Etiological distribution of isolated oculomotor nerve palsy: analysis of 633 patients and literature review

BACKGROUND AND PURPOSE

The etiological distribution of oculomotor nerve palsy has varied amongst the studies. This study aimed to define the clinical features and underlying etiologies of isolated oculomotor nerve palsy by recruiting patients from all departments in a referral-based university hospital.

METHODS

The medical records of 672 patients who had a confirmed diagnosis of isolated oculomotor nerve palsy at all departments of Seoul National University Bundang Hospital, Seongnam, South Korea, from 2003 to 2020 were reviewed. A proportion of the etiology of isolated oculomotor nerve palsy was also compared with that of patients pooled from the previous studies that were searched on PubMed in May 2022.

RESULTS

The most common etiology was microvascular (n = 168, 26.5%), followed by vascular anomalies (n = 110, 17.4%), neoplastic (n = 86, 13.6%), inflammatory (n = 79, 12.5%), idiopathic (n = 60, 9.5%) and traumatic (n = 53, 8.4%). Neurologists were mainly involved in the management of microvascular and inflammatory oculomotor nerve palsies whilst ophthalmologists mainly participated in the care of idiopathic, neoplastic and traumatic palsies. Neurosurgeons mostly took care of oculomotor nerve palsy due to vascular anomalies.

CONCLUSIONS

The proportion of etiologies of isolated oculomotor nerve palsy may differ according to the specialties involved in the management. The results of previous studies on the etiological distribution of isolated oculomotor nerve palsy should be interpreted with this consideration.

Poor visual prognosis of Asian patients with 3460 mitochondrial DNA mutation in Leber's hereditary optic neuropathy

BACKGROUND

Among the 3 primary mutations of Leber's hereditary optic neuropathy (LHON), the incidence of LHON with a mutation at nucleotide position 3460 is the lowest in Asians. Therefore, information about the clinical manifestations of LHON mutations in Asians with the 3460 mutation is limited.

OBJECTIVE

To determine the clinical manifestations including visual prognosis of Asians with the LHON 3460 mutation.

METHODS

We performed a retrospective study of 5 Korean LHON patients with the 3460 mutation.

RESULTS

All patients were male, and the age of onset for visual impairment varied from 17 to 35 years, with an average of 25.4 ± 7.16 years. Among the 10 affected eyes, only 1 eye of 1 patient showed visual improvement to 20/50 at 2 years after onset. The remaining patients had a visual acuity of worse than 20/200.

CONCLUSION

The visual prognosis of Korean patients with the LHON 3460 mutation was generally poor. Further studies regarding Asian patients with the LHON 3460 mutation are necessary.

Mitochondrial DNA mutations in Korean patients with Leber's hereditary optic neuropathy

In order to explore the spectrum of mitochondrial DNA (mtDNA) mutations in Korean patients with Leber's hereditary optic neuropathy (LHON), we investigated the spectrum of mtDNA mutations in 145 Korean probands confirmed with the diagnosis of LHON. Total genomic DNA was isolated from the peripheral blood leukocytes of the patients with suspected LHON, and mtDNA mutations were identified by direct sequencing. Analysis of mtDNA mutations revealed seven primary LHON mutations including the nucleotide positions (nps) 11778A (101 probands, 69.2%), 14484C (31 probands, 21.2%), 3460A (5 probands, 3.4%), and G3635A, G3733A, C4171A, and G13051A mutations in one proband each. In addition, two provisional mtDNA mutations at nps T3472C, and G13259A were each found in one proband, respectively. Another provisional mtDNA mutation at np T3394C was found in two probands. In conclusion, the spectrum of mtDNA mutations in Korean patients with LHON may differ from other ethnicities, which is characterized by high prevalence of 11778A and 14484C mutations, and a low prevalence of the 3460A mutation.

Risk of central nervous system demyelinating attack or optic neuritis recurrence after pediatric optic neuritis in Korea

PURPOSE

To investigate the rate of development of symptomatic central nervous system (CNS) demyelinating attacks or recurrent optic neuritis (ON) after the first episode of ON and its risk factors for Korean pediatric patients.

METHODS

This multicenter retrospective cohort study included the patients under 18 years of age (n=132) diagnosed with ON without previous or simultaneous CNS demyelinating diseases. We obtained the clinical data including the results of neuro-ophthalmological examinations, magnetic resonance images (MRIs), antibody assays, and laboratory tests. We investigated the chronological course of demyelinating disease with respect to the occurrence of neurological symptoms and/or signs, and calculated the 5-year cumulative probability of CNS demyelinating disease or ON recurrence.  RESULTS: During the follow-up period (63.1±46.7 months), 18 patients had experienced other CNS demyelinating attacks, and the 5-year cumulative probability was 14.0±3.6%. Involvement of the extraorbital optic nerve or optic chiasm and asymptomatic lesions on the brain or spinal MRI at initial presentation were significant predictors for CNS demyelinating attack after the first ON. The 5-year cumulative probability of CNS demyelinating attack was 44.4 ± 24.8% in the AQP4-IgG group, 26.2±11.4% in the MOG-IgG group, and 8.7±5.9% in the double-negative group (P=0.416). Thirty-two patients had experienced a recurrence of ON, and the 5-year cumulative probability was 24.6±4.0%. In the AQP4-IgG group, the 5-year cumulative probability was 83.3±15.2%, which was significantly higher than in the other groups (P<0.001).

CONCLUSIONS

A careful and multidisciplinary approach including brain/spinal imaging and antibody assay can help predict further demyelinating attacks in pediatric ON patients.

Efficacy of 3D-printed eye model to enhance retinoscopy skills

We conducted a prospective study to evaluate the efficacy of simulation-based education using a three-dimensional (3D)-printed schematic eye model in improving the retinoscopy refraction skills of medical students. A schematic eye model was printed using a fused deposition modeling-based 3D printer. Twenty medical students randomized into 3D (n = 10) and control (n = 10) groups received a 1-h lecture on the principles and methods of manifest refraction and were shown how to use the retinoscope and sciascope bars. The 3D group additionally attended a tutorial on the schematic eye. Both groups performed refractive examinations on four eyes of volunteer patients, and the results were recorded as a baseline. Instructor feedback and refraction practice was provided with the 3D group or with control group. To account for subject fatigue, patients spent no more than 8 min on the examination. After a 1-h break to allow for fatigue and familiarity, refraction tests were repeated on four randomly selected eyes of patients. Students' refraction readings were compared with the autorefractor values using a spherical equivalent value and blur strength. All participants measured the time required to complete the refraction test and reported their subjective confidence in the results of each refraction test. Refractive errors before and after training did not differ between the control and 3D groups, with a significant improvement in errors observed in both groups (p = 0.005 and 0.008, respectively). The time to complete refraction before and after training did not differ between the two groups, both of which showed a significant reduction in time (p = 0.005 and 0.028, respectively). Pre- and post-training confidence scores for the accuracy of each refraction on a 10-point Likert scale were not significantly different. However, when comparing score changes between pre- and post-training, only the control group showed a significant increase in confidence (p = 0.005). Tests for the non-inferiority of refractive errors after training indicated that the 3D group was non-inferior to the control group. In conclusion, training in retinoscopy refraction skills using a 3D-printed eye model resulted in significant improvement in accuracy and speed compared to practice with real patients. Except for better confidence in the control group, schematic eye model training was not inferior to practice with real patients.

