Approach to monocular vision

loss.Dr. Parag MoonSenior resident

Dept. of NeurologyGMC, Kota.

Transient visual loss (<24hr) Persistent visual loss(>24 hr)

◦ Sudden, painless◦ Gradual, painless◦ Painful

Monocular: anterior to chiasm Binocular: posterior to chiasm

Definition

1. Embolic cerebrovascular disease2. Ocular (intermittent angle closure

glaucoma, hyphema, impending central retinal vein occlusion, optic disc edema)

3. Vasculitis (GCA)4. Migraine/vasospasm5. Other (Uhthoff phenomenon, idiopathyic,

nonorganic)

Transient vision loss

Pathologically can be broadly divided into three major categories:

Media problems Retinal problems Neural visual pathway problems

Etiology

Keratitis• Infectious or non-infectious

Corneal edema• Acute glaucoma (primarily)

Hyphema• Spontaneous or traumatic

Alterations in crystalline lens• Thickening, clouding or dislocation

Vitreous hemorrhage• Spontaneous or traumatic Uveitis

Media problems

Inflammation of cornea due to trauma, abrasive exposure, allergy or infection.

Marked by cloudiness, irregularity or loss of epithelial or sub-epithelial corneal tissues.

Typically eye is tearing, red, painful or irritated. Loss of epithelial cells demonstrated by corneal

uptake of fluorescein dye, creating a focal or diffuse green glow under a cobalt blue light.

Deeper corneal disease may be visible as a focal or diffuse white opacity, or by dulling of usually distinct reflection of light off of cornea (corneal light reflex).

Keratitis 

Loss of corneal clarity. Dulling of corneal light reflex or frank grey or white color to

substance of cornea. Acute angle-closure glaucoma. Typically has nausea, vomiting, and may see coloured

halos around lights. Eye is tearing, red, and extremely painful, often with

ipsilateral brow ache. Pupil may be fixed in mid-dilated position Slit lamp examination- a shallow anterior chamber. IOP is often dangerously elevated (usually 40 to 80 mmHg). Suspected by noting hardness to palpation in comparison

to fellow eye. 

Corneal edema 

Blood in anterior chamber. May result from blunt trauma or may occur

spontaneously marked by abnormal growth or fragility of iris blood vessels (often in chronic poorly controlled diabetes).

Biomicroscopic examination reveals red blood cells circulating and/or layered in anterior chamber.

Intraocular pressure may become dangerously elevated.

Hyphema 

Changes in size, clarity, or positioning of the crystalline lens-alter focus of light onto retina.

Trauma or a variety of congenital conditions can lead to lens dislocation and resultant vision loss.

Lens clouding (cataract)-generally chronic. Elevated blood glucose can cause increased lens

tumescence, altering refractive error. If change is great enough, patients may perceive vision loss.

Vision impairment typically resolves within days to weeks of normalization of blood glucose

Lens changes

Can occur in setting of trauma, spontaneous retinal tear, spontaneous vitreous detachment or in any condition with retinal neovascularization (poorly controlled diabetes).

Reduction in vision directly proportional to amount of blood in vitreous.

Hemorrhage if dense enough, there may be a decreased red reflex (reddish orange reflection off subretinal layers when examining eye with an ophthalmoscope), or retina may not be visible with ophthalmoscopy.

Vitreous hemorrhage 

Inflammation of anterior structures of eye-red, painful light sensitivity

Isolated inflammation of intermediate and posterior structures-normal general appearance of eye with decrease in red reflex and/or complaint of new floaters.

Endophthalmitis- serious bacterial or fungal infection of all intraocular tissues, caused by surface pathogens (usually in recent ocular surgery) or blood-borne agents.

Eye is tearing, red, and painful. Biomicroscopic examination-white blood cells in

anterior chamber, vitreous space, or both. Hypopyon, corneal edema and decreased red reflex.

Uveitis

Retina problems Retinal vascular occlusion (CRAO, CRVO) Retinal detachment Acute maculopathy

Thrombosis, embolism, or arteritis of central retinal artery results in retinal ganglion cell damage, leading to severe, sudden, painless, central or paracentral visual loss.

Within minutes to hours-only abnormality noted on ophthalmoscopy may be vascular narrowing.

Embolus visible in 20 percent with CRAO. After several hours-inner layer of retina

becomes ischemic, turning milky white, except in fovea, which appears as a cherry-red spot.

Afferent papillary defect typically present.

Retinal artery occlusion 

Thrombosis of central retinal vein-venous stasis Disc swelling, diffuse nerve fiber layer and pre-

retinal hemorrhage, and cotton wool spots called "the blood and thunder" fundus.

While vision loss may be severe, the onset is typically subacute in contrast to sudden visual loss typical of CRAO.

When venous stasis is severe, infarction may occur due to slowed retinal blood flow on the arterial side. In this setting, a relative afferent papillary defect is often present.

Retinal vein occlusion

May occur spontaneously or trauma. Most common form-due to a tear or break in retina. Sudden onset of new floaters or black dots in their

vision, often accompanied by flashes of light (photopsias).

