Midterm 4 Info (göz) Flashcards
What is glaucoma¿
Göz tansiyonu
What is optic neuritis¿
Inflammation of the optic nerve. Mostly viral
Usually young adults (5 females:1
male)
Visual acuity is usually affected with
central scotoma as the classic finding
Relative afferent pupillary defect may
persist even after the visual function
improves
Visual-evoked potential: prolonged
P100
What is papilledema¿
Papilödem, beyin içinde veya çevresinde artan basıncın göz içindeki optik sinirin bir kısmının şişmesine neden olan bir göz rahatsızlığıdır. Artan kafa içi basınç optik sinirin gözün arkasına girerken şişmesine neden olur.
Associated with bilateral optic disc edema due to elevated intracranial pressure
Compression of the venous structures within the nerve head that causes venous engorgement and tortuosity, capillary dilation, and splinter hemorrhage
Etiologies
i. Intracranial mass lesion
ii. Pseudotumor cerebri
iii. Hydrocephalus
iv. Intracranial hemorrhage
v. Venous thrombosis/obstruction
vi. Meningitis
What is Horner’s syndrome¿
Sempatik sinir sistem hasarının gözdeki hali.
Symptoms i. Miosis ii. Ptosis (denervation of Müller’s muscle) iii. Anhidrosis (ipsilateral facial)
May result from any one of a variety of factors:
• Carotid artery dissection
• The development of a tumor in neck or chest cavity, particularly a
neuroblastoma and a tumor of the upper part of the lung (Pancoast
tumor)
• The development of a lesion in midbrain, brain stem, upper spinal
cord, neck, or eye orbit
What are miosis midriasis and ptosis¿
Miosis—> Göz bebeğinin küçülmesi. Tersi midriasis.
Ptosis—> Göz kapağının düşmesi. Göz tembelliğine yol açar
AMAUROTIC LIGHT REFLEX nedir¿
Lesions of the optic nerve or retina on the affected side complete blindness
Absence of direct light reflex on the affected side AND absence of indirect light reflex on the normal side
relative afferent pupillary defect (RAPD) nedir
RÖLATİF AFERAN PUPİL DEFEKTİ (RAPD) (Marcus Gunn Pupil bir çeşididir): İnkomplet optik sinir lezyonu (glokom, optik nevrit, anterior iskemik optik nöropati vb.) veya şiddetli retinal hastalıklarda görülen bir durumdur. Fakat katarakt gibi durumlarda görülmez. Bu tablo en iyi “sallanan fener testi” ile tespit edilebilir
The swinging flashlight test is used to elicit a relative afferent pupillary defect (RAPD)
If you shine a light into one eye of a normal subject, both pupils constrict to the same degree. If you swing
the light over to the other eye, the pupil stays the same size or constricts minimally
In patients with RAPD the affected eye behaves as if it perceives a dimmer light than the normal eye;
therefore, both pupils constrict to a lesser degree when the light is shone in the affected eye
If you shine the light in the right eye of a patient with left RAPD, both pupils constrict. If you swing the light
to the left eye, it is perceived as dimmer and the pupils dilate
What is MARCUS GUNN PUPIL
It is a type of relative afferent pupil defect (RAPD)
Presence of a relative afferent pathway defect (RAPD) due to
incomplete optic nerve lesions or
severe retinal disease
Paradoxical response of a pupil to
light
Marcus Gunn pupil refers to the unequal pupillary response to light due to damage or disease in the retina or optic nerve.
ARGYLL ROBERTSON PUPIL what is it
Reaction to near reflex is present, but light reflex is absent
Lesions in the region of tectum
Both pupils are slightly small in size
ARGYLL ROBERTSON PUPIL (Light–Near Dissociation) reasons¿
Unilateral
• Afferent conduction defect
• Adie pupil
• Herpes zoster ophthalmicus
Aberrant regeneration of the third cranial nerve
Bilateral
• Neurosyphilis
• Type 1 diabetes mellitus
Myotonic dystrophy
Parinaud (dorsal midbrain) syndrome
Familial amyloidosis
Encephalitis
Chronic alcoholism
What is efferent pathway reflex
Absence of both direct & indirect light reflex and also near reflex on the affected side
Presence of all reflexes on normal side
Efferent pathway defect (sphincter paralysis)
Parasympatholytic drug (eg: atropine)
Internal opthalmoplegia
Third nerve paralysis
What is adie pupil¿
It typically affects young women and presents in one eye in
80%, though involvement of the second eye typically develops
within months or years. • Sites of dysfunction are presumed to be the ciliary ganglion • The affected pupil is larger (anisocoria). • Symptoms. Patients may notice anisocoria, or may have
blurring for near due to impaired accommodation.
• The direct light reflex is absent or sluggish • Constriction is also absent or sluggish in response to light
stimulation of the fellow eye (consensual light reflex • The pupil responds slowly to near, following which redilatation
is also slow. • Instillation of 0.1–0.125% pilocarpine into both eyes leads to
constriction of the abnormal pupil due to denervation
hypersensitivity, with the normal pupil unaffected.
ANISOCORIA nedir
Difference between the size of two pupils
The asymmetry persists to the same proportion under differing
levels of illumination
Physiological anisocoria: usually minimal, both pupils react well to light, no dilatation lag
Pathological anisocoria: Usually a difference of 2mm or more, may be either due to abnormal miosis or mydriasis of one pupil
Exceptionally, apraclonidine or cocaine testing may be needed to exclude Horner syndrome.
Info card
Acquired causes of pupil irregularity • Blunt trauma - focal tear in sphincter muscle • Iridodialysis - outer edge of iris is torn from ciliary attachment • Synechiae - inflammation can damage iris leading adherence to lens or cornea • Neovascularization- distort iris and impair reactivity • Surgical procedure in anterior segment, cataract
Optic nerve lesion results
Visual field deficits (anopsia)
Loss of light reflex with III
Only nerve to be affected by MS
Oculamotor nerve lesions
Diplopia, external strabismus • Loss of parallel gaze • Ptosis • Dilated pupil, loss of light reflex with II • Loss of near response
Function of oculamotor nerve
Innervates Superior rectus, medial rectus, inferior rectus, inferior oblique and
levator palpebra superioris • Raises eyelid (levator palpebrae superioris) • Constricts pupil (sphincter pupillae) • Accommodates (ciliary muscle)
