72 patients, with an age of 56.3 ± 13.3 years, were analyzed. The group with diabetic retinopathy (52 patients) had a significantly lower tear film break-up time (p = 0.046), lower Schirmer's test value (p = 0.005), and higher percentage of upper (p = 0.036) and lower (p = 0.017) meibomian gland area losses than the group without diabetic retinopathy (20 patients). According to multilinear regression analyses considering sex, age, and diabetes-related characteristics, the Schirmer's test value was significantly lower with increasing stage of diabetic retinopathy (β = −1.180, p = 0.016). The percentage of upper meibomian gland area loss was significantly increased with increasing age (β = 0.605, p < 0.001), glycosylated hemoglobin (β = 1.881, p = 0.011), and stage of diabetic retinopathy (β = 4.458, p = 0.001). The percentage of lower meibomian gland loss area was significantly increased with increasing age (β = 0.443, p = 0.001) and stage of diabetic retinopathy (β = 4.879, p = 0.001). CONCLUSIONS: In patients with type 2 diabetes, the more severe the diabetic retinopathy, the more likely the meibomian gland loss will occur, so careful and appropriate treatment should be conducted.

Repeatability and Reproducibility of Tear Meniscus Evaluations Using Two Different Spectral Domain-optical Coherence Tomography

PURPOSE: To evaluate the repeatability and reproducibility of inferior tear meniscus measurements using two different spectral domain-optical coherence tomography (OCT), and to compare the inter-device agreements between these devices. METHODS: Two examiners evaluated the tear meniscus depth (TMD) and tear meniscus height (TMH) of 20 eyes in 20 normal subjects using Cirrus OCT and Spectralis OCT with the examiners calculating the TMD and TMH. We analyzed intra-examiner repeatability, inter-examiner reproducibility, and inter-device agreement. RESULTS: The average TMD measurements using the Cirrus OCT and Spectralis OCT devices were 151.25 ± 41.53 µm and 139.10 ± 40.56 µm by examiner 1, respectively, and 152.03 ± 42.77 µm and 138.35 ± 39.70 µm by examiner 2, respectively. The TMHs were 291.90 ± 100.19 µm and 245.43 ± 66.44 µm by examiner 1, respectively, and 288.25 ± 98.72 µm and 244.23 ± 60.69 µm by examiner 2, respectively. The TMDs and TMHs measured using these OCT devices were not statistically significant for intra-examiner and inter-examiner measurements (all, p > 0.05). These devices showed high repeatability (intraclass correlation coefficient ≥ 0.991) for intra-examiner TMD and TMH measurements and the inter-examiner coefficient of variation ranged from 2.04% to 4.32%. The 95% limits of agreement between the two devices were −66.13 to 91.95 µm for TMD and −127.18 to 217.68 µm for TMH. CONCLUSIONS: Both OCT devices are useful for conducting inferior tear meniscus measurements. The inter-device agreement was poor, and the devices were not interchangeable.

Medical Litigations Associated with Cataract Surgery in Korea

BACKGROUND: To analyze the results of court rulings about medical litigations related to cataract surgery in Korea. METHODS: We collected 50 anonymized judgements regarding cataract surgery between 2000 and 2016 and analyzed the reasons for the medical litigations, the court rulings, the reasons for compensation, and the amount claimed and finally awarded. RESULTS: Forty-eight litigations (96%) resulted from errors in treatment, and the reasons were as follows: endophthalmitis, dissatisfaction of visual outcome or ocular discomfort, bullous keratopathy or corneal opacity, retinal detachment, glaucoma or vitreous hemorrhage due to the progression of an underlying diabetic retinopathy, and others in order. Two litigations (4%) arose due to errors in diagnosis. Among the 50 final cases, 21 litigations (42%) were decided in favor of the plaintiff, and 29 litigations (58%) were decided against the plaintiff and dismissed. Ten cases awarded damages to the plaintiffs because of a violation of duty of care, and 11 cases awarded damages due to a violation of informed consent. When comparing cases with errors in diagnosis to cases with errors in treatment, there was no significant difference in the relative risk of a defendant's verdict (P = 0.503). The total amount of awarded damages was KRW 439,124,496 (USD 399,204), and the average amount was KRW 20,910,690 (USD 19,010). CONCLUSION: Nearly half of the cases were decided in favor of the plaintiff due to the violation of informed consent. This study's results will be helpful in understanding the results of medical litigations regarding cataract surgery and reducing future lawsuits.

