Cause of acquired onset of diplopia due to isolated third, fourth, and sixth cranial nerve palsies in patients aged 20 to 50 years in Korea: A high resolution magnetic resonance imaging study

Imaging the brain: diagnosis aided by structural features on neuroimaging studies

The use of neuroimaging allows the ophthalmologist to identify structural lesions in the orbit or along the neuroaxis that allow for more accurate diagnosis and treatment of patients with neuro-ophthalmic diseases. The primary imaging tools include computed tomography (CT) and magnetic resonance imaging (MRI), both of which can be used to evaluate the brain, spinal cord and canal, and orbits. Neurovascular structures, both arterial and venous, also can be imaged in high resolution with modern CT and MR angiography and CT and MR venography. In many cases, invasive procedures such as catheter angiography can be avoided with these studies, and angiography is often reserved for confirmation of vascular lesions combined with endovascular treatment. In this article, we illustrate how the evaluation of patients presenting with neuro-ophthalmic diseases involving the afferent and efferent visual pathways can be optimized with the use of appropriate diagnostic imaging studies. The complementary value of ophthalmic imaging is also demonstrated, and the advantages and disadvantages of both CT and MRI as well as their use in longitudinal patient follow up is demonstrated.

Are isolated ocular motor nerve palsies in the elderly truly 'low risk' for abnormal neuro-imaging outcomes?

BACKGROUND

Neurologically isolated ocular motor nerve palsies often present a management dilemma. Neuroimaging is more likely to be offered to patients <50 years without coexisting ischaemic risk factors as their risk of sinister underlying causes is thought to be higher. However, populations are rapidly ageing and advanced neuroimaging is now more widely available. We thus investigated the incidence of abnormal neuroimaging outcomes in the traditionally low-risk older patient group.

METHODS

This is a retrospective cohort study of 353 patients presenting with isolated ocular motor nerve palsies to a tertiary neuro-ophthalmology service in Singapore over a four-year (2015 to 2019) period. Clinical data was obtained through manual review of case records. Common aetiologies, age-based differences in prevalence of causes and abnormal neuroimaging outcomes were statistically analysed.

RESULTS

Abnormal neuroimaging outcomes were significantly greater in the younger cohort only when age segregation was performed at 60 years of age. In a multivariate analysis, acute onset rather than ischaemic risk factors were independently predictive of normal neuroimaging outcomes. After adjusting for prior cancer risk and clinical bias from presumed ischaemic palsies, abnormal neuroimaging outcomes were seen in 14.1% ≥ 50 yrs, 10.9% ≥ 60 yrs and 15.1% ≥ 70 yrs.

CONCLUSIONS

In patients presenting with isolated ocular motor nerve palsies, acute onset may be a more reliable indicator of an ischaemic palsy rather than advanced age or presence of ischaemic risk factors. If onset is not acute, neuroimaging should be considered irrespective of age and coexisting ischaemic risk factors.

Ocular Motor Cranial Nerve Palsies and Increased Risk of Primary Malignant Brain Tumors: South Korean National Health Insurance Data

The aim of this study was to investigate the association between ocular motor cranial nerve palsies (OMCNP) and the occurrence of primary malignant brain tumors in a Korean population, using the national sample cohort database from Korea National Health Insurance Service (KNHIS). KNHIS data between 2010 and 2017 were analyzed. Our sample encompassed 118,686 participants, including 19,781 from a recently diagnosed OMCNP cohort and 98,905 from a matched control cohort through a 1:5 propensity score matching based on age and gender. To counteract the issue of reverse causation, we integrated a one-year time lag in our sensitivity analysis. Study participants were followed up until 31 December 2019. Cox proportional hazard regression analysis was used to compute the adjusted hazard ratio (HR) for primary malignant brain tumors according to the OMCNP diagnosis. Additionally, we performed a subgroup analysis to discern effects of various factors on the association between OMCNP and primary malignant brain tumors. HR for primary malignant brain tumors was 3.272 (95% confidence interval [CI]: 2.294 to 4.665) in the OMCNP cohort compared to the control cohort in a fully adjusted model for age, sex, socio-economic status, smoking, drinking, regular physical exercise, hypertension, diabetes, dyslipidemia, obesity, chronic kidney disease, and human immunodeficiency virus infection. Further subgroup analysis revealed that the risk of primary malignant brain tumors was significantly increased in women with OMCNP compared to men with OMCNP (HR: 5.118 in women vs. 2.441 in men, p = 0.0440), and in those aged <65 years than in those aged ≥65 years (HR: 6.951 in age < 65 years vs. 1.899 in age ≥ 65 years, p = 0.0006). Our population-based cohort study demonstrated a significantly increased risk of subsequent primary malignant brain tumors in patients with OMCNP. Particularly, OMCNP-afflicted women aged below 65 manifested a heightened probability of developing primary malignant brain tumors compared to those devoid of OMCNP.

