Diagnosis: acute disseminating encephalomyelitis, resulting from the viral infection she had. This spread to orbital infection manifesting in blurry vision.
Diagnosis: Viral meningitis, leading to severe neck pain when looking downwards (nuchal rigidity), inhibiting her from seeing the play from the upper row. Later meningeal plaques led to the involvement of the optic nerve around the sellar region.
Multiple system degeneration, a neurodegenerative disease affecting long tracts along ventricles. The first attack was due to the optic radiation involvement along the border of the lateral ventricle. The viral infection she had before triggered the autoimmune disease. The second attack was due to the degenerating optic nerve on one side.
Diagnosis: carotid aneurism. The first attack was caused by the forced position of the head to see the play and so the aneurism was pushed against the optic chiasm from the side. The second attack was caused by slow further growth of the aneurism, compressing the optic nerve.
Diagnosis: multiple sclerosis. The first attack affected her optic radiation in the occipital lobe, resulting in inferior sectoranopia (not seeing well from the upper rows of the theater). Second attack affected her optic nerve, which is a very common symptom of this disease.
Inferior vestibular nucleus
Ventral cochlear nucleus
Superior olivary nucleus
Lateral geniculate nucleus
A sebum plug was swollen due to repeated water exposure, leading to a conductive hearing loss
Using Weber`s test, he could hear the sound better on his right side
Using Rinne`s test, he could hear the sound better when the fork was moved to his ear.
Middle ear infection is the most probable cause, resulting in sensorineural hearing loss
Applying the Epley`s maneuver, his condition got better
Rod bipolar cells transmit information when light is on
On bipolar cells are hyperpolarized when light is on in the center of the receptive field
Off ganglion cells are depolarized when on bipolar cells are depolarized
On ganglion cells increase their firing rate when their on bipolar cells are depolarized
Depolarization of a cone in the periphery of the receptive field leads to hyperpolarization of the on bipolar cell in the periphery
The chemotherapy damaged the vestibulocochlear nerve on both sides.
Cisplatin led to toxic damage of the outer hair cells.
Due to chemotherapy, one of the metastatic sites at the internal acoustic meatus got edemic, compressing the cochlear nerves.
Chemotherapy made the patient more susceptible to infections, and he had a severe middle ear infection, leading to hearing loss.
Metastatic spot in the rhomboid fossa in the vestibular area compressed one of the cochlear nuclei.
Retinal pigment is bleached and it needs time to recover
Sensitivity is very high and it will decrease only after a few minutes
Vision has to switch from scotopic to photopic vision
Rods are not active in sunlight and they need some time to be reactivated
11-‐cis retinal has to be reconverted into all trans retinal to be able to sense light in a dark room
Frontal lobe tumor involving the cortical eye field
Parietal lobe tumor leading to visual agnosia
Temporal lobe tumor with the involvement of the Meyer`s loop
Occipital lobe tumor around the calcarine sulcus
The most common form affects the rods
Blue color blindness is more common in men, because blue pigment gene is coded on the X chromosome
Red-‐green color blindness is more common in men, because these genes are coded on the X chromosome
Achromatopsia is the most common form of color blindness
Lack of red or green pigment alone leads only to mild color blindness
Occipital lobe tumor, with macular sparing. Because his high acuity vision was intact, he did not notice the visual problem.
Prostate cancer spreading in the brain and giving metastasis in different parts, explaining the variety of symptoms. The visual pathway was not affected.
Craniopharyngioma combined with ocular albinism. In ocular albinism, the nasal retinal fibers do not cross, that is why he did not have any visual deficits.
Pituitary tumor (causing acromegaly) growing downwards toward the sphenoid sinus instead of upwards, therefore not causing visual deficits.
Hypophyseal sclerosis due to the early head trauma. In this case, the hypophysis is shrinking instead of growing, so no visual deficit is caused.
Temporal lobe epilepsy
Occipital lobe stroke
Left Homonymous hemianopia
Left upper quadrantanopia
Lower right quadrantanopia
Right upper quadrantanopia
It is indeed unnecessary because temporal lobe surgery cannot cause visual problems, only occipital lobe surgery can.
Tractography would be indeed unnecessary because they have to remove the whole sclerotic lesion anyway, independent from the fibers of the optic tract passing through, leading to inferior quadrantanopia after surgery.
This examination is unnecessary because the optic tract runs at approximately the same position in everyone and conventional MRI can reveal subtle individual differences.
It is an additional technique to reveal the exact position of the optic tract fibers and combined with electrophysiological examination to determine the focus of epilepsy, they can indeed minimize the risk of visual deficit, which would be contralateral superior quadrantanopia
Tractography visualizes the long tracts and so the optic tract is visible. Thus, it is suitable for determining the extent of the surgical intervention to avoid lesion of the Meyer`s loop, which would result in contralateral inferior sectoranopia.
Contralateral homonymous quadrantanopia
Contralateral homonymous hemianopia
Ipsilateral nasal sectoranopia
Sodium channels are closed
CGMP levels are high
Phosphodiesterase is activated
Transducin is activated
Retinal detaches from opsin
Increased diplopia and asymmetry when looking to the right
Right eye does not adduct when looking to the left
Left eye does not abduct when looking to the left
Right eye abduction is impaired
Right eye is positioned down and out
Argyll Robertson syndrome
Pontine reticular formation
Medial longitudinal fascicle
Left trochlear nerve palsy with Marcus Gunn pupil
Left oculomotor nerve palsy with Horner syndrome
Left abducent nerve palsy with Argyll Robertson pupil
Left abducent nerve palsy with Marcus Gunn pupil
Left MLF lesion with midriasis
Increased intracranial pressure and vertical gaze palsy
Optic neuritis and CN VI lesion
Optic neuritis and CN IV lesion
Compression of the central retinal artery and Parinaud syndrome
Macular degeneration and horizontal gaze palsy
Here's an interesting quiz for you.