Does IIH increase the risk of cerebrovascular events?

Association between idiopathic intracranial hypertension and risk of cardiovascular diseases in women in the United Kingdom.

Adderley NJ, Subramanian A, Nirantharakumar K, et al.

JAMA Neurol 2019 (Epub ahead of print).



Cardiovascular disease (CVD) risk has not been previously evaluated in a large matched cohort study in idiopathic intracranial hypertension (IIH).


To estimate the risk of composite cardiovascular events, heart failure, ischemic heart disease, stroke/transient ischemic attack (TIA), type 2 diabetes, and hypertension in women with idiopathic intracranial hypertension and compare it with the risk in women, matched on body mass index (BMI) and age, without the condition; and to evaluate the prevalence and incidence of IIH.


This population-based matched controlled cohort study used 28 years of data, from January 1, 1990, to January 17, 2018, from The Health Improvement Network (THIN), an anonymized, nationally representative electronic medical records database in the United Kingdom. All female patients aged 16 years or older were eligible for inclusion. Female patients with IIH (n = 2760) were included and randomly matched with up to 10 control patients (n = 27 125) by BMI and age.


In total, 2760 women with IIH and 27 125 women without IIH were included. Age and BMI were similar between the 2 groups, with a median (interquartile range) age of 32.1 (25.6-42.0) years in the exposed group and 32.1 (25.7-42.1) years in the control group; in the exposed group 1728 women (62.6%) were obese, and in the control group 16514 women (60.9%) were obese. Higher absolute risks for all cardiovascular outcomes were observed in women with IIH compared with control patients. The aHRs were as follows: composite cardiovascular events, 2.10 (95% CI, 1.61-2.74; P < .001); heart failure, 1.97 (95% CI, 1.16-3.37; P = .01); ischemic heart disease, 1.94 (95% CI, 1.27-2.94; P = .002); stroke/TIA, 2.27 (95% CI, 1.61-3.21; P < .001); type 2 diabetes, 1.30 (95% CI, 1.07-1.57; P = .009); and hypertension, 1.55 (95% CI, 1.30-1.84; P < .001). The incidence of IIH in female patients more than tripled between 2005 and 2017, from 2.5 to 9.3 per 100 000 person-years. Similarly, IIH prevalence increased in the same period, from 26 to 79 per 100 000 women. Incidence increased markedly with BMI higher than 30.


Idiopathic intracranial hypertension in women appeared to be associated with a 2-fold increase in cerebrovascular disease risk; change in patient care to modify risk factors for CVD may reduce long-term morbidity for women with IIH and warrants further evaluation.

This paper is cited in the neurochecklist:

Idiopathic intracranial hypertension (IIH): typical clinical features 

Abstract link

Internet Archive Book Images on Flickr.
Neurochecklists updates

8 practical neurology numbers to welcome the new year!

As 2020 kicks in…

And you make your resolutions….

Here are some practical numbers

To kickstart the new year.

Numbers. Andy Maguire on Flickr.




The 16 MRI signs of IIH 


The 21 predictors of conversion from CIS to MS



The 25 unusual types of headaches



The 28 unusual presentations of myasthenia gravis



The 32 migraine co-morbidities



The 35 unusual presentations of MS



The 50 adverse effects of pembrolizumab



The 66 causes of trigeminal neuralgia

The Numbers. Annie Pilon on Flickr.


For more helpful neurology numbers in 2020

Keep up with

Numbers in a City. See-ming Lee on Flickr.
Neurochecklists updates

30 recently revised and updated practical neurology checklists

Neurochecklists is proud of being comprehensive and practical.

But more than that, we take pride in keeping each checklist updated.

To do this, we keep a keen eye on all relevant developments in the literature.

And below are just a few of the checklists that we have recently revised.

They all reflect findings from the latest neurology publications.