Retrospective Analysis of Factors Related to the Long-Term Recovery of Third, Fourth, and Sixth Cranial Nerve Palsy with Etiologies and Clinical Course in a Tertiary Hospital

Purpose

Although various studies have explored the causes and clinical aspects of cranial nerve palsies, there remains a significant gap in understanding the prognostic factors that influence outcomes. In this study, we sought to address this gap by investigating the incidence, etiologies, clinical courses, and factors associated with long-term recovery, with the aim of enhancing the knowledge base in this field and providing valuable insights for improved patient care.

Patients and Methods

This retrospective study evaluated the data gathered from subjects who had third, fourth, and sixth cranial nerve palsy at the ophthalmology outpatient clinic of Phramongkutklao Hospital between April 1, 2012, and April 30, 2022.

Results

Among the three nerves, abducens nerve palsy was the most prevalent finding by most commonly involved. Our study revealed that ischemic and compressive lesions were the most common etiology of oculomotor nerve palsy, comprising 24.6% each. In addition, the most common etiology of trochlear and abducens nerve palsy was trauma, at 31.6% and 27.1%, respectively. Compared with the other nerves, oculomotor nerve palsy was associated with a shorter duration onset of symptoms and recovery period. The best recovery outcomes among the various etiologies were inflammation, ischemic events, and trauma in oculomotor, trochlear, and abducens nerve palsy, respectively. Logistic regression revealed that an onset of <7 days and isolated nerve involvement were significantly associated with good long-term outcomes, with an adjusted odds ratio of 1.73 (95% confidence interval, 1.03-2.89) and 2.56 (95% confidence interval, 1.21-5.39) adjusted for the type of cranial nerve palsy, aged at 50 years, sex, diabetes mellitus, hypertension, dyslipidemia, onset at 7 days, and number of cranial nerves involved, respectively.

Conclusion

The onset of symptoms in less than 1 week and isolated nerve involvement were associated with better prognosis in subjects with third, fourth, and sixth cranial nerve palsy.

Dynamic Changes in Metabolic Status Are Associated With Risk of Ocular Motor Cranial Nerve Palsies

BACKGROUND

To investigate whether recovery from or development of metabolic syndrome (MetS) in a population is associated with an altered risk for ocular motor cranial nerve palsy (CNP).

METHODS

This cohort study included 4,233,273 adults without a history of ocular motor cranial nerve palsy (ocular motor CNP) who underwent 2 consecutive biennial health screenings provided by the Korean National Health Insurance System between 2009 and 2011. They were followed up until December 31, 2018. Participants were categorized into a MetS-free, MetS-developed, MetS-recovered, or MetS-chronic group. A multivariable Cox proportional hazard regression model was used. Model 3 was adjusted for age, sex, smoking status, alcohol consumption, and physical activity.

RESULTS

Compared with the MetS-free group, the MetS-chronic group had the highest risk of ocular motor CNP (hazard ratio [HR]: 1.424; 95% confidential interval [CI]: 1.294-1.567, Model 3), followed by the MetS-developed group (HR: 1.198, 95% CI: 1.069-1.343), and the MetS-recovered group (HR: 1.168, 95% CI: 1.026-1.311) after adjusting for potential confounders. The hazard ratio of ocular motor CNP in men with chronic MetS was 1.566 (95% CI, 1.394-1.761) while that of women with chronic MetS was 1.191 (95% CI, 1.005-1.411). Among age groups, those in their 30s and 40s showed the highest association between dynamic MetS status and ocular motor CNP.

