Diagnostic Criteria For Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)

Warning:  This article, while intended to be read by ophthalmologists of all stages of training and practice, is extremely detailed.  It started out as a small literature review on a topic I see in clinic quite a bit, and devolved into a really long post.  While it may be less “review”-like than some of the other test-review articles I write, hopefully this clarifies a topic that was quite confusing to me when I was going through residency.

I have to be honest, I have been nervous venturing into the realm of the detailed literature review on this site.  As I’ve stated before, I am still pretty fresh out of training and while I aspire to grow this site as part of my own collection of thoughts and notes on learning the entirety of ophthalmology, I don’t always feel qualified to speak with authority on various topics.  Additionally, as a fellowship-trained neuro-ophthalmologist, I recognize that I will be more likely to find interest in writing more detailed articles about neuro-ophthalmology, sometimes at the expense of other topics.  Part of that is my own self-interest, but the other part is feeling qualified to know or develop sufficiently detailed literature review in other subjects.  For example, while I want to keep up my knowledge of corneal disease, I know that my depth of knowledge of corneal disease will likely never be as much as a fellowship-trained cornea surgeon.  Hopefully in the future, as I continue to build the site around the very basic topics, I will be able to recruit some contributors in different subspecialties to help provide the depth of understanding that I lack in those areas.  I’m also very open to input from you readers, since I want to make sure that while I am primarily building a website for my personal study, I can also provide useful material for you all as well.


Papilledema. No one wants to see this on a Friday afternoon.
Image from: Wikipedia

Pseudotumor cerebri syndrome (PTC, also referred to as idiopathic intracranial hypertension [IIH]) is classically taught as presenting in young, overweight women of childbearing age, with a history of headaches and findings of bilateral optic nerve swelling, associated with an elevated intracranial pressure.  However, as with every “textbook” definition of a disease, there are atypical cases (children, men, thin people, older people), and so I am often confronted with some interesting diagnostic challenges when I am referred a patient that does not fit the typical picture of PTC who has bilateral optic nerve swelling.

Of course, not every overweight young female with a headache has PTC.  And not all optic nerve swelling is papilledema.  And while I think that any patient with either should have a detailed funduscopic examination and at least have PTC in the differential diagnosis, some basic principles can be applied to help determine if those patients need further evaluation.  Also, for those of us who are either studying for ophthalmology exams or don’t have the luxury of having a neuro-ophthalmologist nearby to help, it’s useful to know what to do with these patients.

There are a lot of different aspects to cover with PTC, which I plan to eventually discuss (similar to my plans to cover the entire breadth of ophthalmology, even if it takes me the next 20 years).  So stay tuned for more articles covering PTC in the future!

Continue reading “Diagnostic Criteria For Pseudotumor Cerebri (Idiopathic Intracranial Hypertension)”

OKAP Review, Neuro-Ophthalmology: Optociliary Shunt Vessels

Optociliary (retinochoroidal) shunt vessels.
Image from: University of Iowa, EyeRounds.org.

Optociliary shunt vessels (retinochoroidal shunts), are normal congenital collaterals between the retinal and choroidal venous circulation.  In conditions that cause chronic central retinal vein obstruction, venous outflow becomes redirected to the choroidal venous circulation, resulting in dilation of these collateral vessels.  Because these are fully-formed vessels, they can be differentiated from disc neovascularization on fluorescein angiography by the lack of leakage.1

There are several pathologic conditions that result in the appearance of retinochoroidal shunt vessels: Continue reading “OKAP Review, Neuro-Ophthalmology: Optociliary Shunt Vessels”

OKAP Review, Neuro-Ophthalmology: Papilledema

Neuro-ophthalmology tends to have some of the more challenging questions, depending on your level of knowledge or comfort with these topics.  One of the important things to recognize and evaluate is the swollen optic nerve.


Image from: University of Iowa.

Papilledema, strictly defined, refers to optic nerve swelling (typically bilateral – for the test think of it this way) associated with increased intracranial pressure. Continue reading “OKAP Review, Neuro-Ophthalmology: Papilledema”