Anti Ma2 syndrome

Cerebral aneurysms rupture risk factors

Cerebral vein thrombosis

CGRP monoclonal antibodies


Dural AV fistula management

Giant cell arteritis treatment

Gluten sensitivity neurology

IIH clinical features

King-Denborough syndrome


Migraine acute treatment

MND c9orf72

Multiple sclerosis clinical features


Normal pressure hydrocephalus

Ocular myasthenia gravis

Oculopharyngeal muscular dystrophy


Parkinson’s disease risk factors

Post stroke recrudescence

PSP variants

Psychogenic seizures

Rapid onset dystonia-parkinsonism

Retinal migraine

Seizure manifestations

Stiff person syndrome

Subacute combined degeneration

Suprascapular neuropathy




What is the ideal CSF closing pressure at lumbar puncture for IIH?

Cerebrospinal fluid removal for idiopathic intracranial hypertension: less cerebrospinal fluid is best

Perloff MD, Parikh SK, Fiorito-Torres F, McAdams MT, Rayhill ML.

J Neuroophthalmol 2019; 39:330-332.



Although lumbar punctures (LPs) are used for diagnostic evaluation in idiopathic intracranial hypertension (IIH), they can also provide relief from IIH-associated headache. Conversely, low-pressure headache secondary to LP can be debilitating. Low-volume cerebrospinal fluid (CSF) removal to a “high-normal” closing pressure (CP), approximately 18-20 cm H2O, may result in relief of IIH-associated headache with a lowered frequency of post-LP headache.


We conducted a single-center retrospective analysis from 2011 to 2016 of patients who underwent fluoroscopic LPs aiming for high-normal CPs. Inclusion criteria were as follows: 1) pre-existing diagnosis of IIH, or opening pressure (OP) and clinical findings diagnostic for IIH; 2) height and weight recorded within 1 year; 3) documented LP data parameters; and 4) one week post-LP follow-up documenting whether headache was worse, unchanged, or better.


One hundred forty-six patients met the inclusion criteria. Mean age was 34.9 years ± 11.0, and mean body mass index was 39.2 kg/m ± 10.5. Mean volume removed was 9.7 mL ± 4.6. The mean CP was 17.9 cm H2O ±2.7. The mean pressure change (OP-CP) per volume removed was 1.50 cm H2O/mL ±0.6. Headache symptoms at follow-up were improved in 64% (80/125) of patients, worse in 26% (33/125), and unchanged in 10% (12/125). Eleven patients were headache-free, and 11 patients required hospital care for post-LP headache.


Low-volume CSF removal to approximately 18 cm H2O resulted in relief of IIH-associated headache in most patients and a low incidence of post-LP headache. Although clinically variable, these data suggest that for every 1 mL of CSF removed, the CP decreases approximately 1.5 cm H2O.

This paper is cited in the neurochecklist:

Idiopathic intracranial hypertension (IIH): other investigations

Abstract link

By unknown, maybe L.A. Marty, M.D, Kansas City (author of other photographies in this book) – Sophian, Abraham: Epidemic cerebrospinal meningitis (1913), St. Louis, C.V Mosby, p. 171 (Scan from, Public Domain, Link

What are the 10 most eminently curable neurological disorders?

Neurologists are often at the receiving end of the jokes of other medical specialists. They facetiously remark that neurologists know a lot, but do very little to cure their patients. Admittedly we do our fair share of dispensing weak platitudes, and we do break bad news with embarrassing regularity. There is no doubt that, for many diseases, all we have in stock are symptomatic or palliative. This is sadly the case with many familiar disorders such as Alzheimer’s disease (AD), Huntington’s disease, Charcot Marie Tooth disease (CMT), Freidreich’s ataxia (FA), essential tremor (ET), and myotonic dystrophy.

Three treatment capsules close-up. Marco Verch Professional Photographer and Speaker on Flickr.

It is even true that at the extreme end of neurological practice, there are conditions that literally turn a deaf ear to all our entreaties, brush off everything we hurl at them, taunt us with reckless abandon, and run relentlessly mortal courses. Such is the dismal state of affairs with diseases such as rabies encephalitis, Creutzfeldt Jakob disease (CJD), and motor neurone disease (MND).


Hypodermic needle-IMG7418. Steven Depolo on Flickr.

