Long-term outcomes of prismatic correction in partially accommodative esotropia

Purpose

In partially accommodative esotropia (PAET), prism glasses can correct small angles of residual esotropia but the long-term effect of prismatic correction alone without surgery has not been reported. We aimed to investigate the long-term outcome of prism glasses after full hypermetropic correction for PAET.

Methods

This retrospective, case-control study was performed for children aged 10 years or younger with a residual esotropia of ≤ 20 prism diopters (PD) after full hypermetropic correction who were fitted with prism glasses and followed-up for 3 years or more. Clinical characteristics and the angle of esodeviation were obtained at each follow-up examination. Successful motor outcome after 3 years of prismatic correction was determined if the residual angle of esotropia after full hypermetropic correction was ≤ 10PD. Patients who eventually weaned off prism glasses were noted.

Results

Among 124 patients, 30.6% achieved success and 7.3% weaned off prism glasses after 3 years of prism-wear. Smaller amount of latent esodeviation (P = 0.001) revealed by prism adaptation and good fusional response at near with the Worth 4-dot test were significant prognostic factors of success by multivariate analysis (P = 0.033). After 3 years of wearing prism glasses, the rate of improvement in stereoacuity was higher in the Success group (60.5% vs 27.9%) (P = 0.001), however, there was no significant difference between the prism-weaned group and prism-wearing group within the Success group (P>0.05).

Conclusion

Prism glasses for small angle PAET can be a treatment option in patients who have a small angle of latent esodeviation revealed by prism adaptation and good sensory fusion at near. Otherwise, early surgery may be advisable as the majority of patients showed suboptimal outcome even after long-term prism-wear.

Nonarteritic anterior ischemic optic neuropathy is associated with cerebral small vessel disease

We investigated the presence of cerebral small vessel disease (SVD) in patients with nonarteritic anterior ischemic optic neuropathy (NAION) compared to control subjects without NAION to identify the association between NAION and cerebral SVD. We retrospectively reviewed the cases of 63 patients with NAION and 2749 control subjects without any neurologic and ocular diseases including NAION who underwent careful medical interviews, ophthalmic examinations, and magnetic resonance imaging (MRI) studies of the brain. We assessed and compared the degree of cerebral SVD on the MRIs. The patients with NAION presented with cerebral SVD more frequently than controls (68% versus 37%, respectively, p<0.001), which was also observed after adjusting for age, sex, comorbid conditions including hypertension, diabetes, and dyslipidemia, and smoking using the standardized mortality ratio (68% vs. 37%, p<0.001). A multivariate logistic regression analysis showed that the odds of cerebral SVD were 4.86 (95% CI, 2.10 to 11.24, p<0.001) times higher in patients with NAION than in the controls. We found that there was an association between cerebral SVD and NAION even after adjusting for age, sex, and medical histories. Clinicians should consider brain MRI scans in patients with NAION to prevent neurological impairment after cerebral SVD.

Risk of Nonarteritic Anterior Ischemic Optic Neuropathy After Cataract Surgery

PURPOSE

To determine whether the development of nonarteritic anterior ischemic optic neuropathy (NAION) is increased after receiving cataract surgery in a large general population.

DESIGN

Nationwide, population-based, retrospective cohort study.

METHODS

Setting: A 12-year nationwide, population-based, retrospective cohort study including 1,025,340 beneficiaries in the 2002-2013 Korean National Health Insurance Service database.

PATIENTS

We identified 40,356 patients who had undergone cataract surgery and matched non-cataract surgery controls (1:2) using estimated propensity scores in reference to age, sex, demographics, comorbidities, and co-medications.

OBSERVATIONS

Kaplan-Meier curves and Cox proportional hazard models were generated to determine the risk of developing NAION in the cataract surgery group compared to the non-cataract surgery group.

MAIN OUTCOME MEASURES

Effect (hazard ratio [HR]) of cataract surgery on NAION development.

RESULTS

The 10-year incidence probability of NAION was 0.70% (95% confidence interval [CI], 0.55%-0.86%) in the cataract surgery group and 0.27% (95% CI, 0.25%-0.29%) in the non-cataract surgery group (P < .0001, log-rank test). The cataract surgery group had an increased risk of developing NAION compared to the non-cataract surgery group (HR = 1.80; 95% CIs, 1.46-2.21) even after adjusting for demographics, comorbidities, Charlson comorbidity index, and co-medications.

