Traditionally, noninvasive brain-function studies are based on responses evoked while performing certain tasks or exposure to certain stimuli. This approach can explore detailed local brain functions; meanwhile, it also has some limitations in resolving global functional integration of neural circuitry. Recently, a default-mode network was established as brain activation“at rest”; however, this network gets deactivated while performing certain goal-oriented tasks. Spontaneous brain activity is closely correlated with conventional task-based activity. To functionally integrate brain circuitry, a graph-based theoretical approach using data from MR signals that reflect spontaneous brain activity without goal-oriented tasks. Historical progress in brain function studies is explained here.

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Brightness, glare, or glossiness can be a trigger for photophobia. These factors are similar but not the same. However, the concept of a visual dynamic range is important with respect to the cross-interpretation of three factors-brightness, glare, and glossiness. From the point of view of brain damage in photophobia, patients with a migraine often experience photophobia; however, it is difficult to localize the lesion in the brain. Some case reports have shown that the lesion associated with photophobia is adjacent to the chiasma, pulvinar, or ventral occipital cortex. A brain-activation study in healthy subjects showed that the broad visual cortex was associated with photophobia. However, the ventral occipital area was associated with glossiness. Impairment of the visual dynamic range is of two types: one that reduces the width of the range, and the other that impairs the shift in the visual dynamic range itself. It is possible to trigger photophobia in each type of impairment. The mechanisms underlying photophobia in the retina or in the brain are still unknown.

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It is generally believed that patients with homonymous hemianopia caused by retrogeniculate lesions do not show any funduscopic abnormality, and that damage to retinal ganglion cells (RGCs) beyond the synapse at the lateral geniculate nucleus does not occur in such patients. We treated patients with homonymous hemianopia following unilateral posterior cerebral artery (PCA) infarction and evaluated their macular ganglion cell complex (GCC) thicknesses. Our findings suggest that the degeneration of the RGCs in the retina, which corresponds to the homonymous hemianopia, can occur within a few years after PCA infarction. It is also indicated that the evaluation of the macular GCC may be superior to the evaluation of the circumpapillary retinal nerve fiber layer for the detection of nerve fiber damage in homonymous hemianopia. The ganglion cell layer, inner plexiform layer, and GCC were significantly thinner on the hemianopic side of the patients with cerebral artery stroke than on the unaffected side and in normal subjects. An area analysis revealed striking thinning in the most central part of the macula, close to the fovea. A regression analysis revealed a negative linear relationship between the time after stroke and the inner retinal thicknesses on the hemianopic side. Moreover, the significance and deviation maps of the abnormal area, as well as the GCC thicknesses, on the hemianopic side significantly correlated with the visual field defects. Furthermore, during the long-term follow-up of the retinal thickness in patients with hemianopia and lesions limited to the posterior pole of the occipital lobe, although changes were not observed immediately after the onset of the brain lesion, hemianopic thinning became apparent a few years later. These findings can be explained by the presence of the trans-synaptic retrograde degeneration of RGCs and their fibers. However, PCA infarction may directly affect the axons of the RGCs in the anterior visual pathways.

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Three cases of relapsing orbital myositis that responded well to steroid therapy, but recurred during steroid tapering, were identified. The recurrence was associated with severe pain in different extraocular muscles and the contralateral eye.
Case 1 was 62-year-old male patient. He had 5 recurrent episodes of orbital myositis that had responded well to steroid therapy; however, immunosuppression, including methotrexate (MTX) and oral prednisolone (PSL), was required for reducing the recurrence rate. Case 2 was 29-year-old male patient. He received radiation therapy after the third recurrence. Subsequently, he visited another hospital and was treated with PSL and MTX, but relapsed. He had a total of 5 episodes of recurrence; local injection of triamcinolone acetonide (TA), in addition to PSL and MTX, effectively reduced the frequency of relapse for over 3 years after the last recurrence. Case 3 was 41-year-old female patient. Her first visit to our department was with her sixth recurrence of orbital myositis. She was started on steroid pulse therapy, but inflammation of her right orbit recurred during pulse therapy. Subsequently, MTX and PSL were prescribed. She experienced steroid glaucoma when the PSL dose was increased from 25 mg to 40 mg. Despite the use of glaucoma drops, she developed uncontrollably high intraocular pressure and a trabeculotomy was performed. Since her trabeculotomy, PSL and MTX have prevented disease recurrence.
The outcomes of these cases suggest that treatment of relapsing migratory orbital myositis requires immunosuppression, including local injection of TA and oral PSL, given at an earlier stage of the disease.

