Block 5 Neuro Reglodi Case Reviews W Expl

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

Inferior colliculus

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

Craniopharyngioma

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.

Retinal detachment

Optic neuritis

Cataract

Glaucoma

Retinal hemorrhage

ROP

Retinitis pigmentosa

Macular degeneration

Oculocutaneous albinism

Papilla edema

Bitemporal hemianopia

Inferior quadrantanopia

Superior quadrantanopia

Homonymous hemianopia

Nasal hemianopia

Craniopharyngioma

Medulloblastoma

Meningioma

Retinoblastoma

ROP

Pituitary tumor

Temporal lobe epilepsy

Occipital lobe stroke

Acoustic neurinoma

Periventricular leukomalacia

Left Homonymous hemianopia

Bitemporal 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.

Nasal hemianopia

Bitemporal hemianopia

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

CN VI

CN III

CN V/1

CN VII

CN IV

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

Parinaud syndrome

Internuclear ophthalmoplegia

Horner syndrome

One-­‐and-­‐a-­‐half syndrome

Abducent nucleus

Trochlear nucleus

Pontine reticular formation

Oculomotor nucleus

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

CN VI

CN III

CN IV

MLF

PPRF

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