Deep Learning System Outperforms Clinicians in Identifying Optic Disc Abnormalities

BACKGROUND

The examination of the optic nerve head (optic disc) is mandatory in patients with headache, hypertension, or any neurological symptoms, yet it is rarely or poorly performed in general clinics. We recently developed a brain and optic nerve study with artificial intelligence-deep learning system (BONSAI-DLS) capable of accurately detecting optic disc abnormalities including papilledema (swelling due to elevated intracranial pressure) on digital fundus photographs with a comparable classification performance to expert neuro-ophthalmologists, but its performance compared to first-line clinicians remains unknown.

METHODS

In this international, cross-sectional multicenter study, the DLS, trained on 14,341 fundus photographs, was tested on a retrospectively collected convenience sample of 800 photographs (400 normal optic discs, 201 papilledema and 199 other abnormalities) from 454 patients with a robust ground truth diagnosis provided by the referring expert neuro-ophthalmologists. The areas under the receiver-operating-characteristic curves were calculated for the BONSAI-DLS. Error rates, accuracy, sensitivity, and specificity of the algorithm were compared with those of 30 clinicians with or without ophthalmic training (6 general ophthalmologists, 6 optometrists, 6 neurologists, 6 internists, 6 emergency department [ED] physicians) who graded the same testing set of images.

RESULTS

With an error rate of 15.3%, the DLS outperformed all clinicians (average error rates 24.4%, 24.8%, 38.2%, 44.8%, 47.9% for general ophthalmologists, optometrists, neurologists, internists and ED physicians, respectively) in the overall classification of optic disc appearance. The DLS displayed significantly higher accuracies than 100%, 86.7% and 93.3% of clinicians (n = 30) for the classification of papilledema, normal, and other disc abnormalities, respectively.

CONCLUSIONS

The performance of the BONSAI-DLS to classify optic discs on fundus photographs was superior to that of clinicians with or without ophthalmic training. A trained DLS may offer valuable diagnostic aid to clinicians from various clinical settings for the screening of optic disc abnormalities harboring potentially sight- or life-threatening neurological conditions.

Etiologic Distribution of Isolated Abducens Nerve Palsy: Analysis of 807 Patients and Literature Review

BACKGROUND AND PURPOSE

The etiologies of abducens nerve palsy have shown a large variability among the studies. This study aimed to establish the clinical features and underlying etiologies of isolated abducens nerve palsy by recruiting patients from all departments in a referral-based university hospital.

METHODS

We reviewed the medical records of 807 patients with a confirmed diagnosis of isolated abducens nerve palsy at all departments of Seoul National University Bundang Hospital, Seongnam, Republic of Korea, from 2003 to 2020. We also compared the proportion of etiology with that of the patients pooled from the previous studies.

RESULTS

The most common etiology was microvascular (n = 296, 36.7%), followed by idiopathic (n = 143, 17.7%), neoplastic (n = 115, 14.3%), vascular anomalies (n = 82, 10.2%), inflammatory (n = 76, 9.4%), and traumatic (n = 35, 4.3%). Patients were mostly managed by ophthalmologists (n = 576, 71.4%), followed by neurologists (n = 479, 59.4%), emergency physicians (n = 278, 34.4%), neurosurgeons (n = 191, 23.7%), and others (n = 72, 8.9%). The proportion of etiology significantly differed according to the age and sex of the patients and the specialties involved in the management (p < 0.001). Compared to the pooled data from the previous reports, the current study showed a higher prevalence of microvascular cause but a lower occurrence of traumatic and neoplastic causes.

CONCLUSIONS

The results of previous studies on etiologic distribution of isolated abducens nerve palsy should be interpreted with consideration of the demographic features of patients recruited and the specialties involved.

Diplopia: characteristics and etiologic distribution in a referral-based university hospital

BACKGROUND AND OBJECTIVES

The etiologic distribution and clinical features of diplopia may differ according to the specialties involved in the management. This study aimed to establish the clinical features and underlying etiologies of diplopia by recruiting patients from all departments.

METHODS

We reviewed the medical records of 4127 patients with diplopia as the chief complaint, who had been recruited from all departments at Seoul National University Bundang Hospital, Seongnam, Republic of Korea, from 2003 to 2020.

RESULTS

Diplopia was binocular in 3557 (94.2%) and monocular in 219 (5.8%) patients. The common causes of binocular diplopia included microvascular (n = 516, 14.5%), strokes (n = 412, 11.6%), neoplastic (n = 304, 8.5%), myasthenia gravis (n = 253, 7.1%), traumatic (n = 240, 6.7%), and decompensated phoria (n = 232, 6.5%), and comprised more than a half of the causes. Patients with binocular diplopia were usually managed by neurologists (2549/3557, 71.7%), followed by ophthalmologists (2247/3557, 63.2%), emergency physicians (1528/3557, 43.0%), neurosurgeons (361/3557, 10.1%), and others (271/3557, 7.6%). The etiologies of binocular diplopia differed markedly according to the patients' age and the specialties involved in the management (p < 0.001).

CONCLUSIONS

Given the differences in the etiologic distribution of diplopia according to the patients' age and the specialties involved in the management, the results of previous reports on the characteristics and etiology of diplopia, primarily performed in a single specialty department, should be interpreted with a possible selection bias.

A cross-sectional study of ophthalmologic examination findings in 5385 Koreans presenting with intermittent exotropia

The Korean Intermittent Exotropia Multicenter Study (KIEMS) was a retrospective, cross-sectional and multicenter study for the investigation of intermittent exotropia involved 65 strabismus specialists from 53 institutions in Korea. Purpose of this study was to present ophthalmologic findings of intermittent exotropia from the KIEMS. Consecutive patients with intermittent exotropia of ≥ 8 prism diopters (PD) at distance or near fixation were included. Best-corrected visual acuity, cycloplegic refraction data, angles of deviation at several cardinal positions, ocular dominance, fusion control, oblique muscle function, and binocular sensory outcomes were collected. A total of 5385 participants (2793 females; age 8.2 years) were included. Non-dominant eye was more myopic than the dominant eye (- 0.60 vs. - 0.47 diopters, P < 0.001). Mean exodeviation angles were 23.5 PD at distance and 25.0 PD at near fixation. Basic type (86.2%) was the most, followed by convergence insufficiency (9.4%) and divergence excess (4.4%) types. Alternating ocular dominance and good fusion control were more common at near than at distance fixation. Good stereopsis at 40 cm was observed in 49.3% in Titmus stereo test (≤ 60 arcsec) and in 71.0% in Randot stereo test (≤ 63 arcsec). Intermittent exotropia was mostly diagnosed in childhood and patients with the condition showed relatively good binocular functions. This study may provide objective findings of intermittent exotropia in a most reliable way, given that the study included a large study population and investigated comprehensive ophthalmology examinations.