CONCLUSION

Our results suggest that patients undergoing cataract surgery have an increased risk of NAION.

Efficacy of a new automated method for quantification of corneal neovascularisation

BACKGROUND/AIMS

To evaluate the efficacy of a new automated method for quantification of corneal neovascularisation (NV).

METHODS

An in-house software for automated measurement of corneal NV was developed. Anterior segment photographs (ASPs) of 81 consecutive patients with corneal NV were analysed using our newly developed software. Manual measurements were performed by three independent examiners using ImageJ software V.1.48 (National Institute of Health, Bethesda, Maryland, USA). Interobserver reliability of the automated and manual methods, and correlations between the results of both methods were evaluated.

RESULTS

The automated method showed a strong interexaminer reliability (intraclass correlation coefficient (ICC)=0.994), which was slightly better than the manual method (ICC=0.958). A significant correlation was found between the results of both methods (p<0.001 for all three examiners). The time spent for analysis of each ASP was significantly reduced in the automated method compared with the manual method (p<0.001 for all three examiners).

CONCLUSIONS

Our newly developed automated method for quantification of corneal NV was more reproducible and time-saving compared with the manual method. Our method can be useful for diagnosis and monitoring diseases causing corneal NV.

Amblyopia risk factors in congenital nasolacrimal duct obstruction: A longitudinal case-control study

Purpose

To investigate longitudinal changes in risk factors for amblyopia in children treated with congenital nasolacrimal duct obstruction (CNLDO).

Methods

Retrospective observational case control study. A total of 446 children under 4 years of age who underwent probing and/or intubation for CNLDO between January 2004 and January 2018, and 446 age-matched controls were included. Cycloplegic refraction and ocular alignment were investigated at the time of treatment and after at least one year of symptom improvement. Children were classified as having amblyopia risk factors on the basis of the American Association for Pediatric Ophthalmology and Strabismus guideline in 2013.

Main outcome measures

The prevalence of amblyogenic refractive errors, and determinants associated with the presence of amblyogenic refractive errors in CNLDO patients.

Results

The prevalence of amblyogenic refractive errors in CNLDO patients (5.4%) was similar to that of the control group (6.5%) (P = 0.571). After one year of symptom improvement in CNLDO patients, the prevalence of amblyogenic refractive errors was 4.7%. There was no difference in the prevalence of amblyogenic refractive errors between unilateral and bilateral CNLDO patients. Multivariate analysis revealed that manifest strabismus was the only risk factor related with the presence of amblyogenic refractive errors (odds ratio = 6.383, confidence interval = 1.205–33.826, P = 0.029).

Conclusions

This study found no evidence to suggest that the prevalence of amblyopia risk factors is higher in CNLDO patients compared with normal controls. Manifest strabismus was the only determinant associated with the presence of amblyogenic refractive errors.

Automatic computer-aided analysis of optic disc pallor in fundus photographs

PURPOSE

Assessment of optic disc pallor in fundus photographs may be frequently misinterpreted due to the subjective nature of interpretation. We developed a fully automatic computer-aided detection (CAD) system for optic disc pallor using colour fundus photographs and evaluated the accuracy of the system.

METHODS

A newly proposed CAD system was developed for automated segmentation and image analysis of optic disc pallor, and a logistic regression model was developed for risk analysis. A total of 230 photographs with variable degree of optic disc pallor, and 123 normal optic discs confirmed by optical coherence tomography were tested for validation of the software. Sensitivity and specificity of the CAD system in automatic detection of optic disc pallor using colour fundus photographs were evaluated. The results of manual detection of optic disc pallor on fundus photographs by two independent ophthalmologists were compared with the efficacy of the CAD system.

RESULTS

The fully automated CAD system achieved a sensitivity of 95.3% and a specificity of 96.7% for detecting optic disc pallor in colour fundus images. The overall accuracy of the CAD system was 96.1%, which was superior to the results of manual detection by individual examiners.

CONCLUSIONS

We developed an automated CAD system that successfully detected optic disc pallor in fundus photographs. The proposed algorithm can assist the clinical judgement of ophthalmologists for detecting optic disc pallor in fundus photographs.

Risk of ischemic stroke after third, fourth, and sixth cranial nerve palsies in type 2 diabetes

BACKGROUND

The aim of this study was to define the risk of ischemic stroke among newly diagnosed type 2 diabetes (T2D) patients who developed ocular motor cranial nerve (CN) palsies.