But neurologists don’t just tap their patients knees, and then raise their hands up in despair. We do more than just lend our patients a listening ear, or a leaning shoulder to cry on. We do have at our disposal a vast armamentarium that can control many neurological diseases, even if we need to use these chronically. Such is the state of play with diseases such as migraine, epilepsy, multiple sclerosis (MS), narcolepsy, myasthenia gravis (MG), restless legs syndrome (RLS)Wilson’s disease, and Parkinson’s disease (PD).

Mapping the brain. NIH History Office on Flickr.

But beyond just treatment, what patients really want is total cure. And neurologists can lay claim to this as well. Some diseases of the nervous system  can indeed be permanently remedied, their victims requiring no long-term medications to maintain the cure. To prove this, here are our 10 most eminently curable neurological disorders, linked to their treatment checklists.


Bacterial meningitis

Viral encephalitis

Autoimmune encephalitis

Wernicke’s encephalopathy

Ischaemic stroke

Idiopathic intracranial hypertension (IIH)

Cervical compressive myelopathy

Guillain Barre syndrome (GBS)


Normal pressure hydrocephalus (NPH)


It is important to note that curable neurological disorders are also potentially serious, and do carry the risk for serious complications, and even death, if not treated early and adequately. You may check out our previous blog posts to see the dark side of these disorders:

on ‘Have we missed anyone out? Please drop us a hint!

By JustfixingawrongnumberOwn work, CC0, Link

What are the microvascular abnormalities of idiopathic intracranial hypertension?

Cerebral microvascular abnormalities in patients with idiopathic intracranial hypertension.

Eidsvaag VA, Hansson HA, Heuser K, Nagelhus EA, Eide PK.

Brain Res 2018; 1686:72-82.



Idiopathic intracranial hypertension (IIH) is characterized by symptoms indicative of increased intracranial pressure (ICP), such as headache and visual impairment. We have previously reported that brain biopsies from IIH patients show patchy astrogliosis and increased expression of the water channel aquaporin-4 (AQP4) at perivascular astrocytic endfeet.


The present study was undertaken to investigate for ultrastructural changes of the cerebral capillaries in individuals with IIH. We examined by electron microscopy (EM) biopsies from the cortical parenchyma of 10 IIH patients and 8 reference subjects (patients, not healthy individuals), in whom tissue was retrieved from other elective and necessary brain surgeries (epilepsy, tumors or vascular diseases). IIH patients were diagnosed on the basis of typical clinical symptoms and abnormal intracranial pressure wave amplitudes during overnight ICP monitoring.


All 10 IIH patients underwent shunt surgery followed by favorable clinical outcome. Electron microscopy revealed abnormal pericyte processes in IIH. The basement membrane (BM) showed more frequently evidence of degeneration in IIH, but neither the BM dimensions nor the pericyte coverage differed between IIH and reference tissue. The BM thickness increased significantly with increasing age. Reference individuals were older than IIH cases; observations may to some extent be age-related.


The present study disclosed marked changes of the cerebral cortical capillaries in IIH patients, suggesting that microvascular alterations are involved in the evolvement of IIH.

This article is cited in the neurochecklist:

Idiopathic intracranial hypertension (IIH): investigations

Abstract link

By © Nevit Dilmen, CC BY-SA 3.0, Link

What is the benefit of dural venous sinus stenting for IIH?

Dural venous sinus stenting for medically and surgically refractory idiopathic intracranial hypertension

Satti SR, Leishangthem L, Spiotta A, Chaudry MI.

Interv Neuroradiol 2017; 23:186-193.



Idiopathic intracranial hypertension (IIH) is a syndrome defined by elevated intracranial hypertension without radiographic evidence of a mass lesion in the brain. Dural venous sinus stenosis has been increasingly recognized as a treatable cause, and dural venous sinus stenting (DVSS) is increasingly performed.


A 5 year single-center retrospective analysis of consecutive patients undergoing DVSS for medically refractory IIH.