CONCLUSIONS

In our study, recovering from MetS was associated with a reduced risk of ocular motor CNP compared with chronic MetS, suggesting that ocular motor CNP risk could be managed by changing MetS status.

Trends in Etiologies, Demographics, and Neuroimaging in New-Onset Adult Strabismus at an Ophthalmic Emergency Department

PURPOSE

To evaluate new-onset strabismus in adults presenting to an ophthalmic emergency department, and to identify which patients require neuroimaging.

METHODS

This was a retrospective review of electronic medical records of patients 18 years and older who presented to an ophthalmic emergency department between January 1, 2019 and December 31, 2020 with new-onset strabismus. Data regarding demographics, causes, neuroimaging, and resolution were recorded and analyzed.

RESULTS

Of the 557 patients in the current study, 54.8% were men and the mean age was 57.3 ± 16.7 years (range: 18 to 92 years). Most patients (72.4%) presented with diplopia. Esotropia was the most common ocular misalignment (43.6%) and was more common in women than men (51.6% vs 37.0%, respectively) (P = .001). The most common diagnoses were cranial nerve palsies (66.8%) for both sexes and all age groups, with the most common etiology being microvascular (48.1%) for patients 50 years and older and idiopathic (20.1%) for patients between 18 and 49 years old. The incidence of cranial nerve palsies was significantly higher in older patients (P < .001). Neuroimaging was performed in 58% of patients (n = 323), of whom 37.2% (n = 120) had abnormal findings. The most common abnormal neuroimaging finding was mass for all age groups and sexes (19.2%). Patients with cranial nerve palsy and microvascular etiology had a significantly lower proportion of abnormal neuroimaging findings (P < .001).

CONCLUSIONS

Most cases of new-onset strabismus in adults presenting to the emergency department were due to cranial nerve palsy, particularly in older patients. Despite high rates of neuroimaging, patients with cranial nerve palsy had mostly normal findings. The current study supports the belief that neuroimaging may be deferred in patients older than 50 years with micro-vascular risk factors. [J Pediatr Ophthalmol Strabismus. 2022;59(4):269-273.].

Clinical outcomes and etiology of acquired sixth cranial nerve palsy

ABSTRACT

The objective of this study was to investigate the difference in clinical features according to age and factors affecting recovery of acquired sixth cranial nerve (CN6) palsy.A total of 156 patients with acute CN6 palsy between March 2016 and August 2021 who were followed up for at least 3 months were included in this study. Etiology, rate of recovery, and factors associated with recovery were retrospectively investigated.The average age of patients with CN6 palsy was about 60years and the mean duration of recovery was about 2.5 months. Of 156 patients, 72 (46.15%) had a microvascular etiology and 25 (16.03%) patients had a brain vascular lesions. Brain neoplasm, trauma, and "others" were found in 10 (6.41%), 11 (7.05%), and 15 (9.62%) patients, respectively. Among the total of 156 patients, 28 (17.95%) failed to completely recover. Non-isolated CN6 palsy with other cranial nerve palsies were recorded in 29 (18.59%) cases. Comparison of age (<50years vs ≥50years), between recovery and non-recovery groups showed that etiology was significantly different.The recovery rate of acquired CN6 palsy was about 82% and about 27% of patients had brain lesions. Also, varying rates and duration of recovery were found according to etiology, so we should be pay attention to diagnosis of causative disease in CN6 palsy patients.

Association of Obesity and Incidence of Third, Fourth, and Sixth Cranial Nerve Palsies

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

To assess the association between obesity and the development of third, fourth, and sixth cranial nerve palsy (CNP).

METHODS

We analyzed a cohort of 4,067,842 adults aged between 20 and 90 years who underwent health checkups within the National Health Insurance Service between January 1 and December 31, 2009. The participants were followed until December 31, 2017. Cox proportional hazards regression analysis was used to determine the adjusted hazard ratios (HRs) for CNP. Model 3 (the main analysis model) was adjusted for age, sex, smoking status, alcohol consumption, and physical activity. Model 4 was additionally adjusted for hypertension, dyslipidemia, and diabetes mellitus in the setting of model 3.