The Association between Corneal Biomechanical Properties and Initial Visual Field Defect Pattern in Normal Tension Glaucoma

PURPOSE: To investigate the association between corneal biomechanical properties and initial visual field defect pattern in normal tension glaucoma using an Ocular Response Analyzer (ORA; Reichert Instruments, Depew, NY, USA). METHODS: Forty-one patients with normal tension glaucoma were divided into 2 subgroups, 21 patients with initial paracentral scotomas and 20 patients with initial peripheral scotomas. The corneal biomechanical properties of corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg), corneal-compensated IOP (IOPcc) measured by the ORA, central corneal thickness, and Goldmann applanation tonometry were comparatively analyzed between the 2 groups. RESULTS: The patients with initial peripheral scotomas were significantly younger than those with initial paracentral scotomas (49.45 ± 13.33 years vs. 58.14 ± 12.49 years, p = 0.035) and showed more myopia (− 2.42 ± 2.22 diopter vs. − 0.89 ± 2.22 diopter, p = 0.034). The mean CRF was significantly lower in the initial paracentral scotoma group than in the initial peripheral scotoma group. (9.45 ± 1.95 mmHg vs. 10.58 ± 2.05 mmHg; p = 0.041). No significant difference in CH, IOPg, or IOPcc was seen between the groups. CONCLUSIONS: CRF was significantly different between the initial paracentral scotoma group and initial peripheral scotoma group in normal tension glaucoma. Thus, CRF may be useful to predict initial central field loss in normal tension glaucoma.

Progression of Visual Field Loss and Body Mass Index in Normal Tension Glaucoma

PURPOSE: To evaluate the association between body mass index (BMI) and visual field (VF) progression in normal tension glaucoma (NTG) patients. METHODS: We reviewed the medical records of 78 eyes of 78 NTG patients who were treated with eye drops for more than 18 months. Age, sex, existence of hypertension (HTN), diabetes mellitus (DM), refractive error, baseline intraocular pressure (IOP), IOP reduction ratio, baseline VF indices including mean deviation (MD) and pattern standard deviation, VF progression rate (MD slope, dB/year), number of eye drops, and BMI were analyzed. The progression of VF was determined by glaucoma change probability analyses (STATPAC 2) using a Humphrey field analyzer. RESULTS: The mean follow-up in consecutive eyes was 4.4 ± 2.7 years. A total of 18 eyes showed progression and 60 eyes did not. The VF progression rate (p 0.05). However, multiple linear regression analyses showed that a lower BMI was significantly associated with faster VF progression in the progression group (β = 0.078; standard error = 0.030; p = 0.027). CONCLUSIONS: In the group in which VF loss progressed despite treatment with eye drops, a lower BMI was associated with progression of VF loss in NTG patients.

Correlation between Trans-lamina Cribrosa Pressure Difference and Morphologic Parameters of Optic Disc in Normal Tension Glaucoma Patients

PURPOSE: To investigate the relationship between trans-lamina cribrosa pressure difference (TLCPD) and morphologic parameters of optic disc (OD) in normal tension glaucoma (NTG) patients. METHODS: Data from 31 NTG patients (31 eyes) and 29 controls (29 eyes) were analyzed retrospectively. Their cerebrospinal fluid pressure was estimated using diastolic pressure (DBP), body mass index (BMI) and age. TLCPD was defined as the difference of intraocular pressure (IOP) and the estimated cerebrospinal fluid pressure (ECSFP). Measurements of the rim area (RA), disc area (DA), average and vertical cup/disc (C/D) ratio, retinal nerve fiber layer thickness (RNFLT) and cup volume (CV) were taken for all patients using optical coherence tomography. The correlation between TLCPD and morphologic parameters of OD were assessed. RESULTS: There were no significant differences between the two groups in terms of age, DBP, IOP and spherical equivalent (SE) and BMI. The mean ECSFP was significantly higher in the controls (10.7 ± 2.8 vs. 12.2 ± 2.2 mm Hg, p = 0.031) and TLCPD was significantly higher in patients (2.4 ± 2.1 vs. 4.9 ± 3.7 mm Hg, p = 0.002). In the NTG group, there was a negative correlation between TLCPD and RA (r = -0.595) and positive correlations between TLCPD and the average C/D ratio (r = 0.504), vertical C/D ratio (r = 0.434) and CV (r = 0.420). Average RNLFT was also significantly correlated with TLCPD (r = -0.500) and RNFLT for four quadrants, except the nasal quadrant, in NTG patients. CONCLUSIONS: NTG patients had higher TLCPD. A higher TLCPD was associated with a narrower RA, larger C/D ratio, and thinner RNFLT.