Not painful and does not cause a red eye. Dulling of red reflex and ophthalmoscopic

examination may reveal the retina to be elevated with folds.

If extensive, there may be a relative afferent pupillary defect.

Retinal detachment 

Associated with a central blind spot (scotoma), blurred vision, or visual distortion.

May be due to fluid leakage, bleeding, infection, or can occur de novo or as an acute worsening of a chronic disease (eg, new edema in previously dry diabetic retinopathy)

Diagnosis requires detailed ophthalmoscopy with a high magnification lens through pharmacologically dilated pupils.

Acute maculopathy

Optic nerve causes

Acute onset Central, cecocentral, arcuate pattern of

visual loss 75% normal disc Neurological signs of brain stem

(retrobulbar) (diplopia, ataxia, weakness) or spinal cord involvement (leg weakness, bladder symptoms, paresthesias, abnormal MRI)

90% recovery with steroids

Demyelinating optic neuritis

First described by Dutton and colleagues in 1982. Prone to recurrent optic neuritis events that respond

to corticosteroid therapy. Vision loss may manifest during a steroid taper More frequent in women. Optic nerve may appear mildly edematous during

acute events 79% have abnormal antinuclear antibody (ANA),82%

- elevated anticardiolipin antibody titers. Skin biopsy may show leukocytoclastic or

lymphohistiocytic vasculitis (or both) and immunereactant deposition

Autoimmune Optic Neuropathy

Nonspecific inflammation of optic nerve similar to typical optic neuritis

Infiltration of optic nerve or sheaths mimicking mass lesions, such as optic nerve glioma or meningioma

Mass effect due to direct compression of nerve

Parachiasmal involvement

Sarcoidosis

Typically affects young, healthy adults Two-thirds-antecedent viral prodrome. Cecocentral and central type visual field

defect. Present with stellate maculopathy and optic

disc edema, May be associated with exudative

detachment in peripapillary region.

Neuroretinitis

Multiple focal yellow-white retinal lesions may appear,

Optic disc edema associated with neuroretinitis typically begins to abate in 2 weeks, and resolve within 3 months.

Macular star may be present for up to a year.

Catscratch disease (Bartonella henselae), syphilis(treponema pallidum), Lymes disease(B. Burgdorfelia)

Neuroretinitis

Presence of severe disc edema with hemorrhages characteristic

Usually over 50 years old with Vascular risk factors such as diabetes, hypertension, and smoking.

in young patients (below 45 years) associated with hypercholesterolemia and hyperhomocysteinemia

Visual acuity can be normal or severely affected. Usually inferonasal arcuate or altitudinal. Optic nerve head in the other eye is often has small

cup-to-disc ratio (0.1 or less).

Non-arteritic ischemic optic neuropathy (NAION)

Visual acuity usually remains static or improves slightly in majority of patients

In a small subset of patients, visual acuity may actually worsen over the fi rst few weeks (progressive NAION).

Rarely lasts more than 3–4 weeks Bilateral simultaneous involvement can occur

during a hypotensive episode such as blood loss or over-dosing of anti-hypertensive medications.

Recurrence risk-5% in same eye, in follow eye within 5 years-15%

Non-arteritic ischemic optic neuropathy (NAION)

Over 60 year old with features of ischaemic neuropathy strongly consider possibility of giant cell arteritis (GCA).

Careful medical History inquiring about temporal pain, jaw claudications, transient visual or diplopia, fever, weight loss, myalgias and fatigue.

Cup-to-disk ratio of greater than 0.2 in other eye, Early massive or bilateral simultaneous visual loss Markedly pallid disk edema often described as

“chalky-white” swelling in 68.7% of cases

Arteritic ischemic optic neuropathy(AION)

Choroidal infarcts. End-stage optic disc appearance characterized

by marked cupping with pallor. Complete blood count, erythrocyte sedimentation

rate (ESR), and C-reactive protein (CRP). Steroid treatment either oral (80–120 mg

prednisone) or intravenous (1 gram methyleprdnisolone) for 3–5 days followed by oral steroids.

Defi nitive diagnosis by temporal artery biopsy and histopathological confirmation

Arteritic ischemic optic neuropathy(AION)

Optic nerve can be infiltrated in systemic malignancies such as lymphoma, leukemia, multiple myeloma, and carcinoma

Optic disc can be swollen or normal in appearance. MRI of brain and orbit may show meningeal and

optic nerve enhancement. Spinal tap recommended in suspected CNS

malignancy but more than one spinal tap may be needed to detect malignant cells

In case of localized optic nerve infiltration with no evidence of systemic disease, histopathological diagnosis by direct optic nerve sheath biopsy

Infiltrative optic neuropathies

Dominant optic neuropathy (Kjers’ type) Present in first decade of life Bilateral central or cecocentral scotomas. Color vision deficit along tritan (blue-yellow) axis. Optic disc-temporal pallor and in some cases

severe excavation and cupping. Recessive optic neuropathy rare First year of life Associated with diabetes mellitus, diabetes

inspidus, and deafness (Wolfram syndrome).