METHODS

From the National Health Insurance Service - National Sample Cohort database (2002-2013) of a random sample of 1 025 340 Koreans, patients with newly diagnosed T2D aged ≥20 years were included in the study. The incidence of ocular motor CN palsies was identified using diagnostic codes for third, fourth, and sixth CN palsies. To determine the effect of incident ocular motor CN palsy on subsequent ischemic stroke, covariate Cox regression was used (Model 1 included only ocular motor CN palsy as a time-varying covariate; Model 2 included ocular motor CN palsy and demographic information; Model 3 included all variables in Model 2 as well as comorbidity, concomitant medication, and the Charlson comorbidity index score).

RESULTS

Of 45 820 T2D patients, 75 developed ocular motor CN palsy and 1411 had ischemic stroke. Four patients experienced ischemic stroke after the development of ocular motor CN palsy. Incident ocular motor CN palsy was associated with the subsequent risk of ischemic stroke in Models 1, 2 and 3 (hazard ratios [95% confidence intervals] 3.74 [1.40-9.98], 3.33 [1.25-8.89], and 2.96 [1.11-7.92], respectively). Male sex, older age, and lower income were associated with an increased risk of ischemic stroke. Among confounders, hypertension, atrial fibrillation, and congestive heart failure were associated with the risk of ischemic stroke.

CONCLUSIONS

Physicians should pay more attention to manageable risk factors of ischemic stroke when diabetic patients suffer from ocular motor CN palsies.

Risk of Stroke After Nonarteritic Anterior Ischemic Optic Neuropathy

PURPOSE

To determine whether nonarteritic ischemic optic neuropathy (NAION) raises the risk of subsequent stroke in the general population.

DESIGN

Population-based, retrospective cohort study.

METHODS

Setting: Nationwide, population-based, retrospective cohort study.

PATIENTS

Of 1 025 340 beneficiaries in the National Health Insurance Service-National Sample Cohort database (2002-2013), we included 400 952 eligible individuals in the analysis.

OBSERVATIONS

To determine the effect of incident NAION on the occurrence of subsequent stroke, we used time-varying covariate Cox regression models. Model 1 included only incident NAION as a time-varying covariate. Model 2 included Model 1 and defined demographics. Model 3 included Model 2, comorbidity, co-medication, and Charlson index score.

MAIN OUTCOME MEASURES

Effect (hazard ratio [HR]) of NAION on stroke development.

RESULTS

Of 400 952 eligible individuals, 1125 patients developed NAION and 16 998 patients suffered from stroke. NAION was not associated with an increased risk of subsequent stroke in Model 1, with HR of 1.31 (95% confidence interval [CI], 0.89-1.92). This was consistent, after adjusting for demographics and/or confounding factors, in Model 2 (HR = 1.19, 95% CI, 0.81-1.75) and Model 3 (HR = 1.10, 95% CI, 0.75-1.62).

CONCLUSIONS

Our results suggest that NAION per se is not associated with a subsequent risk of stroke in the general population.

Efficacy of Polytetrafluoroethylene/Polylactide-co-glycolide (PTFE/PLGA) Laminate and PTFE/PLGA Laminate Containing Slow-Releasing Thalidomide in Delayed Adjustable Strabismus Surgery in a Rabbit Model

Purpose: To evaluate the efficacy of polytetrafluoroethylene/polylactide-co-glycolide (PTFE/PLGA) laminate containing sustained-release thalidomide for delayed adjustable strabismus surgery. Methods: This is a prospective, masked-observer, controlled study using 50 eyes of 25 rabbits. After superior rectus muscle (SRM) recession, a PTFE/PLGA laminate containing thalidomide (group PT, 20 eyes), PTFE/PLGA laminate alone (group P, 20 eyes), or no barrier (group C, 10 eyes) were applied around the SRM. Delayed adjustment was performed at postoperative 3 or 5 weeks. Adjustability, adjustment lengths, adjustment forces, and degrees of adhesion were evaluated. Results: Both groups PT and P showed significantly better adjustability compared to group C at both 3 weeks (100%, 80%, and 0%, respectively) and 5 weeks (100%, 90%, and 0%, respectively). Between groups PT and P, adjustability, adjustment lengths, and forces were not significantly different at 3 and 5 weeks. Group PT showed a significantly lower grade of adhesion between SRM and sclera (SRM/S) compared to group C at both 3 weeks (p = 0.007) and 5 weeks (p = 0.001, respectively). Group P showed no significant difference in adhesion between SRM/S compared to group C at 3 weeks (p= 0.302) but had a lower grade of adhesion after 5 weeks (p = 0.007). There was no significant difference between groups PT and P at 3 weeks (p= 0.143) and 5 weeks (p= 0.716). Conclusions: PTFE/PLGA laminate containing sustained-release thalidomide was effective in reducing adhesion and allowed delayed adjustment in all eyes. However, PTFE/PLGA laminate alone was also equally effective in reducing adhesion compared to controls.