How to Better Treat Patients with Intermittent Exotropia: A Review of Surgical Treatment of Intermittent Exotropia

Intermittent exotropia (X(T)) is the most common form of strabismus, especially in Asians. Treatment of X(T) includes occlusion, overminus lens, and surgery, of which, surgery is the mainstay of treatment. Commonly performed surgical procedures for X(T) are bilateral lateral rectus muscle recession or unilateral lateral rectus recession with medial rectus resection; however, it is unclear which of the two surgeries is more effective. The purpose of this review is to provide an insight on the surgical treatment of X(T). Randomized controlled trials, comparative observational studies, and case series with a large number of patients as well as a long follow-up period of over a year were included.

Etiologic Distribution of Isolated Trochlear Palsy: Analysis of 1,020 Patients and Literature Review

BACKGROUND AND PURPOSE

Trochlear palsy is the most common cause of vertical diplopia. The etiologies of trochlear palsy have shown a large discrepancy among the studies. This study aimed to establish the clinical features and underlying etiologies of isolated trochlear palsy by recruiting the patients from all departments in a referral-based university hospital.

METHODS

We reviewed the medical records of 1,258 patients who had a confirmed diagnosis of isolated trochlear palsy at all departments of Seoul National University Bundang Hospital, Seongnam, South Korea, from 2003 to 2020. We also compared the proportion of etiology with that of the patients pooled from the previous studies.

RESULTS

The most common etiology was congenital (n = 330, 32.4%), followed by idiopathic (n = 256, 25.1%), microvascular (n = 212, 20.8%), and traumatic (n = 145, 14.2%). These four etiologies explained 92.5% of isolated trochlear palsy. Patients were mostly managed by ophthalmologists (n = 841, 82.5%), followed by neurologists (n = 380, 37.3%), emergency physicians (n = 197, 19.3%), neurosurgeons (n = 75, 7.4%), and others (n = 18, 1.8%). The etiologic distribution of isolated trochlear palsy in the current study did not differ from that of 2,664 patients pooled from the previous studies.

CONCLUSIONS

The proportion of etiologies of isolated trochlear palsy differs according to the age ranges of the patients and specialties involved in the management. The etiologic distribution of isolated trochlear palsy in the current study was comparable to the pooled result of previous reports.

Factors associated with seropositivity to Aino virus among sheep and goats in South Korea

Aino virus infection is responsible for epizootic and/or sporadic outbreaks of abortions, stillbirths and premature delivery among pregnant ruminants. The epizootiology of Aino virus infection is poorly defined in South Korea, therefore our aim was to assess its seroprevalence among sheep and goats. We also wanted to evaluate management and regional risk factors that might influence the frequency of infection. Between 2012 and 2013, 26 of 331 flocks (7.9%) and 139 of 915 heads (15.2%) were found serologically positive. In 2018, when samples were again collected in the same regions, 35 of 308 flocks (11.4%) and 89 of 735 heads (12.1%) showed serum-neutralising antibodies against Aino virus. Our results revealed that the age class and history of reproductive problems in the flocks are connected to an increased risk of being positive. The management risk factor attributes showed that preventive measures, such as the routine application of insecticide in farms, decreased the odds for seropositivity to Aino virus (OR = 0.453, P = 0.001). We observed a significant difference in the individual likelihood of being positive in the southern and western provinces with respect to that in the northern and eastern provinces, respectively (OR = 2.199, P < 0.001 and OR = 2.177, P < 0.001). The results of this study may serve as a basis for future epizootic studies on Aino virus infection in South Korea.

Long term surgical outcomes of unilateral recession-resection versus bilateral lateral rectus recession in basic-type intermittent exotropia in children

The long-term results of surgical treatment of intermittent exotropia (X(T)) according to the type of surgery are controversial. We conducted a retrospective cohort study to compare the long-term results between unilateral recession-resection (RR) and bilateral lateral rectus recession (BLR) with an average follow-up of 9.5 years in children with basic-type X(T). Patients with basic-type X(T), who underwent RR (RR group) or BLR (BLR group) and were followed-up for more than 5 years postoperatively, were analyzed. Of the 560 patients, 363 patients received BLR and 197 patients underwent RR. There was no significant difference in the success rates between the two groups until postoperative 3 years. At an average of 9.5 ± 2.6 years after surgery, the success rate of the RR group was significantly higher than that of the BLR group starting from the fourth post-operative year until the last follow-up examination (64.5% vs 43.3%, P < 0.001). By multivariate analysis, preoperative hyperopia of more than + 2.00 diopters, younger age of onset, younger age at surgery, larger exodeviation at near than at distance of > 5 prism diopters, and the type of surgery (BLR) were risk factors of recurrence. In conclusion, RR was more successful than BLR with a lower recurrence rate in the long-term follow-up of patients with basic-type X(T).

Comparison of Optic Nerve Head Microvasculature Between Normal-Tension Glaucoma and Nonarteritic Anterior Ischemic Optic Neuropathy

Purpose

To compare the microvasculature of the optic nerve head (ONH) and peripapillary tissues in eyes with normal-tension glaucoma (NTG) and nonarteritic anterior ischemic optic neuropathy (NAION) using optical coherence tomography angiography (OCTA).

Methods

Thirty-eight eyes with treatment-naïve NTG, 38 eyes with NAION matched for retinal nerve fiber layer (RNFL) thickness in each superior and inferior quadrant, and 38 healthy eyes matched by age were included. ONH and peripapillary retinal microvasculature was evaluated in en face images obtained using OCTA. Vessel density (VD) was calculated as the percent area occupied by vessels in the measured region in each layer segmented into the prelaminar tissue (PLT), lamina cribrosa (LC), and peripapillary retina (PR).

Results

VDs in the PLT and LC were lower in NTG eyes than in both NAION and healthy eyes (P ≤ 0.008), and did not differ between the NAION and healthy eyes. VDs in the PR did not differ between the NTG and NAION eyes. In intersectoral comparisons, VDs in the PLT (P = 0.030) and LC (P = 0.028) were lower in the affected than in the unaffected sector of eyes with NTG, but the differences did not occur in eyes with NAION. VD in the PR was lower in the affected than in the unaffected sector in both NTG and NAION eyes (both P < 0.001).

Conclusions

Despite similar degrees of RNFL loss and VD decreases in the PR, VDs in the ONH differed between eyes with NTG and NAION, indicating different mechanisms of vascular impairment and ONH damage in each condition.

