IDIOPATHIC INTRACRANIAL HYPERTENSION

IDIOPATHIC INTRACRANIAL HYPERTENSION

What is Idiopathic intracranial hypertension (IIH)?

IIH is a condition characterized by raised intracranial pressure (ICP) of unknown etiology. It is also known as benign intracranial hypertension or pseudotumor cerebri.

What are the common symptoms of IIH?

The commonest symptom of IIH is headache. In some cases, visual blurring or double vision may occur.

What is the dreaded complication in patients with IIH?

If IIH is left untreated, there is a threat to vision. Partial or complete loss of vision may occur. In many of these cases, vision may not revert to normal even after treatment.

How is the diagnosis of IIH confirmed?

The diagnostic criteria for IIH, including those of the Dandy criteria as described by Dandy in 1937 and later modified, are as follows (source: Medscape)

·       There are symptoms and signs of increased intracranial pressure

·       There are no localizing neurologic signs (with the exception of a unilateral or bilateral sixth nerve paresis)

·       Cerebrospinal fluid (CSF) may show increased pressure, but there are no cytologic or chemical abnormalities

·       Neuroimaging reveals no structural cause or hydrocephalus

·       No other causes of increased intracranial pressure found through workup

Subsequent additions to these criteria include the following

·       The diagnostic lumbar puncture should be performed with the patient in the lateral decubitus position

·       Magnetic resonance venography should be included to rule out intracranial venous sinus thromboses

What are the common abnormalities of IIH on MRI/MR Venogram brain?

Brain MRI with gadolinium contrast venogram is the imaging modality of choice, as it can effectively rule out meningitis/meningeal infiltrates, hydrocephalus, mass lesions, cerebral venous sinus thrombosis, etc. In addition, there are certain abnormalities, which are typically seen in patients with IIH:

·      Partial empty sella

·      Flattening of posterior globe

·      Distension of perioptic subarachnoid space

·      Vertical tortuosity of orbital optic nerve

What is the role of lumbar puncture in the diagnosis of IIH?

Lumbar puncture should be done in left lateral decubitus. It confirms the elevated ICP, opening pressure >200 mm water. Lumbar puncture also helps in excluding meningitis.

What is the mainstay of treatment?

Medical treatment with diamox (acetazolamide) is the primary treatment to be started in patients with IIH. Starting dose should be 500-1000 mg per day and a maximum dose of 4 grams per day can be used. Common side effects include paresthesia and tingling.

Diamox to lower intracranial pressure is indicated when there is 

1) visual field loss on automated perimetry, 

2) transient visual obscurations, 

3) binocular diplopia, or 

4) pulsatile tinnitus.

Does weight loss help in patients with IIH?

Yes, a weight loss of 5-10% can lead to substantial reduction in reducing symptoms of IIH and papilledema.

Do patients with IIH need surgery?

There are a group of patients that need surgery. Patients with severe papilledema with impending threat to visual loss or those presenting with loss of vision require an early surgery. Another group of patients who may need surgery are those that continue to worsen despite being on adequate doses of acetazolamide.

What are the surgical options in IIH?

1.     Optic nerve sheath fenestration

2.     CSF diversion procedures such as theco-peritoneal or ventriculo-peritoneal shunt surgery.

Dr Sudhir Kumar MD DM

Consultant Neurologist

Apollo Hospitals, Hyderabad

drsudhirkumar@yahoo.com

Headache After Ischemic Stroke

Headache after Ischemic Stroke

How common is headache after ischemic stroke?

Headache is common in people with ischemic strokes. It can occur at onset of stroke symptoms or following stroke. It affects 6-44% of people suffering from ischemic stroke.

What is the type of headache in this group of people?

Headache is similar to tension-type headache. It is located in back of head and neck regions. It is not very severe. There is no nausea or vomiting. There is no photophobia (increased sensitivity to lights) or phonophobia (increased sensitivity to sounds) either. 

Who have a higher risk of getting headaches after ischemic stroke?

1. Females have a higher risk than males.

2. Those suffering from posterior circulation stroke have a higher risk. 

3. Prevalence is higher in North America and Europe, as compared to Middle East and Asia. 

How can this be treated?

Medicines used for treating tension-type headache can be effective. These include amitriptyline or dothiepin (dosulepin) tablets. 

(Source: Neurology, Jan 7, 2020 issue)

Dr Sudhir Kumar MD DM
Consultant Neurologist
Apollo Hospitals, Hyderabad
drsudhirkumar@yahoo.com

MANAGING MULTIPLE SCLEROSIS IN PREGNANCY

Managing Multiple Sclerosis (MS) in Pregnancy

How common is this situation- pregnancy in women with MS?

MS is most often diagnosed between the ages of 20 to 40 years. This is the age when most women plan their pregnancies. Therefore, it is very common to find women with MS, who are pregnant or those who are planning pregnancy.

Which is a better option- starting MS treatment and then planning pregnancy or delaying MS treatments until after completing family?

MS is characterized by multiple relapses (when new symptoms occur). With each relapse, the disability increases. These relapses are often more frequent in the initial years after diagnosis of MS. Disease modifying drugs (DMD) can reduce relapses and disability. Therefore, it is always better to start DMD and then plan pregnancy. One should not postpone starting DMD after pregnancy/delivery.

How does pregnancy affect MS?

Pregnancy does not affect MS in the first trimester.

The MS relapses are lesser in 2^nd and 3^rd trimesters, which is good news.

However, the relapses become more frequent in the post partum period (after delivery) and this higher risk persists until 6 months after delivery.

How does MS affect pregnancy?

By and large, there are no adverse effects of MS on pregnancy. Women with MS have no extra risk of miscarriage or birth defects in their babies; as compared to women without MS. The mode of delivery too need not be altered just because the patient has MS.      

MS has no direct effect on fertility. Women with MS may have sexual dysfunction resulting in lesser libido. Male partners who have MS may suffer from erectile dysfunction.  

What MS medications are safe in pregnancy?

No DMD has yet been tested in pregnancy and hence none can be declared safe. However, recent evidence suggests that some DMDs are less risky than others. Less risky DMDs in pregnant women with MS include beta interferons (Avonex, Rebif, Betaseron) and Glatiramer acetate.

For prospective fathers, beta interferon and Glatiramer acetate as DMD showed no risk to baby’s health. Teriflunomide is detected in semen and it should be discontinued before trying to conceive.

Steroids can be safely used to treat MS relapses during pregnancy.

Will babies born to women with MS have a higher risk of getting MS themselves?

Most cases of MS are sporadic and most women with MS do not have a history of MS in their family members. However, having a relative with MS does slightly increase the risk of being diagnosed with MS.

In UK, the lifetime risk of being diagnosed with MS in general population in 1 in 330. The risk increases to 1 in 48, if one of the first degree relatives has MS. If one of the second-degree relatives has MS, the risk of being diagnosed with MS is 1 in 100.

an women with MS breastfeed?

Breastfeeding is safe and can be continued as usual.

What impact does pregnancy have on the course of MS?

There is limited data on this topic. However, in one study, pregnancy and childbirth were associated with lesser chances of developing severe disability. Women who gave birth at any time (either before or after the onset of MS) were 34% less likely to develop severe disability (as defined by need to use walking aid).

(For more reading, Multiple sclerosis Trust, UK)

Dr Sudhir Kumar MD DM
Consultant Neurologist
Apollo Hospitals, Hyderabad
04023607777
drsudhirkumar@yahoo.com