Efficacy of collagen matrix implant on adhesions in restrictive strabismus: An experimental study in a rabbit model

PURPOSE

To determine the efficacy of a biodegradable collagen matrix implant (Ologen, Aeon Astron Europe BV, Leiden, the Netherlands) in reducing adhesions in a rabbit model of restrictive strabismus.

METHODS

A prospective, masked-observer, controlled experimental study was performed. Sixty superior rectus muscles of 30 rabbits were resected and Marlex mesh was fixed beneath the resected muscle using nonabsorbable suture. Forty eyes underwent one of two different procedures; the resected muscle was wrapped with preserved human amniotic membrane (AM group) or Ologen (Ologen group). Randomly selected 20 eyes served as controls. Eyes were enucleated at 4 weeks after surgery to measure the severity of adhesion using a push pull gauge. Histopathological examination was performed.

RESULTS

At postoperative week four, the average tensile strength of the myoscleral adhesion was significantly lower in the Ologen group (151.8 ± 42.7 gram force) compared to controls (347.9 ± 68.6 gram force) and AM group (193.0 ± 44.3 gram force) (p < 0.001 and p = 0.045, respectively). Ologen group showed significantly lower degree of acute inflammation, chronic inflammation and rectus muscle fibrosis compared with controls (all p < 0.01). The degree of chronic inflammation was significantly lower in the Ologen group compared with AM group (p = 0.012).

CONCLUSION

Compared to amniotic membrane, Ologen is more effective in reducing mesh-related extraocular muscle adhesions in a rabbit model of restrictive strabismus.

Prevalence and risk factors of myopia in adult Korean population: Korea national health and nutrition examination survey 2013-2014 (KNHANES VI)

PURPOSE

To evaluate the prevalence and risk factors of myopia in adult Korean population.

METHODS

Population-based cross-sectional data of 3,398 subjects aged 19 to 49 years was obtained using the Korea National Health and Nutrition Examination Survey 2013-2014 (KNHANES VI). Data, including refractive errors and potential risk factors were analyzed. The prevalence and risk factors of myopia, low myopia, and high myopia-defined as a spherical equivalent (SEQ) ≤ -0.5 diopters (D), -6.0 D < SEQ <-0.5 D, and SEQ ≤ -6.0 D, respectively-were evaluated.

RESULTS

The prevalence of myopia and high myopia were 70.6 (standard error (SE), ±1.1)% and 8.0 (SE, ±0.6)%, respectively. In multivariable analysis, younger age, higher education (≥12 years), parental myopia, lower serum 25-hydroxyvitamin D (25(OH)D) concentration (<9 ng/mL), longer time spent on near work (≥3 hours/day), and higher white blood cell (WBC) count (5-8.9 x 103) were associated with increased prevalence of both myopia and high myopia. Serum 25(OH)D concentration of ≥ 9 ng/ml was significantly associated with decreased prevalence of high myopia in participants with near work of ≥3 hours/day, although the effect was not significant in myopia and low myopia.

CONCLUSIONS

The prevalence of myopia and high myopia in Korean adults was substantially high, which increased with decreasing age. In addition to parental myopia, the serum 25(OH)D concentration, near work and inflammation reflected by WBC counts may be associated with myopia.

Inner macular layer thickness by spectral domain optical coherence tomography in children and adults: a hospital-based study

Purpose

To establish the normative ranges of macular ganglion cell layer (mGCL) and macular inner plexiform layer (mIPL) thickness using Spectralis spectral domain optical coherence tomography (SD-OCT) (Heidelberg Engineering, Inc., Heidelberg, Germany) in both Korean children and adults, and to determine factors associated with mGCL and mIPL thickness.