Optic Perineuritis as a Presenting Sign of Sarcoidosis

Purpose: To report a rare case of optic perineuritis as the presenting sign of sarcoidosis. Case summary: A 57-year-old man presented with decreased visual acuity and pain with extraocular movement in his left eye starting 2 weeks earlier. He had a history of asymptomatic optic perineuritis in that eye 18 months previously, which had improved after 1 month on oral prednisolone. His best corrected visual acuity had decreased to 20/50 and he also had relative afferent pupillary defect and color vision defects in the left eye. Slit lamp examination results were normal. There were no inflammatory reactions in the anterior chamber or vitreous. Fundoscopy showed optic disc edema. Orbital magnetic resonance imaging showed diffuse enhancement surrounding the left optic nerve. The serum levels of eosinophil cationic protein and angiotensin- converting enzyme were markedly increased. A chest radiograph showed bilateral hilar lymph node enlargement. A biopsy via endobronchial ultrasound-guided transbronchial needle aspiration revealed multifocal non-caseating granulomas. Acid fast bacilli stain showed no evidence of tuberculosis. Based on these findings, he was diagnosed with sarcoidosis. After treatment with high-dose intravenous methylprednisolone and subsequent tapering with oral prednisolone for 6 months, the visual acuity improved. Conclusions: Optic perineuritis can be the initial sign of sarcoidosis. Therefore, sarcoidosis should be considered in the differential diagnosis of optic perineuritis.

Dilute pilocarpine test for diagnosis of Adie's tonic pupil

We have compared the diagnostic ability of different concentrations of 0.125% and 0.0625% dilute pilocarpine for detecting denervation supersensitivity in unilateral Adie's tonic pupil. This retrospective, observational, case-control study involved 117 subjects, consisting of 56 patients with unilateral Adie's tonic pupil and 61 controls with other causes of unilateral dilated pupils. Subjects underwent the dilute pilocarpine test with one of the two concentrations, 0.125% or 0.0625%. Pupillary light reflex was recorded with a dynamic pupillometer at baseline and at 30-40 min after instilling one of the two concentrations of dilute pilocarpine. Diagnostic accuracy of two different concentrations of the dilute pilocarpine test, 0.125% group versus 0.0625% group, were compared by area under the receiver operating characteristic curve (AUC). Diagnostic ability of the dilute pilocarpine test for detecting denervation supersensitivity in unilateral Adie's tonic pupil was significantly better in the 0.0625% group than in the 0.125% group (AUC = 0.954 vs. 0.840, respectively, P = 0.047). In the 0.0625% group, the change in maximal pupil diameter of ≥ 0.5 mm after topical pilocarpine instillation showed 100% sensitivity and 82.8% specificity for detecting Adie's tonic pupil. This study confirmed that pupillary constriction with 0.0625% pilocarpine is better than 0.125% pilocarpine for detecting denervation supersensitivity in Adie's tonic pupil. Digital pupillometry is a reliable method for assessing denervation supersensitivity in Adie's tonic pupil.

Change in the eye position under general anesthesia in children with intermittent exotropia

PURPOSE

To evaluate the eye position in subjects with intermittent exotropia and normal subjects under general anesthesia (GA) using the strabismus photo analyzer.

METHODS

This retrospective case-control study included 78 subjects with intermittent exotropia and 25 normal control subjects who underwent epiblepharon surgery. Eye position under GA was assessed using the strabismus photo analyzer, based on eye models generated from corneal lights and limbus in pre- and post-anesthesia images. Eye positions under GA in the control and intermittent exotropia groups were compared. Preoperative angle of deviation was also compared with amount of change in eye position under GA in the intermittent exotropia group.

RESULTS

Eye position under GA was more divergent in subjects with intermittent exotropia than in controls (P = 0.008). The amount of change in eye position under GA was correlated with the preoperative angle of deviation (r² = 0.47; P < 0.001). In small preoperative exodeviations, the change in eye position was primarily more divergent, whereas in large exodeviations, a convergent tendency-less exotropic compared with the preoperative angle of exodeviation-was observed.

CONCLUSIONS

In subjects with small preoperative exodeviations, there was a tendency for eye position to become more divergent after GA; in those with large exodeviations, there was less exotropia after GA.

Differentiation of Nonarteritic Anterior Ischemic Optic Neuropathy from Normal Tension Glaucoma by Comparison of the Lamina Cribrosa

Purpose

To compare lamina cribrosa (LC) morphology between eyes with nonarteritic anterior ischemic optic neuropathy (NAION) and eyes with normal tension glaucoma (NTG) in the Korean population.

Methods

This retrospective study included 48 eyes with NAION, 48 eyes with NTG, and 48 healthy control eyes matched by age, intraocular pressure, axial length, and optic disc area. Eyes with NAION and NTG were also matched by retinal nerve fiber layer (RNFL) thickness in the affected sector. Optic nerve heads were scanned using enhanced depth imaging spectral-domain optical coherence tomography. LC depth (LCD) and the LC curvature index (LCCI) were measured at seven locations spaced equidistantly across the vertical optic disc diameter. LCD and the LCCI were compared in the three groups.

Results

RNFL thicknesses of the matched affected sectors did not differ between the NAION and NTG groups (P = 0.347). LCD and the LCCI were significantly larger in the NTG group than in the NAION and healthy control groups at all seven planes (P < 0.001 each), but were comparable in the NAION and healthy control groups. The LCCI was larger in the affected than in the unaffected sector of NTG eyes (P = 0.010) but did not differ in NAION eyes (P = 1.000). LCD did not differ between affected and unaffected sectors in either NAION (P = 0.600) or NTG (P = 0.098) eyes.

Conclusions

LC morphology differed in eyes with NAION and NTG, despite a similar degree of RNFL damage. Evaluation of LC morphology may help to understand the distinctive pathophysiology of NAION and to differentiate NAION from NTG eyes.

Epidemiological Assessment of Risk Factors Associated with Bovine Ephemeral Fever Virus Exposure among Sheep and Goats in South Korea