There were 43 patients with a mean imaging follow-up of 6.5 months and a mean clinical follow-up period of 13.5 months. DVSS was performed as the first procedure for medically refractory IIH in 81.4% of patients, whereas 18.6% of patients included had previously had a surgical procedure (ventriculoperitoneal (VP) shunt or optic nerve sheath fenestration (ONSF)). Headache was present in all patients and after DVSS improved or remained stable in 69.2% and 30.8%, respectively. Visual acuity changes and visual field changes were present in 88.4% and 37.2% of patients, respectively. Visual field improved or remained unchanged in 92%, but worsened in 8% after stenting. There was a stent patency rate of 81.8%, with an 18.2% re-stenosis rate. Of the 43 procedures performed, there was a 100% technical success rate with zero major or minor complications.


Based on this single-center retrospective analysis, DVSS can be performed with high technical success and low complication rates. A majority of patients presented primarily with headache, and these patients had excellent symptom relief with DVSS alone. Patients presenting with visual symptoms had lower success rates, and this population, if stented, should be carefully followed for progression of symptoms.

Below is a related reference:

Liu KC, Starke RM, Durst CR, et al. Venous sinus stenting for reduction of intracranial pressure in IIH: a prospective pilot study. J Neurosurg 2017; 127:1126-1133.

Both references are cited in the neurochecklist:

Idiopathic intracranial hypertension (IIH): surgical treatment

Abstract 1

Abstract 2

By Henry Vandyke CarterHenry Gray (1918) Anatomy of the Human Body (See “Book” section below) Gray’s Anatomy, Plate 568, Public Domain, Link

The most unusual headache syndromes in neurology

Headaches constitute the bulk of what neurologists see in their general clinics. Most people with headaches fall neatly into one of two categories, migraine or tension type headache (TTH). The neurology clinic may have a sprinkling of people with cluster headache or paroxysmal hemicrania, two of the more common trigeminal autonomic cephalalgias (TACs). All these headaches are easy to recognise (most of the time), and easy to treat (until things get complicated).

By JD Fletcher –, CC BY-SA 3.0, Link

There are other common and readily recognisable headaches in the neurology clinic. Such headaches include idiopathic intracranial hypertension (IIH), medication overuse headache (MOH), chronic daily headache (CDH), post lumbar puncture headache (PLPH), and spontaneous intracranial hypotension (SIH).

Headache. Threephin on Flikr.

Several headaches are however rare and peculiar, many unheard of by many neurologists. These are the headaches which prompt the neurologist to delve into the textbooks, or phone an expert headache specialist. What are these distinctive and curious entities? Here are neurochecklists’ most unusual headaches.

Aeroplane headache

Bathing headache

Epicrania fugax

Exploding head syndrome

Glossopharyngeal neuralgia


(headache and neurological deficits with CSF lymphocytosis)

Hypnic headache

Ice cream headache

Idiopathic stabbing headaches


(long-lasting autonomic symptoms with associated hemicrania)

By Mike Faherty, CC BY-SA 2.0, Link

Nummular headache

Occipital condyle syndrome 

Raeder’s paratrigeminal syndrome

Sexual headache


(short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing)

Lego headache. Matt Brown on Flikr.

Space headache

Sphenopalatine neuralgia

Sunrise-related headache

TAC-TIC syndromes

Trochlear headaches 

Yawning headache

 Explore all of headaches on neurochecklists

Headache. Diego Fornero on Flikr.

Neurological infections

The 7 most devastating viral neurological infections

One may be forgiven for thinking that neurology is all about neuroinflammatory and neurodegenerative diseases. This is because these disorders seem to get a lot of attention. But nothing could be further from the truth-globally, infections impose a heavier burden on neurological practice than say Multiple Sclerosis (MS) or Parkinson’s disease (PD). And medical advances have done very little to deter all sorts of creatures from invading the nervous system.

Bacteria. Cesar Herada on Flikr.

The major types of organisms that infect the nervous system are viruses and bacteria, but fungi and parasites also take their toll. In this blog we will focus on the 7 most devastating viral neurological infections.

