Elevated optic discs …Are they ever benign?

Dr Clare Fraser

Pathology

Swelling of the optic disc occurs when there is hold up of axonal transport at the level of the lamina cribrosa

= appearance is identical in apparently different pathological processes

Algorithm

True vs pseudo

Unilateral vs bilateral

Normal vs abnormal vision

True versus pseudo disc oedema

The first question to ask

Differences

True Blurred disc

margin Obscured vessels Hyperaemic Loss SVP (20%

normal patients)

Pseudo Vessels visible

crossing margin Anomalous

branching No micro-vascular

congestion

Pseudo-papilloedema

Drusen Hypermetropia Crowded discs Hyaloid remnants Myelinated nerve fiber layer

Optic disc drusen

Optic disc drusen

Drusen

OCT drusen

OCT drusen

Hyaloid remnant

Myelinated nerve fibres

Unilateral versus bilateralLess helpful but worth considering

Local or systemic

UNILATERAL

Local

Optic neuritis Vascular occlusion Infiltrative

BILATERAL

Systemic

Disc drusen Infectious optic

neuritis Papilledema Malignant

hypertension Toxicity

Normal versus abnormal vision

The final question to ask

Rule of thumb

Papilloedema preserved visual function

Papillitis secondary to local causes Poor visual function

Ischaemia visual loss is determined by the

occurrence of disc infarction

Disc swelling with vision loss Optic nerve

Optic neuritis Ischaemic ON▪ arteritic AION▪ NA-AION

Compressive orbital Infiltrative LHON

Vascular CRVO malignant

hypertension

Ocular Uveitis / posterior

scleritis Hypotony

Optic neuritis

Characteristic Patients

Female Caucasian Age Ocular pain Pain on eye m'ment

Optic disc Normal Swollen No retinal or disc Hb

Vision 6/6 or better 6/6 - 6/12 6/15 – 6/240CF or LP NPL

77%85%3292%87%

65%35%85%

11%25%49%13%3%

Optic neuritis - prognosis

90% will have 6/12 vision or better 75% will have 6/9 vision or better

40% develop Multiple Sclerosis in 10 years

30% have a relapse of optic neuritis in 5 years

Diabetic papillopathy

NAION

A-AION – giant cell arteritis

Compressive

LHON

Infiltrative optic neuritis

Leukaemia Lymphoma

CRVO

Malignant hypertension

Disc swelling without vision loss

Papilledema brain tumour thrombosis meningitis malignant

hypertension pseudo-tumor cerebri IIH

Optic nerve perineuritis diabetic papillopathy optic neuritis (early)*

Vascular CRVO

Early papilloedema

1 – C shaped halo with temporal gap

2 – circumferential halo

3 – loss major vessel leaving disc

4 – loss of vessels on the disc

5 – obscuration of all vessels

Chronic appearance

Disc swelling without vision loss

There are no clinically diagnosable causes of optic disc swelling with normal vision

All require some form of investigation

Urgency depends of speed of symptom onset

Simple things first Blood pressure Temperature (meningitis) Urine analysis (haematuria in vasculitis)

Increased intracranial pressure

Systemic hypertension

Space occupying lesion

Dural venous sinus thrombosis

Meningitis

Pseudotumour cerebri / IIH

Investigation

MRI and MRV with contrast

CT and CTV is sufficient

Referral for lumbar puncture

Idiopathic intracranial hypertension

Pseudotumour cerebri

Presentation of IIH

Headache

Pulsatile tinnitus

Transient visual obscurations

Double vision

Incidental finding at an optom visit

Headache

Daily diffuse non-pulsating Any location Worse lying flat or straining Wakes up with headache, clears after

30-60 minutes

Can sound migrainous – pulsating, unilateral

Increased ICP worsens all other types of headache tendencies

Diagnostic criteria of IIH

Signs and symptoms of increased ICP Headaches, nausea, vomiting, TVO,

papilledema No localising focal neurological signs

Except CN VI palsies CSF opening pressure >25cm H20

Normal constituents Normal neuroimaging

Exclude mass lesion, venous sinus thrombosisNo other underlying cause identifiable

Diagnostic criteria of IIH

“No other underlying cause identifiable”

So I prefer to use the term “pseudotumour cerebri”

Especially if the patient has BMI <25 Until I am happy there is no underlying

cause As a reminder to keep looking for one

Known causes PTC

Drugs Vit A, tetracyclines, steroids, some

NSAIDS, cyclosporin, OCP

Diseases COPD, sleep apnea, renal failure,

anaemia

IIH / PTC

Need urgent attention if rapid increase in symptoms acuity loss

Epidemiology of IIH

Obese women Dose relationship between BMI and risk Lower body (gynaecoid) adiposity

Childbearing age

Role of weight gain

Increased risk of IIH with 5-15% weight gain1

even if BMI remains <30 A return to a BMI similar to the time of first

presentation = risk for IIH recurrence2

even a 6% weight gain is a risk of recurrence BMI associated with more severe visual loss3

Even a 10% weight loss can be sufficient

1. Daniels et al. Profiles of obesity in IIH. AmJO 2007;143.2. Ko M et al. Weight gain in IIH. Neurology 2011;76.3. Szweka A et al. IIH obesity vs vision. JNO. July 2012

Dural venous sinus stenosis Seen in 80-100%

of adult IIH patients

There are no studies in children

Management Principles

Alleviate symptoms Headache

Preserve vision

While the patient loses weight

Immediate management

Based on Duration of symptoms Speed of symptom onset (?fulminant) Evaluation of visual function Patient characteristics

Male Black race Morbid obesity Anemia OSA

Acetazolamide (diamox)

1-2g daily in divided dose Decreases CSF production

Side effects Parasthesia, altered taste, lethargy Low K+

If not tolerated topiramate bendroflumethiazide

Visual loss

Optic nerve sheath fenestration Fulminant onset Other treatments failing to prevent

progressive vision loss Depends on local resources

ONSF

Produces a rapid reduction in pressure on the optic nerve head

Reduces papilledema Improves vision in operated eye +/- fellow eye Does not decrease ICP

? Causes local fistula formation

CSF diversion

Acute and rapidly progressive vision loss

Headache, no response to other therapy

Lumbar drain (transient) Ventriculo-peritoneal shunt Lumbar-peritoneal shunt

Dural venous sinus stenting

If increased pressure across stenosis

Reduces cerebral venous pressure Reduces ICP and improves

symptoms

Still not widely accepted in international community, frequently done in Sydney

Bariatric surgery

Conclusion about IIH

IIH is a diagnosis of exclusion

Pathophysiology is still not understood

There are no RCTs to guide management

Cases

Case 1

Seen by an optometrist, patchy HVF changes

Case 2

24 year old with reduced vision one eye

Case 3

34 yo presents with bilateral vision loss to 6/36 right and 6/12 left

Case 4

Referred ?disc swelling

Case 5

13 yo girl, 3 week history of severe headaches, nausea and vision loss to HMs in each eye

Case 5 (continued)

After lumbar puncture, optic nerve sheath fenestration and medical treatment, 6/36 OU

This is not a benign process