Background: Bovine ephemeral fever virus (BEFV) is an arthropod-borne virus classified as a type species of the genus Ephemerovirus, family Rhabdoviridae. BEFV is the causative agent of bovine ephemeral fever (BEF), a non-contagious disease of acute febrile clinical signs in cattle and water buffalo. Some species might act as reservoir hosts, and antibodies to BEFV have also been found in asymptomatic sheep, goats, pigs, and many wild animals. This study aimed to conduct a retrospective cross-sectional serological screening in South Korea to address BEFV seroprevalence and identify risk factors for becoming seropositive for the virus in sheep and goats. Materials, Methods & Results: The apparent prevalence rates were considered to be the animal-level prevalence, defined as the proportion of serum neutralization test (SNT)-positive animals out of the total number of animals tested in the study area, and flock prevalence was defined as the proportion of SNT-positive flocks out of the total number of tested flocks in the area. A flock was classified as positive if at least one animal was SNT-positive. At the national level in 2011, 28 of 177 flocks (15.8%; 95% CI, 11.2−21.9%) and 71 of 498 heads (14.3%, 95% CI: 11.5-17.6%) that were analyzed showed serum neutralizing antibodies against BEFV. Our results revealed that age class, vector control, and geographic location affected seroprevalence to differing extents. In the univariate analysis, older age was a significant risk factor (OR, 2.327; 95% CI, 1.147-4.721; P = 0.017 in adults). The management risk factor attributes showed that preventive measures, such as routine application of insecticides in farms, decreased the odds of seropositivity for BEFV (OR, 0.514; 95% CI, 0.267-0.991; P = 0.044). Vector control was a significant protective factor, while animal species, flock size, and flock structure were not significantly associated. Differences in seroprevalence between variations in the presence of ruminant farms, lakes, or rice paddies within a 1-km radius or type of land use were not statistically significant (P > 0.05). We observed a significant difference in the individual likelihood of being positive in the southern provinces with respect to that in the northern provinces (OR, 2.166; 95% CI, 1.228-3.824; P = 0.007). Differences in seroprevalence between variations in the eastern and western regions were not statistically significant (P > 0.05). The retrospective study results showed that the virus was widely distributed in sheep and goats in South Korea, with seropositive rates ranging from 7.8% to 19.7% between 2003 and 2008.Discussion: This is the first report of circulating antibodies against BEFV in sheep and goats in South Korea. The serological prevalence of BEFV infection in sheep and goats was significantly different between different age cohorts, vector control, and geographical locations: it was higher in the older group and the southern and western regions of South Korea. Determination of seropositivity rates often leads to an understanding of virus circulation dynamics and is useful in the formulation of disease control measures. Our results demonstrated that vector control was a significant protective factor; therefore, the summer control of vectors could be better implemented in provinces with elevated seropositivity rates. The results of this seroprevalence study may serve as a basis for future epidemiological studies on BEFV infection in South Korea.

Pupillary light reflex in ethambutol-induced optic neuropathy

We evaluated changes in the pupillary light reflex (PLR) of ethambutol (EMB)-induced optic neuropathy and analyzed the correlations between PLR parameters and other structural changes in EMB-induced optic neuropathy. This retrospective, observational, case–control study involved thirty-two eyes of 17 patients with EMB-induced optic neuropathy (EON group), sixty eyes of 60 patients without EMB-induced optic neuropathy (non-EON group) while taking ethambutol, and forty-five eyes of 45 normal controls. PLR was measured by digital pupillometry. The clinical characteristics, optical coherence tomography measurements and PLR parameters including pupil diameter, constriction latency, constriction ratio/velocity, and dilation velocity were noted. The differences in PLR measurements were compared among the three groups. Correlations between PLR parameters and other structural parameters in EMB-induced optic neuropathy were evaluated. The pupillary constriction ratio, constriction and dilation velocities were significantly reduced in the EON group compared to the non-EON group and controls (all P < 0.05). In EMB-induced optic neuropathy, average outer macular ganglion cell layer (mGCL) thickness showed a significant correlation with the pupillary constriction ratio (ß = 4.14, P = 0.003) and maximal constriction velocity (ß = 1.08, P < 0.001). This study confirmed that pupillary constriction and dilation velocities were significantly decreased in patients with EMB-induced optic neuropathy, compared to normal controls. Digital pupillometry may be a useful tool in the evaluation of EMB-induced optic neuropathy.

Botulinum toxin injection without electromyographic guidance in consecutive esotropia

Purpose

To investigate the efficacy of botulinum toxin injection without electromyographic guidance for the treatment of consecutive esotropia.

Methods

A retrospective study was performed on 49 subjects with consecutive esotropia who received botulinum toxin injection in the medial rectus muscles without the use of electromyographic guidance. Treatment was considered successful if the final ocular alignment was orthotropic or esodeviation was ≤10 prism diopters (PD) during distant fixation.

Results

The mean age was 15.2 ± 8.3 years. The mean esodeviation before injection was 21.8 ± 9.1 PD at distance and 21.3 ± 8.3 PD at near. The mean number of injections per patient was 1.3 ± 0.7, and 46 patients (93.9%) received two or fewer injections. At 6 months after the final injection, the mean angle of esodeviation was 7.3 ± 6.0 PD at distance and 7.5 ± 6.6 PD at near (all p<0.001), and 69.4% showed successful alignment. By multivariate analysis, an initial postoperative esodeviation of ≤18 PD at one month after exotropia surgery was considered to be a predictive factor for successful botulinum toxin injection (P = 0.007). Vertical deviation and/or ptosis occurred in 4 patients (8.2%) at two weeks after injection, which all resolved within three months. There was no recurrence of exotropia up to the final follow-up examination.

Conclusion

Botulinum toxin injection without electromyographic guidance is safe and effective in the treatment of consecutive esotropia without causing recurrent exotropia. Successful botulinum toxin injection is likely in patients with an initial postoperative esodeviation of 18PD or less at one month after exotropia surgery.

Ocular coloboma combined with cleft lip and palate: a case report

Background

Ocular coloboma is an excavation of ocular structures that occurs due to abnormal fusion of the embryonic optic fissure. Further, cleft lip/palate (CL/P), a congenital midline abnormality, is caused by a defect in the fusion of the frontonasal, maxillary, and mandibular prominences. No study has reported the association between these two phenotypes in the absence of other systemic abnormalities. We present a case of ocular coloboma along with CL/P and without other neurological abnormalities.

Case presentation

A 5-year-old Asian boy presented with decreased visual acuity in his right eye. Physical examination revealed no abnormal findings except CL/P, which was surgically corrected at the age of 9 months. Best-corrected visual acuity was 20/60 in the right eye and 20/25 in the left eye. Anterior segment examination revealed iris coloboma in the inferior quadrant of his right eye as well as a large inferonasal optic disc and chorioretinal coloboma in the same eye. He was prescribed glasses based on his cycloplegic refractive errors and part-time occlusion of the left eye was recommended. After 3 months, best-corrected visual acuity improved to 20/30 in the right eye.

Conclusion

The association of ocular coloboma should be kept in mind when encountering a patient with CL/P without other neurological or systemic abnormalities.

Effect of Ultra-high-definition Television on Ocular Surface and Fatigue

PURPOSE

To investigate the effects of watching ultra-high-definition television (UHD TV) on subjective ocular fatigue and objective ocular surface indices.

METHODS

A total of 76 volunteers were recruited for this study. Subjects watched UHD TV for 10 minutes at a viewing distance of 110 cm. Best-corrected visual acuity, refractive errors, tear break-up time, corneal staining grading, conjunctival redness grading by slit-lamp examination, tear meniscus measurement by anterior segment optical coherence tomography, and ocular symptom scores were obtained before and immediately after watching UHD TV. Subgroup analyses were conducted according to participant age (old age group &gt;50 years vs. young age group ≤50 years) and dry-eye syndrome (presence vs. absence). The relationship between subjective and objective indices was evaluated.