Methods

We conducted a retrospective, observational study of 573 healthy subjects (5–70 years old) who underwent comprehensive ophthalmic examinations in a single institution. Each inner retinal layer thickness was measured using SD-OCT and automatic segmentation software. Cross-sectional analysis was used to evaluate the effect of gender, age and ocular parameters on mGCL and mIPL thickness. Normative ranges of mGCL and mIPL thickness according to age, gender and factors associated with mGCL and mIPL thickness were measured.

Results

The mean mGCL and mIPL thickness were 40.6±2.8 and 33.8±2.0 µm, respectively. Determinants of inner sector mGCL thickness were circumpapillary retinal nerve fibre layer (cpRNFL) thickness (β=1.172, p<0.001), age (β=−0.019, p=0.021) and male gender (β=1.452, p<0.001). Determinants of inner sector mIPL thickness were cpRNFL (β=0.952, p<0.001) and male gender (β=1.163, p<0.001). The inner sector mGCL and mIPL thickness increased significantly with age in children (β=0.174, p=0.009 and β=0.115, p=0.013), and then decreased in adults (β=−0.070, p<0.001 and β=−0.024, p=0.032). In the case of outer sectors, mGCL and mIPL thickness were not significantly related to age and gender.

Conclusions

This study ensured a normative range of the mGCL and mIPL thickness using Spectralis OCT. Gender, age and cpRNFL thickness significantly correlated with mGCL and mIPL thickness. This information should be considered in the interpretation of SD-OCT data.

Influence of diabetes mellitus on anterior segment of the eye

Diabetes mellitus (DM) has been emerging as one of the most serious health problems worldwide. Ocular complications of DM are currently one of the major causes of blindness in developed countries, among which diabetic retinopathy is relatively well studied and understood. However, although ocular surface complications of DM are common, diabetic complications of anterior segment of the eye, such as, cornea, conjunctiva, and lacrimal glands, are often overlooked. DM is associated with progressive damage to corneal nerves and epithelial cells, which increases the risk of anterior segment disorders including dry eye disease, corneal erosion, persistent epithelial defects, and even sight-threatening corneal ulcer. In this review, the authors will discuss the association of DM with disorders of anterior segment of the eye. Studies indicating the value of corneal nerve assessment as a sensitive, noninvasive, and repeatable biomarker for diabetic neuropathy will also be introduced. In addition, treatment modalities of anterior segment disorders associated with DM is discussed. The studies introduced in this review suggest that early and periodic screening of the anterior segment of the eye, as well as the retina, is important for the optimal treatment of DM.

Quantitative analysis of pupillometry in isolated third nerve palsy

OBJECTIVES

To objectively assess pupillary involvement according to various etiologies of acquired isolated third nerve palsy using automated pupillometry, and evaluate the efficacy of digital pupillometry in discriminating compressive lesions from microvascular ischemic third nerve palsy.

DESIGN

Retrospective, observational case series.

METHODS

A total of 171 subjects were included in this study, consisting of 60 subjects with presumed microvascular ischemic third nerve palsy, 51 with non-ischemic third nerve palsy, and 60 controls whose pupillary light responses were measured using a dynamic automated pupillometer. Subjects with non-ischemic third nerve palsy were divided into subgroups according to their etiology; inflammatory and compressive groups including tumor and aneurysm. Pupillometry parameters including minimum and maximum pupil diameters, constriction latency and ratio, maximum and average constriction velocities and dilation velocity were noted. The diagnostic ability of pupillometry parameters for discriminating compressive vs microvascular ischemic third nerve palsy was evaluated. The inter-eye difference of the involved eye and the uninvolved fellow eye was calculated to adjust for individual variability.

RESULTS

Among all parameters, reduced pupillary constriction ratio was the most specific parameter for detecting non-ischemic third nerve palsy, as a large inter-eye difference beyond the normative range of controls was found in 0% of ischemic, 20% of inflammatory and 60% of compressive third nerve palsy. With the diagnostic criteria using inter-eye differences of 1) minimum pupil diameter > 0.45 mm, or 2) pupillary constriction ratio < -7.5% compared to the fellow eye, the sensitivity and specificity for diagnosing compressive third nerve palsy were 95% and 88%, respectively. In the compressive group, positive correlations were found between the degree of external ophthalmoplegia and constriction ratio (r = 0.615, p<0.001), average constriction velocity (r = 0.591, p = 0.001) and maximum constriction velocity (r = 0.582, p = 0.001).