Change in Corneal Biomechanical Parameters in Diabetes Mellitus

PURPOSE: In this study, we examined the changes in corneal biomechanical parameters in patients with diabetes mellitus (DM). METHODS: Fifty patients with DM were divided into 2 subgroups, 25 diabetic patients with glycated hemoglobin (HbA1c 7%) and compared with the eyes of 80 healthy subjects. Corneal biomechanical parameters were measured using ocular response analyzer (ORA). Differences in corneal biomechanical properties between healthy subjects and diabetic patients were compared. Additionally, differences in corneal biomechanical properties between diabetic patients with HbA1c 7% were compared. RESULTS: Corneal hysteresis, corneal resistance factor and central corneal thickness (CCT) were statistically significantly higher in patients with diabetes compared to healthy subjects. Goldmann tonometer, non-contact tonometer and Goldmann-correlated intraocular pressure (IOPg) were statistically significantly higher in patients with DM compared to healthy subjects, but corneal compensated IOP (IOPcc) was not statistically significantly different between healthy subjects and diabetic patients. However, corneal biomechanical parameters, which were statistically significantly different between healthy subjects and DM patients, were not statistically significantly different between diabetic patients with HbA1c 7%. CONCLUSIONS: Considering that corneal properties are different between diabetic patients and healthy subject, IOPcc measured with ORA is considered clinically useful for measuring IOP as it reflects CCT and biomechanical properties that should be revised. In diabetes, changes in corneal biomechanical properties depend on long-term glucose control rather than short-term glucose control.

Diagnostic Availability of Ocular Response Analyzer in Korean Patients with Normal Tension Glaucoma

PURPOSE: To compare the parameters measured with the ocular response analyzer (ORA; Reichert Inc., Depew, NY, USA) between normal control subjects and patients with normal tension glaucoma (NTG) and to investigate clinical usefulness of ORA. METHODS: Intraocular pressure (IOP) and central corneal thickness (CCT) were measured using the Goldmann applanation tonometer (GAT) in 100 eyes of 100 normal subjects and 100 eyes of 100 NTG patients. Four types of ORA parameters, corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated IOP (IOPg), and corneal-compensated IOP (IOPcc) were also measured. RESULTS: The mean CH values were 11.2 mm Hg and 10.3 mm Hg and the mean CRF values were 10.8 mm Hg and 9.9 mm Hg in the normal subjects group and the NTG group, respectively. Mean CH and CRF were significantly lower in NTG patients (p < 0.001) and the IOPcc were higher than normal subjects (p = 0.004). IOPg was in agreement with the GAT IOP (ICC = 0.811) and IOPcc was not correlated with CCT. The cut-off value of 'IOPcc - IOPg' as the diagnostic standard parameter was -0.05 mm Hg (sensitivity; 76%, specificity; 55%). CONCLUSIONS: IOPg measurements were similar to GAT IOP, and other ORA parameters (CH, CRF, IOPcc) were significantly different between normal subjects and NTG patients. Consequently, the difference of IOPcc and IOPg could be a useful parameter in NTG diagnosis.