RESULTS

The mean age of subjects was 39.6 ± 12.4 years. Watching UHD TV induced a decrease in tear break-up time in the non-dry-eye group (p &lt; 0.001) but not in the dry-eye group (p = 0.726). Corneal staining grades increased in all subgroups, and the changes were particularly larger in the older group (p = 0.038). The increase in ocular symptom scores was larger in the dry-eye group (p = 0.08) and in the older group (p = 0.016). The decrease in tear break-up time and ocular symptom scores after watching UHD TV was significantly correlated with tear break-up time.

CONCLUSIONS

Tear break-up time significantly decreased in non-dry-eye subjects after watching UHD TV. Subjective ocular discomfort increased significantly in subjects over the age of 50 and in participants with dry-eye syndrome.

Comparison of Lamina Cribrosa Morphology in Normal Tension Glaucoma and Autosomal-Dominant Optic Atrophy

Purpose

To compare lamina cribrosa (LC) morphology in patients with normal tension glaucoma (NTG) and autosomal-dominant optic atrophy (ADOA).

Methods

This cross-sectional study matched 24 patients diagnosed with ADOA (24 eyes) by age and retinal nerve fiber layer thickness with 48 patients diagnosed with NTG (48 eyes) by age with 48 healthy controls (48 eyes). Optic nerve heads were scanned by enhanced-depth imaging (EDI) optical coherence tomography (OCT). The LC curvature index (LCCI) and LC depth (LCD) on B-scan images obtained using EDI-OCT were measured at seven locations spaced equidistantly across the vertical optic disc diameter and compared among the NTG, ADOA, and control groups.

Results

Mean LCCI and LCD were significantly greater in NTG than in ADOA and healthy eyes (P < 0.001 each) but did not differ significantly in ADOA and healthy eyes.

Conclusions

NTG eyes have a more posteriorly curved and deeper LC than ADOA and healthy eyes. This finding provides insight into the role of LC morphology in NTG and provides a clinical clue to distinguish between NTG and ADOA.

Optic Disc Classification by Deep Learning versus Expert Neuro-Ophthalmologists

OBJECTIVE

To compare the diagnostic performance of an artificial intelligence deep learning system with that of expert neuro-ophthalmologists in classifying optic disc appearance.

METHODS

The deep learning system was previously trained and validated on 14,341 ocular fundus photographs from 19 international centers. The performance of the system was evaluated on 800 new fundus photographs (400 normal optic discs, 201 papilledema [disc edema from elevated intracranial pressure], 199 other optic disc abnormalities) and compared with that of 2 expert neuro-ophthalmologists who independently reviewed the same randomly presented images without clinical information. Area under the receiver operating characteristic curve, accuracy, sensitivity, and specificity were calculated.

RESULTS

The system correctly classified 678 of 800 (84.7%) photographs, compared with 675 of 800 (84.4%) for Expert 1 and 641 of 800 (80.1%) for Expert 2. The system yielded areas under the receiver operating characteristic curve of 0.97 (95% confidence interval [CI] = 0.96-0.98), 0.96 (95% CI = 0.94-0.97), and 0.89 (95% CI = 0.87-0.92) for the detection of normal discs, papilledema, and other disc abnormalities, respectively. The accuracy, sensitivity, and specificity of the system's classification of optic discs were similar to or better than the 2 experts. Intergrader agreement at the eye level was 0.71 (95% CI = 0.67-0.76) between Expert 1 and Expert 2, 0.72 (95% CI = 0.68-0.76) between the system and Expert 1, and 0.65 (95% CI = 0.61-0.70) between the system and Expert 2.

INTERPRETATION

The performance of this deep learning system at classifying optic disc abnormalities was at least as good as 2 expert neuro-ophthalmologists. Future prospective studies are needed to validate this system as a diagnostic aid in relevant clinical settings. ANN NEUROL 2020;88:785-795.

Efficacy for Differentiating Nonglaucomatous Versus Glaucomatous Optic Neuropathy Using Deep Learning Systems

PURPOSE

We sought to assess the performance of deep learning approaches for differentiating nonglaucomatous optic neuropathy with disc pallor (NGON) vs glaucomatous optic neuropathy (GON) on color fundus photographs by the use of image recognition.

DESIGN

Development of an Artificial Intelligence Classification algorithm.

METHODS

This single-institution analysis included 3815 fundus images from the picture archiving and communication system of Seoul National University Bundang Hospital consisting of 2883 normal optic disc images, 446 NGON images, and 486 GON images. The presence of NGON and GON was interpreted by 2 expert neuro-ophthalmologists and had corroborated evidence on visual field testing and optical coherence tomography. Images were preprocessed in size and color enhancement before input. We applied the convolutional neural network (CNN) of ResNet-50 architecture. The area under the precision-recall curve (average precision) was evaluated for the efficacy of deep learning algorithms to assess the performance of classifying NGON and GON.

RESULTS

The diagnostic accuracy of the ResNet-50 model to detect GON among NGON images showed a sensitivity of 93.4% and specificity of 81.8%. The area under the precision-recall curve for differentiating NGON vs GON showed an average precision value of 0.874. False positive cases were found with extensive areas of peripapillary atrophy and tilted optic discs.

CONCLUSION

Artificial intelligence-based deep learning algorithms for detecting optic disc diseases showed excellent performance in differentiating NGON and GON on color fundus photographs, necessitating further research for clinical application.

Long-term surgical outcomes of preoperative prism adaptation in patients with partially accommodative esotropia

BACKGROUND

To determine the long-term surgical outcomes of preoperative prism adaptation test (PAT) in patients with partially accommodative esotropia.

METHODS

PAT was performed for the remaining esotropia after full correction of hyperopia. Prism adaptation (PA) responders were defined as patients with stable esodeviation between 0 and 8 prism diopters (PD) while developing sensory fusion throughout the prism adaptation period. Surgical success was defined as a deviation within 8 PD of both the far and near deviation angles at the last follow-up examination.

RESULTS

Of the 102 patients, 43 (42.2%) were PA responders, and 59 were PA non-responders (57.8%). After a mean follow-up duration of 6 years after surgery, the surgical success rate was significantly higher in PA responders (76.7% vs. 54.2%, p = 0.023). By multivariate analysis, good stereoacuity at near before surgery significantly correlated with successful outcomes after surgery (p = 0.001, β = 4.466). The risk factors of undercorrection were preoperative esotropia >35 PD (OR 3.067, p = 0.041), and preoperative hyperopia >+5.25 diopters (OR 3.099, p = 0.049). Among undercorrected patients, the annual decrease of esodeviation was significantly greater in PA responders (p = 0.043).

CONCLUSIONS

PA responders showed a better long-term success rate than in PA nonresponders. Patients with high hyperopia and large esotropia had a higher risk of undercorrection. Undercorrected patients eventually achieved good motor outcome with postoperative prism correction if they were PA responders before surgery.