CONCLUSIONS

Abnormal pupillary constriction ratio was highly specific for detecting compressive third nerve palsy, although the sensitivity was not high. Digital pupillometry demonstrated relatively good performance for discriminating compressive lesions from microvascular ischemic third nerve palsy.

Obstructive sleep apnoea and increased risk of non-arteritic anterior ischaemic optic neuropathy

BACKGROUND/AIMS

To determine whether the development of non-arteritic anterior ischaemic optic neuropathy (NAION) is increased among patients newly diagnosed with obstructive sleep apnoea (OSA) in a large general population.

METHODS

A 12-year nationwide, population-based, retrospective cohort study including 1 025 340 beneficiaries in the 2002-2013 Korean National Health Insurance Service database was performed. We identified 919 patients newly diagnosed with OSA aged ≥40 years and matched 9190 non-OSA controls using estimated propensity scores in reference to age, sex, demographics, comorbidities and co-medications. We applied Kaplan-Meier curves and Cox proportional hazard models to determine the risk of developing NAION in the OSA group compared with the non-OSA group.

RESULTS

The 10-year incidence probability of NAION was higher in the OSA group (0.92%; 95% CI 0.88 to 0.97) than the non-OSA group (0.42%; 95% CI 0.41 to 0.44, p=0.002, log-rank test). The OSA group was at increased risk of developing NAION compared with the non-OSA group (HR 3.80; 95% CI 1.46 to 9.90) after adjusting for demographics, comorbidities and co-medications.

CONCLUSIONS

Our results suggest that patients with newly diagnosed OSA have an increased risk of NAION, although the absolute risk of NAION is low.

Quantitative analysis of structure-function relationship between ocular motility and superior oblique muscle hypoplasia in unilateral superior oblique palsy

AIMS

To determine the structure-function relationship between the degree of superior oblique (SO) hypoplasia and ocular motility in unilateral SO palsy.

METHODS

A total of 166 patients with unilateral SO palsy were divided into three groups based on their aetiology and high-resolution MRI findings by an in-plane resolution of 0.25 mm: (1) congenital SO palsy and unilateral trochlear nerve agenesis (absent group, n=79), (2) congenital SO palsy and symmetric trochlear nerves on both sides (present group, n=40) and (3) acquired SO palsy (acquired group, n=47) who all had symmetric trochlear nerves on both sides. The degree of SO hypoplasia was defined as the ratio of SO area between the paretic and nonparetic sides (SO_P/N) at the optic nerve-globe junction on MR images. Multivariate analysis was performed to investigate the relationship between SO hypoplasia and ocular motility parameters.

RESULTS

The degree of SO hypoplasia (SO_P/N) showed a weak negative correlation with bilateral head tilt differences in all groups (β=-0.009, p<0.001 in the absent group; β=-0.003, p=0.034 in the present group; β=-0.007, p=0.002 in the acquired group). There was only a weak positive correlation with SO_P/N and hypertropia differences between both gazes in the absent group (β=0.009, p<0.001) and the acquired group (β=0.007, p=0.001). In addition, none of the other ocular motility parameters were related to the degree of SO hypoplasia in all groups.

CONCLUSION

Regardless of the aetiology of unilateral SO palsy, the structure-function relationship of the paretic SO size and ocular motility examination was weak and almost negligible.

Ocular motor cranial nerve palsy and increased risk of stroke in the general population

Purpose

To determine whether ocular motor cranial nerve (CN) palsy raises the risk of subsequent stroke in the general population.

Methods

We investigated the association between ocular motor CN palsy and occurrence of stroke using the National Health Insurance Service-National Sample Cohort database from 2002 to 2013. We included individuals aged ≥ 20 years on January 1^st, 2004, and excluded those having any paralytic strabismus, disorders in binocular movement, diplopia and any cerebrovascular diseases before entering the cohort. Incident ocular motor CN palsy was identified by diagnostic codes for third, fourth, and sixth nerve palsies. To determine the effect of incident ocular motor CN palsy on the occurrence of subsequent stroke, we used time-varying covariate Cox regression models. Model 1 included only incident third, fourth, and sixth nerve palsies as a time-varying covariate. Model 2 included Model 1 and defined demographic information. Model 3 included Model 2, comorbidity, co-medication, and the Charlson index score.

