TOG - Idiopathic Intracranial Hypertension Flashcards
What is the incidence of IIH?
1/100,000 women childbearing age
Increases to 19.3/100,000 in obese women
8:1 F:M
What are the common symptoms of IIH?
Headache
Transient visual obscuration
May aggravate pre-existing migraine
What are the common signs of IIH?
Papilloedema
Enlarged blind spot/field changes
Reduced visual acuity/colour vision
CNVI palsy - stretching of the nerve in 10%
What are the modified Dandy criteria to diagnose IIH?
- Signs and symptoms of increased intracranial pressure
- No localising neurologic signs otherwise, with the single exception being unilateral or bilateral sixth nerve paresis
- Cerebrospinal fluid can show increased pressure (>250mmH2O), but no cytologic or chemical abnormalities otherwise
- Normal to small symmetric ventricles must be demonstrated (originally required ventriculography, but now demonstrated by CT)
What is the recommended mode of delivery in IIH?
C/S only for obstetric reasons
>50% achieve VB
When in pregnancy does IIH tend to present?
Usually T1 but some cases in T3
What is the treatment of IIH in pregnancy?
- MDT
- Analgesics
- Diuretics to reduce CSF production
(acetazolamide - animal fetal effects; loop diuretics -
safe; avoid thiazides - FGR) - Dietary modification (weight loss)
- Steroids may be necessary acutely
Surgical options: - Repeat LPs - Optic nerve sheath fenestration - CSF diversion procedures necessary if vision being compromised
What are the anaesthetic considerations in women with IIH?
Spinal safe
Epidural may worsen if large vol of drugs in space
Lumboperitoneal shunt - may entangle
GA and RSI increases ICP
How often should visual fields be tested in IIH in pregnancy?
Depends on symptoms - if stable every 2-3/12
Is acetazolamide safe in breastfeeding?
Yes
What hormonal contraception is suitable in IIH?
Consult with neuro - case reports of association with progestorone-only