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Orbital inflammation associated with paraneoplastic syndromes is rarely studied. A 78-year-old man presented with bilateral visual disturbance, along with eyelid edema, conjunctival hyperemia, and proptosis. He was diagnosed with lung cancer eight months before, and had achieved complete remission by chemotherapy three months before. The orbital MRI findings revealed mild bilateral swelling of the extraocular muscles and orbital fat, and slight signs of left-sided optic nerve inflammation. The results of serological analysis indicated an elevated serum interleukin-6 (IL-6) level, reflected by the elevated level of C-reactive protein, anemia with rouleaux formation, and polyclonal hyperglobulinemia. Nuclear imaging findings revealed solitary accumulations of the radiotracer in the mediastinal lymph nodes and histological analysis of these biopsied lymph nodes specimen indicated metastasis of lung adenocarcinoma. Treatment of the coexisting neoplastic fever with 20 mg of oral prednisolone led to an immediate improvement in both orbital inflammation and visual acuity. Orbital inflammation had not recurred despite the partial effectiveness of the subsequent chemotherapy.
In this case, the orbital inflammation may have resulted from auto-inflammation due to the presence of various inflammatory cytokines, which were abnormally activated as a non-specific immune response against the tumor cells. Paraneoplastic syndrome may be associated with orbital inflammation. Specific serological findings induced by an elevated serum IL-6 level can have diagnostic value.

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We report a rare case of macular hypoplasia with retinal folds in a patient with septo-optic dysplasia (SOD). The patient was a 9-year-old girl. She had a history of hypoglycemia attacks and growth-hormone deficiency. Endotropia and bilateral optic nerve atrophy had been diagnosed at the age of 2 years. She was referred to our hospital for further investigation. Visual acuity was limited to light perception in the right eye and 0.9 in the left eye with correction. Ophthalmoscopic examination revealed bilateral optic nerve hypoplasia and tortuous retinal vessels. Optical coherence tomography revealed foveal hypoplasia and retinal folds in the right eye. Magnetic resonance imaging of the brain indicated atrophy of the bilateral optic nerves with right dominance as well as atrophy of the optic chiasm and bilateral optic tracts. The pituitary gland also exhibited atrophy. We established a rare diagnosis of SOD with foveal hypoplasia and retinal folds of the fovea and surrounding areas. On the basis of genetic and environmental evidence, we hypothesize that a common factor causes both foveal hypoplasia and SOD. However, we have been unable to identify this factor in the present case. It is necessary to study similar cases in order to identify the common factor.

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We report a case of neurosyphilis that was found to be associated with optic atrophy without any other neurological signs. The patient was a 59-year-old man with a 3-year history of progressive bilateral visual loss with optic atrophy of unknown origin. His corrected visual acuity was hand movement in the right eye and 0.1 in the left eye. He had a limited residual visual field in inferotemporal region of the right eye, and central and inferior scotoma in the left eye. Optic nerve head atrophy was present in both eyes. Light-near dissociation was detected in both eyes, but there was no evidence of miosis. Neuroimaging revealed optic nerve atrophy, but there were no abnormal findings suggestive of a compressive lesion. Tests for serum and cerebrospinal fluid anti-syphilitic antibodies were positive. The cerebrospinal fluid cell count was high. HIV antibody was negative. As a result of these findings, we diagnosed neurosyphilis with optic atrophy. The patient was treated with penicillin intravenously for 2 weeks. Visual acuity and visual field did not improve, but serum and cerebrospinal fluid anti-syphilitic antibodies and the cerebrospinal cell count decreased. Syphilitic optic atrophy is a rare condition with a poor visual prognosis. Clinicians should be aware that optic atrophy can be caused by syphilis.

