Cranial Nerve Palsies in the Setting of Arachnoid Cysts: A Case Series and Literature Review.

BACKGROUND: Arachnoid cysts (ACs) are benign lesions typically believed to not cause neurologic defects in the adult population and are most often found incidentally on imaging. We describe 2 patients with ACs potentially leading to isolated cranial nerve (CN) dysfunction. METHODS: We describe 2 patients, 1 with a fourth nerve palsy and the other with a sixth nerve palsy found to have ACs on MRI brain imaging in locations that potentially caused a compressive CN palsy. We review previous literature of ACs presenting with CN III, IV, or VI palsy. RESULTS: Patient 1 was a 62-year-old man who presented with a 22-year history of diplopia with strabismus examination consistent with a congenital CN IV palsy. Despite multiple surgeries, his CN IV palsy insidiously worsened. An AC in the posterior fossa with mass effect on the quadrigeminal plate and asymmetric atrophy of the right superior oblique was identified on imaging. Patient 2 was an 80-year-old man who presented with an 18-year history of diplopia and was found to have a left esotropia and abduction deficit consistent with complete CN VI palsy. An AC in the left cavernous sinus was identified on imaging. He underwent strabismus surgery with satisfactory resolution of diplopia. We identified a total of 18 previously published cases: 8 reports of CN III palsy, 4 reports of CN IV palsy, and 6 reports of CN VI palsy. Patient ages ranged from 1 to 67 with a median of 34.5. In 16/18 (89%) cases, the diagnosis of ACs was made within 1 year of symptom onset. Surgical removal of the AC was successful in resolving diplopia in 7/12 (58%) cases. In no case was strabismus surgery performed as primary treatment. CONCLUSIONS: Although ACs are typically congenital asymptomatic lesions, we present a case series of 2 patients with ACs in anatomic locations that potentially caused chronic, progressive, isolated CN palsies leading to strabismus. Our literature review revealed that most published cases detailing this clinical scenario resulted in neurosurgical fenestration of ACs with mixed results. Our cases represent 2 patients with AC-associated CN palsy treated with strabismus surgery.

A Tale of Progressive Painless Vision Loss in a 64-Year-Old Man Due to Leber Hereditary Optic Neuropathy.

ABSTRACT: A 64-year-old man presented with painless sequential bilateral vision loss, consistent with optic neuropathy, over the span of months. The significant decline in his visual function was out of proportion to the appearance of the optic nerves (which were not pale) or changes in his retinal nerve fiber layer thickness on optical coherence tomography. Neuroimaging revealed only mild T2 signal abnormality and faint enhancement in the left optic nerve. Extensive workup for potential infectious, metabolic, inflammatory, and ischemic etiologies was unremarkable. Empiric treatment with intravenous steroids did not slow or ameliorate the vision loss. Ultimately, genetic analysis revealed a missense m.11778G>A mutation in mitochondrial MT-ND4 gene, consistent with Leber hereditary optic neuropathy. Initiation of multivitamin supplements and idebenone unfortunately did not result in recovery of vision.

Neuro-ophthalmic manifestations of cancer: a narrative review.

BACKGROUND AND OBJECTIVE: Neuro-ophthalmic manifestations of cancer are vast and early recognition of a serious ocular condition due to either cancer or its therapy is important for both vision preservation as well as providing valuable treatment and prognostic information regarding the underlying malignancy. This review focuses on direct and indirect effects of cancer on the eye and its adnexa, hematologic malignancy, complications of traditional and novel oncologic therapies, and paraneoplastic syndromes as they relate to the eye as these disorders can lead to potentially devastating or irreversible vision loss. METHODS: PubMed was searched primarily for the following topics: optic nerve infiltration, primary vitreoretinal lymphoma (PVRL), ocular paraneoplastic disorders, and ophthalmic complications of cancer therapeutics. Literature was selected based on historical significance and landmark studies (e.g., Cross et al. series of paraneoplastic optic neuritis patients; Chan's textbook on primary intraocular lymphoma) as well as publications published after 2000. References from select studies were additionally included. Given the sparsity of literature on many subjects, most publications were included during this time frame in our review. KEY CONTENT AND FINDINGS: There are several ophthalmic entities that the oncologist should be aware of including leukemic optic nerve infiltration, PVRL, paraneoplastic syndromes as they related to the eye, and adverse effects of therapeutics. Unfortunately, given the rarity of some of these entities [e.g., paraneoplastic optic neuropathy (PON), cancer-associated retinopathy (CAR)], diagnosis can be difficult and treatment options are often limited. CONCLUSIONS: Oncologists can develop a set of basic ophthalmology examination skills that will help to triage and manage patient eye complaints. In certain instances, oncologists have the potential to avert devastating vision loss with early recognition of neuro-ophthalmic complications.