Diurnal Variation in Intraocular Pressure Measured by Ocular Response Analyzer in Korean Patients with Normal Tension Glaucoma

PURPOSE: To analyze the diurnal change in intraocular pressure (IOP) and corneal biomechanical properties measured using the Ocular Response Analyzer (ORA; Reichert Inc., Depew, NY, USA) in Korean patients with normal tension glaucoma (NTG) patients. METHODS: Intraocular pressure (Goldmann applanation tonometer IOP [GAT IOP], Goldmann-correlated IOP [IOPg], corneal-compensated IOP [IOPcc]) and corneal hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT) were measured in 21 eye of NTG patients (12 males, 9 female) at 3 hour intervals for 48 hours using ORA. We recorded the time of each parameter that showed the lowest and the highest values of during the 48 hour testing period (Day 1 and Day 2) and evaluated the change of diurnal variation using Repeated measures analysis of variance (Re-ANOVA). RESULTS: Peak IOP measured with GAT and ORA occurred at 6 AM-9 AM, 3 PM-6 PM and the trough IOP at 9 PM-12 AM during the 48 hour period. CCT, GAT IOP, IOPcc and IOPg measurements showed statistically significant variations (p0.05). CONCLUSIONS: In Korean NTG patients, IOP exhibits significant diurnal variation, with higher values during the dawn and afternoon and lower values before retiring. Clinically, measurements of IOP performed in the afternoon could aid in the detection of relatively elevated IOP.

Choroidal Thickness in Primary Open-Angle Glaucoma Using Spectral-Domain Optical Coherence Tomography

PURPOSE: To evaluate the choroidal thickness in patients with primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) using spectral-domain optical coherence tomography (SD-OCT), and to explore the relationship between the choroidal thickness and glaucoma. METHODS: A retrospective analysis was performed on patients who had been diagnosed with POAG or NTG at Ewha Womans University, Mokdong Hospital. SD-OCT scans were obtained to estimate retinal nerve fiber layer (RNFL) thickness, macular thickness, and subfoveal and peripapillary choroidal thickness in groups of POAG patients, NTG patients, and normal controls. RESULTS: A total of 21 patients with POAG, 53 patients with NTG, and 42 normal subjects were enrolled in this study. RNFL thickness and macular thickness were significantly thinner in the POAG and NTG groups compared to the normal subjects. In contrast, there were no significant differences in subfoveal and peripapillary choroidal thickness among the 3 groups. There was no significant correlations between the peripapillary choroidal thickness and retinal nerve fiber layer thickness. CONCLUSIONS: Choroidal thickness does not seem to differ between glaucoma patients and normal subjects, and there were no significant correlations between the choroidal thickness and glaucomatous optic neuropathy.

Corneal Biomechanical Properties of Normal Tension Glaucoma in Young Patients Evaluated with the Ocular Response Analyzer

PURPOSE: To evaluate the corneal biomechanical properties and clinical characteristic of normal tension glaucoma (NTG) in young patients. METHODS: We compared corneal biomechanical properties using an Ocular response analyzer (ORA) of under age 40 of 37 eyes of patients with NTG and 42 eyes of normal group. RESULTS: The mean corneal resistance factor (CRF) and mean corneal hysteresis (CH) were significantly lower in NTG eyes (CRF, 9.2 +/- 2.1 mm Hg; CH, 9.8 +/- 1.8 mm Hg) than in normal eyes (CRF, 10.7 +/- 2.3 mm Hg; CH, 10.9 +/- 2.0 mm Hg; p = 0.01, p < 0.01). CH and CRF were associated with central corneal thickness (CCT) (CH; beta = 0.354, p < 0.01, CRF; beta = 0.348, p < 0.01) and glaucoma status (p < 0.01, p < 0.01). CONCLUSIONS: The CRF and CH were significantly lower in NTG group while IOP cc was not significantly different between the group. In diagnosing the NTG in young patients, ORA maybe useful for distinguishing between the glaucoma eyes and normal eyes.

