Optic nerve disease is an important cause of vision loss. When a reddish and swollen disc is observed, optic nerve disease may be suspected; however, this does not necessarily mean that the optic nerve is the primary cause, as the changes may be secondary to other diseases. Furthermore, if there is no abnormality in the fundus, including the optic nerve, diseases of the retrobulbar optic nerve to the optical center should be considered. In this article, we first outline the procedure for diagnosing visual loss and introduce some congenital optic nerve abnormalities that must be differentiated from optic nerve diseases.

　When a patient with reduced vision presents at the hospital, a detailed history taking is conducted. If optic nerve disease is suspected, first of all, relative afferent pupillary defect (RAPD) is tested. If fundus examination reveals optic disc swelling, it is necessary to differentiate between the common condition of optic papillitis and ischemic optic neuropathy. In the case of optic papillitis, circumferential swelling of the optic disc occurs; and in the case of anterior ischemic optic neuropathy, partial swelling of the optic disc is observed. The key finding to differentiate from optic disc swelling due to uveitis is the presence of retinal vasculitis around the optic nerve. OCT and OCT angiography can be useful tools for the differential diagnosis of optic disc swelling.

　Optic disc swelling occurs due to axoplasmic flow stasis. It is observed in various optic nerve diseases, including ischemic, inflammatory, and toxic optic neuropathies and papilledema caused by increased intracranial pressure. Pseudopapilledema caused by congenital anomalies, such as a small optic disc (small cupless disc) and optic disc drusen, also lead to optic disc swelling. Therefore, differentiation of true papilledema and pseudopapilledema is crucial as both can present optic disc swelling upon ophthalmoscopic examination. Moreover, distinction between unilateral and bilateral conditions is necessary to diagnose optic disc swelling as the epidemiologies of both conditions are significantly different. Examination of both eyes is essential for cases with optic disc swelling. This section outlines the clinical approaches for conditions associated with optic disc swelling, including papilledema, uveitis, hypertensive optic neuropathy, diabetic optic neuropathy, hypertrophic meningitis, and carotid–cavernous sinus fistula.

　Optic nerve atrophy is characterized by irreversible degeneration of the optic nerve and retinal ganglion cells because of various etiologies. Major causes include ischemic optic neuropathy, hereditary optic neuropathies (such as Leber’s hereditary optic neuropathy and dominant optic atrophy), nutritional optic neuropathy, and toxic optic neuropathy. When optic nerve atrophy is encountered, a detailed patient history and various examinations are necessary for differential diagnosis. Although many conditions that cause optic nerve atrophy are challenging to treat, some are reversible or their progression can be prevented with early intervention, highlighting the importance of precise diagnosis.

　The optic disc is a critical structure that aggregates the axons of ganglion cells in the retina and transmits visual information to the brain. Damage to this region significantly affects visual acuity and fields, ultimately impeding the “Vision of Life.” It is well-established that various diseases can cause changes in the optic disc. For instance, in glaucoma, characteristic changes such as optic disc cupping enlargement, notching, and bayoneting are essential for diagnosis. Diverse morphological changes in the optic disc have been observed in myopic eyes, including localized defects of the lamina cribrosa, peripapillary chorioretinal atrophy, and acquired pits. These changes were pronounced in highly myopic eyes. Other conditions, such as post-fundus hemorrhage, retinitis pigmentosa, and superior segmental optic disc hypoplasia, can also affect the optic disc. Differentiating these conditions from glaucoma is crucial to ensure appropriate management. Because structural changes in the optic disc often precede visual function impairment, it is important to understand the alterations in optic disc appearance that are associated with various ocular diseases.

Purpose: Since 2015, Spot Vision Screeners (SVS) have been used during infant health checkups, showing potential for early detection of ophthalmic abnormalities. This study aimed to investigate the follow-up care for infants with asymptomatic anisocoria detected using SVS and to clarify the current practices.

Methods: We retrospectively examined six infants (four boys, two girls) who were diagnosed with asymptomatic anisocoria at the National Center for Child Health and Development between September 2017 and September 2023. The study examined factors such as age, examination outcomes, and whether detailed follow-up examinations were conducted.

Results: Of the six infants, three underwent detailed examinations, whereas three did not. For infants who were examined, all imaging and blood test results were normal. Two cases were diagnosed with congenital Horner’s syndrome, and one with refractive amblyopia. No neuroblastomas were identified.

Conclusion: No clear guidelines have yet been established regarding the need for detailed follow-up examinations for infants with asymptomatic anisocoria detected using SVS. Given the considerable burden of additional testing and the frequent refusal by guardians, further academic consensus is needed. More discussion is required to determine the necessity of in-depth examinations for asymptomatic anisocoria.

　A 52-year-old woman received total parenteral nutrition for 28 years following small bowel resection for chronic nonspecific multiple ulcers of the small intestine. She presented with a 3-month history of decreased visual acuity in her right eye. Her corrected visual acuity was 0.5 and 1.2, and the critical flicker fusion frequencies were 17-23 Hz and 36-41 Hz in the right and left eyes, respectively. The right eye tested positive for afferent pupillary defects. The symptoms progressed, and 2 weeks later, visual field testing revealed central scotomas in both eyes. Blood tests revealed macrocytic anemia and low selenium levels, which led to the suspicion of selenium deficiency. Intravenous selenium was administered, and as the selenium concentration recovered, visual function gradually improved. Eight months after selenium supplementation, her corrected visual acuity improved to 1.0 and 1.2, with critical flicker fusion frequencies of 32-35 Hz and 32-37 Hz in the right and left eyes, respectively. The central scotomas had disappeared. This is the first report of visual recovery following selenium supplementation in a patient with selenium-deficiency-induced optic neuropathy. When visual impairment is observed in patients receiving total parenteral nutrition, it is essential to consider selenium-deficiency-induced optic neuropathy in the differential diagnosis.