Prognostic value of macular ganglion cell layer thickness for visual outcome in parasellar tumors

PURPOSE

Optic nerve compression by mass lesions at the optic chiasm leads to loss of visual function which can be recovered after decompression surgery. In this study, we evaluated the prognostic ability of macular ganglion cell layer (mGCL) thickness measured with spectral-domain optical coherence tomography (SD-OCT) for predicting postoperative visual outcome of compressive optic neuropathy (CON) related to parasellar tumors.

METHODS

This observational cohort study used data from the Department of Neurosurgery and Ophthalmology, Seoul National University Bundang Hospital between 2013 and 2018. Seventy-nine eyes from 79 patients with CON due to parasellar tumors who underwent surgery were included. Patients were divided into either a visual recovery group or a non-recovery group according to the degree of postoperative visual field (VF) impairment. SD-OCT scanning with automated segmentation was performed to measure the circumpapillary retinal nerve fiber layer (cpRNFL) and the mGCL thickness in the nine macular subfields as defined by the ETDRS and 8 × 8 posterior pole grid. Correlations between preoperative cpRNFL thickness, mGCL thickness and postoperative VF sensitivity were assessed. The prognostic ability of mGCL thickness for predicting visual recovery after surgical decompression in each ETDRS subfield and posterior pole grid quadrant was evaluated.

RESULTS

The central inferonasal and superonasal quadrant mGCL thicknesses measured by the 8 × 8 posterior pole grid showed the best predictability of postoperative visual outcome (AUROC = 0.963 and 0.953, respectively), which was superior to the prognostic power of the average cpRNFL. The central inferonasal quadrant mGCL thickness significantly correlated with the superotemporal quadrant VF sensitivity (R² = 0.589).

CONCLUSIONS

The mGCL thickness in the central nasal quadrants measured by SD-OCT is an excellent predictor of visual recovery after chiasmal decompression.

Bilateral Fundus Excyclotorsion in Unilateral Superior Oblique Palsy Confirmed by MR Imaging

Purpose: To determine whether bilateral fundus excyclotorsion is helpful in distinguishing bilateral superior oblique palsy (SOP) from unilateral SOP by investigating bilateral fundus excyclotorsion in unilateral SOP and comparing the features with bilateral SOP using fundus photographs. Methods: This retrospective cohort study included a total of 212 subjects who were diagnosed with unilateral SOP with hypoplasia of a single superior oblique (SO) muscle and 7 subjects with clinically diagnosed bilateral SOP. Fundus excyclotorsion measured by modified fovea–disc angles and inter-eye differences in cyclotorsion angles (the difference in fundus excyclotorsion angles: paretic eye or hypertropic eye in primary gaze–fellow eye), and subjective cyclotorsion were compared between groups of unilateral SOP with bilateral fundus excyclotorsion (SOP_BE) and bilateral SOP. Results: Bilateral fundus excyclotorsion was found in 18 out of 212 patients (8.5%) in the unilateral SOP group, and 7 out of 7 patients (100%) in the bilateral SOP group. Among the 25 patients with bilateral fundus excyclotorsion, the mean angle of excyclotorsion (5.7° ± 4.7° vs. 7.6° ± 4.3°, p = 0.125) and the inter-eye differences (0.7° ± 3.6° vs. 0.5° ± 5.8°, p = 0.615) were not significantly different between the unilateral SOP_BE and bilateral SOP groups. The degree of subjective excyclotorsion was significantly larger in the bilateral SOP group compared with the unilateral SOP_BE group (16.0 ± 5.5 vs. 4.6 ± 4.3, p = 0.002). Conclusion: Bilateral fundus excyclotorsion was demonstrated not only in bilateral SOP, but also in unilateral SOP at a rate of 8.5%. Bilateral fundus excyclotorsion alone did not prove to be a specific sign in distinguishing bilateral SOP from unilateral SOP.

Glaucoma-like Parapapillary Choroidal Microvasculature Dropout in Patients with Compressive Optic Neuropathy

PURPOSE

To characterize peripapillary choroidal microvasculature dropout (MvD) in patients with compressive optic neuropathy (CON) as compared with those with open-angle glaucoma (OAG) using OCT angiography (OCTA).

DESIGN

Cross-sectional, observational study.

PARTICIPANTS

Eighty-eight eyes of 44 patients with CON; 88 eyes of 88 patients with OAG matched by age, spherical error, and OCT-determined retinal nerve fiber layer thickness (RNFLT); and 88 eyes of 44 control participants matched by age and spherical error.

METHODS

Peripapillary microvasculature was evaluated, and peripapillary vessel density was measured in en face images segmented into inner-retinal and choroidal layers using swept-source OCTA. An MvD was defined as a focal sectoral capillary dropout with no visible microvascular network in the choroidal layer.

MAIN OUTCOME MEASURES

Comparative characteristics of MvD in eyes with CON and OAG.

RESULTS

Microvasculature dropout was observed in 30 eyes (34.1%) of 22 patients (50.0%) with CON, and in 48 eyes of 48 patients (54.5%) with OAG (P = 0.011). All MvDs in the CON group were located in the temporal parapapillary sector, whereas MvDs in the OAG group were located in the temporal-inferior (n = 36) and temporal-superior (n = 4) sectors. At their locations, MvDs in the CON group were accompanied by significant reductions in retinal vessel density and RNFLT, but this was not observed in the OAG group. The presence of MvD was associated significantly with female gender (P = 0.020) and thinner global retinal nerve fiber layer (P = 0.006) in the CON group, but not in the OAG group.

CONCLUSIONS

OCT angiography of the peripapillary area showed retinal and choroidal microvasculature impairment in patients with both CON and OAG. However, the features and associated characteristics of MvD differed between these groups, suggesting that the pathogenesis of peripapillary microvascular impairment may be diverse.

The outcomes of conservatively observed asymptomatic nonfunctioning pituitary adenomas with optic nerve compression

OBJECTIVE

The authors investigated the natural history of asymptomatic nonfunctioning pituitary adenomas (NFPAs) with optic nerve compression.

METHODS

This study retrospectively analyzed the natural history of asymptomatic NFPAs with documented optic nerve compression on MRI diagnosed between 2000 and 2016 from 2 institutions. The patients were followed up with regular endocrinological, ophthalmological, and radiological evaluations, and the endpoint was new endocrinopathy or neurological deficits.

RESULTS

The study comprised 81 patients. The median age at diagnosis was 58.0 years and the follow-up duration was 60.0 months. As the denominator of overall pituitary patients, 2604 patients were treated with surgery after diagnosis at the 2 institutions during the same period. The mean initial and last measured values for tumor diameter were 23.7 ± 8.9 mm and 26.2 ± 11.4 mm, respectively (mean ± SD). Tumor growth was observed in 51 (63.0%) patients; however, visual deterioration was observed in 14 (17.3%) patients. Ten (12.3%) patients experienced endocrine deterioration. Fourteen (17.3%) patients underwent surgery for either visual deterioration (in 12 patients) or endocrine dysfunction (in 2 patients). After surgery, all patients experienced improvements in visual or hormonal function. The actuarial rates of treatment-free survival at 2, 3, and 5 years were 96.1%, 93.2%, and 85.6%, respectively. In the multivariate analysis, initial cavernous sinus invasion (HR 4.985, 95% CI 1.597-15.56; p = 0.006) was the only independent risk factor for eventual treatment.