Herpes Zoster Ophthalmicus in Patients Younger than 50 Years Versus 50 Years and Older

PURPOSE: To study the clinical course of herpes zoster ophthalmicus (HZO) and to compare the demographics, treatments, and outcomes in patients under 50 years of age versus patients 50 years of age or older at the time of diagnosis. METHODS: A retrospective chart review was performed of 102 patients who were diagnosed with HZO between January 1, 2008 and December 31, 2010. Baseline demographics and clinical characteristics between patients with an onset of HZO under the age of 50 years and patients with an onset of HZO at the age of 50 years or older were compared. RESULTS: Similar numbers of patients were affected with HZO in the younger and older age groups (n = 44, 43.1%, vs. n = 58, 56.9%). The mean +/- SD of age was 50.6 +/- 21.8 years (range, 3-89 years) and the most common decade of HZO onset was between 50 and 59 years. Gender and disease laterality were not statistically different between the 2 groups. No significant difference was found regarding the presence of any ocular manifestation between the groups; however, anterior uveitis was more frequent in the younger patients (p = 0.04). The number of patients with immunosuppressive therapy was higher in the younger age group (p = 0.01). CONCLUSIONS: HZO-affected patients under the age of 50 years and older than 50 years were equally distributed, with the most common decade of onset between the age of 50 and 59 years. Younger patients had a higher incidence of anterior uveitis and immunosuppressive therapy due to underlying systemic diseases.

The Association Between Corneal Biomechanical Properties and Progression of Visual Field Loss in Normal Tension Glaucoma

PURPOSE: To evaluate the association between corneal biomechanical properties and progression of visual field loss in normal tension glaucoma. METHODS: This study enrolled 73 eyes of 73 patients with normal tension glaucoma who were undergoing medical treatment, and classified them into progressing and nonprogressing groups by visual field trend analysis. The corneal biomechanical properties measured by the Ocular Response Analyzer (ORA; Reichert Instruments, Depew, NY, USA), central corneal thickness, and Goldmann applanation tonometry were comparatively analyzed between the 2 groups. RESULTS: Twenty-six eyes reached a progression endpoint. The prevalence of hypertension was higher in the progressing group (42.3%, progressing, 17.0%, nonprogressing; p = 0.03). Progressing eyes had lower corneal hysteresis (9.1 +/- 1.3 vs. 9.8 +/- 1.5 mm Hg, p = 0.03) and lower corneal resistance factor (9.5 +/- 1.5 vs. 10.4 +/- 1.4 mm Hg, p = 0.01) compared with nonprogressing eyes. Upon multivariate analysis, the presence of hypertension (odds ratio [OR] = 3.46, p = 0.03) and corneal hysteresis (CH) (OR = 0.66 per mm Hg lower, p = 0.02) remained statistically significant. CONCLUSIONS: The CH measurement with ORA was significantly associated with risk of visual field progression in normal tension glaucoma. Eyes with lower CH had a greater risk of progression of visual field loss than those with higher CH.

Reproducibility of Ocular Response Analyzer and Comparison with Goldmann Applanation Tonometer and Non-Contact Tonometer

PURPOSE: To evaluate the inter- and intra-observer variability of ocular response analyzer (ORA) measurements, and to evaluate the relationships among the intraocular pressures (IOPs) obtained by ORA, Goldmann applanation tonometer (GAT) and non-contact tonometer (NCT). METHODS: The present study included 45 normal eyes from 45 volunteers. Three masked observers performed ORA measurements. NCT and GAT measurements were performed by one independent observer. The reproducibility of ORA was assessed by ANOVA-based intraclass correlation coefficient (ICC) and coefficient of variation (CV). Comparison among the tonometers was performed using the Bland-Altman plot and paired t-test. RESULTS: The ICC for inter-observer reproducibility of ORA parameters was 0.90 to 0.97. The corresponding CV values were 13.2% to 19.1%. The intra-observer ICC values for IOP cc were 0.78 to 0.88. CV was 11.2% to 16.8%. For CRF, ICC values were 0.80 to 0.84 with CV values as 11.6% to 15.9%. For CH, ICC values were 0.74 to 0.82 and CV values were 13.0% to 15.9%. The difference in mean IOP values between IOP cc and IOP g was statistically significant (p = 0.04). However, no difference was found among other tonometers, and only IOP cc did not result in significant correlation with central corneal thickness (CCT) (p = 0.38). CONCLUSIONS: The intra- and inter-observer reproducibility was substantial for IOP cc, IOP g, CH and CRF, for all observers. Additionally, IOP measured with ORA did not result in significant differences from GAT and NCT.