High-Speed Balanced-Detection Visible-Light Optical Coherence Tomography in the Human Retina Using Subpixel Spectrometer Calibration.

Increases in speed and sensitivity enabled rapid clinical adoption of optical coherence tomography (OCT) in ophthalmology. Recently, visible-light OCT (vis-OCT) achieved ultrahigh axial resolution, improved tissue contrast, and provided new functional imaging capabilities, demonstrating the potential to improve clinical care further. However, limited speed and sensitivity caused by the high relative intensity noise (RIN) in supercontinuum lasers impeded the clinical adoption of vis-OCT. To overcome these limitations, we developed balanced-detection vis-OCT (BD-vis-OCT), which uses two calibrated spectrometers to cancel RIN and other noises. We analyzed the RIN to achieve robust subpixel calibration between the two spectrometers and showed that BD-vis-OCT reduced the A-line noise floor by up to 20.5 dB. Metrics comparing signal-to-noise-ratios showed similar image qualities across multiple reference arm powers, a hallmark of operation near the shot-noise limit. We imaged healthy human retinas at an A-line rate of 125 kHz and a field-of-view up to 10 mm ×4 mm. We found that BD-vis-OCT revealed retinal anatomical features previously obscured by the noise floor.

A unique case of benign intermittent upbeat nystagmus triggered by light stimulation.

A 3-month-old girl with no past medical history presented with new-onset intermittent upbeat nystagmus. Episodes were triggered by movement into the supine position as well as by bright light flashes. They lasted a few seconds and were not associated with any distress. Neurological examination and work-up, including magnetic resonance imaging of the brain and abdominal ultrasonography, were normal. The eye movements completely resolved after 3 months.

Eye Disease in Medical Practice: What You Should Know and Why You Should Know It.

Incidence of cataract, diabetic retinopathy, macular degeneration, and glaucoma will significantly increase by 2050. Visual impairment can increase morbidity and mortality in nonocular disease. There are different patterns of vision loss in cataract, diabetic retinopathy, age-related macular degeneration, and glaucoma. Internists and medical subspecialists play an important role in prevention, detection, and early treatment of eye disease. Awareness of screening guidelines for eye disease as well as a basic ocular history and simple penlight examination can decrease incidence of vision loss and its impact. Visual impairment places a significant financial burden on society.

Automated Pupillometry as an Adjunct to Clinical Examination in Patients With Acute Vision Loss.

BACKGROUND: Despite automated pupillometry's (AP) improved detection of relative afferent pupillary defects (RAPDs) compared with the Swinging Flashlight Test (SFT), AP remains uncommon in clinical practice. This study examined barriers to routine use of AP in evaluation of acute vision loss. METHODS: (1) Ophthalmologists and optometrists' perceptions of AP were captured via electronic survey. (2) Ophthalmologists were presented with clinical vignettes to assess their use of AP in clinical decision-making. (3) Patients presenting with decreased vision to an ophthalmology urgent care clinic underwent manual SFT and AP screening to evaluate ophthalmologists' perceptions of the device. RESULTS: Surveys indicated that clinicians were "neutral" to "somewhat likely" to use AP. In clinical vignettes, more physicians proceeded with workup for optic nerve pathology when presented with an RAPD by AP than SFT (77% vs 26%, P = 0.003). When SFT and AP results were discordant, more physicians proceeded with workup for optic nerve disease when AP was positive and SFT was negative than vice versa (61% vs 18%, P = 0.008). In the clinical study of 21 patients, 50% of RAPDs detected by AP were not detected by SFT, although ophthalmologists rated AP's usefulness as only "neutral" to "somewhat useful." CONCLUSION: Clinicians value pupillary examination and trust AP over SFT; however, widespread adoption and perceived value of AP may depend on its impact on clinical outcomes. Within a comprehensive diagnostic device, AP may be an important tool, but is not necessary to screen for optic nerve disease or evaluate acute vision loss.