　We present a case of pediatric pituitary apoplexy in a 13-year-old girl who experienced headache for six months, which worsened severely one month prior to presentation. She visited a local ophthalmologist due to vision loss in the left eye and was referred to our hospital with suspected optic neuritis. At the initial visit, her corrected visual acuity was 1.5 in the right eye and 0.7 in the left eye, with intraocular pressures of 16 mmHg in both eyes. Critical flicker fusion frequency (CFF) was 41 Hz in the right eye and 34 Hz in the left eye, and no relative afferent pupillary defect (RAPD) was noted. Examination of the anterior segment and optic media revealed no abnormalities. Fundus examination showed a normal right eye and temporal pallor of the optic disc in the left eye. Optical coherence tomography revealed thinning of the circumpapillary retinal nerve fiber layer in the temporal sectors of both eyes. Goldmann perimetry detected a temporal vertical step in the right eye and a central scotoma in the left eye, consistent with a junction scotoma pattern. Magnetic resonance imaging identified a cystic lesion with a hematoma in the pituitary region, leading to a diagnosis of pituitary apoplexy due to pituitary adenoma. The patient was referred to neurosurgery, and pituitary tumor resection was performed 1.5 years later. Postoperatively, her visual acuity improved to 1.5 in both eyes, CFF increased to 45 Hz in the right eye and 44 Hz in the left eye, and the central scotoma in the left eye resolved. Pediatric pituitary apoplexy should be considered in patients presenting with severe headache and visual dysfunction.

Background: Miller–Fisher syndrome (MFS) is a benign variant of Guillain–Barré syndrome characterized by ataxia, areflexia, and ophthalmoplegia. Most diseases, including optic neuropathy, affect the peripheral nervous system and are often unaffected by the central nervous system. In patients with alcoholism, differentiating them from Wernicke’s encephalopathy is necessary.

Purpose: To report a rare case of MFS with optic neuritis, indicating the central nervous system’s involvement.

Case report: A 37-year-old man with a history of heavy alcohol consumption presented with diplopia and blurred vision. The patient had good consciousness but fatigue, imbalance, and a tendency to drop objects while lifting was observed. Examination revealed bilateral ptosis, total ophthalmoplegia, and retrobulbar optic neuropathy, and neurological examination revealed a positive tandem gait test and normal deep tendon reflexes without motor or sensory deficits. Magnetic resonance imaging of brain and orbit demonstrated multiple cranial nerve enhancements, lumbar puncture revealed albuminocytological dissociation, and visual evoked potentials revealed delayed P100 latency, which was suspected to be bilateral optic neuritis-induced. Finally, a nerve conduction test revealed slow motor conduction velocity. The patient was diagnosed as having MFS and optic neuritis, and a serum test showing anti-GQ1b antibody seropositivity was used to confirm this diagnosis. The patient was administered intravenous immunoglobulin at 2 g/kg/course for 5 d. At 5 weeks of follow-up, the patient’s symptoms and signs gradually improved.

Conclusions: MFS usually presents with peripheral neuritis; however, central nervous system involvement was determined. Thus, cerebrospinal fluid, neuroimaging, and serological analyses support clinical diagnosis using anti-GQ1B antibodies testing.

Objective: Anterior communicating artery (ACoA) aneurysms may be associated with ocular manifestations, which can arise from either the rupture of the aneurysm or compression of the optic nerve and optic chiasm. In this study, we assessed the ocular manifestations associated with ruptured ACoA aneurysms.

Methods: A detailed search of databases such as PubMed Medline, SCOPUS, Web of Science, and Google Scholar was conducted to obtain data from relevant case reports published on ophthalmic manifestations of ruptured ACoA aneurysms from 1966 to the present.

Results: In total, 38 cases were identified and assessed from 23 research papers. The third (oculomotor) and sixth (abducens) were the most common ocular manifestations, affecting about 50% of the cases. Visual field defects were present in 36.8% of cases, with monocular visual loss being the most prevalent, representing 42.9% of the visual field defects.

Conclusions: Third and sixth cranial nerve palsies are the most common ophthalmic manifestation of ruptured ACoA aneurysms and generally have a more favorable prognosis than visual field defects, which are often permanent. In this study, we highlighted the significance of prompt evaluation of unexplained visual symptoms and recommended using standardized tools to evaluate recovery outcomes.

　Acquired ocular movement disorder causes diplopia and paralytic strabismus, significantly impacting the daily life of patients. Orthoptic training focuses on restoring the paralyzed muscle function and relieving antagonist muscle spasticity. It is primarily used to treat paralytic strabismus and blowout fractures caused by infranuclear disorders. Detailed pathological analyses and visual function evaluations are essential to determine the training eligibility of patients, with early training being crucial for improvement.

　Orthoptic training is used to improve the binocular visual function by expanding the fusional area, thereby reducing the daily life difficulties. It commonly involves saccadic eye movement and fusion lock training. Early vision training in eligible cases significantly improves the therapeutic outcomes, facilitating social reintegration and enhancing the patient quality of life.