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We report a case of suspected optic neuropathy caused by IgG4-related ophthalmic disease (IgG4-ROD). A 71-year-old man presented to our department for examination with primary complaints of diminished visual acuity in the right eye and bilateral exophthalmos. His corrected vision was "hand motion" in his right eye and 0.8 in his left eye. The direct-light reflex was sluggish and incomplete in the right eye, and a relative afferent pupillary defect was present. No abnormality of the fundus was evident. Critical flicker frequency was unmeasurable in the right eye and 30 Hz in the left eye. Lacrimal gland enlargement was apparent on magnetic resonance imaging, serum levels of IgG4 were elevated, and histopathological findings from lacrimal gland biopsy revealed 30 IgG4-positive plasma cells per high-power field. Based on the diagnostic criteria for IgG4-ROD, we considered this as a possible diagnosis. The optic neuropathy was caused by pressure exerted on the optic nerve by an enlarged lacrimal gland. His corrected vision improved rapidly after the administration of systemic steroids. One must pay attention to the possibility that IgG4-ROD may cause a concomitant optic neuropathy. As previously reported in other studies, this condition responds well to steroid treatment.

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Eye movements are considered to be shifts of the visual axis. They are essentially two-dimensional, horizontal and vertical. In truth, however, eye movements must be considered rotations of the eyeball, since it is a rigid body. Therefore, eye movements are in fact three-dimensional: horizontal, vertical, and torsional around the visual axis. Since the rotation of a rigid body is non-commutative, the direction of the torsional component will be opposite when the orders of the horizontal and vertical rotations are reversed (Fick vs Helmholtz rotation). Voluntary eye movements, such as saccades, do not have torsional components and this phenomenon is known as Listing's law.We analyzed in detail the neural circuits involved in the execution of vertical saccades from the superior colliculus (SC) to the vertical ocular motoneurons in the cat, using intracellular recording and staining techniques. We found novel excitatory commissural connections between the symmetrical parts of the rostral SCs, where vertical saccades are represented. This finding strongly suggests that the excitatory commissural connections between the SCs are most likely involved in the regulation of pure vertical saccades by activating bilateral SCs simultaneously during vertical saccades and, for this reason, support Listing's law.

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Purpose: To describe the clinical characteristics and visual acuity outcome in methanol toxic optic neuropathy patients after treatment with high-dose intravenous methylprednisolone.
Method: This is a descriptive retrospective study. Data were gathered from the medical records of 244 patients (488 eyes) diagnosed with methanol toxic optic neuropathy over a 5 year period (January 2010 until December 2014). They were treated with high-dose intravenous methylprednisolone 1 g/day followed by oral methylprednisolone 1 mg/kg which was tapered off. The sex, age, onset of blurred vision, time interval between alcohol ingestion and the treatment, funduscopic examination and visual acuity during the initial assessment, on the third day and at the one week, two week and one month follow-up visits were obtained and analyzed.
Results: There were 244 patients included in our study. Two-hundred-twenty six (92.6%) were male. One-hundred-six (43.5%) were 26-35 years of age. One-hundred-sixty-nine (68.3%) had onset of visual loss 24 hours after alcohol exposure. One-hundred-eighty-seven (64.5%) had an interval that was 2 days – 1 week between alcohol ingestion and steroid treatment. One-hundred- sixty-five (67.6%) had optic disc swelling seen by funduscopy. Most patients had an initial visual acuity between light perception and counting fingers at 1 meter. On the third day of intravenous methylprednisolone treatment, 288 out of 488 eyes (59%) showed improvement of visual acuity, 175 eyes (35.8%) showed no improvement and 25 eyes (5.1%) had decreased visual acuity.
Conclusion: The majority of patients were male and most cases were between the ages of 26-35 years of age. Loss of visual acuity mostly occurred after 24 hours of alcohol ingestion and the majority of cases received treatment 2 days–1 week of alcohol ingestion. Fundusopic examination showed optic disc swelling in most cases. Treatment with high-dose intravenous methylprednisolone may improve visual acuity of patients with methanol toxic optic neuropathy.

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