CC BY-SA 3.0, Link

1.  Viral encephalitis

Encephalitis is infection of the brain substance, as opposed to meningitis which is infection of the covering of the brain. Viral encephalitis, for some reason, tends to favour the temporal lobes of the brain causing seizures and memory problems, amongst other symptoms. The main villain responsible for viral encephalitis is herpes simplex type 1 (HSV1), but almost every other virus can carry out the job with deadly precision. The list is long and includes geographically specific viruses as West Nile and Japanese B. Check out the full list of causes of viral encephalitis and its management.

Herpes Simplex Virus Type 1: Procapsid and Mature Capsid. NIH Image gallery on Flikr.

2. HIV associated neurological infections

No part of the nervous system is immune to the ravages of the dreaded HIV. The list includes HIV  associated neurocognitive disorders (HAND)myelopathiesneuropathies, drug-induced syndromes, and tumours. The worst aspect of HIV, of course, is that it opens the flood gates for opportunistic infections to invade the nervous system.

By BruceBlausOwn work, CC BY-SA 4.0, Link

3. Hepatitis E virus (HEV)

Hepatitis E virus is just emerging as a scourge of neurology. It is particularly villainous because of its protean manifestations, from Guillain Barre syndrome (GBS) to neuralgic amyotrophy (brachial neuritis), from transverse myelitis to idiopathic intracranial hypertension (IIH). Check out the full neurological manifestations of HEV.

By Transferred from en.wikipedia to Commons.This media comes from the Centers for Disease Control and Prevention‘s Public Health Image Library (PHIL), with identification number #5605.Note: Not all PHIL images are public domain; be sure to check copyright status and credit authors and content providers.English | Slovenščina | +/−, Public Domain, Link

4. Influenza H1N1

Influenza is bad, and H1N1 is a particularly nasty variant. This subtype of Influenza A is epidemic in pigs and birds, and unleashes havoc when it crosses over to humans. Its nervous system manifestations include encephalopathyGuillain Barre syndrome (GBS), acute demyelinating encephalomyelopathy (ADEM), and stroke. Not one to be treated lightly at all. Check out everything about Influenza H1N1 and the different ways influenza affects the nervous system.

H1N1 influenza viral particles. NIAID on Flikr.

5. Zika virus infection (ZIKV)

This new kid on the infection block is fast establishing itself as a menace. Apart from causing myelitis, meningoencephalitis, encephalitis, encephalomyelitis, Guillain-Barre syndrome (GBS), and myasthenia gravis (MG), it is responsible for a variety of congenital defects, particularly microcephaly. Zika virus pathology and management are extensively covered in neurochecklists. Or check out 20 things we now know for certain about the Zika virus on our sister blog, The Neurology Lounge.

By Manuel Almagro RivasOwn work, CC BY-SA 4.0, Link

6. Ebola virus disease (EVD)

This ancient virus gained recent notoriety when it ravaged a large section of West Africa, sending chilling waves across the world. It is an RNA filovirus whose main reservoir is bats. It causes, among other things, an encephalitis and meningoencephalitis. It appears to be on vacation in the meantme, but it will surely rear its ugly head sometime soon. Check out the comprehensive clinical features and management of Ebola virus disease on neurochecklists.

By Scientific Animations –, CC BY-SA 4.0, Link

7. Varicella zoster virus (VZV)

The varicella virus must take the prize for the most diverse ways a virus affects the nervous system. Neurochecklists has listed >20 neurological manifestations of VZV, ranging from herpes zoster to post herpetic neuralgia (PHN), from meningitis to encephalitis. VZV also causes all forms of cranial and peripheral neropathy, and may result in stroke, aneurysms, and giant cell arteritis (GCA). Not to mention the curiously named progressive outer retinal necrosis (just don’t mention its acronym!). Check out the full VZV on neurochecklists.


Check out the other deadly viral neurological infections on neurochecklists:

Dengue virus infection (DENV)

West Nile virus (WNV) infection

Japanese encephalitis virus (JEV)

Rabies encephalitis