Retinal disease in the neurology clinic.

PURPOSE OF REVIEW: Retinal disease can manifest with visual symptoms similar to those which result from central nervous system disorders. We provide a framework for considering retinal causes of common visual complaints presenting to a neurology clinic. RECENT FINDINGS: Technological advances have afforded quicker detection and a more thorough understanding of these retinal entities and are crucial to consider when evaluating visual complaints in the neurology clinic. SUMMARY: It is essential to maintain a working knowledge of common retinal conditions that symptomatically overlap with common neurologic conditions. Furthermore, the ophthalmoscopic exam and retinal imaging modalities can both aid in the diagnosis and workup of visual complaints and neurologic disease.

Nailfold Capillary Hemorrhages: Microvascular Risk Factors for Primary Open-Angle Glaucoma.

BACKGROUND: Primary open-angle glaucoma (POAG) is associated with systemic microvascular dysfunction including hemorrhages and other abnormalities of the nailfold capillary bed. This study aimed to verify the specificity of nailfold capillary hemorrhages and other abnormalities as risk factors for POAG. METHODS: Nailfold video capillaroscopy was performed using a JH-1004 capillaroscope on the fourth and fifth digits of the nondominant hand in control (n = 277), POAG (n = 206), OHT (n = 57), and SG (n = 29) subjects. The number of hemorrhages, dilated capillaries >50 µm, and avascular zones ≥200 µm were counted and adjusted to counts per 100 capillaries. Descriptive analyses as well as univariate- and multivariable-adjusted logistic regression were performed comparing all groups with controls and POAG with OHT and SG. Subanalyses were conducted in POAG patients examining the association between nailfold capillary outcomes and previous glaucoma surgery, successful IOP control, or disease severity. RESULTS: All nailfold capillary outcomes were significantly increased in POAG, no outcomes were increased in SG, and only hemorrhages were mildly increased in OHT. Hemorrhages were significantly more frequent in POAG compared with both OHT (P < 0.0001) and SG (P=0.001). There were significant trends between higher numbers of hemorrhages and POAG compared with controls, OHT, and SG, with odds ratios of 18.3 (8.5-39.4), 9.1 (1.9-13.4), and 11.8 (1.7-7.3), respectively, for the presence of two or more hemorrhages per 100 capillaries. Hemorrhages were not significantly associated with previous glaucoma surgery, successful postoperative IOP control, or disease severity in POAG. CONCLUSIONS: These findings suggest that systemic microvascular dysfunction is frequent in POAG and occurs early in the disease process. The high specificity of nailfold hemorrhages makes them viable clinical risk factors for POAG.

Pupillometry measures of autonomic nervous system regulation with advancing age in a healthy pediatric cohort.

PURPOSE: To determine if variables of the pupillary light response mature with age and sex in a healthy pediatric cohort and the utility of pupillometry in assessment among pediatric participants. METHODS: After 1 min in a dark room to establish baseline, pupillometry was performed on 323 healthy, pediatric participants (646 eyes; 2-21 years; 175 females). Variables included initial pupil diameter, pupil diameter after light stimulus, percent pupillary constriction, latency to onset of constriction, average constriction velocity, maximum constriction velocity, average dilation velocity, and time from light stimulus to 75% of the initial pupil diameter. Data analyses employed ANOVAs and non-linear regressions. RESULTS: Analyses of age group differences revealed that participants 12-21 years old had a larger initial pupil diameter and pupil diameter after light stimulus, with males aged 12-18 years demonstrating a larger pupil diameter than all younger participants (ps < 0.05). Participants 12-18 years old had a slower maximum constriction velocity than participants 6-11 years old, with no sex differences (ps < 0.05). Furthermore, males aged 12-18 years old had a smaller percent constriction than males 6-11 years old (ps < 0.05). Regressions revealed that percent constriction and dilation velocity seemed to mature linearly, initial pupil diameter and ending pupil diameter matured quadratically, and the constriction velocity terms matured cubically. CONCLUSIONS: Results revealed maturation of the pupillary light response by age and sex in healthy pediatric participants. Given the value of the pupillary light response as a biomarker, the results provide normative benchmarks for comparison in health and disease, including opiate-exposed and concussion patients.