Treatment Outcome of Phacotrabeculectomy and Trabeculectomy in Patients with Cataracts and Glaucoma

PURPOSE: To compare the treatment outcome and complications of phacotrabeculectomy and trabeculectomy in patients with glaucoma and cataracts. METHODS: The authors of the present study retrospectively reviewed the records of 56 eyes that underwent phacotrabeculectomy and trabeculectomy with mitomycin-C between March 2006 and December 2009 in patients with glaucoma and cataracts. The change of intraocular pressure (IOP) and number of glaucoma medications up to 24 months postoperatively were compared and the treatment failure rate as well as postoperative complications analyzed. RESULTS: IOP and number of glaucoma medications at 24 months after surgery were similar in the 2 groups. Additionally, both groups showed a significant decrease in IOP and number of glaucoma medications after surgery. The cumulative failure rates, frequency and distribution of postoperative complications were also similar in both groups and conjunctival bleb leak was the most common complication. CONCLUSIONS: Both phacotrabeculectomy and trabeculectomy showed long-term IOP reduction and a similar failure rate and complications. Therefore, both can be considered as a primary surgical treatment in patients with glaucoma and cataracts. In patients who need strict IOP control, trabeculectomy can be preferentially considered. If patients have visually significant cataracts or greater visual needs, phacotrabeculectomy can be considered.

Accuracy of Intraocular Lens Power Calculations According to the Formulas and Anterior Chamber Depth in Short Eyes

PURPOSE: To evaluate the accuracy of intraocular lens (IOL) power calculations according to the chosen formulas and anterior chamber depths in eyes with short axial lengths. METHODS: A retrospective analysis was performed on 57 eyes of 50 patients (axial length < 22.0 mm) and 42 eyes of 36 patients (22.0 mm < or = axial length < 25.0 mm) who underwent cataract surgery. IOL power was calculated with the SRK II, SRK/T, Binkhorst, Holladay I, and Hoffer Q formulas. The differences between the predicted refraction and the actual refraction were compared and analyzed. The errors according to the anterior chamber depth were also evaluated. RESULTS: The SRK II formula showed a lower predictive accuracy, and the other formulas showed similar accuracies in eyes with short axial lengths. The Holladay 1 and Hoffer Q formulas showed good predictive accuracies in eyes with short axial lengths. Hyperopic shift tended to occur with all formulas in eyes with short axial lengths. When using SRK II and SRK/T formulas, a correlation between axial length and hyperopic shift was observed, with shorter axial length patients shifting to more hyperopic conditions. In eyes with short axial lengths, larger hyperopic shifts tended to occur in eyes with relatively deeper anterior chambers. CONCLUSIONS: In eyes with short axial lengths, preoperative predicted IOL power showed good accuracies with Holladay 1 and Hoffer Q formulas. Preoperative anterior chamber depth and axial length had a strong influence on the accuracies of predicted IOL power.

Comparison of Retinal Nerve Fiber Layer Thickness in Early Normal-Tension Glaucoma and Early Primary Open-Angle Glaucoma

PURPOSE: To investigate the comparison of retinal nerve fiber layer (RNFL) thickness parameters measured by optical coherence tomography (Stratus OCT 3000TM) and visual field indices in early normal-tension glaucoma (NTG) and early primary open-angle glaucoma (POAG). METHODS: Sixty-one early normal-tension glaucomatous eyes, 21 early primary open-angle glaucomatous eyes and 34 healthy control eyes were enrolled in this cross-sectional study. Each subject received a visual field test (Humphrey C30-2) and the fast RNFL thickness algorithm test by OCT. The correlations between RNFL thickness and visual field indices were analyzed. The sensitivity and specificity for the detection of early glaucoma were determined with the area under the receiver operating characteristics curve (AUROC). RESULTS: All RNFL thickness values except for the temporal quadrant RNFL thickness were significantly decreased in the early NTG and POAG groups (p<0.05). In early POAG, the average and superior quadrant RNFL thicknesses were significantly thinner than in the early NTG group. Significant correlations were observed between the PSD and the average and superior quadrant RNFL thicknesses in the early NTG and POAG groups (p<0.05). The average RNFL thickness for early glaucoma had the widest AUROC among all of the parameters. CONCLUSIONS: In the early NTG group with visual field defects similar to those of early POAG, RNFL defects measured by OCT were less severe, particularly in the average and superior quadrant RNFLs.