CONCLUSIONS

The neuroendocrinological deteriorations were not frequent and could be recovered by surgery with early detection on regular follow-up in asymptomatic NFPAs with documented optic nerve compression on MRI. Therefore, conservative management could be an acceptable strategy for these tumors. Careful follow-up is required for tumors with cavernous sinus invasion.

Morphologic Features of Buried Optic Disc Drusen on En Face Optical Coherence Tomography and Optical Coherence Tomography Angiography

PURPOSE

To evaluate and compare the morphologic characteristics of buried optic disc drusen (ODD) and optic disc edema (ODE) by using en face optical coherence tomography (OCT) and OCT angiography (OCTA).

DESIGN

Retrospective, cross-sectional study.

METHODS

We reviewed the medical records of 61 patients (92 eyes) with buried ODD, 45 patients (62 eyes) with ODE, and 42 normal-appearing fellow eyes examined at 1 referral center between November 1, 2017 and April 30, 2019. Characteristic en face OCT and OCTA findings of buried ODD compared to those of ODE and normal optic discs were investigated.

RESULTS

On en face OCT, all buried ODD were visualized as hyperreflective kidney-shaped masses well demarcated from the optic nerve axons, whereas ODE was visualized as ill-defined boundaries confluent with the retinal nerve fibers. On OCTA, 25.0% of the eyes with buried ODD showed a C-shaped vessel density decrease in the nasal radial peripapillary capillary layer, while 40.3% of the eyes with ODE had nonspecific focal vessel density decrease around the optic nerve head. Larger ODD were significantly associated with a vessel density decrease on OCTA (P = .009). The disc diameter positively correlated with the ODD area (r = 0.245; P = .018) and negatively correlated with the ODD height (r = -0.237; P = .023).

CONCLUSIONS

En face OCT showed the characteristic features of buried ODD compared to those of ODE or normal optic discs. The demarcation of buried ODD from the optic nerve axons on en face OCT and the poor vascular perfusion of buried ODD on OCTA suggest that buried ODD are materials deposited around the optic disc rather than the herniated optic nerve axon fibers.

Clinical Features of Ocular Motility in Idiopathic Orbital Myositis

: Objective: To elucidate the clinical features of ocular motility and the risk factors for recurrence in idiopathic orbital myositis.

METHODS

The medical records of 31 patients diagnosed with idiopathic orbital inflammation between 2003 and 2019 were retrospectively reviewed. All patients were initially treated with corticosteroids. Treatment outcome and ocular motility were noted.

RESULTS

Twenty-six patients (84%) had unilateral involvement and five patients (16%) were bilateral. Of the 31 patients, 22 patients (71%) showed ocular motility limitation. The mean grading scale of extraocular muscle (EOM) limitation was -1.65 ± 1.80. EOM limitation was found in the same direction of the most affected muscle in 14 patients (64%), while 8 patients (36%) showed duction limitation in the opposite direction. Nine patients (35%) suffered from recurrence. Recurrence was more likely to occur in patients with multiple muscle involvement (p < 0.001). The interval to relapse of symptoms after discontinuation of steroids was significantly shorter in patients with multiple recurrences compared to those with a single recurrence (1.8 ± 0.8 weeks versus 6.0 ± 1.4 weeks, p = 0.020).

CONCLUSIONS

Idiopathic orbital myositis showed variable degrees of ocular motility limitation, and limitation in the same direction of the action of the affected muscle was more frequent. Recurrent myositis was more likely to have multiple muscle involvement. Rapid relapse of symptoms after discontinuation of steroids was a significant indicator of multiple recurrences.

Surgical outcomes of strabismus after iatrogenic ophthalmic artery occlusion caused by cosmetic filler injections

BACKGROUND

To investigate the surgical outcomes of strabismus related to iatrogenic occlusion of the ophthalmic artery and its branches from cosmetic facial filler injection.

METHODS

A retrospective study was performed on 6 patients who underwent strabismus surgery among 23 patients who had suffered occlusion of the ophthalmic artery and its branches after cosmetic facial filler injection. Initial, preoperative and final ocular motility examinations, the type of surgery and surgical outcomes were evaluated.

RESULTS

At initial presentation, visual acuity was no light perception in 5 patients and hand motion in one patient. Five out of 6 patients showed initial ophthalmoplegia. Among these 5 patients, eye motility fully recovered in 3 patients although sensory strabismus developed during follow-up, while the remaining 2 patients had persistent ocular motility limitations. Strabismus surgery was performed at 2.2 ± 1.5 years after iatrogenic ophthalmic artery occlusion. Preoperatively, 5 of the 6 patients showed exotropia, and one patient had esotropia. Vertical deviation was found in 3 out of 6 patients in addition to the horizontal deviation. Successful outcome was achieved only in the 4 patients without persistent ophthalmoplegia after 1.4 ± 1.0 years from surgery. The other two patients with persistent ocular motility limitations failed to achieve successful alignment after surgery, and one patient eventually underwent evisceration due to phthisis bulbi.

CONCLUSIONS

In our study, surgical outcomes of strabismus caused by cosmetic facial filler injection were successful only in patients without persistent ophthalmoplegia at the time of surgery.

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.

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.

Serological evidence of bluetongue virus infection and serotype distribution in dairy cattle in South Korea

Background

Bluetongue is a vector-borne viral disease, and bluetongue virus (BTV) outbreaks can cause substantial economic losses. Even subclinical infection may carry significant associated costs, including a loss of condition, reduced milk yield, and infertility and abortion, and indirect costs, largely due to the export restrictions and surveillance requirements imposed to limit the spread of the virus. However, the BTV epidemiology in the Far East remains incompletely understood, especially in the cattle population in South Korea. In this study, the seroprevalence of BTV antibodies and distribution of BTV serotypes in dairy cattle in South Korea were evaluated to improve the understanding of the BTV epidemiological situation in the Asia-Pacific region.

Results

Between 2012 and 2013, a total of 37 out of 171 dairy cattle herds (21.6%) and 85 out of 466 dairy cattle heads (18.2%) showed antibodies against BTV. Neutralizing antibodies to BTV-1, − 2, − 3, − 4, − 7, − 15, and − 16 serotypes were identified, and the RNAs of the BTV-1, − 2, − 3, − 15, and − 16 serotypes were detected, indicating that BTV was circulating in the dairy cattle population in South Korea.

Conclusions

These findings indicate that BTV is widespread and has circulated in dairy cattle in South Korea. This is the first report presenting evidence of circulating antibodies against BTV and the serotype distribution in bovine populations in South Korea.