Results

Among 727,689 individuals in the cohort, 1,633 patients developed ocular motor CN palsy and 17,657 patients suffered stroke. Cox regression models showed that development of ocular motor CN palsy was associated with an increased risk of subsequent stroke (hazard ratio [HR] = 4.65; 95% confidence intervals [CIs], 3.74–5.80 in Model 1), and the results were consistent even after adjusting for demographic factors and confounders in Model 2 and 3. Men, older age, and individuals not living in Seoul/Incheon area were associated with an increased risk of stroke, while individuals with higher income were associated with decreased risk of stroke in both Model 2 and 3. Sensitivity analyses using propensity score-based matching produced similar results in all three Models (HR = 1.95; 95% CI, 1.55–2.46 in Model 1, HR = 1.91; 95% CI, 1.52–2.41 in Model 2, and HR = 1.63; 95% CI, 1.29–2.06 in Model 3).

Conclusions

The occurrence of ocular motor CN palsy is a significant risk factor of subsequent stroke even after adjusting for demographic factors and confounders in the general population. Physicians may need to educate patients with ocular motor CN palsy regarding the higher risk of future stroke.

Surgical outcomes of unilateral recession and resection in intermittent exotropia according to forced duction test results

PURPOSE

To compare the surgical outcomes of unilateral lateral rectus recession-medial rectus resection (RR) according to forced duction test (FDT) results with those of conventional RR in intermittent exotropia.

METHODS

A total of 129 patients aged 3 to 10 years with intermittent exotropia who underwent RR between 2006 and 2011 were included. The operator compared the tension of the lateral rectus (LR) between both eyes. When FDT results were asymmetric, RR was performed on the eye with more LR tension. RR was performed on the nondominant eye when FDT results were symmetric. Patients were divided into two groups; one group (n = 64) underwent RR without FDT (RR group) and the other group (n = 65) underwent RR considering FDT results (RR-FDT group). Success, recurrence, reoperation rates and cumulative probabilities of success were evaluated in both groups. Surgical outcome was considered satisfactory if the distance deviation in the primary position was between ≤ 10 PD of exophoria/tropia and ≤ 10 PD of esophoria/tropia. Recurrence was defined as an alignment of > 10 PD of exophoria/tropia, and overcorrection defined as > 10 PD of esophoria/tropia. Reoperation for recurrence was recommended for constant exotropia ≥ 14 PD at distance.

RESULTS

The total follow-up periods were 4.4±2.3 years in the RR group, and 3.9±2.0 years in the RR-FDT group (P = .310). In the RR group, 50 patients (78.1%) were successful, 13 patients (20.3%) had recurrence, and 1 patient (1.6%) had overcorrection at 2 years after surgery. In the RR-FDT group, 58 patients (89.2%) were successful, 5 patients (7.7%) had recurrence, and 2 patients (3.1%) were overcorrected. The recurrence rate at 2 years after operation was significantly lower in the RR-FDT group (P = .045). Recurrence rates during the follow-up period were 5.6% per person-year in the RR group and 2.7% per person-year in the RR-FDT group. Reoperation for recurrence was performed on 7 patients (10.8%) in the RR-FDT group and 16 patients (25.0%) in the RR group (P = .035). Postoperative sensory outcomes were similar between both groups.

CONCLUSIONS

The forced duction test was useful in reducing the risk of recurrence at 2 years after surgery when RR was performed on the eye with more passive tension of the LR. Intraoperative FDT may be considered to choose which eye to operate on when planning RR in intermittent exotropia.

IgG4-related ophthalmic disease involving extraocular muscles: case series

Background

To elucidate the clinical features of strabismus associated with IgG4-related ophthalmic disease (IgG4-ROD).

Case summary

All of the four patients with IgG4-ROD showed marked enlargement of the extraocular muscles, however, two patients showed orthotropia with full ductions and versions. One patient showed a small angle of exotropia and hypertropia of less than 5 prism diopters. One remaining patient showed orthotropia, full ductions and versions despite marked enlargement of the extraocular muscles, then developed hypertropia up to 35 prism diopters with activation of inflammation, which promptly improved after treatment with oral steroids.

Conclusions

IgG4-ROD usually shows normal ocular motility despite extraocular muscle enlargement, which is the key distinguishing feature from other orbital inflammatory diseases. Active flare-up with increased serum IgG4 levels may produce a large angle of eye deviation, but mostly respond well to steroid treatment.