Longitudinal Analysis of Retinal Nerve Fiber Layer Thickness With GDx-VCC in Glaucoma Suspect

PURPOSE: The changes of retinal nerve fiber layer thickness with GDx-VCC were analyzed to assess the use of this instrument for longitudinal follow-up of retinal nerve fiber layers. METHODS: From July 2004 to July 2007, patients suspected of glaucoma were measured with GDx-VCC at baseline and measurements were repeated at a minimum interval of 12 months. The medical records of 150 patients were reviewed and 42 patients that showed glaucomatous visual field progression in 36 months were classified into a "progression group" and 108 patients with no visual field loss were classified into a "nonprogression group". RESULTS: In the nonprogression group, the temporal superior-nasal-inferior-temporal (TSNIT) average and theinferior average showed statistically significant changes for the follow up periods. However, in theprogression group, there were no parameters with significant changes even though glaucomatous visual field loss was found. The visual field progressed at a rate of 0.1dB/year in the progression group but the relationship between MD, PSD and GDx-VCC parameters could not be established. CONCLUSIONS: GDx-VCC may not be sufficient for longitudinal assessment of the RNFL, especially during the early glaucomatous visual field changes. The progression of glaucoma only with GDx-VCC should be cautiously evaluated, and confirmation with the visual field which elucidates early glaucomatous changes is necessary. Further study is needed before GDx-VCC can be recommended as the instrument for longitudinal assessment.

Comparison of RNFL Thickness Measured by Two Different Kind of OCT in NTG Patients

PURPOSE: To compare retinal nerve fiber layer (RNFL) thicknesses with two types of OCT in patients with normal tension glaucoma (NTG) and early NTG. METHODS: We evaluated the RNFL thicknesses of 101 eyes in 101 patients using Fourier domain OCT and time domain OCT. We compared the measured RNFL thicknesses according to the subject groups and the type of OCT. We calculated the area under the receiver operating characteristic curve (AUROC) to determine the best parameters with which to make a diagnosis of NTG or early NTG. RESULTS: The RNFL thicknesses measured by 3D OCT were greater than that measured by Stratus OCT for all of the groups. The RNFL thickness in each group was statistically significantly different in the superior quadrant, the inferior quadrant, and the 1 and 2 o'clock positions when using 3D OCT. It was statistically significantly different in the superior, temporal, and inferior quadrant, as well as the 1, 7, 8, 9, 10 and 11 o'clock positions when using Stratus OCT. The largest AUROC was found for the inferior quadrant thickness (0.773) using Stratus OCT and the 1 o'clock thickness (0.712) using 3D OCT when comparing normal patients and those with suspected NTG. The largest AUROC was found for the inferior quadrant thickness (0.888) using Stratus OCT and the superior quadrant thickness (0.802) using 3D OCT when comparing normal patients and those with early NTG. The AUROC was greater in the temporal and inferior quadrants and in the 6, 7, 8, 9 and 10 o'clock thicknesses using Stratus OCT compared to the 3D OCT in differentiating patients with suspected NTG from normal patients. The AUROC found using 3D OCT compared to the Stratus OCT was greater only in the 1 o'clock thickness (p<0.05). The AUROC differentiating patients with early NTG from normal patients was greater in the temporal, inferior, nasal quadrant, and in the 5, 6, 7, 8, 9, 10 and 11 o'clock positions using the Stratus OCT compared to the 3D OCT (p<0.05). CONCLUSIONS: The RNFL thicknesses measured using 3D OCT were generally greater than those measured using Stratus OCT. The largest AUROCs for differentiating patients with suspected NTG and early NTG from normal patients were in the 1 o'clock position and the superior quadrant RNFL thickness using 3D OCT and the inferior quadrant RNFL thickness using Stratus OCT. The AUROCs using the 3D OCT parameters were less than those from the Stratus OCT when comparing normal patients and those with suspected or early NTG.