RESULTS

A total of 5,835 individuals were diagnosed with CNP during the follow-up period (7.3 years). General obesity (body mass index [BMI] ≥25 kg/m²) was associated with an increased risk of CNP compared to individuals without general obesity (model 3, HR 1.248, 95% CI 1.184-1.315; model 4, HR 1.162, 95% CI 1.102-1.227). Abdominal obesity (waist circumference [WC] ≥90 cm in men and ≥85 cm in women) also showed an increased HR compared to individuals without abdominal obesity (model 3, 1.239, 95% CI 1.170-1.313; model 4, HR 1.127, 95% CI 1.062-1.196). Compared to the group without either type of obesity, the group with only abdominal obesity (model 3, HR 1.167, 95% CI 1.035-1.317), the group with only general obesity (HR 1.19, 95% CI 1.14-1.24), and the group with both obesity types (HR 1.317, 95% CI 1.236-1.404) showed increased HRs for CNP.

CONCLUSION

Based on our population-based cohort study, both general and abdominal obesity increased the risk of CNP. Also, the combination of general and abdominal obesity may further increase the risk of CNP.

Ocular manifestations of multiple sclerosis in patients from three countries: A Web-based survey

OBJECTIVE

This study evaluates the epidemiological characteristics, ophthalmological manifestations, and different therapeutic options available for patients with multiple sclerosis (MS) in China, Spain, and Cuba.

METHODS

A self-designed questionnaire was used to conduct a comparable descriptive cross-sectional study on patients with MS. The survey included patients' demographic data, ocular manifestations related to MS, and treatment methodology followed in the three countries. The online survey was designed using the Wenjuanxing survey platform, and a survey link was circulated through WhatsApp, WeChat, and emails. Quantitative data were expressed as mean and standard deviation, the Kruskal-Wallis test was used for non-parametric variables. Qualitative data were expressed as numerical and percentage. The chi-square test (χ²) was used to compare the group's response categories. The statistical difference was considered significant when p < 0.05.

RESULTS

The female-to-male ratio in all the three countries was 2-3:1, and relapsing-remitting MS (RRMS) was the most frequent in all three countries. Vision loss was slow and progressive in half of the patients from the three countries, with no significant differences (p = 0.524). A higher percentage of steroid treatment was observed in Chinese patients in comparison with the patients from other two countries (p < 0.001), and a similar trend was seen in the use of traditional medicines. Almost one-third of patients who did not receive any treatment recovered spontaneously in all the three countries (p = 0.097).

CONCLUSIONS

MS occurs more frequently in the relapsing-remitting clinical form and there is a clear female predominance. The first ocular crisis or clinical debut of MS is characterized by slow and progressive visual impairment, increasing and adding to other ocular manifestations during its evolutionary course. Spontaneous recovery of vision after an attack of optic neuritis in the course of MS is possible.

Oculomotor nerve palsy in an asymptomatic child with COVID-19

We report the case of a 2-year-old girl with acute-onset divergent strabismus and ptosis in the right eye. She had an exotropia of 45^Δ for near, eyelid ptosis affecting the visual axis, adduction, limitations of up- and downgaze, and a discrete mydriasis in the right eye. Neurological conditions were ruled out. Serology was positive for SARS-CoV-2 antibodies. The patient was managed conservatively with ocular physiotherapy and close visual acuity monitoring. On follow-up examination at 1 month, there was marked improvement of the exotropia (25^Δ for near), adduction, ptosis, and mydriasis.

Acute abducens nerve palsy in a patient with the novel coronavirus disease (COVID-19)

We present a case of an abducens nerve palsy in a previously healthy young man in the setting of SARS-CoV-2 infection. Magnetic resonance imaging obtained 5 weeks after the onset of diplopia demonstrated an atrophic left lateral rectus muscle, which was hyperintense on T2 weighting, consistent with denervation. Although the mechanism of the nerve palsy remains unclear, it is suspected to be related to his viral illness, because the patient had no preexisting vascular risk factors or evidence of other neurologic disease on neuroimaging. Cranial nerve palsies may represent part of the neurologic spectrum of COVID-19.