Hereditary optic neuropathy

Acute unilateral, painless, visual loss. Sequential bilateral involvement may occur

weeks or months later. Visual field defects-central or cecocentral as

papillo-macular bundle is first and most severely affected

Fundoscopy may show disk swelling, thickening of the peripapillary retinal nerve fiber layer and peripapillary retinal telangectatic vessels which do not leak on flourescin angiography.

Leber’s hereditary mitochondrial optic neuropathy

MRI-optic nerve enhancement and white matter lesions,

LHON has 4 primary mitochondrial genome mutations; G11778A, G3460A and T14484C and T10663C.

Male:female ratio-2.5:1 for G11778A and G3460A mutation

6:1 ratio for T14484C mutation.

Leber’s hereditary mitochondrial optic neuropathy

Present with vision loss, months or years following history of radiation exposure to brain or orbit.

Risk increased with concomitant chemotherapy .

Mechanism-ischemia caused by endothelial cell injury from radiation.

Optic disc is usually normal but can be swollen. MRI-optic nerve enhancement with gadolinium

Radiation optic neuropathy (RON)

May also have radiation retinopathy with retinal hemorrhages, cotton wool spots, exudates and macular edema.

Visual prognosis is poor with 45% ending with no light perception visual acuity.

Radiation optic neuropathy (RON)

Usually had suffered craniofacial trauma but occasionally mild orbital or eye injury.

RAPD-main clue to diagnosis. CT scan of orbit recommended detect any

bony fractures, fractures of optic canal, and acute orbital hemorrhages.

High-dose steroid therapy-within 8 hrs of injury

Traumatic optic neuropathy

Small cell and non-small cell lung carcinoma of lung

Often have bilateral disc swelling and progressive visual loss before diagnosis of systemic malignancy made.

Collapsing response-mediating protein (CRMP- 5) found to be useful marker with lung carcinoma.

Paraneoplastic optic neuropathy

Classically diagnosed by presence of progressive optic nerve cupping with concurrent progressive VF loss (arcuate nasal scotomas). 

Diagnosis aided by presence of risk factors such as elevated intraocular pressure (IOP), positive family history, predisposed race, advanced age and thin central corneal thickness

GLAUCOMATOUS OPTIC NEUROPATHY

Notching of the rim. Verticalization of the optic cup. Acquired optic pit. Baring of a circumlinear vessel. Vessel bayoneting at the optic rim (indicating bean-pot

cupping). Nasalization of vessels. Disc hemorrhage (Drance hemorrhage). Abnormally large or atypical pattern of peripapillary

atrophy (beta zone atrophy). Nerve not exhibiting rim pallor.

GLAUCOMATOUS OPTIC NEUROPATHY

History ◦ Timing — distinction between sudden onset of visual loss

and sudden discovery of preexisting visual loss. ◦ Laterality — Bilateral loss often suggests a retrochiasmal

visual pathway disorder.◦ Quality — Monocular or binocular◦ Pain — Keratitis -sharp superficial pain, acute glaucoma-

deep brow ache with nausea and vomiting, endophthalmitis- deep boring pain, optic neuritis-pain worse with eye movement.

◦ Redness — keratitis, acute glaucoma, and uveitis◦ Associated symptoms-diplopia, floaters, coloured halos,

neurological signs◦ Trauma

Approach to patient

Past medical history Vascular disease — diabetes, coronary artery disease,

hypertension, hypercoagulability, or vascular risk factors Refractive status Contact lens wear —microbial keratitis Eye surgery . Medications-

◦ Anticholinergics: loss of accommodation, angle closure glaucoma◦ Bisphosphonates: uveitis◦ Digoxin-yellow vision◦ Rifabutin: uveitis◦ Sildenafil- blue vision, ischemic optic neuropathy◦ Topiramate: angle closure glaucoma

Physical examination :◦ General inspection — noting erythema, tearing,

light sensitivity◦ Visual acuity — to be tested with glasses, one eye

at time◦ RAPD◦ Colour vision◦ Evaluation of extraocular movement◦ Confrontation visual fields

◦ Pupils — symmetry, reactivity to light, pupillary reflex◦ Fluorescein application◦ Intraocular pressure testing (by tonometry or

palpation)◦ Slit lamp exam◦ Ophthalmoscopic examination◦ Visual field testing (manual kinetic or automatic

static )◦ Visual evoked potentials◦ Pattern ERG◦ Fluroscein angiography◦ Optical coherence tomography (OCT)

Thank you

Diagnostic Approach to Vision Loss; Nancy Newman,Vale’rie Biousse; Continuum (Minneap Minn) 2014;20(4):785–815

Inflammatory Optic Neuropathies; Fiona Costello;Continuum Aug-2014

Approach to acute visual loss; Satish Khadilkar, Pramod Dhonde;Medicine Update 2012;Vol. 22

Clinical approach to optic neuropathies; Clinical Ophthalmology 2007:1(3) 233–246

www.update.com

References